How do migration decisions and drivers differ against extreme environmental events?

Migration is often understood to be a livelihood strategy to cope with the effects of environmental threats and climate change. Yet, the extent to which migration decisions differ due to the type, severity, and frequency of environmental events has been little explored. This paper employs household surveys in southwestern Bangladesh to explore this research gap. A multinominal regression model is used to simulate reported future migration decisions (200 sample households) in the context of both rapid-onset (i.e. cyclone and flood) and slow-onset (salinity, siltation, and riverbank erosion) environmental phenomena. Results show: i) previous disaster experience and increasing conflict in the community motivate migration in the near future in the context of slow-onset phenomena (salinity); (ii) economic strength and self-efficacy increase non-migration intention in both contexts of sudden and slow-onset events; and (iii) the extent and pattern of these influences on migration differ across demographics, including education, religion, and age. Importantly, this analysis shows that the relationship between migration decisions and the type, severity, and frequency of environmental events is influenced by socioeconomic conditions. Therefore, this research supports future adaptation planning specifically tailored to the type and exposure of extreme environmental events.

Genome-wide analysis and characterization of heat shock transcription factors (Hsfs) in common bean (Phaseolus vulgaris L.)

Heat shock transcription factors (Hsfs) play an essential role as transcriptional regulatory proteins against heat stress by controlling the expression of heat-responsive genes. Common bean is a highly thermosensitive crop, and, therefore, its genome sequence information is segregated, characterized here in terms of heat shock transcription factors and its evolutionary significance. In this study, a complete comprehensive set of 29 non-redundant full-length Hsf genes were identified and characterized from Phaseolus vulgaris L. (PvHsf) genome sequence. Detailed gene information such as chromosomal localization, domain position, motif organization, and exon-intron identification were analyzed. All the 29 PvHsf genes were mapped on 8 out of 11 chromosomes, indicating the gene duplication occurred in the common bean genome. Motif analysis and exon-intron structure were conserved in each group, which showed that the cytoplasmic proteins highly influence the conserved structure of PvHsfs and heat-induced response. The HSF genes were grouped into three classes, i.e., A to C and 14 groups, based on structural features and phylogenetic relationships. Only one pair of paralog sequences suggests that it may be derived from the duplication event during evolution. A comparative genomics study indicated the influence of whole-genome duplication and purifying selection on the common bean genome during development. In silico expression analysis showed the active role of class A and B family during abiotic stress conditions and higher expression in floral organs. The qRT-PCR analysis revealed PvHSFA8 as the master regulator and PvHSFB1A and PvHSFB2A induction during heat exposure in French beans.

In harm's way: Non-migration decisions of people at risk of slow-onset coastal hazards in Bangladesh

Non-migration is an adaptive strategy that has received little attention in environmental migration studies. We explore the leveraging factors of non-migration decisions of communities at risk in coastal Bangladesh, where exposure to both rapid- and slow-onset natural disasters is high. We apply the Protection Motivation Theory (PMT) to empirical data and assess how threat perception and coping appraisal influences migration decisions in farming communities suffering from salinization of cropland. This study consists of data collected through quantitative household surveys (n = 200) and semi-structured interviews from four villages in southwest coastal Bangladesh. Results indicate that most respondents are unwilling to migrate, despite better economic conditions and reduced environmental risk in other locations. Land ownership, social connectedness, and household economic strength are the strongest predictors of non-migration decisions. This study is the first to use the PMT to understand migration-related behaviour and the findings are relevant for policy planning in vulnerable regions where exposure to climate-related risks is high but populations are choosing to remain in place.

A bibliometric review on the drivers of environmental migration

A large body of literature exists arguing that numerous, complex factors result in environmental migration. Thus, in order to understand environmental migration, we must investigate how its drivers are defined, explained and interrelated. This study aims to produce a comprehensive analysis of the literature on the drivers of environmental migration and assess future opportunities for studying 'environmental migration'. We conduct a systematic literature search using the keywords 'environmental migration' and 'drivers' in Scopus and Web of Knowledge, analysing 146 publications. The findings are organised as a bibliometric analysis, including network analysis and evaluation of publication metrics. Results show that the literature on environmental migration drivers constitutes a relatively new, growing field largely developed in the USA. It is rooted in the wider environmental migration literature and strongly associated with the discourse of climate change impacts as driving factors. Typologies of 'migrants' are more prevalent than 'refugees' when referring to actors.

Livelihood challenges of 'double strike' disasters: Evidence from rural communities of southwest coastal Bangladesh during the Covid-19 pandemic and cyclone Amphan

The Covid-19 pandemic has adversely affected livelihoods in the Global South and exacerbated the effects of natural disaster. This study examines the 'double strike' of the Covid-19 lockdown and 'super-cyclone' Amphan on the 12 villages of Dakshin Bedkashi Union, southwest Bangladesh. It employs questionnaire surveys to assess the impact of the compound disaster on rural livelihoods over a period of five months, comparing pre-lockdown, post-lockdown, and post-Amphan phases. The results demonstrate the severe impact of the pandemic on income, occupation, and workdays, and consequently on livelihood resilience leading up to Amphan. Although effects vary moderately by livelihood category, village, and socio-spatial characteristics, overall rates of income reduction (58%) and occupation loss (77%) between the advent of the lockdown and the aftermath of Amphan are high. Thus, livelihood resilience to the double strike is generally poor. The study analyses the predictors of lost working days to illuminate the influences on livelihood resilience throughout the double strike. We conclude that the pandemic has presented novel challenges to this region, complicating vulnerability to more common cyclonic natural hazards. Finding that the degree of livelihood diversification is low in the sample, we recommend implementing diversification policies and strengthening local networks and community trust to better anticipate and combat the complex, varied impacts of double strike scenarios in future.

Key opportunities and challenges for the use of big data in migration research and policy

Migration is one of the defining issues of the 21st century. Better data is required to improve understanding about how and why people are moving, target interventions and support evidence-based migration policy. Big data, defined as large, complex data from diverse sources, is regularly proposed as a solution to help address current gaps in knowledge. The authors participated in a workshop held in London, UK, in July 2019, that brought together experts from the United Nations (UN), humanitarian non-governmental organisations (NGOs), policy and academia to develop a better understanding of how big data could be used for migration research and policy. We identified six key areas regarding the application of big data in migration research and policy: accessing and utilising data; integrating data sources and knowledge; understanding environmental drivers of migration; improving healthcare access for migrant populations; ethical and security concerns around the use of big data; and addressing political narratives. We advocate the need for careful consideration of the challenges faced by the use of big data, as well as increased cross-disciplinary collaborations to advance the use of big data in migration research whilst safeguarding vulnerable migrant communities.

Evaluation of molecular interaction, physicochemical parameters and conserved pattern of SARS-CoV-2 Spike RBD and hACE2: in silico and molecular dynamics approach

OBJECTIVE

Recent pandemic virus SARS-CoV-2 is a global warning for the healthcare system. The spike protein of virus SARS-CoV-2 is significant because of two reasons. Firstly, the spike protein of this virus binds with the human ACE2 (hACE2) receptor. Secondly, it has several antigenic regions that might be targeted for vaccine development. However, the structural analytical data for the spike protein of this virus is not available.

MATERIALS AND METHODS

Here, we performed an analysis to understand the structural two subunits of S glycoprotein (S gp) of SARS-CoV-2. Further, an analysis of secondary structure components and the tertiary structure analysis of RBD was carried out. We also performed molecular interaction analysis between S gp of this virus and hACE2 as well as between SARS-CoV S gp and hACE2 to compare the binding properties of these two viruses.

RESULTS

We noted that the molecular interaction of SARS-CoV-2 S gp and hACE2 form eleven hydrogen bonds, while the molecular interaction of SARS-CoV S gp and hACE2 receptor form seven hydrogen bonds, indicating that the molecular interaction of SARS-CoV-2 S gp and hACE2 receptor is more stable than SARS-CoV S gp and hACE2 receptor. The pairwise sequence alignment of S gp SARS-CoV and SARS-CoV-2 shows several conserved residues of these two proteins. Besides, conserved pattern analysis of SARS-CoV-2 S gp and hACE2 revealed the presence of several highly conserved regions for these two proteins. The molecular dynamics simulation shows a stable interplay between SARS-CoV-2 S gp with the hACE2 receptor.

CONCLUSIONS

The present study might help determine the SARS-CoV-2 virus entrance mechanism into the human cell. Moreover, the understanding of the conserved regions may help in the process of therapeutic development from the infection of the deadly virus.

Challenges of Testing COVID-19 Cases in Bangladesh

Keeping the dynamic nature of Coronaviruses (COVID-19) pandemic in mind, we have opted to explore the importance of the decentralization of COVID-19 testing centers across the country of Bangladesh in order to combat the pandemic. In doing so, we considered quantitative, qualitative, and geographic information systems (GIS) datasets to identify the location of existing COVID-19 testing centers. Moreover, we attempted to collect data from the existing centers in order to demonstrate testing times at the divisional level of the country. Results show that the number of testing centers is not enough to cater to the vast population of the country. Additionally, we found that the number of days it takes to receive the results from the COVID-19 testing centers is not optimal at divisional cities, let alone the remote rural areas. Finally, we propose a set of recommendations in order to enhance the existing system to assist more people under a testing range of COVID-19 viruses at the local level.

Synthesis and Application of Nano structured Bi layer YSZ LZ Thermal Barrier Coating

Present work is on synthesis of high purity Nano-structured TBC materials, Lanthanum Zirconate and YSZ. They were prepared via wet chemical routes, starting from the indigenous source minerals such as zircon and monazite available in the beach sand. This is first time that the results of TBC materials synthesis from these base minerals, their purification and a high end application being presented comprehensively. Their characterisation and thermal barrier application on aeroengine components have been presented. The total oxide impurities being critical to the life of the coating, could be controlled within 0.03 per cent by weight. On comparison with other powders it was found that the indigenously synthesised YSZ powder had practically 100 per cent tetragonal prime phase and no monoclinic phase; whereas others had significant amounts of monoclinic phases present in them. Both YSZ and LZ powders were sinter agglomerated at 850 °C to preclude the possibility of any contamination and sieved. APS process was used to realise nano-structured bi-layer coating on the exhaust nozzle parts of an aeroengine. The components were subjected to rapid thermal transients during long accelerated endurance testing, equivalent to 1000 h of engine operations. The coatings also withstood the gas erosion of supersonic combustion products, vibratory loads of 4 g and more than 30000 nozzle actuations similar to aircraft maneuver. The paper also presents a brief review of implications of a nano-structured thermal barrier coating and certain nuances of chemical synthesis which forms the backbone of the strategies for durable coatings.

Modulation of the CO2 fixation in dinickel azacryptands

Different linker molecules within the dinickel azacryptand moiety show strong influence towards their CO₂ coordination behaviour.

New amidinate complexes of indium(iii): promising CVD precursors for transparent and conductive In2O3 thin films

Heteroleptic and homoleptic In(iii)-amidinate complexes as promising CVD precursors for In₂O₃ thin films.

Cyclone shelters and their locational suitability: an empirical analysis from coastal Bangladesh

Bangladesh is one of the poorest and the most disaster-prone countries in Asia; it is important, therefore, to know how its disaster reduction strategies are organised and planned. Cyclone shelters comprise a widely acceptable form of infrastructural support for disaster management in Bangladesh. This paper attempts to analyse empirically their use during cyclones in a sample study area along the southwest coastal belt of the country. It shows how the location of a cyclone shelter can determine the social power structure in coastal Bangladesh. The results reveal that the establishment of cyclone shelters in the studied communities is determined by neither a right-based nor a demand-based planning approach; rather, their creation is dependent on the socio-political affluence of local-level decision-makers. The paper goes on to demonstrate that socially vulnerable households (defined, for example, by income or housing conditions) are afforded disproportionately less access to cyclone shelters as compared to less socially vulnerable households.

CO2-helium and CO2-neon mixtures at high pressures

The properties of mixtures of carbon dioxide with helium or neon have been investigated as a function of CO(2) concentration and pressure up to 30 GPa at room temperature. The binary phase diagrams of these mixtures are determined over the full range of CO(2) concentrations using visual observations and Raman scattering measurements. Both diagrams are of eutectic type, with a fluid-fluid miscibility gap for CO(2) concentrations in the range [5, 75] mol. % for He and [8, 55] mol. % for Ne, and a complete separation between the two components in the solid phase. The absence of alloys or stoichiometric compounds for these two binary systems is consistent with the Hume-Rothery rules of hard sphere mixtures. The Raman spectra and x-ray diffraction patterns of solid CO(2) embedded in He or Ne for various initial concentrations have been measured up to 30 GPa and 12 GPa, respectively. The frequencies of the Raman modes and the volume of solid phase I are identical, within error bars, to those reported for 100% CO(2) samples, thus confirming the total immiscibility of CO(2) with He and Ne in the solid phase. These results demonstrate the possibility to perform high-pressure experiments on solid CO(2) under (quasi-)hydrostatic conditions using He or Ne as pressure transmitting medium.

Role of azithromycin against clinical isolates of family enterobacteriaceae: A comparison of its minimum inhibitory concentration by three different methods

PURPOSE

To determine the effect of azithromycin, a new azalide antibiotic, on clinical isolates of the family Enterobacteriaceae and to determine and compare its minimum inhibitory concentration (MIC) by disk diffusion, agar dilution and E-test methods.

MATERIALS AND METHODS

One hundred fifty-nine bacterial strains belonging to the family Enterobacteriaceae, isolated from different clinical samples, were tested for their susceptibility to azithromycin by disk diffusion, agar dilution and E-test methods. The MIC values were analysed and the percentages of agreement between the different methods were mentioned.

RESULTS

Of the 159 isolates of the family Enterobacteriaceae, 60.37% were E. coli followed by Klebsiella species 28.3%, Salmonella and Shigella species 3.77% and Enterobacter and Citrobacter species 1.88% each. Maximum isolates were obtained from urine 117/159 (73.58%). Azithromycin was found to be more active against Salmonella and Shigella species, showing 100% sensitivity the by E-test and 83.33% by the disk diffusion methods. In the agar dilution method, 83.33% of Salmonella and 66.66% of Shigella species were sensitive to azithromycin. The overall agreement between disk diffusion and agar dilution method was 96.8%, between agar dilution and E-test was 88% and between disk diffusion and E-test was 91.2%.

CONCLUSION

Azithromycin may become an important addition to our antimicrobial strategies, especially for the treatment of bacterial diarrhoea and infections caused by Salmonella typhi.

Seroprevalence of anti HCV antibody in and around Cuttack, Orissa

One hundred ninety (190) serum samples and 52 control samples consisting of high risk individuals were screened for anti HCV antibody by 3rd generation ELISA test. The prevalence rate was found to be 1.57% in total but it was 2.12% in healthy voluntary blood donors. All were males between the age group of 21 to 40 years. All the control samples were found to be seronegative for anti HCV ab.

Cleogynol, a novel dammarane triterpenoid from Cleome gynandra

Chemical examination of Cleome gynandra (whole plant excluding seeds) led to the isolation and identification of a novel (20S, 24S)-epoxy-19,25-dihydroxydammarane-3-one hemiketal (1). The structure of the new compound, designated cleogynol, was determined using spectral and chemical methods.

Binding of alpha-bungarotoxin and cholinergic ligands to acetylcholine receptors in the membrane of skeletal muscle

A membrane fraction enriched in acetylcholine receptors was prepared from denervated cat leg muscles. 97% of the alpha-bungarotoxin-binding sites in the dispersed membranes are sensitive to nicotinic cholinergic ligands. In intact msucle, 90% are. A filtration assay of the binding to the membranes of tritiated alpha-bungarotoxin, as retarded by these ligands, provides a convenient system for the determination of affinities of ligands for the muscle receptor in its membrane-bound state. Affinities were found thus for 6 nicotinic ligands. An allosteric system, rather than desensitisation, may explain the high affinities observed for certain ligands.