Corporate social performance and firm debt levels: Impacts of the covid-19 pandemic and institutional environments.

This paper examines the relation between corporate social performance (CSP) and firm debt levels and explores the channels between them by focusing on the ongoing health crisis, the COVID-19 pandemic. We use a large sample of public firms from 31 countries between 2002 and 2020. Employing pooled ordinary least squared and firm fixed effects models, after controlling for endogeneity and sample selection bias, we find that during the pre-COVID economic condition, CSP has a significantly positive impact on firm debt levels by reducing financial constraints and enhancing stakeholder engagement. However, during the outbreak, CSP becomes costlier and reveals more managerial agency problems for firms that make such associations attenuated. Furthermore, our evidence suggests that in countries with better institutional environments, the CSP-firm debt levels relation is less pronounced. These results have several implications in terms of investment and capital structure decisions.

Polyhydroxyalkanoates production from carbohydrates by a genetic recombinant Aeromonas sp.

AIMS: To develop an Aeromonas strain able to utilize inexpensive carbon sources such as starch for the synthesis of polyhydroxyalkanoates (PHA). METHODS AND RESULTS: A recombinant Aeromonas sp. (strain KC007-1) was constructed by introducing the PHB synthesis genes (phaCAB) into the bacterium. Strain KC001-R1 can not only use carbohydrate (including starch) for growth but also accumulate significant amounts of polyhydroxybutyrate (PHB) in the cells. CONCLUSIONS: One of the present focuses on PHA production has been on lowering the production costs. Starch is an example of an inexpensive carbohydrate for use in industrial production of PHA. We have demonstrated that by introducing the phaCAB operon into Aeromonas sp. allowed the bacterium able to accumulated PHB using this substrate. SIGNIFICANCE AND IMPACT OF THE STUDY: Aeromonas spp. are able to synthesize PHA using fatty acids as carbon source. Although good robust growth results with use of starch as sole carbon source for Aeromonas, PHA synthesis does not occur. Strain KC007-R1 showed the ability to accumulate PHA in relative high amount with both carbohydrates and fatty acids as carbon source, and can be cultivated to a significant amount of cell mass and hence is a potential strain for further development for industrial applications.

Environmental and Occupational Health Impact of Bauxite Mining in Malaysia: A Review

In the perspective of recent bauxite mining in Malaysia, this review aims to identify the potential environmental and health impacts on miners and surrounding communities. The environmental issues of bauxite mining include, air, water and soil pollution due to bauxite dust; leaching of bauxite into water sources resulting in reduced soil fertility as well as affecting agricultural food products and aquatic life. Bauxite occupational exposure affects the health of miners, and has negative consequences on the health of surrounding communities, such as increased respiratory symptoms, contamination of drinking water, other potential health risks from ingestion of bauxite and heavy metals, including noise-induced hearing loss and mental stress. This review discusses the processes of bauxite mining, its constituents and residual trace elements, and their impact on the environment and health of exposed workers and communities. It also explores the Malaysian legal requirements and standards of occupational exposure to bauxite.

Species composition and pyrethroid susceptibility status of Anopheles mosquitoes from two different locations in Malaysia

A 14-months survey was carried out to identify the species composition of Anopheles mosquitoes from Kampung Bongor, Grik, Perak. Adding to that, a preliminary one month mosquito population screening was done at Kampung Tepin, Serian, Sarawak. Consequently, the insecticide susceptibility status of a pyrethroid was tested against two selected species of Anopheles collected from these two locations in Malaysia. A total of 4,497 Anopheles from 11 species were identified from collections in Kampung Bongor, whereas 2,654 An. letifer were collected from Kampung Tepin. The An. maculatus of Kampung Bongor and An. letifer of Kampung Tepin were then selected and tested using WHO standard diagnostic test kits and impregnated papers with 0.75% permethrin. The response values of KT50 and KT95 for An. maculatus were recorded at 28.09 minutes and 62.98 minutes respectively. Anopheles letifer recorded much slower response values of KT50 and KT95, which was at 35.09 minutes and 73.03 minutes respectively. Both An. maculatus and An. letifer showed 100% mortality after 24 hours holding period. The results indicate that both species were still susceptible to the tested pyrethroid. For effective vector control and resistance management, accurate and periodic insecticide resistance monitoring should be undertaken especially in rural areas with agricultural usage of insecticides.