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The two most prominent areas of nanotechnology and nanoscience are environmental remediation and biomedical applications, which has a strong need to develop cleaner and more eco-friendly methods for preparing functional nanomaterials. This involves incorporating non-toxic chemicals and reagents for converting metal cations into metal or metal oxide nanoparticles (NPs), using readily available plant reagents and microbes as redox mediators. The extracts of these plants and microbes contain varying amounts of phytochemicals and metabolites that act as redox mediators and capping agents to stabilize biosynthesized NPs. Considering these natural reagents for forming metal/metal oxide NPs, the present work aims to provide a complete review of the green fabrication of nickel oxide (NiO) NPs using extracts from various plant and microbial sources. In addition, the performance of various biosynthesized NiO NPs and their potential uses in biological applications are discussed.

This work investigates the hybrid nanocomposites manufactured by direct mixing by dispersing varying weight percentages (wt.%) of graphene nanoparticles (GNPs) and Al2O3 NPs in epoxy resin. Their properties are then obtained using various mechanical (tensile, flexural, impact, and hardness) and thermal (thermogravimetric) analyses. Furthermore, their microstructure and functional groups are studied by SEM and FTIR, respectively. The hybrid nanocomposite, which contains 1.5 wt.% GNPs and 8.5 wt.% Al2O3 NPs, has excellent mechanical properties. Compared to a composite without GNPs, the tensile strength, flexural strength, impact strength, and shore D hardness improve by 95.12, 90.01, 171.43, and 19.75%, respectively. It is also found that hybrid nanocomposite exhibits enhanced thermal stability as GNPs increase, particularly at lower wt.% of Al2O3. The SEM of tensile fractured specimens of GNPs/Al2O3 epoxy hybrid nanocomposites reveals prominent failure mechanisms, including agglomeration of GNPs and debonding between the GNPs/Al2O3 and epoxy. The FTIR spectroscopy analysis reveals distinctive spectral peaks indicating successful incorporation of Al2O3 and GNPs into the epoxy‐based composite, with observed peaks corresponding to functional groups and bonds characteristic of each component. These findings suggest that the manufactured nanocomposite holds promise as a component in structural applications, particularly in automobiles, aerospace components, and sports equipment. [ABSTRACT FROM AUTHOR]

This study investigates the structural, mechanical, optical, thermal, and electronic properties of the ionic semiconducting materials XZrS3 (X = Ca, Ba) within the framework of density functional theory (DFT). Here, the elastic constants, modulus (bulk, shear, Young's), ratios (Pugh, Poisson) and elastic anisotropy for XZrS3 (X = Ca, Ba) are studied. Furthermore, the electronic, optical, and thermal properties for XZrS3 (X = Ca, Ba) are regenerated and designed using the values obtained with Cambridge Serial Total Energy Package (CASTEP) software. The calculated lattice parameters show excellent agreement with theoretical and experimental values. The elastic stiffness constants confirm the mechanical stability of both compounds. Although XZrS3 (X = Ca, Ba) is elastically anisotropic, it has little optical anisotropy. The electronic band structures of the material exhibit direct-bandgap semiconducting behavior, with values of 1.3 eV (CaZrS3) and 1.1 eV (BaZrS3) using the generalized gradient approximation (GGA), respectively, which is ideal for solar cell (0.9–1.56 eV) and optoelectronic device applications. Bandgap values of 1.9 eV and 1.6 eV are found for CaZrS3 and BaZrS3, respectively, using the Heyd–Scuseria–Ernzerhof HSE06 functional, which is consistent with previous theoretical and experimental bandgap results. The optical properties including dielectric function, refractive index, absorption coefficient, reflectivity, and loss function are characterized using the GGA of Perdew–Burke–Ernzerhof (GGA-PBE) and HSE06 methods and are discussed in detail. Because of the relatively low Debye temperature (D), thermal conductivity of the lattice (kph), and minimum thermal conductivity (Kmin), the studied materials can be used as thermal barrier coating (TBC) materials. The capacity of heat, Debye temperature, and thermal coefficient of expansion are all computed. [ABSTRACT FROM AUTHOR]

Seismic ambient noise (SAN) energy can potentially blur regional and teleseismic arrivals as well as various microearthquakes at specific frequencies. Therefore, quantification of the SAN energy level in a region is required to optimize seismic station distribution for seismological investigations. Moreover, evaluation of station performance and noise source is possible from observation of SAN energy levels. The SAN energy distribution from seismic stations in the Bengal Basin (BB), Bangladesh has not yet been estimated. At the same time, this tectonically active and complex region is less studied using seismic methods. This study aims to quantify SAN energy and characterize its diurnal variation along with evaluating station performance at 11 seismic stations, which were temporarily installed in the deeper portion of the BB. Herein, the daily SAN energy level was determined within the period range of 0.02-30 s by estimating the power spectral density (PSD) of seismic data for 7 continuous days. SAN energy and its variation over time were observed using the probability density functions (PDFs) of PSDs and spectrograms, respectively. The sources of SAN energies at different period bands were also investigated by comparing the PSDs with daily variations in human activities, nearby noise sources, local meteorological factors (i.e., air temperature and precipitation), and sea level height. The insights from this study could be useful for the future deployment of seismic networks as well as seismological studies in the BB. [ABSTRACT FROM AUTHOR]

Indigenous sheep are highly adaptable and widely distributed in different regions of Bangladesh. They are famous for their tolerance to harsh environmental conditions, low demand for feed, and disease resistance with minimum or no housing and management facilities. Ample indiscriminate research reports and case studies on the native sheep of Bangladesh have been published. Nonetheless, a comprehensive review of reproductive and productive performances, as well as their various morphometric physiognomies and climate resilience capabilities, is lacking. This review was designed to explore and summarize the available research reports on indigenous sheep to highlight the gaps and provide an updated database for the future research plan for sustainable native sheep production in Bangladesh. It covers studies on sheep biodiversity, their adaptability to the local environment, morphometric features, feeding and nutrition, reproduction and production performances, diseases and health management, and the problems and prospects of sheep farming in Bangladesh. Due to the increased demand for animal protein, especially red meat, the scope of sheep farming increases along with that of other large and small ruminants. The vital constraints of sheep production in Bangladesh include insufficient feed and fodder supply with its high prices, higher disease occurrence with low or no management practices, kid mortality, and a poor marketing channel with the lower popularity of sheep meat than goat meat. Future research would be a prerequisite to measuring the impact of native sheep on household economies and food security during the year, evaluating the other challenges, and finding out the possible interventions in the fields of nutrition, reproduction, and health management. [ABSTRACT FROM AUTHOR]

Background & Objective: Vascular Endothelial Growth Factor (VEGF) is one of the newer molecular markers that acts as a central mediator of tumor angiogenesis and is essential for tumor growth, progression, and metastasis. So anti-angiogenic drugs can be used as anticancer therapy. Treatments with anti-VEGF (Bevacizumab) therapy have been proved to improve relapse-free survival in many tumors. Urinary bladder tumor has become emerging cancer globally among elderly individuals. So, the identification and development of novel biomarkers for effective treatment of urinary bladder carcinoma is essential. The present study aimed to investigate the immunohistochemical expression of VEGF in urothelial carcinoma of urinary bladder and to assess its association with tumor grade and muscle invasiveness. Methods: This cross-sectional study was conducted in the Department of Pathology, Chittagong Medical College, Chattogram from September 2018 to August 2020. Fifty-six formalin-fixed paraffin-embedded tissue blocks of urinary bladder carcinoma were prepared for both histopathological and immunohistochemical examination. Each slide was evaluated by at least two pathologists. Results: Weak to strong positive expression of VEGF were observed in 52 cases (92.86%). The proportion of tumors positive for VEGF expression was higher among patients with high grade and non-muscle invasive bladder carcinoma. Conclusion: We found that VEGF expression has a significant association with tumor grade and an inverse association with muscle invasion. These findings may be useful for selecting the subset of patients likely to respond to anti-VEGF targeted therapy. [ABSTRACT FROM AUTHOR]

The rapid urbanization and industrialization along with the expansion of cities in developing countries like Bangladesh converting vegetation and bare land into built-up area that remarkably boost up the land surface temperature (LST). This study has been conducted for correlating and monitoring the changes of landuse–landcover change (LULC) and LST of rapidly expanding Chittagong metropolitan area from 1989 to 2018 utilizing four Landsat satellite images (TM, ETM+, OLI, and TIRS). The Present study combines the techniques of remote sensing and geographic information system (GIS) to find out the spatial variation of LST and identify its relationship with LULC. Supervised classification technique has been employed in ERDAS IMAGINE 14.0 software to retrieve LULC data. The images of the study area were categorized into four different classes namely vegetation, urban structures, bared lands and water bodies. LSTs were estimated using the single thermal infrared band of Landsat TM, ETM+, and the band 10 and 11 of the TIRS sensor's image for the split-window algorithm method. Concerning the relationship between LULC and LST, it has been found that vegetation and water bodies shows lowest LST while bared lands and urban structures indicates highest LST. LULC analysis shows a dramatic increase in urban structures (from 20.83 to 58.93%), decrease in vegetation (from 56.54 to 20.24%) and bared lands (from 16.67 to 11.90%) and a further small increase in water bodies after the 80s, because of digging new ponds. LST in the study area has been increasing as high-temperature LU types have increased and low temperature LU types have decreased. Consequently, the mean annual temperature showed 6.5 °C increase, the minimum and maximum LST increased by 9 °C and 4 °C throughout the study period. The highest maximum and lowest minimum LST has found 40 °C during the years of 2010 to 2018 and 15 °C in the year of 1989, respectively. The study will assist the decision-maker to understand the impacts of unplanned urbanization for future city planning and urban management. [ABSTRACT FROM AUTHOR]