Search

Instability is an inherent aspect of agriculture due to its reliance on weather conditions, resulting in substantial fluctuations in crop area, production and yield. Mung bean (Vigna radiata) is one of Bangladesh's most important pulses. It is highly valued for its nutritional composition and also helps improve soil health. This study focused on analyzing the changes in the cultivation area, production and yield of mung bean in Bangladesh through growth rate and instability analysis based on secondary data over a 40-year period (1981-2020). The entire timeframe was divided into four sub-periods:1981-1990,1991-2000,2001-2010 and 2011-2020 allowing for analysis using various statistical tools. Growth rates were calculated by fitting an exponential growth function, while instability was assessed using the Cuddy-Della Valle index. The analysis revealed that the area and production of mung beans had increased. The change in area and yield contributed respectively 51.3% and 46.8% to changes in the mean production of mung bean at the national level. Though the mung bean yields increased significantly, the rate of growth is slow, and it is insufficient to meet our country's demand. The analysis also revealed that the area, production, and yield of mung bean were not stable during the study period. [ABSTRACT FROM AUTHOR]

This research evaluates the effectiveness of chitosan and guava leaf extract (GLE) as preservativesto increase the storage life of fruits. Chitosan was prepared from chitin extracted from shrimp shells. GLE was extracted from mature green leaves by the hot water (80°C) extraction method. Chitosan with the solid concentrations of 1.0, 1.5 and 2.0%, and GLE with 0.5% were sprayed on banana, carambola and tomatoto create a surface coating and were stored at 25±2°C temperature and 85±5% relative humidity for 12 days. To evaluate the effectiveness of chitosan and GLE, moisture content, weight loss percentage (WLP), pH value of juice from fruits, carbohydrate content, protein contents and percentage disease index (PDI) were measured after 12 days storage. People's perceptions were also assessed for identifying the effectiveness of the preservatives. From the results, it was found that the application of 2% chitosan showed the lowest weight loss 6.58% for banana compared to the control samples. Protein and carbohydrate content were the highest 1.96 and 14.97% respectively when there was 2% chitosan application whereas GLE also showed similar results. The PDI was also lower 87.23 and 86.52% for banana coated with 2% chitosan and 0.5% GLE, respectively. Therefore, it is concluded that the chitosan and GLE can be applied as bio-preservative to extend the shelf life of the fruits without compromising their quality. [ABSTRACT FROM AUTHOR]

In this study, tungsten di-sulphide (WS2), one of these key transition-metal dichalcogenide (TMDC) materials, is used as solar cell absorber material with a suitable solar cell configuration and analyzed by SCAPS-1D. Other main focuses include optimum absorber layer thickness, suitable material for buffer layer instead of CdS and effect of operating temperature on solar cell performance. An efficiency of 19.48% (with Voc of 0.90 V, Jsc of 24.94 mA/cm² and fill factor of 0.86) has been found for the cell with CdS based buffer layer. High efficiency WS2 solar cells have the optimized absorber thickness in the range of 2 µm to 3 µm. Moreover, the desired thickness of the buffer layer is observed in between 40-60 nm. Among different types (ZnO, ZnSe, ZnS, CdS and In2S3) of buffer layers, ZnO based WS2 solar cell shows the potential to reach out the highest efficiency of 25.71%. However, cell with ZnO buffer layer shows a temperature gradient of -0.24%/K. All these simulation results provide significant hints that may lead to higher efficiency of WS2 solar cells with beneficial experimental studies in practical implementation. [ABSTRACT FROM AUTHOR]

Cadmium Telluride (CdTe) thin films were deposited on cleaned soda lime glass substrates at 300°C by RF magnetron sputtering technique. Thin films of Cu were subsequently deposited on top of CdCl2 treated CdTe thin films for 2 min, 5 min, 10 min and 15 min corresponding to a thickness of 20 nm, 50 nm, 90 nm and 120 nm, respectively by sputtering at a substrate temperature of 200°C. CdTe and Cu stacks were annealed at 200°C for 15 minutes in a vacuum furnace. The influence of different Cu concentration on the structural, topographical, optical, electrical and morphological properties of sputtered CdTe thin films were then investigated by XRD, AFM, UV-Vis, Hall Effect measurement and FESEM, respectively. From the XRD analysis, a sharp CdTe peak corresponding to the (111)cub plane at 2=23.8° and a low intensity Cu2Te peak representing (200)cub reflection plane at around 2=24.8° were found for different Cu growth time on CdTe. There was no existence of Cu2Te peak when Cu was deposited on top of CdTe for 2 min. The relative peak intensity was higher for 10 min Cu growth on CdTe. Significant changes were observed in the films surface roughness due to the different Cu concentration. The average and RMS roughness values showed rising trend for higher Cu concentration. The band gap values remained around 1.50 eV for all the films. Electrical measurements showed p-type conductivity and highly degenerate semiconducting behavior with highest carrier concentration of (7.5x1018 cm-3) as achieved for 10 min of Cu growth. Some preliminary CdTe based photovoltaic devices were also fabricated without any process or structural optimization, where the highest photovoltaic conversion efficiency of 3.77% (Voc = 0.42 V, Jsc = 26.4 mA/cm2 and Fill Factor = 0.34) was obtained for the CdTe films having 50 nm thick Cu layer deposited on top. [ABSTRACT FROM AUTHOR]

CdTe is considered as one of the most auspicious materials as absorber layer for fabricating thin film solar cells with highest efficiency of 22.1% at present reported by First Solar Inc. Growth conditions and parameters are crucial aspects to acquire high quality and pin hole free thin absorber layer. In this study, a comparative analysis has been executed for close-spaced sublimation (CSS) grown CdTe thin films in both dynamic and static conditions. These growth conditions may have dependence on the way of inert gas flow during deposition. Deposited films have been characterized by using XRD, FESEM, AFM and Hall Effect Measurement. The XRD pattern reveals the presence of zinc-blende cubic structure with ideal orientation (111) confirming polycrystalline nature. The FESEM characterization illustrates the films that are homogenous, uniform and have less crystal defects. AFM analysis has been carried out to know the surface topography and roughness which has the increasing trend for thicker films. Moreover, the electrical parameters such as carrier concentration, mobility, resistivity, and conductivity have been measured from Hall Effect measurement. [ABSTRACT FROM AUTHOR]

In this study, the influence of laser annealing on the structural, optical and electrical properties of thermally evaporated CdTe thin films has been investigated. CdTe thin films were deposited by thermal evaporation at different power. Thermally evaporated CdTe thin films were then subjected to post deposition laser annealing. The laser annealing was done by illuminating the films by pulsed laser beam with combined wavelengths of 1064nm and 532nm. Both the as-deposited and laser-annealed CdTe thin films were characterized using XRD, AFM, FESEM integrated with EDS, UV-Vis spectroscopy and Hall Effect measurement system. The as-grown and laser-annealed CdTe thin films deposited on soda lime glass showed polycrystalline nature with a mixture of zinc-blende (cubic, C) and wurtzite (hexagonal, H) phases. AFM images on the other hand showed increase in R.M.S roughness value after laser annealing. FESEM micrographs revealed the increase in grain size and the EDS results showed that the CdTe films became tellurium rich upon laser annealing. The band gap of the films increased after laser annealing due to the quantum confinement effect as revealed from optical analysis. Hall Effect measurement found different electrical nature of the CdTe thin films after laser annealing. [ABSTRACT FROM AUTHOR]

The aim of the present study was to find methods for enhancing ratesof hydrocarbon biodegradation in gasoline contaminated soil by ex situ bioremediation. Red soil (RS) was treated with gasoline-spilled soil (GS) from a gasoline station and different combinations of amendments were prepared using (i) mixed bacterial consortium (MC), (ii) poultry litter (PL), (iii) coir pith (CP) and (iv) rhamnolipid biosurfactant (BS) produced by Pseudomonas sp. DS10-129. The study was conducted for a period of 90 days during which bacterial growth, hydrocarbondegradation and growth parameters of Phaseolus aureus RoxB includingseed germination, chlorophyll content, shoot and root length were measured. Approximately 67% and 78% of the hydrocarbons were effectively degraded within 60 days in soil samples amended with RS + GS + MC +PL + CP + BS at 0.1% and 1%. Maximum percentage of seed germination,shoot length, root length and chlorophyll content in P. aureus were recorded after 60 days in the above amendments. Further incubation to90 days did not exhibit significant improvements. Statistical analysis using analysis of variance (ANOVA) and Duncan's multiple range test (DMRT) revealed that the level of amendments, incubation time and combination of amendments significantly influenced bacterial growth, hydrocarbon degradation, seed germination and chlorophyll content at a1% probability level. All tested additives MC, PL, CP and rhamnolipid BS had significant positive effects on the bioremediation of GS. [ABSTRACT FROM AUTHOR]

Renal dysfunction following cardiopulmonary bypass is well recognized. The pathophysiology of renal injury is multifactorial and culmination of the interplay of several pathophysiological mechanism. Cardiac surgery requiring cardiopulmonary bypass (CPB) is being carried out on an extended patient population of different age groups and undergoing complex surgical procedure, and thus it places them at an increased risk of renal impairment. Valve replacement surgery is a major and complex surgical procedure requiring CPB. This study was therefore designed to observe the impact of CPB and short term outcome on patients with reduced estimated Glomerular Filtration Rate (eGFR) (60-89ml/min/1.73m²) after valve replacement surgery. This cross-sectional study was conducted in the Department of Cardiac Surgery, National Institute of Cardio Vascular Diseases (NICVD) during the period of January 2015 to August 2016. After fulfillment of enrollment criteria 100 patients were studied for the purpose of the study and they were grouped in two, patients with normal eGFR (≥90ml/min/1.73m²) in Group A and patients with reduced eGFR (60-89ml/min/1.73m²) in Group B. A total of 100 patients, 50 in each group were studied for renal function alteration after valve replacement surgery under cardiopulmonary bypass. The incidence of Acute Kidney Injury (AKI) was higher in Group B. Chi-square test was done and p value was 0.011 which is statistically significant. Postoperative blood loss (ml/hr) (p=0.038), duration of Intensive Care Unit (ICU) stay (in hours) (p=0.009), postoperative hospital stay (days) (p=0.014) was significantly higher and postoperative Urine Output (ml/hr) (p=0.001) was significantly lower in patients with reduced eGFR (60-89ml/min/1.73m²) in Group B. Deterioration of renal function is more in patient with eGFR (60-89ml/min/1.73m²) after valve replacement surgery under cardiopulmonary bypass in comparison with patients with eGFR (≥90ml/min/1.73m²).

The coronavirus disease 2019 (COVID-19), first reported in Wuhan, China is now a major global health threat - a pandemic. Public health control measures are the cornerstones in the fight against COVID-19 in the absence of an effective vaccine or proven treatment. The aim of this review was to explore the historical use case of various public health measures adopted today to tackle COVID-19 spread. Although our knowledge about this novel coronavirus transmission is evolving over time, the fundamental non-pharmaceutical interventions e.g., handwashing, wearing a mask, physical distancing, isolation, quarantine and border control which are adopted globally at present are not new. This review highlighted that historically and religiously similar approaches were practised in the medieval past for controlling disease outbreaks. The successful implementation of the public health control measures largely depends on health systems resilience, community engagement and changes in population behaviour. Combined global efforts are essential to strengthen health systems, improve the capability of research and transparent information sharing with both public and international bodies to combat the pandemic.

Cleft lip and cleft palate, also known as orofacial cleft, is a group of conditions that includes Cleft lip (CL), Cleft palate (CP) and both together (CLP). Cleft lip with/or palate are the major human orofacial congenital malformations seen in live birth as well as in still birth. This descriptive cross sectional study was done to determine how the different types of Cleft lip (CL), Cleft lip with palate (CLP) and Cleft palate (CP) are distributed among Bangladeshi Children. This study was performed at a health screening camp for patients with cleft lip with/or palate at Dhaka Shishu Hospital, Dhaka. A total 30 patients irrespective of their age and gender, presenting with cleft lip with/or palate deformities were included in the study. A questionnaire was constructed to be filled out by the present researcher through a face-to-face interview with the respondent preferably the mother. The data were organized and analyzed through Statistical Package for Social Sciences (SPSS, Version 20). Looking frequencies of different types of cleft lip with/or palate some trends can be noted regarding the laterality, completeness, extent, side involved and involvement of the alveolus. Out of the 14 CL cases, only 1 (7.14%) showed bilateral cleft. This cleft was complete but simple. All the others were unilateral cleft. A vast majority 9(about 65%) of the cleft lips belonged to the unilateral incomplete left sided simple type. One (7.14%) showed unilateral incomplete right sided simple type of CL. Only 2(14.28%) cases involved the alveolus. Out of the 11 CLP cases, unilateral cleft lip was present in 8 (more than 70% cases). Among them 6 cases showed complete cleft lip and 2 cases showed incomplete cleft lip. Out of all CLP cases 1 but all showed complete cleft palate. The most common type of CLP was "unilateral complete left sided compound cleft lip with unilateral complete left sided cleft palate" present in 5 of the children (i.e. more than 45% of the CLP cases and more than 16% of all cleft cases). Out of the 5 CP cases, only 1(20%) had involvement of the uvula plus posterior part of the soft palate. The rest 4(80%) had involvement of soft palate. Cleft lip with/or palate commonly occurred in Bangladeshi children. Genetic and environmental factors cause this birth defect. Therefore, integrated research among those factors is essential to prevent this birth defect.