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The objective was to examine the effect of the additives acetic acid, lactic acid, sodium bicarbonate, sodium chloride, and sodium hydroxide on the hydrolysis of whey protein isolate with subcritical water. A screening experimental design was used to study the effect of temperature, time, and additives. The most influential additive, sodium bicarbonate, along with temperature and time was used in a second experimental design to predict the treatment conditions to maximize the degree of hydrolysis and production of free amino acids. The maximum degree of hydrolysis achieved was 50% at a concentration of 1.24 M sodium bicarbonate, 291 °C, and 28 min. The highest concentration of total amino acids was 83.0 mg/g of whey protein isolate with 0.83 M sodium bicarbonate at 264 °C for 29 min. Compared to water alone, sodium bicarbonate increased the degree of hydrolysis 4-fold and the production of amino acids by 44% and decreased peptides' molecular weight.  相似文献   
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Landscape Ecology - Landscape modification alters the condition of ecosystems and the structure of terrain, with widespread impacts on biodiversity and ecosystem functioning. Seafloor dredging...  相似文献   
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The Drought Calculator (DC), a spreadsheet-based decision support tool, was developed to help ranchers and range managers predict reductions in forage production due to drought. Forage growth potential (FGP), the fraction of historical average production, is predicted as a weighted average of monthly precipitation from January through June. We calibrated and evaluated the DC tool in the Great Plains of the United States, using FGP and precipitation data from Colorado (CO), North Dakota (ND), and Wyoming (WY). In CO, FGP was most sensitive to precipitation in April and May, in ND to precipitation in April and June, and in WY to precipitation in April, May, and June. Weights in these months ranged from 0.16 to 0.52. Prediction was better for CO and WY than for ND. When January–June precipitation was used, the tool correctly predicted 83% of the years with FGP reduced by drought for CO, 82% for WY, and only 67% for ND. Positive values of the True Skill Statistic (0.53 for CO, 0.42 for WY, and 0.17 for ND) indicate that FGP was classified as above or below average better than random selection. Predicting FGP earlier than April in CO and WY will require accurate forecasts of April–June precipitation. Use of the DC is most limited by insufficient forage data to determine the site-specific relationships between FGP and monthly precipitation. Even so, the decision tool is useful for discriminating drought effects on FGP classification being above or below the long-term average, and it provides a quantitative prediction to producers for their destocking decisions in drought years.  相似文献   
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The immunocompromised are at particular risk for infection with zoonotic diseases. Persons can be temporarily immunocompromised due to pregnancy or developmental stage (i.e. infants); longer-term or permanent states of immunosuppression can occur as a result of immunosuppressive treatment following cancer or organ transplant, or from infectious diseases, such as AIDS. The focus of this review article is on emerging bacterial zoonotic diseases that are of particular concern among the immunocompromised. Factors that affect disease emergence can include factors such as human demographics and behavior; technology and industry; economic development and land use; international travel and commerce; microbial adaptation and change; and breakdown of public health measures. The immunocompromised need to take precautions when engaging in seemingly normal activities such as food preparation; caring for companion animals; and recreational or occupational activities. The immunocompromised are not only more susceptible to infection, but often suffer more serious sequelae as a result of infection. This review article provides an overview of the major foodborne, respiratory, and vector-borne bacterial pathogens that affect the immunocompromised. The major categories of immunodeficiency are described. In addition, measures that can be taken to prevent infection, including the role of health education, are discussed.  相似文献   
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