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31.
We previously demonstrated that postmortem water buffalo meat had higher tenderness than Brahman beef. In order to explain this difference in tenderness, the objective of the current study was to investigate the protease activity in these two meats. Five female crossbred water buffalo (Philippine Carabao×Bulgarian Murrah) and five female crossbred cattle (Brahman×Philippine Native) were slaughtered at 30months of age, followed by immediate sampling of Longissimus thoracis muscle for measurement of protease activity. Results showed that buffalo meat had significantly higher protease activity compared to beef (P<0.05). Furthermore, calpain inhibitor 1, a specific inhibitor of calpains 1 and 2, was the most effective inhibitor of protease activity. There was no difference in calpastatin activity, and no major differences were observed in calpains 1, 2, and calpastatin expression by Western blotting. This study suggests that higher calpain activity in early postmortem buffalo meat was responsible for the increased tenderness of water buffalo meat compared to beef.  相似文献   
32.
In the present study the accumulation potentials in earthworms (Eisenia fetida) of selected brominated flame retardants (BFRs) were investigated. The tested BFRs, including polybrominated diphenyl ethers (PBDEs), hexabromobenzene (HBB), and 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), were found to be bioavailable to Eisenia fetida, and they accumulated in the earthworms. To our knowledge, this is the first published study to address the bioaccumulation potential of TBECH in terrestrial biota. Aging the soil resulted in decreased accumulation of TBECH, HBB, and PBDEs with six or less bromine atoms. However, no effect of soil aging was seen for BDEs 183 or 209, possibly due to their low mobility in soil. The use of different soils (artificial OECD soil and two natural Swedish soils) also affected the degree of accumulation in the worms. The results indicate that use of the generally accepted standard OECD soil may overestimate accumulation of organic contaminants by earthworms, due to high bioavailability of the contaminants and/or weight loss of the worms in it. Further, the accumulation of selected PBDEs and HBB was compared to the accumulation of their chlorinated analogues. Brominated compounds accumulated to the same or a lesser extent than their chlorinated counterparts.  相似文献   
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34.
Analysis of arsenic concentrations in New Jersey well water from the Newark Basin showed up to 15% of the wells exceed 10 microg L(-1), with a maximum of 215 microg L(-1). In some geologic settings in the basin, this mobile arsenic could be from the weathering of pyrite (FeS2) found in black shale that contains up to 4% arsenic by weight. We hypothesized that under oxic conditions at circumneutral pH, the microbially mediated oxidation of sulfide in the pyrite lattice would lead to the release of pyrite-bound arsenic. Moreover, the oxidation of aqueous As(III) to As(V) by aerobic microorganisms could further enhance arsenic mobilization from the solid phase. Enrichment cultures under aerobic, As(III)-oxidizing conditions were established under circumneutral pH with weathered black shale from the Newark Basin as the inoculum source. Strain WAO, an autotrophic inorganic-sulfur and As(III)-oxidizer, was isolated and phylogenetically and physiologically characterized. Arsenic mobilization studies from arsenopyrite (FeAsS) mineral, conducted with strain WAO at circumneutral pH, showed microbially enhanced mobilization of arsenic and complete oxidation of released arsenic and sulfur to stoichiometric amounts of arsenate and sulfate. In addition, WAO preferentially colonized pyrite on the surface of arsenic-bearing, black shale thick sections. These findings support the hypothesis that microorganisms can directly mobilize and transform arsenic bound in mineral form at circumneutral pH and suggest that the microbial mobilization of arsenic into groundwater may be important in other arsenic-impacted aquifers.  相似文献   
35.
Proxies and measurement techniques for mineral dust in Antarctic ice cores   总被引:1,自引:0,他引:1  
To improve quantitative interpretation of ice core aeolian dust records, a systematic methodological comparison was made. This involved methods for water-insoluble particle counting (Coulter counter and laser-sensing particle detector), soluble ion analysis (ion chromatography and continuous flow analysis), elemental analysis (inductively coupled plasma mass spectroscopy at pH 1 and after full acid digestion), and water-insoluble elemental analysis (proton induced X-ray emission). Antarctic ice core samples covering the last deglaciation from the EPICA Dome C (EDC) and the EPICA Dronning Maud Land (EDML) cores were used. All methods correlate very well among each other, but the ratios of glacial age to Holocene concentrations, which are typically a factor approximately 100, differ between the methods by up to a factor of 2 with insoluble particles showing the largest variability. The recovery of ICP-MS measurements depends on the digestion method and is differentfor different elements and during different climatic periods. EDC and EDML samples have similar dust composition, which suggests a common dust source or a common mixture of sources for the two sites. The analyzed samples further reveal a change of dust composition during the last deglaciation.  相似文献   
36.
Two studies of retail fresh, ripened and semi-hard cheeses made from raw, thermized or pasteurized milk were undertaken in the UK during 2004 and 2005 to determine the microbiological quality of these products. Using microbiological criteria in European Commission Recommendations 2004/24/EC and 2005/175/EC, 2% of both raw, thermized (37/1819 samples) and pasteurized (51/2618 samples) milk cheeses were of unsatisfactory quality. Raw or thermized milk cheeses were of unsatisfactory quality due to levels of Staphylococcus aureus at 10(4)cfu g(-1), Escherichia coli at 10(5)cfu g(-1), and/or Listeria monocytogenes at 10(2)cfu g(-1), whereas pasteurized milk cheeses were of unsatisfactory quality due to S. aureus at 10(3)cfu g(-1) and/or E. coli at 10(3)cfu g(-1). Salmonella was not detected in any samples. Cheeses were of unsatisfactory quality more frequently when sampled from premises rated as having little or no confidence in management and control systems, and stored/displayed at above 8 degrees C. Raw or thermized milk cheeses were also more likely to be of unsatisfactory quality when they were unripened types, and pasteurized milk cheeses when they were: semi-hard types; from specialist cheese shops or delicatessens; cut to order. These results emphasize the need for applying and maintaining good hygiene practices throughout the food chain to prevent contamination and/or bacterial growth. Labelling of cheeses with clear information on whether the cheese was prepared from raw milk also requires improvement.  相似文献   
37.
Stillbirth, defined as a calf that dies just prior to, during, or within 48 h of parturition, represents a reoccurring concern among breeders of dairy cattle in the United States. About 11% of parturitions of primiparous Holstein cows result in the death of a calf; 5.7% in multiparous cows. Genetic evaluations can be reported as perinatal survival to 48 h to emphasize the positive information about the trait. The purpose of this research was to: 1) estimate genetic parameters by restricted maximum likelihood for perinatal survival rates; 2) characterize the genetic evaluation of sires for the perinatal survival of their progeny and maternal grandsires for the perinatal survival of their daughters progeny; and 3) estimate genetic trends from 1984 to 1994. Data (n = 666,339) were from the National Association of Animal Breeders calving ease database. Over 600 new young sires were available each year. The binomial response variable, 1 = alive, 0 = stillborn within 48 h of parturition was analyzed by using a sire-maternal grandsire linear mixed model. The model included fixed effects for sex of calf, dystocia, and season of birth, and gestation length as a covariate; correlated random effects of sire and maternal grandsire; and uncorrelated random effects of herd-years. Parturitions of primiparous and multiparous cows were analyzed separately. In primiparous cows, heritability estimates were 1.1 and 2.2% for sire of the calf and maternal grandsire, respectively. The genetic correlation between sire and maternal grandsire predicted transmitting ability (PTA) for perinatal survival, was 0.31; simple product moment correlations among sire-MGS PTA were 0.43 and 0.46 for primiparous and multiparous cows, respectively. The PTA for sire of the calf ranged from -2.9 (lower survival) to 2.8% (higher survival). Mean PTA from 1984 to 1994 was quite variable from year to year. Evidence showed a slightly negative, but nonsignificant, genetic trend in perinatal survival (-0.04% per year for sires and -0.02% per year for maternal grandsires). Estimates of genetic parameters and genetic trends for data from multiparous cows are also reported. Correlations among PTA for perinatal survival, milk yield, and calving ease are given.  相似文献   
38.
BACKGROUND: A major factor influencing tobacco use is its price. Fiscal policies on tobacco are a key ingredient of any comprehensive control strategy, as they can be used to raise prices. The European Union (EU) developed directives to ensure some harmonisation of the fiscal pressure on tobacco across its member states. OBJECTIVES: To provide a simple comparison of tobacco prices in the EU, adjusting for the purchasing power of each currency. DESIGN: For price comparisons, a 20 units pack of Marlboro was the reference product, and data refer to April 2000. Purchasing power parities (PPP) for each member state currency have been compiled. These are currency conversion rates, which convert to a common currency and equalise the purchasing power of different currencies. MAIN OUTCOME MEASURES: Nominal prices of a Marlboro pack for each member state, and a price index, estimated taking as reference the EU mean. Adjusted prices and an adjusted price index have been estimated using PPP. RESULTS: Nominal prices show wide variation, with the cheapest pack in Portugal (59) and the most expensive in the UK (196); the range of variation is three-fold. However, PPP adjusted prices reveal a different distribution. In three countries adjusted prices are outliers, but all other countries make two clusters, one around the average EU index of 100, the other around a lower value of 85. CONCLUSIONS: These results suggest that fiscal harmonisation policies in the EU do not have an even effect at reducing availability by its impact in price.  相似文献   
39.
The efficacy of sucrose combined with CaCl2 during osmotic dehydration (OD) was tested for the control of Botrytis cinerea, Colletotrichum acutatum, and Penicillium expansum growth on lightly processed apple slices. The objective of this work was to determine whether the addition of CaCl2 in the osmotic solutions would limit the proliferation of fungal decay organisms. Slices were submitted to OD for 1 h at 25 degrees C in solutions containing 5 to 65% sucrose. Calcium chloride was added to a similar set of sucrose solutions at 0 to 8%. Control slices were made of untreated slices, and slices were processed in water. The mass ratio of the slices did not vary when fruit pieces were processed in solutions containing 5 to 65% sucrose. These slices showed a high susceptibility to spoilage compared to the control slices not submitted to OD: a significant twofold and 60% increase in decay area caused by B. cinerea and P. expansum, respectively, was observed when slices were processed in 50% sucrose/0% CaCl2; C. acutatum showed a significant 50% increase in decay area when slices were processed in 20% sucrose/0% CaCl2. Calcium uptake was significantly increased when slices were processed in CaCl2 solutions, and the highest Ca content was observed when processed in 8% CaCl2, reaching 40 times that of the control slices processed in water. Calcium-treated slices were less susceptible to spoilage by all three pathogens, and the most effective combination in reducing apple slice spoilage was 20 to 30% sucrose combined with 2% CaCl2.  相似文献   
40.
引言近年来汽车制造业正面临着一个迅速变革的时期。为达到所要求的节约燃料的目的。必需降低车辆的重量。这就要求汽车的各种部件在规格和结构上来一个变化,作为控制汽车平稳性能的悬挂装置的衬套就是这些部件之一例。  相似文献   
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