A decision-making framework for restoring riparian zones degraded by invasive alien plants in South Africa

Riparian habitats in many parts of South Africa are severely degraded by invasive alien plants, especially trees. These invasions reduce water yields from catchments and affect riverine functioning and biodiversity. Initiatives are under way countrywide to clear alien plants from watercourses and surrounding catchments. Current understanding of key processes that regulate riparian functioning and define options for restoration is rudimentary. We review the impacts of riparian invasions and identify factors limiting the recovery of natural vegetation following alien clearance. We propose a framework of strategic interventions for optimizing restoration success. The framework identifies abiotic and biotic barriers to restoration at the scales of catchments and local reaches. In highly transformed catchments, interventions at the reach scale may fail if important barriers at the catchment scale are not addressed. The extent to which propagule supply and microsite conditions inhibit vegetation recovery is unknown. We also know little of the relative importance of dispersing vegetative propagules, dispersing seeds and soil-stored seed banks in vegetation dynamics, particularly after severe disturbances such as dense invasion by alien plants. The importance of geomorphological and hydrological factors in mediating recovery of riparian vegetation has not been adequately explored for all climatic areas in South Africa. More research is needed to determine the influence of different alien species and clearing treatments on the recovery of riparian vegetation. The literature strongly suggests that in highly alien-transformed catchments, the re-introduction of riparian species is required to promote recovery and suppress re-invasion. However, such interventions are unlikely to be widely implemented unless the cost: benefit ratios are favourable

Some key topographic and material controls on debris flows in Scotland

Debris-flow phenomena were investigated at six study sites across upland Scotland using a combination of laboratory and field-based analyses. In agreement with previous research, higher spatial frequencies of debris-flow paths were measured in areas underlain by coarse-grained intrusive igneous and arenaceous sedimentary bedrocks compared with metamorphic and extrusive igneous geologies. A strong relationship between critical state friction angle of sampled initiation zone soils and spatial frequency of debris-flow paths suggests that this trend is attributable to generally lower shear strengths in sandier hillslope material generated from coarser grained bedrocks. Topographic controls on debris-flow susceptibility are demonstrated by higher numbers of debris-flow paths at sites with persistently steep upper slopes (=30°) and a higher occurrence of potential initiation zones. Strong correlation between debris-flow magnitude and slope length shows that longer mass movements tend to produce higher volumes of material and terminal deposits that travel further at the slope foot. In the cases studied here this reflects greater opportunity for accumulation of fresh material during the transport phase, particularly in the case of long channelized flows. The highest levels of hazard are likely to occur where these topographic and material characteristics conducive to heightened susceptibility and magnitude coincide.</p

Trustworthiness of South African sustainability reports : an overview

Published ArticleIt is widely assumed that sustainability reporting is a mechanism that companies can use to demonstrate their trustworthiness with regard to development in a sustainable manner. This article uses the Mayer, Davis and Schoorman trust model as basis to discuss how sustainability reporting can enhance trustworthiness in a sustainable development context. The study also uses a survey-questionnaire, sent to South African sustainability reporters, to explore whether they are finding sustainability reporting useful for enhancing companies' trustworthiness among stakeholders in a sustainable development context. Respondents indicate, amongst other things, that sustainability reporting in South Africa has a role to play in enhancing trustworthiness, more so among contractual stakeholders than among community stakeholders. To entrench trust benefits in the long term will however require long term strategies. Such strategies should focus on increasing the engagement of community stakeholders, authentic use of the GRI and implementing effective control systems that prevent the misuse of sustainability reports, while not preventing the formation of real trust

Mental Toughness in South African Youth: Relationships With Forgivingness and Attitudes Towards Risk

Young people are particularly vulnerable to health risk behaviors and interpersonal violence, stimulating scholars’ attention towards identifying factors that may reduce the likelihood that these actions will occur. Associated with positive outcomes in a variety of domains, mental toughness in young people might protect them from engaging in potentially deleterious interpersonal or health-risk behaviors, while potentially promoting positive psychological behaviors. Within this framework, the present study investigated the relationships between mental toughness, attitudes towards physical and psychological risk-taking, and trait forgiveness in a sample of 123 (males = 54, females = 69) South African youth (M age = 23.97 years, SD = 4.46). Univariate and multivariate analyses indicated higher levels of mental toughness were associated with being more forgiving, (η2pηp2 = .036), perceiving physical risk-taking more positively (η2pηp2 = .062), but having more negative attitudes towards psychological risk-taking (η2pηp2 = .036). These findings give credence to mental toughness as a psychological characteristic involved in youth risk-taking perceptions and interpersonal functioning. Future research might explore the integration of mental toughness into the development of future youth risk behavior interventions

Post-colonoscopy colorectal cancers in privately insured patients in South Africa

Background. Post-colonoscopy colorectal cancers (PCCRCs) are colorectal cancers (CRCs) that are diagnosed within 3 - 5 years of a colonoscopy where a cancer was not detected. Colonoscopy is the current gold standard for the diagnosis of colorectal cancer. The rate of PCCRC is an indicator of the quality of colonoscopy, because the aim of a high-quality colonoscopy is to detect CRCs and advanced adenomas. Objective. To calculate the rate of PCCRC in a privately insured population in South Africa (SA).Methods. Data were retrospectively obtained from the largest private health insurance company in SA. Patients diagnosed with CRC from the period of 1 January 2013 to 31 December 2019 were included. Patients who were members of the fund for &lt;5 years prior to diagnosis were excluded. Patients with conditions predisposing to CRC were excluded from the study. Patients with CRC who had undergone colonoscopy 6 - 60 months prior to the diagnosis of CRC were defined as PCCRC. Patients diagnosed with CRC were identified by ICD-10 codes and from the oncology registry. Colonoscopies were identified by procedure codes. Results. A diagnosis of CRC was made in 19 538 patients in the 7-year period. Following exclusions, 4 765 patients were included in this study for analysis. PCCRC was identified in 415 patients (8.72%) between 6 and 60 months, of whom 315 were identified between 6 and 36 months (6.61%). The median (interquartile range (IQR)) age in the overall study group presenting with CRC was 64 (53 - 73) years, with that of the PCCRC group (n=415) being higher at a median (IQR) age of 67(53 - 72) years when compared with the non-PCCRC group (n=4 350) of 64 (53 - 72) years (p=0.0002). Overall, 21.3% of CRC patients were aged ≤50 years, and 51.3% were male. The percentages of patients aged ≤50 years in the PCCRC v. non-PCCRC groups were 17.1% (n=71/415) and 21.7% (n=945/4 350), respectively (p=0.03). The gender ratio did not differ in the PCCRC group v. the non-PCCRC group. Rectal cancers were more likely to be present in the PCCRC group at 32.8% (n=136/415) v. the non-PCCRC group at 24% (n=1 043/4 350) (p&lt;0.001). In the PCCRC subset, 73.8% of colonoscopies were performed by surgeons, 13.4% by gastroenterologists and 12.8% by physicians and general practioners/others. The PCCRC rate was 14.4% for gastroenterologists and 7.9% for surgeons. Conclusion. This study is the first study from SA to analyse PCCRC. The overall PCCRC rate was 6.61%, in line with published series

Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.Comment: Published in ApJ (2018 April 5); 13 pages, 4 figure

Living with Inflammatory Bowel Disease: A review of qualitative research studies

© 2018 Elsevier Ltd Background: Inflammatory Bowel Disease is a chronic, untreatable condition represented by two illnesses, Crohn's and Ulcerative Colitis. Despite high incidence in well-developed industrialised countries, and the significant impact of symptoms on patient's quality of life, little is known about living with Inflammatory Bowel Disease. Aim: To explore the patients’ experiences of living with Inflammatory Bowel Disease. Design: A qualitative systematic review. Data sources: CINAHL, Medline, British Nursing Index and PsycINFO were searched using the following keywords: Inflammatory Bowel Disease AND experiences. We have limited the search to studies published in English from 2000 to 2017. Review method: Thematic synthesis. Results: Data from 23 studies, identified that fatigue, incontinence and uncertainty about future, body image, and lack of information from healthcare professionals dominated the experiences of those living with Inflammatory Bowel Disease. Also, patients living with Inflammatory Bowel Disease were reluctant to disclose their illness due to lack of public awareness and stigma surrounding symptoms. From these, an overarching theme has been identified: Living in isolation and exclusion. Conclusion: Patients with Inflammatory Bowel Disease face a variety of problems, often their priorities and those of healthcare professionals differ greatly. Healthcare professionals have little evidence needed to provide adequate, holistic care to this group. With a rise in the Inflammatory Bowel Disease population in newly industrialised countries it is estimated that the condition is turning into a global disease, potentially making long term care unsustainable. More evidence is needed to understand the concerns of this group

Improvement of common bacterial blight resistance in South African dry bean cultiver teebud

Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli is an important seed-borne disease of dry beans in South Africa.&nbsp; Development of resistant cultivars is considered the best control measurement for the disease. Backcross breeding was used to improve&nbsp; BB resistance in the small white canning bean, cv. Teebus, using resistance sources XAN 159 and Wilk 2. High resistance levels in near-isogenic lines, developed in two independent breeding programmes, indicated successful&nbsp; transfer of resistance from both sources. Presence of SCAR-markers, SU91 and BC420, in 35 of 39 XAN 159 derived Teebus lines and all lines derived from Wilk 2, confirmed successful resistance transfer. AFLP studies conducted to determine genetic relatedness of two near-isogenic Teebus lines, showed a similarity of 96.2% with the maximum similarity between&nbsp; these lines and Teebus being 93.1%. One cultivar, Teebus-RCR2 with yield similar to Teebus and improved resistance to CBB has been released from the programme