Understanding learner attitudes towards the use of tablets in a blended learning classroom

In 2004, the South African Department of Education (DoE) published the White Paper on E-Education. The aim of the E-Education White Paper was to ensure that South African learners could use education communication technologies (ECT) skilfully by 2013. However, these goals have not been met and a significant digital divide exists between learners with and without access to ET. The lack of consideration of intra- and inter-personal factors such as attitudes in the rollout of ET has often been cited as one of the reasons for the present lack of ET integration and uptake in schools. Hence, this study contributes to this gap in research by exploring attitudes towards the use of iPads in a sample of South African learners in a blended learning environment. A demographic questionnaire and the ET Attitudes Scale were administered to a convenience sample of 285 learners from a private school in the Johannesburg area. Descriptive statistics, ANOVAs and thematic analysis were used to analyse the results. From the findings, it was evident that overall learners were more positive than negative about the integration of iPads in school. However, this pattern differed across the grades with lower grades demonstrating better attitudes towards the use of iPads in terms of enjoyability, ease of use and usefulness. These results suggest that ET attitudes do have a role to play in order to ensure the successful implementation and adoption of ET by learners and should be considered in policy and practice

Differential Producibility Analysis (DPA) of Transcriptomic Data with Metabolic Networks: Deconstructing the Metabolic Response of M. tuberculosis

A general paucity of knowledge about the metabolic state of Mycobacterium tuberculosis within the host environment is a major factor impeding development of novel drugs against tuberculosis. Current experimental methods do not allow direct determination of the global metabolic state of a bacterial pathogen in vivo, but the transcriptional activity of all encoded genes has been investigated in numerous microarray studies. We describe a novel algorithm, Differential Producibility Analysis (DPA) that uses a metabolic network to extract metabolic signals from transcriptome data. The method utilizes Flux Balance Analysis (FBA) to identify the set of genes that affect the ability to produce each metabolite in the network. Subsequently, Rank Product Analysis is used to identify those metabolites predicted to be most affected by a transcriptional signal. We first apply DPA to investigate the metabolic response of E. coli to both anaerobic growth and inactivation of the FNR global regulator. DPA successfully extracts metabolic signals that correspond to experimental data and provides novel metabolic insights. We next apply DPA to investigate the metabolic response of M. tuberculosis to the macrophage environment, human sputum and a range of in vitro environmental perturbations. The analysis revealed a previously unrecognized feature of the response of M. tuberculosis to the macrophage environment: a down-regulation of genes influencing metabolites in central metabolism and concomitant up-regulation of genes that influence synthesis of cell wall components and virulence factors. DPA suggests that a significant feature of the response of the tubercle bacillus to the intracellular environment is a channeling of resources towards remodeling of its cell envelope, possibly in preparation for attack by host defenses. DPA may be used to unravel the mechanisms of virulence and persistence of M. tuberculosis and other pathogens and may have general application for extracting metabolic signals from other “-omics” data

Both alpha- and beta-rhizobia occupy the root nodules of Vachellia karroo in South Africa

Vachellia karroo (formerly Acacia karroo) is a wide-spread legume species indigenous to southern Africa. Little is known regarding the identity or diversity of rhizobia that associate with this plant in its native range in South Africa. The aims of this study were therefore: (i) to gather a collection of rhizobia associated with V. karroo from a wide range of geographic locations and biomes; (ii) to identify the isolates and infer their evolutionary relationships with known rhizobia; (iii) to confirm their nodulation abilities by using them in inoculation assays to induce nodules under glasshouse conditions. To achieve these aims, soil samples were collected from 28 locations in seven biomes throughout South Africa, which were then used to grow V. karroo seedlings under nitrogen-free conditions. The resulting 88 bacterial isolates were identified to genus-level using 16S rRNA sequence analysis and to putative species-level using recA-based phylogenetic analyses. Our results showed that the rhizobial isolates represented members of several genera of Alphaproteobacteria (Bradyrhizobium, Ensifer, Mesorhizobium, and Rhizobium), as well as Paraburkholderia from the Betaproteobacteria. Our study therefore greatly increases the known number of Paraburkholderia isolates which can associate with this southern African mimosoid host. We also show for the first time that members of this genus can associate with legumes, not only in the Fynbos biome, but also in the Albany Thicket and Succulent Karoo biomes. Twenty-six putative species were delineated among the 88 isolates, many of which appeared to be new to Science with other likely being conspecific or closely related to E. alkalisoli, M. abyssinicae, M. shonense, and P. tropica. We encountered only a single isolate of Bradyrhizobium, which is in contrast to the dominant association of this genus with Australian Acacia. V. karroo also associates with diverse genera in the Grassland biome where it is quite invasive and involved in bush encroachment. Our findings therefore suggest that V. karroo is a promiscuous host capable of forming effective nodules with both alphaand beta-rhizobia, which could be a driving force behind the ecological success of this tree species.The National Research Foundation (NRF) of South Africahttp://www.frontiersin.org/Microbiologyam2020BiochemistryGeneticsMicrobiology and Plant Patholog

Percutaneous embolization of lymphatic fistulae as treatment for protein-losing enteropathy and plastic bronchitis in patients with failing Fontan circulation

BACKGROUND: To determine the feasibility and clinical result of selective embolization of hepatoduodenal or paratracheal lymphatics in Fontan patients with protein-losing enteropathy (PLE) or plastic bronchitis (PB). METHODS: Dilated lymph vessels in periportal (PLE) or paratracheal (PB) position were percutaneously punctured with a 22G Chiba needle. Intralymphatic position was confirmed by water soluble contrast injection with drainage to hepatoduodenal or tracheal fistulae. After flushing with 10% glucose solution, occlusion of hepatoduodenal or paratreacheal lymphatics was effected by injection of 1-4 cc mixture 4/1 of Lipiodol/n-butyl cyanoacrylate (n-BCA; Histoacryl). RESULTS: Seven patients with proven PLE were treated with periportal lymphatic embolization 10.7 (range: 6.6-13.5) years after the Fontan operation. The Fontan operation was performed at a median age of 3.7 (range: 2.9-5.7) years and PLE started a median of 3.1 (range: 0.9-4.7) years later. Five patients required a second procedure 2-8 months later. Complications were limited (spillage of glue in portal branch, transient cholangitis, and caustic duodenal bleeding). Six of seven patients reported significant improvement in quality of life and normalization of albumin levels after limited follow-up (p < .01). One patient (Fontan at 2.9 years; age 16.4 years) had PB for 2 years. Selective transthoracic cone-beam-directed puncture of left and right paratracheal lymphatics with n-BCA embolization of distal lymphatic fistulae resulted in lasting absence of tracheal casts (11 months). CONCLUSIONS: Embolization of periportal/peritracheal lymphatics is a promising technique in Fontan patients with PLE/PB. Larger series are required to determine incidence and reasons of success/failure, with long-term results and effects on liver function.status: publishe

Quantifying the carbon footprint of clinical trials: guidance development and case studies

Background The urgency of the climate crisis requires attention from biomedical research, not least clinical trials which can involve significant greenhouse gas emissions. The Low Carbon Clinical Trials Working Group set out a strategy to reduce the emissions of clinical trials, starting with the development of a method to measure their carbon footprint (CO2e).Methods As a first step, we developed a process map defining clinical trial core activities. Corresponding emission factors were sourced to convert activity data into greenhouse gas emissions. The subsequent method was applied to two Cancer Research UK (CRUK)-funded trials (the international randomised sarcoma trial CASPS (ISRCTN63733470) and the UK cohort-based breast cancer trial PRIMETIME (ISRCTN41579286)). A guidance document defining the scope, method and assumptions was written to allow application to any publicly funded/investigator initiated clinical trial.Results Trial specific activities over and above routine care were grouped into 10 modules covering trial set up, conduct and closure. We identified emission factors for all trial activities within both trials and used them to estimate their total carbon footprint. The carbon footprint of CASPS, an international phase 2 trial of an investigational medicinal product with 47 participants, was 72 tonnes CO2e, largely attributable to clinical trials unit emissions and staff travel. PRIMETIME, a UK-based phase 3 non-investigational medicinal product trial with 1962 patients, produced 89 tonnes CO2e, largely attributable to trial-specific in-person participant assessments.Conclusion We have developed a method and guidance that trialists can use to determine the carbon footprint of clinical trials. The guidance can be used to identify carbon hotspots where alternative approaches to trial design and conduct could reduce a trial footprint, and where methodology research is required to investigate the potential impact of interventions taken to reduce carbon emissions. We will continue to refine the guidance to increase the potential application and improve usability

Structure–Activity Relationships of the MEPicides: <i>N</i>‑Acyl and <i>O</i>‑Linked Analogs of FR900098 as Inhibitors of Dxr from <i>Mycobacterium tuberculosis</i> and <i>Yersinia pestis</i>

Despite continued research efforts, the threat of drug resistance from a variety of bacteria continues to plague clinical communities. Discovery and validation of novel biochemical targets will facilitate development of new drugs to combat these organisms. The methylerythritol phosphate (MEP) pathway to make isoprene units is a biosynthetic pathway essential to many bacteria. We and others have explored inhibitors of the MEP pathway as novel antibacterial agents. <i>Mycobacterium tuberculosis</i>, the causative agent of tuberculosis, and <i>Yersinia pestis</i>, resulting in the plague or “black death”, both rely on the MEP pathway for isoprene production. 1-Deoxy-d-xylulose 5-phosphate reductoisomerase (Dxr) catalyzes the first committed step in the MEP pathway. We examined two series of Dxr inhibitors based on the parent structure of the retrohydroxamate natural product FR900098. The compounds contain either an extended <i>N</i>-acyl or <i>O</i>-linked alkyl/aryl group and are designed to act as bisubstrate inhibitors of the enzyme. While nearly all of the compounds inhibited both Mtb and Yp Dxr to some extent, compounds generally displayed more potent inhibition against the Yp homologue, with the best analogs displaying nanomolar IC₅₀ values. In bacterial growth inhibition assays, the phosphonic acids generally resulted in poor antibacterial activity, likely a reflection of inadequate permeability. Accordingly, diethyl and dipivaloyloxymethyl (POM) prodrug esters of these compounds were made. While the added lipophilicity did not enhance <i>Yersinia</i> activity, the compounds showed significantly improved antitubercular activities. The most potent compounds have Mtb MIC values of 3–12 μg/mL. Taken together, we have uncovered two series of analogs that potently inhibit Dxr homologues from Mtb and Yp. These inhibitors of the MEP pathway, termed MEPicides, serve as leads for future analog development

Protection of European domestic pigs from virulent African isolates of African swine fever virus by experimental immunisation

African swine fever (ASF) is an acute haemorrhagic disease of domestic pigs for which there is currently no vaccine. We showed that experimental immunisation of pigs with the non-virulent OURT88/3 genotype I isolate from Portugal followed by the closely related virulent OURT88/1 genotype I isolate could confer protection against challenge with virulent isolates from Africa including the genotype I Benin 97/1 isolate and genotype X Uganda 1965 isolate. This immunisation strategy protected most pigs challenged with either Benin or Uganda from both disease and viraemia. Cross-protection was correlated with the ability of different ASFV isolates to stimulate immune lymphocytes from the OURT88/3 and OURT88/1 immunised pigs