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81.
82.
Traffic congestion pricing is studied using a general-equilibrium framework that incorporates public goods expenditures, an income tax, a government budget constraint, and preferences for equity. Individuals differ with respect to wages, values of travel time, and the congestion characteristics of their vehicles. Formulae for optimal tolls are derived and decomposed to reveal the separate influences of individual and vehicle heterogeneity, road network effects, fiscal effects and equity concerns. Using an example various tolling regimes are considered, defined by how much of the network is tolled, by whether and how tolls are differentiated by route, and by vehicle and individual characteristics. 相似文献
83.
Hargous Carolina Venegas Reyes Marcela Taillie Lindsey Smith González Carmen Gloria Corvalán Camila 《Nutrition journal》2020,19(1):1-8
Nutritional treatment is one of the most important components of multidisciplinary anti-cancer therapy. Home enteral nutrition is considered as a safe procedure, however, it may be associated with the risk of side effects, such as nausea, vomiting, abdominal pain, and diarrhoea. It is uncertain whether diarrhoea is the result of the enteral formula administration or gut dysbiosis. One of the methods which may be used to alter the composition of gut microbiota is the administration of a probiotic strain. Lactobacillus plantarum 299v ingestion was found to diminish the adverse events of irritable bowel syndrome and Clostridium difficile infection - entities that share the symptoms with enteral nutrition side effects. Therefore, the primary aim of this study is to determine the effect of Lactobacillus plantarum 299v on prevention of weight loss of cancer patients receiving home enteral nutrition. The secondary aims are to evaluate the role of this probiotic strain in the improvement of nutritional status, enteral nutrition tolerance, and patients’ quality of life. Forty patients with cancer receiving home enteral nutrition will be enrolled in this clinical trial and randomized to receive one capsule of Lactobacillus plantarum 299v (Sanprobi IBS®) twice a day or placebo for 12 weeks in a double-blind manner. Laboratory tests (the level of albumin, total protein, transferrin, and total lymphocyte count), anthropometric parameters (body mass, the content of fat mass, muscle mass, and total body water), Nutritional Risk Screening (NRS 2002), enteral nutrition tolerance as well as quality of life will be measured. Measurements will be obtained at the baseline and after 4 and 12 weeks of treatment. The adverse events observed during administration of enteral nutrition have an negative impact on enteral formula tolerance and as a consequence patients’ quality of life. The previous studies have demonstrated that probiotics may reduce the gastrointestinal symptoms related to enteral nutrition. Thus, administration of Lactobacillus plantarum 299v may be effective in improvement of nutritional status, enteral nutrition tolerance, and quality of life of cancer patients receiving home enteral nutrition. ClinicalTrials.gov Identifier:
NCT03940768
. 相似文献
84.
Testing previously studied information enhances long-term memory, particularly when the information is successfully retrieved from memory. The authors examined the effect of unsuccessful retrieval attempts on learning. Participants in 5 experiments read an essay about vision. In the test condition, they were asked about embedded concepts before reading the passage; in the extended study condition, they were given a longer time to read the passage. To distinguish the effects of testing from attention direction, the authors emphasized the tested concepts in both conditions, using italics or bolded keywords or, in Experiment 5, by presenting the questions but not asking participants to answer them before reading the passage. Posttest performance was better in the test condition than in the extended study condition in all experiments—a pretesting effect—even though only items that were not successfully retrieved on the pretest were analyzed. The testing effect appears to be attributable, in part, to the role unsuccessful tests play in enhancing future learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Lindsey Haak Isabelle Sioen Katleen Raes John Van Camp Stefaan De Smet 《Food chemistry》2007,102(3):857-864
This study was set up to determine how pan-frying either without culinary fat or with different culinary fats (polyunsaturated fatty acids (PUFA)-enriched culinary fat, olive oil and margarine) affects the fatty acid (FA) composition of pork. The meat samples (longissimus thoracis (LT)) originated from pigs fed different dietary fat sources (animal fat, soybean oil or linseed oil) and thus had different FA compositions before frying. Pan-frying resulted in considerable increases in the meat total-FA content, although this was not always significant and highly variable, despite standardisation of the frying process. The FA composition of the pan-fried meat tended to become similar to that of the culinary fat used, and the extent of changes in the content of a particular FA was relative to the FA gradient from the culinary fat to the meat. However, this was also dependent on the culinary fat used, since frying in olive oil appeared to affect the FA composition of the meat more than did frying in the other culinary fats. Differences in FA composition of meat resulting from different animal feeding treatments remained unchanged after pan-frying without fat, they became smaller after frying in margarine and PUFA-enriched culinary fat, whereas frying in olive oil largely masked the initial FA profile differences. Long chain PUFA (LCPUFA) in the meat were not significantly lost by the frying process, but their proportion was influenced by the uptake of the culinary fat. 相似文献
86.
87.
Sonia Hammache Lindsey R. Evans Eric N. Coker James E. Miller 《Applied catalysis. B, Environmental》2008,78(3-4):315-323
The presence of sulfur in automotive exhaust is known to be detrimental to lean-NOx traps as SO2 is oxidized to SO3 that competes with NO2 for sites on the trap and is difficult to remove. In this study the effect of adding Cu to the prototypical Pt–BaO/γ-Al2O3 formulation on the system's tolerance for sulfur was investigated. It was found that in the absence of sulfur, Cu decreases the performance in terms of both NOx storage capacity and reduction of NOx to N2 during regeneration. In the presence of SO2, Cu provides a significant improvement in sulfur tolerance so that, after sulfur exposure, the storage capacity of the Cu-modified material can exceed that of the baseline material. The sulfur tolerance afforded by Cu is attributed to a moderation in the activity for SO2 oxidation resulting from the formation of a Pt–Cu bimetallic phase. The propensity for NO oxidation is also modified, but to a lesser effect. Evidence for the bimetallic phase is provided by temperature-programmed reduction (TPR) and electron microscopy. The impact of SO2 on the Cu-modified material is greater during the regenerative reduction cycle. In this case, the results suggest that sulfur blocks Pt and possibly Cu sites and that the sulfur is not removed by oxidation during the subsequent storage cycle. Hence, activity lost during the reduction cycle is not restored. In contrast, sulfur that blocks Pt sites on the baseline material during the reduction cycle is subsequently oxidized and desorbs from the Pt, restoring the activity. However, some of the resulting SO3 reacts with the BaO to form BaSO4, and there is a partial loss of storage capacity. 相似文献
88.
Set-size effects in visual search may be due to 1 or more of 3 factors: sensory processes such as lateral masking between stimuli, attentional processes limiting the perception of individual stimuli, or attentional processes affecting the decision rules for combining information from multiple stimuli. These possibilities were evaluated in tasks such as searching for a longer line among shorter lines. To evaluate sensory contributions, display set-size effects were compared with cuing conditions that held sensory phenomena constant. Similar effects for the display and cue manipulations suggested that sensory processes contributed little under the conditions of this experiment. To evaluate the contribution of decision processes, the set-size effects were modeled with signal detection theory. In these models, a decision effect alone was sufficient to predict the set-size effects without any attentional limitation due to perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Lindsey Anderson 《建筑机械》2009,(1)
在经济危机的冲击下,传统的观点认为起重机行业己最后一个受到威胁的行业,同时也是危机过后最后一个反弹的行业.比如,尽管预测在2008年底和2009年大部分时间经济黯淡,特雷克斯起重机第三季度的销售仍然比2007年同期增长了36.2%.马尼托瓦克起重机集团也发布了其第三季度的销售数字,其起重机的净销售额达9.91亿美元,相比于2007年同比增长22%. 相似文献
90.
Experimental results of far-field patterns of semiconductor laser arrays with multiple contacts are reported. It is found that, by tailoring the distribution of the currents through the array elements, narrow single-lobe patterns?which are more useful in most applications?can be obtained from arrays that usually operate in a double-lobe mode. A diffraction-limited 1.8°-wide far-field pattern was obtained from a three-element array. 相似文献