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91.
In the last years, trust management has become a fundamental basis for facilitating the cooperation between different users in peer-to-peer (P2P) multimedia applications within autonomic networks. In these networks and applications, trust management should fulfill certain requirements (i.e. decentralisation, dynamism, simplicity, interoperability, etc.) for being functional. In this paper, we propose an evolutionary model of trust management that captures dynamic entities’ behaviour over time. Likewise, we explain protection mechanisms against several attacks, which are based on the cooperative behaviour of the entities, trust relationship properties, and trust rules. Finally, we successfully validate our model from several scenarios and compare it with other proposals in this field.  相似文献   
92.
Organizational change can become a source of resistance and stress if it is implemented without attention to the needs of organizational members. The participants in the present study (604 government employees) work in a climate of ongoing change and, thus, are at particular risk for experiencing high levels of stress and other deleterious consequences. This study examines and finds support for the central role played by procedural and distributive fairness in mediating the effects of change justification and voice on the extent to which employees experience stress, which, in turn, predicts their levels of work effort, intention to leave, and a host of physiological and affective symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
The gadobenate ion is an intravascular paramagnetic contrast agent for magnetic resonance imaging. An HPLC method for assaying gadobenate ion in plasma, urine, faeces, bile and tissue samples is described. The analysis is based on the reversed-phase chromatographic separation of gadobenate ion from the endogenous components of biological matrices and detection by UV absorption at 210 nm. The selectivity of the method was satisfactory. The mean absolute recovery was greater than 95%. The precision and accuracy of the analytical methods were in the range 0.1-6.5% and -12 to +9.3%, respectively. The detection limits in plasma (0.1 ml), urine (0.05 ml), dried faeces (200 mg suspended in 4 ml water), bile (0.5 ml), and dried liver tissue (100 mg suspended in 1 ml water) were, respectively, 0.24, 0.47, 2.6, 0.63 and 2.8 nmol ml(-1) (corresponding to 0.16, 0.31, 1.7, 0.42 and 1.9 microg ml(-1)).  相似文献   
94.
Advances in clinical genetics and biotechnology increase the ability to identify individual genetic makeup through genetic services and testing. As a result, genes have become the focus of an increasing number of health messages associated with medical interaction and public communication. This research explored public perceptions ( N = 858) of the role of genes in health using problematic integration (PI) theory as a framework. A Genetic Relativism Instrument (GRI) associated with macroframeworks about illness causation was developed and used to cluster individuals into 4 groups associated with communicating about genes and health. Uncertainty about the role of personal behaviors, social environments, and religious faith on genes' impact for human health varied significantly among the four groups. In this age of increased use of genetic technologies, communication regarding human genetics in counseling and health promotion may contribute to better informed decision making if tailored to these varied belief systems.  相似文献   
95.
Ann Elizabeth Kelley was truly a Renaissance woman. Internationally recognized as a conceptual leader in the psychology of brain and behavior, she also excelled as an educator, mentor, athlete, humanist, philanthropist, activist, colleague, friend, and mother. The impact of her contributions to psychology has been particularly significant to our understanding of the neuroanatomical and neurochemical substrates that underlie reward and motivation. Her discoveries shaped current views on numerous pathologies of the human brain including obesity, drug addiction, and affective disorders. On August 5, 2007, at the height of her rich professional and personal life, Ann succumbed to a 16-month battle with metastatic colon cancer in her home in Madison, Wisconsin. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Characterizing instability phenomena in arc welding may be a complex task, since they depend on a number of interrelated factors. Such phenomena may manifest themselves in various ways, acting on the characteristics of the arc, the metal transfer, the amount of splatter and fumes formed, the arc format, the geometry of the bead and other aspects of welding. The literature on the subject reports diverse forms of instability associated with arc welding with solid wire and gas shielding (GMAW). This work aimed to define the instability phenomena associated with the GMAW process in welding with gases with a low oxidation potential. To do so, the welding current and voltages were monitored and metal transfer was filmed at high speed. The welding tests were carried out on plates of common carbon steel with a source operating at a constant current and an electrode with positive polarity. By synchronizing the filming with the welding current and voltage signals, the results showed that, during the periods of highest voltage, the transfer tended to be globular repulsive, as opposed to spray transfer during the lowest voltage periods. The synchronization of the electrical signals with the optical sensor indicates that, during periods of unstable operation, the arc is more luminous. It also showed that more fumes were generated during these periods.  相似文献   
97.
On the National Ignition Facility (NIF), hot electrons generated in laser heated Hohlraums are inferred from the >20?keV bremsstrahlung emission measured with the time integrated FFLEX broadband spectrometer. New high energy (>200?keV) time resolved channels were added to infer the generated >170?keV hot electrons that can cause ignition capsule preheat. First hot electron measurements in near ignition scaled Hohlraums heated by 96-192 NIF laser beams are presented.  相似文献   
98.
The static x-ray imager at the National Ignition Facility is a pinhole camera using a CCD detector to obtain images of Hohlraum wall x-ray drive illumination patterns seen through the laser entrance hole (LEH). Carefully chosen filters, combined with the CCD response, allow recording images in the x-ray range of 3-5 keV with 60?μm spatial resolution. The routines used to obtain the apparent size of the backlit LEH and the location and intensity of beam spots are discussed and compared to predictions. A new soft x-ray channel centered at 870 eV (near the x-ray peak of a 300 eV temperature ignition Hohlraum) is discussed.  相似文献   
99.
Epilepsy is a pathologic condition with high prevalence and devastating consequences for the patient and its entourage. Means for accurate diagnosis of type, patient monitoring for predicting seizures and follow up, and efficacious treatment are desperately needed. To improve this adverse outcome, miRNAs and the chaperone system (CS) are promising targets to understand pathogenic mechanisms and for developing theranostics applications. miRNAs implicated in conditions known or suspected to favor seizures such as neuroinflammation, to promote epileptic tolerance and neuronal survival, to regulate seizures, and others showing variations in expression levels related to seizures are promising candidates as useful biomarkers for diagnosis and patient monitoring, and as targets for developing novel therapies. Components of the CS are also promising as biomarkers and as therapeutic targets, since they participate in epileptogenic pathways and in cytoprotective mechanisms in various epileptogenic brain areas, even if what they do and how is not yet clear. The data in this review should help in the identification of molecular targets among the discussed miRNAs and CS components for research aiming at understanding epileptogenic mechanisms and, subsequently, develop means for predicting/preventing seizures and treating the disease.  相似文献   
100.
The self-assembled domain patterns of modulated systems are the result of competing short-range attractive and long-range repulsive interactions found in diverse physical and chemical systems. From an application point of view, there is considerable interest in these domain patterns, as they form templates suitable for the fabrication of nanostructures. In this work we have generated a variety of new and exotic patterns, which represent either metastable or glassy states. These patterns arise as a compromise between the required equilibrium modulation period and the strain resulting from topologically constrained trajectories in phase space that effectively preclude the equilibrium configuration.  相似文献   
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