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Using six HighResMIP multi-ensemble GCMs (both the atmosphere-only and coupled versions) at 25 km resolution, the Tropical Cyclone (TC) activity over the Bay of Bengal (BoB) is examined in the present (1950–2014) climate. We use the Genesis Potential Index (GPI) to study the large-scale environmental conditions associated with the TC frequency in the models. Although the models struggle to reproduce the observed frequency and intensity of TCs, most models can capture the bimodal characteristics of the seasonal cycle of cyclones over the BoB (with fewer TCs during the pre-monsoon [April–May] than the post-monsoon [October–November] season). We find that GPI can capture the seasonal variation of the TC frequency over the BoB in both the observations and models. After calibrating the maximum sustained windspeeds in the models with IBTrACS, we find that like the observations the proportion of strong cyclones is also higher in the pre-monsoon than the post-monsoon. However, the inter-seasonal contrast of the proportion of strong cyclones between the pre-monsoon and post-monsoon seasons is reduced in almost all the models compared to the observations. The windshear term in GPI contributes the most to the model biases in all models during the post-monsoon season. This bias is caused by weakening of upper-level (200 hPa) easterlies in analysed models. During the pre-monsoon season, the environmental term in GPI dominating the model biases varies from model to model. When comparing the atmosphere-only and coupled versions of the models, a reduction of 0.5 °C in the sea surface temperature (SST) and a lowering of TC frequency occur in almost all the coupled models compared to their atmosphere-only counterparts.

Present study aimed to explore the differences of marital adjustment among educated women in Bangladesh, especially career or dual career married women and non-career or housewives. The study has focused on both qualitative and quantitative approach or mixed method to address the aforesaid issue. Field survey and face to face interview technique was used for data collection. A sample of fifty educated women (twenty-five career and twenty-five non-career women) was selected based on purposive sampling technique and a detailed interview schedule was constructed in this regard. This study revealed that higher educational qualification of husband and wife, increased marital cohesions and harmonies, dissolution and duration of marriage are very important for marital adjustment. Marital adjustment is an important area of research as it promotes emotional stability, intellectual efficiency, and social effectiveness. Int. J. Soc. Sc. Manage. Vol. 8, Issue-2: 372-379

This study describes the development and validation of a simple, specific, accurate, and precise method for quantitative determination of Esomeprazole in human serum using Pantoprazole as internal standard (IS). After the addition of internal standard, Esomeprazole from serum samples was extracted simply by protein precipitation method followed by centrifugation and the supernatants were directly injected into the high performance liquid chromatography (HPLC). The chromatographic separation of the compounds was obtained on Hitachi Lachrom C8 column (5 µm, 250 × 4.6 mm) with a mobile phase consisting of 5 mM potassium dihydrogen phosphate pH 7.4 and acetonitrile in a ratio of 70:30 with UV detection at 302 nm with a flow rate of 1 mL/min. The method was sensitive and specific, and validated over a concentration range of 0.06–6.0 µg/mL. The limit of detection (LOD) and lower limit of quantification (LOQ) was 0.03 µg/mL and 0.06 µg/mL, respectively. The precision and accuracy expressed as relative standard deviation were less than 15%. The average recovery of Esomeprazole from serum was 97.08%.

Present work describes the isolation and morphological identification of endophytic fungi from Phyllanthus niruri L. including their chemical and bioactivity screening. Two isolated and purified endophytic fungi with the internal strain numbers PNRE and PNLE were taxonomically identified as Colletotrichum sp. and Fusarium sp., respectively. Preliminary chemical screening of the fungal extracts through thin layer chromatography (TLC) revealed the presence of various components. PNLE showed significant antifungal activity against the fungi Aspergillus niger (24 mm) and Aspergillus flavus (20 mm). Extracts of PNRE and PNLE gave significant cytotoxic activity with LC50 values of 1.08 μg mL-1 and 1.05 μg mL-1, respectively in the brine shrimp lethality bioassay. PNRE extract showed mild scavenging of DPPH with IC50 value of 96.06 μg mL-1 during antioxidant activity screening. Crystal formation was observed in the crude PNRE fungal extract which was purified using methanol/dichloromethane (0-20%) to obtain pure white crystal and the structure was elucidated by NMR (1H NMR and 13C NMR) spectroscopic analysis to be confirmed as ergosterol. Since isolated fungi showed promising antifungal and cytotoxic activities, the crude extract of endophytic fungi of P. niruri could be considered as a promising source for isolation of potential bioactive compounds. Bangladesh J. Sci. Ind. Res.55(4), 311-318, 2020

Endophytic fungi are a group of fungi that reside in the living plant without causing any disease symptoms. It shows symbiotic/mutualistic characteristics with host plants. Endophytic fungi may increase the host defense system against various pathogenic microorganisms and may encompass secondary metabolites of respective host plants. Isolation of endophytic fungi and its metabolites from Justicia gendarussa plant grown in Bangladesh is a recent and new approach. A total of seven endophytic fungi were isolated and purified from the leaf and bark part of the plant. All of the isolated endophytic fungi were identified up to genus level on the basis of macroscopic and microscopic characteristics and up to species level on the basis of molecular characteristics as Colletotrichum gloeosporioides, Diaporthe pseudomangiferae, Pseudopestalotiopsis camelliae-sinensis, Colletotrichum gloeosporioides, Fusarium solani, Colletotrichum tropicale and Colletotrichum siamense. Preliminary chemical screening of the fungal extracts by thin-layer chromatographic technique revealed the presence of various compounds such as flavonoids, anthraquinones, couramins, isocoumarins etc. Fungal strain Pseudopestalotiopsis camelliae-sinensis exhibited significant antiradical activity through DPPH scavenging method and moderate antimicrobial activity against a wide range of human pathogenic microbes. Using brine shrimp lethality bioassay, all the isolates showed strong cytotoxic activity, therefore suggested that all the extracts may have bioactive metabolites. Overall, these findings indicate that Justicia gendarussa and its associated endophytic fungi could be an important source for exploring potentially bioactive compounds or leads for the new drug candidates.

Investigation of meteorological conditions favorable for formation of pre-monsoon thunderstorm over Bangladesh has been conducted by simulating a selected thunderstorm case using ARW dynamic core of WRF model (WRF-ARW). A multi-cell thunderstorm formed on 30-03-2018 over the northwestern tip of Bangladesh and adjacent territories of India and moved south-southeast wards with its highest development at 09:30 UTC was selected for this study. The chosen case of thunderstorm has 3 distinct cells of which 2 cells have the width of over 100 km each and the third one located in the eastern Bangladesh and had the width of 50 km. A WRF ARW model has been applied to examine the atmospheic characteristics favorabe for genesis of selected case run in a double nested domain of resolution of 9x9 km2 in the outer domain and 3 3 km2in the inner domain. The analysis of the geopotential height field of 925 hPa level generated by WRF model at different hours of 31 March 2018 clearly indicates favourable condition with pockets of micro lows and their progression towards central to southeastern Bangladesh. The strong winds blowing from Bay of Bengal along an anticyclone over the Bay brings sufficient moisture to the north. The southerly winds meet the easterly and also westerly winds providing strong low level convergence which favors the convective activities forming cumulus cells. The orography of foothills may also enhance the convections. The wind in the upper tropospheric winds attains jet speed over these areas. The distribution of divergence and vorticity in the 925 hPa level shows the evolution of system. The distribution of precipitation shows that the spatial patterns were well captured. Vertical velocity has been plotted along the vertical-horizontal plane oriented in the east-west direction across a high rainfall cell. This shows that the highest development of narrow vertical cell extends up to 100 hPa level. Following the temporal evolution of the system, it is seen that the highest development delayed by around 2 hours. Some mitigation strategies in respect of thunderstorms and associated lighting are also discussed. Dhaka Univ. J. Sci. 68(1): 71-77, 2020 (January)

Coronavirus 2019 (in short, Covid-19), was first found in the Wuhan province of China in December 2019 and has been declared a global pandemic by WHO in March 2020. Since its inception, its rapid spread among nations had initially collapsed the world economy and the increasing death-pool created a strong fear among people as the virus spread through human contact. Initially doctors struggled to diagnose the increasing number of patients as there was less availability of testing kits and failed to treat people efficiently which ultimately led to the collapse of the health sector of several countries. To help doctors primarily diagnose the virus, researchers around the world have come up with some radiology imaging techniques using the Convolutional Neural Network (CNN). While some of them worked on X-ray images and some others on CT scan images, very few of them worked on both the image types where their works are limited to detecting only covid and normal cases and none of them performed any comparative analysis between the performance of these two image types as far as our knowledge goes. This, therefore, has insisted us to perform a comparative analysis between X-ray and CT scan images. Thus we came up with a novel CNN model named CoroPy which works for both the image types and can detect normal, Covid-19 and viral pneumonia with great accuracy and shows that X-ray images have overall better performance.

A reverse phase liquid chromatographic method for estimation of Aceclofenac in bulk drug and tablet dosage form was developed and validated. The chromatographic conditions to achieve the highest performance parameters using octylsilyl column with guard filter were optimized. The separation was carried out using a mobile phase containing 10 mM Phosphate Buffer, pH 2.1 and methanol (30:70% v/v) pumped at a flow rate of 1.0 mL/min with detection at 272 nm. The method was shown to be linear in 19.8–148.5 μg/mL concentration range (regression coefficient of 0.999). The limit of detection (LOD) and limit of quantification (LOQ) was found to be 0.0692 μg/mL and 0.2076 μg/mL, respectively. The accuracy of the method was assessed by adding fixed amount of pre-analyzed sample to different standard solutions (80%, 100%, and 120% of the tested concentration) in triplicate. The percentage mean recoveries were 97.91% to 100.39% with %RSD values of 0.64–0.79. The method was found to be precise with %RSD value of 1.13 and 1.60 for intraday and interday precision study, respectively. The method specificity and robustness were also established. New and sensitive HPLC method for estimation of Aceclofenac has been developed, in respect to the reviewed analytical methods.

A new bioactive naphthoquinone dimer, lawsonol[2-(1,4-dioxo-1,4-dihydronaphthalen-2-yloxy)-3-hydroxynaphthalene-1,4-dione] (1), was isolated from the leaves of Lawsonia alba. Its structure was established on the basis of spectral data, including 2D NMR and HR-MS. Compound 1 exhibited in vitro antibacterial activity against Bacillus megaterium, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.

This article was published in the Annual Research and Review in Biology [© 2017 Hossain et al.] and the definite version is available at : http://doi.org/10.9734/ARRB/2017/35692 The Journal's website is at: http://www.sciencedomain.org/abstract/20787

Alzheimer’s disease (AD) is a progressive neurodegenerative disease that causes problems with memory, thinking, and behavior. Currently, there is no drug that can reduce the pathological events of this degenerative disease but symptomatic relief is possible that can abate the disease condition. N-methyl-D-aspartate (NMDA) receptors exert a critical role for synaptic plasticity as well as transmission. Overstimulation of glutamate receptors, predominantly NMDA type, may cause excitotoxic effects on neurons and is recommended as a mechanism for neurodegeneration. Atypical activation of the NMDA receptor has been suggested for AD by synaptic dysfunction. NMDA receptor antagonists especially memantine block the NMDA receptor and can reduce the influx of calcium (Ca2+) ions into neuron, thus, toxic intracellular events are not activated. This review represents the role of NMDA receptors antagonists as potential therapeutic agents to reduce AD. Moreover, this review highlights the repositioning of memantine as a potential novel therapeutic multitargeting agent for AD.

Bangladesh is stated as one of the most natural disaster-prone countries in the world. The geographical setting of the country makes it vulnerable to natural hazards. Among different disasters in Bangladesh, tornado, flood, earthquake, and cyclone are major hazards according to the historical occurrences and their potential damages. For proper disaster management, recognition of the existence of the hazards and identification of the vulnerable areas are first important tasks. Thus, the prime objective of this study was to prepare a district-wise multi-hazard zoning map of Bangladesh. For the purpose, firstly a complete district-wise database of four disasters in Bangladesh was prepared. Comparing scenarios of these hazards in Bangladesh and their corresponding scales all over the world, suitable intensity scales and their corresponding damage risk levels were proposed. For calculation of district-wise individual hazard scores, hazard factors and weighting factors for particular hazards were defined based on the organized district-wise historical disaster database of Bangladesh through consultation with experts from relative fields. After that, district-wise individual and multi-hazard scores were calculated. Then, the districts of Bangladesh were subdivided into three zones based on calculated multi-hazard scores. Finally, district-wise multi-hazard zoning map of Bangladesh was prepared. The research findings are crucial and important for policy-makers for decision-making regarding disaster management strategies, i.e. planning for disaster prevention, mitigation, and preparedness actions.

Though Marine Parks in Malaysia are important to protect important marine resources, however, it is degraded due to human activities. In order to properly manage marine parks, economic valuation is necessary to understand the importance of marine resources conservation activities. In this study, tourist’s willingness to pay (WTP) to protect marine resources at Pulau Perhentian Marine Park (PPMP) was carried out with contingent valuation method. Both single-bounded and double-bounded dichotomous choice contingent valuation methods were used to estimate tourists WTP. A total of 250 tourists were interviewed. The results showed that median WTP ranged between RM17.98 to RM21.72 and based on the number of tourist’s arrivals in 2011, the aggregate benefit at PPMP would be ranged from 1.62 to 1.96 million, respectively. The results of the study could be beneficial to the Marine Park authority in setting appropriate entrance fee at PPMP and taking the adequate conservation activities to protect marine environment and resources to deteriorate further.

Recurrent outbreaks of marine pufferfish poisoning in Bangladesh highlight the need to understand the context in which the outbreaks occurred. In a recent outbreak investigation, a multidisciplinary team conducted a mixed-method study to identify the demography and clinical manifestation of the victims and to explore different uses of pufferfish, and local buying, selling, and processing practices. The outbreak primarily affected a low income household where an elderly woman collected and cooked pufferfish egg curry. Nine persons consumed the curry, and symptoms developed in 6 (67%) of these persons. Symptoms included vomiting, diarrhea, paresis, and tingling sensation; 2 (22%) persons died. The unstable income of the affected family, food crisis, and the public disposal of unsafe pufferfish byproducts all contributed to the outbreak. A multi-level intervention should be developed and disseminated with the participation of target communities to discourage unsafe discarding of pufferfish scraps and to improve the community knowledge about the risk of consuming pufferfish.

Foreign Direct Investment (FDI) plays a significant role in the economic development of a country especially for the developing countries. Bangladesh also pays much attention on the FDI inflow over the last decades. Economic development of Bangladesh is largely dependent on FDI inflow but over the last few decades the FDI inflow was not consistent. This study was conducted to find out the reason of fluctuation on FDI inflows in Bangladesh as well as its obstacles and potentials. Content analysis method was followed and secondary data were collected to analyze the FDI inflows in Bangladesh. It was evident from the study that the major challenges for Bangladesh to create a lucrative and conducive investment climate to the foreign investors. Though the FDI inflow in Bangladesh is increasing gradually but due to political unrest in the country over the last few decades made the investment climate difficult for the foreign investors to keep faith on sustainable business environment. Therefore, strong political will and FDI favorable business climate may be one of the options to increase FDI inflow in Bangladesh. DOI: 10.5901/mjss.2013.v4n2p695