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Blooms of Microcystis are common in fish ponds in Bangladesh which vary distinctly with season to season. A study on the seasonal changes of Microcystis and Anabaena was carried out over a period of 12 months from March 2021 to February 2022 in two rural fish ponds to see the effect of environmental factors on the seasonal dynamics of these two species. Cyanobacterial community comprised of seven genera and 15 species of which Microcystis was found to be the most dominant genus. Overabundance of Microcyctis may suppress the growth of Anabaena and other microalgal species. In both ponds, Microcyctis was found to be the dominant during the summer and the spring, whereas Anabaena was only characterized in summer. Moderately higher temperature, nitrate–nitrogen, and phosphate–phosphorus enrichment increased the biomass of both Microcystis and Anabaena. Microcystin was found in all the seasons with the highest quantity in summer in the cyanobacteria samples collected from both of the ponds. The highest concentrations of MCs were 22 and 65 μg/L of the sampled water during the peak bloom period of blue‐green algae in pond 1 and pond 2, respectively. The high concentration of microcystin in water seems to be a pernicious warning for aquatic organisms as well as human health. Further studies in detail on the relationship between microcystin and cyanobacterial growth under different environmental factors seem to be necessary. [ABSTRACT FROM AUTHOR]

Growing microalgae on vegetable waste (rotten potatoes) media is not only a plausible technique to replace expensive commercial media but also a way of reducing feed costs for rearing zooplankton and fish larvae in aquaculture. As a way of starting an inevitable step up, Monoraphidium littorale was grown in 25% (T1), 50% (T2), and 75% (T3) of digested rotten potato supernatant (DRPS) and at the same time in Bold Basal Medium (BBM) as a control (T4) for 16 days. The highest cell density of M. littorale was recorded in T1, followed by T4, T2, and T3. A similar increasing trend of chlorophyll-a and optical density was also observed during the experimental period. The study also ascertained T1 as a potential growth medium where M. littorale showed superior biomass production which was significantly higher (P < 0.05) than other treatments. It was also worth mentioning that the highest (P < 0.05) protein content was determined in T1 at the end of the cultivation time. Similarly, a highly significant difference (P < 0.05) was also found in the lipid content of the microalgae grown in T1 and T4. Furthermore, the morphology of the cells of M. littorale was found to be strongly affected by the DRPS concentrations and BBM. Thus, the lower concentration of the DRPS served as the best medium for enhancing the growth and biomass of M. littorale. Consequently, to expedite the sustainable progression of microalgal production, cost-effective culture techniques by using different wastes may be adopted. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WOx) thin films were synthesized through the RF magnetron sputtering method by varying the sputtering power from 30 W to 80 W. Different investigations have been conducted to evaluate the variation in different morphological, optical, and dielectric properties with the sputtering power and prove the possibility of using WOx in optoelectronic applications. An Energy Dispersive X-ray (EDX), stylus profilometer, and atomic force microscope (AFM) have been used to investigate the dependency of morphological properties on sputtering power. Transmittance, absorbance, and reflectance of the films, investigated by Ultraviolet-Visible (UV-Vis) spectroscopy, have allowed for further determination of some necessary parameters, such as absorption coefficient, penetration depth, optical band energy gap, refractive index, extinction coefficient, dielectric parameters, a few types of loss parameters, etc. Variations in these parameters with the incident light spectrum have been closely analyzed. Some important parameters such as transmittance (above 80%), optical band energy gap (~3.7 eV), and refractive index (~2) ensure that as-grown WOx films can be used in some optoelectronic applications, mainly in photovoltaic research. Furthermore, strong dependencies of all evaluated parameters on the sputtering power were found, which are to be of great use for developing the films with the required properties. [ABSTRACT FROM AUTHOR]

This research analyzes journalists' and audiences' responses to a critical incident: the coverage of Kobe Bryant's death, including whether it included accusations against Bryant, and of the Washington Post's brief suspension of reporter Felicia Sonmez, who, at his death, retweeted an old storey about rape charges filed against Bryant. Findings are that journalists focused on the complexity of Bryant's legacy and emphasized the journalistic values of professionalism and truth. Moreover, while journalists engaged in some boundary setting, this research suggests the value of seeing audiences as press critics not unlike professional journalists. Audiences acknowledged and endorsed journalistic principles but noted the importance of social norms; their expectations for good journalism suggest ways to rebuild trust in journalism. [ABSTRACT FROM AUTHOR]

In this paper, a physically based two-dimensional analytical model of potential profile is proposed for both symmetric and asymmetric p-type-doped Double Gate Junctionless Field Effect Transistors (DG JLFETs). The proposed model keeps its validity in the subthreshold region. In order to establish the model, 2-D Poisson's equation is solved in the channel region while assuming cubic potential distribution along the channel region. We also propose a 2-D analytical model of symmetric Double Gate Stack-Oxide Junctionless Field Effect Transistors (DGS JLFETs). In order to check out the validity of our proposed model, we have used SILVACO ATLAS simulator. Comparison of potential distribution is made between different structures. Between symmetric and asymmetric structures, symmetric structure shows better potential profile as they have shown higher potential distribution in channel region. But when DG JLFET is compared with DGS JLFET, we find better potential profile distribution in DGS JLFET. Important performance parameters like Ion/Ioff ratio, SS, DIBL, Threshold Voltage, I–V characteristics for different structures are found out and compared among them. Asymmetric structure with same electrode materials in both gates but having lower bottom gate oxide thickness showed better performances like higher Ion/Ioff ratio, lower SS, less DIBL compared to other DG JLFETs with and without stack oxide. [ABSTRACT FROM AUTHOR]

This study examines the online niches of English-language newspapers in Bangladesh by analyzing stories and user engagement on the Facebook pages of five highest circulated newspapers. Based on the theory of the niche, this study analyzed data on 17,687 Facebook posts downloaded programmatically. Results indicate that users read these newspapers for in-depth news stories and features on diplomacy, national security, lifestyle, science, technology, and international events. The study identified a gap between what these newspapers offer and what their users want. [ABSTRACT FROM AUTHOR]

Objective: The objective of this research work was to find out the prevalence of clinically occurring diseases and the disorders in cattle and goats at the Sylhet Agricultural University area, Sylhet during January to December 2013. Materials and methods: This clinical study was carried out on 775 clinical cases (553 cattle and 222 goats) based on the general, clinical, physical and microscopical examination along with common laboratory techniques. Results: The clinically observed cases in cattle were (i) gyneco-obstetrical (15.37%; n=85/553; P=0.038), (ii) metabolic and nutritional (9.94%; n=55/553; P=0.245), (iii) bacterial and viral (26.22%; n=145/553; P=<0.001), (iv) parasitic (26.58%; n=147/553; P=<0.001), and (v) digestive diseases (21.88%; n=121/553; P=0.008). Similarly, in goats, the prevalences were found to be 14.41 (n=32/222; P=0.041), 15.76 (n=35/222; P=0.078), 30.63 (n=68/222; P=0.001), 23.87 (n=53/222; P=0.020), and 15.31% (n=34/222; P=0.069), respectively. Conclusion: This research work is a groundwork which may facilitate the potential researchers to investigate the details possessions for extensive therapeutic exercises in Bangladesh particularly in Sylhet region for designing the control strategies and conducting the treatment of infection and disorders in cattle and goats. [ABSTRACT FROM AUTHOR]

This study investigates the influence of hydrostatic pressure on structural, electronic, mechanical and optical properties of Sr3PX3 (X = Cl and Br) compounds, by using the first-principles density functional theory (DFT) within the pressure range of 0–30 GPa with a span of 10 GPa. For Sr₃PCl₃ and Sr3PBr3, the dynamical stability is confirmed by the fact that the phonon dispersion curves do not contain imaginary modes. Pressure-induced band gap alterations in Sr3PCl3 and Sr3PBr3 reveal semiconducting behavior: GGA measurements show a decrease from 1.70 eV and 1.55 eV at ambient pressure to 0.22 eV and 0.21 eV at 30 GPa; TB-mBJ results show a decrease from 2.73 eV and 2.40 to 1.07 eV and 0.92 eV. This supports their inverse relationship with pressure. The values of Debye and melting temperatures support their high-temperature applications. Effective mass also shows an inverse relationship with induced pressure. The bond length, lattice parameters, and cell volume reduces with pressure. They exhibit ductility, which is further enhanced by the applied pressure. These materials emerge as promising candidates for flexible optoelectronic devices. Optical properties like absorption coefficients, reflectivity, and dielectric functions were observed and found to be significantly influenced by applied pressure. The absorption spectra exhibit a significant redshift with increasing pressure, indicating enhanced potential for optoelectronic applications. Our detailed investigation sheds light on the tunability of Sr3PX3 (X = Cl and Br) properties under pressure, showcasing their potential for cutting-edge applications in optoelectronics and photovoltaics. [ABSTRACT FROM AUTHOR]

Worldwide the quality and high price of fish feed are an important issue for sustainable aquaculture that warranted the development of low-cost culture systems utilizing natural resources. An experiment was conducted in a tidally inundated wetland in the coastal region of Bangladesh utilizing naturally grown floating grass, Hygroryza aristata as a fish feed. The experiment was conducted under three treatments each with three replications for one year. In treatment one, the grass was planted and grown on the bottom soil before stocking of fish (T1; in-situ grass); in treatment two, the grass grown elsewhere was collected and supplied as fish feed in raw condition (T2; ex-situ grass); and in treatment three, the fishes were fed with commercial floating fish feed (T3; control). Grass carp, common carp, black carp and tilapia were reared at the ratio of 6:1:1:2 with a total stocking density of 12,350 fish ha−1. The survival rate, growth (weight gain, % weight gain and specific growth rate, SGR), production and cost and benefit of fish production were calculated. The survival of the fish varied from 76.00% to 85.14% irrespective of species. The weight gain, % weight gain and SGR of grass carp and common carp were highest in in-situ grass, followed by ex-situ grass and control, whereas tilapia showed the highest growth in control, followed by in-situ and ex-situ grass. The total production of fish was highest in in-situ grass (9060.70 kg ha−1 year−1), followed by control (8469.70 kg ha−1 year−1) and ex-situ grass (8001.23 kg ha−1 year−1). The net economic benefit and benefit-cost ratio were also highest in in-situ grass (US$ 17,994.96 ha−1 and 4.52), followed by ex-situ grass (US$ 14,278.30 ha−1 and 2.78) and control (US$ 4818.63 ha−1 and 0.32). The present findings indicate that coastal wetlands of Bangladesh can be used for commercial aquaculture using the H. aristata floating grass as fish feed, which may play an important role in the livelihood development of the people living in the coastal areas of the country. • Coastal tidal wetlands can be used for commercial aquaculture using Hygroryza aristata floating grass as fish feed. • H. aristata floating grass plantation as feed before fish stocking reduced production cost 3.82 times and achieved BCR of 4.52. • H. aristata floating grass may be an alternative important plant protein source in the feed industry formulating fish feed in near future. [ABSTRACT FROM AUTHOR]

In Bangladesh the exposure of millions of inhabitants to water from (shallow) tube wells contaminated with high geogenic loads of arsenic is a major concern. As an alternative to the costly drilling of deep wells, the return to the use of surface water as a source of drinking water is considered. In addition to the well-known hazards of water borne infectious diseases associated with the use of surface water, recently the potential public health implications of toxic cyanobacteria have been recognized. As a first step towards a risk assessment for cyanotoxins in Bangladesh surface waters, seston samples of 79 ponds were analysed in late summer 2002 for the presence of cyanobacteria and microcystins (MCYST), the most frequently detected cyanobacterial toxins worldwide. Microcystins could be detected in 39 ponds, mostly together with varying abundance of potentially microcystin-producing genera such as Microcystis, Planktothrix and Anabaena. Total microcystin concentrations ranged between <0.1 and > 1,000 microg l(-1), and more than half of the positive samples contained high concentrations of more than 10 microg l(-1). The results clearly show that concentrations of microcystins well above the provisional WHO guideline value of 1 microg l(-1) MCYST-LR can be frequently detected in Bangladesh ponds. Thus, an increasing use of surface water for human consumption introduces a risk of replacing one health hazard by another and therefore needs to be accompanied by cyanotoxin hazard assessments.

In the present study tentative link has been established between H+ -efflux and effect of NO in presence of various nutrients (glucose, 2-deoxy-D-glucose, xylose, proline, glutamic acid and lysine) in C. albicans using sodium nitroprusside (SNP) as a potent source of NO. It was observed that there was a decreasing trend in pH with time, in control, while SNP treated cells showed an initial decline in pH for 10-15 min, followed by an increase in pH up to 30 min. In presence of glucose there was an enhancement in H+ -efflux by 9-fold whereas proline, glutamic acid and lysine showed enhancement by 3, 6 and 1.5-fold respectively. Similar trends in increase in pH after 15 min in SNP treated cells of Candida was observed in presence of all nutrients used. It was demonstrated for the first time that H+ -ATPase of C. albicans was affected by NO.