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Computational evaluation of Khaya ivorensis against plasmodium falciparum aminopeptidase N (PfM1AP) enzyme: molecular docking, simulation and ADMET studies
No full textThe extract obtained from the stem bark of Khaya ivorensis has been utilized for malaria treatment. Given the rising resistance of malaria parasites to current medications, exploring new pharmacological targets is essential. Metalloaminopeptidases, particularly PfM1AP, have been identified as promising targets due to their vital role in the survival of the parasite. This study employed computational modeling to evaluate the binding affinities and interaction characteristics of 165 compounds found in K. ivorensis with PfM1AP. The top five compounds showed binding affinities ranging from −18.306 to −13.073 kcal/mol, significantly higher than the standard ligand's − 7.97 kcal/mol. Among these, pentagalloylglucose displayed the strongest binding affinity and most stable interactions, suggesting its potential as a PfM1AP inhibitor. ADMET analysis revealed some limitations regarding oral bioavailability and permeability through the blood-brain barrier; however, these compounds exhibited favorable safety profiles with low predicted toxicity levels. Despite the pharmacokinetic challenges, their high binding affinities and stable interactions indicate their potential as effective antimalarial agents. These results highlight the need for further experimental validation and optimization to improve the drug-like properties of these compounds, particularly concerning bioavailability and pharmacokinetic issues. Ultimately, this research contributes to the growing body of work aimed at developing innovative antimalarial treatments and lays the groundwork for future studies focused on targeted approaches against malaria
Sustainability assessment of succinic acid production using the biochar-mediated anaerobic fermentation
No full textSuccinic acid is a bulk compound, which has been widely used in various areas. The anaerobic production of succinic acid by Escherichia coli suffers from the insufficient supply of reducing power, leading to the low titer and yield. This work adopted modified biochar to enhance bio-succinic acid production by E. coli Suc260. The integration of anaerobic fermentation with supplementation of cost-effective biochar in medium resulted in the highest succinic acid titer of 72.84 g/L along with reduced by-product, representing a remarkable yield of 93.03 %. Furthermore, results from Fourier transform infrared spectroscopy and scanning electron microscopy revealed the successful microbial attachment and growth within the biochar matrix. Notably, the addition of biochar enhanced the intracellular electron transport chain and maintained the intracellular metabolic balance, directing more metabolic flux towards the succinic acid synthesis. The energy and life-cycle assessment indicated that the energy consumption of the biochar-mediated fermentative succinic acid production process was 8.76 MJ/kgSA, and this process achieved a net negative carbon footprint of −0.651 kgCO2e/kgSA. This research highlights the great potential to leverage biochar for improving succinic acid biosynthesis through anaerobic fermentation. [Display omitted] •Biochar addition reduced acetic and formic acid by-product accumulation.•Fruitwood biochar most effectively promoted succinic acid production.•Biochar enhanced cell immobilization, pH buffering, and electron transfer.•The biochar-mediated process achieved net negative carbon emissions
Assessment of prescribing practices in community pharmacies in Windhoek, Namibia: a focus on antibiotics
No full textGlobally, medicine misuse is not something to be taken lightly. Moreover, the accelerated occurrence of antibiotic resistance is related to imprudent antibiotic use, which is extremely concerning. Low- and middle-income countries, like Namibia, are particularly vulnerable to misuse of medicines. Medicine use practices in public health settings often vary from those in private health settings, and in Namibia, whilst there is reasonable data on medicine use in public facilities, very little is available on the same in private facilities. Aim This study assessed the prescribing patterns in community pharmacies in Windhoek, Namibia, focussing on antibiotics to gauge the magnitude of the problem. A retrospective cross-sectional study was conducted using an adapted, validated WHO methodology. The study population consisted of all community pharmacies in Windhoek and the prescriptions for one year before the study. A multi-stage sampling method was used, with a stratification technique to randomly select 25 out of 71 community pharmacies and a systematic random technique to select 108 prescriptions per pharmacy, making a total of 2700 prescriptions. Data was retrospectively captured by the researcher and two trained research assistants using two data collection forms adapted from WHO-validated tools. Data analysis was conducted using the latest version of IBM’s Statistical Package for Social Sciences (IBM/SPSS/Statistics/28.0) to describe prescribing indicators and identify irrational use practices, including antibiotic use patterns
Strengthening parental capabilities: Examining the role of interdisciplinary support in enhancing parental well-being and capabilities in developmental disability care
No full textPurpose: The purpose of this study was to explore parents’ lived experiences raising children with developmental disabilities (DDs), examine their emotional and physical challenges, and investigate the role of interdisciplinary support in strengthening parental capabilities. Materials and Methods: A qualitative descriptive study was conducted using two focus groups (n = 23 parents). Data were analyzed using Braun and Clarke’s six-step thematic analysis. Results: Five major themes emerged: (1) acceptance and emotional journey, (2) healthcare system navigation challenges, (3) educational and community integration barriers, (4) the development of coping strategies and support systems, and (5) resilience and positive growth. Parents reported significant emotional challenges but demonstrated remarkable resilience when supported by comprehensive care systems. Conclusions: The findings highlight the need for integrated support systems that address both the practical and emotional needs of parents raising children with DDs. Healthcare providers and community stakeholders must work collaboratively to create more inclusive and supportive environments for these families
Exploring university students' subjective experiences of stress, coping, perceived social support, and psychological well-being in the context of teaching and learning during COVID-19
No full textThe COVID-19 pandemic has significantly impacted the lives of individuals globally, and university students have faced unique challenges due to disruptions in their academic, social, and personal lives. In a pre-COVID-19 survey, first-year students from 19 universities in 8 countries (Australia, Belgium, Germany, Mexico, Northern Ireland, South Africa, Spain, and the United States) had prevalence rates for suicidal ideation, plan, and attempt of 17.2%, 8.8%, and 1.0%, respectively over a 12-month period. University enrolment is an important moment when students face new obstacles such as making independent decisions, adjusting to academic expectations, and developing relationships with unfamiliar people. This research is important to understand how to encourage mental health in different populations. Students experience new problems after moving into the university setting, including decision-making, adjusting to academic obligations, and socializing with strangers. Located within Lazarus and Folkman’s Transactional Model of Stress and Coping (TMSC) as a framework, the present study used qualitative research methods, the present study aimed to explore the subjective experiences of stress, coping strategies, perceived social support, and psychological well-being among university students within the context of teaching and learning in the COVID-19 pandemic at a university in the Western Cape. Semi-structured, individual interviews were conducted to gain deeper insights into subjective experiences of stress, coping strategies, perceived social support, and psychological well-being among university students. The Humanities and Social Sciences Research Ethics Committee (HSSREC) approved the research before it was conducted at the University of the Western Cape (Ethics reference: HS23/7/34; Appendix A). The Office of the Registrar granted institutional permission to conduct research on students. The present study complied with all applicable data protection laws, including the Protection of Personal Information Act (POPIA), and the University’s Research Policy and Data
Management Policy
MIGHTEE-HI: the radial acceleration relation with resolved stellar mass measurements
No full textThe radial acceleration relation (RAR) is a fundamental relation linking baryonic and dark matter in galaxies by relating the observed acceleration derived from dynamics to the one estimated from the baryonic mass. This relation exhibits small scatter, thus providing key constraints for models of galaxy formation and evolution – allowing us to map the distribution of dark matter in galaxies – as well as models of modified dynamics. However, it has only been extensively studied in the very local Universe with largely heterogeneous samples. We present a new measurement of the RAR, utilizing a homogeneous sample of 19 H i-selected galaxies out to . We introduce a novel approach of measuring resolved stellar masses using spectral energy distribution fitting across 10 photometric bands to determine the resolved mass-to-light ratio, which we show is essential for measuring the acceleration due to baryons in the low-acceleration regime. Our results reveal a tight RAR with a low-acceleration power-law slope of , consistent with previous studies. Adopting a spatially varying mass-to-light ratio yields the tightest RAR with an intrinsic scatter of only dex, highlighting the importance of resolved stellar mass measurements in accurately characterizing the gravitational contribution of the baryons in low-mass, gas-rich galaxies. We also find the first tentative evidence for redshift evolution in the acceleration scale, but more data will be required to confirm this. Adopting a more general MOND interpolating function, we find that our results ameliorate the tension between previous RAR analyses, the Solar System quadrupole, and wide-binary test
The jet paths of radio active galactic nuclei and their cluster weather
No full textWe studied bent radio sources within X-ray galaxy groups in the COSMOS and XMM-LSS fields. The radio data were obtained from the MeerKAT International GHz Tiered Extragalactic Explorations data release 1 (MIGHTEE-DR1) at 1.2-1.3 GHz, with angular resolutions of 8.9″ and 5″, and median noise levels of rmsmed ∼= 3.5 and 5.5 μJy/beam. Bent radio active galactic nuclei (AGN) were identified through visual inspection. Our analysis included 19 bent radio AGN in the COSMOS field and 17 in the XMM-LSS field that lie within X-ray galaxy groups (2 × 1013 ≲ M200c/M⊙ ≤ 3×1014). We investigated the relationship between their bending angle (BA) - the angle formed by the jets or lobes of two-sided radio sources associated with AGN - and the properties of their host galaxies and large-scale environment probed by the X-ray galaxy groups. Our key findings are: (a) In the XMM-LSS field, we observed a strong correlation between the linear projected size of the bent AGN, the group halo mass, and the projected distance from the group centre. This trend, consistent with previous studies, was not detected in the COSMOS sample. (b) The BA is a function of environmental density, with the type of medium playing a significant role. Additionally, at z ≤ 0.5 we found a higher number of bent sources (BA ≤ 160°) compared to higher redshifts (z ∼ 1), by a factor of >1.5. This trend aligns with magneto-hydrodynamic simulations, which suggest that denser environments and longer interaction times at lower redshifts contribute to this effect. A comparison with the literature suggests that jet bending in galaxy groups within the redshift range 0.1 < z < 1.2 is primarily driven by ram pressure exerted on the jets, which occurs during quiescent phases of AGN activity. This study underscores the role of environmental interactions in shaping the morphology of radio AGN within galaxy groups, providing insights into the interplay between large-scale structure and AGN physics
Towards cosmological inference on unlabeled out-of-distribution hi observational data
No full textWe present an approach that can be utilized in order to account for the covariate shift between two datasets of the same observable with different distributions. This helps improve the generalizability of a neural network model trained on in-distribution samples (IDs) when inferring cosmology at the field level on out-of-distribution samples (OODs) of unknown labels. We make use of HI maps from the two simulation suites in CAMELS, IllustrisTNG and SIMBA. We consider two different techniques, namely adversarial approach and optimal transport, to adapt a target network whose initial weights are those of a source network pre-trained on a labeled dataset. Results show that after adaptation, salient features that are extracted by source and target encoders are well aligned in the embedding space. This indicates that the target encoder has learned the representations of the target domain via the adversarial training and optimal transport. Furthermore, in all scenarios considered in our analyses, the target encoder, which does not have access to any labels (Ωm) during adaptation phase, is able to retrieve the underlying Ωm from out-of-distribution maps to a great accuracy of R2 score ≥ 0.9, comparable to the performance of the source encoder trained in a supervised learning setup. We further test the viability of the techniques when only a few out-of-distribution instances are available for training and find that the target encoder still reasonably recovers the matter density. Our approach is critical in extracting information from upcoming large scale surveys
The first record of Cape Clawless Otters Aonyx capensis predating on African Penguins Spheniscus demersus
No full textThe African Penguin Spheniscus demersus, a critically endangered seabird endemic to southern Africa, faces substantial threats from terrestrial predators at its mainland colonies. Correct identification of the predator species is essential for effective conservation management. This study provides the first documented evidence of Cape Clawless Otter Aonyx capensis predation on African Penguins. We describe characteristic lesion patterns distinguishing otter predation from other predators, such as Caracal Caracal caracal. These findings underscore the importance of accurate predator identification to guide targeted mitigation strategies and highlight the need for adaptive management to protect vulnerable mainland African Penguin colonies from emerging predation pressures
Strong polymer-cellulose interfacial engineering enables hydrogel-enhanced separators with multiscale networks for zinc-ion batteries
No full textCellulose paper-based separators have attracted significant attention as promising materials for aqueous zinc ion batteries (ZIBs) owing to their excellent wettability, chemical stability, and environmental compatibility. However, water molecules penetrate into the amorphous regions of cellulose to induce plasticization, thus increasing the mobility of molecular chains and disrupting the intermolecular hydrogen bonding within cellulose. This degradation mechanism severely deteriorates battery cycling performance and capacity retention, thereby hindering the utility of cellulose paper-based separators in aqueous ZIBs. Herein, we propose an in situ photo-initiated radical polymerization strategy to integrate acrylamide-nanocellulose hydrogels onto cellulose separators, resulting in the construction of hydrogel-coated composite separators. In this design, the strong polymer-cellulose interfacial interactions restrict cellulose chain mobility, homogenize Zn2+ ion flux, and significantly enhance wet-state mechanical robustness. Consequently, the composite separator ensures structural integrity during prolonged cycling. The assembled Zn|PNF-6|V2O5 full cell demonstrates superior cycle stability, retaining a capacity retention of 80 % over 4000 cycles at 5 A g−1. This work pioneers a scalable route toward high-performance hydrogel-enhanced paper separators, addressing critical challenges for ZIBs industrialization