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311.
Saeed A. Khan Kidon Sung Mohamed S. Nawaz Carl E. Cerniglia Mark L. Tamplin Robert W. Phillips Lynda Collins Kelley 《Food microbiology》2009
In this study, we investigated the survival and inactivation kinetics of a surrogate strain of Bacillus anthracis (Sterne strain) in whole egg (WE), egg white (EW), sugared egg yolk (YSU), and salted egg yolk (YSA) at low (−20, 0, and 5 °C), moderate (15, 20, 25, 30, 35, and 40 °C), and high storage temperatures (45, 50, 55, and 60 °C). Outgrowth of the spores was measured as lag phase duration (LPD). Replication of vegetative cells was measured in terms of growth rate (GR) and maximum population density (MPD). Spore inactivation was recorded as inactivation rate and percent reduction in viable count. In general, spore viability decreased at low and high temperatures and increased at moderate temperatures. At 0 and 5 °C, a 60–100% reduction in spore viability was seen within 2–3 weeks in WE and YSU, 0–30% in YSA, and 50–100% in EW. At −20 °C, however, no drop in spore titer was observed in YSU and EW but a 20% drop in titer was seen in YSA and 50% in WE within 2–3 weeks. At high temperatures, WE, EW, and YSA produced a 20–50% drop in the spore titer within 1–4 h whereas YSU showed 100% inactivation within 0.75 h. At moderate storage temperatures, as the temperature increased from 15 to 40 °C, LPD decreased from 13.5 to 0.75 h and MPD reached 0.27–2.2 × 109 CFU/ml in YSU and WE, respectively. Markedly lower growth was observed in YSA (LPD = 24–270 h, MPD = 9 × 105 CFU/ml) and spores were inactivated completely within 1–6 h in EW. The survivability and inactivation data of B. anthracis in liquid egg products reported in this investigation will be helpful in developing risk assessment models on food biosecurity. 相似文献
312.
M.Y. Nawaz F. Jimenez-Krassel J.P. Steibel Y. Lu A. Baktula N. Vukasinovic L. Neuder J.L.H. Ireland J.J. Ireland R.J. Tempelman 《Journal of dairy science》2018,101(9):8063-8075
Anti-Müllerian hormone (AMH) is an ovarian growth factor that plays an important role in regulation of ovarian follicle growth. The objectives of this study were to estimate the genomic heritability of AMH and identify genomic regions associated with AMH production in a genome-wide association (GWA) analysis. Concentrations of AMH were determined in 2,905 dairy Holstein heifers genotyped using the Zoetis medium density panel (Zoetis Inclusions, Kalamazoo, MI) with 54,519 single nucleotide polymorphism (SNP) markers remaining after standard genotype quality control edits. A linear mixed model was used to model the random effects of sampling day and genomics on the logarithm of AMH. The genomic heritability (± standard error of the mean) of AMH was estimated to be 0.36 ± 0.03. Our GWA analysis inferred significant associations between AMH and 11 SNP markers on chromosome 11 and 1 SNP marker on chromosome 20. Annotated genes with significant associations were identified using the Ensembl genome database (version 88) of the cow genome (version UMD 3.1; https://www.ensembl.org/biomart). Gene set enrichment analysis revealed that 2 gene ontology (GO) terms were significantly enriched in the list of candidate genes: G-protein coupled receptor signaling pathway (GO:0007186) and the detection of chemical stimulus involved in sensory perception (GO:0050907). The estimated high heritability and previously established associations between AMH and ovarian follicular reserve, fertility, longevity, and superovulatory response in cattle implies that AMH could be used as a biomarker for genetic improvement of reproductive potential. 相似文献
313.
The effect of different rehydration temperatures (30, 40, and 50°C) and cooking times (2.7, 4.7, 6.7, 8.7, and 10.7 min) at 95°C on the pasting properties of three glutinous varieties (Thadokkham-11, Thadokkham-8, and Hom Mali Niaw) from Lao People’s Democratic Republic was investigated using rapid visco analyzer. Non-glutinous varieties (IR64 and Doongara) were also analyzed to compare glutinous (amylose <4.5%) and non-glutinous (amylose >15%) varieties. All rice flours took up water at significantly (p < 0.05) higher rates in the case of increased temperature and soaking time, resulting in a decrease in the onset temperature for pasting. Among the glutinous rices, Thadokkham-8 showed a significant (p < 0.05) decrease in peak viscosity in response to increased rehydration time and temperature. For this variety maximum viscosity (2403.3 mPas) was observed at 1 min of rehydration at 30°C and minimum viscosity (1852.0 mPas) at 15 min of rehydration at 50°C. The viscosity values of Thadokkham-11 and Hom Mali Niaw varieties increased to their highest values (1608.7 and 1477.7 mPa.s, respectively) with an increase in temperature to 40°C for 1 min. In general, the glutinous rices produced weaker gel than non-glutinous rices. Extended holding at cooking temperature (95°C) had a more significant (p < 0.05) effect on the glutinous varieties Thadokkham-8 and Thadokkham-11 than on the non-glutinous varieties (IR64 and Doongara) used in this study. 相似文献
314.
315.
Oleg Rybin Muhammad Raza Tahira Nawaz Tahir Abbas 《AEUE-International Journal of Electronics and Communications》2009,63(8):648-652
In this paper, analytical modeling and numerical simulation of the complex effective dielectric, magnetic constants and refractive index of a metallic rod metamaterial in microwave frequency range are presented. Analytical modeling has been done using modified mathematical models of the complex dielectric and magnetic constants obtained for rod metamaterial structure. Numerical simulation of the above-mentioned parameters has been made using S-parameters obtained with the help of finite-difference time-domain (FDTD) calculations. The numerical simulation has been carried out for different thickness of rods. Remarkable coincidence between analytical and numerical results was found. The effective dielectric constant enhancement of the considered composite has been obtained. Recommendations for the practical application of considered metamaterial structure for designing patch antennas have been discussed. 相似文献
316.
Catalysis Letters - Lipase-mediated polymer degradation is a robust alternative approach to conventional methods due to biocompatibility and mild conditions. In the present study, response surface... 相似文献
317.
Silicon - The work is aimed at characterizing the properties of slag obtained from CaO-CaF2- TiO2-SiO2 based coatings developed for welding the offshore structures. Extreme vertices methodology was... 相似文献
318.
319.
320.
Tooba Sahar;Rahma Tamime;Muhammad Usman;Hamad AlMohamadi;R. Nawaz;Tanzila Anjum;Asim Laeeq Khan; 《应用聚合物科学杂志》2024,141(48):e56295
In response to the pressing need for effective removal of heavy metals from water sources, this study focuses on the optimization of Thin Film Composite nanofiltration membranes, known for their porous polymer support and selective ultrathin layers. The objective was to enhance the rejection of heavy metal ions, a critical issue in water treatment. The parameters of the interfacial polymerization (IP) process, including monomer concentration, reaction time, curing temperature, and curing duration, were tailored to determine the most effective membrane configuration. Polyimide (P84) was employed as the support material, with the IP involving trimesoyl chloride (TMC) and piperazine (PIP). Comprehensive characterization through Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and water contact angle measurements provided information on the functional groups, surface and cross-sectional morphologies, and hydrophilic properties of the membranes. The optimized fabrication conditions, involving 0.2 w/v% TMC and 2.0 w/v% PIP monomer concentrations, a 2-minute IP reaction time, and a 40°C curing temperature for 10 minutes, led to the membranes achieving arsenic and chromium rejections of 89.7% and 99%, respectively. This was accomplished while maintaining a high pure water permeability of approximately 16.9 Lm−2h−1bar−1. These promising results highlight the potential of these optimized nanofiltration membranes for industrial applications, addressing a critical environmental challenge. 相似文献