Calibrated cryo-cell UV-LA-ICPMS elemental concentrations from the NGRIP ice core reveal abrupt, sub-annual variability in dust across the GI-21.2 interstadial period

Several abrupt shifts from periods of extreme cold (Greenland stadials, GS) to relatively warmer conditions (Greenland interstadials, GI) called Dansgaard–Oeschger events are recorded in the Greenland ice cores. Using cryo-cell UV-laser-ablation inductively coupled-plasma mass spectrometry (UV-LA-ICPMS), we analysed a 2.85 m NGRIP ice core section (2691.50–2688.65 m depth, age interval 84.86–85.09 ka b2k, thus covering  ∼  230 years) across the transitions of GI-21.2, a short-lived interstadial prior to interstadial GI-21.1. GI-21.2 is a  ∼  100-year long period with δ18O values 3–4 ‰ higher than the following  ∼  200 years of stadial conditions (GS-21.2), which precede the major GI-21.1 warming. We report concentrations of major elements indicative of dust and/or sea salt (Na, Fe, Al, Ca, Mg) at a spatial resolution of  ∼  200 µm, while maintaining detection limits in the low-ppb range, thereby achieving sub-annual time resolution even in deep NGRIP ice. We present an improved external calibration and quantification procedure using a set of five ice standards made from aqueous (international) standard solutions. Our results show that element concentrations decrease drastically (more than 10-fold) at the warming onset of GI-21.2 at the scale of a single year, followed by relatively low concentrations characterizing the interstadial part before gradually reaching again typical stadial values

Third wave of asbestos-related disease from secondary use of asbestos: A case report from industry

An occupational health survey conducted in a workshop in which asbestos cement was used showed initial atmospheric asbestos levels ranging frm 1,9 to 27,5 fibres per millilitre of air. Radiological changes suggestive of asbestos-related pleural disease were found in 2 workers (2,5%), while 3 (3,8%) had borderline features of asbestosis. The survey confinned that uncontrolled and hazardous use of asbestos continues in industry despite public awareness of its dangers and the Asbestos Regulations of 1987

Antibacterial and dermal toxicological profiles of ethyl acetate extract from Crassocephalum bauchiense (Hutch.) Milne-Redh (Asteraceae)

<p>Abstract</p> <p>Background</p> <p>The emergence in recent years of numerous resistant strains of pathogenic bacteria to a range of formerly efficient antibiotics constitutes a serious threat to public health. <it>Crassocephalum bauchiense</it>, a medicinal herb found in the West Region of Cameroon is used to treat gastrointestinal infections as well as liver disorders. The ethyl acetate extract from the leaves of <it>C. bauchiense </it>was evaluated for its antibacterial activity as well as acute and sub-acute toxicities.</p> <p>Methods</p> <p>The plant extract was prepared by maceration in ethyl acetate. Its phytochemical screening was done by standard methods. The broth microdilution method was used to evaluate the <it>in vitro </it>antibacterial activity. The <it>in vivo </it>antibacterial activity of a gel formulation (0.05, 1 and 2% w/v) of this extract was evaluated using a <it>Staphylococcus aureus</it>-induced dermatitis in a murine model. Selected haematological and biochemical parameters were used to evaluate the dermal sub-acute toxicity of the extract in rats.</p> <p>Results</p> <p>Phytochemical screening of the <it>C. bauchiense </it>extract revealed the presence of alkaloids, phenols, tannins and sterols. <it>In vitro </it>antibacterial activities were observed against all the tested microorganisms (MIC = 0.04-6.25 mg/ml). Formulated extract-gel (2% w/v) and gentamycin (reference drug) eradicated the microbial infection after five days of treatment. A single dermal dose of this extract up to 32 g/kg body weight (bw) did not produce any visible sign of toxicity. Also, daily dermal application of the <it>C. bauchiense </it>extract gel formulation for 28 days did not show any negative effect, instead some biochemical parameters such as alanine aminotransferase (ALT and AST), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides were significantly (p < 0.05) affected positively.</p> <p>Conclusion</p> <p>These results indicate that the <it>C. bauchiense </it>ethyl acetate extract can be used safely for the treatment of some bacterial infections.</p

Antimicrobial and antioxidant properties of methanol extract, fractions and compounds from the stem bark of Entada abyssinica Stend ex A. Satabie

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to evaluate the antimicrobial and antioxidant activities of the methanol extract, fractions and isolated compounds from <it>Entada abyssinica </it>stem bark, plant used traditionally against gastrointestinal infections.</p> <p>Methods</p> <p>The methanol extract of <it>E. abyssinica </it>stem bark was pre-dissolved in a mixture of methanol and water, and then partitioned between <it>n</it>-hexane, ethyl acetate and <it>n</it>-butanol. The ethyl acetate portion was fractionated by column chromatography and the structures of isolated compounds elucidated by analysis of spectroscopic data and comparison with literature data. Antimicrobial activity was assayed by broth microdilution techniques on bacteria and yeasts. The antioxidant activity was determined by DPPH radical scavenging method.</p> <p>Results</p> <p>Four known compounds [(5<it>S</it>,6<it>R</it>,8a<it>R</it>)-5-(carboxymethyl)-3,4,4a,5,6,7,8,8a-octahydro-5,6,8a-trimethylnaphthalenecarboxylic acid (<b>1</b>), methyl 3,4,5-trihydroxybenzoate (<b>2</b>), benzene-1,2,3-triol (<b>3</b>) and 2,3-dihydroxypropyltriacontanoate (<b>4</b>)] were isolated. Compared to the methanol extract, fractionation increased the antibacterial activities of the <it>n</it>-hexane and ethyl acetate fractions, while the antifungal activities increased in ethyl acetate, <it>n</it>-butanol and aqueous residue fractions. The isolated compounds were generally more active on bacteria (9.7 to 156.2 μg/ml) than yeasts (78.1 to 312.5 μg/ml). Apart from compound <b>1</b>, the three others displayed DPPH^·scavenging activity (RSa), with RSa₅₀values of 1.45 and 1.60 μg/ml.</p> <p>Conclusion</p> <p>The results obtained from this study support the ethnomedicinal use of <it>E. abyssinica </it>in the treatment of gastrointestinal infections and the isolated compounds could be useful in the standardisation of antimicrobial phytomedicine from this plant.</p

Towards a holistic approach to support learners at risk of interrupted development

The COVID-19 pandemic and the restrictions that came with it led to unprecedented disruptions in learner development and put them at risk of poor developmental outcomes. It is thus important that the extent of the disruption on their development and the support needs of learners be investigated. Researching the impact of the disruption should focus on holistic development. In this book, the authors use multiple research approaches and methods of gathering data in their respective fields to examine the impact of the disruption and determine the support needs of learners. Data gathered through the different methods are processed and findings are presented. The findings have implications for both practice and future research in the fields of inclusive education, learner support, educational psychology, movement education, Life Orientation and curriculum development

Novobiocin–ferrocene conjugates possessing anticancer and antiplasmodial activity independent of HSP90 inhibition.

A series of tailored novobiocin–ferrocene conjugates was prepared in moderate yields and investigated for in vitro anticancer and antiplasmodial activity against the MDA-MB-231 breast cancer line and Plasmodium falciparum 3D7 strain, respectively. While the target compounds displayed moderate anticancer activity against the breast cancer cell line with IC50 values in the mid-micromolar range, compounds 10a–c displayed promising antiplasmodial activity as low as 0.889 µM. Furthermore, the most promising compounds were tested for inhibitory effects against a postulated target, heat shock protein 90 (Hsp90)

Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

Multidimensional nonlinear embedding models for image scene dimensionality reduction and visualization

Many pattern recognition applications rely on building decision making models based on meaningful and often hidden patterns of real world objects represented as points in a high dimensional feature space. Such a space presents great opportunities, as well as computational modeling hurdles that include the curse of dimensionality. Assumptions are often made, and more challenges encountered in easing the difficulty of analyzing and interpreting such data. The first step could be to assume that regular data information resides on a lower dimensional manifold. An immediate challenge is how to design mapping models such that the nonlinear relationships in observations are captured by Euclidean or non-Euclidean manifolds. Furthermore, can there be a general nonlinear embedding framework whose platform has functional properties for building new solutions to the problem of dimensionality reduction? To address these challenges, this thesis embarks on three fronts to provide and develop efficient nonlinear dimensionality algorithms by exploiting the regularity details within image scenes. First, it presents a non-Euclidean spherical stochastic neighbor embedding technique for the purposes of mapping data whose similarity spectrum suggests a nonzero negative eigenfraction. Secondly, the study presents a general framework based on the dynamic equations described by gradient potential fields. The framework incorporates a force field intuition to seek a minimum energy configuration state of a neighborhood graph. Thirdly, the platform is applied to propose novel unsupervised multidimensional artificial field embedding techniques that rely on the intuitive superposition of pair-dependent quadratic distance attraction and inverse-distance repulsion functions. The proposed models provide capabilities that preserve the local topology of data and establish significant discriminatory boundaries between different structures. Experimental investigations for visualization, gradient field trajectories, and semisupervised classification on remote sensing and computer vision images demonstrate the superiority of the proposed models over current state-of-art methods

A postcolonial ecofeminist comparative analysis of war fiction: The case of Arundhati Roy's The God of small and Chimamanda Ngozi Adichie's Half of a yello sun

A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Arts in English StudiesThe main focus of the study was to comparatively analyse The God of Small Things (1997) by Arundhati Roy and Half of a Yellow Sun (2006) by Chimamanda Ngozi Adichie from a postcolonial ecofeminist perspective. Postcolonialism focuses on issues pertaining to power, culture, and religion in relation to humanity, whilst ecofeminism explores the links between the environment and women, connecting women to the epistemological understanding of nature. The research aimed at exploring the plight of women and the environment in a wartime postcolonial era through the literary lens. The application of postcolonialism and ecofeminism to the analysis of the texts necessitated the consideration and inclusion of themes such as; hybridity, gender trauma, subjugation, relationships and beliefs. The study is a desktop qualitative research and it employed content analysis in the interpretation and analysis of the two novels. Women were portrayed as destitute who stay in subservient conditions, at the mercy of patriarchal societies, with no voice; sex objects for the husband’s pleasures and that can be exchanged for material wealth. Nature is used as an agent of resistance in The God of Small Things (1997). For instance, Ammu uses the Meenachal River as an escape from patriarchal entrapment and psychological imprisonment where she goes to find peace and listen to her transistor. In Half of a Yellow Sun, Kainene profits from the civil war in the beginning, later becoming conscientious to the needs of the less fortunate and women are subjugated by both white and black male counterparts through exploitation by both the mercenaries and Biafra soldiers. Contrariwise, Roy and Adichie depict women as perceptive and sensible thinkers. In The God of Small Things, Ammu is protective of her naïve children because she is well aware of the evils of this world, most of which she herself has been a victim of. The study found that by reading The God of Small Things (1997) and Half of a Yellow Sun (2006) as contemporaries, there can be testament to some wealthy accounts as the novels provide a coherent shape of the realistic operations of postcolonial ecofeminism in totality. The thrust of this study is to draw interconnections between men’s domination of nature and the subjugation and dominance of women as depicted in the selected creative works. The study concluded that future studies need to consider the use of ecofeminism as a theory in the analysis of novels; merging ecofeminism with other theories in other genres such as poetry, drama and genocidal literature in the analysis of different literary works