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A Genealogy of Puberty Science: Monsters, Abnormals, and Everyone Else

- Pinto, Pedro, Macleod, Catriona I

Authors: Pinto, Pedro , Macleod, Catriona I
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/434065 , vital:73029 , ISBN 9781315142098 , https://doi.org/10.4324/9781315142098
Description: A Genealogy of Puberty Science explores the modern invention of puberty as a scientific object. Drawing on Foucault’s genealogical analytic, Pinto and Macleod trace the birth of puberty science in the early 1800s and follow its expansion and shifting discursive frameworks over the course of two centuries. Offering a critical inquiry into the epistemological and political roots of our present pubertal complex, this book breaks the almost complete silence concerning puberty in critical theories and research about childhood and adolescence. Most strikingly, the book highlights the failure of ongoing medical debates on early puberty to address young people’s sexual and reproductive embodiment and citizenships. A Genealogy of Puberty Science will be of great interest to academics, researchers and postgraduate students in the fields of child and adolescent health research, critical psychology, developmental psychology, health psychology, feminist and gender studies, medical history, science and technology studies, and sexualities and reproduction studies.
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Date Issued: 2019

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A novel axially palladium (II)-Schiff base complex substituted silicon (IV) phthalocyanine

- Sen, Pinar, Nyokong, Tebello

Authors: Sen, Pinar , Nyokong, Tebello
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/186813 , vital:44536 , xlink:href="https://doi.org/10.1016/j.poly.2019.114135"
Description: In this study, a novel silicon(IV) phthalocyanine is reported for the first time as a phthalocyanine derivative bearing axially a palladium(II)-Schiff base complex. The photophysical and photochemical properties of the new Si(IV)Pc, such as absorption, fluorescence, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were measured in DMSO. The new silicon phthalocyanine displayed very low fluorescence, showing efficient intersystem crossing resulting in high triplet and high singlet oxygen quantum yields in DMSO. When compared with the unsubstituted SiPcCl2, the singlet oxygen quantum yield value (UD = 0.47) in relation to the triplet quantum yield (UT = 0.82), which is an important determinant for PDT applications, increased. The photodynamic antimicrobial chemotherapy activity (PACT) of new Si(IV)Pc towards Staphylococcus aureus was determined in comparison to the unsubstituted SiPcCl2. The results of the photodynamic antimicrobial effect study demonstrated that the Pd(II) complex substituted SiPc (5) possesses excellent photodynamic activity with a reduction percentage value of 99.94% and a log red value of 3.26.
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Date Issued: 2019

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A return to common-sense: why ecology needs transcendental realism

- Price, Leigh

Authors: Price, Leigh
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/390324 , vital:68538 , xlink:href="https://doi.org/10.1080/14767430.2019.1580178"
Description: Empirical realist ecologists, such as C. S. Holling, face significant methodological contradictions; for instance, they must cope with the problem that ecological models and theories of climate change, resilience and succession cannot make predictions in open systems. Generally, they respond to this problem by supplementing their empirical realism with transcendental idealism: they therefore say that their models are simply metaphorical or heuristic, that is, 'not true' in that they are not empirical. Thus, they explicitly deny an ontology for what their models are about. Nevertheless, in their practice, ecologists act as if their theories do have an ontology and thus tell us something truthful about the real world. This discrepancy leaves ecology vulnerable to unnecessary critique, such as that climate science is not real science. Transcendental realism offers a solution because it releases ecologists from the requirement to make predictions; but it does so without denying ontology. This provides several advantages to ecologists.
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Date Issued: 2019

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A spatio-temporal, landscape perspective on Acacia dealbata invasions and broader land use and cover changes in the northern Eastern Cape, South Africa

- Gouws, Aidan J, Prof.Shackleton, Charlie M

Authors: Gouws, Aidan J , Prof.Shackleton, Charlie M
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/179670 , vital:43156 , xlink:href="https://doi.org/10.1007/s10661-019-7204-y"
Description: Biological invasions and human land use both have the potential to drastically alter the patterns and processes of landscapes, driving habitat fragmentation and altering natural disturbance regimes. The proliferation of an invasive species depends on composition and configuration of the landscape, as well as the invasiveness of the species. To effectively manage a highly invasive species, such as Acacia dealbata, it is crucial to understand the historical progression of the invasion within the landscape. This study sought to examine the landscape dynamics of biological invasions by tracking the historical spread of A. dealbata and broader land use/land cover (LULC) changes at different spatiotemporal scales in the northern Eastern Cape. A timeseries of aerial photographs were systematically classified according to designated A. dealbata and LULC categories in ArcGIS to track the changes in the extent and rate of spread of A. dealbata. Markedly dynamic, multi-directional, and spatio-temporally variable LULC transitions were observed across the northern Eastern Cape over the last six decades. A. dealbata frequently retained a high proportion of cover over time, and despite the loss of cover to other LULC classes, a net increase in A. dealbata cover occurred as it spread at an overall annual rate of 0.11–0.21%, occupying approximately 8–18% of land cover across all sampled sites by 2013.
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Date Issued: 2019

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Abundance and correlates of the Acacia dealbata invasion in the northern Eastern Cape, South Africa

- Gouws, Aidan J, Shackleton, Charlie M

Authors: Gouws, Aidan J , Shackleton, Charlie M
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/179735 , vital:43165 , xlink:href="https://doi.org/10.1016/j.foreco.2018.09.048"
Description: An increase in the density and biomass of woody invasive plants contributes to the intensification of ecological impacts and can often be met with dissatisfaction by local communities. Despite their reliance on Acacia dealbata as a source of livelihood, villagers in the northern Eastern Cape have expressed concerns about the high densities of the species. This study sought to quantify the current abundance and growth of A. dealbata in selected landscapes in the northern Eastern Cape, around nine villages in rural Matatiele, Mount Fletcher and Maclear. Standard vegetation survey techniques were adopted to quantify the density, biomass and growth rate of A. dealbata. Overall, the average density, biomass and productivity of A. dealbata were estimated at approximately 7000 stems ha−1, 12 Mg ha−1 and 4 Mg ha−1 year−1, respectively. However, the abundance and productivity of A. dealbata were spatially variable between study areas. Acacia dealbata stems experienced significant growth over the period of a single year, contributing to substantial biomass production at the landscape level, despite continued harvest. Furthermore, relatively few biophysical variables were significantly influential correlates with the abundance of A. dealbata. Indeed, the degree of biological invasion can be highly variable across the landscape, shaped by the interaction of local-scale biophysical conditions.
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Date Issued: 2019

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Academic discourse: An inter-disciplinary dialogue

- Martin, J R, Maton, Karl, Doran, Y JR

Authors: Martin, J R , Maton, Karl , Doran, Y JR
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/445880 , vital:74439 , ISBN 9780429280726 , https://www.taylorfrancis.com/chapters/edit/10.4324/9780429280726-1/academic-discourse-martin-karl-maton-doran
Description: This volume has been designed to showcase the cutting-edge of the ever-growing dialogue between systemic functional linguistics (SFL) and Legitimation Code Theory (LCT) and the insights into academic discourse this brings. This opening chapter reviews the foundations of this dialogue and positions the work presented throughout the book within this context. First it steps through the development of SFL work in education, focusing on the register-variable field and how it has been impinged upon by successive developments in Bernstein’s code theory and subsequently LCT. It then introduces how LCT extends and integrates Bernstein’s work to embrace a greater range of phenomena within a more systematic framework. It does this by introducing the dimensions of Specialization and Semantics, and showing the insights these conceptual tools can bring to academic knowledge and academic discourse. Finally, it introduces the chapters that make up the volume and positions them in relation to the ways the LCT–SFL dialogue has driven their understandings. This opening chapter lays the foundations for what is to follow and gives a flavour of energy and explanatory power this dialogue generates.
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Date Issued: 2019

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Addressing geographical bias: A review of Robinia pseudoacacia (black locust) in the Southern Hemisphere

- Martin, Grant D

Authors: Martin, Grant D
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/423937 , vital:72107 , xlink:href="https://doi.org/10.1016/j.sajb.2019.08.01"
Description: Robinia pseudoacacia (black locust) is a medium-sized deciduous tree, native to the Southeastern United States. Due to a number of beneficial attributes, it has been widely planted and become naturalised in several countries. It has one of the largest distributions in Europe of any introduced plant and has increased its distribution into a number of Southern Hemisphere countries. In its introduced range, the species exhibits a number of invasive tendencies, which result in negative environmental and economic impacts. This review presents information on aspects of the plant's biology and ecology with emphasis on its status in the Southern Hemisphere. Topics covered include taxonomy, morphological attributes, distributions, habitats, relationships with other species, growth and development, reproduction, hybridisation, population dynamics, uses, toxicity and the invasive status of the plant in Southern Hemisphere countries This manuscript also provides insights into management options including biological control, which has never been intentionally implemented against this species.
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Date Issued: 2019

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Advances in entomotoxicology: Weaknesses and strengths

- Campobasso, Carlo P, Bugelli, Valentina, Carfora, Anna, Borriello, Renata, Villet, Martin H

Authors: Campobasso, Carlo P , Bugelli, Valentina , Carfora, Anna , Borriello, Renata , Villet, Martin H
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , book chapter
Identifier: http://hdl.handle.net/10962/442717 , vital:74027 , ISBN 9781351163767 , https://www.taylorfrancis.com/chapters/edit/10.4324/9781351163767-13/advances-entomotoxicology-carlo-campobasso-valentina-bugelli-anna-carfora-renata-borriello-martin-villet
Description: Forensic entomotoxicology deals mainly with the analysis of the tissues of insects to identify toxicants present in their food sources. Insects feeding on human tissues can ingest all of the xenobiotic substances taken by living individuals, such as common prescription and illicit drugs. Ecotoxicology is a well-established scientific discipline from which environmental forensic entomotoxicology is derived as a relatively new branch. Entomotoxicology also addresses the effects of drugs and toxins on arthropod development, survival, morphology, and their implications for estimating postmortem intervals. The primary focus of a forensic toxicologist is the detection of toxicants from human tissue samples to help in determining the cause of death. Like nutrients, toxicants encountered by an insect may be assimilated, digested, absorbed, and either sequestered, metabolized, or excreted. Entomological samples are currently of limited quantitative value in forensic toxicology.
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Date Issued: 2019

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An analysis of the fruit-sucking and fruit-piercing moth complex in citrus orchards in South Africa

- Goddard, Mathew K, Hill, Martin P, Moore, Sean D

Authors: Goddard, Mathew K , Hill, Martin P , Moore, Sean D
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/407000 , vital:70329 , xlink:href="https://hdl.handle.net/10520/EJC-15072d6de5"
Description: Fruit-piercing moths are a sporadic pest of citrus, especially in the Eastern Cape Province of South Africa, where the adults can cause significant damage in outbreak years. However, growers confuse fruit-piercing moths with fruit-sucking moths that do not cause primary damage. In this study we trapped these moths during the 2013–2015 growing seasons. A large number of diverse fruit-feeding moths were collected through weekly sampling in citrus orchards in the Eastern Cape and northern Limpopo provinces. Twenty-three species of fruit-feeding moth were trapped. However, only two were fruit-piercing species, capable of causing primary damage, namely Serrodes partita (Fabricius) (Erebidae) and Eudocima divitiosa (Walker) (Erebidae). Surprisingly S. partita, which has been reported as the main fruit-piercing moth pest of citrus in South Africa, comprised only 6.9 % of trap catches. The categorisation of moths as fruit-piercing or fruit-sucking (causing secondary damage) was confirmed by examining the morphological structures (tearing hooks and erectile barbs) of these moths’ proboscides. This study has shown that in non-outbreak seasons, S. partita comprised only a small percentage of fruit-feeding moths in citrus orchards. However, growers may misidentify the harmless fruit-sucking species as fruit-piercing species, and thus overestimate the density of fruit-piercing moths.
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Date Issued: 2019

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An artificial neural network approach to predict the effects of formulation and process variables on prednisone release from a multipartite system

- Manda, Arthur, Walker, Roderick B, Khamanga, Sandile M

Authors: Manda, Arthur , Walker, Roderick B , Khamanga, Sandile M
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/183237 , vital:43933 , xlink:href="https://doi.org/10.3390/pharmaceutics11030109"
Description: The impact of formulation and process variables on the in-vitro release of prednisone from a multiple-unit pellet system was investigated. Box-Behnken Response Surface Methodology (RSM) was used to generate multivariate experiments. The extrusion-spheronization method was used to produce pellets and dissolution studies were performed using United States Pharmacopoeia (USP) Apparatus 2 as described in USP XXIV. Analysis of dissolution test samples was performed using a reversed-phase high-performance liquid chromatography (RP-HPLC) method. Four formulation and process variables viz., microcrystalline cellulose concentration, sodium starch glycolate concentration, spheronization time and extrusion speed were investigated and drug release, aspect ratio and yield were monitored for the trained artificial neural networks (ANN). To achieve accurate prediction, data generated from experimentation were used to train a multi-layer perceptron (MLP) using back propagation (BP) and the Broyden-Fletcher-Goldfarb-Shanno (BFGS) 57 training algorithm until a satisfactory value of root mean square error (RMSE) was observed. The study revealed that the in-vitro release profile of prednisone was significantly impacted by microcrystalline cellulose concentration and sodium starch glycolate concentration. Increasing microcrystalline cellulose concentration retarded dissolution rate whereas increasing sodium starch glycolate concentration improved dissolution rate. Spheronization time and extrusion speed had minimal impact on prednisone release but had a significant impact on extrudate and pellet quality. This work demonstrated that RSM can be successfully used concurrently with ANN for dosage form manufacture to permit the exploration of experimental regions that are omitted when using RSM alone.
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Date Issued: 2019

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An integrated framework for assessing coastal community vulnerability across cultures, oceans and scales

- Aswani, Shankar, Howard, J A, Gasalla, Maria A, Jennings, Sarah, Malherbe, W, Martins, I M, Salim Shyam, Van Putten, Ingrid E, Swathilekshmi, P S, Narayanakumar, R, Watmough G R

Authors: Aswani, Shankar , Howard, J A , Gasalla, Maria A , Jennings, Sarah , Malherbe, W , Martins, I M , Salim Shyam , Van Putten, Ingrid E , Swathilekshmi, P S , Narayanakumar, R , Watmough G R
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/421581 , vital:71863 , xlink:href="https://doi.org/10.1080/17565529.2018.1442795"
Description: Coastal communities are some of the most at-risk populations with respect to climate change impacts. It is therefore important to determine the vulnerability of such communities to co-develop viable adaptation options. Global efforts to address this issue include international scientific projects, such as Global Learning for Local Solutions (GULLS), which focuses on five fast warming regions of the southern hemisphere and aims to provide an understanding of the local scale processes influencing community vulnerability that can then be up-scaled to regional, country and global levels. This paper describes the development of a new social and ecological vulnerability framework which integrates exposure, sensitivity and adaptive capacity with the social livelihoods and food security approaches. It also measures community flexibility to understand better the adaptive capacity of different levels of community organization. The translation of the conceptual framework to an implementable method is described and its application in a number of “hotspot” countries, where ocean waters are warming faster than the rest of the world, is presented. Opportunities for cross-cultural comparisons to uncover similarities and differences in vulnerability and adaptation patterns among the study’s coastal communities, which can provide accelerated learning mechanisms to other coastal regions, are highlighted. The social and ecological framework and the associated survey approach allow for future integration of local-level vulnerability data with ecological and oceanographic models.
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Date Issued: 2019

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An oversimplification of physiological principles leads to flawed macroecological analyses

- Boyles, Justin G, Levesque, Danielle L, Nowack, Julia, Wojciechowski, Michal S, Stawski, Clare, Fuller, Andrea, Smit, Ben, Tattersall, Glenn J

Authors: Boyles, Justin G , Levesque, Danielle L , Nowack, Julia , Wojciechowski, Michal S , Stawski, Clare , Fuller, Andrea , Smit, Ben , Tattersall, Glenn J
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/440505 , vital:73788 , https://doi.org/10.1002/ece3.5721
Description: In light of the rapidly changing climate, there is an urgent need to develop a mechanistic understanding of how physiological functioning mediates ecological patterns. Recently, there has been a spate of papers using analyses that scale up from a standard physiological model, the Scholander–Irving model, to make predictions about range constraints on endothermic vertebrates (Buckley, Khaliq, Swanson, and Hof, 2018; Fristoe et al., 2015; Khaliq, Böhning‐Gaese, Prinzinger, Pfenninger, and Hof, 2017; Khaliq, Hof, Prinzinger, Böhning‐Gaese, and Pfenninger, 2014). Here, we argue that oversimplifications of the Scholander–Irving model and the use of questionable datasets lead to questionable macrophysiological analyses. Many of these problems have been addressed elsewhere, directly and indirectly (eg, McKechnie, Coe, Gerson, and Wolf, 2017; Mitchell et al., 2018), although the focus has largely been on the applicability of the Scholander–Irving model to warm environmental temperatures, which are often seen as more relevant to climate change. However, one specific aspect of the Scholander–Irving model, the assumption that energy expenditure of an endotherm below the thermoneutral zone (TNZ) can be described by basic Newtonian physics, has been used incorrectly in several papers. While not the only paper based on this assumption, the recent work by Buckley et al.(2018) reinvigorated discussions among physiologists about improper interpretations of the Scholander–Irving model. Our concerns are not new and have been voiced repeatedly in the past (Calder and Schmidt‐Nielsen, 1967; King, 1964; Tracy, 1972), but many of these ideas seem to have been buried by time.
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Date Issued: 2019

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Antiplasmodial Activity of the n-Hexane Extract from Pleurotus ostreatus (Jacq. ex. Fr) P. Kumm

- Afieroho, Ozadheoghene E, Siwe-Noundou, Xavier, Onyia, Chiazor P, Festus, Osamuyi H, Chukwu, Elizabeth C, Adedokun, Olutayo M, Isaacs, Michelle, Hoppe, Heinrich C, Krause, Rui W M, Abo, Kio A

Authors: Afieroho, Ozadheoghene E , Siwe-Noundou, Xavier , Onyia, Chiazor P , Festus, Osamuyi H , Chukwu, Elizabeth C , Adedokun, Olutayo M , Isaacs, Michelle , Hoppe, Heinrich C , Krause, Rui W M , Abo, Kio A
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/194981 , vital:45516 , xlink:href="https://doi.org/10.4274/tjps.18894"
Description: Objectives: Several mushrooms species have been reported to be nematophagous and antiprotozoan. This study reported the antiplasmodial and cytotoxic properties of the n-hexane extract from the edible mushroom Pleurotus ostreatus and the isolation of a sterol from the extract. Materials and Methods: Antiplasmodial and cytotoxicity assays were done in vitro using the plasmodium lactate dehydrogenase assay and human HeLa cervical cell lines, respectively. The structure of the isolated compound from the n-hexane extract was elucidated using spectroscopic techniques. Results: The n-hexane extract (yield: 0.93% w/w) showed dose dependent antiplasmodial activity with the trend in parasite inhibition of: chloroquine (IC50=0.016 μg/mL) > n-hexane extract (IC50=25.18 μg/mL). It also showed mild cytotoxicity (IC50>100 μg/mL; selectivity index >4) compared to the reference drug emetine (IC50=0.013 μg/mL). The known sterol, ergostan-5,7,22-trien-3-ol, was isolated and characterized from the extract. Conclusion: This study reporting for the first time the antiplasmodial activity of P. ostreatus revealed its nutraceutical potential in the management of malaria.
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Date Issued: 2019

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Assessing household food insecurity experience in the context of deforestation in Cameroon

- Ngome, Precillia I T, Shackleton, Charlie M, Degrande, Ann, Nossi, Eric J, Ngome, Francis

Authors: Ngome, Precillia I T , Shackleton, Charlie M , Degrande, Ann , Nossi, Eric J , Ngome, Francis
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/398180 , vital:69382 , xlink:href="https://doi.org/10.1016/j.foodpol.2019.02.003"
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Date Issued: 2019

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Assessing the impact of the expanded Global Gag Rule in South Africa

- du Plessis, Ulandi, Sofika, Dumisa, Macleod, Catriona I, Mthethwa, Thobile

Authors: du Plessis, Ulandi , Sofika, Dumisa , Macleod, Catriona I , Mthethwa, Thobile
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , report
Identifier: http://hdl.handle.net/10962/434306 , vital:73047 , ISBN Report , https://www.ru.ac.za/media/rhodesuniversity/content/criticalstudiesinsexualitiesandreproduction/documents/IWHC_Report.pdf
Description: South Africa has one of the most progressive abortion laws in the world and as the constitution states, South Africans also have “the right to make deci-sions concerning reproduction”(Constitution of the Republic of South Africa, 1996). Alongside being a free service, this should seemingly translate into accessible country-wide abortion services. However, less than one in ten public clinics actually perform abortions (Amnesty International, 2017). One of the main reasons for this has been the failure, on the part of the Depart-ment of Health, to regulate conscientious objection, ie the right of a healthcare worker to refuse to provide a service against which they are mor-ally opposed. Another reason is a lack of resources, in terms of both health professionals and finances, which manifest particularly in rural areas. As a result, women who are considering abortion either turn to illegal providers whose advertisements are scattered around towns, or towards private ser-vice providers such as Marie Stopes. Both options are usually costly, espe-cially to poor women. And illegal backstreet abortions often result in sepsis and infection. Recent data on abortion services in South Africa indicate that between 2016 and 2017, 20% of all abortions performed on women aged between 15-44 years were provided by the public health sector, while 26% and 54% of abortions were performed by illegal providers and the private health sector respectively (Lince-Deroche et al., 2018).
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Date Issued: 2019

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Asymmetrical and symmetrical zinc phthalocyanine-cobalt ferrite conjugates embedded in electrospun fibers for dual photocatalytic degradation of azo dyes: Methyl Orange and Orange G

- Mapukata, Sivuyisiwe, Kobayashi, Nagao, Kimura, Mutsumi, Nyokong, Tebello

Authors: Mapukata, Sivuyisiwe , Kobayashi, Nagao , Kimura, Mutsumi , Nyokong, Tebello
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/186960 , vital:44551 , xlink:href="https://doi.org/10.1016/j.jphotochem.2019.04.048"
Description: The conjugation of a symmetrical and an asymmetrical zinc phthalocyanine with amine functionalised cobalt ferrite magnetic nanoparticles (CoFe MNPs) for enhanced photophysics and photocatalysis is reported. The MNPs, 2-[5-(phenoxy)-isophthalic acid] 9(10), 16(17), 23(24)-tris (tertbutyl) phthalocyaninato Zn (II) (2) and 2, 10, 16, 24 – tetra 5-(phenoxy)-isophthalic acid phthalocyaninato] Zn (II) (3) as well as their respective conjugates are embedded into electrospun polyamide-6 (PA-6) fibers for support and catalyst regeneration. The resulting photocatalyts (CoFe/PA-6, 2/PA-6, 3/PA-6, CoFe-2/PA-6, and CoFe-3/PA-6) were compared based on their photophysical properties and photocatalytic efficiencies in degrading azo dyes; Methyl Orange (MO) and Orange G (OG). CoFe-2/PA-6 and CoFe-3/PA-6 were found to be more effective photocatalysts than their respective electrospun Pcs and MNPs. The degradation of OG was found to follow pseudo first order kinetics and the Langmuir–Hinshelwood model while that of MO does not.
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Date Issued: 2019

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Bait collecting by subsistence and recreational fishers in Knysna Estuary may impact management and conservation

- Simon, C, du Toit, A N, Smith, M K S, Claassens, Louw, Smith, F, Smith, P

Authors: Simon, C , du Toit, A N , Smith, M K S , Claassens, Louw , Smith, F , Smith, P
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/447056 , vital:74581 , https://hdl.handle.net/10520/EJC-1d75666653
Description: To facilitate development of tailored management strategies for bait species within Knysna Estuary (South Africa), demand for bait, harvesting activity and perceptions around conservation among recreational and subsistence bait fishers were investigated. In 2015 and 2016, bait collectors were interviewed (n = 84) and observed (n = 167) during low tides at six sites during peak and off-peak holiday periods. Significant associations among subsistence and recreational fishers and their favoured bait species, collecting spots and method, frequency of collection, views on regulations and desired daily limit for mudprawns suggest differences that may warrant different management strategies. Furthermore, observed methods and duration of bait collecting differed according to site, suggesting spatial variation in baiting pressures. Subsistence fishers potentially collect more mudprawns more frequently than do recreational fishers and consequently have a greater impact on mudprawn populations. By contrast, recreational fishers collect more polychaete worms, but because they are mainly active during holidays, their impact on these species may be localised and not yet critical. Most subsistence fishers would like increased daily bag limits, to sell bait and would welcome a rotational zonation scheme to replace the current permanent exclusion zone. The merits and disadvantages of these management options and suggestions are discussed.
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Date Issued: 2019

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Behaviour of an alpine range-restricted species is described by interactions between microsite use and temperature

- Oswald, Krista N, Smit, Ben, Lee, Alan T K, Cunningham, Susan J

Authors: Oswald, Krista N , Smit, Ben , Lee, Alan T K , Cunningham, Susan J
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/441531 , vital:73896 , https://doi.org/10.1016/j.anbehav.2019.09.006
Description: Climate change predictions include increased mean temperatures and increased frequency of heatwaves. Short-term responses to high air temperatures can allow animals to conserve water while maintaining a safe body temperature. For birds, cooling is often through evaporative water loss, which can be physiologically costly. Microsite use is an effective means of conserving water via reducing environmental heat load, so long as there are no negative trade-offs with other necessary functions, such as foraging. We examined behavioural responses to temperature in Cape rockjumpers, Chaetops frenatus (hereafter: ‘rockjumper’), an alpine specialist bird. We hypothesized that rockjumper behaviours would be temperature and microsite dependent. We collected data on rockjumper microsite use (sun, rock shade), behaviour (activity, foraging, preening, panting) and temperature (air, environmental). Rockjumpers made increased use of rock shade as air temperature increased. However, birds in rock shade foraged less. Depending on where their main food source is located, this suggests that when foraging demands are high, birds may need to remain in the sun despite risks of high thermal load, or else may suffer costs of lost foraging opportunities when using shade. The relationship between air temperature and heat dissipation behaviour (panting) was also mediated by microsite: birds showed significant increases in panting with increasing air temperature only when in the sun. The lack of increase in panting for birds in rock shade suggests that shade seeking may buffer physiological thermoregulatory costs (i.e. water expenditure). Individuals may therefore be able to mitigate some potential negative effects of high temperatures by making use of cooler microsites, although this could come at a cost to foraging.
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Date Issued: 2019

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Benchmarking a Decision Support System for Aquatic Toxicity Testing

- Griffin, Neil J, Odume, Oghenekaro N, Mensah, Paul K, Palmer, Carolyn G

Authors: Griffin, Neil J , Odume, Oghenekaro N , Mensah, Paul K , Palmer, Carolyn G
Date: 2019
Subjects: To be catalogued
Language: English
Type: text , report
Identifier: http://hdl.handle.net/10962/437798 , vital:73413 , ISBN 978-0-6392-0108-5 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2445_final1.pdf
Description: This book was written for the catchment management forum (CMF) in the Upper Komati Forum (UKF), and they share their experience in order to help other CMFs understand the damage coal mining does to our water resources. This booklet should be used with How to think and act in ways that make Adaptive IWRM practi-cally possible and How to establish and run a Catchment Management Forum.
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Date Issued: 2019

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