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Performance assessments of jatropha, palm oil and soya bean based biodiesel were carried out to investigate their potential use as conventional substitute for kerosene for domestic purposes in rural- Ghana. The assessments were done by comparing some of the combustion characteristics of blends of the biodiesel with kerosene. The blends were categorised as B100 (100% biodiesel), B80 (80% biodiesel and 20% kerosene), B60 (60% biodiesel and 40% kerosene), B40 (40% biodiesel and 60% kerosene), B20 (20% biodiesel and 80% kerosene) and B0 (pure kerosene). The results showed that the calorific values of the B100s were less than that of the B0 and decreasing in the order of jatropha, soya bean and palm oil. The wick wastage results for both the B100s and B0, revealed higher rates in the WTL than the BB even though the BB recorded low fuel consumption rates than the WTL for both B100s and B0. Similarly, the luminous intensity test with the B100s showed low values in WTL than the BB in a decreasing order of jatropha, soya bean and palm oil. However, B0 recorded higher luminous intensity values that were quite comparable in both WTL and BB. [ABSTRACT FROM AUTHOR]

The Pra river catchment in Ghana is adversely affected by perennial flooding from high-intensity rainfall events. To aid in flood management at the catchment, the Gumbel extreme value distribution has been used to estimate the return periods of maxima rainfall, flood, and consecutive dry and wet days (CDD and CWD) for a period of 5 to 100 years. The results revealed an expected increase in maxima rainfall, CDD and CWD. Maxima rainfall favours the south of the catchment while the CDD decreases northward. Furthermore, an increase in the magnitude of CWD observed at the centre of the catchment had a maximum of approximately 30 days for the 100 year return period, while lower flood volumes had a higher recurrence of 50% to 100% for 1 to 2 year return periods. The inclusion of a projected increase in anthropogenic activities and climate factors at the catchment will slightly affect the magnitude of these variables for the various return periods. Nonetheless, the findings in this study will be of essential input to policy implementation of the Integrated Water Resource Management Plan for river catchments in Ghana, West Africa., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Neutrophils are key cells from the innate immune system that destroy invading bacteria or viruses, thanks mainly to the non-mitochondrial reactive oxygen species (ROS) generated by the enzyme NADPH oxidase. Our aim was to study the response of neutrophils to situations of oxidative stress with emphasis on the impact on the NADPH oxidase complex. To mimic oxidative stress, we used gamma irradiation that generated ROS (OH • , O 2 •- and H 2 O 2 ) in a quantitative controlled manner. We showed that, although irradiation induces shorter half-lives of neutrophil (reduced by at least a factor of 2), it triggers a pre-activation of surviving neutrophils. This is detectable by the production of a small but significant amount of superoxide anions, proportional to the dose (about 3 times that of sham). Investigations at the molecular level showed that this ROS increase was generated by the NADPH oxidase enzyme after neutrophils irradiation. The NADPH oxidase complex undergoes an incomplete assembly which includes p47 phox and p67 phox but excludes the G-protein Rac. Importantly, this irradiation-induced pre-activation is capable of considerably improving neutrophil reactivity. Indeed, we have observed that this leads to an increase in the production of ROS and the capacity of phagocytosis, leading to the conclusion that radiation induced ROS clearly behave as neutrophil primers., (Copyright © 2020 Elsevier Inc. All rights reserved.)