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Current state of practice for the assessment of liquefied strengths of tailings relies primarily on empirical or semi-empirical correlations based on penetration testing. That is, despite liquefied strength being arguably the most important strength parameter for the design of brittle tailings storage facilities, there is much less success or acceptance of the use of laboratory element tests to support strength selection compared to other forms of strengths inferred in geotechnical engineering. This is particularly the case for tailings at a state near or slightly dense of the critical state line (CSL) for which there is ample evidence of field-scale flow liquefaction but where laboratory element tests often behave in a manner inconsistent with such field-scale response – at least at large strains. The current paper examines the quasi steady state (QSS) strength of sands and tailings for which the CSL has been measured, linking the observed strengths to inferred in situ behaviour through the state parameter. Particular focus is placed on QSS strengths obtained from simple shear tests carried out within a hollow cylinder torsional shear system where the stress state in the test is a better representation of in situ below-slope conditions that the triaxial compression test. In particular, the marked effect of intermediate principal stress on the QSS in sands is highlighted. Alternatively, the negligible anisotropy seen in a sandy silt gold tailings, and the potential implications in the context of QSS strengths and field-scale behaviour, are examined and emphasised.

The purpose of this study was to monitor and compare the growth and productivity of maize/beans sole and inter-cropping systems under conventional (CON) and in-field rainwater harvesting (IRWH) tillage practices. During the typical drought conditions of the 2018/19 growing season, seven homestead gardens of smallholder farmers (four in Paradys and three in Morago villages) in the Thaba Nchu rural communities of South Africa were selected for on-farm demonstration trials. Two tillage systems CON and IRWH as the main plot and three cropping systems as sub-treatment (sole maize and beans and intercropping) were used to measure crop growth and productivity parameters. The results showed that IRWH tillage had significantly higher above-ground dry matter for both sole maize (29%) and intercropped maize (27%) compared to CON treatments. The grain yield under both tillage systems showed that IRWH-Sole >> IRWH-Ic >> CON-Sole >> CON-Ic, with values ranging from 878.2 kg ha−1 to 618 kg ha−1 (p ≤ 0.05). The low harvest index values (0.21–0.38) could have been due to the effect of the drought during the growing season. The results of precipitation use efficiency (PUE) showed that the IRWH tillage was more effective at converting rainwater into maize biomass and grain yield compared to CON tillage. However, the different cropping systems did not show a consistent trend in PUE. During the growing season, the PUE for AGDM varied for different tillage and cropping system treatments in Morago and Paradys. For maize, it ranged between 10.01–6.07 and 9.93–7.67 kg ha−1, while for beans, it ranged between 7.36–3.95 and 7.07–3.89 kg ha−1 mm−1. The PUE for grain yield showed similar trends with the significantly highest values of PUE under IRWH tillage systems for the Morago sites, but there were no significant differences at the Paradys site in both tillage and cropping systems. There is a critical need, therefore, to devise alternative techniques to promote an increase in smallholders’ productivity based on an improved ability to capture and use resources more efficiently.

The purpose of this study was to evaluate alternative management practices such as in-field rainwater harvesting (IRWH) and intercropping techniques through conducting on-farm demonstrations. Seven homestead gardens in Thaba Nchu rural communities in the central part of South Africa were selected as demonstration trials. Two tillage systems, conventional (CON) and IRWH, as the main plot, and three cropping systems as sub-plot (sole maize and beans and intercropping) were used to measure water use and radiation use parameters. The water productivity (WP) of various treatments was positively related to the radiation use efficiency (RUE), and the degree of associations varied for different tillage systems. The water use in IRWH was higher by 15.1%, 8.3%, and 10.1% over the CON for sole maize and beans and intercropping, respectively. Similarly, the intercropping system showed water use advantages over the solely growing crops by 5% and 8% for maize and by 16% and 12% for beans under IRWH and CON tillage, respectively. Maximum RUE was found for sole maize and beans under IRWH, higher by 13% and 55% compared to the CON tillage, respectively. The RUE under IRWH tillage was estimated to be 0.65 and 0.39 g DM MJ−1 in sole maize and intercropping, respectively. However, in sole and intercropped beans, the RUE showed higher values of 1.02 g DM MJ−1 and 0.73 g DM MJ−1, respectively. WP and RUE were associated with water deficits and proportional to lower radiation use. This relationship indicates that the intercepted radiation by plants for photosynthesis is directly related to the transpiration rate until radiation saturation occurs. Therefore, the higher water deficit and lesser efficiency in using the radiation available during the season can be improved by practicing IRWH techniques. Furthermore, in semi-arid areas, to enhance the efficiency of water and radiation usage in intercropping management, it is crucial to adjust plant population and sowing dates based on water availability and the onset of rainfall.

For a soil that is contractive and strain softening at fully saturated conditions the question remains on which degree of saturation can trigger a strain softening response. A common engineering practice is to adopt a saturation threshold (e.g., 85%) and then assume a fully saturated response when saturation is above that value. This study aims to understand how the strain softening response change when tailings are not fully saturated and to propose a systematic method for determining the saturation threshold. A restraint when preparing unsaturated loose samples is that it is likely to have collapse during flashing, thus changing void ratio and making comparisons between different degrees of saturation problematic. A simple procedure to obtain loose samples at different degrees of saturation but at similar post-flushing void ratios is explained and preliminary results of undrained shear strength obtained for gold tailings in triaxial device are presented and discussed.

Laboratory-controlled cone penetration test results of a silty gold tailings in a variety of saturated and unsaturated states, obtained using two calibration chambers, are presented then interpreted using a state parameter-based approach. The research was conducted as part of the TAILLIQ project (tailliq.com), funded by the Australian Research Council and six mining companies, and involving four Australian universities.Cone penetration resistances, which increase due to the presence of suction when the tailings are unsaturated, can be normalised using the initial mean effective stress to establish a relationship with the initial state parameter. The relationship is applicable to saturated and unsaturated conditions, as long as the presence of suction hardening as well as the influence of suction on the mean effective stress are accounted for, and as long as the cone penetrations occur under pseudo drained conditions. The relationships enable state parameters and void ratios to be back-calculated from normalised cone penetration resistances.

BackgroundHousehold contact investigations are effective for finding tuberculosis (TB) cases but are hindered by low referral uptake for clinic-based evaluation and testing. We assessed the acceptability and feasibility of in-home testing of household contacts (HHC) using the GeneXpert Edge platform.MethodsWe conducted a 2-arm, randomized study in Eastern Cape, South Africa. HHCs were verbally assessed using the World Health Organization-recommended 4-symptom screen. Households with ≥1 eligible symptomatic contact were randomized. Intervention households received in-home GeneXpert MTB/RIF molecular testing. GeneXpert-positive HHCs were referred for clinic-based treatment. Standard-of-care households were referred for clinic-based sputum collection and testing. We defined acceptability as agreeing to in-home testing and feasibility as generation of valid Xpert MTB/RIF results. The proportion and timeliness of test results received was compared between groups.ResultsEighty-four households were randomized (n = 42 per arm). Of 100 eligible HHCs identified, 98/100 (98%) provided consent. Of 51 HHCs allocated to the intervention arm, all accepted in-home testing; of those, 24/51 (47%) were sputum productive and 23/24 (96%) received their test results. Of 47 HCCs allocated to standard-of-care, 7 (15%) presented for clinic-based TB evaluation, 6/47 (13%) were tested, and 4/6 (67%) returned for their results. The median (interquartile range) number of days from screening to receiving test results was 0 (0) and 16.5 (11-15) in the intervention and standard-of-care arms, respectively.ConclusionsIn-home testing for TB was acceptable, feasible, and increased HHCs with a molecular test result. In-home testing mitigates a major limitation of household contact investigations (dependency on clinic-based referral), revealing new strategies for enhancing early case detection.

Clofazimine is recommended for the treatment of rifampicin-resistant tuberculosis (RR-TB), but there is currently no verified dosing guideline for its use in children. There is only limited safety and no pharmacokinetic (PK) data available for children. We aimed to characterize clofazimine PK and its relationship with QT-interval prolongation in children. An observational cohort study of South African children

Abstract Background Although HIV vertical transmission has declined significantly in sub-Saharan Africa, incident HIV infection in pregnant and postpartum women is estimated to account for over one-third of HIV vertical transmission. Oral pre-exposure prophylaxis (PrEP) for pregnant and breastfeeding women (PBFW) is included in South African PrEP guidelines since 2021; however, integration of PrEP services within ante- and postnatal care remains limited. Methods Between March 2022 and September 2023, we evaluated the integration of PrEP for PBFW in eight antenatal clinics in Cape Town, South Africa, following training and mentorship of providers. We applied an adapted Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework to evaluate the integration of PrEP services for pregnant and breastfeeding women. Before the study, PrEP was not routinely offered. We implemented a staff didactic/practice-based training and mentorship on PrEP provision targeting PBFW. We evaluated the following: (1) Reach as the proportion of women initiating PrEP among women counselled and tested for HIV, (2) effectiveness as PrEP continuation up to 3 months by pregnant vs. breastfeeding women, (3) adoption of PrEP integration via pre- and post-training assessments and ongoing mentorship assessments, (4) implementation through clinic trends of PrEP offer over time, and (5) maintenance: continued PrEP offer 3 months following the intervention. Results In 8 facilities providing ante- and postnatal care, we trained 224 healthcare providers (127 nurses and 37 counsellors). Of those, we mentored 60 nurses, midwives, and HIV counsellors working with pregnant and breastfeeding women, with 80% of nurse/midwives and 65% of counsellors scoring ≥ 80% on the final mentoring assessment. Overall, 12% of HIV-negative pregnant women started PrEP, and 41% of those continued PrEP up to 3 months. Among HIV-negative breastfeeding women, 14% initiated PrEP, and 25% continued PrEP up to 3 months. All eight facilities continued providing PrEP 3 months post intervention. Conclusions In these high HIV prevalence clinics, the proportion of pregnant and breastfeeding women initiating and continuing PrEP rapidly increased but was limited among breastfeeding women. Staff training, mentorship, and PrEP integration were well-adopted by nurses and counsellors, and services continued following the intervention. Barriers included limited HIV testing of breastfeeding mothers and need for additional PrEP-trained nurses.

Abstract Objectives We have previously reported using gene-deficient mice that the interleukin (IL)-23p19 subunit is required for the development of innate immune-driven arthritic pain and disease. We aimed to explore here, using a number of in vivo approaches, how the IL-23p19 subunit can mechanistically control arthritic pain and disease in a T- and B- lymphocyte-independent manner. Methods We used the zymosan-induced arthritis (ZIA) model in wild-type and Il23p19 −/− mice, by a radiation chimera approach, and by single cell RNAseq and qPCR analyses, to identify the IL23p19-expressing and IL-23-responding cell type(s) in the inflamed joints. This model was also utilized to investigate the efficacy of IL-23p19 subunit blockade with a neutralizing monoclonal antibody (mAb). A novel IL-23-driven arthritis model was established, allowing the identification of putative downstream mediators of IL-23 in the control of pain and disease. Pain and arthritis were assessed by relative static weight distribution and histology, respectively. Results We present evidence that (i) IL-23p19+ non-bone marrow-derived macrophages are required for the development of ZIA pain and disease, (ii) prophylactic and therapeutic blockade of the IL-23p19 subunit ameliorate ZIA pain and disease and (iii) systemically administered IL-23 can induce arthritic pain and disease in a manner dependent on TNF, GM-CSF, CCL17 and cyclooxygenase activity, but independently of lymphocytes, CGRP, NGF and substance P. Conclusions The data presented should aid IL-23 targeting both in the choice of inflammatory disease to be treated and the design of clinical trials.

Abstract The interleukin (IL)-23 pathway is a pathogenic driver in psoriasis, psoriatic arthritis, and inflammatory bowel disease. Currently, no oral therapeutics selectively target this pathway. JNJ-77242113 is a peptide targeting the IL-23 receptor with high affinity (KD: 7.1 pM). In human cells, JNJ-77242113 potently and selectively inhibited proximal IL-23 signaling (IC50: 5.6 pM) without impacting IL-12 signaling. JNJ-77242113 inhibited IL-23–induced interferon (IFN)γ production in NK cells, and in blood from healthy donors and psoriasis patients (IC50: 18.4, 11 and 9 pM, respectively). In a rat trinitrobenzene sulfonic acid-induced colitis model, oral JNJ-77242113 attenuated disease parameters at doses ≥ 0.3 mg/kg/day. Pharmacologic activity beyond the gastrointestinal tract was also demonstrated. In blood from rats receiving oral JNJ-77242113, dose-dependent inhibition of ex vivo IL-23–stimulated IL-17A production was observed. In an IL-23–induced rat skin inflammation model, JNJ-77242113 inhibited IL-23–induced skin thickening and IL-17A, -17F and -22 gene induction. Oral dosing of JNJ-77242113 in healthy human volunteers inhibited ex vivo IL-23–stimulated IFNγ production in whole blood. Thus, JNJ-77242113 provided selective, systemic IL-23 pathway inhibition in preclinical models which translated to pharmacodynamic activity in healthy human volunteers, supporting the potential for JNJ-77242113 as a selective oral therapy for IL-23–driven immune-mediated diseases.

Attrition of first-year university students remains a global problem, and this is also of great concern in South African higher education. In an effort to address this challenge, many higher education institutions offer peer mentoring programmes to assist first-year students with their adjustment to university life, in order to improve their retention. However, evidence of the effectiveness of such peer mentoring programmes is still limited. This article intends to contribute in this regard. Stellenbosch University introduced its BeWell Peer Mentoring programme in 2013. In addition to providing psycho-social support, mentors offer developmental initiatives on holistic wellness to assist first-year students with their adjustment. After an institution-wide roll-out of the programme, the question arose whether the BeWell Peer Mentoring programme actually assisted first-year students in adjusting to campus life. In order to answer this question a research study with a sequential mixed-method design was employed. Our study found that adjustment outcomes were influenced by the intensity of peer mentoring participating students received. Mentor attributes, time invested in mentoring, reasons for mentoring and the wellness component of the programme all influenced the peer mentoring received. The findings underscored the importance of selecting intentional mentors, and effective programme implementation and monitoring. A model for intentional peer mentoring is proposed, to optimise the programme outcomes. Other institutions with similar programmes could also benefit from the proposed model.

Institutions of higher education play a critical role in bridging academia and workforce, yet college students find it challenging to transfer their learning across and beyond instructional formats, including online, hybrid, and face-to-face. The goals of this exploratory, sequential, mixed-methods study were to: (1) explore graduate students' conceptualizations of transfer; and (2) examine online pedagogical practices for enhancing transfer. Participants included students enrolled in a full-time online graduate degree program in education at a private university in the Mid-Atlantic USA. Findings from the qualitative phase with seven semi-structured interviews were used to design a survey study with 68 graduate students to explore their perceptions of effective online pedagogical practices for enhancing transfer. This study is significant since its findings revealed a number of online practices that instructional designers and faculty can use to optimize learning and transfer in higher education.

Bacterial brown spot (BBS) caused by Pseudomonas syringae pv. syringae (Pss), common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) and Xanthomonas fuscans subsp. fuscans (Xff), and halo bacterial blight (HBB), caused by Pseudomonas syringae pv. phaseolicola (Psph), are major bacterial diseases that severely affect common bean yields and global food security. Andean-origin dry beans, representing large-seeded market classes, are particularly susceptible. Using 140,325 SNPs, a multi-locus GWAS was conducted on subsets of the Andean diversity panel (ADP) phenotyped for BBS in South Africa, CBB in Puerto Rico, South Africa, and Zambia, and HBB in South Africa, through natural infection, artificial inoculation, or both. Twenty-four QTL associated with resistance were identified: nine for BBS, eight for CBB, and seven for HBB. Four QTL intervals on Pv01, Pv03, Pv05, and Pv08 overlapped with BBS and HBB resistance. A genomic interval on Pv01, near the fin gene, which determines growth habit, was linked to resistance to all three pathogens. Different QTLs were detected for BBS and CBB resistance when phenotyped under natural infection versus artificial inoculation. These results underscore the importance of combining phenotyping methods in multi-GWAS to capture the full genetic spectrum. Previously recognized CBB resistance QTL SAP6 and SU91 and HBB resistance QTL HB4.2, and HB5.1, were observed. Other common (MAF >0.25) and rare (MAF

Background: Foresight can be used to define futuristic orientated research and development (RD) that is required to position the road transport sector for a challenging future. Objectives: To develop a set of futuristic RD projects that could be added to a balanced SANRAL RD portfolio to position SANRAL and the transport sector for the future on a 15-year horizon. Method: Inputs into and ranking of the drivers, trends and technologies that will impact the transport sector were obtained from interviews with eminent thinkers, participants in workshops and a survey leading to five potential future scenarios. Qualitative and quantitative data analysis yielded several key solutions (KSs) and key interventions (KIs) to position the sector. This was complemented with the novel use of technology trees to analyse the linkages between new and existing knowledge and to identify gaps in knowledge and subsequently the identification of key RD opportunities. Results: Through backcasting from the desired future scenario as well as using 412 stakeholder inputs, 12 KSs and 61 KIs were defined and ranked. The top 30, most futuristic KIs were analysed using 18 hierarchical technology trees to define RD opportunities. Conclusion: The analysis emphasised the importance of new technologies such as data science, machine learning, smart transport and advanced materials to position the sector. Contribution: The use of a novel, structured technology foresight approach that utilises scenario development combined with hierarchical technology trees was demonstrated. To position the road transport sector for a challenging future, 12 new thematic KSs and 61 KIs were developed.