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121.
Heuberger AL Broeckling CD Lewis MR Salazar L Bouckaert P Prenni JE 《Food chemistry》2012,135(3):1284-1289
The effect of temperature on non-volatile compounds in beer has not been well characterised during storage. Here, a metabolomics approach was applied to characterise the effect of storage temperature on non-volatile metabolite variation after 16weeks of storage, using fresh beer as a control. The metabolite profile of room temperature stored (RT) and cold temperature stored (CT) beer differed significantly from fresh, with the most substantial variation observed between RT and fresh beer. Metabolites that changed during storage included prenylated flavonoids, purines, and peptides, and all showed reduced quantitative variation under the CT storage conditions. Corresponding sensory panel observations indicated significant beer oxidation after 12 and 16weeks of storage, with higher values reported for RT samples. These data support that temperature affected beer oxidation during short-term storage, and reveal 5-methylthioadenosine (5-MTA) as a candidate non-volatile metabolite marker for beer oxidation and staling. 相似文献
122.
Valentino L Valenzuela V Botterud A Zhou Z Conzelmann G 《Environmental science & technology》2012,46(7):4200-4206
This paper discusses the environmental effects of incorporating wind energy into the electric power system. We present a detailed emissions analysis based on comprehensive modeling of power system operations with unit commitment and economic dispatch for different wind penetration levels. First, by minimizing cost, the unit commitment model decides which thermal power plants will be utilized based on a wind power forecast, and then, the economic dispatch model dictates the level of production for each unit as a function of the realized wind power generation. Finally, knowing the power production from each power plant, the emissions are calculated. The emissions model incorporates the effects of both cycling and start-ups of thermal power plants in analyzing emissions from an electric power system with increasing levels of wind power. Our results for the power system in the state of Illinois show significant emissions effects from increased cycling and particularly start-ups of thermal power plants. However, we conclude that as the wind power penetration increases, pollutant emissions decrease overall due to the replacement of fossil fuels. 相似文献
123.
Fluorescence tracking of dissolved and particulate organic matter quality in a river-dominated estuary 总被引:6,自引:0,他引:6
CL Osburn LT Handsel MP Mikan HW Paerl MT Montgomery 《Environmental science & technology》2012,46(16):8628-8636
Excitation-emission matrix (EEM) fluorescence was combined with parallel factor analysis (PARAFAC) to model base-extracted particulate (POM) and dissolved (DOM) organic matter quality in the Neuse River Estuary (NRE), North Carolina, before and after passage of Hurricane Irene in August 2011. Principle components analysis was used to determine that four of the PARAFAC components (C1-C3 and C6) were terrestrial sources to the NRE. One component (C4), prevalent in DOM of nutrient-impacted streams and estuaries and produced in phytoplankton cultures, was enriched in the POM and in surface sediment pore water DOM. One component (C5) was related to recent autochthonous production. Photoexposure of unfiltered Neuse River water caused an increase in slope ratio values (S(R)) which corresponded to an increase in the ratio C2:C3 for DOM, and the production of C4 fluorescence in both POM and DOM. Changes to the relative abundance of C4 in POM and DOM indicated that advection of pore water DOM from surface sediments into overlying waters could increase the autochthonous quality of DOM in shallow microtidal estuaries. Modeling POM and DOM simultaneously with PARAFAC is an informative technique that is applicable to assessments of estuarine water quality. 相似文献
124.
Metal-organic framework materials as chemical sensors 总被引:1,自引:0,他引:1
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127.
Jackson LS Beacham-Bowden T Keller SE Adhikari C Taylor KT Chirtel SJ Merker RI 《Journal of food protection》2003,66(4):618-624
Patulin is a mycotoxin produced primarily by Penicillium expansum, a mold responsible for rot in apples and other fruits. The growth of this fungus and the production of patulin are common in fruit that has been damaged. However, patulin can be detected in visibly sound fruit. The purpose of this project was to determine how apple quality, storage, and washing treatments affect patulin levels in apple cider. Patulin was not detected in cider pressed from fresh tree-picked apples (seven cultivars) but was found at levels of 40.2 to 374 microg/liter in cider pressed from four cultivars of fresh ground-harvested (dropped) apples. Patulin was not detected in cider pressed from culled tree-picked apples stored for 4 to 6 weeks at 0 to 2 degrees C but was found at levels of 0.97 to 64.0 microg/liter in cider pressed from unculled fruit stored under the same conditions. Cider from controlled-atmosphere-stored apples that were culled before pressing contained 0 to 15.1 microg of patulin per liter, while cider made from unculled fruit contained 59.9 to 120.5 microg of patulin per liter. The washing of ground-harvested apples before pressing reduced patulin levels in cider by 10 to 100%, depending on the initial patulin levels and the type of wash solution used. These results indicate that patulin is a good indicator of the quality of the apples used to manufacture cider. The avoidance of ground-harvested apples and the careful culling of apples before pressing are good methods for reducing patulin levels in cider. 相似文献
128.
Elder abuse is a concerning issue for professional psychologists, who have legal and ethical obligations to report it. While dramatic cases of abuse are easy to identify, psychologists may struggle with how to respond to more subtle cases of potential abuse. General legal standards for elder abuse reporting are provided, along with ethical guidelines from the APA Ethics Code. Important considerations are discussed in tandem with three fictional vignettes illustrating examples of suspected elder abuse that professional psychologists may more commonly confront in practice. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
129.
Du Rocher Schudlich Tina D.; Papp Lauren M.; Cummings E. Mark 《Canadian Metallurgical Quarterly》2011,25(4):531
This study investigated longitudinal relations between spouses' depressive symptoms and styles of conflict resolution displayed by husbands and wives in marital conflict, including angry, depressive, and constructive patterns of expression. Behavioral observations were made from a community sample of 276 couples during marital conflict resolution tasks once a year for 3 years. Couples were observed engaging in a major and minor conflict resolution task. Constructive, angry, and depressive conflict resolution styles were derived from the behavioral observation coding. Couples self-reported on depressive symptoms and marital dissatisfaction. Path analyses provided support for an extension of the marital discord model of depression (Beach, Sandeen, & O'Leary, 1990). Specifically, angry, depressive, and constructive styles of conflict each mediated the link between marital dissatisfaction and depressive symptoms. Significant cross-spouse effects were found. Implications for the treatment of depressed and/or relationally discordant couples are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
130.
Environmentally sustainable building construction has experienced significant growth during the past 10 years. The public is becoming more aware of the benefits of green construction as prominent politicians, celebrities, documentarians, and journalists highlight the built environment’s impact on greenhouse gas emissions and natural resource consumption. Other factors, including higher energy prices, increased costs of building materials, and regulatory incentives, are also pushing the green building market to grow and expand. However, barriers to green building continue to exist, including the ability to deliver a green project within acceptable cost constraints. In order for project managers to deliver sustainable construction according to clients’ cost expectations, modifications must be made to traditional project management processes and practices. The objective of this paper is to suggest specific modifications to conventional building practices to optimize the delivery of cost-efficient green building projects. This paper presents an overview of research related to the costs and trends of green building and uses these research findings to make recommendations for greening project management practices for the construction industry. Our research results show that greening project management practices can add significant value to a sustainable construction project while delivering it within acceptable cost constraints. A detailed analysis using matrix present specific adjustments to traditional project management practices, with a premise that a green project improves its chances for financial success if a cross-discipline team is involved at the earliest stages and throughout the project. 相似文献