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The emergence of Salmonella enterica serovars that produce extended-spectrum beta-lactamase and exhibit multi-drug resistance (MDR) poses a substantial global threat, contributing to widespread foodborne illnesses and presenting an alarming issue for public health. This study specifically concentrated on the isolation and identification of ESBL-resistant genes (blaTEM, blaSHV, blaCTX-M1, blaCTX-M2, blaCTX-M9, MultiCaseACC, MultiCaseMOX, MultiCaseDHA, blaOXA) and the antibiogram profiling of Salmonella enterica serovars found in goat meat samples procured from retail outlets in Bangladesh. During the research in the Sylhet district of Bangladesh, researchers gathered a total of 210 samples of goat meat from 13 different Upazilas. Primarily, cultural and biochemical methods were used for isolation of bacteria from the selected samples. Salmonella enterica serovars Typhimurium and Enteritidis, along with three ESBL-resistant genes, were identified through polymerase chain reactions (PCRs). The disk diffusion test was used to determine antimicrobial susceptibilities. Out of 210 samples analysed, Salmonella spp. was detected in 18.10 % (38 out of 210), with S. Enteritidis and S. Typhimurium found in 9.05 % (19 out of 210) and 5.24 % (11 out of 210) of the samples, respectively. A total of 72.73 % (8/11) of S. Enteritidis and 100 % (19/19) of S. Typhimurium isolates were positive by Multidrug-resistant patterns. The positive outcomes were found of S. Typhimurium tested 63.16 % (12 out of 19) for the blaTEM gene and 21.05 % (4/19) for the blaSHV, gene. The study proposes that the retail goat meat market channel could be a prominent transmission way of ESBL-producing MDR Salmonella enterica serovars, representing a significant public health hazard.

Different physical properties of ternary intermetallic La-based superconducting materials LaM2Si2 (M = Co, Cu, Rh, Pd, Ag, Ir, Pt, Au) are examined through the self consistent ab-initio scheme depending on the DFT replication. The main purpose of this study is to comprehend several different crucial characteristics of these compounds, including their crystal phase, stability manner, bulk features, band configuration, dielectric, conductivity as well as thermal features. Good accordance in the structural analysis of superconducting materials LaM2Si2 (M = Co, Cu, Rh, Pd, Ag, Ir, Pt, Au) has been observed between the optimized and synthesized lattice parameters. The phonon dispersion curve indicates that the compounds LaCo2Si2, LaCu2Si2, LaRh2Si2, LaPd2Si2, and LaIr2Si2 are dynamically stable, but LaAg2Si2, LaPt2Si2, and LaAu2Si2 are dynamically unstable in nature. Mechanical crystal constancy of the selected materials is verified from the investigated elastic constants. Ductility behaviors of these compounds are ensured by the values of Pugh's and Poisson's ratios. High Young's modulus of LaIr2Si2 ensured its elevated hardness along with huge melting temperature compared than other phases. Anisotropic character of these materials can be ensured through the calculations of elastic anisotropy. The electrical properties of the superconducting LaM2Si2 (M = Co, Cu, Rh, Pd, Ag, Ir, Pt, Au) compounds were also studied in details. Metallic character of the selected solids is observed through the investigation of DOS and band structure calculations. The investigated dielectric function, conductivity, and absorption also reflect the conductive behavior of superconducting LaM2Si2 (M = Co, Cu, Rh, Pd, Ag, Ir, Pt, Au) materials. The optical phenomena ensured their huge absorption as well as optical conductive nature at the site of ultraviolet energy region. Moreover, high reflectivity in the UV region makes these superconductors good solar reflectors for this energy site. Very low minimum thermal conductivity of these compounds especially of LaPt2Si2 and LaAu2Si2 makes them useful and fascinating for thermal barrier coating (TBC) materials.

Density functional theory (DFT) based first-principles calculations using GGA+U method have been performed for the first time to investigate elastic, electronic, optical, thermodynamic properties including charge density, Fermi surface, Mulliken population analysis, and theoretical Vickers hardness of the newly synthesized LiCuBiO4 (LCBO) compound. The calculated structural parameters are in good agreement with available experimental results, which assessed the reliability of our calculations. The analysis of elastic constants indicates mechanical stability of the LCBO. The values of Poisson's and Pugh's ratios confirm the ductile nature of the LCBO. The mechanically anisotropy is found by the different anisotropy factors. The overlapping of valence and conduction bands near the Fermi level (EF) and the several bands crossing the EF reveal the metallic behaviour of the LCBO. The electronic charge density mapping and Mulliken population analysis exhibits a combination of covalent, ionic, and metallic bonding of the LCBO. The calculated Fermi surface comprised of two-dimensional topology due to the low-dispersion of O-2p and Cu-3d states, which implies the possible multi-band nature of LCBO. The analysis of thermodynamic and various optical properties suggest that LCBO can be a potential candidate for optoelectronic devices in the visible and ultraviolet energy regions and as a thermal barrier coating (TBC) material. Keywords: DFT calculations, Mechanical properties, Electronic properties, Optical properties, Thermodynamic properties

Subclinical mastitis (SCM), a silent threat in the dairy sector of Bangladesh poses a significant economic impact and serves as a potential source of infection for healthy cows, hindering efforts to achieve milk self-sufficiency. Despite the importance of this issue, limited research has been conducted on mastitis in Sylhet region of Bangladesh. This study aimed to investigate the molecular prevalence, antimicrobial susceptibility profile and resistant genes detection on pathogens (Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae) causing SCM. In a cross-sectional study utilizing convenience sampling, 325 milk samples were collected from apparently healthy dairy cows. Initially, SCM was detected using the modified Whiteside test (MWST) method. Suspected positive samples were then subjected to bacteriological culture and standard biochemical assays, followed by molecular identification through polymerase chain reaction (PCR). Finally, antimicrobial susceptibility testing was conducted on all PCR-positive samples using the Kirby-Bauer disk diffusion method on Mueller-Hinton agar. In the Sylhet district, the prevalence of SCM was 64.92 % (211 out of 325) at the individual animal level and 82.69 % (43 out of 52) at the herd level. Among the SCM-positive animals, S. aureus was found in 31.75 % (67 out of 211) of cases, E. coli in 81.99 % (173 out of 211), and K. pneumoniae in 66.82 % (141 out of 211). K. pneumoniae had the highest prevalence at 60 % in Zakiganj, S. aureus at 45 % in Zakiganj, and E. coli at 72 % in Bishwanath Upazila. Extended spectrum beta lactamase (ESBL) genes blaTEM, blaOXA, blaCTX-M1, blaCTX-M2, MultiCaseDHA were identified. Additionally, antibiotic resistance genes tet(A), AAC(3)-iv, and Sul1 were also detected. The pathogens exhibited resistance to Penicillins (ampicillin, amoxicillin), Cephems (cefuroxime, ceftazidime), and Tetracyclines (tetracycline). However, all three bacteria were highly sensitive to meropenem, amikacin, gentamicin, ciprofloxacin, and sulfamethoxazole-trimethoprim. These findings highlight the critical need for targeted antimicrobial stewardship and effective control measures to mitigate the impact of SCM on dairy production and animal health in the Sylhet region of Bangladesh.

Alloys of the Fe–Cr–C–B–Ti alloy system are characterized by brittleness, which can be eliminated by the copper alloy, while corrosion resistance and abrasive wear resistance are significantly reduced. In this article, comprehensive investigations are carried out on the microstructure and mechanical properties of the proposed high-copper boron-containing alloy 110Cr4Cu7Ti1VB. Systematic theoretical and experimental studies encompassed thermodynamic calculations in ThermoCALC, production of flux-cored wires for hardfacing and welding, receipt of SEM images, acquisition of load and unload diagrams (discharge) via instrumental indentation on various phases of the deposited metal, and determination of chemical composition at indentation points through local chemical analysis. Mechanical properties of some phases such as γ–Fe phase (austenite), hemioboride Fe2(В,С) and boron cementite Fe3(В,С) and titanium carbide TiC in Fe–Cr–C–B–Ti–Сг alloy were determined by using density functional theory (DFT) implemented in the CASTEP code. We also compared these compounds; properties with other available commercial compounds, where available. With the knowledge of calculated elastic constants, the moduli, the Pugh's modulus ratio G/B, the Poisson's ratio v and the hardness of the title phases, 110Cr4Cu7Ti1VB were further predicted and discussed.