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901.
An evaluation of selected methods for the decontamination of cattle hides prior to skinning 总被引:1,自引:0,他引:1
The effectiveness of different decontamination treatments in reducing microbial loads on cattle hides was assessed. The 10-s hide treatments were conducted using a wet-and-dry vacuum cleaner filled with one of the liquids (heated to 50 °C) indicated below, followed or not by 10-min drying in the air. Also, the hide was clipped, followed or not by 10-s singeing using a hand-held blowtorch. Before and after each decontamination treatment, the hide was sampled (100 cm(2) areas) by a sponge-swabbing method to compare the total viable counts of bacteria (TVC). The largest bacterial reduction (P<0.001; 2.31log(10) cfu/cm(2)) was achieved by singeing of previously clipped hide. Treatment of hide with a food industry sanitizer solution (10% Betane Plus) resulted in significant reductions of 1.80 (P<0.001) and 1.98log(10) cfu/cm(2) (P<0.001) without and with subsequent drying, respectively. Treatment of hide with a food industry disinfectant (P3-Topactive DES) significantly reduced TVC by 0.97 (P<0.001) and 1.18log(10) cfu/cm(2) (P<0.001) without and with subsequent drying, respectively. Treatments of hide with water alone or with a food-safe detergent solution (Formula 963B), or hide clipping alone, did not produce significant decontamination effects. Since hide contamination is associated with microbial contamination of the carcasses, the results indicate that post-killing/pre-skinning hide decontamination (used alone, or in combination with carcass decontamination) has a potential to improve microbial meat safety. Nevertheless, further research is required to optimise the efficacy of these treatments in the reduction of specific pathogens under commercial conditions. 相似文献
902.
中国建筑设计院小城填发展研究中心 《小城镇建设》2006,(9):18-19
自2003年建设部、国家文物局开展历史文化名镇(村)评选工作以来,各地有关部门对历史文化镇(村)的认识进一步提高,保护工作也取得了实质性进展。随着评选工作的深入开展,各地参加评选工作的积极性增强,参评单位与日俱增。为全面反映评选工作的开展情况,促进保护工作的广泛开展,本刊推出特别策划——历史文化名镇(村)点评暨风貌展示,向读者介绍评选过程,并给各地申报工作提供了全面参考。在获得“中国历史文化名镇(村)”称号的名镇名村中,她们的特色各有千秋,或历史悠久、或人才辈出、或保留了建筑遗存等等,能深入了解其蕴藏的历史文化内涵,将使我们对名镇(村)的理解更为全面、透彻。为此,本刊特约相关专家对一些镇、村做出点评,沿着专家的评析脉络以及历史文化名镇(村)的风貌展示,希望给予读者更为直观、生动的感受,历史文化名镇(村)能为更多的国人所了解。让保护与传承历史文化资源成为全社会的行动! 相似文献
903.
Sources of burnable material within U.S. cities are analyzed. Based on a detailed evaluation of construction practices, storage of burnable contents, building function and layout, and density of buildings in city districts, we derive urban fuel load densities in terms of land use type and geographic location. Residential building fuel loads vary regionally from 123 to 150 kg m–2; non-residential building classes have loads from 39 to 273 kg m–2. The results indicate that average U.S. urban area fuel loads range from 14 to 21 kg m–2. 相似文献
904.
905.
Jamneala T Small M Ruby R Larson JD 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2008,55(10):2320-2326
We discuss the operation of novel coupled-resonator filters with single-layer acoustic couplers. Our analysis employs the physical Mason model for acoustic resonators. Their simpler fabrication process is counterbalanced by the high acoustic attenuation of suitable coupler materials. At high levels of attenuation, both the phase and the acoustic impedance must be treated as complex quantities to accurately predict the filter insertion loss. We demonstrate that the typically poor near-band rejection of coupled resonator filters can be improved at the die level by connecting a small capacitance between the input and output of the filter to produce a pair of tunable transmission minima. We make use of these theoretical findings to fabricate coupled resonators filters operating at 2.45 GHz. 相似文献
906.
Polychlorinated biphenyls (PCBs) were produced in the mid 1900s for industrial use. The term PCBs refers to 209 theoretically possible chlorinated compounds of the biphenyl molecule (congeners). The number and location of the chlorines govern both the environmental fate and toxicity of each congener. Changes in the distribution of congeners in river sediments can result from congener transformation and/or preferential congener transport. This study exploits the distribution of PCB congeners, specifically congeners that maintain a constant ratio relationship in the commercially manufactured PCB mixtures (Aroclors), to quantify the likelihood of congener distribution shifts in river sediment. By using relative abundances, the influence of total PCB bias is eliminated. Correlated congeners (tracker pairs) maintain a constant relative proportion in sequentially more-highly chlorinated Aroclors, thus there is no need to know the source contaminating Aroclors a priori. Using the Frame et al. database of Aroclor congener distributions, 276 pairs of correlated congeners, constructed from 95 individual congeners, are identified. A comparison study of Aroclors and Hudson River sediments included 218 of the 276 tracker pairs. Conclusive evidence of a shift in the congener proportions is found in 120 of the 218 cases, a much greater number than expected if no change in congener distribution had occurred. 相似文献
907.
V Prasanna TN Prabha RN Tharanathan 《Journal of the science of food and agriculture》2005,85(5):797-803
Mango (Mangifera indica L cv Alphonso) was found to contain three isoforms (I, II and III) of β‐galactosidase which, upon purification on Sephadex G‐200, had relative abundances of 44, 38 and 18%, respectively. The total specific activity increased from 20 to 727 µmol l?1 upon purification, representing a ~36‐fold increase with a recovery of 0.28 U U?1. The optimal pH for activity and stability were in the ranges 3.6–4.3 and 4–6.2, respectively. The optimal temperature for β‐galactosidase activity was between 42 and 47 °C with Tm in the range 45–51 °C. The Km for pNP‐β‐galactopyranoside was 0.98, 1.11 and 0.95 mM , and Vmax was 0.56, 0.53 and 0.35 µmol pNP min?1, respectively for isoforms I, II and III. Hg2+ caused strong inhibition, whereas galacturonic acid, galactose, xylose, fucose and mannose slightly inhibited the activity of β‐galactosidase isoforms. The apparent molecular weights by GPC were 78, 58 and 91 kDa for isoforms I, II and III, respectively. The ability of these isoforms to degrade the endogenous substrate (arabinogalactan) possibly suggests a role in pectin dissolution during tissue softening/fruit ripening. Copyright © 2004 Society of Chemical Industry 相似文献
908.
909.
910.
Sara Small Timothy S. Oh Leonidas C. Platanias 《International journal of molecular sciences》2022,23(23)
Despite many recent advances in treatment options, acute myeloid leukemia (AML) still has a high mortality rate. One important issue in optimizing outcomes for AML patients lies in the limited ability to predict response to specific therapies, duration of response, and likelihood of relapse. With evolving genetic characterization and improving molecular definitions, the ability to predict outcomes and long-term prognosis is slowly improving. The majority of the currently used prognostic assessments relate to molecular and chromosomal abnormalities, as well as response to initial therapy. These risk categories, however, do not account for a large amount of the variability in AML. Laboratory techniques now utilized in the clinic extend beyond bone marrow morphology and single gene sequencing, to next-generation sequencing of large gene panels and multiparameter flow cytometry, among others. Other technologic advances, such as gene expression analysis, have yet to demonstrate enough predictive and prognostic power to be employed in clinical medicine outside of clinical trials, but may be incorporated into the clinic in the future. In this review, we discuss the utility of current biomarkers, and present novel biomarker techniques and strategies that are in development for AML patients. Measurable residual disease (MRD) is a powerful prognostic tool that is increasingly being incorporated into clinical practice, and there are some exciting emerging biomarker technologies that have the potential to improve prognostic power in AML. As AML continues to be a difficult-to-treat disease with poor outcomes in many subtypes, advances in biomarkers that lead to better treatment decisions are greatly needed. 相似文献