46 research outputs found

    Barriers affecting COVID‑19 vaccination in Phalombe District, Malawi: A qualitative study

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    Background. In Malawi, only 1 072 229 people out of a national target population of 13 546 324 had received at least one dose of the AstraZeneca COVID‑19 vaccine by 26 December 2021, and only 672 819 people were classified as fully vaccinated. Phalombe District in Malawi had particularly low COVID‑19 vaccine uptake, with only 4% (n=8 538) of 225 219 people being fully vaccinated by 26 December. Objectives. To explore reasons for vaccine hesitancy and refusal among people living in Phalombe District. Methods. This cross-sectional qualitative study employed six focus group discussions (FGDs) and 19 in-depth interviews (IDIs) to collect data. We purposefully selected two traditional authorities (TAs), Nazombe and Nkhumba, as study areas, and conducted FGDs and IDIs in 6 randomly selected villages in these two TAs. Participants were religious leaders, traditional leaders, youths, traditional healers and ordinary community members. We explored reasons for vaccine refusal and hesitancy, how contextual cultural beliefs influenced people’s decision to receive the COVID‑19 vaccine, and which sources of information were trusted in the community. Data were analysed using thematic content analysis. Results. We conducted 19 IDIs and six FGDs. Themes that emerged from the data were reasons for vaccine refusal and hesitancy, contextual cultural beliefs affecting the decision whether to be vaccinated, ways to improve COVID‑19 vaccine uptake, and means of communicating information about COVID‑19 vaccines. Participants mentioned that myths contributing to vaccine refusal and hesitancy circulated in the community through social media. With regard to contextual cultural beliefs, most participants believed that COVID‑19 was a disease of rich people, while others believed that it signalled the end of the world and that it could not be cured. Conclusion. Health systems should recognise and acknowledge the reasons leading to vaccine hesitancy and refusal and address these appropriately to improve vaccine uptake. Effective community sensitisation and engagement should be enhanced to clarify myths and address misinformation about the COVID‑19 vaccine

    Synthesis and photo electrochemical characterization of an extended π-conjugated heteroleptic ruthenium (II) complex

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    A new extended π-conjugate heteroleptic ruthenium(II) complex (m-HRD-1) that contains a 4,4'-bis-2-(5(3,5-di-tert-butylphenyl)thiophene-2-yl)vinyl)2,2'-bipyridine as ancillary ligand, 4,4’-dicaboxy-2,2'-bipyridine as anchoring group, and two thiocyanate ligands in its molecular structure have been designed, synthesized and characterized by CHN, Mass, 1H-NMR, UV-Vis, and fluorescence spectroscopies as well as cyclic voltammetry. Electrochemical and theoretical studies showed that the LUMO of the sensitizer is above TiO2 conduction band and the HOMO is below the redox potential of the electrolyte. This new sensitizer was tested in dye-sensitized solar cells using liquid redox couple (I-/I3-) and its performance was compared to the standard sensitizer N719

    Effect of sub-optimal moisture levels on the quality of groundnut (Arachis hypogaea L.) during storage in triple-layer hermetic storage bags

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    Storage is an important aspect of groundnut, as the in-shell and shelled kernels are prone to infestation by insects, pests, and fungi. Among several storage pests, the groundnut bruchid, Caryedon serratus, causes serious losses. Farmers often resort to different management practices, including hermetic storage, to control it. The moisture content of the commodity plays an important role in insect infestation during storage. Drying to safe moisture levels before storage is known to prevent the activity of various living organisms, such as storage pests. However, drying to low levels of moisture may not be economical for farmers, as they may not have access to devices to accurately check product moisture. In this regard, we wanted to demonstrate the efficacy of triple-layer hermetic storage bags in preventing the damage caused by C. serratus when the groundnuts are stored at intermediate (10%) and high (14%) levels of moisture compared to traditionally used bags such as polypropylene bags and jute bags. Groundnut pods at 10% moisture content and 14% moisture content were separately inoculated with adult bruchids and a toxigenic strain of Aspergillus flavus fungal inoculum before storing them for 6 months. Results from groundnut samples taken at two-month intervals indicated that groundnut pods stored in triple-layer hermetic bags were completely free from infestation by C. serratus by recording a zero number of eggs laid, number of pupae, adult emergence, percentage of loss, and percentage of damage up to 6 months of storage, by creating low oxygen (hypoxia) and high carbon dioxide (hypercarbia) conditions. Results also indicate no loss of pod weight stored in triple-layer bags, but a slight reduction in germination percentage was recorded due to a slight increase in fungal activity, but the reduction was significantly less in triple-layer plastic bags compared to other bag types. Similarly, biochemical constituents such as oil and protein content were slightly reduced in triple-layer plastic bags when pods were stored at a 10% moisture level, but a higher reduction was observed at a 14% moisture level. However, the reduction was very high and significant in other bag types at both 10 and 14% moisture levels

    Effect of sub-optimal moisture levels on the quality of groundnut (Arachis hypogaea L.) during storage in triple-layer hermetic storage bags

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    Storage is an important aspect of groundnut, as the in-shell and shelled kernels are prone to infestation by insects, pests, and fungi. Among several storage pests, the groundnut bruchid, Caryedon serratus, causes serious losses. Farmers often resort to different management practices, including hermetic storage, to control it. The moisture content of the commodity plays an important role in insect infestation during storage. Drying to safe moisture levels before storage is known to prevent the activity of various living organisms, such as storage pests. However, drying to low levels of moisture may not be economical for farmers, as they may not have access to devices to accurately check product moisture. In this regard, we wanted to demonstrate the efficacy of triple-layer hermetic storage bags in preventing the damage caused by C. serratus when the groundnuts are stored at intermediate (10%) and high (14%) levels of moisture compared to traditionally used bags such as polypropylene bags and jute bags. Groundnut pods at 10% moisture content and 14% moisture content were separately inoculated with adult bruchids and a toxigenic strain of Aspergillus flavus fungal inoculum before storing them for 6 months. Results from groundnut samples taken at two-month intervals indicated that groundnut pods stored in triple-layer hermetic bags were completely free from infestation by C. serratus by recording a zero number of eggs laid, number of pupae, adult emergence, percentage of loss, and percentage of damage up to 6 months of storage, by creating low oxygen (hypoxia) and high carbon dioxide (hypercarbia) conditions. Results also indicate no loss of pod weight stored in triple-layer bags, but a slight reduction in germination percentage was recorded due to a slight increase in fungal activity, but the reduction was significantly less in triple-layer plastic bags compared to other bag types. Similarly, biochemical constituents such as oil and protein content were slightly reduced in triple-layer plastic bags when pods were stored at a 10% moisture level, but a higher reduction was observed at a 14% moisture level. However, the reduction was very high and significant in other bag types at both 10 and 14% moisture levels

    Crocins with high levels of sugar conjugation contribute to the yellow colours of early-spring flowering

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    Crocus sativus is the source of saffron spice, the processed stigma which accumulates glucosylated apocarotenoids known as crocins. Crocins are found in the stigmas of other Crocuses, determining the colourations observed from pale yellow to dark red. By contrast, tepals in Crocus species display a wider diversity of colours which range from purple, blue, yellow to white. In this study, we investigated whether the contribution of crocins to colour extends from stigmas to the tepals of yellow Crocus species. Tepals from seven species were analysed by UPLC-PDA and ESI-Q-TOF-MS/MS revealing for the first time the presence of highly glucosylated crocins in this tissue. beta-carotene was found to be the precursor of these crocins and some of them were found to contain rhamnose, never before reported. When crocin profiles from tepals were compared with those from stigmas, clear differences were found, including the presence of new apocarotenoids in stigmas. Furthermore, each species showed a characteristic profile which was not correlated with the phylogenetic relationship among species. While gene expression analysis in tepals of genes involved in carotenoid metabolism showed that phytoene synthase was a key enzyme in apocarotenoid biosynthesis in tepals. Expression of a crocetin glucosyltransferase, previously identified in saffron, was detected in all the samples. The presence of crocins in tepals is compatible with the role of chromophores to attract pollinators. The identification of tepals as new sources of crocins is of special interest given their wide range of applications in medicine, cosmetics and colouring industries.The laboratory is supported by the Spanish Ministerio de Ciencia e Innovacion (BIO2009-07803) and participates in the IBERCAROT network (112RT0445). Dr. Ahrazem was funded by FPCYTA through the INCRECYT Programme. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Rubio-Moraga, A.; Ahrazem, O.; Rambla Nebot, JL.; Granell Richart, A.; GĂłmez GĂłmez, L. (2013). Crocins with high levels of sugar conjugation contribute to the yellow colours of early-spring flowering. PLoS ONE. 8(9):71946-71946. https://doi.org/10.1371/journal.pone.0071946S719467194689Auldridge, M. E., McCarty, D. R., & Klee, H. J. (2006). Plant carotenoid cleavage oxygenases and their apocarotenoid products. Current Opinion in Plant Biology, 9(3), 315-321. doi:10.1016/j.pbi.2006.03.005AKIYAMA, K. (2007). Chemical Identification and Functional Analysis of Apocarotenoids Involved in the Development of Arbuscular Mycorrhizal Symbiosis. Bioscience, Biotechnology, and Biochemistry, 71(6), 1405-1414. doi:10.1271/bbb.70023Lendzemo, V. W., Kuyper, T. W., Matusova, R., Bouwmeester, H. J., & Ast, A. V. (2007). Colonization by Arbuscular Mycorrhizal Fungi of Sorghum Leads to Reduced Germination and Subsequent Attachment and Emergence ofStriga hermonthica. Plant Signaling & Behavior, 2(1), 58-62. doi:10.4161/psb.2.1.3884Gomez-Roldan, V., Fermas, S., Brewer, P. B., Puech-PagĂšs, V., Dun, E. A., Pillot, J.-P., 
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    A study of clinical and pathological correlation in cases of thrombotic microangiopathy

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    Background : Thrombotic Microangiopathy (TMA) is defined as a lesion comprising vessel wall thickening (mainly arterioles and capillaries), intra luminal thrombosis and partial or complete obstruction of the vessel lumina.Thrombotic Microangiopathies are a group of conditions characterized by micro vascular thrombosis leading to thrombocytopenia, hemolytic anemia and red cell fragmentation.Objective : Retrospective analysis of clinical and pathological features of patients with thrombotic microangiopthy.Methods :Twenty eight patients who were diagnosed histopathologically as cases of thrombotic microangiopthy in Gandhi Hospital over a period of 5 years from August 2005 to July 2010 were included in this study. Renal profile including ultrasound study were carried out in all cases and repeated every month. Results: Of the total twenty eight patients 15 were males (54%), 13 were females (46%). Aetiology consists of diarrhea associated HUS (36%), idiopathic (18%), post transplant HUS (14%), post partum HUS (14%), malignant hypertension (11%) and SLE with APLA (7%) leading to thrombotic microangiopthy. Clinical presentations were oligoanuria in 89%, anasarca in 85%, hypertension in 85%, jaundice in 39%, diarrhea in 36%, bleeding diathesis in 25%, seizures in 18% and gross hematuria in 7%. Anemia and thrombocytopenia were universal features. Conclusion: This study shows glomerular changes were predominant in children with thrombotic microangiopthy. Adults with thrombotic microangiopthy have glomerular as well as vascular changes. An attempt has been made to study renal survival and Dialysis dependency in the patients studied by having follow up of one year

    Discrimination between synthetically administered and endogenous thiouracil based on monitoring of urine, muscle, and thyroid tissue : an in vivo study in young and adult bovines

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    Thiouracil (TU), synthesized for its thyroid-regulating capacities and alternatively misused in livestock for its weight-gaining effects, is acknowledged to have an endogenous origin. Discrimination between low-level abuse and endogenous occurrence is challenging and unexplored in an experimental setting. Therefore, cows (n = 16) and calves (n = 18) were subjected to a rapeseed-supplemented diet or treated with synthetic Till. Significant higher urinary TU levels were recorded after TU administration (<CC alpha 15 642 mu g L-1) compared to rapeseed supplementation (<CC alpha, 5.8 mu g L-1), however, with overlapping values. TU was not detected in the edible meat; however, concentrations between the CC alpha, and 10 mu g kg(-1) were noted in thyroid tissue of calves and cows following rapeseed supplementation. The latter concentrations were significantly higher in thyroid tissue of calves (22.9-41.8 mu g kg(-1)) and cows (16.9-36.7 mu g kg (-1)) after synthetic TU administration. These results strongly point toward thyroid analysis as a discriminatory tool.

    Estimation of Autoignition Propensity in Aeroderivative Gas Turbine Premixers Using Incompletely Stirred Reactor Network Modeling

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    Abstract The study of autoignition propensity in premixers for gas turbines is critical for their safe operation and design. Although premixers can be analyzed using reacting computational fluid dynamics (CFD) coupled with detailed autoignition chemical kinetics, it is essential to also develop methods with lower computational cost to be able to explore more geometries and operating conditions during the design process. This paper presents such an approach based on incompletely stirred reactor network (ISRN) modeling. This method uses a CFD solution of a nonreacting flow and subsequently estimates the spatial evolution of reacting scalars such as autoignition precursors and temperature conditioned on the mixture fraction, which is used to quantify autoignition propensity. The approach is intended as a “postprocessing” step, enabling the use of very complex chemical mechanisms and the study of many operating conditions. For a representative premixer of an aeroderivative gas turbine, results show that autoignition propensity can be reproduced with ISRN at highly reactive operating conditions featuring multi-stage autoignition of a dual fuel mixture. The ISRN computations are consequently analyzed to explore the evolution of reacting scalars and propose some autoignition metrics that combine mixing and chemical reaction to assist the design of premixers.Siemens Energ
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