94 research outputs found

    Cycloadditions in mixed aqueous solvents: the role of the water concentration

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    We examined the kinetics of a series of cycloaddition reactions in mixtures of water with methanol, acetonitrile and poly(ethylene glycol) (MW 1000). The reactions include the Diels–Alder (DA) reaction between cyclopentadiene and N-n-butylmaleimide or acridizinium bromide, the retro-Diels-Alder (RDA) reaction of 1,4,4a,9a-tetrahydro-4a-methyl-(1α,4α,4aα,9aα)-1,4-methaneanthracene-9,10-dione and the 1,3-dipolar cycloaddition of benzonitrile oxide with N-n-butylmaleimide. Plots of logk vs the molar concentration or volume fraction of water are approximately linear, but with a characteristic break around 40 M water. This break, absent for the RDA reaction, is ascribed to hydrophobic effects. Comparison with aqueous mixtures of the more hydrophobic 1-propanol shows that these mixtures induce qualitatively similar effects on the rate, but that preferential solvation effects cause the mixtures of 1-propanol to exhibit a more complex behavior of logk on composition. The results are analyzed using the Abraham–Kamlett–Taft model. The solvent effects in aqueous mixtures are not satisfactorily described by this model. For some cycloadditions, small maxima in rate are observed in highly aqueous mixtures of alcohols. The origin of these maxima and the aforementioned breaks is most likely the same.

    COP27 Climate Change Conference: Urgent action needed for Africa and the world

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    Wealthy nations must step up support for Africa and vulnerable countries in addressing past, present and future impacts of climate change.The 2022 report of the Intergovernmental Panel on Climate Change (IPCC) paints a dark picture of the future of life on earth, characterised by ecosystem collapse, species extinction, and climate hazards such as heatwaves and floods. These are all linked to physical and mental health problems, with direct and indirect consequences of increased morbidity and mortality. To avoid these catastrophic health effects across all regions of the globe, there is broad agreement—as 231 health journals argued together in 2021—that the rise in global temperature must be limited to less than 1.5oC compared with pre-industrial levels. While the Paris Agreement of 2015 outlines a global action framework that incorporates providing climate finance to developing countries, this support has yet to materialise. COP27 is the fifth Conference of the Parties (COP) to be organised in Africa since its inception in 1995. Ahead of this meeting, we—as health journal editors from across the continent—call for urgent action to ensure it is the COP that finally delivers climate justice for Africa and vulnerable countries. This is essential not just for the health of those countries, but for the health of the whole world

    Women’s overall satisfaction with health facility delivery services in Ghana: a mixed-methods study

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    Background: Skilled birth delivery has increased up to nearly 74% in Ghana, but its quality has been questioned over the years. As understanding women's satisfaction could be important to improving service quality, this study aimed to determine what factors were associated with women's overall satisfaction with delivery services quantitatively and qualitatively in rural Ghanaian health facilities. Results: This cross-sectional, mixed methods study used an explanatory sequential design across three Ghana Health Service research areas in 2013. Participants were women who had delivered in the preceding 2 years. Two-stage random sampling was used to recruit women for the quantitative survey. Relationships between women's socio-demographic characteristics and their overall satisfaction with health facility delivery services were examined using univariate and multiple logistic regression analyses. For qualitative analyses, women who completed the quantitative survey were purposively selected to participate in focus group discussions. Data from the focus group discussions were analyzed based on predefined and emerging themes. Overall, 1130 women were included in the quantitative analyses and 136 women participated in 15 focus group discussions. Women's mean age was 29 years. Nearly all women (94%) were satisfied with the overall services received during delivery. Women with middle level/junior high school education [adjusted odds ratio (AOR) = 0.50, 95% confidence interval (CI) = (0.26-0.98)] were less likely to be satisfied with overall delivery services compared to women with no education. Qualitatively, women were not satisfied with the unconventional demands, negative attitude, and unavailability of healthcare workers, as well as the long wait time. Conclusions: Although most women were satisfied with the overall service they received during delivery, they were not satisfied with specific aspects of the health services; therefore, higher quality service delivery is necessary to improve women's satisfaction. Additional sensitivity training and a reduction in work hours may also improve the experience of clients

    Determinants of attending antenatal care at least four times in rural Ghana: analysis of a cross-sectional survey.

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    BACKGROUND: Improving maternal health is a global challenge. In Ghana, maternal morbidity and mortality rates remain high, particularly in rural areas. Antenatal care (ANC) attendance is known to improve maternal health. However, few studies have updated current knowledge regarding determinants of ANC attendance. OBJECTIVE: This study examined factors associated with ANC attendance in predominantly rural Ghana. METHODS: We conducted a cross-sectional study at three sites (i.e. Navrongo, Kintampo, and Dodowa) in Ghana between August and September 2013. We selected 1500 women who had delivered within the two years preceding the survey (500 from each site) using two-stage random sampling. Data concerning 1497 women's sociodemographic characteristics and antenatal care attendance were collected and analyzed, and factors associated with attending ANC at least four times were identified using logistic regression analysis. RESULTS: Of the 1497 participants, 86% reported attending ANC at least four times, which was positively associated with possession of national health insurance (AOR 1.64, 95% CI: 1.14-2.38) and having a partner with a high educational level (AOR 1.64, 95% CI: 1.02-2.64) and negatively associated with being single (AOR 0.39, 95% CI: 0.22-0.69) and cohabiting (AOR 0.57, 95% CI: 0.34-0.97). In site-specific analyses, factors associated with ANC attendance included marital status in Navrongo; marital status, possession of national health insurance, partners' educational level, and wealth in Kintampo; and preferred pregnancy timing in Dodowa. In the youngest, least educated, and poorest women and women whose partners were uneducated, those with health insurance were more likely to report at least four ANC attendances relative to those who did not have insurance. CONCLUSIONS: Ghanaian women with low socioeconomic status were less likely to report at least four ANC attendances during pregnancy if they did not possess health insurance. The national health insurance scheme should include a higher number of deprived women in predominantly rural communities

    Multi-Country Evaluation of Safety of Dihydroartemisinin/Piperaquine Post-Licensure in African Public Hospitals with Electrocardiograms.

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    The antimalarial drug piperaquine is associated with delayed ventricular depolarization, causing prolonged QT interval (time taken for ventricular de-polarisation and re-polarisation). There is a lack of safety data regarding dihydroartemisinin/piperaquine (DHA/PPQ) for the treatment of uncomplicated malaria, which has limited its use. We created a platform where electrocardiograms (ECG) were performed in public hospitals for the safety assessment of DHA/PPQ, at baseline before the use of dihydroartemisinin/piperaquine (Eurartesim®), and on day 3 (before and after administration of the final dose) and day 7 post-administration. Laboratory analyses included haematology and clinical chemistry. The main objective of the ECG assessment in this study was to evaluate the effect of administration of DHA/PPQ on QTc intervals and the association of QTc intervals with changes in blood biochemistry, full and differential blood count over time after the DHA/PPQ administration. A total of 1315 patients gave consent and were enrolled of which 1147 (87%) had complete information for analyses. Of the enrolled patients 488 (42%), 323 (28%), 213 (19%) and 123 (11%) were from Ghana, Burkina Faso, Tanzania and Mozambique, respectively. Median (lower-upper quartile) age was 8 (5-14) years and a quarter of the patients were children under five years of age (n = 287). Changes in blood biochemistry, full and differential blood count were temporal which remained within clinical thresholds and did not require any intervention. The mean QTcF values were significantly higher than on day 1 when measured on day 3 before and after administration of the treatment as well as on day 7, four days after completion of treatment (12, 22 and 4 higher, p < 0.001). In all age groups the values of QT, QTcF and QTcB were highest on day 3 after drug intake. The mean extreme QTcF prolongation from baseline was lowest on day 3 before drug intake (33 ms, SD = 19) and highest on day 3 after the last dose (60 ms, SD = 31). There were 79 (7%) events of extreme mean QTcF prolongation which were not clinically significant. Nearly a half of them (n = 37) were grade 3 and mainly among males (33/37). Patients in Burkina Faso, Mozambique and Tanzania had significantly lower mean QTcF than patients in Ghana by an average of 3, 4 and 11 ms, respectively. We found no evidence that Eurartesim® administered in therapeutic doses in patients with uncomplicated malaria and no predisposing cardiac conditions in Africa was associated with adverse clinically significant QTc prolongation
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