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121.
Uta Schwietzke Jessica Malinowski Katja Zerge Thomas Henle 《European Food Research and Technology》2011,233(2):243-251
To obtain basic information about the extent of the early Maillard reaction in commercially available cheese varieties of
varying degrees of maturity, Amadori products (APs) formed between reducing sugars and the ε-amino group of lysine (ε-APs)
or the α-amino of selected amino acids (α-APs) were analyzed. APs were determined as the corresponding N-(2-furoylmethyl) amino acids (FMAAs) after acid hydrolysis using RP–HPLC with UV-detection as well as mass spectroscopy.
Identification of the FMAAs resulting from the α-APs of lysine, valine, leucine, and isoleucine was achieved for the first
time for cheese samples. The content of furosine, which is a hallmark for ε-APs, ranged from to 3–75 mg/100 g protein corresponding
to 24–591 μmol ε-AP/100 g protein. ε-AP levels declined during ripening in all investigated cheeses, depending on the cheese
type and stage of maturation. The mean content of four α-APs ranged from 138 to 681 μmol/100 g protein. Lowest concentrations
were found in long-term ripened cheese samples, indicating a putative degradation of α-APs and ε-APs during advanced stages
of maturation. The ratio of α-APs to ε-APs might be a useful indicator of cheese ripening. 相似文献
122.
The United Nations High Commissioner for Refugees (UNHCR) establishes and maintains refugee camps to meet the needs of 34.5
million people affected by disaster or war worldwide. Like other international humanitarian organizations, UNHCR maintains
central stockpiles which supply these refugee operations. Management at UNHCR seeks to improve the timeliness and quality
of its disaster response subject to its budget constraints. We develop an inventory model to analyze the interaction between
a stockpile and a downstream refugee camp or relief operation. We consider two inventory decisions: first, how to partition
a fixed budget between stockpiling and shipping costs in order to best meet the needs of beneficiaries; and second, given
the shipping budget determined by the budget partition, how to ship relief items from the stockpile to a downstream relief
operation in an efficient manner. We solve for the shipment policy using dynamic programming, then determine the optimal stockpile
size given knowledge of the optimal shipment policy. The optimization balances a key tradeoff: a larger stockpile is costly
to procure and maintain, but enhances a humanitarian organization’s ability to respond to relief operation demands. We provide
insights into shipment strategies and stockpile size. We also develop a spreadsheet model to help humanitarian organizations
in their operational decision-making, leading to improved response to beneficiaries. Humanitarian organizations must use their
financial resources wisely to carry out their mandates, and models of this type can help them make the best use of their limited
response resources. 相似文献
123.
P. Juslin and H. Olsson's (see record 1997-03612-006) distinction between Thurstonian and Brunswikian uncertainty is examined and their sampling model of sensory discrimination analyzed as a representative of the class of memoryless decision processes. The separate characteristics and combined behavior of 4 main components of the model are explored: (a) the basic decision process, (b) the assumption of deadline responding, (c) the moving window model of memory, and (d) the hypothesized basis for confidence. It is argued that grafting a moving window memory onto a memoryless decision process has several undesirable consequences. Moreover, the suggested basis for confidence leads to predictions that are counterintuitive and unsupported by empirical evidence. It is concluded that the window-sampling model is a maladapted combination of inappropriate elements, which is implausible as a model of decision making, memory, or confidence, in sensory discrimination. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
124.
Cigarette smoking among college students is prevalent and correlated with other unhealthy behaviors. Reinforced abstinence (e.g., contingency management) has been demonstrated to be an effective method for reducing substance use in a variety of populations and across a variety of drugs, including cigarettes. Reinforced abstinence has seldom been used specifically targeting a college student population. A Brief Abstinence Test (BAT) has been used to effectively reduce cocaine use among methadone maintenance patients (Robles, Silverman, Preston, Cone, Katz, Bigelow, & Stitzer, 2000). However, no published studies have investigated the use of a BAT to reduce the use of cigarettes. The current study implemented a 3-week intervention (Baseline 1, BAT, and Baseline 2 weeks) for smoking abstinence among college students. Forty-two percent of the sample met abstention criteria during the BAT. Carbon monoxide and urinalysis scores decreased significantly from Baseline 1 to the BAT phase but did not differ significantly from BAT to Baseline 2. These results suggest that the BAT may have utility initiating abstinence in both clinical and research contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
In 2008, the UK launched the first regulatory sustainability reporting scheme for biofuels. The development of the scheme, managed by the Low Carbon Vehicle Partnership for the Department for Transport, involved extensive stakeholder engagement. The scheme has significantly increased understanding by policy-makers, the biofuels industry and its supply chains on how to monitor and manage the sustainability risks of biofuels and increase their greenhouse-gas benefits. It is providing a practical model for similar developments globally. To receive certificates in order to meet volume obligations under the Renewable Transport Fuel Obligation (RTFO), suppliers must provide a monthly carbon and sustainability report on individual batches of renewable fuels they supply into the UK. The Renewable Fuels Agency produces aggregate monthly reports of overall performance and quarterly updates of individual supplier performance. This scheme is an important first step to assist the biofuels industry to demonstrate its environmental credentials and justify the subsidies received. The paper provides a case study of the development of the scheme, its initial outcomes and outstanding challenges. 相似文献
126.
Isham Eve A.; Banks William P.; Ekstrom Arne D.; Stern Jessica A. 《Canadian Metallurgical Quarterly》2011,37(5):1458
Previous work suggested the association between intentionality and the reported time of action was exclusive, with intentionality as the primary facilitator to the mental time compression between the reported time of action and its effect (Haggard, Clark, & Kalogeras, 2002). In three experiments, we examined whether mental time compression could also be observed in an unintended action. Participants performed an externally cued key press task that elicited one of two possible tones. The reported time of action shifted closer to the tone when the tone was used to indicate the winner of a race (Exp.2) compared to when the tone was meaningless and did not indicate winning (Exp.1). This suggests that reported time of an unintended action could shift toward the effect in some contexts. Furthermore, the results from Exp.2 and Exp.3 (tones were substituted with verbal feedback) showed that a presumed winning action was judged to occur earlier whereas a presumed losing action was judged to be later. These findings therefore support the view that the reported time of action is reconstructed from known temporal information rather than determined by intentionality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
127.
Piguet Olivier; Connally Emily; Krendl Anne C.; Huot Jessica R.; Corkin Suzanne 《Canadian Metallurgical Quarterly》2008,23(2):307
Memory is susceptible to distortions. Valence and increasing age are variables known to affect memory accuracy and may increase false alarm production. Interaction between these variables and their impact on false memory was investigated in 36 young (18-28 years) and 36 older (61-83 years) healthy adults. At study, participants viewed lists of neutral words orthographically related to negative, neutral, or positive critical lures (not presented). Memory for these words was subsequently tested with a remember-know procedure. At test, items included the words seen at study and their associated critical lures, as well as sets of orthographically related neutral words not seen at study and their associated unstudied lures. Positive valence was shown to have two opposite effects on older adults' discrimination of the lures: It improved correct rejection of unstudied lures but increased false memory for critical lures (i.e., lures associated with words studied previously). Thus, increased salience triggered by positive valence may disrupt memory accuracy in older adults when discriminating among similar events. These findings likely reflect a source memory deficit due to decreased efficiency in cognitive control processes with aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
128.
Tsai Jessica Chia-Chin; Knoblich Günther; Sebanz Natalie 《Canadian Metallurgical Quarterly》2011,37(5):1407
According to ideomotor theories, perceiving action effects produced by others triggers corresponding action representations in the observer. We tested whether this principle extends to actions performed by externally controlled limbs and tools. Participants performed a go–no-go version of a spatial compatibility task in which their own actions resulted in the movement of a limb or tool, whereas a second, externally controlled limb or tool was seen performing a complementary go–no-go task. Spatial compatibility effects, indicating inclusion of the externally controlled effector in action planning, were observed when the externally controlled limb was identical to the controlled limb (Experiment 1) and when actions of limbs and tools (Experiment 2) or pairs of tools (Experiment 3 and 4) were combined according to participants' motor experience. When participants acted together, controlling a tool each, spatial compatibility effects occurred regardless of motor experience (Experiment 5). These findings demonstrate that (a) externally controlled tool actions are included in action planning and (b) social context modulates how externally controlled actions are mapped onto action representations. Implications of these findings for theories of perception–action links and object processing are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
129.
Psyllium husks were treated with different concentrations of HCl in ethanol at ambient temperature to improve their gelling and water uptake properties. The acid-treated psyllium samples were examined and compared to the control, which was subjected to the same procedure without acid treatment, for their gelling properties, water uptake capacities, swelling volumes, and bile acid-binding capacities. The results showed that 0.36–1.44% HCl treatment in ethanol may significantly decrease the gelling, water uptake, and swelling capacities of psyllium without reducing their bile acid-binding abilities. Scanning electron microscopic (SEM) analysis showed that HCl treatment might reduce surface area of psyllium particle, which might contribute to their reduced water uptake capacity. The results from this study suggest that low concentration acid treatment in ethanol may improve psyllium functionality. 相似文献
130.
Ruffolo Jessica Somerville; Javorsky Debbie J.; Tremont Geoffrey; Westervelt Holly James; Stern Robert A. 《Canadian Metallurgical Quarterly》2001,13(3):299
The Rey-Osterrieth Complex Figure (ROCF) is commonly used to assess visuospatial skills, visuoconstruction, visual memory, and executive functioning. Two different methods are traditionally used to record the order in which the figure is drawn: the flowchart method and the pen-switching method. Although it has been suggested that pen switching may interfere with performance, to date no research has been conducted to assess whether ROCF performance significantly differs due to administration method. As part of routine neuropsychological evaluation, 100 inpatients and outpatients were randomly assigned to either method. Using the Boston Qualitative Scoring System and the traditional 36-point scoring method, the authors unexpectedly found that the pen-switching group generally performed better than the flowchart group, and productions drawn with pen switching were also significantly faster to score. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献