Comparative pathogenicity of a genotype XXI.1.2 pigeon Newcastle disease virus isolate in pigeons and chickens.

Here, we performed molecular and pathogenic characterization of a Newcastle disease virus (NDV) isolate from pigeons in Bangladesh. Molecular phylogenetic analysis based on the complete fusion gene sequences classified the three study isolates into genotype XXI (sub-genotype XXI.1.2) together with recent NDV isolates obtained from pigeons in Pakistan (2014-2018). The Bayesian Markov Chain Monte Carlo analysis revealed that the ancestor of Bangladeshi pigeon NDVs and the viruses from sub-genotype XXI.1.2 existed in the late 1990s. Pathogenicity testing using mean embryo death time pathotyped the viruses as mesogenic, while all isolates carried multiple basic amino acid residues at the fusion protein cleavage site. Experimental infection of chickens and pigeons revealed no or minimum clinical signs in chickens, while a relatively high morbidity (70%) and mortality (60%) were observed in pigeons. The infected pigeons showed extensive and systemic lesions including hemorrhagic and/or vascular changes in the conjunctiva, respiratory and digestive system and brain, and atrophy in the spleen, while only mild congestion in the lungs was noticed in the inoculated chickens. Histologically, consolidation in the lungs with collapsed alveoli and edema around the blood vessels, hemorrhages in the trachea, severe hemorrhages and congestion, focal aggregation of mononuclear cells, and single hepatocellular necrosis in the liver, severe congestion, multifocal tubular degeneration, and necrosis, as well as mononuclear cell infiltration in the renal parenchyma, encephalomalacia with severe neuronal necrosis with neuronophagia were noticed in the brain in infected pigeons. In contrast, only slight congestion was found in lungs of the infected chickens. qRT-PCR revealed the replication of the virus in both pigeons and chickens; however, higher viral RNA loads were observed in oropharyngeal and cloacal swabs, respiratory tissues, and spleen of infected pigeons than the chickens. In conclusion, genotype XXI.1.2 NDVs are circulating in the pigeon population of Bangladesh since 1990s, produce high mortality in pigeons with pneumonia, hepatocellular necrosis, renal tubular degeneration, and neuronal necrosis in pigeons, and may infect chickens without overt signs of clinical disease and are likely to shed viruses via the oral or cloacal routes.

Comparative pathogenicity of infectious bursal disease viruses of three different genotypes.

Infectious bursal disease (IBD) is a highly immunosuppressive and often fatal viral disease of young chickens. The causal agent IBD virus (IBDV) is an avian Birnavirus having two genome segments that have evolved independently and contributed to the emergence of many genotypes with different pathogenic profile. The present study aimed at genetic and pathogenic characterization of IBDVs from Bangladesh. We performed phylogenetic analysis of 15 IBDV isolates recovered from field outbreaks in chickens during 2020-2021 and compared the pathogenicity of three selected isolates belonging to different genotypes on experimental infection in chickens. Out of 15 isolates, one was the typical vvIBDV of genotype A3B2, 13 were reassortant vvIBDV of genotype A3B3 having very virulent-like segment A and early Australian-like segment B, and the remaining one isolate was a classical virulent IBDV of A1aB1 genotype. A few amino acid substitutions were observed between the genotypes in four putative antigenic sites on VP2. In a comparative pathogenicity study, the typical vvIBDV isolate BD-25(A3B2) appeared to be the most virulent with 100% morbidity and 90% mortality, followed by the segment-reassortant vvIBDV isolate BD-28(A3B3) with 50% morbidity and 30% mortality. However, the gross and histopathological lesions in the bursa of Fabricius were similar. The classical virulent isolate BD-26(A1aB1) did not cause any clinical disease. In conclusion, three genotypes of IBDV are co-circulating in poultry of Bangladesh and the typical vvIBDV of A3B2 genotype was more virulent than the reassortant vvIBDV of A3B3 genotype. Further studies are required to assess the country-wide distribution of IBDV of different genotypes and the efficacy of the currently available vaccines in protecting chickens against different genotypes of IBDV in Bangladesh.

Reno-pancreas protective effects of Spirulina platensis in alloxan induced diabetic rats.

A large variety of herbal elements are employed in the treatment of diabetes for their better efficacy and safety compare to synthetic drugs. In this experiment Spirulina platensis was used to evaluate the antidiabetic, kidney & pancreas injury protective potential in alloxan induced diabetic rats. Male Long Evans rats having six weeks of age were used for the experiment. Diabetes was induced by intraperitoneal injection of alloxan @ 150 mg/kg and experiment was carried out for a period of six weeks. The study was conducted by dividing the animal into three groups (n=7 rats in each group) indicated as with Group-A (healthy control); Group-B (diabetic control); Group-C (Diabetic rats treated with Spirulina platensis @ 400 mg/kg). Spirulina platensis reduced blood glucose significantly (P<0.01) and improved the body weight losses significantly (P<0.05) compared to diabetic rats after six weeks treatment. The histopathological alteration was observed in the kidney of diabetic rats which was characterized by glomerular hypertrophy, tubular necrosis and interstitial fibrosis. Marked improvements in the histopathological change were noticed in the kidneys of diabetic rats treated with Spirulina platensis. Pancreatic injury was produced by alloxan induction in rats characterized by destruction of the pancreatic ß cells mostly in the central portion of the islets of langerhans and lymphocytic infiltrations, atrophy, and interstitial fibrosis, which were suppressed by Spirulina platensis. In addition, alloxan induced diabetic rats showed increased plasma lipid peroxidase level which was ameliorated by Spirulina platensis treatment. Along with previous report the anticipated results would concluded that Spirulina platensis having antioxidant compounds could protect renal tissues damage, stimulate regeneration and reactivation of pancreatic ß- cells in alloxan induced diabetic rats.

Effect of neem oil biodiesel on the surface and structural integrity of carbon steel alloy: Chromatographic, spectroscopic, and morphological investigations.

This study explores the impacts of neem oil biodiesel (BD), which was produced and characterized using GC-MS, FTIR, and UV-Vis spectroscopic techniques to elucidate pure and corrosion-product neem oil BD at room temperature (25 °C) and different immersion durations of 0, 28, 42, and 56 days. The OM and SEM were also employed to study the surface, structural integrity, and interphase interaction between the BD and the carbon steel (C1020) before and after immersion for different durations. The dominant fatty acid (FA) group in both pure and corrosion-product neem oil BD was C18, with a total composition of 72.3 %, hence determining the nature of the BD interaction with the carbon steel. The study revealed that carbon steel (C1020) was susceptible to attacks by neem oil BD, and the duration of immersion had substantial influence on the surface morphology and structural integrity of the steel. It is therefore anticipated that this study will significantly advance the field of alternative fuel research.

Hybrid multimodule DC-DC converters accelerated by wide bandgap devices for electric vehicle systems.

In response to the growing demand for fast-charging electric vehicles (EVs), this study presents a novel hybrid multimodule DC-DC converter based on the dual-active bridge (DAB) topology. The converter comprises eight modules divided into two groups: four Insulated-Gate Bipolar Transistor (IGBT) modules and four Metal-Semiconductor Field-Effect Transistor (MESFET) modules. The former handles high power with a low switching frequency, while the latter caters to lower power with a high switching frequency. This configuration leverages the strengths of both types of semiconductors, enhancing the converter's power efficiency and density. To investigate the converter's performance, a small-signal model is developed, alongside a control strategy to ensure uniform power sharing among the modules. The model is evaluated through simulation using MATLAB, which confirms the uniformity of the charging current provided to EV batteries. The results show an impressive power efficiency of 99.25% and a power density of 10.99 kW/L, achieved through the utilization of fast-switching MESFETs and the DAB topology. This research suggests that the hybrid multimodule DC-DC converter is a promising solution for fast-charging EVs, providing high efficiency, power density, and switching speed. Future studies could explore the incorporation of advanced wide bandgap devices to handle even larger power fractions.

Production of green hydrogen from sewage sludge / algae in agriculture diesel engine: Performance Evaluation.

Alternative fuel opportunities can satisfy energy security and reduce carbon emissions. In this regard, the hydrogen fuel is derived from the source of environmental pollutants like sewage and algae wastewater through hydrothermal gasification technique using a KOH catalyst with varied gasification process parameters of duration and temperature of 6-30 min and 500-800 °C. The novelty of the work is to identify the optimum gasification process parameter for obtaining the maximum hydrogen yield using a KOH catalyst as an alternative fuel for agricultural engine applications. Influences of gasification processing time and temperature on H2 selectivity, Carbon gasification efficiency (CE), Lower heating value (LHV), Hydrogen yield potential (HYP), and gasification efficiency (GE) were studied. Its results showed that the gasifier operated at 800 °C for 30 min, offering maximum hydrogen yield (26 mol/kg) and gasification efficiency (58 %). The synthesized H2 was an alternative fuel blended with diesel fuel/TiO2 nanoparticles. It was experimentally studied using an internal combustion engine. Influences of H2 on engine performance, like brake-specific fuel consumption, brake thermal efficiency and emission performances, were measured and compared with diesel fuel. The results showed that DH20T has the least (420g/kWh) brake-specific fuel consumption (BSFC) and superior brake thermal efficiency of about 25.2 %. The emission results revealed that the DH20T blend showed the NOX value increased by almost 10.97 % compared to diesel fuel, whereas the CO, UHC, and smoke values reduced by roughly 31.25, 28.34, and 42.35 %. The optimum fuel blend (DH20T) result is recommended for agricultural engine applications.

SCAPS-1D simulated organometallic halide perovskites: A comparison of performance under Sub-Saharan temperature condition.

Photovoltaic technology has been widely recognized as a means to advance green energy solutions in the sub-Saharan region. In the real-time operation of solar modules, temperature plays a crucial role, making it necessary to evaluate the thermal impact on the performance of the solar devices, especially in high-insolation environments. Hence, this paper investigates the effect of operating temperature on the performance of two types of organometallic halide perovskites (OHP) - formamidinium tin iodide (FASnI3) and methylammonium lead iodide (MAPbI3). The solar cells were evaluated under a typical Nigerian climate in two different cities before and after graphene passivation. Using a one-dimensional solar capacitance simulation software (SCAPS-1D) program, the simulation results show that graphene passivation improved the conversion efficiency of the solar cells by 0.51 % (FASnI3 device) and 3.11 % (MAPbI3 device). The presence of graphene played a vital role in resisting charge recombination and metal diffusion, which are responsible for the losses in OHP. Thermal analysis revealed that the MAPbI3 device exhibited an increased fill factor (FF) in the temperature range of 20-64 °C, increasing the power conversion efficiency (PCE). This ensured that the MAPbI3 solar cell performed better in the city and the season with harsher thermal conditions (Kaduna, dry season). Thus, MAPbI3 solar cells can thrive excellently in environments where the operating temperature is below 65 °C. Overall, this study shows that the application of OHP devices in sub-Saharan climatic conditions is empirically possible with the right material modification.

Improvement of mechanical performance on zirconium dioxide nanoparticle synthesized magnesium alloy nano composite.

With excellent mechanical properties and distinct solidification, the AZ31B series magnesium alloy has great potential for targeting engineering applications and synthesized via die casting process found a drawback on oxidation results porosity and reduced mechanical properties. Here, the magnesium alloy AZ31B series nanocomposite was synthesized with varied weight percentages of zirconium dioxide nanoparticles through a liquid metallurgy route with an applied stir speed of 200 rpm under an argon nature. With the help of a scanning electron microscope, the distribution of particles in the composite surface was found to be homogenous and void-free surface, which output results in less percentage of porosity (<1 %), and the composite contained 6 wt% ZrO2 offers superior yield strength (212 ± 3 MPa), tensile strength (278 ± 2 MPa), and impact strength of 16.4 ± 0.4 J/mm2. In addition, 8 wt% ZrO2 blended composite showed the maximum microhardness value (78.3 ± 1 HV). The best-enhanced result of NC3 (AZ31B/6 wt% ZrO2) is suggested for lightweight to high-strength structural applications.

Tuning the optoelectronic properties of acridine-triphenylamine (ACR-TPA) based novel hole transporting material for high efficiency perovskite and organic solar cell.

In this research, five distinct small donor molecules (designated as ACR-TPA-X1, ACR-TPA-X2, ACR-TPA-X3, ACR-TPA-X4, ACR-TPA-X5) are constructed by replacing the methoxy groups on both sides of the model molecule (ACR-TPA-R) with thiophene bridged acceptor moieties. We have used the B3LYP/6-31G (d,p) model for our computational studies. Our model molecule's morphological alteration has resulted in a lowered Eg of 1.77-2.51 eV as compared to model (ACR-TPA-R=3.84 eV). ACR-TPA-X2 investigated the λmax at 776 nm. ACR-TPA-X4 was found to be most miscible with dichloromethane (DCM). The greatest VOC(1.21 eV) was observed in ACR-TPA-X1. Among all of the variants, ACR-TPA-X1 had the highest PCE (23.42%). It was found that ACR-TPA-X4 had the highest electron mobility (0.00370 eV) and ACR-TPA-X5 had the highest hole mobility (0.00324 eV) of all the materials examined. The findings prove the worth of the methods used, paving the way for the development of effective small donors for OSCs and HTMs for PSCs.

Methoxy triphenylamine hexaazatrinaphthylene based small molecules as donor material for photovoltaic applications.

Organic solar cells (OSCs) are capturing huge interest because of their numerous benefits, which include transparency, flexibility, and solution processability. In current project, five new donor molecules (J1-J5) were designed by employing the strategy of end capped alteration of the acceptor moieties on the two sides of the reference molecule. The Methoxy Triphenylamine hexaazatrinaphthylene (MeO-TPA-HATNA) have been used as a reference molecule in this study. DFT and TD-DFT methods employing B3LYP/6-31G (d, p) functional has been applied to perform different analysis. Geometrical, and opto-electronic features of all tailored chromophores were investigated, and comparison was made with the reference J. Among all tailored molecules, J5 shows highest λmax (862 nm) with the least band gap of 1.28 eV. TDM and DOS analysis revealed the high rate of charge transfer. Further, reorganization energy calculations are also executed to examine the charge transfer features of the designed molecules. The results shows that J5 among all these molecules has the highest rate of charge carrier (electron and hole) mobility with least RE values and this molecule can be used as a promising donor material for OSCs with remarkable charge transferring properties. Furthermore, the designed materials showed a suitable HOMO along with higher LUMO energy levels with respect to PC61BM molecule and coupling the PC61BM acceptor with investigated donor molecules gives highly increased Voc (0.66-0.76 V) than reference molecule (0.49 V) and also the power conversion efficiency (PCE) is elevated to 15.09%. The outcomes of current theoretical research have demonstrated that the end capped alteration of different acceptor groups is an excellent strategy to get OSCs with desirable photovoltaic performance. As, all the newly created molecules (J1-J5) have exhibited outstanding electronic and optical properties therefore, these can be expectedly prove excellent material for creating high efficiency future organic photovoltaic devices.

Experimental Pathogenicity of H9N2 Avian Influenza Viruses Harboring a Tri-Basic Hemagglutinin Cleavage Site in Sonali and Broiler Chickens.

Low-pathogenic avian influenza (LPAI) H9N2 virus is endemic in Bangladesh, causing huge economic losses in the poultry industry. Although a considerable number of Bangladeshi LPAI H9N2 viruses have been molecularly characterized, there is inadequate information on the pathogenicity of H9N2 viruses in commercial poultry. In this study, circulating LPAI H9N2 viruses from recent field outbreaks were characterized, and their pathogenicity in commercial Sonali (crossbred) and broiler chickens was assessed. Phylogenetic analysis of currently circulating field viruses based on the hemagglutinin (HA) and neuraminidase (NA) gene sequences revealed continuous circulation of G1 lineages containing the tri-basic hemagglutinin cleavage site (HACS) motif (PAKSKR*GLF) at the HA protein. Both the LPAI susceptible Sonali and broiler chickens were infected with selected H9N2 isolates A/chicken/Bangladesh/2458-LT2/2020 or A/chicken/Bangladesh/2465-LT56/2021 using intranasal (100 µL) and intraocular (100 µL) routes with a dose of 106 EID50/mL. Infected groups (LT_2-So1 and LT_56-So2; LT_2-Br1 and LT_56-Br2) revealed no mortality or clinical signs. However, at gross and histopathological investigation, the trachea, lungs, and intestine of the LT_2-So1 and LT_56-So2 groups displayed mild to moderate hemorrhages, congestion, and inflammation at different dpi. The LT 2-Br1 and LT 56-Br2 broiler groups showed nearly identical changes in the trachea, lungs, and intestine at various dpi, indicating no influence on pathogenicity in the two commercial bird species under study. Overall, the prominent lesions were observed up to 7 dpi and started to disappear at 10 dpi. The H9N2 viruses predominantly replicated in the respiratory tract, and higher titers of virus were shed through the oropharyngeal route than the cloacal route. Finally, this study demonstrated the continuous evolution of tri-basic HACS containing H9N2 viruses in Bangladesh with a low-pathogenic phenotype causing mild to moderate tracheitis, pneumonia, and enteritis in Sonali and commercial broiler chickens.

Electrospun cellulose acetate/activated carbon composite modified by EDTA (rC/AC-EDTA) for efficient methylene blue dye removal.

The present study fabricated regenerated cellulose nanofiber incorporated with activated carbon and functionalized rC/AC3.7 with EDTA reagent for methylene blue (MB) dye removal. The rC/AC3.7 was fabricated by electrospinning cellulose acetate (CA) with activated carbon (AC) solution followed by deacetylation. FT-IR spectroscopy was applied to prove the chemical structures. In contrast, BET, SEM, TGA and DSC analyses were applied to study the fiber diameter and structure morphology, the thermal properties and the surface properties of rC/AC3.7-EDTA. The CA was successfully deacetylated to give regenerated cellulose nanofiber/activated carbon, and then ethylenediaminetetraacetic acid dianhydride was used to functionalize the fabricated nanofiber composite. The rC/AC3.7-EDTA, rC/AC5.5-EDTA and rC/AC6.7-EDTA were tested for adsorption of MB dye with maximum removal percentages reaching 97.48, 90.44 and 94.17%, respectively. The best circumstances for batch absorption experiments of MB dye on rC/AC3.7-EDTA were pH 7, an adsorbent dose of 2 g/L, and a starting MB dye concentration of 20 mg/L for 180 min of contact time, with a maximum removal percentage of 99.14%. The best-fit isotherm models are Temkin and Hasely. The outcome of isotherm models illustrates the applicability of the Langmuir isotherm model (LIM). The maximal monolayer capacity Qm determined from the linear LIM is 60.61 for 0.5 g/L of rC/AC3.7-EDTA. However, based on the results from error function studies, the generalized isotherm model has the lowest accuracy. The data obtained by the kinetic models' studies exposed that the absorption system follows the pseudo-second-order kinetic model (PSOM) throughout the absorption period.

Poultry waste management practices in Bangladesh: Farmer's perceptions, and food and environmental hazards.

Objective: The poultry industry plays a key role in developing socio-economic and health sectors in Bangladesh. Poultry waste is a potential environmental threat as untreated poultry waste is used in vegetable gardens. The study aimed to investigate the current situation of small-scale poultry farms and their waste management practices in selected areas of Bangladesh and detect Escherichia coli and Salmonella in vegetables from farms using untreated poultry waste as fertilizer. Materials and Methods: A structured questionnaire-based survey was conducted in 86 small-scale poultry farms from different upazilas of Mymensingh and Khulna districts. 104 samples, including vegetables, poultry litter, water, and soil, were collected from vegetable gardens, ponds, fields, and wet markets in Mymensingh district to detect microbial contamination. Bacteria were identified based on their growth and colony morphology on selective media and motility tests. The presence of E. coli and Salmonella was confirmed by polymerase chain reaction (PCR) using a commercial PCR kit. Results: The survey revealed that mostly middle-aged males were involved in poultry farming. Most of the farmers had primary education and engaged in farming for about 5 years without training. In the study area, 37% of farmers collected droppings daily in the morning and used them as organic fertilizer. About 58% of farmers did not know the hygienic handlings of droppings and faced health problems. In PCR, either E. coli or Salmonella or both were confirmed in vegetables, litter, soil, and pond water. Conclusion: Appropriate poultry waste management practices can reduce the possible contamination of microbial agents in the human food chain.

Designing of phenothiazine-based hole-transport materials with excellent photovoltaic properties for high-efficiency perovskite solar cells (PSCs).

In this study, a series of highly efficient organic hole-transporting materials (HTMs) were designed using Schiff base chemistry by modifying a phenothiazine-based core with triphenylamine through end-capped acceptor engineering via thiophene linkers. The designed HTMs (AZO1-AZO5) exhibited superior planarity and greater attractive forces, making them ideal for accelerated hole mobility. They also showed deeper HOMO energy levels (-5.41 eV to -5.28 eV) and smaller energy band gaps (2.22 eV to 2.72 eV), which improved charge transport behavior, open-circuit current, fill factor, and power conversion efficiency of perovskite solar cells (PSCs). The dipole moments and solvation energies of the HTMs revealed their high solubility, making them suitable for the fabrication of multilayered films. The designed HTMs showed tremendous enhancements in power conversion efficiency (26.19 % to 28.76 %) and open-circuit voltage (1.43 V to 1.56 V), with higher absorption wavelength than the reference molecule (14.43 %). Overall, the Schiff base chemistry-driven design of thiophene-bridged end-capped acceptor HTMs is highly effective in enhancing the optical and electronic properties of perovskite solar cells.

Impact of hole transport material on perovskite solar cells with different metal electrode: A SCAPS-1D simulation insight.

The high efficiency and low cost of production of perovskite solar cells (PSCs) based on organic-inorganic halides have attracted the attention of researchers. However, due to the intricacy in the synthesis of Spiro-OMeTAD and the high cost of gold (Au) utilized as the back contact (BC), have affected its viability for commercialization. In this present study, a simulation was performed with and without HTM utilizing different metal contacts (Ag, Cr, Cu, Au, Ni and Pt). SCAPS-1D, a software program in one dimension, was used to conduct the simulation. A systematic analysis was done to determine how the metal back contact's work functions affected the PSC both with and without HTM. The outcomes demonstrate that the PSCs' photovoltaic performance is significantly influenced by the metal contact's work function (WF). The best metal contact for HTM and HTM-free devices was Pt, with a metal work function of 5.65 eV. The initial power conversion efficiencies (PCEs) for the two configurations were 26.229% for HTM-free and 25.608% for HTM-based device. A number of parameters, including absorber thickness, interface defect density, and electron transport material (ETM) thickness, were varied to obtain optimal values of 0.8 µm for both HTM and HTM-free PSCs, 1005 cm-2 for both HTM and HTM-free PSCs, and 0.01 µm for both HTM and HTM-free PSCs. These values were then used to simulate the final HTM and HTM-free devices with a PCE of 27.423%, current density (Jsc) of 27.546 mA/cm2, open circuit voltage (Voc) of 1.239 V, and fill factor (FF) of 80.347% for HTM-free whereas PCE of 26.767% with Jsc of 27.545 mA/cm2, Voc of 1.250 V, and FF of 77.733% for HTM based. These outcomes reflect outstanding enhancement of ∼1.05 and ∼1.07 times in PCE and Jsc over unoptimized cells with and without HTM.

Designing an efficient lead-free perovskite solar cell with green-synthesized CuCrO2 and CeO2 as carrier transport materials.

With increased efficiency, simplicity in manufacturing, adaptability, and flexibility, solar cells constructed from organic metal halide perovskite (PVK) have recently attained great eminence. Lead, a poisonous substance, present in a conventional PVK impacts the environment and prevents commercialization. To deal with this issue, a number of toxicity-free PVK-constructed solar cells have been suggested. Nevertheless, inherent losses mean the efficiency conversion accomplished from these devices is inadequate. Therefore, a thorough theoretical investigation is indispensable for comprehending the losses to improve efficiency. The findings of a unique modelling method for organic lead-free solar cells, namely methylammonium tin iodide (MASnI3), are investigated to reach the maximum practical efficiencies. The layer pertinent to MASnI3 was constructed as a sandwich between a bio-synthesized electron transport layer (ETL) of CeO2 and a hole transport layer (HTL) of CuCrO2 in the designed perovskite solar cells (PSCs). In this study, the use of algae-synthesized Au in the back contacts has been proposed. To obtain the maximum performance, the devices are further analyzed and optimized for active layer thickness, working temperature, total and interface defect density analysis, impedance analysis (Z'-Z), and capacitance-voltage (C-V), respectively. An optimal conversion efficiency of 26.60% has been attained for an MASnI3-constructed PSC. The study findings may open the door to a lead-free PSC through improved conversion efficiencies.

A Booster with a Genotype-Matched Inactivated Newcastle Disease Virus (NDV) Vaccine Candidate Provides Better Protection against a Virulent Genotype XIII.2 Virus.

Newcastle disease (ND) is endemic in Bangladesh. Locally produced or imported live Newcastle disease virus (NDV) vaccines based on lentogenic virus strains, locally produced live vaccines of the mesogenic Mukteswar strain, as well as imported inactivated vaccines of lentogenic strains, are being used in Bangladesh under different vaccination regimens. Despite these vaccinations, frequent outbreaks of ND are being reported in Bangladesh. Here we compared the efficacy of booster immunization with three different vaccines in chickens that had been primed with two doses of live LaSota vaccine. A total of 30 birds (Group A) were primed with two doses of live LaSota virus (genotype II) vaccine at days 7 and 28, while 20 birds (Group B) remained unvaccinated. At day 60, birds of Group A were divided into three sub-groups, which received booster immunizations with three different vaccines; A1: live LaSota vaccine, A2: inactivated LaSota vaccine, and A3: inactivated genotype XIII.2 vaccine (BD-C161/2010 strain from Bangladesh). Two weeks after booster vaccination (at day 74), all vaccinated birds (A1-A3) and half of the unvaccinated birds (B1) were challenged with a genotype XIII.2 virulent NDV (BD-C161/2010). A moderate antibody response was observed after the primary vaccination, which substantially increased after the booster vaccination in all groups. The mean HI titers induced by the inactivated LaSota vaccine (8.0 log2/5.0 log2 with LaSota/BD-C161/2010 HI antigen) and the inactivated BD-C161/2010 vaccine (6.7 log2/6.2 log2 with LaSota/BD-C161/2010 HI antigen) were significantly higher than those induced by the LaSota live booster vaccine (3.6 log2/2.6 log2 with LaSota/BD-C161/2010 HI antigen). Despite the differences in the antibody titers, all chickens (A1-A3) survived the virulent NDV challenge, while all the unvaccinated challenged birds died. Among the vaccinated groups, however, 50% of the chickens in Group A1 (live LaSota booster immunization) shed virus at 5- and 7-days post challenge (dpc), while 20% and 10% of the chickens in Group A2 (inactivated LaSota booster immunization) shed virus at 3 and 5 dpc, respectively, and only one chicken (10%) in Group A3 shed virus at 5 dpc. In conclusion, the genotype-matched inactivated NDV booster vaccine offers complete clinical protection and a significant reduction in virus shedding.

Current state of poultry waste management practices in Bangladesh, environmental concerns, and future recommendations.

This review paper focuses on the current state of poultry waste generation, composition, and management techniques in commercial poultry farms and trading in Bangladesh, to reduce pollution and generate economic benefits from poultry waste. It also underlines the negative impact of poultry waste disposal on the environment. In Bangladesh, collection of poultry waste into bags and, subsequently, direct use as fertilizer in agricultural fields and aquaculture is common, while alternative disposal methods such as composting and biogas generation are now attracting commercial poultry producers. Direct use of poultry manure results in poor air and soil quality, environmental deterioration, detrimental effects on global health, climate change due to high levels of atmospheric ammonia, and the creation of significant amounts of greenhouse gases. Lack of knowledge and investment, as well as high demand for free land for composting, are important obstacles. Future research on precise waste characterization, improved understanding of poultry waste management, and increased efforts on developed waste disposal for a safe environment are therefore recommended. So, poultry waste, which is currently a burden for the environment, could be turned into a useful agricultural resource, which would be useful for the poultry industry.

Manufacturing and compatibilization of binary blends of superheated steam treated jute and poly (lactic acid) biocomposites by melt-blending technique.

This work investigated the effect of superheated steam (SHS) jute fiber and poly (lactic acid) (PLA) having a weight proportion of 30:70 which were synthesized using the melt blending method. The goal of this treatment was to boost up the fiber-polymer interfacial linkage. The action was conducted in a superheated steam oven at various times (30-120 min) and temperatures (170-220 °C). The biocomposites were assessed in terms of mechanical characteristics, dimensional stability and morphological properties. Compared to different treatment temperatures, the results showed that treatment at 210 °C for 60 min offered the best tensile characteristics. Because of the presence of SHS-Jute, the tensile, impact, bending and dimensional stability of the bio-composites have been improved. The FTIR and SEM study revealed progress in the interfacial linkage between SHS-Jute and PLA. This interfacial link improves the bending strength of SHS-Jute-PLA biocomposites by about 15.64%. X-ray diffraction (XRD) investigation also showed an elevation in the crystalline structure with the incorporation of SHS-Jute. The degradation tests of the biocomposite were carried out in deionized water. SHS treatment reduces hemicellulose contents in jute fiber which causes water uptake% reduction is 54% in SHS-Jute-PLA. The SHS-Jute-PLA biocomposite appeared with promising characteristics for utilization as a green and ecological substitute particle board material.

Design and Parametric Analysis of a Wide-Angle and Polarization Insensitive Ultra-Broadband Metamaterial Absorber for Visible Optical Wavelength Applications.

Researchers are trying to work out how to make a broadband response metamaterial absorber (MMA). Electromagnetic (EM) waves that can pass through the atmosphere and reach the ground are most commonly used in the visible frequency range. In addition, they are used to detect faults, inspect tapped live-powered components, electrical failures, and thermal leaking hot spots. This research provides a numerical analysis of a compact split ring resonator (SRR) and circular ring resonator (CRR) based metamaterial absorber (MMA) using a three-layer substrate material configuration for wideband visible optical wavelength applications. The proposed metamaterial absorber has an overall unit cell size of 800 nm × 800 nm × 175 nm in both TE and TM mode simulations and it achieved above 80% absorbance in the visible spectrums from 450 nm to 650 nm wavelength. The proposed MA performed a maximum absorptivity of 99.99% at 557 nm. In addition, the steady absorption property has a broad range of oblique incidence angle stability. The polarization conversion ratio (PCR) is evaluated to ensure that the MMA is perfect. Both TM and TE modes can observe polarization insensitivity and wide-angle incidence angle stability with 18° bending effects. Moreover, a structural study using electric and magnetic fields was carried out to better understand the MMA's absorption properties. The observable novelty of the proposed metamaterial is compact in size compared with reference paper, and it achieves an average absorbance of 91.82% for visible optical wavelength. The proposed MMA also has bendable properties. The proposed MMA validation has been done by two numerical simulation software. The MMA has diverse applications, such as color image, wide-angle stability, substantial absorption, absolute invisible layers, thermal imaging, and magnetic resonance imaging (MRI) applications.