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Industry 4.0 and Skills Deficiencies in the HRM Function: Case Study of the HRM Department of a selected organisation in Cape Town

  • Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
  • Date: 2021
  • Subjects: Personel Management Industry 4.0 Article
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/8095 , vital:61395 , xlink:href="https://www.abacademies.org/articles/industry-40-and-skills-deficiencies-in-the-hrm-function-case-study-of-the-hrm-department-of-a-selected-organization-in-cape-town-10664.html"
  • Description: The study was formulated to tap into the future of HRM given the disruptions arising from the Covid-119 pandemic as well as the progression of the global technological environment to the fourth industrial revolution. The aim of the study was to: the Covid-19 induced HRM practices underpinning future organizational competitiveness. A literature review strategy was adopted to achieve the study objective. The study established seven emerging themes to inform HRM practices for the competitiveness of organizations in future following the Covid-19 disturbances. These themes are: primacy of HRM, increased cyber influences, digitalization, remote HRM, human-machine interface skills, human-organisation strategic links as well as human-technology interface competencies. Based on the study findings, the study recommended HRM departments to move to HR 4.0 through the adoption of industry 4.0 technologies, increased automation, and digitalization as well as strengthen virtualization systems.
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  • Date Issued: 2021

Interaction of silver nanoparticles with catechol O-methyltransferase: Spectroscopic and simulation analyses

  • Authors: Usman, Aminu , Lobb, Kevin A , Pletschke, Brett I , Whiteley, Christopher G , Wilhelmi, Brendan S
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/451095 , vital:75018 , xlink:href=" https://doi.org/10.1016/j.bbrep.2021.101013"
  • Description: Catechol O-methyltransferase, an enzyme involved in the metabolism of catechol containing compounds, catalyzes the transfer of a methyl group between S-adenosylmethionine and the hydroxyl groups of the catechol. Furthermore it is considered a potential drug target for Parkinson’s disease as it metabolizes the drug levodopa. Consequently inhibitors of the enzyme would increase levels of levodopa. In this study, absorption, fluorescence and infrared spectroscopy as well as computational simulation studies investigated human soluble catechol Omethyltransferase interaction with silver nanoparticles. The nanoparticles form a corona with the enzyme and quenches the fluorescence of Trp143. This amino acid maintains the correct structural orientation for the catechol ring during catalysis through a static mechanism supported by a non-fluorescent fluorophore–nanoparticle complex. The enzyme has one binding site for AgNPs in a thermodynamically spontaneous binding driven by electrostatic interactions as confirmed by negative ΔG and ΔH and positive ΔS values. Fourier transform infrared spectroscopy within the amide I region of the enzyme indicated that the interaction causes relaxation of its β− structures, while simulation studies indicated the involvement of six polar amino acids. These findings suggest AgNPs influence the catalytic activity of catechol O-methyltransferase, and therefore have potential in controlling the activity of the enzyme.
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  • Date Issued: 2021

Introducing DerivatizeME and its Application in the Augmentation of a Natural Product Library

  • Authors: Sigauke, Lester T , Taştan Bishop, Özlem , Lobb, Kevin A
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/451120 , vital:75020 , xlink:href="https://doi.org/10.1142/S2737416521500101"
  • Description: The large chemical space universe can be traversed by screening libraries of compounds that possess novel medicinally relevant chemistries, properties and complexity criteria. These libraries can be populated with the use of exhaustive, de novo approaches or inspired, combinatorial approaches. By assuming that natural products within screening libraries may be classified as a source of feedstock for populating virtual libraries, they can act as scaffolds upon which exhaustive approaches may be used in exploring chemical space. In order to achieve this, we have built DerivatizeME as a tool that enumerates derivatives of query compounds in order to evaluate their relevance for further assessment and development. This technique was applied to natural products present in the South African natural compound database (SANCDB). By expanding the chemical space of SANCDB compounds through the generation of SANCDB derivatives, we were able to graduate some natural products that were in undesirable regions of medicinally relevant chemical space, to acceptable regions of this chemical space. These modified scaffolds are available for further development, testing and evaluation in a manner similar to natural product driven focused libraries. The natural product parent is used, through its derivatives, instead of being discarded from screening protocols. This approach has the potential to enhance the efficiency of the natural product library in providing successful hits, amplifying the potential that they possess to access both novel bioactives and privileged scaffolds which may have otherwise been overlooked.
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  • Date Issued: 2021

Investigating popular CNN architectures for plant disease detection

  • Authors: Poole, Louise C , Brown, Dane L
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/465168 , vital:76579 , xlink:href="https://ieeexplore.ieee.org/abstract/document/9519341"
  • Description: Food production and food security have become increasingly important due to climate change and rising population numbers. One method to prevent crop loss is to develop a system to allow for early, efficient and accurate identification of plant diseases. CNNs often outperform previously popular machine learning algorithms. There are many existing CNN architectures. We compared and analysed the popular state-of-the-art architectures, namely ResNet, GoogLeNet and VGG, when trained for plant disease classification. We found that ResNet performed the best on the balanced Mendeley Leaves and PlantVillage datasets, obtaining 91.95% and 95.80% accuracy respectively. However, the ResNet architecture was relatively computationally expensive and slow to train. GoogLeNet obtained accuracies very close to those of ResNet with 89.35% and 94.59% achieved on the Mendeley Leaves and PlantVillage datasets respectively and could be considered a less computationally expensive alternative.
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  • Date Issued: 2021

Knowledge of formal and informal regulations affecting wild plant foraging practices in urban spaces in South Africa

  • Authors: Garekae, Hesekia , Shackleton, Charlie M
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/403221 , vital:69935 , xlink:href="https://doi.org/10.1016/j.forpol.2021.102659"
  • Description: Although foraging wild plants is commonly perceived to be synonymous with rural areas, it is now increasingly recognized in urban areas. Notwithstanding, the regulations conditioning access to and rights to foraging in urban green spaces have seldom been examined. This study explored the formal and informal regulations governing access to and defining rights to forageable plant resources in the towns of Potchefstroom and Thabazimbi, South Africa. A random sample of 374 households was considered for the survey, complemented by in-depth interviews with 26 participants. Foraging occurred in a variety of public and private spaces, with the frequency of access differing with the type of space. The majority of the respondents were unaware of formal and informal regulations governing access to and use of urban landscapes. Recognizing foraging activities in urban landscapes is a fundamental step toward fostering active community involvement in the management and production of urban green spaces.
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  • Date Issued: 2021

Leadership Styles and Employee Job Satisfaction: A Case of Head of Departments in Walter Sisulu UniversityMonitoring and Management Mechanisms on Stress in HEI in Eastern Cape Province in South Africa: Critical Review

  • Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
  • Date: 2021
  • Subjects: Educational Leadership Education (Higher) College department heads Article
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/8082 , vital:61392 , xlink:href="https://www.abacademies.org/articles/leadership-styles-and-employee-job-satisfaction-a-case-of-head-of-departments-in-walter-sisulu-university-10942.html"
  • Description: This study was based on the relationship between the leadership styles of Academic head of Department and employee job satisfaction at the Higher Education Institution (HEI). In so doing, the study was based on the following questions: What is the relationship between leadership styles of HODs and employee job satisfaction in a Higher Education institution in the Eastern Cape Province of South Africa. A purposive sampling technique was utilised to select the participants, which comprised 80 academic staff members to which the researcher hand-delivered 80 questionnaires. The study employed a quantitative method to collect and analyse data. The study found that Perceptions on the leadership styles of academic HODs at the HEI are varied. No clear pattern emerged on what leadership styles are prevalent. The relationship between leadership styles and employee job satisfaction appears to be nonlinear. Job satisfaction is a phenomenon that is determined by many factors, not simply leadership styles.
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  • Date Issued: 2021

LTSP Client Image Maintenance: Utilising a Virtualisation Player to Support Educators to Directly Manage Classroom Applications

  • Authors: Zvidzayi, Tichaona , Terzoli, Alfredo , Dlodlo, Nomusa
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/474364 , vital:77705 , xlink:href="https://ieeexplore.ieee.org/abstract/document/9576935"
  • Description: This paper reports on the work done in the Siyakhula Living Lab (SLL) schools, a joint project between the Universities of Rhodes and Fort Hare. The computing infrastructure in SLL is based on the Linux Terminal Server Project (LTSP), which allows client computers to boot from a centralised server and in some cases offload the computation to the server. Most SLL educators find it difficult to manage classroom applications using the GNU/Linux tools directly. So, educators had to rely on others to add applications for their classroom activity, reducing their sense of being in control and making processes longer and less flexible. A recent development in LTSP has introduced the possibility of setting the boot image for the clients within a virtual machine. This paper explores this option in detail and proposes that educators switch to a virtualisation player to manage applications they want to use in the classroom.
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  • Date Issued: 2021

Malnutrition in children under the age of 5 years in a primary health care setting

  • Authors: Kaswa, Ramprakash , Govender, Indiran , Rangiah, Selvandran , Nzaumvila, Doudou
  • Date: 2021
  • Subjects: Obesity Malnutrition Dietary supplements Article
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/7260 , vital:53106 , xlink:href="https://doi.org/10.4102/safp.v63i1.5337"
  • Description: In this study, we outlined the types of malnutrition amongst children, the causes of malnutrition intervention at the primary health care level and some recommendations to alleviate childhood malnutrition in South Africa. Keywords: obesity; severe acute malnutrition; individual factors; community level factors; dietary intervention.
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  • Date Issued: 2021

Management approach of patients with violent and aggressive behaviour in a district hospital setting in South Africa

  • 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.
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  • Date Issued: 2021

Maternal health care services in waiting mothers’ shelters: the case of Mawadza village in Bonda, Manicaland, Zimbabwe

  • Authors: Muchabveyo, Brenda Hamufari
  • Date: 2021
  • Subjects: Pregnant women Zimbabwe Manicaland Province , Women's shelters Zimbabwe Manicaland Province , Maternal health services Zimbabwe Manicaland Province , Integrative medicine , Childbirth Social aspects Zimbabwe Manicaland Province
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/476912 , vital:78017 , DOI 10.21504/10962/476912
  • Description: This study explores the experiences and perceptions of expectant mothers during prenatal, intra-, and postpartum care. It focuses on expectant mother‘s use or non-use of a waiting mothers' shelter within a medical pluralistic village within a context where hospitals and maternal health care facilities are not proximate. Special focus was on Mawadza village in the Mutasa district in Manicaland Province of Zimbabwe. A sample of 48 participants was used for collecting data in this study. The sample consisted of 15 women some of whom were expectant mothers in the waiting mothers‘ shelter (11) and others had used (4) the shelter once or twice since 2015. Participants were drawn mainly from Mawadza village and Bonda Mission Hospital while others were from the district and provincial offices of the Ministry of Health and Child Care of Zimbabwe. The study adopted a qualitative research methodology, which employed in-depth interviews; key informant interviews (KIIs) and focus group discussions (FGDs) as the main data gathering strategies. In-depth interviews were conducted with the expectant mothers and those who had formerly used the shelter since 2015, while, key informant interviews were conducted with the hospital staff members, traditional healers and the midwives from Mawadza village. Focus group discussions were also conducted with both male and female community members from Mawadza village. The study carried out face to face interviews and notes were handwritten and transcribed at the end of each day. Data coding was used to analyse data. The paradigms and theoretical underpinnings of the study were influenced by the symbolic interactionist theory. The theory made it possible to understand the social processes of pregnancy and childbirth in the waiting mothers' shelter due to its interpretive approach to social research and the legitimacy it places on the social interaction and meanings that social actors place on interactions in their environments. The study documented the ways pregnancy and childbirth are perceived, understood, and experienced in Mawadza village within the context of medical pluralism. In Mawadza village, pregnancy and childbirth are highly embedded in the cultural beliefs of the local people, hence, treated with importance and assumed important symbolic meanings. On the contrary, the waiting mothers‘ shelter as a biomedical facility handles pregnancy and childbirth from a biomedical approach, basing its practices and operations on pure science. Expectant mothers who await labour in this facility are therefore involved in several biomedical activities during prenatal, intra- and post-partum care in the waiting mothers‘ shelter. The need to access skilled birth attendants and the criminalisation of home births in Mawadza village have been the major reasons that influence the expectant mothers to use the waiting mothers‘ shelter. Nevertheless, factors such as medical pluralism, child care, and family commitments, lack of understanding of the importance of the waiting mothers‘ shelter, lack of privacy in the shelter, and cost of food and utilities during the expectant mothers' stay in this facility among others are factors that deter expectant mothers from using the waiting mothers' shelter. Lack of practice of bodily agency where practices common in preparation for childbirth such as opening the birth canal which is not accepted was also reported among common problems that discourage expectant mothers from preferring use of the shelters. The study also revealed that the community is involved in the operations of the waiting mothers‘ shelter, although, the involvement is gendered since there are more women involved as compared to men. The study concluded that even biological processes such as pregnancy and childbirth can only be fully understood within a social context given the different meanings which are attached to the various aspects of the childbirth process by the various actors such as expectant mothers, mothers, biomedical practitioners, traditional healers and communities in Mawadza village. Also, in a medical pluralistic village, the different health care providers who deal with pregnant women do not necessarily conflict as evidenced by the complementary role of these two (complementary insofar as they achieve collectively desired outcomes, albeit in parallel and (mutually) exclusive means) in caring for women during pregnancy and childbirth. , Thesis (PhD) -- Faculty of Humanities, Sociology, 2021
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  • Date Issued: 2021

MDM-TASK-web: MD-TASK and MODE-TASK web server for analyzing protein dynamics

  • Authors: Sheik Amamuddy, Olivier , Glenister, Michael , Tshabalala, Thulani , Tastan Bishop, Özlem
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/476574 , vital:77938 , xlink:href="https://doi.org/10.1016/j.csbj.2021.08.043"
  • Description: The web server, MDM-TASK-web, combines the MD-TASK and MODE-TASK software suites, which are aimed at the coarse-grained analysis of static and all-atom MD-simulated proteins, using a variety of non-conventional approaches, such as dynamic residue network analysis, perturbation-response scanning, dynamic cross-correlation, essential dynamics and normal mode analysis. Altogether, these tools allow for the exploration of protein dynamics at various levels of detail, spanning single residue perturbations and weighted contact network representations, to global residue centrality measurements and the investigation of global protein motion. Typically, following molecular dynamic simulations designed to investigate intrinsic and extrinsic protein perturbations (for instance induced by allosteric and orthosteric ligands, protein binding, temperature, pH and mutations), this selection of tools can be used to further describe protein dynamics. This may lead to the discovery of key residues involved in biological processes, such as drug resistance. The server simplifies the set-up required for running these tools and visualizing their results. Several scripts from the tool suites were updated and new ones were also added and integrated with 2D/3D visualization via the web interface. An embedded work-flow, integrated documentation and visualization tools shorten the number of steps to follow, starting from calculations to result visualization. The Django-powered web server (available at https://mdmtaskweb.rubi.ru.ac.za/) is compatible with all major web browsers. All scripts implemented in the web platform are freely available at https://github.com/RUBi-ZA/MD-TASK/tree/mdm-task-web and https://github.com/RUBi-ZA/MODE-TASK/tree/mdm-task-web
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  • Date Issued: 2021

Mildly elevated thyroid-stimulating hormone is associated with endothelial dysfunction and severe preeclampsia among pregnant women with insufficient iodine intake in Eastern Cape province, South Africa

  • Authors: Businge, Charles Bitamazire , Longo-Mbenza, Benjamin , Kengne, Andre Pascal
  • Date: 2021
  • Subjects: Preeclampsia Iodine deficiency diseases Endothelial cells Article
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/6908 , vital:52565 , xlink:href="https://10.1080/07853890.2021.1947520"
  • Description: Background Preeclampsia and hypothyroidism are associated with endothelial dysfunction. Iodine deficiency is a risk factor for subclinical hypothyroidism in pregnancy. However, there is a paucity of data on the relationship between iodine nutrition state in pregnancy, the degree of endothelial dysfunction, and the risk of preeclampsia. Methods Ninety-five normotensive pregnant women, 50 women with preeclampsia with no severe features, and 50 women with severe preeclampsia were enrolled into the current study from the maternity units of Nelson Mandela Academic Hospital and Mthatha Regional Hospitals in Eastern Cape Province, South Africa. Urinary iodine concentration (UIC), serum markers of thyroid function, aortic augmentation index, and pulse wave velocity (PWV) were compared. Results Median UIC was 167.5, 127.7, and 88.5 µg/L, respectively for normotensive pregnant women, those with preeclampsia and severe preeclampsia (p = .150). Participants with severe preeclampsia had significantly higher median thyroid-stimulating hormone (TSH) and oxidized LDL than normotensive and preeclamptic women without severe features (respectively 3.0, 2.3, and 2.3 IU/L; 1.2, 1.0, and 1.0 IU/L, p  less  .05). The median Aortic augmentation index was 7.5, 19.0, and 21.0 (p  less  .001), and the pulse wave velocity 5.1, 5.7, and 6.3, respectively for normotensive, preeclampsia, and severe preeclampsia participants (both p  less  .001). In linear regressions, TSH, age, and hypertensive disease were independent predictors of elevated PWV. Conclusion Upper normal-range TSH levels in women with severe preeclampsia were associated with markers of endothelial dysfunction. The low UIC and trend towards the elevation of thyroglobulin suggest that inadequate iodine intake may have increased TSH levels and indirectly caused endothelial dysfunction. Keywords: Preeclampsia, Iodine deficiency, Elevated thyroid-stimulating hormone, Pulse wave velocity, Endothelial dysfunction
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  • Date Issued: 2021

Mitigating the Implications of Covid 19 on the Academic Project at Walter Sisulu University in South Africa: A Proposed Framework for Emergency Remote Teaching and Learning

  • Date: 2021
  • Subjects: South Africa Covid-19 (deseases) Web-based instruction Education (Higher) Information technology Computer-assisted instruction Article
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/7644 , vital:54734 , ("https://DOI:10.24085/jsaa.v9i1.1427")
  • Description: Walter Sisulu University (WSU) in South Africa, like other universities worldwide, is faced with the challenges associated with the outbreak of the Covid‑19 pandemic. The challenge has changed our day‑to‑day lives, including the way we interact and conduct business. In the midst of this, WSU has had to change the way learning and teaching occurs. Traditional face‑to‑face tuition had to be adapted by moving to the online mode of teaching and learning to both minimise the time lost in the academic project and protect staff and students from the devastating effects of the virus. This article reflects the actions taken by the University and describes its pilot‑project approach to online learning and those processes it has put in place to ensure its effective implementation. While it is accepted that switching to an online mode of teaching and learning can facilitate flexibility in space and time, the reality is that the majority of students at WSU – mainly due to their geographical and socio‑economic environments – experience daily challenges ranging from poor network coverage, lack of internet connectivity, lack of electricity and other socio‑economic impediments that make online learning stressful or beyond their reach. In this article, we present a model that could be used by higher education institutions (HEIs) to respond to Covid‑19 in the short term. The proposed model is underpinned by a framework that caters for students who are readily able to access online learning, students with intermittent access to online facilities and finally, students who cannot access online education. First, we provide a brief description of online learning, highlighting the challenges presented to teaching and learning by this approach. We argue that our context and education policies present additional problems that militate against the adoption of online strategies by most HEIs. In the final instance, we present a framework that is better suited to our context and can be used during and after the lockdown. Data were collected using online questionnaires with both structured and open‑ended questions from both lecturers and students to determine their experiences with the testing project. Lastly, we draw conclusions based on the findings of the study.
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  • Date Issued: 2021

Mobile attendance based on face detection and recognition using OpenVINO

  • Authors: Brown, Dane L
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/465201 , vital:76582 , xlink:href="https://ieeexplore.ieee.org/abstract/document/9395836"
  • Description: The OpenVINO toolkit enables versatile computer vision with an Intel® Movidius ™ Neural Compute Stick 2 connected to a Raspberry Pi. This small portable platform provides new opportunities for innovative solutions in computer vision applications and beyond. This paper investigates its feasibility for mobile attendance systems for settings such as classrooms or other scenarios that require headcount or roll call. Related studies of face-based systems are explored, while the advantages of the proposed system are highlighted. Although there are some positioning constraints, the proof-of-concept system processes an approximate average of five faces per second. That means it can take attendance in a lecture room of 90 students in about 18 seconds. A recognition accuracy of 98.1% with an f-score of 96.9% was yielded on a private classroom dataset captured with a modest RPi camera. These promising results were achieved using a tiny ResNet-18 architecture, producing significantly better results than MobileNet. Furthermore, it outperformed the recognition accuracy of other ‘lightweight’ methods used in the literature that do not run off embedded devices on publicly available datasets.
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  • Date Issued: 2021

Modulation of the optical properties of chiral porphyrin dimers by introducing bridged chiral amide-bonds

  • Authors: Qin, Mingfeng , Zhang, Zhen , Zhu, Weihua , Mack, John , Soy, Rodah C , Nyokong, Tebello , Liang, Xu
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/190815 , vital:45031 , xlink:href="https://doi.org/10.1142/S1088424620500492"
  • Description: The d/l-enantiomers of a series of three Zn(II)tetraarylporphyrin dimers were synthesized and isolated by incorporating a bridging amide-bonded xanthene moiety at the para-position of one of the meso-aryl rings. The electronic structures and optical properties were modulated by incorporating chiral amino acid moieties into the amide-bonding moieties of the xanthene bridge that contain methyl, tolyl and 2-methylindole substituents. A cofacial dimer was formed in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) resulting in a significant red shift of the B band, due to a relative destabilization of the HOMO, which has large MO coefficients on the pyrrole nitrogens. The sign sequences observed in the B band region of the CD spectra due to the presence of the chiral amino acid moieties were modified due to this change in geometry. Significant CD intensity is also observed in the B band region of the CD spectra of anion radical species during in situ spectroelectrochemical measurements.
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  • Date Issued: 2021

Monitoring and Management Mechanisms on Stress in HEI in Eastern Cape Province in South Africa: Critical Review

  • Authors: Asoba, Samson Nambei , Patricia, Nteboheng Mefi
  • Date: 2021
  • Subjects: Teachers--Job stress , Ill-Discipline of Learners , Middle school education -- Parent participation
  • Language: English
  • Type: text , article , Article
  • Identifier: http://hdl.handle.net/11260/8068 , vital:61393 , xlink:href="https://www.abacademies.org/articles/monitoring-and-management-mechanisms-on-stress-in-hei-in-eastern-cape-province-in-south-africa-critical-review-10636.html"
  • Description: Stress is a global phenomenon that affects everyone regardless of gender, resources and environment. Although this phenomenon is well researched, teachers’ experiences of stress remains a worrying challenge particularly to schools’ effectiveness. This study sought to establish how monitoring and management mechanism that can assist teachers to cope with stress challenges. These are some of the recommendation: that the school disciplinary committee should be trained in various disciplinary measures that may be implemented in the school to curb learner ill-discipline and lack of commitment, that working relationship should be built between schools and the Department of Basic Education, motivational speakers and educational counsellors should meet with all learners on a regular basis to motivate them to have high desire for and interest in education and to build their self-confidence in the classroom, providing all the schools with healthy environment in classrooms, provision of learning and teaching materials to all schools, schools should set up an effective school-parents partnership in order to promote a safe drug and alcohol free environment, employ enough teachers in all secondary schools and the Department of Basic Education at district level should make room for stress management workshops for teachers.
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  • Date Issued: 2021

Morton Feldman-Morton Feldman, Morton Feldman Piano. Philip Thomas

  • Authors: Fourie, William
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/484405 , vital:78903 , xlink:href="https://doi.org/10.1017/S0040298220000741"
  • Description: ‘The scale of what is actually being represented, whether it be of the whole or of the part, is a phenomenon unto itself.’ Feldman’s words from his famous 1981 essay, ‘Crippled Symmetry’, echoed in my ears as I sat down to listen to Philip Thomas’s monumental new record of the composer’s piano music. It spans over four decades of the composer’s singular creative engagement with the instrument and has a total run-time of nearly six hours. The five-disc box set also contains a rich 52-page essay on Feldman’s piano music, which broaches a wide range of issues ranging from abstract, interpretative ideas regarding touch and decay to more practical discussions around notation.
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  • Date Issued: 2021

Muco-adhesive clarithromycin-loaded nanostructured lipid carriers for ocular delivery: Formulation, characterization, cytotoxicity and stability

  • Authors: Makoni, Pedzisai A , Khamanga, Sandile M , Walker, Roderick B
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/183150 , vital:43916 , xlink:href="https://doi.org/10.1016/j.jddst.2020.102171"
  • Description: Topical ophthalmic formulations are the preferred approach to treat the anterior segment of the eye as it is a non-invasive therapeutic approach. The ocular bioavailability of drugs is generally limited, due to the presence of impervious anatomical barriers and low residence time and contact with the target tissue. Optimization of clarithromycin-loaded nanostructured lipid carriers using Design of Experiments was undertaken. Manufacture of nanostructured lipid carriers was achieved using hot emulsification ultrasonication. Formulation and process parameters were successfully identified following screening and subsequently optimized using Tween® 20, as a stabilizer. Muco-adhesive properties that could potentially increase ocular residence time, in vitro clarithromycin release and cytotoxicity against HeLa cells were evaluated. Short term stability studies of the optimized lipidic formulations was assessed at 4 °C and 22 °C. The optimized formulation exhibited muco-adhesive properties under stationary conditions assessed using Laser Doppler Anemometry, sustained release of API over 24 h under in vitro conditions. In vitro cytotoxicity studies revealed that the NLC were less cytotoxic to HeLa cells in comparison to pure API. The results suggest that the optimized carriers may have the potential to enhance precorneal retention, increase ocular availability and permit dose reduction or permit use of a longer dosing frequency.
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  • Date Issued: 2021

Naked Eye and Colorimetric Detection of Cyanide with a 1, 3‐Diethyl‐2‐thiobarbituric Acid Substituted Ferrocene Chemosensor

  • Authors: Babu, Balaji , Mack, John , Nyokong, Tebello
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/190567 , vital:45006 , xlink:href="https://doi.org/10.1002/slct.202100163"
  • Description: A 1,3-diethyl-2-thiobarbituric-acid-substituted ferrocene (FET) has been evaluated for its cyanide sensing ability by UV-visible absorption spectroscopy and other characterization methods. FET provides a ratiometric colorimetric chemosensor for the CN− anion detection in 1 : 1 DMSO/H2O (v/v) solution. The addition of CN− results in an immediate color change from dark blue to pale orange that is visible to the naked eye. Mechanism studies and molecular modelling with TD-DFT calculations demonstrate that nucleophilic addition of CN− to an electrophilic sp2-hybridized carbon atom blocks charge transfer from the ferrocene ring complex to the thiobarbituric acid moiety. The FET sensor exhibits excellent selectivity for CN− and a limit of detection of 0.2 μM.
  • Full Text:
  • Date Issued: 2021

Nano Co-Crystal Embedded Stimuli-Responsive Hydrogels: A Potential Approach to Treat HIV/AIDS

  • Authors: Witika, Bwalya A , Stander, Jessé-Clint , Smith, Vincent J , Walker, Roderick B
  • Date: 2021
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/183137 , vital:43915 , xlink:href="https://doi.org/10.3390/pharmaceutics13020127"
  • Description: Currently, the human immunodeficiency virus (HIV) that causes acquired immunodeficiency syndrome (AIDS) can only be treated successfully, using combination antiretroviral (ARV) therapy. Lamivudine (3TC) and zidovudine (AZT), two compounds used for the treatment of HIV and prevention of disease progression to AIDS are used in such combinations. Successful therapy with 3TC and AZT requires frequent dosing that may lead to reduced adherence, resistance and consequently treatment failure. Improved toxicity profiles of 3TC and AZT were observed when combined as a nano co-crystal (NCC). The use of stimuli-responsive delivery systems provides an opportunity to overcome the challenge of frequent dosing, by controlling and/or sustaining delivery of drugs. Preliminary studies undertaken to identify a suitable composition for a stimulus-responsive in situ forming hydrogel carrier for 3TC-AZT NCC were conducted, and the gelation and erosion time were determined. A 25% w/w Pluronic® F-127 thermoresponsive hydrogel was identified as a suitable carrier as it exhibited a gelation time of 5 min and an erosion time of 7 days. NCC-loaded hydrogels were evaluated using in vitro dissolution and cytotoxicity assays. In vitro dissolution undertaken using membrane-less diffusion over 168 h revealed that 3TC and AZT release from NCC-loaded hydrogels was complete and followed zero-order kinetic processes, whereas those loaded with the micro co-crystal and physical mixture were incomplete and best described using the Korsmeyer–Peppas kinetic model. The release of AZT and 3TC from the physical mixture and MCC-loaded gel exhibited a value for n of 0.595 for AZT release from the physical mixture and 0.540 for the MCC technology, whereas the release exponent for 3TC was 0.513 for the physical mixture and 0.557 for the MCC technology indicating that diffusion and erosion controlled 3TC and AZT release. In vitro cytotoxicity assay data revealed that the addition of NCC to the thermoresponsive hydrogel resulted in an improved cell viability of 88.0% ± 5.0% when compared to the cell viability of the NCC of 76.9% ± 5.0%. The results suggest that the use of a thermoresponsive nanosuspension may have the potential to be delivered as an intramuscular injection that can subsequently increase bioavailability and permit dose reduction and/or permit use of a longer dosing frequency.
  • Full Text:
  • Date Issued: 2021
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