Genetic diversity, resistance profile of hiv and risk assessment of mother-to-child transmission in pregnant women on antiretroviral therapy in the Eastern Cape, South Africa
- Authors: Adeniyi, Oladele Vincent
- Date: 2019
- Subjects: Antiretroviral agents HIV infections -- Treatment -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15120 , vital:40183
- Description: Despite the initiation of life-long ART in HIV-infected pregnant women, the rate and determinants of infant HIV transmission are not known, especially in the poor resource settings of the Eastern Cape, South Africa. Maternal anti-retroviral therapy (ART) is crucial for elimination of mother-to-child transmission (MTCT) of HIV. However, the inevitable risks of emergence of HIV drug resistance poses significant threat to achieving this goal of HIV-free generation and keeping mothers alive. Also, it is unclear if women with high viral load at delivery have acquired clinically relevant mutations, which could confer resistance to the ART, thus, further increasing the risks of motherto-child transmission of HIV-drug resistance strains. In addition to the gaps identified in the prevention of mother-to-child transmission (PMTCT) context, the understanding of regional epidemics is crucial to the broader epidemiological profiling of HIV infections in the country. Despite the rapid influx of foreign nationals to South African and Eastern Cape Province, there has not been any molecular epidemiological studies profiling the HIV diversity in the Eastern Cape.
- Full Text:
- Date Issued: 2019
- Authors: Adeniyi, Oladele Vincent
- Date: 2019
- Subjects: Antiretroviral agents HIV infections -- Treatment -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15120 , vital:40183
- Description: Despite the initiation of life-long ART in HIV-infected pregnant women, the rate and determinants of infant HIV transmission are not known, especially in the poor resource settings of the Eastern Cape, South Africa. Maternal anti-retroviral therapy (ART) is crucial for elimination of mother-to-child transmission (MTCT) of HIV. However, the inevitable risks of emergence of HIV drug resistance poses significant threat to achieving this goal of HIV-free generation and keeping mothers alive. Also, it is unclear if women with high viral load at delivery have acquired clinically relevant mutations, which could confer resistance to the ART, thus, further increasing the risks of motherto-child transmission of HIV-drug resistance strains. In addition to the gaps identified in the prevention of mother-to-child transmission (PMTCT) context, the understanding of regional epidemics is crucial to the broader epidemiological profiling of HIV infections in the country. Despite the rapid influx of foreign nationals to South African and Eastern Cape Province, there has not been any molecular epidemiological studies profiling the HIV diversity in the Eastern Cape.
- Full Text:
- Date Issued: 2019
Genetic diversity, resistance profile of HIV and risk assessment of mother-to-child transmission in pregnant women on anti-retroviral therapy in the Eastern Cape, South Africa
- Authors: Adeniyi, Oladele Vincent
- Date: 2018-12
- Subjects: Antiretroviral agents http://id.loc.gov/authorities/subjects/sh2003006231 , AIDS (Disease) in infants http://id.loc.gov/authorities/subjects/sh90004332
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19817 , vital:43254
- Description: Despite the initiation of life-long ART in HIV-infected pregnant women, the rate and determinants of infant HIV transmission are not known, especially in the poor resource settings of the Eastern Cape, South Africa. Maternal anti-retroviral therapy (ART) is crucial for elimination of mother-to-child transmission (MTCT) of HIV. However, the inevitable risks of emergence of HIV drug resistance poses significant threat to achieving this goal of HIV-free generation and keeping mothers alive. Also, it is unclear if women with high viral load at delivery have acquired clinically relevant mutations, which could confer resistance to the ART, thus, further increasing the risks of motherto- child transmission of HIV-drug resistance strains. In addition to the gaps identified in the prevention of mother-to-child transmission (PMTCT) context, the understanding of regional epidemics is crucial to the broader epidemiological profiling of HIV infections in the country. Despite the rapid influx of foreign nationals to South African and Eastern Cape Province, there has not been any molecular epidemiological studies profiling the HIV diversity in the Eastern Cape. , Thesis (PhD) (Microbiology) -- University of Fort Hare, 2018
- Full Text:
- Date Issued: 2018-12
- Authors: Adeniyi, Oladele Vincent
- Date: 2018-12
- Subjects: Antiretroviral agents http://id.loc.gov/authorities/subjects/sh2003006231 , AIDS (Disease) in infants http://id.loc.gov/authorities/subjects/sh90004332
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/19817 , vital:43254
- Description: Despite the initiation of life-long ART in HIV-infected pregnant women, the rate and determinants of infant HIV transmission are not known, especially in the poor resource settings of the Eastern Cape, South Africa. Maternal anti-retroviral therapy (ART) is crucial for elimination of mother-to-child transmission (MTCT) of HIV. However, the inevitable risks of emergence of HIV drug resistance poses significant threat to achieving this goal of HIV-free generation and keeping mothers alive. Also, it is unclear if women with high viral load at delivery have acquired clinically relevant mutations, which could confer resistance to the ART, thus, further increasing the risks of motherto- child transmission of HIV-drug resistance strains. In addition to the gaps identified in the prevention of mother-to-child transmission (PMTCT) context, the understanding of regional epidemics is crucial to the broader epidemiological profiling of HIV infections in the country. Despite the rapid influx of foreign nationals to South African and Eastern Cape Province, there has not been any molecular epidemiological studies profiling the HIV diversity in the Eastern Cape. , Thesis (PhD) (Microbiology) -- University of Fort Hare, 2018
- Full Text:
- Date Issued: 2018-12
Skills for communicating severe acute respiratory syndrome-coronavirus-2 result to patients and/or relatives
- Adeniyi, Oladele Vincent, Kayembe, Dominique K
- Authors: Adeniyi, Oladele Vincent , Kayembe, Dominique K
- Date: 2021
- Subjects: COVID-19 Structured model Medical consultation Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7236 , vital:53095 , xlink:href="https://doi.org/10.4102/safp.v63i1.5221"
- Description: Clinicians notify positive results of the severe acute respiratory syndrome coronavirus-2 polymerase chain reaction to patients and/or relatives, whilst short message service (SMS) has been adopted as a means of disseminating negative results. Therefore, clinicians should be adequately equipped to provide telephonic consultation whilst delivering a positive test result to patients. The news of the coronavirus disease 2019 (COVID-19) test result often invokes fear of impending death in patients, especially the elderlies and those with comorbidities. In addition, several survivors have reported persistent symptoms and COVID-19-related stigma, which precludes them from immediate re-integration into their workplaces. Consequently, COVID-19 results are perceived as bad news by the members of the public. This article justifies why COVID-19 test results are bad news and also discusses the notification steps to follow when delivering COVID-19 results, whilst also addressing patients’ immediate concerns. The article concludes by highlighting an important safety net for COVID-19 patients and the attending clinician.
- Full Text:
- Date Issued: 2021
- Authors: Adeniyi, Oladele Vincent , Kayembe, Dominique K
- Date: 2021
- Subjects: COVID-19 Structured model Medical consultation Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7236 , vital:53095 , xlink:href="https://doi.org/10.4102/safp.v63i1.5221"
- Description: Clinicians notify positive results of the severe acute respiratory syndrome coronavirus-2 polymerase chain reaction to patients and/or relatives, whilst short message service (SMS) has been adopted as a means of disseminating negative results. Therefore, clinicians should be adequately equipped to provide telephonic consultation whilst delivering a positive test result to patients. The news of the coronavirus disease 2019 (COVID-19) test result often invokes fear of impending death in patients, especially the elderlies and those with comorbidities. In addition, several survivors have reported persistent symptoms and COVID-19-related stigma, which precludes them from immediate re-integration into their workplaces. Consequently, COVID-19 results are perceived as bad news by the members of the public. This article justifies why COVID-19 test results are bad news and also discusses the notification steps to follow when delivering COVID-19 results, whilst also addressing patients’ immediate concerns. The article concludes by highlighting an important safety net for COVID-19 patients and the attending clinician.
- Full Text:
- Date Issued: 2021
Management approach of patients with violent and aggressive behaviour in a district hospital setting in South Africa
- Adeniyi, Oladele Vincent, Puzi, Ntandazo
- Authors: Adeniyi, Oladele Vincent , Puzi, Ntandazo
- Date: 2021
- Subjects: mental health Emergency medical services violennce Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7284 , vital:53108 , xlink:href="https://doi.org/10.4102/safp.v63i1.5393"
- Description: Background: Given the physical and mental health consequences of tobacco use amongst individuals with mental illness, it was imperative to assess the burden of tobacco use in this population. Aim: This study examined the patterns and factors associated with tobacco use in individuals attending the outpatient unit. Setting: Cecilia Makiwane Hospital Mental Health Department in Eastern Cape province, South Africa. Methods: Lifetime (ever use) use and current use of any tobacco products were examined in a cross-sectional study of 390 individuals between March and June 2020. A logistic regression was fitted to determine the correlates of lifetime and current use of any tobacco products. Results: The rates of ever use and current use of tobacco products were 59.4% and 44.6%, respectively. Of the participants interviewed, lifetime tobacco use was more prevalent amongst individuals with schizophrenia (67.9%) and cannabis-induced disorders (97.3%) and lower in those with major depressive disorders (36.1%) and bipolar and related disorders (43.5%). Men were six times more likely to have ever used or currently use tobacco products in comparison to women. Also, those who had a salaried job or owned a business were over three times more likely to have ever used or currently use tobacco products compared with those receiving government social grants. Conclusions: The prevalence of tobacco use in this study was significantly higher than the general population in the Eastern Cape. Therefore, smoking prevention and cessation interventions targeted at the general population should target this often neglected sub-population in the region. Keywords: aggressive and violent behaviour; assisted user; emergency centres; involuntary user; Mental Health Care Act.
- Full Text:
- Date Issued: 2021
- Authors: Adeniyi, Oladele Vincent , Puzi, Ntandazo
- Date: 2021
- Subjects: mental health Emergency medical services violennce Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7284 , vital:53108 , xlink:href="https://doi.org/10.4102/safp.v63i1.5393"
- Description: Background: Given the physical and mental health consequences of tobacco use amongst individuals with mental illness, it was imperative to assess the burden of tobacco use in this population. Aim: This study examined the patterns and factors associated with tobacco use in individuals attending the outpatient unit. Setting: Cecilia Makiwane Hospital Mental Health Department in Eastern Cape province, South Africa. Methods: Lifetime (ever use) use and current use of any tobacco products were examined in a cross-sectional study of 390 individuals between March and June 2020. A logistic regression was fitted to determine the correlates of lifetime and current use of any tobacco products. Results: The rates of ever use and current use of tobacco products were 59.4% and 44.6%, respectively. Of the participants interviewed, lifetime tobacco use was more prevalent amongst individuals with schizophrenia (67.9%) and cannabis-induced disorders (97.3%) and lower in those with major depressive disorders (36.1%) and bipolar and related disorders (43.5%). Men were six times more likely to have ever used or currently use tobacco products in comparison to women. Also, those who had a salaried job or owned a business were over three times more likely to have ever used or currently use tobacco products compared with those receiving government social grants. Conclusions: The prevalence of tobacco use in this study was significantly higher than the general population in the Eastern Cape. Therefore, smoking prevention and cessation interventions targeted at the general population should target this often neglected sub-population in the region. Keywords: aggressive and violent behaviour; assisted user; emergency centres; involuntary user; Mental Health Care Act.
- Full Text:
- Date Issued: 2021
Beyond health care providers’recommendations: understandinginfluences on infant feeding choices ofwomen with HIV in the Eastern Cape,South Africa
- Adeniyi, Oladele Vincent, Ajayi, Anthony Idowu, Issah, Moshood, Owolabi, Eyitayo Omolara, Ter Goon, Daniel, Avramovic, Gordana, Lambert, John
- Authors: Adeniyi, Oladele Vincent , Ajayi, Anthony Idowu , Issah, Moshood , Owolabi, Eyitayo Omolara , Ter Goon, Daniel , Avramovic, Gordana , Lambert, John
- Date: 2017
- Subjects: Africa Infant Feeding Sub-sahara
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6063 , vital:45109 , https://doi.org/10.1186/s13006-019-0201-5
- Description: Background: Despite the array of studies on infant feeding practices of HIV-infected women, gaps still exist in the understanding of the underlying reasons for their infant feeding choices. Potential for behavioural change exists, especially in the light of the 2016 updated World Health Organization guideline on HIV and infant feeding. The aim of this paper is to determine the rate of adoption of exclusive breastfeeding in this cohort, examine the determinants of infant feeding choices of HIV-infected women and assess the underlying reasons for these choices. Methods: This was a mixed methods study conducted between September 2015 and May 2016. It analyses the quantitative and qualitative data of 1662 peripartum women enrolled in the East London Prospective Cohort Study across three large maternity services in the Eastern Cape. Women with HIV reported their preferred choices of infant feeding. In addition, participants explained the underlying reasons for their choices. Descriptive and inferential statistics summarised the quantitative data, while thematic content analysis was performed on qualitative data. Results: Of the 1662 women with complete responses, 80.3% opted to exclusively breastfeed their babies. In the adjusted model, up to grade 12 education level (AOR: 1.81; 95% CI: 1.14, 2.86), rural/peri-urban residence (AOR:1.44; 95% CI: 1.05, 1.96), alcohol use (AOR: 1.65; 95% CI: 1.25, 2.18), negative or unknown HIV status at booking (AOR:1.85; 95% CI:1.27, 2.70), currently married (AOR:1.43; 95% CI:1.01, 2.02) and WHO Clinical Stage 2–4 (AOR:1.77; 95% CI: 1.15, 2.72) were significantly associated with the decision to exclusively breastfeed. Health care providers’ recommendations, perceived benefits of breastfeeding, unaffordability of formula feeding, and coercion were the underlying reasons for wanting to breastfeed; while work/school-related demands, breast-related issues, and fear of infecting the baby influenced their decision to formula feed. Conclusion: The majority of HIV-infected women chose to breastfeed their babies in the Eastern Cape. Following up on these women to ensure they breastfeed exclusively, while also addressing their possible concerns, could be an important policy intervention. Future studies should focus on how early infant feeding decisions change over time, as well as the health outcomes for mother and child. Keywords: Exclusive breastfeeding, Infant feeding practice, infant formula feeding, HIV-infected peripartum women, South Africa, WHO guideline
- Full Text:
- Date Issued: 2017
- Authors: Adeniyi, Oladele Vincent , Ajayi, Anthony Idowu , Issah, Moshood , Owolabi, Eyitayo Omolara , Ter Goon, Daniel , Avramovic, Gordana , Lambert, John
- Date: 2017
- Subjects: Africa Infant Feeding Sub-sahara
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6063 , vital:45109 , https://doi.org/10.1186/s13006-019-0201-5
- Description: Background: Despite the array of studies on infant feeding practices of HIV-infected women, gaps still exist in the understanding of the underlying reasons for their infant feeding choices. Potential for behavioural change exists, especially in the light of the 2016 updated World Health Organization guideline on HIV and infant feeding. The aim of this paper is to determine the rate of adoption of exclusive breastfeeding in this cohort, examine the determinants of infant feeding choices of HIV-infected women and assess the underlying reasons for these choices. Methods: This was a mixed methods study conducted between September 2015 and May 2016. It analyses the quantitative and qualitative data of 1662 peripartum women enrolled in the East London Prospective Cohort Study across three large maternity services in the Eastern Cape. Women with HIV reported their preferred choices of infant feeding. In addition, participants explained the underlying reasons for their choices. Descriptive and inferential statistics summarised the quantitative data, while thematic content analysis was performed on qualitative data. Results: Of the 1662 women with complete responses, 80.3% opted to exclusively breastfeed their babies. In the adjusted model, up to grade 12 education level (AOR: 1.81; 95% CI: 1.14, 2.86), rural/peri-urban residence (AOR:1.44; 95% CI: 1.05, 1.96), alcohol use (AOR: 1.65; 95% CI: 1.25, 2.18), negative or unknown HIV status at booking (AOR:1.85; 95% CI:1.27, 2.70), currently married (AOR:1.43; 95% CI:1.01, 2.02) and WHO Clinical Stage 2–4 (AOR:1.77; 95% CI: 1.15, 2.72) were significantly associated with the decision to exclusively breastfeed. Health care providers’ recommendations, perceived benefits of breastfeeding, unaffordability of formula feeding, and coercion were the underlying reasons for wanting to breastfeed; while work/school-related demands, breast-related issues, and fear of infecting the baby influenced their decision to formula feed. Conclusion: The majority of HIV-infected women chose to breastfeed their babies in the Eastern Cape. Following up on these women to ensure they breastfeed exclusively, while also addressing their possible concerns, could be an important policy intervention. Future studies should focus on how early infant feeding decisions change over time, as well as the health outcomes for mother and child. Keywords: Exclusive breastfeeding, Infant feeding practice, infant formula feeding, HIV-infected peripartum women, South Africa, WHO guideline
- Full Text:
- Date Issued: 2017
Nanohybrid electrocatalyst based on cobalt phthalocyanine-carbon nanotube-reduced graphene oxide for ultrasensitive detection of glucose in human saliva
- Adeniyi, Omotayo, Nwahara, Nnamdi, Mwanza, Daniel, Nyokong, Tebello, Mashazi, Philani N
- Authors: Adeniyi, Omotayo , Nwahara, Nnamdi , Mwanza, Daniel , Nyokong, Tebello , Mashazi, Philani N
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231356 , vital:49880 , xlink:href="https://doi.org/10.1016/j.snb.2021.130723"
- Description: The current diabetes management systems require collecting blood samples via an invasive and painful finger pricking leading to the formation of callus, scarring and loss of sensibility to patients due to continuous monitoring. Therefore, a non-invasive and painless method of determining glucose levels would be desirable to diabetes patients who need constant monitoring. Saliva glucose measurement is a non-invasive alternative for diabetes management. A highly sensitive, stable, and selective non-enzymatic electrochemical sensor that can accurately quantify saliva glucose is required. A single-walled carbon nanotube/reduced graphene oxide/cobalt phthalocyanines nanohybrid modified glassy carbon electrode (GCE-SWCNT/rGO/CoPc) has been fabricated for the non-enzymatic determination of glucose in human saliva. The SWCNT/rGO/CoPc was characterized using various spectroscopic, microscopic, and electrochemical techniques. The synergistic effect between SWCNT, rGO, and CoPc facilitated excellent electron transfer process that improved the sensor sensitivity. The GCE-SWCNT/rGO/CoPc sensor exhibited two linear responses in the 0.30 μM to 0.50 mM and 0.50–5.0 mM glucose concentration ranges, and the detection limit was 0.12 μM. The sensor had an excellent saliva glucose detection sensitivity of 992.4 μA·mM−1·cm−2 and high specificity for glucose in the presence of other coexisting analytes. In addition, it showed good storage stability, reusability, and a fast response time of about 1.2 s. The GCE-SWCNT/rGO/CoPc nanohybrid electrode showed excellent potential for developing accurate, non-invasive, and painless glucose sensing.
- Full Text:
- Date Issued: 2021
- Authors: Adeniyi, Omotayo , Nwahara, Nnamdi , Mwanza, Daniel , Nyokong, Tebello , Mashazi, Philani N
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/231356 , vital:49880 , xlink:href="https://doi.org/10.1016/j.snb.2021.130723"
- Description: The current diabetes management systems require collecting blood samples via an invasive and painful finger pricking leading to the formation of callus, scarring and loss of sensibility to patients due to continuous monitoring. Therefore, a non-invasive and painless method of determining glucose levels would be desirable to diabetes patients who need constant monitoring. Saliva glucose measurement is a non-invasive alternative for diabetes management. A highly sensitive, stable, and selective non-enzymatic electrochemical sensor that can accurately quantify saliva glucose is required. A single-walled carbon nanotube/reduced graphene oxide/cobalt phthalocyanines nanohybrid modified glassy carbon electrode (GCE-SWCNT/rGO/CoPc) has been fabricated for the non-enzymatic determination of glucose in human saliva. The SWCNT/rGO/CoPc was characterized using various spectroscopic, microscopic, and electrochemical techniques. The synergistic effect between SWCNT, rGO, and CoPc facilitated excellent electron transfer process that improved the sensor sensitivity. The GCE-SWCNT/rGO/CoPc sensor exhibited two linear responses in the 0.30 μM to 0.50 mM and 0.50–5.0 mM glucose concentration ranges, and the detection limit was 0.12 μM. The sensor had an excellent saliva glucose detection sensitivity of 992.4 μA·mM−1·cm−2 and high specificity for glucose in the presence of other coexisting analytes. In addition, it showed good storage stability, reusability, and a fast response time of about 1.2 s. The GCE-SWCNT/rGO/CoPc nanohybrid electrode showed excellent potential for developing accurate, non-invasive, and painless glucose sensing.
- Full Text:
- Date Issued: 2021
Design of Immunobiosensors for Detection of Tumor-Associated Anti-P53 Autoantibodies: Method Development
- Authors: Adeniyi, Omotayo Kayode
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/162988 , vital:41002 , 10.21504/10962/162988
- Description: Introduction -- Experimental -- Label-Free Impedimetric Sensing of Anti-P53ab... -- Fluorescent detection of Anti-P53ab -- Peroxidase-like activity of Fe3O4@SiNP-APTES-Au@Pd... -- Colorimetric detection of Anti-P53ab , Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020. , Detection and profiling of circulating tumor-associated autoantibodies (TAAbs) are useful for screening and early-stage diagnosis of asymptomatic lung cancer. Immunobiosensor technologies aimed to accomplish the highly sensitive, rapid and low-cost detection of TAAbs can improve the early-stage detection of lung cancer. Immunobiosensors for the detection of anti-P53-tumour associated autoantibodies have been developed in this work. The design of sensing interfaces with immobilized P53 protein (P53ag) as a sensing element layer on a solid interface was investigated. Several methods of detecting anti-P53-antibodies (anti-P53ab) were investigated. These methods are label-free detection using electrochemical impedance spectroscopy (EIS) and two label techniques. The label-free electrochemical techniques utilize gold electrode pre-modified with a conducting layer of electrochemically grafted phenylethylamine for covalent immobilization of P53ag. The limit of anti-P53ab detection with the label-free EIS was 103.0 pg.ml-1. The labeled technique developed utilizes fluorescent, and peroxidase-like nanomaterial labeled antibody as a detection probe. For the fluorescence detection, fluorescent silica nanoparticles were synthesized by overloading FITC into the silica matrix and conjugated to detection antibody (anti-IgG). The detection of the anti-P53ab was based on the dissolution of the silica nanoparticles to release the loaded dye as a signal amplification strategy. The fluorescence detection was carried out on a microplate, and magnetic bead modified P53-antigen platforms and limit of detection (LoD) were 42.0 fg.ml-1 and 3.3 fg.ml-1 for anti-P53ab; respectively. Fe3O4@SiNP-APTES-Au@Pd hybrid nanoparticles were synthesized, and their peroxidase-like activity and colorimetric detection were evaluated. The Fe3O4@SiNP-APTES-Au@Pd exhibited comparable activity to HRP. The Fe3O4@SiNP-APTES-Au@Pd was conjugated to protein-G-anti-IgG for the detection of anti-P53ab on a microplate and cellulose paper platforms. The LoD was 20.0 fg.ml-1 and 63.0 fg.ml-1 for the microplate and cellulose paper platform; respectively. The potential application of the designed immunobiosensor was evaluated in simulated serum samples. The developed sensors showed higher detection sensitivity, stability and had a lower detection limit for anti-P53ab when compared with the ELISA based detection. The results have provided alternative and effective quantification approaches to ELISA and a promising future for multiplexed detection of tumor-associated autoantibodies. The developed methodologies in this thesis could be applied for the detection of other autoantibodies in other cancer types and auto-immune diseases.
- Full Text:
- Date Issued: 2020
- Authors: Adeniyi, Omotayo Kayode
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/162988 , vital:41002 , 10.21504/10962/162988
- Description: Introduction -- Experimental -- Label-Free Impedimetric Sensing of Anti-P53ab... -- Fluorescent detection of Anti-P53ab -- Peroxidase-like activity of Fe3O4@SiNP-APTES-Au@Pd... -- Colorimetric detection of Anti-P53ab , Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020. , Detection and profiling of circulating tumor-associated autoantibodies (TAAbs) are useful for screening and early-stage diagnosis of asymptomatic lung cancer. Immunobiosensor technologies aimed to accomplish the highly sensitive, rapid and low-cost detection of TAAbs can improve the early-stage detection of lung cancer. Immunobiosensors for the detection of anti-P53-tumour associated autoantibodies have been developed in this work. The design of sensing interfaces with immobilized P53 protein (P53ag) as a sensing element layer on a solid interface was investigated. Several methods of detecting anti-P53-antibodies (anti-P53ab) were investigated. These methods are label-free detection using electrochemical impedance spectroscopy (EIS) and two label techniques. The label-free electrochemical techniques utilize gold electrode pre-modified with a conducting layer of electrochemically grafted phenylethylamine for covalent immobilization of P53ag. The limit of anti-P53ab detection with the label-free EIS was 103.0 pg.ml-1. The labeled technique developed utilizes fluorescent, and peroxidase-like nanomaterial labeled antibody as a detection probe. For the fluorescence detection, fluorescent silica nanoparticles were synthesized by overloading FITC into the silica matrix and conjugated to detection antibody (anti-IgG). The detection of the anti-P53ab was based on the dissolution of the silica nanoparticles to release the loaded dye as a signal amplification strategy. The fluorescence detection was carried out on a microplate, and magnetic bead modified P53-antigen platforms and limit of detection (LoD) were 42.0 fg.ml-1 and 3.3 fg.ml-1 for anti-P53ab; respectively. Fe3O4@SiNP-APTES-Au@Pd hybrid nanoparticles were synthesized, and their peroxidase-like activity and colorimetric detection were evaluated. The Fe3O4@SiNP-APTES-Au@Pd exhibited comparable activity to HRP. The Fe3O4@SiNP-APTES-Au@Pd was conjugated to protein-G-anti-IgG for the detection of anti-P53ab on a microplate and cellulose paper platforms. The LoD was 20.0 fg.ml-1 and 63.0 fg.ml-1 for the microplate and cellulose paper platform; respectively. The potential application of the designed immunobiosensor was evaluated in simulated serum samples. The developed sensors showed higher detection sensitivity, stability and had a lower detection limit for anti-P53ab when compared with the ELISA based detection. The results have provided alternative and effective quantification approaches to ELISA and a promising future for multiplexed detection of tumor-associated autoantibodies. The developed methodologies in this thesis could be applied for the detection of other autoantibodies in other cancer types and auto-immune diseases.
- Full Text:
- Date Issued: 2020
Potential latitudinal variation in orodigestive tract cancers in Africa
- Adeola, H A, Adefuye, A O, Jimoh, S A
- Authors: Adeola, H A , Adefuye, A O , Jimoh, S A
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5280 , vital:44428 , http://www.samj.org.za/index.php/samj/article/view/12259
- Description: Background. Previous studies have alluded to a causal relationship between pathological entities and geographical variations, but there is a paucity of studies from Africa discussing the effect of latitudinal variation on orodigestive cancers in this region. It seems plausible that the burden of orodigestive cancer would differ as a result of variations in diet, cultural habits, climate and environmental conditions down the length of Africa. Objectives. To analyse regional variations in prevalence, incidence and mortality data in the global cancer statistics database (GLOBOCAN 2012) curated by the World Health Organization and the International Agency for Research on Cancer. Basic descriptive statistical tools were used to depict regional variations in cancer morbidity and mortality. Methods. Data on 13 African countries between longitude 20⁰ and 30⁰ east and latitude 35⁰ north and 35⁰ south were examined for variation in age-standardised orodigestive cancer prevalence, incidence and mortality. Possible regional causes for orodigestive tract cancer development were investigated. Data on lip and oral cavity, oesophageal, gastric, colorectal, liver, gallbladder and pancreatic cancers in the 13 countries were compared. Results. Our empirical findings from this preliminary study support the notion that the incidence and prevalence of orodigestive cancers vary within Africa. This effect may be due to environmental, economic, political and possibly genetic factors. Conclusions. Considering the heterogeneity of the above factors across Africa, disbursement of funding for cancer research and therapy in Africa should be focused in terms of regional variations to make best use of the fiscal allocation by African governments, non-governmental organisations and international agencies.
- Full Text:
- Date Issued: 2018
- Authors: Adeola, H A , Adefuye, A O , Jimoh, S A
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5280 , vital:44428 , http://www.samj.org.za/index.php/samj/article/view/12259
- Description: Background. Previous studies have alluded to a causal relationship between pathological entities and geographical variations, but there is a paucity of studies from Africa discussing the effect of latitudinal variation on orodigestive cancers in this region. It seems plausible that the burden of orodigestive cancer would differ as a result of variations in diet, cultural habits, climate and environmental conditions down the length of Africa. Objectives. To analyse regional variations in prevalence, incidence and mortality data in the global cancer statistics database (GLOBOCAN 2012) curated by the World Health Organization and the International Agency for Research on Cancer. Basic descriptive statistical tools were used to depict regional variations in cancer morbidity and mortality. Methods. Data on 13 African countries between longitude 20⁰ and 30⁰ east and latitude 35⁰ north and 35⁰ south were examined for variation in age-standardised orodigestive cancer prevalence, incidence and mortality. Possible regional causes for orodigestive tract cancer development were investigated. Data on lip and oral cavity, oesophageal, gastric, colorectal, liver, gallbladder and pancreatic cancers in the 13 countries were compared. Results. Our empirical findings from this preliminary study support the notion that the incidence and prevalence of orodigestive cancers vary within Africa. This effect may be due to environmental, economic, political and possibly genetic factors. Conclusions. Considering the heterogeneity of the above factors across Africa, disbursement of funding for cancer research and therapy in Africa should be focused in terms of regional variations to make best use of the fiscal allocation by African governments, non-governmental organisations and international agencies.
- Full Text:
- Date Issued: 2018
Factors affecting adherence to antiretroviral therapy among pregnant women in theEastern Cape, South Africa
- Adeola, H A, Adeniyi, Oladele Vincent, Ajayi, Anthony Idowu, Goon, Daniel Ter, Owolabi, Eyitayo Omolara, Eboh, Alfred, Lambert, John
- Authors: Adeola, H A , Adeniyi, Oladele Vincent , Ajayi, Anthony Idowu , Goon, Daniel Ter , Owolabi, Eyitayo Omolara , Eboh, Alfred , Lambert, John
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5272 , vital:44427 , https://neuro.unboundmedicine.com/medline/citation/29653510/Factors_affecting_adherence_to_antiretroviral_therapy_among_pregnant_women_in_the_Eastern_Cape_South_Africa_
- Description: Background:Context-specific factors influence adherence to antiretroviral therapy (ART) among pregnant womenliving with HIV. Gaps exist in the understanding of the reasons for the variable outcomes of the prevention ofmother-to-child transmission (PMTCT) programme at the health facility level in South Africa. This study examinedadherence levels and reasons for non-adherence during pregnancy in a cohort of parturient women enrolled in thePMTCT programme in the Eastern Cape, South Africa.Methods:This was a mixed-methods study involving 1709 parturient women in the Eastern Cape, South Africa. Weconducted a multi-centre retrospective analysis of the mother-infant pair in the PMTCT electronic database in 2016.Semi-structured interviews of purposively selected parturient women with self-reported poor adherence (n= 177)were conducted to gain understanding of the main barriers to adherence. Binary logistic regression was used todetermine the independent predictors of ART non-adherence.Results:A high proportion (69.0%) of women reported perfect adherence. In the logistic regression analysis, afteradjusting for confounding factors, marital status, cigarette smoking, alcohol use and non-disclosure to a family memberwere the independent predictors of non-adherence. Analysis of the qualitative data revealed that drug-related side-effects, being away from home, forgetfulness, non-disclosure, stigma and work-related demand were among the mainreasons for non-adherence to ART.Conclusions:Non-adherence to the antiretroviral therapy among pregnant women in this setting is associated withlifestyle behaviours, HIV-related stigma and ART side-effects. In order to eliminate mother-to-child transmission of HIV,clinicians need to screen for these factors at every antenatal clinic visit.Keywords:Adherence, Non-adherence, HIV, Antiretroviral therapy, Elimination of mother-to-child transmission,Prevention of mother-to-child transmission, Stigma, South Africa
- Full Text:
- Date Issued: 2018
- Authors: Adeola, H A , Adeniyi, Oladele Vincent , Ajayi, Anthony Idowu , Goon, Daniel Ter , Owolabi, Eyitayo Omolara , Eboh, Alfred , Lambert, John
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5272 , vital:44427 , https://neuro.unboundmedicine.com/medline/citation/29653510/Factors_affecting_adherence_to_antiretroviral_therapy_among_pregnant_women_in_the_Eastern_Cape_South_Africa_
- Description: Background:Context-specific factors influence adherence to antiretroviral therapy (ART) among pregnant womenliving with HIV. Gaps exist in the understanding of the reasons for the variable outcomes of the prevention ofmother-to-child transmission (PMTCT) programme at the health facility level in South Africa. This study examinedadherence levels and reasons for non-adherence during pregnancy in a cohort of parturient women enrolled in thePMTCT programme in the Eastern Cape, South Africa.Methods:This was a mixed-methods study involving 1709 parturient women in the Eastern Cape, South Africa. Weconducted a multi-centre retrospective analysis of the mother-infant pair in the PMTCT electronic database in 2016.Semi-structured interviews of purposively selected parturient women with self-reported poor adherence (n= 177)were conducted to gain understanding of the main barriers to adherence. Binary logistic regression was used todetermine the independent predictors of ART non-adherence.Results:A high proportion (69.0%) of women reported perfect adherence. In the logistic regression analysis, afteradjusting for confounding factors, marital status, cigarette smoking, alcohol use and non-disclosure to a family memberwere the independent predictors of non-adherence. Analysis of the qualitative data revealed that drug-related side-effects, being away from home, forgetfulness, non-disclosure, stigma and work-related demand were among the mainreasons for non-adherence to ART.Conclusions:Non-adherence to the antiretroviral therapy among pregnant women in this setting is associated withlifestyle behaviours, HIV-related stigma and ART side-effects. In order to eliminate mother-to-child transmission of HIV,clinicians need to screen for these factors at every antenatal clinic visit.Keywords:Adherence, Non-adherence, HIV, Antiretroviral therapy, Elimination of mother-to-child transmission,Prevention of mother-to-child transmission, Stigma, South Africa
- Full Text:
- Date Issued: 2018
Omics-based molecular techniques in oral pathology centred cancer: prospect and challenges in Africa
- Adeola, Henry A., Soyele, Olujide.O., Adefuye, Anthonio O., Jimoh, Sikiru A., Butali, Azeez
- Authors: Adeola, Henry A. , Soyele, Olujide.O. , Adefuye, Anthonio O. , Jimoh, Sikiru A. , Butali, Azeez
- Date: 2017
- Subjects: Eastern Cape, South Africa Oral mucosa--Cancer Oral Pathology Cancer Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5857 , vital:44658 , https://DOI10.1186/s12935-017-0432-8
- Description: Background:The completion of the human genome project and the accomplished milestones in the human proteome project; as well as the progress made so far in computational bioinformatics and “big data” processing have contributed immensely to individualized/personalized medicine in the developed world.Main body:At the dawn of precision medicine, various omics-based therapies and bioengineering can now be applied accurately for the diagnosis, prognosis, treatment, and risk stratification of cancer in a manner that was hitherto not thought possible. The widespread introduction of genomics and other omics-based approaches into the postgraduate training curriculum of diverse medical and dental specialties, including pathology has improved the proficiency of practitioners in the use of novel molecular signatures in patient management. In addition, intricate details about disease disparity among different human populations are beginning to emerge. This would facilitate the use of tailor-made novel theranostic methods based on emerging molecular evidences.Conclusion:In this review, we examined the challenges and prospects of using currently available omics-based technologies vis-à-vis oral pathology as well as prompt cancer diagnosis and treatment in a resource limited setting.Keywords:Omics-based, Molecular, Developing world, Oral pathology, Challenges
- Full Text:
- Date Issued: 2017
Omics-based molecular techniques in oral pathology centred cancer: prospect and challenges in Africa
- Authors: Adeola, Henry A. , Soyele, Olujide.O. , Adefuye, Anthonio O. , Jimoh, Sikiru A. , Butali, Azeez
- Date: 2017
- Subjects: Eastern Cape, South Africa Oral mucosa--Cancer Oral Pathology Cancer Computer File
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/5857 , vital:44658 , https://DOI10.1186/s12935-017-0432-8
- Description: Background:The completion of the human genome project and the accomplished milestones in the human proteome project; as well as the progress made so far in computational bioinformatics and “big data” processing have contributed immensely to individualized/personalized medicine in the developed world.Main body:At the dawn of precision medicine, various omics-based therapies and bioengineering can now be applied accurately for the diagnosis, prognosis, treatment, and risk stratification of cancer in a manner that was hitherto not thought possible. The widespread introduction of genomics and other omics-based approaches into the postgraduate training curriculum of diverse medical and dental specialties, including pathology has improved the proficiency of practitioners in the use of novel molecular signatures in patient management. In addition, intricate details about disease disparity among different human populations are beginning to emerge. This would facilitate the use of tailor-made novel theranostic methods based on emerging molecular evidences.Conclusion:In this review, we examined the challenges and prospects of using currently available omics-based technologies vis-à-vis oral pathology as well as prompt cancer diagnosis and treatment in a resource limited setting.Keywords:Omics-based, Molecular, Developing world, Oral pathology, Challenges
- Full Text:
- Date Issued: 2017
Agro-morphological characterisation, nitrogen use efficiency and combining ability of quality protein maize (zea mays l.) genotypes for low nitrogen tolerance
- AdeOluwa, Olusola Oluyinka https://orcid.org/ 0000-0003-2145-7141
- Authors: AdeOluwa, Olusola Oluyinka https://orcid.org/ 0000-0003-2145-7141
- Date: 2021-08
- Subjects: Corn -- Quality
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/21501 , vital:48855 , http://id.loc.gov/authorities/subjects/sh85032715
- Description: Low nitrogen stress tolerant Quality Protein Maize (QPM) genotypes will be of great benefit to farmers for increasing productivity in nitrogen depleted soils in the Eastern Cape (EC) Province, South Africa (SA). The current study evaluated: (i) QPM inbred lines for tolerance to low soil nitrogen, (ii) the Nitrogen Use Efficiency (NUE) of different QPM inbred lines, (iii) the combining ability of QPM genotypes for tolerance to low nitrogen, grain yield, and other agro-morphological traits, and (iv) the agro-morphological characteristics and adaptation of QPM hybrids to environments of different production potential in the Eastern Cape, South Africa. Thirty-two white-seeded QPM inbred lines obtained from CIMMYT-Zimbabwe and Quality Seeds (PTY) LTD were evaluated for tolerance to low soil nitrogen stress using two nitrogen (N) treatment levels: 0 kg N ha-1 and 30 kg N ha-1 under both glasshouse and field conditions at the Crop Research farm, University of Fort Hare, in two planting seasons. The study aimed at assessing the response of QPM inbred lines to low N, with a view to identifying low N tolerant types under both glasshouse and field conditions. Shoot length stress tolerance index (SHL STI) indicated lines L23, L29, L27, L13, L16, L17, L31, L14, L18 and L22 to be low soil N tolerant from the glasshouse study. From the field study, low N Stress Tolerance Index (STI) identified inbred lines L23, L31, L26, L28, L25, L29, L32, L4, L6, L3 and L2 as low soil N tolerant. These inbred lines also had high grain yields (GY) in the field under 0 kg N ha-1 (all ranked within the top ten except L2). They also had the potential for stable yields across environments considering their high Yield Stability Index (YSI), Mean Productivity (MP), Geometric Mean Productivity (GMP) and Stress Susceptibility Index (SSI) values. Both the glasshouse and field studies revealed inbred lines L22, L23, L26, L28, L25, L29 and L31 were common to both the glasshouse and field studies as being low soil N tolerant. These thirty-two parental QPM inbred lines were evaluated in the field for their nitrogen use efficiency (NUE) under five different nitrogen levels: 0, 30, 60, 90 and 120 kg N ha-1. The inbred lines studied under 0 kg N ha-1 and 30 kg N ha-1 indicated that N level expressed highly significant differences (P ≤ 0.001) for total nitrogen in biomass (Bio Total N), total nitrogen in grain (G Total N), grain yield (GY), nitrogen use efficiency (NUE) and almost all the indices estimated. The top six nutrient use efficient genotypes were L9, L14, L23, L25, L29 and L32 across N levels. However, the best and highest NUE was obtained from the lowest fertilizer dose, 30 kg N ha-1. Highly significant and positive correlation coefficients were found between Nitrogen Use Efficiency (NUE) and yield (+0.9), NUE and NUtE (+0.9), NUE and HI (Harvest Index) (+0.5), NUtE and yield (+0.99), HI and yield (+0.5) and NUtE and HI (+0.5). Thus, NUE, HI and NUtE could be good predictors of yield potential under low N soil conditions. Sixty-four testcross hybrids were generated from crossing these 32 QPM inbred lines with two QPM open pollinated varieties (OPVs) as testers in a line x tester design and were evaluated under 0 kg N ha-1 and 30 kg N ha-1 in the field. The objectives of the experiment were to: (i) identify high yielding hybrids with tolerance to low soil N in the EC; (ii) determine the combining abilities and mode of gene action for various traits under low and high nitrogen conditions; and (iii) group the inbred lines into heterotic groups for future use in the breeding program. Results revealed that under 30 kg N ha-1 (30N) condition, both additive and non-additive gene effects were observed with less importance of non-additive gene action for grain yield. Based on specific combining ability (SCA) effects, hybrids LNC22, LNC31, LOB22, LNC30, LNC29, LOB11, LNC18, LOB30, LOB19 and LNC24 showed outstanding performance under 0 kg N ha-1 (0N) condition with relatively acceptable SCA under 30N for yield. Inbred lines L6 (1.63), L22 (1.74), L29 (1.83) and L30 (1.24) showed positive and significant GCAs for grain yield under 0N. They were identified as the best combiners for grain yield as they were among the top ten performers for GCA under 0N. They can be very useful sources of low N tolerance genes. Two heterotic groups were formed under 0 kg N ha-1 and 30 kg N ha-1 conditions, and they will be useful for future hybrid development in the breeding program. Furthermore, these thirty-two QPM inbred lines were utilised as parental lines to generate seventy-six single cross hybrids. These single cross hybrids were evaluated across three environments of varying production potential in the Eastern Cape (EC), during the 2016/17 and 2017/18 summer seasons. Non-QPM hybrids namely PAN5Q649R and Phb31MO7BR, as well as QPM OPVs OBATANPA and Nelson's Choice were included in these preliminary variety trials (PVTs) as checks. Twenty-five hybrids expressing high values for the Smith – Hazel selection index were identified across sites over years. Among those hybrids were two checks, namely Q16 (PAN5Q649R) and Q33 (Phb31MO7BR). The top five high – yielding hybrids selected based on the selection index were considered to be the most productive, stable and adaptable based on the GGE biplot and AMMI stability values. None of these single cross hybrids over yielded the best hybrid check (Q16) in the current study. A high potential environment, Centane, was the ideal environments for evaluating genotypes in the present study. The studies showed inbred lines L22, L23, L26, L28, L25, L29 and L31 to be low N stress tolerant at 0 kg N ha-1 based on the low N stress tolerance indices under glasshouse and the field conditions; they were also among the top ten grain-yielders under field conditions at 0 kg N ha-1. Also, in the NUE study, they were found to be among the top ten most N-efficient inbred lines under low N soils, under 30 kg N ha-1, and were among the top twenty-four inbred lines with high NUE values across the N levels in the study. Inbred lines L29 and L22 also produced testcross hybrids that were among the top twenty based on GY under 0 kg N ha-1. The testcross hybrids produced from these inbred lines were also among the top twenty-five with outstanding SCA effects for GY. These inbred lines were also parental lines of some of the top twenty- five best hybrids selected based on the Smith – Hazel selection index in the PVT study. Inbred lines L22, L23, L26, L28, L25, L29 and L31 can therefore further be evaluated and used as sources of N-tolerance genes in QPM breeding programs. , Thesis (PhD) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-08
- Authors: AdeOluwa, Olusola Oluyinka https://orcid.org/ 0000-0003-2145-7141
- Date: 2021-08
- Subjects: Corn -- Quality
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/21501 , vital:48855 , http://id.loc.gov/authorities/subjects/sh85032715
- Description: Low nitrogen stress tolerant Quality Protein Maize (QPM) genotypes will be of great benefit to farmers for increasing productivity in nitrogen depleted soils in the Eastern Cape (EC) Province, South Africa (SA). The current study evaluated: (i) QPM inbred lines for tolerance to low soil nitrogen, (ii) the Nitrogen Use Efficiency (NUE) of different QPM inbred lines, (iii) the combining ability of QPM genotypes for tolerance to low nitrogen, grain yield, and other agro-morphological traits, and (iv) the agro-morphological characteristics and adaptation of QPM hybrids to environments of different production potential in the Eastern Cape, South Africa. Thirty-two white-seeded QPM inbred lines obtained from CIMMYT-Zimbabwe and Quality Seeds (PTY) LTD were evaluated for tolerance to low soil nitrogen stress using two nitrogen (N) treatment levels: 0 kg N ha-1 and 30 kg N ha-1 under both glasshouse and field conditions at the Crop Research farm, University of Fort Hare, in two planting seasons. The study aimed at assessing the response of QPM inbred lines to low N, with a view to identifying low N tolerant types under both glasshouse and field conditions. Shoot length stress tolerance index (SHL STI) indicated lines L23, L29, L27, L13, L16, L17, L31, L14, L18 and L22 to be low soil N tolerant from the glasshouse study. From the field study, low N Stress Tolerance Index (STI) identified inbred lines L23, L31, L26, L28, L25, L29, L32, L4, L6, L3 and L2 as low soil N tolerant. These inbred lines also had high grain yields (GY) in the field under 0 kg N ha-1 (all ranked within the top ten except L2). They also had the potential for stable yields across environments considering their high Yield Stability Index (YSI), Mean Productivity (MP), Geometric Mean Productivity (GMP) and Stress Susceptibility Index (SSI) values. Both the glasshouse and field studies revealed inbred lines L22, L23, L26, L28, L25, L29 and L31 were common to both the glasshouse and field studies as being low soil N tolerant. These thirty-two parental QPM inbred lines were evaluated in the field for their nitrogen use efficiency (NUE) under five different nitrogen levels: 0, 30, 60, 90 and 120 kg N ha-1. The inbred lines studied under 0 kg N ha-1 and 30 kg N ha-1 indicated that N level expressed highly significant differences (P ≤ 0.001) for total nitrogen in biomass (Bio Total N), total nitrogen in grain (G Total N), grain yield (GY), nitrogen use efficiency (NUE) and almost all the indices estimated. The top six nutrient use efficient genotypes were L9, L14, L23, L25, L29 and L32 across N levels. However, the best and highest NUE was obtained from the lowest fertilizer dose, 30 kg N ha-1. Highly significant and positive correlation coefficients were found between Nitrogen Use Efficiency (NUE) and yield (+0.9), NUE and NUtE (+0.9), NUE and HI (Harvest Index) (+0.5), NUtE and yield (+0.99), HI and yield (+0.5) and NUtE and HI (+0.5). Thus, NUE, HI and NUtE could be good predictors of yield potential under low N soil conditions. Sixty-four testcross hybrids were generated from crossing these 32 QPM inbred lines with two QPM open pollinated varieties (OPVs) as testers in a line x tester design and were evaluated under 0 kg N ha-1 and 30 kg N ha-1 in the field. The objectives of the experiment were to: (i) identify high yielding hybrids with tolerance to low soil N in the EC; (ii) determine the combining abilities and mode of gene action for various traits under low and high nitrogen conditions; and (iii) group the inbred lines into heterotic groups for future use in the breeding program. Results revealed that under 30 kg N ha-1 (30N) condition, both additive and non-additive gene effects were observed with less importance of non-additive gene action for grain yield. Based on specific combining ability (SCA) effects, hybrids LNC22, LNC31, LOB22, LNC30, LNC29, LOB11, LNC18, LOB30, LOB19 and LNC24 showed outstanding performance under 0 kg N ha-1 (0N) condition with relatively acceptable SCA under 30N for yield. Inbred lines L6 (1.63), L22 (1.74), L29 (1.83) and L30 (1.24) showed positive and significant GCAs for grain yield under 0N. They were identified as the best combiners for grain yield as they were among the top ten performers for GCA under 0N. They can be very useful sources of low N tolerance genes. Two heterotic groups were formed under 0 kg N ha-1 and 30 kg N ha-1 conditions, and they will be useful for future hybrid development in the breeding program. Furthermore, these thirty-two QPM inbred lines were utilised as parental lines to generate seventy-six single cross hybrids. These single cross hybrids were evaluated across three environments of varying production potential in the Eastern Cape (EC), during the 2016/17 and 2017/18 summer seasons. Non-QPM hybrids namely PAN5Q649R and Phb31MO7BR, as well as QPM OPVs OBATANPA and Nelson's Choice were included in these preliminary variety trials (PVTs) as checks. Twenty-five hybrids expressing high values for the Smith – Hazel selection index were identified across sites over years. Among those hybrids were two checks, namely Q16 (PAN5Q649R) and Q33 (Phb31MO7BR). The top five high – yielding hybrids selected based on the selection index were considered to be the most productive, stable and adaptable based on the GGE biplot and AMMI stability values. None of these single cross hybrids over yielded the best hybrid check (Q16) in the current study. A high potential environment, Centane, was the ideal environments for evaluating genotypes in the present study. The studies showed inbred lines L22, L23, L26, L28, L25, L29 and L31 to be low N stress tolerant at 0 kg N ha-1 based on the low N stress tolerance indices under glasshouse and the field conditions; they were also among the top ten grain-yielders under field conditions at 0 kg N ha-1. Also, in the NUE study, they were found to be among the top ten most N-efficient inbred lines under low N soils, under 30 kg N ha-1, and were among the top twenty-four inbred lines with high NUE values across the N levels in the study. Inbred lines L29 and L22 also produced testcross hybrids that were among the top twenty based on GY under 0 kg N ha-1. The testcross hybrids produced from these inbred lines were also among the top twenty-five with outstanding SCA effects for GY. These inbred lines were also parental lines of some of the top twenty- five best hybrids selected based on the Smith – Hazel selection index in the PVT study. Inbred lines L22, L23, L26, L28, L25, L29 and L31 can therefore further be evaluated and used as sources of N-tolerance genes in QPM breeding programs. , Thesis (PhD) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-08
Improved endoglucanase production and mycelial biomass of some ericoid fungi
- Adeoyo, Olusegun Richard, Pletschke, Brett I, Dames, Joanna F
- Authors: Adeoyo, Olusegun Richard , Pletschke, Brett I , Dames, Joanna F
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61435 , vital:28026 , https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209310/
- Description: Fungal species associated with ericaceous plant roots produce a number of enzymes and other bio-active metabolites in order to enhance survival of their host plants in natural environments. This study focussed on endoglucanase production from root associated ericoid mycorrhizal and dark septate endophytic fungal isolates. Out of the five fungal isolates screened, Leohumicola sp. (ChemRU330/PPRI 13195) had the highest relative enzyme activity and was tested along with isolates belonging to Hyloscyphaceae (EdRU083/PPRI 17284) and Leotiomycetes (EdRU002/PPRI 17261) for endoglucanase production under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28 °C. An optimal of pH 5.0 produced enzyme activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and Leohumicola sp. respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone. While NaFe-EDTA and Co2+ inhibited enzyme activity. The potential role of these fungi as a source of novel enzymes is an ongoing objective of this study.
- Full Text:
- Date Issued: 2017
- Authors: Adeoyo, Olusegun Richard , Pletschke, Brett I , Dames, Joanna F
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61435 , vital:28026 , https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5209310/
- Description: Fungal species associated with ericaceous plant roots produce a number of enzymes and other bio-active metabolites in order to enhance survival of their host plants in natural environments. This study focussed on endoglucanase production from root associated ericoid mycorrhizal and dark septate endophytic fungal isolates. Out of the five fungal isolates screened, Leohumicola sp. (ChemRU330/PPRI 13195) had the highest relative enzyme activity and was tested along with isolates belonging to Hyloscyphaceae (EdRU083/PPRI 17284) and Leotiomycetes (EdRU002/PPRI 17261) for endoglucanase production under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28 °C. An optimal of pH 5.0 produced enzyme activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and Leohumicola sp. respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone. While NaFe-EDTA and Co2+ inhibited enzyme activity. The potential role of these fungi as a source of novel enzymes is an ongoing objective of this study.
- Full Text:
- Date Issued: 2017
Bioprospecting for amylases, cellulases and xylanases from ericoid associated fungi, their production and characterisation for the bio-economy
- Authors: Adeoyo, Olusegun Richard
- Date: 2018
- Subjects: Mycorrhizal fungi , Hydrolases , Ericaceae South Africa , Ericaceae Molecular aspects
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/64327 , vital:28533
- Description: South Africa is one of the most productive areas for ericaceous plants with about 850 identified species in the Cape Floral Region. The Albany Centre of Endemism where all fungi used in this study were isolated from, falls within this region. Ericaceous plants interact with some fungi via an association called the ericoid mycorrhizal (ERM) association. All fungi used in this study were isolated from roots of six ericaceous plants; Erica cerinthoides, Erica demissa, Erica chamissonis, Erica glumiflora, Erica caffra and Erica nemorosa. Fungal enzymes are known to play a significant role in the food, brewing, detergent, pharmaceutical and biofuel industries. The enzyme industry is among the major sectors of the world, and additional novel sources are being explored from time to time. This study focussed on amylases (amyloglucosidase, AMG), cellulases (endoglucanase) and xylanases (endo-1,4-P-xylanase) production from ERM fungal isolates. Out of the fifty-one (51), fungal isolates screened, ChemRU330 (Leohumicola sp.), EdRU083 and EdRU002 were among the fungi that had the highest activities of all the enzymes. They were tested for the ability to produce amylases and cellulases under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28°C in a modified Melin-Norkrans (MMN) liquid medium. Cellulase specific activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and ChemRU330, respectively, was produced at an optimal pH of 5.0. For amylase, ChemRU330 had the highest specific activity of 1.11 U/mg protein while EdRU083 and EdRU02 had a specific activity of 0.80 and 0.92 U/mg protein, respectively, at the same pH with corresponding biomass yield of 113, 125 and 97 mg/50 ml, respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone, while NaFe-EDTA and cobalt inhibited enzyme activity. ChemRU330 was selected to determine the consistency and amount of amylase, cellulase and xylanase formed after several in vitro subculturing events. AMG and endo-1,4-P-xylanase were found to have the most consistent production throughout the study period. The AMG was stable at 45oC (pH 5.0), retaining approximately 65% activity over a period of 24 h. The molecular mass of AMG and endo-1,4-P-xylanase were estimated to be 101 kDa and 72 kDa, respectively. The Km and kcat were 0.38 mg/ml and 70 s-1, respectively, using soluble starch (AMG). For endo-1,4-P-xylanase, the Km and Vmax were 0.93 mg/ml and 8.54 U/ml, respectively, using beechwood xylan (endo-1,4-P-xylanase) as substrate. Additionally, crude extracts of five root endophytes with unique morphological characteristics were screened for antibacterial properties and was followed by determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). L. incrustata (ChemRU330) and Chaetomium sp. extracts exhibited varying degrees of inhibition against two Gram-positive and Gram-negative bacteria. The crude extract of L. incrustata was the most effective which was found to inhibit Staphylococcus aureus (MIC: 1 mg/ml), Bacillus subtilis (MIC: 2 mg/ml) and Proteus vulgaris (MIC: 16 mg/ml). The L. incrustata displayed potential for antibacterial production and could be considered as an additional source of new antimicrobial agents in drug and food preservation. Also, the three isolates used for enzyme production were identified to genus and species levels, i.e., Leohumicola incrustata (ChemRU330), Leohumicola sp. (EdRU083) and Oidiodendron sp. (EdRU002) using both ITS and Cox1 DNA regions. The molecular analysis results indicated that these ERM mycorrhizal fungi were similar to those successfully described by some researchers in South Africa and Australia. Therefore, this study opens new opportunities for exploring ERM fungal biomolecules for the bio-economy. The promising physicochemical properties, starch and xylan hydrolysis end- products, and being non-pathogenic make AMG and endo-1,4-P-xylanase potential candidates for future applications as additives in the food industry for the production of glucose, glucose syrups, high-fructose corn syrups, and as well as the production of bioethanol. Finally, the findings of this study revealed that it is possible to produce hydrolytic enzymes from ERM fungi in vitro using chemically defined media. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
- Date Issued: 2018
- Authors: Adeoyo, Olusegun Richard
- Date: 2018
- Subjects: Mycorrhizal fungi , Hydrolases , Ericaceae South Africa , Ericaceae Molecular aspects
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/64327 , vital:28533
- Description: South Africa is one of the most productive areas for ericaceous plants with about 850 identified species in the Cape Floral Region. The Albany Centre of Endemism where all fungi used in this study were isolated from, falls within this region. Ericaceous plants interact with some fungi via an association called the ericoid mycorrhizal (ERM) association. All fungi used in this study were isolated from roots of six ericaceous plants; Erica cerinthoides, Erica demissa, Erica chamissonis, Erica glumiflora, Erica caffra and Erica nemorosa. Fungal enzymes are known to play a significant role in the food, brewing, detergent, pharmaceutical and biofuel industries. The enzyme industry is among the major sectors of the world, and additional novel sources are being explored from time to time. This study focussed on amylases (amyloglucosidase, AMG), cellulases (endoglucanase) and xylanases (endo-1,4-P-xylanase) production from ERM fungal isolates. Out of the fifty-one (51), fungal isolates screened, ChemRU330 (Leohumicola sp.), EdRU083 and EdRU002 were among the fungi that had the highest activities of all the enzymes. They were tested for the ability to produce amylases and cellulases under different pH and nutritional conditions that included: carbon sources, nitrogen sources and metal ions, at an optimum temperature of 28°C in a modified Melin-Norkrans (MMN) liquid medium. Cellulase specific activity of 3.99, 2.18 and 4.31 (U/mg protein) for isolates EdRU083, EdRU002 and ChemRU330, respectively, was produced at an optimal pH of 5.0. For amylase, ChemRU330 had the highest specific activity of 1.11 U/mg protein while EdRU083 and EdRU02 had a specific activity of 0.80 and 0.92 U/mg protein, respectively, at the same pH with corresponding biomass yield of 113, 125 and 97 mg/50 ml, respectively. Increased enzyme activities and improved mycelial biomass production were obtained in the presence of supplements such as potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone, while NaFe-EDTA and cobalt inhibited enzyme activity. ChemRU330 was selected to determine the consistency and amount of amylase, cellulase and xylanase formed after several in vitro subculturing events. AMG and endo-1,4-P-xylanase were found to have the most consistent production throughout the study period. The AMG was stable at 45oC (pH 5.0), retaining approximately 65% activity over a period of 24 h. The molecular mass of AMG and endo-1,4-P-xylanase were estimated to be 101 kDa and 72 kDa, respectively. The Km and kcat were 0.38 mg/ml and 70 s-1, respectively, using soluble starch (AMG). For endo-1,4-P-xylanase, the Km and Vmax were 0.93 mg/ml and 8.54 U/ml, respectively, using beechwood xylan (endo-1,4-P-xylanase) as substrate. Additionally, crude extracts of five root endophytes with unique morphological characteristics were screened for antibacterial properties and was followed by determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). L. incrustata (ChemRU330) and Chaetomium sp. extracts exhibited varying degrees of inhibition against two Gram-positive and Gram-negative bacteria. The crude extract of L. incrustata was the most effective which was found to inhibit Staphylococcus aureus (MIC: 1 mg/ml), Bacillus subtilis (MIC: 2 mg/ml) and Proteus vulgaris (MIC: 16 mg/ml). The L. incrustata displayed potential for antibacterial production and could be considered as an additional source of new antimicrobial agents in drug and food preservation. Also, the three isolates used for enzyme production were identified to genus and species levels, i.e., Leohumicola incrustata (ChemRU330), Leohumicola sp. (EdRU083) and Oidiodendron sp. (EdRU002) using both ITS and Cox1 DNA regions. The molecular analysis results indicated that these ERM mycorrhizal fungi were similar to those successfully described by some researchers in South Africa and Australia. Therefore, this study opens new opportunities for exploring ERM fungal biomolecules for the bio-economy. The promising physicochemical properties, starch and xylan hydrolysis end- products, and being non-pathogenic make AMG and endo-1,4-P-xylanase potential candidates for future applications as additives in the food industry for the production of glucose, glucose syrups, high-fructose corn syrups, and as well as the production of bioethanol. Finally, the findings of this study revealed that it is possible to produce hydrolytic enzymes from ERM fungi in vitro using chemically defined media. , Thesis (PhD) -- Faculty of Science, Biochemistry and Microbiology, 2018
- Full Text:
- Date Issued: 2018
Active learning strategies used by teachers during English reading comprehension lessons in six selected primary schools in Nigeria
- Adepoju, Adetokunboh Abayomi
- Authors: Adepoju, Adetokunboh Abayomi
- Date: 2018
- Subjects: Education, Primary -- Nigeria Learning strategies -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8485 , vital:32838
- Description: Reading is an integral part of education from which one gets access to information. Unfortunately, reading ability among primary school pupils, the foundation level of education, is at its lowest ebb. These pupils when they get to secondary schools eventually fail external examinations-a situation which according to National Examination Council, is caused by inappropriate teaching methods. Consequent upon this, this study assessed active learning strategies used by teacher during English reading comprehension lessons in six selected primary schools in Nigeria. The main research question was: How do teachers employ active learning strategies in teaching English reading comprehension? The study adopted qualitative approach and case study design. With the use of purposive sampling technique to select six head teachers, six primary VI teachers, two members of the School Basic Committee, the Director Local Government Education Authority and six focus groups. The study used interviews, documents and focus group interview as research instruments to collect data. Data were analysed based on interpretivism paradigm which interpreted participants’ views according to the word view of the participants. The study found out that teachers have good knowledge of active learning strategies and use them in teaching English reading comprehension lessons but are faced with some daunting challenges such as non-availability of instructional materials, lack of library, lack of qualified teachers and lack of time. The study concluded that students fail woefully in English reading comprehension because teachers do not use appropriate teaching techniques. The study recommend that teachers must use active learning strategies effectively and more often during English reading comprehension, more time should be allocated for English reading comprehension, effective use of instructional materials should be considered and the government should employ specialist teachers to teach English reading comprehension.
- Full Text:
- Date Issued: 2018
- Authors: Adepoju, Adetokunboh Abayomi
- Date: 2018
- Subjects: Education, Primary -- Nigeria Learning strategies -- Nigeria
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8485 , vital:32838
- Description: Reading is an integral part of education from which one gets access to information. Unfortunately, reading ability among primary school pupils, the foundation level of education, is at its lowest ebb. These pupils when they get to secondary schools eventually fail external examinations-a situation which according to National Examination Council, is caused by inappropriate teaching methods. Consequent upon this, this study assessed active learning strategies used by teacher during English reading comprehension lessons in six selected primary schools in Nigeria. The main research question was: How do teachers employ active learning strategies in teaching English reading comprehension? The study adopted qualitative approach and case study design. With the use of purposive sampling technique to select six head teachers, six primary VI teachers, two members of the School Basic Committee, the Director Local Government Education Authority and six focus groups. The study used interviews, documents and focus group interview as research instruments to collect data. Data were analysed based on interpretivism paradigm which interpreted participants’ views according to the word view of the participants. The study found out that teachers have good knowledge of active learning strategies and use them in teaching English reading comprehension lessons but are faced with some daunting challenges such as non-availability of instructional materials, lack of library, lack of qualified teachers and lack of time. The study concluded that students fail woefully in English reading comprehension because teachers do not use appropriate teaching techniques. The study recommend that teachers must use active learning strategies effectively and more often during English reading comprehension, more time should be allocated for English reading comprehension, effective use of instructional materials should be considered and the government should employ specialist teachers to teach English reading comprehension.
- Full Text:
- Date Issued: 2018
Adoption and risk of mobile financial services: a case of some selected municipalities in Eastern Cape Province
- Authors: Aderibigbe, Ifeoluwa A.I
- Date: 2019
- Subjects: Mobile commerce Finance
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/13281 , vital:39630
- Description: The study investigated risk and adoption of mobile financial services among some users in selected municipalities within the Eastern Cape Province, using the theory of reason action, technology acceptance model and the theory of expected utility and risk aversion to explain the variables. Moreover, the explanatory research design and quantitative data collection approach formed the methodology adopted in the study. In addition, a validated semistructured interview questionnaire was used as a research instrument in the study. The multistage, stratify, purposive and convenience sampling techniques were applied to select 6 research sites and 386 research participants for the study. Three research objectives were stated and tested using descriptive, Principal Component Analysis (PCA) to profile the risk and logit regression statistics. The results of statistical analysis show different level of cross tabulation between MFS and education level, all the 6 different locations, individual age range, job type, and average income of individual. Analysis revealed that age and income level of individuals have the highest relationship with the use of MFS. The statistical analysis used was the logistic regression. Pool of effort of all the stake holders in financial services sector should focus on including the low income earners and the technology should be simple enough for the use of the older generation.
- Full Text:
- Date Issued: 2019
- Authors: Aderibigbe, Ifeoluwa A.I
- Date: 2019
- Subjects: Mobile commerce Finance
- Language: English
- Type: Thesis , Masters , MCom (Economics)
- Identifier: http://hdl.handle.net/10353/13281 , vital:39630
- Description: The study investigated risk and adoption of mobile financial services among some users in selected municipalities within the Eastern Cape Province, using the theory of reason action, technology acceptance model and the theory of expected utility and risk aversion to explain the variables. Moreover, the explanatory research design and quantitative data collection approach formed the methodology adopted in the study. In addition, a validated semistructured interview questionnaire was used as a research instrument in the study. The multistage, stratify, purposive and convenience sampling techniques were applied to select 6 research sites and 386 research participants for the study. Three research objectives were stated and tested using descriptive, Principal Component Analysis (PCA) to profile the risk and logit regression statistics. The results of statistical analysis show different level of cross tabulation between MFS and education level, all the 6 different locations, individual age range, job type, and average income of individual. Analysis revealed that age and income level of individuals have the highest relationship with the use of MFS. The statistical analysis used was the logistic regression. Pool of effort of all the stake holders in financial services sector should focus on including the low income earners and the technology should be simple enough for the use of the older generation.
- Full Text:
- Date Issued: 2019
Psychological capital and emotional intelligence as moderators of the relationship between occupational stress and organisational citizenship behaviour among graduate employees in Nigeria
- Authors: Aderibigbe, John Kolawole
- Date: 2017
- Subjects: Psychology, Industrial Emotional intelligence
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8642 , vital:33250
- Description: The study investigated psychological capital and emotional intelligence as moderators of the relationship between occupational stress and organisational citizenship behaviour among graduate employees in Nigeria, using the explanatory cross-sectional (survey) research design and three sampling techniques (The Two-stage Cluster Sampling Method, The Convenience Sampling Method and The Purposive Sampling Technique) to sample 1532 male and female graduate employees in Nigeria. A structured validated questionnaire was used to collect data from the respondents. Six hypotheses were stated and tested in the study towards propounding a model, using Pearson Correlation Analysis, Multiple Regression Analysis and Structural Equation Modelling. The results show that there is a weak positive relationship between occupational stress and organisational citizenship behaviour, r = 0.070, p<0.01; there is a significant positive relationship between psychological capital and organisational citizenship behaviour, r = 0.588, p<0.01; there is a significant positive relationship between emotional intelligence and organisational citizenship behaviour, r = 0.473, p<0.01; psychological capital is a significant moderator of the relationship between occupational stress and organisational citizenship behaviour, F (2,1529) = 8.514; R2= 0.011; p <.05; emotional intelligence is a significant moderator of the relationship between occupational stress and organisational citizenship behaviour, F (2,1529) = 5.945; R2= 0.008; p <.05; psychological capital and emotional intelligence are significant joint moderators of the relationship between occupational stress and organisational citizenship behaviour, F (1,1530) = 221.240; R2= 0.186; p <.05; psychological capital has a direct and significant positive effect on organisational citizenship behaviour, R= 0.657, p<.001; emotional intelligence has a direct and significant positive effect on organisational citizenship behaviour, R= 0.183, p<.001; psychological capital has a direct and significant positive effect on occupational stress, R= 0.100, p<.001; emotional intelligence has a direct and significant positive effect on psychological capital, R= 0.547, p<.001. Based on the results, the study concludes that psychological capital and emotional intelligence are significant joint moderators of the relationship between occupational stress and organisational citizenship behaviour. The proposed model was, therefore, empirically confirmed. The researcher recommends that the empirical model of effective management of occupational stress and organisational citizenship behaviour, which has been propounded in the study, should be adopted and applied by teachers, lecturers, seminar facilitators, workshop trainers, supervisors and managers during their coaching or training sessions.
- Full Text:
- Date Issued: 2017
- Authors: Aderibigbe, John Kolawole
- Date: 2017
- Subjects: Psychology, Industrial Emotional intelligence
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8642 , vital:33250
- Description: The study investigated psychological capital and emotional intelligence as moderators of the relationship between occupational stress and organisational citizenship behaviour among graduate employees in Nigeria, using the explanatory cross-sectional (survey) research design and three sampling techniques (The Two-stage Cluster Sampling Method, The Convenience Sampling Method and The Purposive Sampling Technique) to sample 1532 male and female graduate employees in Nigeria. A structured validated questionnaire was used to collect data from the respondents. Six hypotheses were stated and tested in the study towards propounding a model, using Pearson Correlation Analysis, Multiple Regression Analysis and Structural Equation Modelling. The results show that there is a weak positive relationship between occupational stress and organisational citizenship behaviour, r = 0.070, p<0.01; there is a significant positive relationship between psychological capital and organisational citizenship behaviour, r = 0.588, p<0.01; there is a significant positive relationship between emotional intelligence and organisational citizenship behaviour, r = 0.473, p<0.01; psychological capital is a significant moderator of the relationship between occupational stress and organisational citizenship behaviour, F (2,1529) = 8.514; R2= 0.011; p <.05; emotional intelligence is a significant moderator of the relationship between occupational stress and organisational citizenship behaviour, F (2,1529) = 5.945; R2= 0.008; p <.05; psychological capital and emotional intelligence are significant joint moderators of the relationship between occupational stress and organisational citizenship behaviour, F (1,1530) = 221.240; R2= 0.186; p <.05; psychological capital has a direct and significant positive effect on organisational citizenship behaviour, R= 0.657, p<.001; emotional intelligence has a direct and significant positive effect on organisational citizenship behaviour, R= 0.183, p<.001; psychological capital has a direct and significant positive effect on occupational stress, R= 0.100, p<.001; emotional intelligence has a direct and significant positive effect on psychological capital, R= 0.547, p<.001. Based on the results, the study concludes that psychological capital and emotional intelligence are significant joint moderators of the relationship between occupational stress and organisational citizenship behaviour. The proposed model was, therefore, empirically confirmed. The researcher recommends that the empirical model of effective management of occupational stress and organisational citizenship behaviour, which has been propounded in the study, should be adopted and applied by teachers, lecturers, seminar facilitators, workshop trainers, supervisors and managers during their coaching or training sessions.
- Full Text:
- Date Issued: 2017
Staff perceptions of workplace bullying in a South African higher education institution
- Authors: Adesemowo, Bosede Olaitan
- Date: 2018
- Subjects: Bullying in the workplace , Harassment Work environment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/23404 , vital:30539
- Description: During the past decade bullying has received growing attention in organizational research. Workplace bullying is a complex phenomenon with a variety of situational, dispositional and systemic influences and it has been defined as “status-blind interpersonal hostility that is deliberate, repeated and sufficiently severe as to harm the targeted person's health or economic status” (Namie, 2003:3). A literature overview revealed the destructive consequences of bullying, such as trauma, suicide, depression, anxiety, stress, lowered self-esteem, anger and a lessening of productivity for both the individuals and the organizations concerned. This study presents the perceptions of staff members, in the form of recognized trade union representatives, of workplace bullying at the Nelson Mandela Metropolitan University. The theoretical framework that informed the study comprised the dispositional and the ecological model that emphasised Ubuntu and the cultural values of the University. The research approach was carried out through qualitative and exploratory methods. Through primary and secondary data collection, a purposive sample of semi-structured interviews was collected in the context of the aim and the objectives of the study. It analysed the importance of an anti-bullying policy, management styles, power imbalances, the impact of bullying on staff and institution health and explored the existing supportive systems that deal with grievances procedures. This study concludes with concrete evidence that workplace bullying existed in Nelson Mandela University and there were no policies to effect control over perpetrators’ acts. Based on the findings of the study, recommendations are made regarding a strategy on how management can effectively address bullying complaints without prejudice and discrimination, such as an anti-bullying policy, and creating continuous awareness of the phenomenon.
- Full Text:
- Date Issued: 2018
- Authors: Adesemowo, Bosede Olaitan
- Date: 2018
- Subjects: Bullying in the workplace , Harassment Work environment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/23404 , vital:30539
- Description: During the past decade bullying has received growing attention in organizational research. Workplace bullying is a complex phenomenon with a variety of situational, dispositional and systemic influences and it has been defined as “status-blind interpersonal hostility that is deliberate, repeated and sufficiently severe as to harm the targeted person's health or economic status” (Namie, 2003:3). A literature overview revealed the destructive consequences of bullying, such as trauma, suicide, depression, anxiety, stress, lowered self-esteem, anger and a lessening of productivity for both the individuals and the organizations concerned. This study presents the perceptions of staff members, in the form of recognized trade union representatives, of workplace bullying at the Nelson Mandela Metropolitan University. The theoretical framework that informed the study comprised the dispositional and the ecological model that emphasised Ubuntu and the cultural values of the University. The research approach was carried out through qualitative and exploratory methods. Through primary and secondary data collection, a purposive sample of semi-structured interviews was collected in the context of the aim and the objectives of the study. It analysed the importance of an anti-bullying policy, management styles, power imbalances, the impact of bullying on staff and institution health and explored the existing supportive systems that deal with grievances procedures. This study concludes with concrete evidence that workplace bullying existed in Nelson Mandela University and there were no policies to effect control over perpetrators’ acts. Based on the findings of the study, recommendations are made regarding a strategy on how management can effectively address bullying complaints without prejudice and discrimination, such as an anti-bullying policy, and creating continuous awareness of the phenomenon.
- Full Text:
- Date Issued: 2018
Design of immunosensor for the detection of C-reactive protein using oriented antibody immobilization
- Authors: Adesina, Abiola Olanike
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163080 , vital:41010 , https://dx.doi.org/10.21504/10962/163080
- Description: Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020.
- Full Text:
- Date Issued: 2020
- Authors: Adesina, Abiola Olanike
- Date: 2020
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/163080 , vital:41010 , https://dx.doi.org/10.21504/10962/163080
- Description: Thesis (PhD)--Rhodes University, Science Faculty, Department of Chemistry, 2020.
- Full Text:
- Date Issued: 2020
Apparent digestibility coefficients of feed ingredients and essential amino acid requirements of dusky kob (Argyrosomus japonicus)
- Authors: Adesola, Abidemi Adejoke
- Date: 2017
- Subjects: Amino acids in animal nutrition , Fishes -- Feeding and feeds , Argyrosomus japonicus , Argyrosomus , Argyrosomus japonicus -- Nutrition , Argyrosomus -- Nutrition , Argyrosomus japonicus -- Feeding and feeds , Argyrosomus -- Feeding and feeds
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/32140 , vital:24014
- Description: Important to the evaluation of potential feed ingredients for inclusion in fish diets should be their digestibility and amino acid requirement so that feeds can be formulated on a digestible basis rather than a gross nutrient basis. This thesis established techniques for faecal collection, the validity of digestibility markers, it determined apparent digestibility coefficients for various novel feed ingredients, and it established the optimal lysine requirement for Argyrosomus japonicus, which was used to estimate each of the essential amino acid requirements by using the ideal protein concept. There were no significant differences in dry matter apparent digestibility coefficients when faeces were collected by stripping (77.0 %), dissection (80.1 %) or settlement (83.5 %). Faecal collection by the settlement method produced the most reliable digestibility data. Apparent digestibility coefficients for dry matter, crude protein and energy calculated using acid-insoluble ash were higher (84.0 %, 93.2 % and 93.0 %, respectively) than those using chromic oxide (55.7 %, 79.1 % and 78.2 %) and titanium dioxide (58.6 %, 79.7 % and 80.5 %). The magnitude of variation in digestibility coefficients obtained using acid-insoluble ash was always lower than that obtained with the other markers. Therefore, acid-insoluble ash was preferred as a dietary marker. Using the above protocol, protein and amino acid digestibility of some animal and plant protein ingredients were evaluated in a series of experiments. The first trial compared the apparent digestibility coefficients of some animal products included as single protein source in the test diets. Apparent protein digestibility values were 84.5 %, 83.8 %, 85.8 % and 83.1 % for fishmeal-prime, fishmeal-standard, poultry meal and pork meal, respectively. Apparent digestibility coefficients for poultry meal were comparable to those of fishmeal, which indicate its potential as a substitute for fishmeal in the diets of A. japonicus. The second trial determined the apparent coefficients of plant and animal protein sources included at 30 % into a practical reference diet (70 %). Apparent protein digestibility ranged from 92.4 % in sunflower meal to 85.5 % in corn gluten meal. Soybean meal is a promising feed ingredient in A. japonicus due to the high apparent digestibility of its protein (92.0 %) and essential amino acid digestibility (mean average 91.4 %). A fundamental assumption in fish feed formulation is that the digestibility of nutrients is additive, i.e., digestibility of a nutrient in one ingredient does not interact with the digestibility of the same nutrient in another ingredient. In the third trial, additivity of feed ingredients was tested using pork meal and poultry meal. The results indicate that the apparent digestibility coefficient of animal protein ingredients could be calculated from compound diets to accurately determine protein and amino acid digestibility in A. japonicus, and possibly other carnivorous fish species. Dietary essential amino acid requirements were determined for juvenile A. japonicus in two trials. A dose-response study was conducted using crystalline lysine to determine the optimal requirement of dietary lysine for A. japonicus. Optimal dietary lysine was estimated at 31.7 g kg-¹ dry diet, corresponding to 73.5 g kg-¹ of dietary protein, based on specific growth rate and broken-line segmented regression analyses. Dietary requirements for other essential amino acids ranged from 22 g kg-¹ (histidine) to 71 g kg-¹ (leucine) crude protein. The results of the present study provided a research tool that could be used to assess and verify the conclusions of earlier dietary work on A. japonicus and in further studies to develop least cost diet formulations for this species. The study also adds to the knowledge of the nutritional requirements of A. japonicus by providing information on the digestibility of plants and animal protein ingredients. It also contributes to future dietary research for this species because this study determines, for the first time, the most suitable methods for investigating the digestibility of raw materials for A. japonicus.
- Full Text:
- Date Issued: 2017
- Authors: Adesola, Abidemi Adejoke
- Date: 2017
- Subjects: Amino acids in animal nutrition , Fishes -- Feeding and feeds , Argyrosomus japonicus , Argyrosomus , Argyrosomus japonicus -- Nutrition , Argyrosomus -- Nutrition , Argyrosomus japonicus -- Feeding and feeds , Argyrosomus -- Feeding and feeds
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/32140 , vital:24014
- Description: Important to the evaluation of potential feed ingredients for inclusion in fish diets should be their digestibility and amino acid requirement so that feeds can be formulated on a digestible basis rather than a gross nutrient basis. This thesis established techniques for faecal collection, the validity of digestibility markers, it determined apparent digestibility coefficients for various novel feed ingredients, and it established the optimal lysine requirement for Argyrosomus japonicus, which was used to estimate each of the essential amino acid requirements by using the ideal protein concept. There were no significant differences in dry matter apparent digestibility coefficients when faeces were collected by stripping (77.0 %), dissection (80.1 %) or settlement (83.5 %). Faecal collection by the settlement method produced the most reliable digestibility data. Apparent digestibility coefficients for dry matter, crude protein and energy calculated using acid-insoluble ash were higher (84.0 %, 93.2 % and 93.0 %, respectively) than those using chromic oxide (55.7 %, 79.1 % and 78.2 %) and titanium dioxide (58.6 %, 79.7 % and 80.5 %). The magnitude of variation in digestibility coefficients obtained using acid-insoluble ash was always lower than that obtained with the other markers. Therefore, acid-insoluble ash was preferred as a dietary marker. Using the above protocol, protein and amino acid digestibility of some animal and plant protein ingredients were evaluated in a series of experiments. The first trial compared the apparent digestibility coefficients of some animal products included as single protein source in the test diets. Apparent protein digestibility values were 84.5 %, 83.8 %, 85.8 % and 83.1 % for fishmeal-prime, fishmeal-standard, poultry meal and pork meal, respectively. Apparent digestibility coefficients for poultry meal were comparable to those of fishmeal, which indicate its potential as a substitute for fishmeal in the diets of A. japonicus. The second trial determined the apparent coefficients of plant and animal protein sources included at 30 % into a practical reference diet (70 %). Apparent protein digestibility ranged from 92.4 % in sunflower meal to 85.5 % in corn gluten meal. Soybean meal is a promising feed ingredient in A. japonicus due to the high apparent digestibility of its protein (92.0 %) and essential amino acid digestibility (mean average 91.4 %). A fundamental assumption in fish feed formulation is that the digestibility of nutrients is additive, i.e., digestibility of a nutrient in one ingredient does not interact with the digestibility of the same nutrient in another ingredient. In the third trial, additivity of feed ingredients was tested using pork meal and poultry meal. The results indicate that the apparent digestibility coefficient of animal protein ingredients could be calculated from compound diets to accurately determine protein and amino acid digestibility in A. japonicus, and possibly other carnivorous fish species. Dietary essential amino acid requirements were determined for juvenile A. japonicus in two trials. A dose-response study was conducted using crystalline lysine to determine the optimal requirement of dietary lysine for A. japonicus. Optimal dietary lysine was estimated at 31.7 g kg-¹ dry diet, corresponding to 73.5 g kg-¹ of dietary protein, based on specific growth rate and broken-line segmented regression analyses. Dietary requirements for other essential amino acids ranged from 22 g kg-¹ (histidine) to 71 g kg-¹ (leucine) crude protein. The results of the present study provided a research tool that could be used to assess and verify the conclusions of earlier dietary work on A. japonicus and in further studies to develop least cost diet formulations for this species. The study also adds to the knowledge of the nutritional requirements of A. japonicus by providing information on the digestibility of plants and animal protein ingredients. It also contributes to future dietary research for this species because this study determines, for the first time, the most suitable methods for investigating the digestibility of raw materials for A. japonicus.
- Full Text:
- Date Issued: 2017
Evaluation of groundwater potential using geological and geophysical methods in the University of Fort Hare Alice Campus, Eastern Cape Province of South Africa
- Adesola, Gbenga Olamide https://orcid.org/0000-0002-4151-5305
- Authors: Adesola, Gbenga Olamide https://orcid.org/0000-0002-4151-5305
- Date: 2022-04
- Subjects: Groundwater , Geology, Structural -- South Africa , Geographical Information Systems
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22490 , vital:52344
- Description: Geological and geophysical methods were used to evaluate the groundwater potential in University of Fort Hare (Alice campus), Eastern Cape Province of South Africa. Methodologies adopted for obtaining these results included a comprehensive literature review, thin section analysis, scanning electron microscopy, Geographical Information Systems (GIS), remote sensing and geophysical investigations (magnetic survey and vertical electrical sounding). The geology of the study area belongs to the Balfour Formation, which forms part of the Beaufort Group in the Karoo Supergroup. The rocks within the study area are composed majorly of sandstone and mudstone. Lineaments were automatically extracted using the PCI Geomatica 2018 software. Fifteen samples were collected at various locations within the study area and were analyzed using the petrographic microscope while others were analyzed with the Scanning Electron Microscopic (SEM) combined with an Energy dispersive x-ray spectrometry. The results show that the rocks are fractured, porous and contained minerals such as quartz, feldspar, calcite, mica and clay minerals. The occurrence of these fractures helps to improve the groundwater storage capacity in the study area. Out of the twenty seven (27) rock samples collected in the field, ten (10) rock samples were selected for densities (dry, wet and grain densities) and porosity measurements in the laboratory. The rocks density values range from 2.5763 – 2.6978 g/cm3. The average porosities of the rocks range from 0.85 – 2.56 percent. The density of the sandstone ranges from 2.5908 – 2.6820 g/cm3 whilst the porosity range from 0.85 – 2.02 percent. The density of the mudstone ranges from 2.5763 – 2.6978 g/cm3 whilst the porosity ranges from 1.84 – 2.56 percent. About 8458 magnetic measurements were taken at about 20 m spacing along linear and non-linear paths and road. A variety of magnetic maps were generated. Several magnetic highs were observed and the linear highs were interpreted to be due to dolerite dykes whilst the broader high zones were inferred to be due to dolerite sills. These Karoo dolerites intruded the sediments at various depths and must have fractured the sediments causing them to be more porous and permeable. The depth slices of magnetic data reveal that near surface magnetic bodies occur within the depth of approximately 19 m from the surface while deep seated ones occur as deep as 31 m and maybe deeper. The knowledge of the dolerite intrusions enabled the location of drilling targets for groundwater. Electrical resistivity data were collected at 28 sites using the Schlumberger array and a maximum cable length (250 m) from the centre point which achieved a maximum depth penetration of about 70 m to 162 m. The results from 1D modelling using WINRESIST software showed that the vertical electric sounding curves are composed of HA and HK curve-types, which show four geoelectric layers. The resistivity of the first layer which is the topmost layer has values ranging from 20 - 5752 Ωm and the thickness is between 0.4 – 1.8 m. The second layer which consists of clay, mudstone and sandstone has resistivity values varying from 3 - 51 Ωm and thickness varying from 0.8 – 17.5 m. The third layer which is interpreted to be the aquiferous layer of the study area is made up majorly of sandstone with resistivity that varies from 136 – 352 Ωm and thickness range from 9.9 – 143.9 m. The fourth layer of resistivity varying from 44 to 60428 Ωm is made up of mudstone and sandstone, which are in some places intruded by dolerites. Groundwater potential is favourably high in some of the areas investigated. Furthermore, the results of the research indicated that secondary porosity is the main porosity for the reservoir rocks in the study area. , Thesis (MSc) -- Faculty of Science and Agriculture, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Adesola, Gbenga Olamide https://orcid.org/0000-0002-4151-5305
- Date: 2022-04
- Subjects: Groundwater , Geology, Structural -- South Africa , Geographical Information Systems
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/22490 , vital:52344
- Description: Geological and geophysical methods were used to evaluate the groundwater potential in University of Fort Hare (Alice campus), Eastern Cape Province of South Africa. Methodologies adopted for obtaining these results included a comprehensive literature review, thin section analysis, scanning electron microscopy, Geographical Information Systems (GIS), remote sensing and geophysical investigations (magnetic survey and vertical electrical sounding). The geology of the study area belongs to the Balfour Formation, which forms part of the Beaufort Group in the Karoo Supergroup. The rocks within the study area are composed majorly of sandstone and mudstone. Lineaments were automatically extracted using the PCI Geomatica 2018 software. Fifteen samples were collected at various locations within the study area and were analyzed using the petrographic microscope while others were analyzed with the Scanning Electron Microscopic (SEM) combined with an Energy dispersive x-ray spectrometry. The results show that the rocks are fractured, porous and contained minerals such as quartz, feldspar, calcite, mica and clay minerals. The occurrence of these fractures helps to improve the groundwater storage capacity in the study area. Out of the twenty seven (27) rock samples collected in the field, ten (10) rock samples were selected for densities (dry, wet and grain densities) and porosity measurements in the laboratory. The rocks density values range from 2.5763 – 2.6978 g/cm3. The average porosities of the rocks range from 0.85 – 2.56 percent. The density of the sandstone ranges from 2.5908 – 2.6820 g/cm3 whilst the porosity range from 0.85 – 2.02 percent. The density of the mudstone ranges from 2.5763 – 2.6978 g/cm3 whilst the porosity ranges from 1.84 – 2.56 percent. About 8458 magnetic measurements were taken at about 20 m spacing along linear and non-linear paths and road. A variety of magnetic maps were generated. Several magnetic highs were observed and the linear highs were interpreted to be due to dolerite dykes whilst the broader high zones were inferred to be due to dolerite sills. These Karoo dolerites intruded the sediments at various depths and must have fractured the sediments causing them to be more porous and permeable. The depth slices of magnetic data reveal that near surface magnetic bodies occur within the depth of approximately 19 m from the surface while deep seated ones occur as deep as 31 m and maybe deeper. The knowledge of the dolerite intrusions enabled the location of drilling targets for groundwater. Electrical resistivity data were collected at 28 sites using the Schlumberger array and a maximum cable length (250 m) from the centre point which achieved a maximum depth penetration of about 70 m to 162 m. The results from 1D modelling using WINRESIST software showed that the vertical electric sounding curves are composed of HA and HK curve-types, which show four geoelectric layers. The resistivity of the first layer which is the topmost layer has values ranging from 20 - 5752 Ωm and the thickness is between 0.4 – 1.8 m. The second layer which consists of clay, mudstone and sandstone has resistivity values varying from 3 - 51 Ωm and thickness varying from 0.8 – 17.5 m. The third layer which is interpreted to be the aquiferous layer of the study area is made up majorly of sandstone with resistivity that varies from 136 – 352 Ωm and thickness range from 9.9 – 143.9 m. The fourth layer of resistivity varying from 44 to 60428 Ωm is made up of mudstone and sandstone, which are in some places intruded by dolerites. Groundwater potential is favourably high in some of the areas investigated. Furthermore, the results of the research indicated that secondary porosity is the main porosity for the reservoir rocks in the study area. , Thesis (MSc) -- Faculty of Science and Agriculture, 2022
- Full Text:
- Date Issued: 2022-04