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排序方式: 共有676条查询结果,搜索用时 15 毫秒
1.
The article proposes a theoretical framework in which moral reasoning about mediated crime and punishment is defined and combined with existing, affect-driven entertainment theory to yield an integrated theory of enjoyment. The authors analyze how crime dramas serve as statements about justice and then address how moral deliberation about the propriety of those statements impacts enjoyment. The authors report research findings to support the analysis of cognitive processing during crime dramas distinct from affective processing. The article also suggests future means by which the integrated theory of enjoyment can be examined. 相似文献
2.
Jennings Jerry L.; Williams Charles; Thompson-Owens Margie 《Canadian Metallurgical Quarterly》1994,31(4):700
Presents a model for conceptualizing 4 basic types of suicidality among substance abusers (avoidance of painful consequences, the depressive experience of "crashing," the threat of personal loss, and environmental strain) and offers practical tips for treating the problem. Four general forms of intervention are discussed: pacing the crisis encounter; desensitizing the patient's sense of desperation; talking frankly about the suicidality; and attending to one's own needs as a counselor. These crisis-intervention tips are intended to aid counselors in handling suicidality as it is manifested in substance-abusing populations. Tips and guidelines for suicidal risk assessment with drug and alcohol abusers are given. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
On agent-mediated electronic commerce 总被引:4,自引:0,他引:4
Minghua He Jennings N.R. Ho-Fung Leung 《Knowledge and Data Engineering, IEEE Transactions on》2003,15(4):985-1003
This paper surveys and analyzes the state of the art of agent-mediated electronic commerce (e-commerce), concentrating particularly on the business-to-consumer (B2C) and business-to-business (B2B) aspects. From the consumer buying behavior perspective, agents are being used in the following activities: need identification, product brokering, buyer coalition formation, merchant brokering, and negotiation. The roles of agents in B2B e-commerce are discussed through the business-to-business transaction model that identifies agents as being employed in partnership formation, brokering, and negotiation. Having identified the roles for agents in B2C and B2B e-commerce, some of the key underpinning technologies of this vision are highlighted. Finally, we conclude by discussing the future directions and potential impediments to the wide-scale adoption of agent-mediated e-commerce. 相似文献
4.
GW Lambert DM Kaye HS Cox M Vaz AG Turner GL Jennings MD Esler 《Canadian Metallurgical Quarterly》1995,57(3):255-267
Veno-arterial plasma concentration differences and regional organ plasma flows were used to quantify the relative amounts of 5-hydroxyindoleacetic acid (5-HIAA) contributed by various sites into the peripheral circulation. Positive venoarterial concentration gradients were found in the hepatosplanchnic, forearm, cardiac and jugular vessels in the healthy subjects. The renal circulation was determined to be the principal site of 5-HIAA clearance, extracting 18 +/- 2 nmol/min. The gut was the greatest contributor to the total 5-HIAA plasma pool with the relative contributions of the various organs being as follows: hepatosplanchnic organs 58%, skeletal muscle 26%, brain 6% and the heart 3%. The source of 5-HIAA stemming from these regional beds remains unknown, it may derive from serotonin taken up by and deaminated in ubiquitous endothelial cells, enterochromaffin cells of the gut, peripheral serotonergic nerves, serotonin turnover in platelets or perhaps the metabolism of serotonin taken up by sympathetic nerves. To test the latter hypothesis we examined 23 patients with chronic congestive heart failure and 9 patients with pure autonomic failure to investigate the possible effects of sympathetic nervous system overactivity and underactivity on peripheral 5-HIAA production and plasma 5-HIAA concentration. The resting arterial plasma 5-HIAA concentration in the heart failure patients was increased three-fold. This elevated plasma 5-HIAA concentration was attributable to an increased rate of whole body 5-HIAA production. The arterial 5-HIAA plasma concentration in the autonomic failure patients was paradoxically elevated, being 70% greater than that of the healthy subjects. The increased 5-HIAA plasma concentration in these patients was accounted for by a reduction in 5-HIAA plasma clearance. In all subjects studied there was a weak relationship only between total body norepinephrine spillover to plasma and the arterial 5-HIAA plasma concentration. We found that in healthy subjects the overflow of 5-HIAA into the hepatic vein was significantly related to the underlying degree of sympathetic activity. It can be concluded that 5-HIAA is produced at a number of sites throughout the body with the arterial plasma concentration being dependent on both the level of production and plasma clearance. By far the majority of 5-HIAA in plasma is derived from the gut with only minimal contribution from the brain. 相似文献
5.
Excessive brain iron has been found in several neurodegenerative diseases. However, little information is available about mechanism of iron uptake by different types of brain cells including neurons. In this study, transferrin-bound iron (Tf-Fe) accumulation in the cultured cerebellar granule cell was investigated in vitro. After 5 days of culture, the cells were incubated with 1 microM of double-labelled transferrin (1251-Tf-59Fe) at 37 degrees C for 60 min. The cellular Tf-Fe and transferrin (Tf) uptake was analysed. The result showed (1) Tf uptake by the cells increased rapidly at the first 5 min, reaching its maximum after about 20 min of incubation; (2) Tf-Fe uptake kept increasing in a linear manner during the whole period of incubation; (3) the addition of either NH4Cl or CH3NH2, the blockers of Tf-Fe uptake via inhibiting iron release from Tf within endosomes, decreased the cellular Tf-Fe uptake but had no significant effect on Tf uptake; (4) trypsin and unlabelled Tf-Fe inhibited the uptake rate of Tf-Fe as well as Tf. The results suggested that Tf-Fe transport across the membrane of this type of neuron, much like other mammalian cells, was mediated by Tf-TfR endocytosis. Dysfunction of Tf or TfR would possibly lead to iron irregulation in the brain and consequently cause damage to neuronal functions. 相似文献
6.
Long Tran-Thanh Alex Rogers Nicholas R. Jennings 《Autonomous Agents and Multi-Agent Systems》2012,25(2):352-394
This paper reports on the development of a multi-agent approach to long-term information collection in networks of energy harvesting wireless sensors. In particular, we focus on developing energy management and data routing policies that adapt their behaviour according to the energy that is harvested, in order to maximise the amount of information collected given the available energy budget. In so doing, we introduce a new energy management technique, based on multi-armed bandit learning, that allows each agent to adaptively allocate its energy budget across the tasks of data sampling, receiving and transmitting. By using this approach, each agent can learn the optimal energy budget settings that give it efficient information collection in the long run. Then, we propose two novel decentralised multi-hop algorithms for data routing. The first proveably maximises the information throughput in the network, but can sometimes involve high communication cost. The second algorithm provides near-optimal performance, but with reduced computational and communication costs. Finally, we demonstrate that, by using our approaches for energy management and routing, we can achieve a 120% improvement in long-term information collection against state-of-the-art benchmarks. 相似文献
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9.
Jay R Hoffman Jie Kang Nicholas A Ratamess Peter F Jennings Gerald Mangine Avery D Faigenbaum 《Journal of the International Society of Sports Nutrition》2006,3(1):35-7
Background
The purpose of this study was to examine the effect of nutritionally enriched JavaFit™ (JF) coffee (450 mg of caffeine, 1200 mg of garcinia cambogia, 360 mg of citrus aurantium extract, and 225 mcg of chromium polynicotinate) on resting oxygen uptake (VO2), respiratory exchange ratio (RER), heart rate (HR), and blood pressure (BP) in healthy and physically active individuals. 相似文献10.
Caleb Krouse Aaron A. Jennings Dario Gasparini 《Environmental Modelling & Software》2009,24(4):557-568
Consumer batteries littered on urban pavements release metals of environmental significance (Ag, Cd, Cr, Cu, Hg, Li, Mn, Ni, Pd, Ti, Zn) to stormwater runoff. Predicting the mass loading of any one metal is difficult because of the random composition of battery litter. However, when littering is modeled as a conditional filtered Poisson process, bounds may be estimated for the mean and variance of site mass loading for any metal if the site litter rate and battery product contributions are known. Site-specific data on the battery brand distribution in litter can improve load estimates, but statistics computed from 5500 littered batteries collected in the Cleveland area may be used to approximate the brand distribution. Zinc load calculations based on battery litter size, type and brand discretizations are implemented in a model titled BLML and illustrated for a case-study location. Results indicate that, at some urban sites, zinc released from battery litter can be the largest source of zinc in urban pavement runoff. 相似文献