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The physical and dynamical characteristics of pre-monsoon (March–May) thunderstorms (TS) are investigated over Bangladesh using the Weather Research and Forecasting (WRF) model. The model was run for 24-h using 6-hourly data sets as initial and lateral boundary conditions. The Milbrandt cloud microphysics scheme, Krain–Fritsch cumulus scheme, and Yonsei University planetary boundary layer are found to be the best combination by comparing the root mean square error of rainfall from 18 sensitivity experiments. The synoptic condition and atmospheric instability associated with three TS cases have been analyzed based on mean sea level pressure, convective available potential energy (CAPE), and thermodynamic indices. CAPE is found between 500 and 2700 J kg−1 at 0000 UTC for the TS cases. The presence of low-level southerly wind from the Bay of Bengal and upper-level westerly or north-westerly wind with speeds ranging from 5 to 30 m s−1 is found during the storms. The cloud characteristics and intensity were investigated based on Doppler Weather Radar and INSAT 3DR satellite observations. Cloud micro-physical hydrometeors and other composite features (e.g., cloud top and core precipitation altitude, length of squall line) were also studied by the model and then compared with available observed values. For 24-h rainfall, 2 × 2 contingency tables are computed using Model Evaluation Tools. Categorical skill scores such as proportion correct, frequency bias index, probability of false detection, false alarm ratio, and Gilbert skill score were calculated to evaluate the model's performance. The forecast goodness is found to be reasonably satisfactory after analyzing the significance of the skill scores.

Today, the internet has become so interwoven in our lives that it is difficult to fathom life without it. Technology advancements have led to the emergence of digital media as a significant aspect of our lives, the growing use of mobile information, and social media, which provide platforms for easy global interaction. Technology has many advantages, but it also puts people at risk. As the amount of crimes committed online has multiplied, digital media has become a haven for crooks. The advantages of the internet are no longer a mystery to anyone, and the most recent social media platform is open to anyone. The anonymity it offers and the creation of a genuine atmosphere where users may connect, swap photos, meet others, play games, fall in love, argue, etc. without ever having met in person are the main draws of social media. The exploitation of a victim's name, residence, location, and other personal information by criminals is now, however, all too typical, particularly in situations involving women. Due to the confidentiality and fakeness that are present in social media, as well as jurisdictional concerns, cybercrime has become more prevalent among people of all ages and is now a global problem. The study describes and discusses the effects of digital media on young people as well as the reasons behind the increase in cybercrime on social media. The study addresses the common types of cybercrime that happen there as well as the role of the law in dealing with and preventing it on social media. The research makes numerous recommendations for completely and sufficiently teaching the nation's children about the dangers of cybercriminals.

We have studied reflection spectra of dye-doped and undoped polymers deposited onto Ag and Au substrates and found anomalous dips in the UV spectral range. On top of Ag substrates, the λ ∼ 375 nm dips were observed in undoped PMMA, PVP, and PS polymers as well as PMMA doped with Rh590 and HITC laser dyes. In silver-based samples, the spectral positions of the observed reflection dips were close to singularities in the refractive indexes of surface plasmon polaritons (SPPs) propagating at the interface between Ag and polymer. The latter singularities can tentatively explain the λ ∼ 375 nm reflection dips, if the scattering of Ag and polymeric films is large enough to launch SPP without any prism or grating. The dips observed in reflection of Rh590:PMMA and HITC:PMMA on top of Au, were more pronounced than those on Ag, broader, shifted to shorter wavelengths, and their spectral positions had large standard deviations. Furthermore, no anomalous dips in gold-based samples were observed in the reflection spectra of undoped PMMA, PVP, and PS polymers, and a modest singularity in the SPP refractive index, predicted theoretically at λ ∼ 500 nm, cannot explain the dips in the UV reflection spectra observed experimentally. It appears likely that the origin of the reflection dips on top of Au substrates is different from that on top of Ag substrates.

Fog causes severe hazards in the fields of aviation, transportation, agriculture and public health over Dhaka, Bangladesh during the winter season every year. The characterization of fog occurrences, its onset, duration and dissipation time over Hazrat Shahjalal International Airport, Dhaka are the topics of interest in the present study. Attempts have therefore been made to investigate the climatological perspectives of fog over Dhaka, Bangladesh by conducting two selected dense fog events occurred during 24-25 December 2019 and 14-15 January 2020 using WRF-ARW model. The model performance is evaluated by analyzing different meteorological parameters namely visibility, relative humidity, temperature, and wind. The model outputs have been compared with METAR data from Dhaka Airport, Sounding data and INSAT 3D satellite images for validation purpose. Considering RMSE, the model underestimates of relative humidity. Model simulations are good for other meteorological parameters. Thermodynamic analysis reveals that calm wind persists at surface level during fog formation, southwesterly dry wind was over Dhaka and inversion layer is found to persist in the lower troposphere over Dhaka during the event dates. It is observed in the satellite images that fog/low-level cloud was present over Dhaka during the fog events. The Dhaka University Journal of Earth and Environmental Sciences, Vol. 9(1), 2020, P 39-47

The underutilized

ObjectiveWe aimed to rapidly assess the health system impact of COVID-19 in the urban slums of Bangladesh.DesignSetting and participantsA cross-sectional survey among 476 households was conducted during October–December 2020 in five selected urban slums of Dhaka North, Dhaka South and Gazipur City Corporation. In-depth interviews with purposively selected 22 slum dwellers and key informant interviews with 16 local healthcare providers and four policymakers and technical experts were also conducted.Outcome measuresPercentage of people suffering from general illness, percentage of people suffering from chronic illness, percentage of people seeking healthcare, percentage of people seeking maternal care, health system challenges resulting from COVID-19.ResultsAbout 12% of members suffered from general illness and 25% reported chronic illness. Over 80% sought healthcare and the majority sought care from informal healthcare providers. 39% of the recently delivered women sought healthcare in 3 months preceding the survey. An overall reduction in healthcare use was reported during the lockdown period compared with prepandemic time. Mismanagement and inefficient use of resources were reported as challenges of health financing during the pandemic. Health information sharing was inadequate at the urban slums, resulting from the lack of community and stakeholder engagement (51% received COVID-19-related information, 49% of respondents knew about the national hotline number for COVID-19 treatment). Shortage of human resources for health was reported to be acute during the pandemic, resulting from the shortage of specialist doctors and uneven distribution of health workforce. COVID-19 test was inadequate due to the lack of adequate test facilities and stigma associated with COVID-19. Lack of strong leadership and stakeholder engagement was seen as the barriers to effective pandemic management.ConclusionThe findings of the current study are expected to support the government in tailoring interventions and allocating resources more efficiently and timely during a pandemic.

Introduction:Psychological stress from the ongoing coronavirus disease 2019 (COVID-19) pandemic can potentially aggravate the course of several stress-sensitive skin and hair diseases. This study aimed to determine the potential association of COVID-19 stress with hair diseases, such as telogen effluvium (TE), alopecia areata (AA), and seborrheic dermatitis (SD), among medical students in Bangladesh.MethodsThis online-based cross-sectional study was conducted among 404 medical students of Bangladesh using a self-administered questionnaire, including sociodemographic information, status of hair diseases (i.e., TE, AA, and SD), COVID-19 fear scale, impact of event scale specific for COVID-19 (IES-COVID-19), and COVID-19 student stress questionnaire (CSSQ) scale, to determine pandemic-related stress. The logistic regression model was used to analyze the association.ResultsOverall prevalence of TE, AA, and SD was 61.1, 24.7, and 57.7%, respectively, with female predominance in case of TE and male predominance in case of AA and SD. More than half of the participants had COVID-19-related fear and traumatic stress symptoms. In the multiple logistic regression model, smoking [adjusted odds ratio (aOR) 2.93, 95% CI 1.29–6.65 for AA and aOR 4.19, 95% CI 1.83–9.56 for TE], COVID-19-related fear (aOR 1.70, 95% CI 1.01–2.89 for AA and aOR 2.620, 95% CI 1.25–5.48 for TE), and COVID-19-related traumatic stress symptoms (aOR 1.84, 95% CI 1.08–3.13 for AA, aOR 2.61, 95% CI 1.19–5.68 for TE, and aOR 1.92, 95% CI 1.14–3.25 for SD) were the risk factors of hair fall disorders.ConclusionOur study showed that a large number of medical students experienced TE, AA, and SD during the pandemic era. COVID-19-related stress and fear potentially have an association with these diseases.

not available J Bangladesh Coll Phys Surg 2022; 40: 116-117

The major aims of this study were mainly to determine and describe the extent of farmers’ crop productivity and also explore the relationship between the 12 selected characteristics of the farmers with their crop productivity level. The study was designed with a mixed-method approach where both qualitative and quantitative analyses are blended in a rational way to have a deeper understanding of research problems. The study was conducted in Dumki Upazilla under Patuakhali district, Bangladesh. Simple random sampling technique was used to select 110 farmers except landless engaged in crop production. Data were collected by face to face interview using a pre-tested interview schedule during the period from March 10 to April 15, 2016. Data were analyzed using descriptive statistical measures and computer software like SPSS. Pearson's Product Moment coefficient of correlation results showed that out of 12 independent variables, the correlation coefficients of 7 variables had a positive and significant relationship with their level of crop productivity. The stepwise multiple regression analyses stated that only 4 variables such as communication exposure, innovativeness, risk orientation and training experience had a significant contribution to the farmers' crop productivity level and also accounted for 52.8 per cent of the total variation in productivity index. This study also showed some problems which were faced by the farmers during crop production. If these problems can be solved, the farmers’ crop productivity level will be increased.

Conducting polymers and their metals or metal oxides-based composites are promising for applications in aerospace engineering, construction, computer chips, electronic circuits, energy storage systems, catalysis of reaction and so on. Supercapacitor electrodes and devices comprising polymers/metal oxides composites are envisaged to bridge the gap between existing carbon-based supercapacitors and batteries to form units of intermediate specific energy. In this work, polyaniline (PAni) and its composite with MnO2 were successfully deposited by electrochemical method. Simultaneous polymerization of aniline to PAni, and in situ formation and incorporation of MnO2 into the PAni matrix, and their deposition on Fe substrate took place during the cycling of potential in oxalic acid solution containing aniline and a salt of manganese. Elemental characterization and investigation of morphology and microstructure of the deposits were performed by infra-red, UV–visible reflectance and energy dispersive X-ray spectroscopy and scanning electron microscopy. The band gap energy of PAni was substantially higher compared to PAni/MnO2 composite. The specific capacitance of the electrodes prepared was investigated using cyclic voltammetry and charge–discharge test by chronopotentiometry. Fe-PAni and Fe-PAni/MnO2 composite modified electrodes exhibited excellent supercapacitive property, energy density and power density compared to their bulk Fe electrodes in aqueous sodium sulfate solution.

Objectives: To test the hypothesis that there is no difference between adults with Class I crowded (CICR) and Class I normal (CIN) occlusions with respect to width of the maxillary and mandibular arches and gender comparisons. Materials and Method: In this cross sectional study, 52 pairs of study models were selected from the patients and students of the Orthodontics and Dentofacial Orthopedics Department of Dhaka Dental Collage and Hospital and were divided into two groups, 27 pair of dental casts with normal occlusion, 25 pair of dental casts with Class I crowded malocclusion including equal males and female samples. Results: The result of this study evaluated two study groups (Normal occlusion and Class I crowded ). Between different arch dimension maxillary arch widths were found to have significantly smaller in Class I crowded malocclusion compared with Normal Class I occlusion. Conclusion: In conclusion, the hypothesis was partially rejected by the finding of the study. Ban J Orthod & Dentofac Orthop, April 2017; Vol-7 (1-2), P.1-5

Congenital myasthenic syndromes (CMS) comprise a heterogeneous group of rare inherited diseases in which the neuromuscular transmission in the motor plate is compromised by one or more genetic pathophysiological specific mechanisms are characterized by fatigable weakness of skeletal muscle (e.g., ocular, bulbar, limb muscles) with onset at or shortly after birth or in early childhood; rarely, symptoms may not manifest until later in childhood. The diagnosis of CMS is based on clinical findings, a decremental EMG response of the compound muscle action potential (CMAP) on low-frequency (2- 3 Hz) stimulation, absence of anti-acetylcholine receptor (AChR) and anti-MuSK antibodies in the serum, a positive response to acetylcholinesterase (AchE) inhibitors and lack of improvement of clinical symptoms with immunosuppressive therapy. Pathogenic variants in one of multiple genes encoding proteins expressed at the neuromuscular junction are currently known to be associated with subtypes of CMS. The most commonly associated genes include: CHAT, CHRNE, COLQ, DOK7, GFPT1 and RAPSN. We studied on a sibling presented with progressive fatigability and fluctuating ptosis with frequent exacerbations of muscle weakness during infections since infancy. On both cases CT scan of chest were negative for thymoma, antibodies against the acetylcholine receptor (AChR) and the muscle specific kinase (MuSK) were negative and decremental response on electrophysiological study of Repetitive nerve stimulation (RNS) and EMG were consistent with disease of neuromuscular junction (post synaptic) and they were only on pyridostigmine for long time with marked improvement of symptoms and signs. Considering all scenario both of our cases mostly fits with the autosomal recessive, post synaptic CMS associated with Rapsyn deficiency. Objective : As in Bangladesh, there is inadequate data on the epidemiological profile of CMS, our aim is to describe these cases for their rarity and the difficulty encountered in diagnosis as they are easily confused with Juvenile Myasthenia Gravis (JMG) and familial myopathies. As both the cases are very rare, it should be an original article. Bangladesh Journal of Neuroscience 2019; Vol. 35 (2): 95-103

Changes in the climate due to anthropogenic and natural variation are indicated by parameters including temperature and rainfall. Climate change variability with changing trends of the two have been unpredictable and unprecedented globally leading to changing weather patterns, natural disasters, leading to sectoral impacts on food and water security, livelihood, human health among others. This research analyses the changing patterns of these parameters over the last 35/37 years of Satkhira district of Bangladesh to assess the state and trend across spatial and temporal dimensions. Such, the study validates to rationalize the observed seasonal changes that persist in Satkhira of Bangladesh. Both in terms of intensity and frequency of the occurrences of natural disasters, the series of natural events have been triangulated, with impacts and vulnerability being assessed from temperature variations, erratic rainfall, cyclone, flood and water logging etc. The study’s prime contribution remains in attribution of climate change in relation contextual circumstances in the region including sea level rise, salinity intrusion. Therefore, the risk and climatic hazards and its resulting impacts over time has been assessed to draw deeper connection between theoretical and practical values. The series of analyses also draw conclusion that assets are at risk from changing climatic condition.

BACKGROUND The world has been grappling with the COVID-19 pandemic, a dire public health crisis, since December 2019. Preventive and control measures have been adopted to reduce the spread of COVID-19. To date, the public’s knowledge, attitudes, and practices regarding COVID-19 across Bangladesh have been poorly understood. Therefore, it is important to assess people’s knowledge, attitudes, and practices (KAP) toward the disease and suggest appropriate strategies to combat COVID-19 effectively. OBJECTIVE This study aimed to assess the KAP of Bangladeshi people toward COVID-19 and to identify their determinants. METHODS We conducted a country-wide cross-sectional telephonic survey from May 7 to 29, 2020. A purposive sampling method was applied, and adult Bangladeshi citizens who have mobile phones were approached to participate in the survey. Interviews were conducted based on verbal consent. Multiple logistic regression analyses and several tests were performed to identify the factors associated with KAP related to COVID-19. RESULTS A total of 492 of 576 Bangladeshi adults aged 18 years and above completed the interview, with a response rate of 85.4% (492/576). Of the 492 participants, 321 (65.2%) were male, and 304 (61.8%) lived in a rural area. Mean scores for knowledge, attitudes, and practices were 10.56 (SD 2.86), 1.24 (SD 0.83), and 3.17 (SD 1.5), respectively. Among the 492 respondents, 273 (55.5%) had poor knowledge, and 251 (49%) expressed a negative attitude; 192 out of 359 respondents (53.5%) had poor practices toward COVID-19. Mean scores of knowledge, attitudes, and practices differed significantly across various demographic and socioeconomic groups. Rural residents had lower mean scores of knowledge (mean 9.8, SD 3.1, PPr=0.21, Pr=0.45, Pr=0.27, P CONCLUSIONS Evidence-informed and context-specific risk communication and community engagement, and a social and behavior change communication strategy against COVID-19 should be developed in Bangladesh based on the findings of this study, targeting different socioeconomic groups.

This chapter presents a very brief overview of the impacts of climate change on water and relevant sectors in South Asia. It provides an overview of the basic concepts and science of climate change. The chapter includes the observed changes in the climate system and the parameters in South Asia including Bangladesh. It describes the impacts of climate change on water resources and the connected ecosystems in South Asia with special reference to Bangladesh. The chapter also provides an overview on the global and regional responses to address climate change. Climate Change is basically the changes of climate over a time period that usually ranges from decades to centuries. Most of the climate models estimate that precipitation will increase during the summer monsoon because they estimate that air over land will get warmer than air over oceans in the summer. The rapid growth of population in South-Asia is putting additional pressure on the natural resources including water.

The world is grappling with Covid-19, a dire public health crisis. Preventive and control measures are adopted to reduce the spread of COVID-19. It is important to know the knowledge, attitude, and practice (KAP) of people towards this pandemic to suggest appropriate coping strategies. The aim of this study was to assess the KAP of Bangladeshi people towards Covid-19 and determinants of those KAPs. We conducted a cross-sectional survey of 492 Bangladeshi people aged above 18 years from May 7 to 29, 2020 throughout the country. Simple and multiple logistic regression analyses were conducted to identify the factors associated with KAP on COVID-19. About 45% of respondents had good knowledge, 49% of respondents expressed positive attitude towards controlling of COVID-19 and 24% of respondents had favorable practice towards COVID-19. Almost three fourths of the respondents went outside home during the lockdown period. Furthermore, the study found that good knowledge and attitude were associated with better practice of COVID-19 health measures. An evidence informed and context specific risk communication and community engagement, and a social and behavior change communication strategy against COVID-19 should be developed in Bangladesh, based on the findings of this study, targeting different socio-economic groups.

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The Ganges–Brahmaputra–Meghna river system carries the world's third-largest fresh water discharge and Brahmaputra alone carries about 67% of the total annual flow of Bangladesh. Climate change will be expected to alter the hydrological cycles and the flow regime of these basins. Assessment of the fresh water availability of the Brahmaputra Basin in the future under climate change condition is crucial for both society and the ecosystem. SWAT, a semi-distributed physically based hydrological model, has been applied to investigate hydrological response of the basin. However, it is a challenging task to calibrate and validate models over this ungauged and poor data basin. A model derived by using gridded rainfall data from the Tropical Rainfall Measuring Mission (TRMM) satellite and temperature data from reanalysis product ERA-Interim provides acceptable calibration and validation. Using the SWAT-CUP with SUFI-2 algorithm, sensitivity analysis of model parameters was examined. A calibrated model was derived using new climate change projection data from the multi-model ensemble CMIP5 Project over the South Asia CORDEX domain. The uncertainty of predicting monsoon flow is less than that of pre-monsoon flow. Most of the regional climate models (RCMs) show an increasing tendency of the discharge of Brahmaputra River at Bahadurabad station during monsoon, when flood usually occurs in Bangladesh.

Climate-induced hazards are adversely affecting the pond ecosystems in Bangladesh. Most of the poor communities collect water from isolated ponds for drinking and other domestic needs. This paper explores how the small pond ecosystems and associated livelihoods of the coastal communities are vulnerable and argues that the pond ecosystem can be a potential resource base for community based adaptation in the coastal regions of Bangladesh. A set of quantitative and qualitative tools were applied to 309 households across five villages. The study showed that 96% of the respondents are dependent on pond water for drinking. More than 50% households expressed that temperature, rainfall variations and salinity intrusion, directly and indirectly, affect the pond water. Physical parameter values of temperature, pH and salinity from the ponds showed changes across different seasons. Drinking water scarcity during pre-monsoon (March–May), winter (Dec–Feb), disaster and immediate post-disaster period among the communities is high. Salinity intrusion and surface runoff caused by excessive rainfall in short periods also cause deterioration in the quality of pond water. However, successful examples of pond water usage emerged through the discussions, especially during a post-disaster crisis, which strengthens the idea that ponds could be a resource base for community-based adaptation in the coast of Bangladesh.

A multi-model ensemble provides useful information about the uncertainty of the future changes of climate. High-emission scenarios using representative concentration pathways (RCP8.5) of the Fifth Phase Coupled Model Inter-comparison Project (CMIP5) in the Intergovernmental Panel on Climate Change (IPCC) also aids to capture the possible extremity of the climate change. Using the CMIP5 regional climate modelling predictions, this study analyses the distribution of the temperature and precipitation in Bangladesh in the recent years (1971–2000) and in three future periods (2010–2040, 2041–2070 and 2070–2100) considering RCP8.5 scenarios. Climate changes are expressed in terms of 30-year return values of annual near-surface temperature and 24-h precipitation amounts. At the end of the century, the mean temperature increase over Bangladesh among the 11 RCMs will vary from 5.77 to 3.24 °C. Spatial analysis of the 11 RCMs exhibited that the southwest and the south central parts of Bangladesh will experience a greater temperature rise in the future. Possible changes in rainfall are also exhibited both temporally and spatially. Based on the analysis of all the RCMs, a significant increase of rainfall in the pre- and post-monsoon period is observed. It is also evident that monsoon rainfall will not increase in comparison with pre-monsoon season. Zonal statistics of 64 districts of Bangladesh are also conducted for the 2020s, 2050s and 2080s to find out the most exposed regions in terms of the highest rise in temperature and changes in precipitation.

The study aimed at analyzing the fluctuation, and production-price relationship of ginger in Bangladesh. Nineteen years (1975 to 2013) time series data of area, production and prices of ginger, collected from Bangladesh Bureau of Statistics were used to analyze the simplest method for fluctuation, and the Koyck model of distributed lag. The extent of annual price fluctuation of ginger ranged between -50 to 63 percent, while the fluctuation of area, production and yield ranged between-5 to 13, -17 to 22 and -20 to 11 percent, respectively. The study revealed that ginger production in Bangladesh had been influenced by the average price lag value formed in the market. The most striking result of the study was that the time required to get an effect on ginger production for the changes of ginger prices in Bangladesh was 19.83 years. This result shows that the farmers are very enthusiastic for growing ginger, the widely grown major spice crop. The correlation/regression coefficients indicated that the changes in lag values of the prices had a positive influence on production. It may be recommended that to keep the ginger price fluctuation under control, sustainable ginger farming and establishment of an efficient marketing organization is necessary.The Agriculturists 2017; 15(1) 01-09

The student’s performance plays an important role in producing the best quality graduate who will responsible for the country’s economic growth and social development. The labor market also concerns with student’s performance because the fresh graduate students are considered as an employee depends on their academic performance. So, identification of the reason behind student’s performance variation provides valuable information for planning education and policies. Many researchers try to find out the reason with different types of data mining approaches in different countries. However, none of them worked with Bangladeshi students. This paper proposed a model for identifying the key factors of variation Bangladeshi students’ academic performance and predicts their results. This paper proposes a model which able to identify the students who need special attention. Different types of feature selection methods were used such as Co-relation, Chi-Square and Euclidean distance to select valuable features and feature selections result through decision tree, Naive Bayes, K-nearest neighbor and Artificial Neural Network classifiers algorithm were compared. The performance analysis is done by using student SGPA and review on given facilities from a university. From the performance analysis result it is found that, decreasing number of classes in dataset, the Artificial Neural Network (ANN) (93.70%) performs better than Decision Tree (DT) (92.18%), K-Nearest Neighbors (KNN) (77.74%) and Naive Bayes (NB) (68.33%). However, an increasing number of classes in dataset the DT perform better than ANN, KNN, NB.