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141.
Micellarisation of Carotenoids from Raw and Cooked Vegetables   总被引:1,自引:0,他引:1  
The efficiency of carotenoid micellarisation from plant foods can be used as an effective tool for the initial screening of carotenoid bioavailability. Therefore, the objectives of the present study were to assess the effects of cooking on the micellarisation of beta-carotene, lycopene, beta-cryptoxanthin and lutein from courgette (zucchini), red pepper and tomato; and, to a minor extent, investigate uptake of lutein by Caco-2 cells from micellar fractions obtained from raw and cooked courgettes. Both raw and cooked vegetables were subjected to an in vitro digestion procedure. beta-Carotene levels were significantly decreased in the digesta from each vegetable after boiling, grilling, microwave-cooking, or steaming, however all of the cooking methods enhanced beta-carotene transfer to micelles. Carotenoid micellarisation ranged from 1.7% to 100% depending on the food, carotenoid, and the cooking method tested. Grilling and microwave-cooking were generally the most detrimental on the transfer of xanthophyll carotenoids, namely beta-cryptoxanthin, to the micelles. Caco-2 cells absorbed greater amounts of lutein from the micelles of microwave-cooked courgettes than those that were raw, boiled, grilled, or steamed. Depending on the cooking methods used, carotenoid retention as well as micellarisation varied for each carotenoid among the different vegetables and different carotenoids present in each particular food.  相似文献   
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ABSTRACT: During abattoir meat inspection pig carcasses are partially or fully condemned upon detection of disease that poses a risk to public health or welfare conditions that cause animal suffering e.g. fractures. This incurs direct financial losses to producers and processors. Other health and welfare-related conditions may not result in condemnation but can necessitate 'trimming' of the carcass e.g. bruising, and result in financial losses to the processor. Since animal health is a component of animal welfare these represent a clear link between suboptimal pig welfare and financial losses to the pig industry.Meat inspection data can be used to inform herd health programmes, thereby reducing the risk of injury and disease and improving production efficiency. Furthermore, meat inspection has the potential to contribute to surveillance of animal welfare. Such data could contribute to reduced losses to producers and processors through lower rates of carcass condemnations, trimming and downgrading in conjunction with higher pig welfare standards on farm. Currently meat inspection data are under-utilised in the EU, even as a means of informing herd health programmes. This includes the island of Ireland but particularly the Republic.This review describes the current situation with regard to meat inspection regulation, method, data capture and utilisation across the EU, with special reference to the island of Ireland. It also describes the financial losses arising from poor animal welfare (and health) on farms. This review seeks to contribute to efforts to evaluate the role of meat inspection as a surveillance tool for animal welfare on-farm, using pigs as a case example.  相似文献   
144.
Type II heat-labile enterotoxins (LT-II) have been reported in Escherichia coli isolates from humans, animals, food and water samples. The goal here was to determine the specific roles of the antigenically distinguishable LT-IIa and LT-IIb subtypes in pathogenesis and virulence of enterotoxigenic E. coli (ETEC) which has not been previously reported. The prevalence of genes encoding for LT-II was determined by colony blot hybridization in a collection of 1648 E. coli isolates from calves and pigs with diarrhea or other diseases and from healthy animals. Only five isolates hybridized with the LT-II probe and none of these isolates contained genes for other enterotoxins or adhesins associated with porcine or bovine ETEC. Ligated intestinal loops in calves, pigs, and rabbits were used to determine the potential of purified LT-IIa and LT-IIb to cause intestinal secretion. LT-IIa and LT-IIb caused significant secretion in the intestinal loops in calves but not in the intestinal loops of rabbits or pigs. In contrast, neonatal pigs inoculated with isogenic adherent E. coli containing the cloned genes for LT-I, LT-IIa or LT-IIb developed severe watery diarrhea with weight loss that was significantly greater than pigs inoculated with the adherent, non-toxigenic parental or vector only control strains. The results demonstrate that the incidence of LT-II appeared to be very low in porcine and bovine E. coli. However, a potential role for these enterotoxins in E. coli-mediated diarrhea in animals was confirmed because purified LT-IIa and LT-IIb caused fluid secretion in bovine intestinal loops and adherent isogenic strains containing cloned genes encoding for LT-IIa or LT-IIb caused severe diarrhea in neonatal pigs.  相似文献   
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The occurrence and distribution of culturable fungi in Taylor Valley, Antarctica was assessed in terms of soil habitat. Soil transects throughout the valley revealed differential habitat utilization between filamentous and non-filamentous (yeast and yeast-like) fungi. In addition, there were significant differences in species distribution patterns with respect to soil pH, moisture, distance from marine coastline, carbon, chlorophyll a, salinity, elevation and solar inputs. Filamentous fungal abundance is most closely associated with habitats having higher pH, and soil moistures. These close associations were not found with yeast and yeast-like fungi demonstrating that yeast and yeast-like fungi utilize a broader range of habitat. An intensive survey of the Victoria Land is necessary to gain a better understanding of their role in soil functioning and nutrient cycling processes.  相似文献   
147.
Urbanisation has proved seemingly inexorable in the island Pacific in recent decades, yet has largely escaped critical attention. Urban growth has been associated with civil unrest, unemployment, crime, poverty, environmental degradation, traffic congestion (and heightened inequality), inadequate formal housing provision, the rise of the informal sector (and repressions of it), pressures on education, housing, health and other services such as water and garbage disposal, rather than with sustained economic growth. Such wide‐ranging issues have posed problems where economic growth is static, structures of urban governance are lacking or weak (or corrupt), land disputes are frequent and urban populations increasingly permanent. Urban development necessitates balanced regional development and sustainable urbanisation or the future will lie elsewhere.  相似文献   
148.
Access to health care in developing countries, the main destinations of medical tourists, is notoriously uneven, and often becoming more so. Medical tourism, urban bias and privatisation have combined to exacerbate this trend. This is exemplified in both Thailand and India, where regional areas have been disadvantaged by the migration of health-care workers to hospitals focusing on medical tourism, neo-liberal national financial provision for medical tourism (and related tourism campaigns) and evidence of trickle-down gains is lacking. Medical tourism challenges rather than complements local health care providers, distorts national health care systems, and raises critical national economic, ethical and social questions.  相似文献   
149.
Hourly pedometer counts and irregularly measured concentration of the hormone progesterone were available for a large number of dairy cattle. A hidden semi-Markov was applied to this bivariate time-series data for the purposes of monitoring the reproductive status of cattle. In particular, the ability to identify oestrus is investigated as this is of great importance to farm management. Progesterone concentration is a more accurate but more expensive method than pedometer counts, and we evaluate the added benefits of a model that includes this variable. The resulting model is biologically sensible, but validation is difficult. We utilize some auxiliary data to demonstrate the model’s performance.  相似文献   
150.
Black-tailed prairie dogs (Cynomys ludovicianus) have high dietary overlap with livestock, which can cause forage-centric conflicts between agriculture and conservation. Research suggests prairie dogs can enhance forage quality, but trade-offs between quality and quantity throughout the growing season remain unclear, as well as the degree to which increased forage quality is caused by altered species composition versus altered plant physiology. To assess the effects of prairie dog herbivory on forage in a northern mixed-grass prairie, we collected samples on prairie dog colonies and at sites without prairie dogs during June, July, and August 2016 - 2017 for forage quality, and August 2015 - 2017 for herbaceous biomass. To isolate mechanisms affecting forage quality, we collected both composite samples of all herbaceous species and samples of western wheatgrass (Pascopyrum smithii [Rydb.] Á. Löve). Across years and plant sample types, crude protein, phosphorus, and fat were 12-44% greater and neutral detergent fiber was 6-10% lower on prairie dog colonies than at sites without prairie dogs. The effects of prairie dogs on forage quality persisted throughout the season for western wheatgrass samples (all treatment*time p-values ≥ 0.4). Across years, aboveground herbaceous biomass did not differ significantly between prairie dog colonies and sites without prairie dogs (on-colony: 933 ± 156 kg/ha, off-colony: 982 ± 117 kg/ha). The effects of prairie dogs on herbaceous biomass were significantly influenced by spring precipitation. In years with dry springs, herbaceous biomass was lower on colonies than sites without prairie dogs and this pattern was reversed in years with wet springs. Our results demonstrate season-long enhanced forage quality on prairie dog colonies, indicating that multiple mechanisms are shaping forage quality in this system, including altered species composition, phenological growth stage, and soil condition. Across years, enhanced forage quality may help to offset reductions in forage quantity for agricultural producers.  相似文献   
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