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Variations of biochemical parameters along a transect in the Southern Ocean, with special emphasis on volatile halogenated organic compounds

  • Authors: Abrahamsson, K , Bertilsson, S , Chierici, M , Fransson,A , Froneman, P William , Lorén, A , Pakhomov, Evgeny A
  • Date: 2004
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/491491 , vital:80496 , xlink:href="https://doi.org/10.1016/j.dsr2.2004.09.004"
  • Description: A number of parameters of biogeochemical interest were monitored along a north–southerly transect (S 43–S 63°) in the Atlantic Sector of the Southern Ocean from the 8th to the 20th of December 1997. Changes in total dissolved inorganic carbon (CT) and total alkalinity (AT) were mostly dependent on temperature and salinity until the ice edge was reached. After this point only a weak correlation was seen between these.
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  • Date Issued: 2004

Point of Sales (POS) Terminals for Bank Service Delivery, the needs for Management of Information Security: A case of Nigeria’s Banking Sectors

  • Authors: Adebisi, Abiodun A , Salamntu, Lumka T P , Iwundu, Mary P
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/488202 , vital:79850 , xlink:href="10.1109/ICTAS59620.2024.10507146"
  • Description: A point of sale (POS) system is a valuable technological tool that has successfully replaced the traditional cash register banking system and has maintained constantly evolving tech-driven solutions. User security and trust perception are paramount to the success of the financial services rendered using the POS terminals. In Nigeria, the POS system has revolutionised the banking sector as millions of "unbanked citizens" can comfortably perform cash deposits and withdrawals, pay bills, and do other financial services without physically stepping into the banking hall. The management of information security of point of sales terminals was studied using the theory of the Technology Acceptance Model (TAM) by looking at behavioural intentions as a factor that leads people to use available technology. A mixed research method was adopted to allow the collection of quantitative and qualitative data for the study. The collected data were analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM) and revealed that customers prefer POS systems to the banking hall because of their availability, flexibility, ease of use, error tolerance, and service efficiency.
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  • Date Issued: 2024

Conjugation of mono-substituted phthalocyanine derivatives to CdSe@ ZnS quantum dots and their applications as fluorescent-based sensors

  • Authors: Adegoke, Oluwasesan , Nyokong, Tebello
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/189842 , vital:44936 , xlink:href="https://doi.org/10.1016/j.synthmet.2013.11.016"
  • Description: Unsymmetrically substituted derivatives of aluminium amino phthalocyanines were synthesized for the first time, fully characterized and conjugated to CdSe@ZnS quantum dots (QDs). The conjugates were employed as fluorescence-based sensors for anion sensing. Among the anions that enhanced the fluorescence of the probe, fluoride ion was chosen as the test ion to test the efficacy of the probe. Förster resonance energy transfer from the QDs to the phthalocyanine was observed as an indication for the fluorescence quenching of the QDs upon binding to the phthalocyanine. The fluorescence of the linked QDs was progressively enhanced, and linearly proportional to increasing concentrations of fluoride ion. The type of substituent attached to the phthalocyanine ring influenced the efficiency of fluorescence enhancement. The proposed nanoprobe has been employed to detect fluoride ion in cell culture medium and tap water.
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  • Date Issued: 2014

Unsymmetrically substituted nickel triazatetra-benzcorrole and phthalocynanine complexes

  • Authors: Adegoke, Oluwasesan , Nyokong, Tebello
  • Date: 2014
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/189818 , vital:44934 , xlink:href="https://doi.org/10.1007/s10895-013-1317-4"
  • Description: We report on the design and application of fluorescent nanoprobes based on the covalent linking of L-glutathione-capped CdSe@ZnS quantum dots (QDs) to newly synthesized unsymmetrically substituted nickel mercaptosuccinic acid triazatetra-benzcorrole (3) and phthalocyanine (4) complexes. Fluorescence quenching of the QDs occurred on conjugation to complexes 3 or 4. The nanoprobes were selectively screened in the presence of different cations and Hg2+ showed excellent affinity in “turning ON” the fluorescence of the nanoprobes. Experimental results showed that the sensitivity of QDs-4 towards Hg2+ was much higher than that of QDs-3 nanoprobe. The mechanism of reaction has been elucidated based on the ability of Hg2+ to coordinate with the sulphur atom of the Ni complex ring and apparently “turn ON” the fluorescence of the linked QDs.
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  • Date Issued: 2014

Factors affecting adherence to antiretroviral therapy among pregnant women in theEastern Cape, South Africa

  • 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
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  • Date Issued: 2018

Tuning the physico-electrochemical properties of novel cobalt (II) octa [(3, 5-biscarboxylate)-phenoxy] phthalocyanine complex using phenylamine-functionalised SWCNTs

  • Authors: Agboola, Bolade O , Ozoemena, Kenneth I , Nyokong, Tebello , Fukuda, Takamitsu , Kobayashi, Nagao
  • Date: 2010
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/261692 , vital:53435 , xlink:href="https://doi.org/10.1016/j.carbon.2009.10.023"
  • Description: The integration of phenylamine-functionalised SWCNTs (SWCNT-phenylamine) with a novel cobalt (II) octa[(3,5-biscarboxylate)-phenoxy] phthalocyanine (CoOBPPc) complex has been described. The physical and electrochemical properties of the CoOBPPc-SWCNT-phenylamine hybrid were evaluated using spectroscopy (IR and UV–vis), field emission scanning electron microscopy and electrochemistry (cyclic voltammetry and electrochemical impedance spectroscopy). Integration of SWCNT-phenylamine resulted in the physical transformation of the CoOBCPPc from the usually bluish colour of cobalt phthalocyanine complexes to a beautiful bright green colour. In addition, the heterogeneous electron transfer kinetics and electrocatalytic properties of the CoOBCPPc were greatly enhanced following the attachment of the SWCNT-phenylamine. The potential electrocatalytic application of the hybrid was tested using β-nicotinamide adenine dinucleotide (NADH) as a model biological analyte. Interestingly, the onset oxidation potential of this analyte was significantly reduced (300 mV) by this hybrid compared to the bare electrode.
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  • Date Issued: 2010

The South America tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), spreads its wings in Eastern Africa: distribution and socioeconomic impacts

  • Authors: Aigbedion-Atalor, Pascal O , Hill, Martin P , Zalucki, Myron P , Obala, Francis , Idriss, Gamal E , Midingoyi, Soul-Kifouly G , Chidege, Maneno , Ekesi, Sunday , Mohamed, Samira Abuelgasim
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/423859 , vital:72099 , xlink:href="https://doi.org/10.1093/jee/toz220"
  • Description: Following the arrival of Tuta absoluta Meyrick in the eastern African subregion in 2012, several studies have shown numerous ecological aspects of its invasion. We investigated the impact of T. absoluta on people’s livelihoods across four counties of Kenya. Here, 200 farmers in the country were interviewed in person using semistructured questionnaires. In addition to livelihood surveys, T. absoluta distribution was mapped between 2016 and 2018 to determine its current distribution across four countries (Kenya, Sudan, Tanzania, and Uganda) in the subregion. Albeit a recent invader, T. absoluta is abundant and distributed throughout the subregion and is viewed as the worst invasive alien species of agriculturally sustainable livelihoods by tomato farmers. The arrival of T. absoluta in the subregion has resulted in livelihood losses and increased both the cost of tomato production and frequency of pesticide application. We recommend the implementation of biological control along, with other control measures in an integrated approach, against T. absoluta in the subregion, where its impact on sustainable livelihoods is serious and long-term control strategies are required to curb its detrimental effects.
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  • Date Issued: 2019

Critical indirect effects of climate change on sub-A ntarctic ecosystem functioning

  • Authors: Allan, E Louise , Froneman, P William , Durgadoo, Jonathan V , McQuaid, Christopher D , Ansorge, Isabelle J , Richoux, Nicole B
  • Date: 2013
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/457934 , vital:75696 , xlink:href="https://doi.org/10.1002/ece3.678"
  • Description: Sub‐Antarctic islands represent critical breeding habitats for land‐based top predators that dominate Southern Ocean food webs. Reproduction and molting incur high energetic demands that are sustained at the sub‐Antarctic Prince Edward Islands (PEIs) by both inshore (phytoplankton blooms; “island mass effect”; autochthonous) and offshore (allochthonous) productivity. As the relative contributions of these sustenance pathways are, in turn, affected by oceanographic conditions around the PEIs, we address the consequences of climatically driven changes in the physical environment on this island ecosystem. We show that there has been a measurable long‐term shift in the carbon isotope signatures of the benthos inhabiting the shallow shelf region of the PEIs, most likely reflecting a long‐term decline in enhanced phytoplankton productivity at the islands in response to a climate‐driven shift in the position of the sub‐Antarctic Front. Our results indicate that regional climate change has affected the balance between allochthonous and autochthonous productivity at the PEIs. Over the last three decades, inshore‐feeding top predators at the islands have shown a marked decrease in their population sizes. Conversely, population sizes of offshore‐feeding predators that forage over great distances from the islands have remained stable or increased, with one exception. Population decline of predators that rely heavily on organisms inhabiting the inshore region strongly suggest changes in prey availability, which are likely driven by factors such as fisheries impacts on some prey populations and shifts in competitive interactions among predators. In addition to these local factors, our analysis indicates that changes in prey availability may also result indirectly through regional climate change effects on the islands' marine ecosystem. Most importantly, our results indicate that a fundamental shift in the balance between allochthonous and autochthonous trophic pathways within this island ecosystem may be detected throughout the food web, demonstrating that the most powerful effects of climate change on marine systems may be indirect.
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  • Date Issued: 2013

Spatial and temporal patterns in bacterial abundance, production and viral infection in a temporarily open/closed southern African estuary

  • Authors: Allan, E Louise , Froneman, P William
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/491252 , vital:80471 , xlink:href="https://doi.org/10.1016/j.ecss.2007.11.006"
  • Description: The spatial and temporal patterns in bacterial abundance, biomass, production, nanoflagellate abundance and the loss of bacterial production due to viral lysis were investigated in a temporarily open/closed estuary along the eastern seaboard of southern Africa over the period May 2006 to April 2007. Bacterial abundance, biomass and production ranged between 1.00×109 and 4.93×109cellsl−1, 32.43 and 108.59μgCl−1 and 0.01 and 1.99μgCl−1h−1, respectively.
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  • Date Issued: 2008

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

Benthic mapping using local aerial photo interpretation and resident taxa inventories for designing marine protected areas

  • Authors: Aswani, Shankar , Lauer, Matthew
  • Date: 2006
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/439059 , vital:73541 , xlink:href="https://doi.org/10.1017/S0376892906003183"
  • Description: Given the frequent socioeconomic, political and concomitant ecological failures of science-driven marine protected area (MPA) programmes, it is now important to design MPAs by integrating natural and social science research more comprehensively. This study shows how indigenous peoples assisted in the design of MPAs by identifying marine substrates and related resident taxa on aerial photos, information which was then incorporated into a geographical information system (GIS) database, along with dive survey data. Two questions were asked: (1) Is indigenous ecological knowledge accurate enough for mapping the benthos and associated taxa? (2) Is such an approach an appropriate way for assisting in the biological and social design of MPAs in Oceania? Conventional quadrat field dive surveys were used to measure the accuracy of substrate identification by local informants and a visual survey was used to test hypotheses formulated from local knowledge regarding the spatial distribution and relative abundance of non-cryptic species within certain benthic habitats. Equivalence rates between indigenous aerial photo interpretations of dominant benthic substrates and in situ dive surveys were 75–85% for a moderately detailed classification scheme of the benthos, which included nine locally-defined abiotic and biotic benthic classes for the MPA seabed. Similarly, the taxa inventory showed a strong correspondence between the qualitative predictions of local fisherfolk and the quantitative analysis of non-cryptic species distribution, including their relative abundance and geophysical locations. Indigenous people's predictions about the presence or absence of fish in different benthic habitats corresponded 77% and 92% of the time (depending on scoring schema) with in situ visual measurements. These results demonstrate how incorporating local knowledge of benthic heterogeneity, existing biological communities, and particular spatio-temporal events of biological significance into a GIS database can corroborate the production of scientifically reliable base resource maps for designing MPAs in an environmentally and culturally sound fashion. This participatory approach was used to design and then establish MPAs in the Roviana and Vonavona region of the Western Solomon Islands. Under appropriate conditions, interdisciplinary work can complement the design of scientific fishery management and biodiversity conservation prescriptions for coastal Oceania.
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  • Date Issued: 2006

Biosynthesis of silver nanoparticles from Acacia mearnsii De Wild stem bark and its antinociceptive properties

  • Authors: Avoseh, Opeyemi N , Oyedeji, Opeoluwa O , Aremu, Olukayode , Nkeh-Chungag, Benedicta N , Songca, Sandile P , Oyedeji, Adebola Omowunmi , Mohan, Sneha , Oluwafemi, Oluwatobi S
  • Date: 2017
  • Subjects: Metal nanoparticles , Acacia mearnsii , Nociceptive pain
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/1528 , vital:37774 , https://doi.org/10.1080/17518253.2017.1287310
  • Description: The biosynthesis of silver nanoparticles (Ag-NPs) using the hydrosol extract of the dry stem bark of Acacia mearnsii as reducing and capping agents, and their antinociceptive properties are hereby reported. By varying the temperature and reaction time, the temporal evolution of the optical and morphological properties of the as-synthesized material was investigated. The NPs were characterized by UV–visible absorption spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS) and x-ray diffractometry (XRD) The optical analyses show that the position of the maximum surface plasmon resonance (SPR) peak is red-shifted as the reaction temperature decreased. The TEM micrographs show that the as-synthesized Ag-NPs are spherical while the X-ray diffraction shows that the material is highly crystalline with face-centered cubic structures. The anti-inflammatory efficacy, analyzed by the formalin model, indicates that the as-synthesized Ag-NPs are very effective, with an inhibition rate of about 76%.
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  • Date Issued: 2017

The association between HIV tri-therapy with the development of Type-2 Diabetes Mellitus in a rural South African district: A case-control study

  • Authors: Bam, Nokwanda E , Mabunda, Sikhumbuzo A , Ntsaba, Jafta , Apalata, Teke , Monatshila, Sibusisu C , Chitha, Wesile
  • Date: 2020
  • Subjects: Type 2 diabetes , AIDS (Disease) , Rural health
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/11260/4008 , vital:43983 , https://doi.org/10.1371/journal.pone.0244067
  • Description: Combination antiretroviral drugs(cARVs)prolong patients’ lives but are unfortunately thought to increase complications related to metabolic disorders including type-2 Diabetes Mellitus(DM).We sought to confirm the association of cARVs with type-2DM and ascertain the extent of this association in a rural South African setting. A case-control study of 177 (33.33%) cases with HIV/AIDS and type-2 DM were selected and compared with 354 (66.67%) non-DM HIV/AIDS unmatched controls from a rural district of South Africa’s third most populous province (Eastern Cape). Cases were identified from community health centres using the district health information system, and controls were identified using simple random sampling from the same health facilities. Odds Ratios (OR), together with 95% confidence intervals, were calculated for all the univariable and multivariable logistic analyses. This study found that cARVs significantly increased the occurrence of type-2 DM among HIV patients. Patients on protease inhibitors (PIs) were at least 21 times significantly more likely to be diabetic than those on the fixed dose combination (FDC); those on stavudine (D4T) and zidovudine (AZT) were 2.45 times and 9.44 times respectively more likely to be diabetic than those on FDC. The odds of diabetes increased by more than three-folds for those who had been on antiretroviral drugs for more than 6 years.
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  • Date Issued: 2020

Nutrient-mediated silica uptake from agricultural runoff in invasive floating macrophytes: implications for biological control

  • Authors: Baso, Nompumelelo C , Delport, Garyn A , Coetzee, Julie A
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/424803 , vital:72185 , xlink:href="https://doi.org/10.1007/s10750-020-04344-5"
  • Description: Silica (Si) plays a significant role in alleviating the effects of biotic and abiotic stressors in many plants, especially in an agricultural context. With increased use of Si-based fertilisers, understanding plant responses to the addition of Si to their environment, particularly aquatic environments, is important. We investigated how two invasive macrophytes, Eichhornia crassipes and Pistia stratiotes, responded to different nutrient and Si concentrations, in the presence and absence of herbivory. Both species incorporated Si into their foliage, but uptake of Si did not increase under high nutrient availability but rather decreased, especially in P. stratiotes. Plant quality (i.e. C:N) for both weed species was affected more by nutrient concentrations than Si content, and the addition of Si had a negative effect on plant growth. Eichhornia crassipes increased daughter plant production under high Si conditions, while P. stratiotes plants showed no reproductive response to increased Si except in low nutrient conditions where reproduction was reduced. The addition of Si resulted in increased biomass of E. crassipes, while P. stratiotes was unaffected. These results highlight that runoff of Si from fertiliser alter aquatic plant–insect interactions, which has consequences for biological control.
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  • Date Issued: 2020

An appraisal of the recruitment and selection process of the judiciary (chief justice) in Zimbabwe

  • Authors: Bazana, Sandiso , Jackson, Charlene
  • Date: 2019
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/453722 , vital:75280 , xlink:href="https://www.ajol.info/index.php/ijhss/article/view/192901"
  • Description: Societies that have accepted the notion of liberal modern democracy respect the role of the judges or the judiciary in making such democracies a success. As such, the drafting of the 2013 Constitution of Zimbabwe was a particularly significant event because, amongst other things, it set out the judicial selection process to be followed in the future. Following the recent appointment of the new chief justice (Justice Malaba, appointed in 2016) there has been controversy regarding the Zimbabwean judicial recruitment and selection appointment process. While some renowned legal practitioners expressed the opinion that the process itself was somewhat commendable, the reality is that there were some major flaws, which must be addressed for future judicial selection and appointment. This study analysed documents to appraise the recent recruitment and selection process of the chief justice in Zimbabwe. This study collated data from the Zimbabwe Constitution, Zimbabwe Legal Information Institute, Zimbabwe Case law, legislation and journal articles. The findings from this study suggest that there were some flaws in the last recruitment and selection process of the Chief Justice that were conducted by the Judicial Service Commission. The paper demonstrates some of these flaws. Broadly, the results of this work suggest that the recruitment and selection process require the expertise of those who are skilled in the procedure to do it with utmost proficiency, with limited acrimony and as little hindrance from the public as possible.
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  • Date Issued: 2019

Landscape drivers of mammal habitat use and richness in a protected area and its surrounding agricultural lands

  • Authors: Bellón, Beatriz , Henry, Dominic AW , Renaud, Pierre-Cyril , Roque, Fabio de O , Santos, Cyntia Cavalcante , Melo, Isabel , Arvor, Damien , de Vos, Alta
  • Date: 2022
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/415873 , vital:71296 , xlink:href="https://doi.org/10.1016/j.agee.2022.107989"
  • Description: Protected areas (PAs) are key to conserving biodiversity and ecosystem services globally, but their effectiveness increasingly depends on the ability of the surrounding agricultural areas to support biodiversity and secure connectivity at the landscape level. This requires monitoring the broader multi-use landscapes in which PAs exist and identifying the landscape characteristics that support rich, functional wildlife communities. Here, we investigated the species richness and habitat use patterns of a mammal community in relation to different landscape variables and land use and land cover (LULC) types in a PA and its surrounding agricultural lands in the Cerrado. We first used a hierarchical multi-species occupancy model with input camera trap data and eight landscape variables (vegetation productivity, phenology, and heterogeneity, distance to water, roads and settlements, and the PA, slope, and elevation) to estimate the species richness and habitat use of 29 mammal species across the landscape. We then analyzed the relationships between the species richness and habitat use and the landscape variables at the site level, as well as the distribution of species at the landscape level in relation to the different natural and agricultural LULC types.
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  • Date Issued: 2022

Puma (Puma concolor) sex influences diet in southwest New Mexico

  • Authors: Bernard, Kelly M T , Perry, Travis W , Mgqatsa, Nokubonga
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/462647 , vital:76322 , xlink:href="https://doi.org/10.3398/064.083.0201"
  • Description: Puma (Puma concolor) is a wide-ranging, large felid species, and site-specific research on its diet is important for local management. Like the diets of other large felids, puma diets may differ between sex due to size dimorphism and between seasons due to changes in prey vulnerability and availability. We investigated the influence of sex and season on puma diet in southwest New Mexico in terms of prey species and size categories. Pumas (10 males, 6 females) were tracked with GPS collars for an average of one year per individual between February 2008 and July 2020. Puma location was recorded every 2 hours between 19:00 and 7:00, and kill sites were identified by a minimum of 2 GPS fixes occurring within 100 m and 100 hours of the first fix. Pumas specialized on mule deer (Odocoileus hemionus) and elk (Cervus elaphus) but also preyed upon a range of other species of different sizes. The probability of making a medium-sized kill such as a mule deer was higher for females than for males, while the probability of making an extra-large kill, such as an elk, was considerably greater for males than for females. There was substantial variation in prey species and size categories killed by individual pumas, particularly of smaller-sized prey like collared peccary (Pecari tajacu) and skunks (e.g., Spilogale gracilis, Mephitis mephitis). Our findings concur with previous research on the importance of mule deer and elk in puma diet, demonstrate individual variation in prey killed, and may have management implications.
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  • Date Issued: 2023

The Southern African Program on Ecosystem Change and Society: an emergent community of practice

A Practical Use for AI-Generated Images

  • Authors: Boby, Alden , Brown, Dane L , Connan, James
  • Date: 2023
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/463345 , vital:76401 , xlink:href="https://link.springer.com/chapter/10.1007/978-3-031-43838-7_12"
  • Description: Collecting data for research can be costly and time-consuming, and available methods to speed up the process are limited. This research paper compares real data and AI-generated images for training an object detection model. The study aimed to assess how the utilisation of AI-generated images influences the performance of an object detection model. The study used a popular object detection model, YOLO, and trained it on a dataset with real car images as well as a synthetic dataset generated with a state-of-the-art diffusion model. The results showed that while the model trained on real data performed better on real-world images, the model trained on AI-generated images, in some cases, showed improved performance on certain images and was good enough to function as a licence plate detector on its own. The study highlights the potential of using AI-generated images for data augmentation in object detection models and sheds light on the trade-off between real and synthetic data in the training process. The findings of this study can inform future research in object detection and help practitioners make informed decisions when choosing between real and synthetic data for training object detection models.
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  • Date Issued: 2023

The double burden of treating traumatic stress in low-resource communities: experiences and perspectives of non-specialist health workers in South Africa

  • Authors: Booysen, Duane D , Kagee, Ashraf
  • Date: 2022
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/454132 , vital:75312 , xlink:href="https://doi.org/10.1177/0081246320984051 "
  • Description: Considering the global trend towards the dissemination and implementation of trauma-focused treatments in the majority of the world, it is imperative to ascertain the contextual factors which affect the treatment of traumatic stress, especially in low- and middle-income countries characterised by ongoing adversity such as poverty and increased levels of trauma exposure. We explored the experiences of non-specialist health workers whose work involved providing trauma-focused services in low-resource communities in South Africa. Participants (n = 18) worked at four non-governmental organisations in the Eastern Cape and Western Cape of South Africa. Semi-structured individual interviews were conducted and analysed using a phenomenologically informed thematic analysis. Two superordinate themes were identified, namely, adjusting to trauma-focused work and trauma in the social context. Five themes that made up the superordinate themes were Encountering Trauma Narratives, Support and Resilience, Going the Extra Mile, Helplessness, and Social Factors. The findings are not only in keeping with the psychological risks of trauma-focused work (e.g., vicarious traumatisation) but also highlighting the impact of the social context on the provision of trauma-focused work. Participants reported experiencing an added burden of helplessness due to social factors, such as poverty and high levels of trauma exposure, which affect the process of treating traumatic stress in low-resource settings. We discuss how these findings can contribute to efforts to implement trauma-focused services in low- and middle-income countries.
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  • Date Issued: 2022
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