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This study presents multiple sulphur isotope (32S, 33S, 34S, 36S) data on pyrites from silicified volcano‐sedimentary rocks of the Paleoarchean Onverwacht Group of the Barberton greenstone belt, South Africa. These rocks include seafloor cherts and felsic conglomerates that were deposited in shallow marine environments preserving a record of atmospheric and biogeochemical conditions on the early Earth. A strong variation in mass independent sulphur isotope fractionation (MIF‐S) anomalies is found in the cherts, with Δ33S ranging between −0.26‰ and 3.42‰. We explore possible depositional and preservational factors that could explain some of this variation seen in MIF‐S. Evidence for microbial activity is recorded by the c. 3.45 Ga Hooggenoeg Formation Chert (HC4) preserving a contribution of microbial sulphate reduction (−Δ33S and –δ34S), and a c. 3.33 Ga Kromberg Formation Chert (KC5) recording a possible contribution of microbial elemental sulphur disproportionation (+Δ33S and –δ34S). Pyrites from a rhyo‐dacitic conglomerate of the Noisy Formation do not plot along a previously proposed global Felsic Volcanic Array, and this excludes short‐lived pulses of intense felsic volcanic gas emissions as the dominant control on Archean MIF‐S. Rather, we suggest that the MIF‐S signals measured reflect dilution during marine deposition, early diagenetic modification, and mixing with volcanic/hydrothermal S sources. Given the expanded stratigraphic interval (3.47–3.22 Ga) now sampled from across the Barberton Supergroup, we conclude that large MIF‐S exceeding >4‰ is atypical of Paleoarchean near‐surface environments on the Kaapvaal Craton. [ABSTRACT FROM AUTHOR]

Background & objectives: The benefits of long-term adherence to antiretroviral therapy (ART) are countered by interruptions in care or disengagement from care. Healthcare workers (HCWs) play an important role in patient engagement and negative or authoritarian attitudes can drive patients to disengage. However, little is known about HCWs' perspectives on disengagement. We explored HCWs' perspectives on ART disengagement in Khayelitsha, a peri-urban area in South Africa with a high HIV burden. Method: Semi-structured interviews were conducted with 30 HCWs in a primary care HIV clinic to explore their perspectives of patients who disengage from ART. HCWs interviewed included clinical (doctors and nurses) and support staff (counsellors, social workers, data clerks, security guards, and occupational therapists). The interview guide asked HCWs about their experience working with patients who interrupt treatment and return to care. Transcripts were audio-recorded, transcribed, and analysed using an inductive thematic analysis approach. Results: Most participants were knowledgeable about the complexities of disengagement and barriers to sustaining engagement with ART, raising their concerns that disengagement poses a significant public health problem. Participants expressed empathy for patients who interrupted treatment, particularly when the challenges that led to their disengagement were considered reasonable by the HCWs. However, many also expressed feelings of anger and frustration towards these patients, partly because they reported an increase in workload as a result. Some staff, mainly those taking chronic medication themselves, perceived patients who disengage from ART as not taking adequate responsibility for their own health. Conclusion: Lifelong engagement with HIV care is influenced by many factors including disclosure, family support, and HCW interactions. Findings from this study show that HCWs had contradictory feelings towards disengaged patients, experiencing both empathy and anger. Understanding this could contribute to the development of more nuanced interventions to support staff and encourage true person-centred care, to improve patient outcomes. [ABSTRACT FROM AUTHOR]

Introduction: Administering patient-reported outcome measures (PROMs) by text message may improve response rate in hard-to-reach populations. This study explored cultural acceptability of PROMs and compared measurement equivalence of the EQ-5D-3L administered on paper and by text message in a rural South African setting.Materials and Methods: Participants with upper or lower limb orthopaedic pathology were recruited. The EQ-5D was administered first on paper and then by text message after 24 h and 7 days. Differences in mean scores for paper and text message versions of the EQ-5D were evaluated. Test-retest reliability between text message versions was evaluated using Intraclass Correlation Coefficients (ICCs).Results: 147 participants completed a paper EQ-5D. Response rates were 67% at 24 h and 58% at 7 days. There were no differences in means between paper and text message responses for the EQ-5D Index (p = 0.95) or EQ-5D VAS (p = 0.26). There was acceptable agreement between the paper and 24-h text message EQ-5D Index (0.84; 95% Confidence Interval (CI) 0.78-0.89) and EQ-5D VAS (0.73; 95% CI 0.64-0.82) and acceptable agreement between the 24-h and 7-day text message EQ-Index (0.72; CI 0.62-0.82) and EQ-VAS (0.72; CI 0.62-0.82). Non-responder traits were increasing age, Xhosa as first language and lower educational levels.Conclusions: Text messaging is equivalent to paper-based measurement of EQ-5D in this setting and is thus a viable tool for responders. Non-responders had similar socioeconomic characteristics and attrition rates to traditional modes of administration. The EQ-5D by text message offers potential clinical and research uses in hard-to-reach populations. [ABSTRACT FROM AUTHOR]

Livestock losses are often integral to human conflicts over carnivores; these conflicts threaten the livelihoods of many communities, as well as carnivore species survival. To begin assessing livestock depredation and conflict over carnivores in South Africa's Northern Cape Province, a farmers' union meeting was used to capture farmer (n = 22) perceptions of carnivores in 2017. Most farmers reported black-backed jackals and caracals (n = 11 and 10, respectively) as most frequently culpable for livestock losses. However, culpability and reported presence on farmlands by these and other carnivore species were not always aligned. Carnivores were generally perceived in a negative manner, with most respondents supporting livestock protection methods involving the removal or separation of carnivores from farmland, as opposed to those facilitating coexistence. Comprehensive socio-ecological investigation of factors relevant to improving humancarnivore coexistence of benefit to both farmers and wildlife is warranted in this region. [ABSTRACT FROM AUTHOR]

Despite the difficulties experienced by asylum-seekers in South Africa, little research has explored long-term asylum applicants. This exploratory qualitative study describes how protracted asylum procedures and associated conditions are experienced by Congolese asylum - seekers in Tshwane, South Africa. Eighteen asylum-seekers and eight key informants participated in the study. All asylum-seekers had arrived in South Africa between 2003 and 2013, applied for asylum within a year of arrival in Tshwane, and were still in the asylum procedure at the time of the interview, with an average of 9 years since their application. Thematic analysis was used to analyse the data. The findings presented focus on the process of leaving the Democratic Republic of Congo, applying for asylum and aspirations of positive outcomes for one's life. Subsequently, it describes the reality of prolonged periods of unfulfilled expectations and how protracted asylum procedures contribute to poor mental health. Furthermore, coping mechanisms to mitigate these negative effects are described. The findings suggest that protracted asylum procedures in South Africa cause undue psychological distress. Thus, there is both a need for adapted provision of mental health services to support asylum-seekers on arrival and during the asylum process, and systemic remediation of the implementation of asylum procedures. [ABSTRACT FROM AUTHOR]

Background: Treatment success rates for multidrug-resistant tuberculosis (MDR-TB) in South Africa remain close to 50%. Lack of access to timely, decentralized care is a contributing factor. We evaluated MDR-TB treatment outcomes from a clinical cohort with task-sharing between a clinical nurse practitioner (CNP) and a medical officer (MO). Methods: We completed a retrospective evaluation of outcomes from a prospective, programmatically-based MDR-TB cohort who were enrolled and received care between 2012 and 2015 at a peri-urban hospital in KwaZulu-Natal, South Africa. Treatment was provided by either by a CNP or MO. Findings: The cohort included 197 participants with a median age of 33 years, 51% female, and 74% co-infected with HIV. The CNP initiated 123 participants on treatment. Overall MDR-TB treatment success rate in this cohort was 57.9%, significantly higher than the South African national average of 45% in 2012 (p<0·0001) and similar to the provincal average of 60% (p = NS). There were no significant differences by provider type: treatment success was 61% for patients initiated by the CNP and 52.7% for those initiated by the MO. Interpretation: Clinics that adopted a task sharing approach for MDR-TB demonstrated greater treatment success rates than the national average. Task-sharing between the CNP and MO did not adversely impact treatment outcome with similar success rates noted. Task-sharing is a feasible option for South Africa to support decentralization without compromising patient outcomes. Models that allow sharing of responsibility for MDR-TB may optimize the use of human resources and improve access to care. [ABSTRACT FROM AUTHOR]

The authors present a response on a commentary by C. R. McClung et al on their article about the origin of the Bushmanland ore district in South Africa. They anticipate that the problem with established rules of stratigraphic nomenclature will be addressed by the South African Committee for Stratigraphy. They note the effort of McClung et al in attempting to discredit the relevance of their ore horizon samples. They also mention oppressive remarks on their work on Hoogoor Gneiss sample DC03104.

Presents a study that examined the ranging behavior of Addo elephants in the Addo Elephant National Park in South Africa. Methods used to determine whether natural patterns of male and female ranging behavior of the elephants can be maintained within a confined area; Observations on the ranging patterns of the females when in musth; Suggestions regarding the frequency of contact between musth and non-musth male elephants.

Presents a study that investigated the existence of paternity in the elephant population of the Addo Elephant National Park in South Africa from 1982-1996. Methodology; Results; Discussion.

Abstract Widespread hunting had fragmented and severely reduced elephant populations in South Africa by 1900. Elephant numbers increased during the 1900s, although rates of recovery of individual populations varied. The Kruger National Park elephant population increased rapidly, to more than 6000 by 1967, with recruitment boosted by immigration from Mozambique. The Addo Elephant National Park population was reduced to 11 elephants in 1931 and remains relatively small (n = 325). Loss of genetic variation is expected to occur whenever a population goes through a bottleneck, especially when post-bottleneck recovery is slow. Variation at nine polymorphic microsatellite loci was analysed for Kruger and Addo elephants, as well as museum specimens of Addo elephants shot prior to the population bottleneck. Significantly reduced genetic variation and heterozygosity were observed in Addo in comparison to Kruger (mean alleles/locus and H E: Addo 1.89, 0.18; Kruger 3.89, 0.44). Two alleles not present in the current Addo population were observed in the museum specimens. Addo elephants represent a genetic subset of the Kruger population, with high levels of genetic differentiation resulting from rapid genetic drift. The Kruger population is low in genetic diversity in comparison to East African elephants, confirming this population also suffered an appreciable bottleneck. [ABSTRACT FROM AUTHOR]

Traces the history of the Addo elephant population in South Africa. Background of Addo Elephant National Park (AENP); Estimation of dates of birth and death of each individual elephants; Preliminary demographic analyses for the period 1976-1998.

• Pb isotopes indicate sulphide mineralization age and contribution of evolved (crustal) material. • MIF-S require recycling of pre 2.43 Ga atmospheric sulphur into carbonatite-phoscorite melts. • Mantle plume melts assimilated subduction-metasomatized subcontinental lithospheric mantle. Lead and multiple sulphur isotope compositions were measured in-situ by SIMS on sulphide minerals from phoscorites and carbonatites of the ca. 2.06 Ga Phalaborwa Complex in South Africa. Additionally, sulphide mineral separates and bulk-rock samples were analyzed with IRMS methods to confirm SIMS data. Lead isotope ratios define a trend stretching from unradiogenic to highly radiogenic ratios corresponding to a Pb–Pb regression date of 2054 ± 99 Ma. This apparent date is consistent with the timing of emplacement and thus provides an age estimate for the sulphide mineralization. The least radiogenic Pb isotope compositions overlap, and the regression line intersects, a hypothetical mixing line between MORB mantle and an upper crustal reservoir at ca. 2.1 Ga, suggesting that either a significant quantity of crustal Pb contributed to sulphide mineralization, or that sulphidic xenomelts were derived from an isotopically enriched mantle source. Sulphur isotope ratios of individual sulphide minerals obtained by SIMS are highly variable (δ 34 S: −15 to +15‰ V-CDT) and, importantly, reveal the contribution of pre-Great Oxidation Event (GOE) atmospheric sulphur with mass-independent isotope fractionation (Δ 33 S = δ 33 S–[(1 + δ 34 S)0.515-1]×1000 ≠0.0‰). Mass-independent sulphur isotope fractionation is also revealed by sulphur isotope ratios measured on sulphide mineral separates (Δ 33 S: 0.2 to 0.7‰) and bulk rock samples (Δ 33 S: 0.2 to 0.4‰). Generally, the range of sulphur isotope ratios obtained with SIMS is much larger than that observed in non-SIMS data, possibly reflecting isotopic variability at the μm scale, resolvable only with microbeam measurements. Various sources and mechanisms by which supracrustal material may have been incorporated into mantle-derived carbonatite-phoscorite magmas are assessed, taking into account that geological evidence for the presence of sedimentary material available for assimilation during shallow-level magma emplacement is lacking. Given the variability in S and Pb isotopic compositions, it is inferred that pre-GOE surficial Pb and S were not derived from asthenospheric mantle contaminated with supracrustal materials. Instead, whole rock trace element compositions, in concert with published geochemical and petrological evidence, are consistent with interaction of asthenospheric, plume-derived melt with compositionally heterogeneous lithospheric mantle that was metasomatically modified by fluids and melts released from a subducting slab. Despite geochemical and geochronological similarities with the 2055 Ma Busvheld Complex, lead and sulphur isotope data for both complexes are resolvably different, pointing to distinct lithospheric mantle sources involved in sulphide mineralization. [ABSTRACT FROM AUTHOR]

Livestock guardian dogs are one of several predator control methods employed by livestock farmers around the world, but little is known about the factors that predict their use. Here we aim to understand the dimensions which influence guardian dog use by farmers. In a quantitative survey among 113 livestock farmers in South Africa, using Boosted Regression Trees, we explored and characterized the factors associated with guardian dog use. We showed that practical factors (e.g., predator type, number of farming enterprises, mitigation methods, and the frequency and extent of specific predator problems) were more likely to be significant determinants of guardian dog use than sociodemographic factors. However, psychosocial constructs relating to wildlife value orientations, empathy for predators, tolerance to predators, tangible and intangible cost, benefits of predators, like or dislike of predators, and number of positive experiences, were also determinants of guardian dog use. Utilizing the foundational constructs of the Theory of Planned Behavior (TPB) and Wildlife Tolerance Model (WTM) we built upon these findings to show that constructs of attitude, subjective norms, and perceived behavioral control explained 49 % of the variance in behavioral intention to use or continue using a guardian dog. The relationship between attitude and the behavioral intent to use or continue using a guardian dog had less significant association with guardian dog use than either perceived behavioral control or subjective norms had. Nonetheless, attitude was most strongly associated with the constructs of belief in a specific non-governmental organization, mutualistic Wildlife Value Orientations and perceptions of affordability, ease of use and the effectiveness of guardian dogs. The TPB model, incorporating elements of the WTM, provides a framework to guide and improve adoption of guardian dog programs or other intervention strategies within conservation contexts. [ABSTRACT FROM AUTHOR]

The article focuses on the need for healthcare professionals in South Africa to check the terms and conditions of insurance agreements and to ensure that they practise within the boundaries of their insurance. According to the authors, less financially stable providers are withdrawing from the medical malpractice market, particularly obstetricians and neurosurgeons

Abstract Evaluation of alternative techniques used to estimate elephant population sizes is important in order to assess the accuracy of the results obtained, upon which management decisions may be based. Data from annual helicopter surveys carried out in the Addo Elephant National Park (1978–97) are compared with registration counts obtained from intensive ground surveys in which all elephants within the park are individually known. On average, total population size estimated in aerial surveys is 8.0% lower than registration counts (n 1997 = 251), aerial calf (< 1 year) counts are 48.8% lower than registration counts, and aerial carcass counts are 50% below the total number of deaths documented in ground surveys. Registration counts provide more accurate demographic data than aerial surveys, the results of which are shown to vary widely and unpredictably, thus compromising their value. Where population estimates rely exclusively on aerial surveys, replicate counts are recommended in order to generate confidence intervals. [ABSTRACT FROM AUTHOR]

Geochemical and isotopic fluid signatures from a 2.9–3.2 km deep, 45–55 °C temperature, hypersaline brine from Moab Khotsong gold and uranium mine in the Witwatersrand Basin of South Africa were combined with radiolytic and water–rock isotopic exchange models to delineate brine evolution over geologic time, and to explore brine conditions for habitability. The Moab Khotsong brines were hypersaline (Ca-Na-Cl) with 215–246 g/L TDS, and Cl− concentrations up to 4 mol/L suggesting their position as a hypersaline end-member significantly more saline than any previously sampled Witwatersrand Basin fluids. The brines revealed low DIC (∼0.266–∼1.07 mmol/L) with high (∼8.49–∼23.6 mmol/L) DOC pools, and several reduced gaseous species (up to 46 % by volume H 2) despite microoxic conditions (Eh = 135–161 mV). Alpha particle radiolysis of water to H 2 , H 2 O 2 , and O 2 along with anhydrous-silicate-to-clay alteration reactions predicted 4 mol/L Cl− brine concentration and deuterium enrichment in the fracture waters over a period > 1.00 Ga, consistent with previously reported 40Ar noble gas-derived residence times of 1.20 Ga for this system. In addition, radiolytic production of 7–26 nmol/(L × yr) H 2 , 3–11 nmol/(L × yr) O 2 , and 1–8 nmol/(L × yr) H 2 O 2 was predicted for 1–100 μ g/g 238U dosage scenarios, supporting radiolysis as a significant source of H 2 and oxidant species to deep brines over time that are available to a low biomass system (102–103 cells/mL). The host rock lithology was predominately Archaean quartzite, with minerals exposed on fracture surfaces that included calcite, pyrite, and chlorite. Signatures of δ 18O calcite , δ 13C calcite , Δ33S pyrite, δ 34S pyrite and 87Sr/86Sr obtained from secondary ion mass spectrometry (SIMS) microanalyses suggest several discrete fluid events as the basin cooled from peak greenschist conditions to equilibrium with present-day brine temperatures. The brine physiochemistry, geochemistry, and cellular abundances were significantly different from those of a younger, shallower, low salinity dolomitic fluid in the same mine, and both were different from the mine service water. These results indicate the discovery of one of few long-isolated systems that supports subsurface brine formation via extended water–rock interaction, and an example of a subsurface brine system where abiotic geochemistry may support a low biomass microbial community. [ABSTRACT FROM AUTHOR]

Granular neoblastic zircon (ZrSiO 4) with systematically oriented granules has been proposed as evidence for extreme shock pressures (>30 GPa) and subsequent high temperatures (>1200 °C). It is widely agreed to reflect the solid-state phase transition from zircon to its high-pressure polymorph reidite and subsequent reversion to zircon. This model is based on crystallographic relationships between granules of a single type of granular zircon and does not explain the formation of other types of granular zircon textures, for example, grains with randomly oriented granules or with large, often euhedral granules. Here we report the first nano-scale observations of granular neoblastic zircon and the surrounding environment. We conducted combined microstructural analyses of zircon in the lithic clast from an impact melt dike of the Vredefort impact structure. Zircon granules have either random or systematic orientation with three mutually orthogonal directions of their c -axes coincident with [110] axes. Each 1-2 μm zircon granule is a mosaic crystal composed of nanocrystalline subunits. Granules contain round inclusions of baddeleyite (monoclinic ZrO 2) and amorphous silica melt. Tetragonal and cubic ZrO 2 also occur as sub-μm-sized inclusions (<50 nm). Filament-like aggregates of nanocrystalline zircon are present as "floating" in the surrounding silicate matrix. They are aligned with each other, apparently serving as the building blocks for the mosaic zircon crystals (granules). Our results indicate shock-related complete melting of zircon with the formation of immiscible silicate and oxide melts. The melts reacted and crystallized rapidly as zircon granules, some of which experienced growth alignment/twinning and parallel growth, causing the characteristic systematic orientation of the granules observed for some of the aggregates. In contrast to the existing model, in which this type of granular zircon is considered to be a product of reversion from the high-pressure polymorph reidite, our nano-scale observations suggest a formation mechanism that does not require phase transition via reidite but is indicative of instant incongruent decomposition, melting and rapid crystallization from the melt. • Granular neoblastic zircon is found in a small clast in Vredefort impact melt. • Zircon granules with systematic or random orientations retain the age of impact. • Nano-structural study shows inclusions of Zr oxide and silicate glass in zircon. • Each zircon granule is a mosaic crystal composed of nano-sized crystals. • Nano-scale features point at crystallization from two immiscible melts. [ABSTRACT FROM AUTHOR]