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The novelty of this work is to fabricate the double-walled (DW) TiO2 nanotube arrays (TNAs) by an anode oxidation method with NH4F-based electrolyte and Zinc counter electrode (CE, c-Zn) and to investigate the photodegradation performance of these TNAs. The structural, optical, and photodegradation performance of TNAs with c-Zn material have been compared to the properties of TNAs with the other two CEs like c-Pt (Platinum) and c-Ti (Titanium). The counter electrode has a tremendous influence on the structural properties and geometrical features of TNAs. The TNAs fabricated with c-Zn have the red-shifted absorption edge with two bandgaps such as 3.15 and 1.78 eV. Interestingly, the TNAs with c-Zn are found as the DW TNAs with outer diameter of 130 ± 3 nm, thinner outer wall thickness of 12 ± 2 nm, and thicker inner wall thickness of 30 ± 2 nm. The photodegradation performance varies with different counter electrodes during the deposition of TNAs by the anode oxidation method. The TNAs sample prepared with c-Zn has shown the highest roughness value of 305.0 nm, photodegradation efficiency of 97.0%, and the rate constant value of 0.00985 min−1 than the other TNAs with c-Pt, c-Ti, and other researcher's data. Moreover, the optical, structural, and surface morphological properties of TNAs have correlated with the photodegradation performance of TNAs prepared with various counter electrodes during deposition.

Purpose: This study attempts to analyze the influence of board structure (board size, board independence, CEO duality, insider ownership) on performance of Bangladeshi listed nonfinancial firms during the post-shock period of stock prices. Methodology: Putting stress on the issue of controlling for any possible endogeneity problems prevails in the effects of structure of board on corporate performance this study employed the Durbin-Wu-Hausman test as the presence of endogeneity severely makes the OLS estimates biased. Therefore, satisfying endogeneity and overidentification tests the observed data have been analyzed by 2SLS as well as OLS regression models. In an attempt to choose the consistent coefficients between OLS and 2SLS a Hausman test was applied. Findings: Results of the study suggest that a board featuring more directors improve accounting measures of performance and a board having more independent directors also significantly assist firms to enhance their market measure of performance. CEO duality is found detrimental to the accounting measures of performance. Apart from, findings support that holding more ownership by insiders leads to enhance firm performance. Thus, it provides empirical evidence to support a view of agency theory that large board, board independence, and insider ownership are good incentives to the firm to monitor and supervise managerial activities and minimize agency problems. Practical Implication: Overall, findings of the study are posing some implications for academics, practitioners, and policy makers in advancing the existing knowledge domain and formulating governance policies in the context of emerging countries like Bangladesh. Originality: The driving force of this work was to investigate how effective the corporate governance directives/notifications in regard to board independence and insider ownership was in protecting the shareholders’ interest during the post-shock period of stock prices in Bangladesh. Therefore, this study provides a robust result with regard to the impacts of reformed corporate governance notification (CGN 2012) on firm performance in Bangladesh.

Diabetes mellitus has become a serious and chronic metabolic disorder that results from a complex interaction of genetic and environmental factors, principally characterized by hyperglycemia, polyuria, and polyphagia. Uncontrolled high blood sugar can result in a host of diabetic complications. Prolonged diabetes leads to serious complications some of which are life-threatening. The prevalence of diabetes patients is rising at epidemic proportions throughout the world. Every year, a major portion of the annual health budget is spent on diabetes and related illnesses. Multiple risk factors are involved in the etiopathogenesis of the disease and turning the disease into an epidemic. Diabetes, for which there is no cure, apparently can be kept under control by maintaining self-care in daily living, effective diabetes education, with comprehensive improvements in knowledge, attitudes, skills, and management. In this review, we focused on the biochemical aspects of diabetes, risk factors including both environmental and genetic, disease complications, diagnosis, management, and currently available medications for the treatment of diabetes.

The Co/TiO2 multilayer thin films were prepared by e-beam evaporation on glass substrate. Each film was consisting of three alternative bilayer of Co and TiO2 and the top layer of the films were Ti...

Pure and antimony doped tin oxide (Sb:SnO2) thin solid films were synthesised through a simple and low-cost nebulised spray pyrolysis (NSP) route. The influence of Sb doping on the different physic...

In this paper, Ba-doped SnO2 (SnO2:Ba), Mg-doped SnO2 (SnO2:Mg) and Ce-doped SnO2 (SnO2:Ce) nanostructured thin films were prepared on the glass substrate via a simple and low-cost nebulizer spray pyrolysis method. The crystal structure and morphology of all the samples were investigated by X-ray diffraction (XRD) and field-emission-scanning electron microscopy (FE-SEM), respectively. XRD results suggest that all the samples are polycrystalline with the tetragonal rutile structure. FE-SEM analysis exhibits a uniform surface morphology with homogenous distribution of grains. The transmittance measurement suggests that SnO2:Ba sample exhibits high transparency above 90% in the visible region. We find that doping causes an increase in the band gap, this behavior is explained by the Burstein–Moss effect. Two emission bands in the ultraviolet and visible regions are observed in the photoluminescence spectra. Hall effect measurement reveals that all the samples are degenerate and exhibit n-type semiconducting nature with carrier concentration in the order of 1018 cm−3. Ba doping induces the lowest resistivity of 0.047 Ω·cm associated with an increase in carrier concentration of 8.38 × 1018 cm−3 and mobility of 15.87 cm2 V−1 s−1. In contrast, the incorporation of Mg and Ce in SnO2 reduces the mobility and conductivity, which may be associated with the grain boundary scattering.

The novelty of this work is to fabricate the Nanosticks (NSs) like CdS sensitizer on the surface of TiO2 electrode by chemical bath deposition (CBD) method with a very high vacuum annealed at 350 °C for 30 min. Whereas, nanocrystalline TiO2 electrodes have been prepared on FTO (SnO2: F) glass by a spin-coating method with high purity (99.99%, Degussa P25) TiO2 powder. The surface of the CdS layer has been covered by NSs like structures which are confirmed by the scanning electron microscope image. The 100 nm of platinum-coated FTO substrate and polysulfide-based electrolyte are used to assemble the Grätzel Solar cell (GSC). The performance of solar cell (SC) based on NSs like CdS has been compared with the nanoparticles (NPs) based CdS sensitized SC, where CdS NPs has synthesized by CBD without any post-annealing. The efficiency of NSs like CdS sensitized SC exhibits 2.44%, which is 2 folds of the efficiency of the CdS NPs sensitized SC. The NSs like CdS sensitized SC shows the highest photocurrent 20.24 mA/cm2 compared to CdS NPs based SC.

Characterization as well as prediction of the secondary and tertiary structure of hypothetical proteins from their amino acid sequences uploaded in databases by in silico approach are the critical issues in computational biology. Severe acute respiratory syndrome–associated coronavirus (SARS-CoV), which is responsible for pneumonia alike diseases, possesses a wide range of proteins of which many are still uncharacterized. The current study was conducted to reveal the physicochemical characteristics and structures of an uncharacterized protein Q6S8D9_SARS of SARS-CoV. Following the common flowchart of characterizing a hypothetical protein, several sophisticated computerized tools e.g., ExPASy Protparam, CD Search, SOPMA, PSIPRED, HHpred, etc. were employed to discover the functions and structures of Q6S8D9_SARS. After delineating the secondary and tertiary structures of the protein, some quality evaluating tools e.g., PROCHECK, ProSA-web etc. were performed to assess the structures and later the active site was identified also by CASTp v.3.0. The protein contains more negatively charged residues than positively charged residues and a high aliphatic index value which make the protein more stable. The 2D and 3D structures modeled by several bioinformatics tools ensured that the proteins had domain in it which indicated it was functional protein having the ability to trouble host antiviral inflammatory cytokine and interferon production pathways. Moreover, active site was found in the protein where ligand could bind. The study was aimed to unveil the features and structures of an uncharacterized protein of SARS-CoV which can be a therapeutic target for development of vaccines against the virus. Further research are needed to accomplish the task.

Background Increased suicide literacy and reduced stigma toward suicide facilitate the care‐seeking for suicidal behavior. However, no attempt has been identified to determine these two vital aspects in Bangladesh. Objectives We aimed to validate the literacy of suicide scale and stigma of suicide scale into Bangla along with the determination of the level of suicide literacy and stigma toward suicide. Methods We conducted this study between April and June 2021. Data were collected from medical school and university students by Google form. We used a questionnaire consisting of four segments (i.e., sociodemographic questionnaire, a questionnaire for suicidal behavior, Bangla literacy of suicide scale [LOSS‐B], and Bangla stigma of suicide scale [SOSS‐B]) for data collection. We tested the psychometric properties of the scales in a sample of 529 students and examined factors associated with suicide stigma and literacy. Results The mean age of the students was 22.61 ± 1.68 (range 18–27) years, 274 (51.8%) were males, 476 (89.9%) were graduate students, and 490 (92.6%) were unmarried. The mean score of LOSS was 4.27 ± 1.99 ranging from 0 to 10. Factor analysis revealed acceptable psychometric properties of SOSS‐B. The literacy was significantly higher in females, students of medicine, having a family history of suicidal attempts, and a history of student nonfatal attempts, while stigma was significantly lower among the females and a history of past attempts. Conclusions This study revealed the level of literacy and stigma and culturally tested the psychometric properties of the LOSS‐B and SOSS‐B among university students in Bangladesh., This is the first attempt to determine the level of suicide literacy and stigma in Bangladesh. We tested the psychometric properties of the literacy and stigma of suicide scales in Bangla. The literacy was significantly higher in females, students of medicine, having a family history of suicidal attempts, and a history of student non‐fatal attempts.

The Co/TiO2 multilayer thin films have been deposited by e-beam evaporation method on glass substrates in vacuum and annealed in air at 773 K for 1 h. The crystal structure, surface morphology, optical properties, electrical properties and magnetic properties of Co/TiO2 multilayer thin films have been systematically investigated. The results showed that the particle sizes were significantly reduced when the samples are annealed and the enlargement of particle size occurred when the samples thickness is increased. The spectroscopic analysis exhibited enhanced transmittance and higher optical band gap of annealed sample than the as-deposited one and it was decreased with sample thickness. The resistivity measurement confirmed resistivity decreament with temperature. Furthermore, by investigating the magnetic properties, room temperature ferromagnetism was observed.

Dry season irrigated rice (boro) can be transplanted into non-puddled soil when it follows a mustard crop in Bangladesh. However, the options for non-puddled transplanting, including reduced tillage (RT) or zero tillage (ZT) with manual or mechanised transplanting have not been evaluated in farmers' fields. Therefore, two on-farm experiments were conducted over three years to compare two transplanting methods (manual – Man, mechanical – Mech) and three tillage methods (reduced tillage - RT, zero tillage - ZT, and conventional tillage - CT (puddling)). For both transplanting methods, grain yield with CT and RT was similar. However, there was a slight (3–4%) but significant decline in grain yield with ZT in three out of four instances. Total irrigation input increased with decrease in tillage, by around 100–150 mm in RT compared with CT, and by 200–300 mm or 25–30% in ZT compared with CT. Grain yield and gross margin of mechanically transplanted rice with CT, RT and ZT were higher than or similar to that for manually transplanted rice, while the labour requirement for mechanical transplanting was 5% of that for manual transplanting. Furthermore, mechanical transplanting provides the opportunity to advance crop establishment.

The nanostructured ZnO thin films have been fabricated on seedless SnO2: In (ITO) substrate by using an inexpensive and uncovered hydrothermal method. These prepared ZnO films are used as electron transporting materials to fabricate the perovskite solar cells (PeSCs). The performance of PeSC has been varied with ZnO-deposition temperatures ranges from 55 to 105 °C. The ZnO films show the high crystalline wurtzite structure. The whole surface of ZnO films fabricated at the higher deposition temperatures has covered with the hexagonal nanorods/nanotubes-like structures. The maximum efficiency of 4.55% is obtained for PeSC with ZnO films prepared at 85 °C. The photocurrent increases from 8.5 to 13.9 mA/cm2 with the ZnO-deposition temperature increases from 55 to 105 °C. The PeSC with ZnO films prepared at 95 and 105 °C shows the lower efficiency than the PeSC with ZnO-85 °C, which may be caused due to the large series and shunt resistance as well as the carrier leakage in PeSCs. The surface morphological, structural, and optical properties of ZnO electrodes fabricated at various deposition temperatures have been correlated with the photovoltaic performances of PeSC prepared by these ZnO electrodes.

Titanium dioxide (TiO2) films have been deposited on indium-doped tin oxide (ITO) glass substrate by electron-beam evaporation (EBE) system at room temperature (RT, 25 °C). After that, prepared TiO2 films are annealed at different temperatures of 150, 250, 350, 400, 450 and 500 °C. The novelty of this work is to investigate the effect of annealing temperature on the photovoltaic performances of perovskite solar cell (PeSC) with these annealed TiO2/ITO structures. For the fabrication of PeSC, perovskite (PRV) layer has been fabricated on TiO2 films by two-steps method. The TiO2 film prepared at RT shows the amorphous structure with the compact surface and Ti3+ state. Interestingly, crystallinity and porosity of the TiO2 films increase with the increase of annealing temperature. The TiO2 films annealed at 500 °C have shown high crystallinity with Ti4+ state and mixed phases (anatase and rutile). The grain boundary becomes visible, the size and porosity of TiO2 films increase with the increase of annealing temperature. The PeSC with TiO2 films prepared at RT shows the highest photoelectric conversion efficiency (PCE) of 6.15% with maximum photocurrent (14.37 mA/cm2) than the other PeSCs with annealed TiO2 films. The PCE, photocurrent and fill factor of PeSC decrease but the photovoltage increases with increase in annealing temperature, which may be caused by carrier leakage between PRV layer and ITO substrate, high series and low shunt resistances, and also the enhanced sheet resistance of ITO substrate.

Previous studies showed that prolonged exposure to fluoride (F-) and aluminum (Al3+) ions is associated with numerous diseases including neurological disorders. They don't have any known biological function. But they can bind with proteins that interact with ions similar to them. Such unwanted interactions affect the normal biological function of the target proteins, as well as their downstream protein-protein interactions. Several studies show the detrimental effects posed by them including Alzheimer's disease. However, their target proteins have never been reported. Here, we have screened for the human protein targets subjected to F- and Al3+ interactions by using data-driven prediction tools. We have identified 20 different proteins that directly bind with them (10 interact with fluoride and 10 with aluminum). In addition, protein-protein interaction has been explored to find the proteins that indirectly interact with F- and Al3+. We have found 86 indirect targets for F- and 90 for Al3+. Furthermore, 19 common protein targets have been identified, including proteins (9 out of 19) associated with neurodegenerative disorders. However, wet lab experiments are beyond our scopes to validate the binding networks. Additional studies must be warranted.

Cd-free ZnCuInS/ZnS quantum dot-based light-emitting diodes (QLEDs) were fabricated using metallic sputtered ZnO. The undoped and metallic ZnO film was prepared with substrate heating to enhance the electronics properties of the oxide layer. The semiconductor properties of the ZnO layer were examined by using Hall effect measurements. The structural and morphological properties were observed using x-ray diffraction analysis and field emission scanning electron microscopy. After fabricating the QLED devices, its performances were investigated under DC electrical measurement system and compared with the preparation conditions of the ZnO films. The power efficiency of 11.6 lm/W, current efficiency of 14.1 cd/A, and external quantum efficiency (EQE) of 7.5% were achieved, where the ZnO film was prepared at the substrate temperature of 150 °C, and the Hall mobility of 23.4 cm2/Vs, carrier density of 4.1 × 1020 cm−3 was observed accordingly.

A database of lightning-related deaths and injuries in Bangladesh was developed from 1990 to mid-2016 from a variety of sources that contains a total of 5468 casualties, composed of 3086 fatalities and 2382 injuries. Spatial, temporal, and demographic aspects of these lightning casualties are evaluated in order to aid relevant entities in effective management of lightning-related meteorological hazards. The annual averages for Bangladesh are 114 fatalities and 89 injuries over the entire period. Weighting by population reveals a fatality rate of 0.92 per million people per year and an injury rate of 0.71. In contrast, the latest 6 years have a fatality rate of 1.6 and injury rate of 1.4. The rural portion of lightning fatalities is 93%. Most fatalities occurred between early morning (0600 LST) and early evening (2000). Through the year, more fatalities occur during the premonsoon season of March through May than during the monsoon season (June–September). The interannual time series of fatalities indicates an increase since the late 2000s, which is a result of greatly improved communications leading to better media reporting of lightning casualties. Bangladesh has also become much more populous in recent years. As a result, the most recent 6 years have 251 fatalities per year, which may be considered as the current estimate. The majority of lightning-related deaths occurred to males. Farming is the major activity at the time of lightning fatalities followed by being inside a dwelling and returning home or walking around homesteads/courtyards.

Highly aligned titania (TiO 2 ) nanotube (NT) arrays have been grown on titanium sheet by using a self organized anodic oxidation method at different potentials (34–74 V) in a NH 4 F and ethylene glycol based electrolyte. Two sets of TiO 2 NT arrays have been fabricated with and without using cooling systems. Without cooling system, the solution temperature is increased from 25 °C (room temperature) to 63 °C with increase of anodization potential from 34 to 74 V. The temperature has been maintained to 25 °C by using water based cooling system. In both sets of samples, the pore diameter of TiO 2 NT arrays increases with increase of anodization potential. The maximum pore diameter has been (outer: 224 nm, inner: 172 nm) achieved with TiO 2 NT arrays (at 74 V) without using cooling system. The photocatalytic activity of the TiO 2 NT arrays is evaluated by the decomposition of methanol by the use of Fourier transform infrared spectrophotometer. The TiO 2 NT (at 44 V) sample has been fabricated without using cooling system, which shows the higher photocatalytic activity than the sample at other potentials. Using cooling system, the TiO 2 NT (at 54 V) sample shows the higher photo-decomposing property than the sample at other potentials. The TiO 2 NT (at 54 V) sample with cooling system shows the higher rate (photocatalytic activity) constant ( k = 0.0216) than the TiO 2 NT (at 44 V) sample without using cooling system ( k = 0.0186). The photocatalytic activity has been correlated with the nanostructural variation of TiO 2 NT arrays at different potentials without (self-grown solution temperature) and with water based cooling systems.

In this paper, the structural, optical and photoluminescence (PL) features of the spray deposited Ba:SnO2 thin films with varying thickness have been investigated. X-ray diffraction analysis showed that Ba:SnO2 thin films have a polycrystalline tetragonal rutile structure and nanometric dimensions. The preferred directional growth of nanocrystalline was along direction. The crystallite size of the samples was calculated using the Debye-Scherrer equation. With an increase in film thickness, the crystallite size decreased from 11.72 to 5.27 nm, while crystal imperfections, viz. lattice strain, degree of lattice distortion and dislocation density increased. The influence of film thickness on the transmittance and reflectance was investigated by using UV-Vis spectral data. The average visible transmittance of Ba:SnO2 nanocrystalline declined from 85 to 79% at 550 nm with an increase in film thickness. Ba:SnO2 nanocrystalline exhibited a slight red-shift in the absorption edge and the optical band gap was found to decrease in the range 3.94 to 3.64 eV. Near band-edge UV emissions band at ~ 402 nm were observed in the PL spectra which are attributed to the defect levels originating from the oxygen vacancies.

Alternative splicing evolved as a very efficient way to generate proteome diversity and to regulate cell homeostasis from a limited number of genes. Moreover, changes in the relative amounts of different splice variants derived from the same pre-mRNA are a hallmark in cancer, and aberrant expression of alternatively spliced mRNAs has been linked to cancer initiation and progression. Therefore, splice variants are critical tools to assess disease progression and clinical prognosis, and hold great promise as potential targets for therapeutic intervention. In order to understand the role that such splice variants play in cancer, it is vital to be able to accurately quantify their expression levels in different cell types and organs, both in normal conditions and in disease. In this chapter we describe a protocol to efficiently detect, analyze, and quantify alternative splicing patterns of immune mediators such as chemokines, cytokine and their receptors and ligands in cancer by quantitative PCR.

Background: To analyze our recent experiences at the National Institute of Cardiovascular Diseases (NICVD) with the management of vascular Thoracic Outlet Syndrome (TOS).Methods: Retrospective review identified 51 patients (age range 23 to 67 years) with vascular TOS, among them 47 patients with arterial type TOS underwent surgical treatment from January 2012 to December 2015. Evaluation included clinical assessment plus duplex ultrasonography and contrast arteriography and outcome of treatment.Results: In 44 (94%) patients, surgery was successful in relieving the ischemic symptoms. Major amputations could be avoided in 21 of the 28 patients presenting with gangrene. Recurrent thrombo-embolism of the distal arterial tree was found in 5 patients requiring repeat embolectomy. At one year follow-up, 73% of the patients remained free from ischemic upper limb symptoms.Conclusions: Though relatively uncommon, arterial TOS is a potentially limb threatening condition. Early detection of the anatomical abnormality with its surgical correction is required to avoid major complications.Cardiovasc. j. 2018; 11(1): 50-52

Background: Contaminated handmade street foods are often claimed to occur food-borne diseases, especially in developing countries. Therefore, considering the public health issue, this study was conducted to assess the microbial contamination of handmade sauce used by street food vendors in Jashore, Bangladesh. Methods: A total of 30 samples of Plum Sauce (PS) and Tomato Sauce (TS) were collected from Jashore district, Bangladesh. The quantitative microbial tests were done by dilution plate technique. Identification of particular bacterial group or species was performed using selective media. All the data related to microbial count were subjected to ANOVA test using SPSS version 21.0. Results: All the sauce samples contained viable Enterobacteriaceae cells; whereas 80% and 83.33% of the total samples were found to be contaminated with Salmonella spp. and Escherichia coli, respectively. Total viable bacterial cells found in the samples ranged from 1.2×103 to 4.2×109 Colony Forming Unit (CFU)/g. In addition, total Enterobacteriaceae and E. coli counts ranged from 30 to 2.0×107 and from 0 to 7.0×105 CFU/g, respectively. Although PS samples contained a higher amount of Enterobacteriaceae and E. coli compared to TS, no significant difference (p>0.05) was found. Conclusion: The consumption of street foods is of great concern in Bangladesh. Making the vendors aware of sanitary practices is too crucial that could be achieved through training of the vendors at the root level of the country. Furthermore, it is necessary to monitor the street foods frequently by the national authorities.

We have investigated a perovskite photo-sensors with electron-beam evaporated titanium dioxide (TiO 2 ) film as an electron transport buffer layer. The TiO 2 films have been deposited on indium-doped tin oxide (ITO) glass substrate at room temperature. Then, prepared TiO 2 films are annealed at different temperatures of between room temperature and 500°C. Device structure is ITO/TiO 2 /Perovskite layer/2,2,7,7-tetrakis (N,N-di-p-methoxyphenylamine)-9,9-spirobifluorene/Au. Before and after annealing process, TiO 2 films have changed from an amorphous to crystalline structure mixed with anatase and rutile phases. For a sensing characteristics, a ratio of photo- and dark-current was 1.1×103 without annealing condition. It is assumed that a flat device structure and a larger photocurrent under illumination are effective to reduce carrier generation site.

In this work, a digitalized sol-gel system is prepared for fabrication of efficient thin films. The proposed system of this paper offers dipping and withdrawing of a substrate with precise timing and has an extra feature of holding multiple beakers having multiple solutions for fabricating complex layered films. This system also provides rotation of the beakers containing required solution to be deposited on a substrate with the help of pressing only a button. Duration of dipping time of the substrate can also be set using this system. In short this digitalized system offers multiple features of thin film fabrication using sol-gel technique with high percentage of minimizing defects.