Socioeconomic and geographic variations in antenatal care coverage in Angola: further analysis of the 2015 demographic and health survey
- Authors: Shibre, Gebretsadik , Zegeye, Betregiorgis , Idriss-Wheeler, Dina , Ahinkorah, Bright Opoku , Oladimeji, Olanrewaju , Yaya, Sanni
- Date: 2023
- Subjects: Prenatal care , Mothers -- Mortality , Health surveys
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/4489 , vital:44125 , https://doi.org/10.1186/s12889-020-09320-1
- Description: In African countries, including Angola, antenatal care (ANC) coverage is suboptimal and maternal mortality is still high due to pregnancy and childbirth-related complications. There is evidence of disparities in the uptake of ANC services, however, little is known about both the socio-economic and geographic-based disparity in the use of ANC services in Angola. The aim of this study was to assess the extent of socio-economic, urban-rural and subnational inequality in ANC coverage in Angola. We analyzed data from the 2015 Angola Demographic and Health Survey (ADHS) using the World Health Organization (WHO) Health Equity Assessment Toolkit (HEAT) software. The analysis consisted of disaggregated ANC coverage rates using four equity stratifiers (economic status, education, residence, and region) and four summary measures (Difference, Population Attributable Risk, Ratio and Population Attributable Fraction). To measure statistical significance, an uncertainty interval (UI) of 95% was constructed around point estimates. The study showed both absolute and relative inequalities in coverage of ANC services in Angola. More specifically, inequality favored women who were rich (D = 54.2, 95% UI; 49.59, 58.70, PAF = 43.5, 95% UI; 40.12, 46.92), educated (PAR = 19.9, 95% UI; 18.14, 21.64, R = 2.14, 95% UI; 1.96, 2.32), living in regions such as Luanda (D = 51.7, 95% UI; 43.56, 59.85, R = 2.64, 95% UI; 2.01, 3.26) and residing in urban dwellings (PAF = 20, 95% UI; 17.70, 22.38, PAR = 12.3, 95% UI; 10.88, 13.75). The uptake of ANC services were lower among poor, uneducated, and rural residents as well as women from the Cuanza Sul region. Government policy makers must consider vulnerable subpopulations when designing needed interventions to improve ANC coverage in Angola to achieve the 2030 Sustainable Development Goal of reducing global maternal mortality ratio to 70 deaths per 100,000 live births.
- Full Text:
- Date Issued: 2023
Epidemiology, risk factors and molecular analysis of carbapenem-resistant Enterobacteriaceae (CRE) in Mthatha, Eastern Cape, South Africa:
- Authors: S.D.Vasaikar , P.Hanise , D.T.Abaver
- Date: 2021
- Subjects: Epidemiology Carbapenem-resistant Enterobacteriaceae Mthatha
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3129 , vital:43143 , xlink:href="https://doi.org/10.3390/f10060467"
- Description: Abstract text. Background: The emergence of carbapenem resistance in Enterobacteriaceae is an important threat to global health. Reported outcomes of infections with carbapenem-resistant Enterobacteriaceae (CRE) are poor. Commonly used antibiotics are generally inactive against CRE. Therefore, timely detection of CRE is of paramount importance. This study aimed to investigate the resistance genes responsible for CRE in Mthatha and to identify risk factors. Methods and materials: Study design – Prospective cohort study. Study period – 23 April to 27 September 2019. Setting – Eastern Cape province, SA. Study population – All adult and paediatric CRE patients. CRE case definition according to CDC 2018. ID and AST-bioMérieux Vitek 2 system. Detection of the blaOXA-48, blaKPC, blaNDM, and blaVIM by the RESIST-4 OKNV assay (Coris). Patients were interviewed to determine risk factors associated with CRE. Results: Forty-four non-duplicate CRE patients were identified during the study period from microbiology lab at NMAH. Enterobacteriaceae species: K. pneumoniae 22 (61.4%), E. cloacae 10 (22.7%), E. coli 2 (4.5%) and K. oxytoca, P. rettgeri and M. morganii 1 each (4.3%). Adult patient 29 (65.9%0 and paediatric 15 (34.1%). Race: all black patients except one white. CRE genes-blaOXA-48 22 (50%), blaNDM 8 (18.2%), two isolates (4.5%) with both blaOXA and blaNDM. We did not find any blaKPC and blaVIM in our setting and 12 (27.2%) isolates were negative for all OKNV. Outcomes: Demised 18 (40.9%), still admitted in the ward 1 (2.3%), discharged home on basis of clinical grounds 22 (50%) and 3 (6.8%) were transferred back to the district hospitals. HAI in 27 (61.4%) with VAP 8, HABSI 8, CAUTI 5, SSI 3 and CLABSI in 3. Risk factors for CRE acquisition were antibiotic exposure 25 (58.7%), ICU stay 7 (15.9%), received medical care in last 6 months 35 (79.6%) and none travelled outside RSA. HIV positive – 19 (43.2%). Conclusion: In out setting our CRE mortality rate is 40.9%, common CRE genotypes are blaOXA-48 and blaNDM. K. pneumoniae is the most common CRE-producing Enterobacteriaceae and antibiotic exposure is an important risk factor in Mthatha and surrounding areas.
- Full Text:
- Date Issued: 2021
Sociodemographic inequities associated with participation in leisure-time physical activity in sub-Saharan Africa: an individual participant data meta-analysis
- Authors: Longo-Mbenza, Benjamin , Barr, Anna Louise , Partap, Uttara , Young, Elizabeth H , Agoudavi, Kokou , Balde, Naby , Kagaruki, Gibson B , Mayige, Mary T , Mutungi, Gerald , Mwalim, Omar , Wesseh, Chea S , Bahendeka, Silver K , Guwatudde, David , Jørgensen, Jutta M Adelin , Bovet, Pascal , Motala, Ayesha A , Sandhu, Manjinder S
- Date: 2020-06-15
- Subjects: Recreation. Use of leisure time , Occupational therapy , Health surveys
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/3378 , vital:43337 , https://doi.org/10.1186/s12889-020-08987-w
- Description: Leisure-time physical activity (LTPA) is an important contributor to total physical activity and the focus of many interventions promoting activity in high-income populations. Little is known about LTPA in subSaharan Africa (SSA), and with expected declines in physical activity due to rapid urbanisation and lifestyle changes we aimed to assess the sociodemographic differences in the prevalence of LTPA in the adult populations of this region to identify potential barriers for equitable participation. A two-step individual participant data meta-analysis was conducted using data collected in SSA through 10 population health surveys that included the Global Physical Activity Questionnaire. For each sociodemographic characteristic, the pooled adjusted prevalence and risk ratios (RRs) for participation in LTPA were calculated using the random effects method. Between-study heterogeneity was explored through meta-regression analyses and tests for interaction. Across the 10 populations (N = 26,022), 18.9% (95%CI: 14.3, 24.1; I2 = 99.0%) of adults (≥ 18 years) participated in LTPA. Men were more likely to participate in LTPA compared with women (RR for women: 0.43; 95%CI: 0.32, 0.60; P less than 0.001; I2 = 97.5%), while age was inversely associated with participation. Higher levels of education were associated with increased LTPA participation (RR: 1.30; 95%CI: 1.09, 1.55; P = 0.004; I2 = 98.1%), with those living in rural areas or self-employed less likely to participate in LTPA. These associations remained after adjusting for time spent physically active at work or through active travel. In these populations, participation in LTPA was low, and strongly associated with sex, age, education, self-employment and urban residence. Identifying the potential barriers that reduce participation in these groups is necessary to enable equitable access to the health and social benefits associated with LTPA.
- Full Text:
- Date Issued: 2020-06-15
"Knowing With": New Rhodes Board Navigates Collaboration, Intimacy, and Solidarity
- Authors: Baasch, Rachel M , Fọlárànmí, Stephen , Koide, Emi , Kakande, Angelo , Simbao, Ruth K
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147514 , vital:38645 , https://doi.org/10.1162/afar_a_00523
- Description: Rhodes University (or UCKAR), based in Makhanda, South Africa, joined the African Arts editorial consortium in 2016 and its first journal issue—vol. 50, no. 2—was published in 2017. Initially the board was run by Ruth Simbao, with the aim of developing collaborations with other scholars, particularly those based on the African continent and within the global south (Simbao 2017: 1). For the second Rhodes issue (Summer 2018), Simbao worked with Guest Board Member Amanda Tumusiime from Makerere University, and for the third Rhodes issue (Summer 2019) she collaborated with Stephen Folárànmí from Obáfémi Awólówò University, Ilé-Ifè, Nigeria, who at the time was a Postdoctoral Fellow at Rhodes.
- Full Text:
- Date Issued: 2020
'Choice' in women's abortion decision-making narratives: Introducing a supportability approach
- Authors: Mavuso, Jabulile M-J J , Chiweshe, Malvern T , Macleod, Catriona I
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446220 , vital:74482
- Description: Liberal abortion legislation emphasises pregnant persons' autonomous choices in abortion decision-making. Within psychological theories, decision-making is understood as largely individual, rational and cognitive, with various factors affecting women's1 abortion decision-making. In this study, purposively recruited from three sites in South Africa and three sites in Zimbabwe, 25 and 18 women, respectively, participated in narrative interviews which were analysed using thematic analysis and a supportability framework. Participants' narratives constructed continuation of the pregnancy as a 'non-option, abortion emerging as the only solution. Economic resources, gender norms and partnerships, and the undesirability of the pregnancy meant the pregnancy was unsupportable at micro- and macro-levels, and sometimes despite parenting being desired by the women. A supportability framework offers opportunities to understand reproductive decision-making as imbricated in the circumstances of the pregnancy which render it (un)supportable, therefore opening up or closing down particular decisions. This framework enables a necessary shift, towards systemic understandings of decision-making, and a possible reduction in abortion-related stigma.
- Full Text:
- Date Issued: 2020
(Unused) potentials of educators’ covert language policies at public schools in Limpopo, South Africa:
- Authors: Kretzer, Michael M , Kaschula, Russell H
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/174679 , vital:42500 , DOI: 10.1039/D0PP00075B
- Description: Language policy is an influencing factor of the educational outcome for pupils in Africa. Colonial languages have been largely used and African Languages are neglected. Despite this, the South African Constitution (1996) declares eleven official languages. However, curricular developments favour Afrikaans and English. To analyse the implementation of the official language policy, we focus on Limpopo Province. Over 1000 questionnaires were answered by teachers. This approach aimed to analyse the language practices and language attitudes of teachers. Schools in Limpopo showed significant differences between the official language policy and the daily language practices. Some teachers implement the official language policy; others use one or more African languages in their oral communications during the lessons in the form of Code Switching.
- Full Text:
- Date Issued: 2020
A career in photophysicochemical and electrochemical properties of phthalocyanine: A Linstead Career Award paper
- Authors: Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186045 , vital:44458 , xlink:href="https://doi.org/10.1142/S1088424620300037"
- Description: This manuscript highlights the author’s contributions to phthalocyanine chemistry, especially the applications based on their electrochemistry and photophysicochemistry. In particular, the use of phthalocyanines as electrocatalysts and photocatalysts is presented. For photocatalysis, photodynamic antimicrobial chemotherapy and pollution control using green technologies are highlighted. For electrocatalysis the phthalocyanines are employed for the detection of pollutants and environmentally important molecules. Phthalocyanines are combined with nanomaterials for improved photocatalysis and electrocatalysis.
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- Date Issued: 2020
A comparative study of the effect of different stabilizers on the critical quality attributes of self-assembling nano co-crystals
- Authors: Witika, Bwalya A , Smith, Vincent J , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183224 , vital:43931 , xlink:href=" https://doi.org/10.3390/pharmaceutics12020182"
- Description: Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used orally to manage HIV/AIDS infection. A pseudo one-solvent bottom-up approach was used to develop and produce nano co-crystals of 3TC and AZT. Equimolar amounts of 3TC dissolved in de-ionized water and AZT in methanol were rapidly injected into a pre-cooled vessel and sonicated at 4 °C. The resultant suspensions were characterized using a Zetasizer. The particle size, polydispersity index and Zeta potential were elucidated. Further characterization was undertaken using powder X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and energy dispersive X-ray spectroscopy scanning electron microscopy. Different surfactants were assessed for their ability to stabilize the nano co-crystals and for their ability to produce nano co-crystals with specific and desirable critical quality attributes (CQA) including particle size (PS) less than 1000 nm, polydispersity index (PDI) less than 0.500 and Zeta potential (ZP) less than −30 mV. All surfactants produced co-crystals in the nanometer range. The PDI and PS are concentration-dependent for all nano co-crystals manufactured while only ZP was within specification when sodium dodecyl sulfate was used in the process.
- Full Text:
- Date Issued: 2020
A comparative study of the photophysicochemical and photodynamic activity properties of meso-4-methylthiophenyl functionalized Sn (IV) tetraarylporphyrins and triarylcorroles
- Authors: Dingiswayo, Somila , Babu, Balaji , Prinsloo, Earl , Mack, John , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186157 , vital:44469 , xlink:href="https://doi.org/10.1142/S1088424620500273"
- Description: Tin(IV) complexes of a 4-methylthiophenyl functionalized porphyrin (1-Sn) and its corrole analogue (2-Sn) were synthesized so that their photophysicochemical properties and photodynamic activities against MCF-7 breast cancer cells could be compared. Singlet oxygen luminescence studies revealed that 1-Sn and 2-Sn have comparable ΦΔΦΔ values in DMF of 0.59 and 0.60, respectively, while the IC5050 values after irradiation of MCF-7 cells for 30 min with a Thorlabs 625 nm LED (432 J · cm−2)−2) were determined to be 12.4 and 8.9 μμM. The results demonstrate that the cellular uptake of 2-Sn and its molar absorptivity at the irradiation wavelength play a crucial role during in vitro cytotoxicity studies.
- Full Text:
- Date Issued: 2020
A comparison of three models used to determine water fluxes over the Albany Thicket, Eastern Cape, South Africa:
- Authors: Palmer, Anthony R , Ezenne, G I , Choruma, D J , Gwate, O , Mantel, Sukhmani K , Tanner, Jane L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150047 , vital:38934 , https://doi.org/10.1016/j.agrformet.2020.107984
- Description: The Albany Thicket (AT) biome contains outstanding global biodiversity as well as the potential to achieve carbon credits associated with water-efficient Crasslucean acid metabolism (CAM). Understanding the water fluxes in the AT is crucial to determining carbon (C) sequestration rates and water-use efficiency. Despite large variation in water fluxes across the AT, only a few studies have been conducted in this region with their results validated against short periods of observed data. This study aims to evaluate three models of water fluxes over AT against data from an eddy covariance (EC) system active from October 2015 to May 2018. ET was modelled using the BioGeoChemistry Management (BGC-MAN) model, a biophysical model (Penman-Monteith-Leuning (PML)) and a remotely-sensed product (MOD16), and their results compared with that from the EC system.
- Full Text:
- Date Issued: 2020
A leopard's favourite spots: habitat preference and population density of leopards in a semi-arid biodiversity hotspot
- Authors: Mann, Gareth K H , O'Riain, M Justin , Parker, Daniel M
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148584 , vital:38752 , https://doi.org/10.1016/j.jaridenv.2020.104218
- Description: Leopards (Panthera pardus) are the only free-ranging large predators to still occur naturally throughout much of Africa, but are vulnerable to habitat loss, ecosystem degradation and persecution. We used a systematic camera trap survey covering an area of ∼3100 km2 in the Little Karoo, a semi-arid biodiversity hotspot in South Africa, to assess the impacts of land use and habitat type on leopard density. Camera data were supplemented by opportunistic scat collection to produce a habitat suitability model. We used a habitat suitability model to inform spatially explicit capture-recapture models used to estimate population density. We recorded 152 independent photographs of 27 individually recognizable leopards at 54 camera stations and collected scats from a further 76 locations. Our habitat suitability model showed that primary productivity and vegetation type were the best predictors of leopard habitat suitability. Our best performing population density model allowed for detection and movement of individuals to vary according to sex, and estimated population density at 1.26 (SE ± 0.25) leopards/100 km2.
- Full Text:
- Date Issued: 2020
A mathematics teacher's response to a dilemma: 'I'm supposed to teach them in English but they don't understand'
- Authors: Robertson, Sally-Ann , Graven, Mellony
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148889 , vital:38783 , https://doi.org/10.4102/sajce.v10i1.800
- Description: English is the dominant language in South African schools although it is the home language for less than 10% of the population. Many schools have yet to embrace the Language in Education Policy’s advocacy of additive bilingualism. This has led to a majority of the country’s children learning and being assessed through a language in which they lack proficiency. This article draws on second language teaching and learning theory to make a case for more systematic support for learners’ second language development and for legitimation of use of home language in mathematics classrooms where a different language is the official medium. The article shares empirical data from a South African Grade 4 mathematics teacher’s classroom to illuminate arguments in favour of additive bilingualism.
- Full Text:
- Date Issued: 2020
A multinational study of authors’ perceptions of and practical approaches to writing geography textbooks:
- Authors: Lee, Jongwon , Catling, Simon , Kidman, Gillian , Bednarz, Robert , Krause, Uwe , Martija, Andoni A , Ohnishi, Koji , Wilmot, P Dianne , Zecha, Stefane
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158269 , vital:40168 , https://doi.org/10.1080/10382046.2020.1743931
- Description: Like all school textbooks, geography textbooks are authored. Almost all textbook research in and beyond geography has neglected their authors. This questionnaire-based multinational research project investigated the perceptions of 71 primary and secondary school geography textbook authors from seven countries in five continents. Though not intended as a definitive study, the findings identified several values and areas of expertise which many textbook authors in different countries held to be important for their work.
- Full Text:
- Date Issued: 2020
A new approach to the biological monitoring of freshwater systems: Mapping nutrient loading in two South African rivers, a case study
- Authors: Motitsoe, Samuel N , Hill, Martin P , Avery, Trevor S , Hill, Jaclyn M
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444480 , vital:74244 , https://doi.org/10.1016/j.watres.2019.115391
- Description: Excessive addition of nitrogen (N) has threatened aquatic ecosystems for decades. Traditional water quality and biological monitoring assessment tools are widely used for monitoring nutrient loads and ecosystem health, but most of these methods cannot distinguish between different types and sources of pollution. This is a challenge, particularly when dealing with non-point sources of anthropogenic nitrogen inputs into freshwater systems. Recent laboratory studies using stable isotopic ratios (δ15N and C/N) of aquatic macrophytes (duckweed: Spirodela spp.) have shown successful differentiation and mapping between different N-sources and further, showed abilities to act as early warning indicators for environmental N-loading. Therefore, the aim of this study was to field test the potential of stable isotopic values of transplanted Spirodela spp. to map temporal and spatial N-loading variation and determine the main sources of N-loading in two river systems in the Eastern Cape Province of South Africa, using previously grown, isotopically calibrated and transplanted Spirodela plants, collected over a 13-month sampling period.
- Full Text:
- Date Issued: 2020
A new genus and three new species of South African Cicadettini (Hemiptera Cicadidae Cicadettinae).
- Authors: Sanborn, Allen F , Villet, Martin H
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441261 , vital:73871 , https://www.mapress.com/zt/article/view/zootaxa.4885.4.7
- Description: Ingcainyenzane irhiniensis n. gen., n. sp. and Ingcainyenzane nolukhanyoensis n. gen., n. sp. are described from Eastern Cape and Ingcainyenzane umgeniensis n. gen., n. sp. is described from KwaZulu-Natal, South Africa. Notes on its biology of the species and a key to species of the genus are also provided.
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- Date Issued: 2020
A new indole alkaloid and other constituents from Monodora minor and Uvaria tanzaniae: their antitrypanosomal and antiplasmodial evaluation
- Authors: Christopher, Robert , Mgani, Quintino A , Nyandoro, Stephen S , Rousseau, Amanda L , Isaacs, Michelle , Hoppe, Heinrich C
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429347 , vital:72603 , xlink:href="https://doi.org/10.1080/14786419.2019.1710705"
- Description: Phytochemical investigation of the methanolic extract of Monodora minor Engl. and Diels (Annonaceae) stem bark yielded a new indole (E)-4-(1H-indol-5-yl)-but-3-en-2-one (1), a known indole 5-formyl-1H-indole (2) and an ubiquitous steroid sitosterol (3). The investigations of the methanolic extract of Uvaria tanzaniae Verdc. (Annonaceae) root bark yielded two previously reported C-benzylated dihydrochalcones namely uvaretin (4) and diuvaretin (5). Structures of the isolated compounds were elucidated based on NMR spectroscopy and high resolution electron ionization mass spectrometry (HR-EI-MS) data. All compounds were tested against Trypanosoma brucei brucei and Plasmodium falciparum. At a single concentration (20 μM) in the antitrypanosomal and antiplasmodial assays, compound 4 exhibited remarkable activities against T. brucei brucei and P. falciparum with percentage inhibition of 97.3% and 83.0% respectively, whereas compounds 1, 2, 3 and 5 were inactive. In a dose response antiplasmodial assay compound 4 exhibited moderate activity against P. falciparum with an IC50 value of 7.20 μM.
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- Date Issued: 2020
A novel dimeric exoglucanase (GH5_38)
- Authors: Mafa, Mpho S , Dirr, Heinrich W , Malgas, Samkelo , Krause, Rui W M , Pletschke, Brett I
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193976 , vital:45412 , xlink:href="https://doi.org/10.3390/molecules25030746"
- Description: An exoglucanase (Exg-D) from the glycoside hydrolase family 5 subfamily 38 (GH5_38) was heterologously expressed and structurally and biochemically characterised at a molecular level for its application in alkyl glycoside synthesis. The purified Exg-D existed in both dimeric and monomeric forms in solution, which showed highest activity on mixed-linked β-glucan (88.0 and 86.7 U/mg protein, respectively) and lichenin (24.5 and 23.7 U/mg protein, respectively). They displayed a broad optimum pH range from 5.5 to 7 and a temperature optimum from 40 to 60 °C. Kinetic studies demonstrated that Exg-D had a higher affinity towards β-glucan, with a Km of 7.9 mg/mL and a kcat of 117.2 s−1, compared to lichenin which had a Km of 21.5 mg/mL and a kcat of 70.0 s−1. The circular dichroism profile of Exg-D showed that its secondary structure consisted of 11% α-helices, 36% β-strands and 53% coils. Exg-D performed transglycosylation using p-nitrophenyl cellobioside as a glycosyl donor and several primary alcohols as acceptors to produce methyl-, ethyl- and propyl-cellobiosides. These products were identified and quantified via thin-layer chromatography (TLC) and liquid chromatography–mass spectrometry (LC-MS). We concluded that Exg-D is a novel and promising oligomeric glycoside hydrolase for the one-step synthesis of alkyl glycosides with more than one monosaccharide unit.
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- Date Issued: 2020
A novel gold (I)-mediated intramolecular transamidation of benzoyl thiourea derivatives to form benzamides via dethiocyanation
- Authors: Odame, Felix , Woodcock, Guillaume , Hosten, Eric C , Lobb, Kevin A , Tshentu, Zenixole R
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446988 , vital:74575 , xlink:href="https://doi.org/10.1016/j.jorganchem.2020.121359"
- Description: A novel gold(I)-mediated intramolecular transamidation of thiourea derivatives to yield benzamides via dethiocyanation have been achieved by the reaction of 3-(1,3-benzothiazol-2-yl)-1-(benzoyl)thiourea derivatives in the presence of gold(I) precursors. The compounds have been characterized using IR, NMR, GC-MS and microanalysis. The single crystal XRD of 3-(1,3-benzothiazol-2-yl)-1-(3-bromobenzoyl)thiourea (5), 3-(1,3-benzothiazol-2-yl)-1-(3-methoxybenzoyl)thiourea (6), N-(benzothiazol-2-yl)benzamide (10), N-(benzothiazol-2-yl)-3-chlorobenzamide (11), N-(benzothiazol-2-yl)-4-nitrobenzamide (12), N-(benzothiazol-2-yl)-3-bromobenzamide (14) have been discussed. The novel transformation is thought to proceed by a gold(I)-mediated intramolecular transamidation reaction which releases thiocyanate to yield the benzamide. Density functional theory calculations have been used to support the proposed mechanism for this transformation.
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- Date Issued: 2020
A relational approach to landscape stewardship: Towards a new perspective for multi-actor collaboration
- Authors: Cockburn, Jessica J , Rosenberg, Eureta , Copteros, Athina , Cornelius, Susanna F , Libala, Notiswa , Metcalfe, Liz , van der Waal, Benjamin
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/370098 , vital:66297 , xlink:href="https://doi.org/10.3390/land9070224"
- Description: Landscape stewardship is increasingly understood within the framing of complex social-ecological systems. To consider the implications of this, we focus on one of the key characteristics of complex social-ecological systems: they are relationally constituted, meaning that system characteristics emerge out of dynamic relations between system components. We focus on multi-actor collaboration as a key form of relationality in landscapes, seeking a more textured understanding of the social relations between landscape actors. We draw on a set of ‘gardening tools’ to analyse the boundary-crossing work of multi-actor collaboration. These tools comprise three key concepts: relational expertise, common knowledge, and relational agency. We apply the tools to two cases of landscape stewardship in South Africa: the Langkloof Region and the Tsitsa River catchment. These landscapes are characterised by economically, socio-culturally, and politically diverse groups of actors. Our analysis reveals that history and context strongly influence relational processes, that boundary-crossing work is indeed difficult, and that doing boundary-crossing work in smaller pockets within a landscape is helpful. The tools also helped to identify three key social-relational practices which lend a new perspective on boundary-crossing work: 1. belonging while differing, 2. growing together by interacting regularly and building common knowledge, and 3. learning and adapting together with humility and empathy.
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- Date Issued: 2020
A search for enhanced photodynamic activity against Staphylococcus aureus planktonic cells and biofilms: the evaluation of phthalocyanine–detonation nanodiamond–Ag nanoconjugates
- Authors: Openda, Yolande Ikala , Matshitse, Refilwe , Nyokong, Tebello
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/163825 , vital:41073 , DOI: 10.1039/D0PP00075B
- Description: The present work reports on the synthesis and characterization of novel zinc (2) and indium (3) 2-amino-4-bromophenoxy substituted phthalocyanines (Pcs) along with the self-assembled nanoconjugates formed via π–π stacking interaction onto detonation nanodiamonds (DNDs) to form 2@DNDs and 3@DNDs. 2@DNDs and 3@DNDs were covalently linked to chitosan–silver mediated nanoparticles (CSAg) to form 2@DNDs-CSAg and 3@DNDs-CSAg nanoconjugates. High singlet oxygen quantum yields in DMSO of 0.69 and 0.72 for Pcs alone and 0.90 and 0.92 for 2@DNDs-CSAg and 3@DNDs-CSAg, respectively, were obtained.
- Full Text:
- Date Issued: 2020