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1.
One of the most complex issues in the cloud computing environment is the problem of resource allocation so that, on one hand, the cloud provider expects the most profitability and, on the other hand, users also expect to have the best resources at their disposal considering the budget constraints and time. In most previous work conducted, heuristic and evolutionary approaches have been used to solve this problem. Nevertheless, since the nature of this environment is based on economic methods, using such methods can decrease response time and reducing the complexity of the problem. In this paper, an auction-based method is proposed which determines the auction winner by applying game theory mechanism and holding a repetitive game with incomplete information in a non-cooperative environment. In this method, users calculate suitable price bid with their objective function during several round and repetitions and send it to the auctioneer; and the auctioneer chooses the winning player based the suggested utility function. In the proposed method, the end point of the game is the Nash equilibrium point where players are no longer inclined to alter their bid for that resource and the final bid also satisfies the auctioneer’s utility function. To prove the response space convexity, the Lagrange method is used and the proposed model is simulated in the cloudsim and the results are compared with previous work. At the end, it is concluded that this method converges to a response in a shorter time, provides the lowest service level agreement violations and the most utility to the provider.  相似文献   
2.

Background  

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD.  相似文献   
3.

Background

Neuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.

Methods

We translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.

Results

Using a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.

Conclusions

The NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain.  相似文献   
4.
A combined centrifugal, biochemical, and electron microscopic study of the cytoplasmic particulates present in 0.88 M sucrose homogenates of rat liver has been carried out. Size distribution analyses of particles containing pentose nucleic acid (PNA) and exhibiting several types of enzymatic activity revealed three major size groups within the range of particle radius between 10 and 500 mmicro. A different array of biochemical properties was associated with each size group. The largest particles, with an average radius (assuming spherical shape) in the region of 220 to 260 mmicro, contained all of the succinic dehydrogenase activity of the cytoplasmic extract, 29 per cent of the diphosphopyridine nucleotide (DPN)-cytochrome c reductase activity, and minor amounts of PNA and acid phosphatase activity. Cytologically, this group of particles was identified with the mitochondria. All of the uricase activity, 58 per cent of the acid phosphatase activity, and 26 per cent of the PNA was apparently associated with a second size group of particles (average radius 120 mmicro) which were tentatively identified by electron microscopy with vesicular structures derived from the ergastoplasm of the intact cell. The third particle group demonstrated by centrifugation exhibited a major size distribution peak at 25 mmicro and a second smaller peak at 55 mmicro. Over 50 per cent of the total cytoplasmic PNA and DPN-cytochrome c reductase activity was associated with particles in this size group. Electron microscopy revealed a morphologically heterogeneous population of particles within this size range.  相似文献   
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Background  

The zebrafish, Danio rerio, is used as a model organism to study vertebrate genetics and development. An effective enhancer trap (ET) in zebrafish using the Tol2 transposon has been demonstrated. This approach could be used to study embryogenesis of a vertebrate species in real time and with high resolution.  相似文献   
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SEPALLATA3: the 'glue' for MADS box transcription factor complex formation   总被引:1,自引:0,他引:1  

Background  

Plant MADS box proteins play important roles in a plethora of developmental processes. In order to regulate specific sets of target genes, MADS box proteins dimerize and are thought to assemble into multimeric complexes. In this study a large-scale yeast three-hybrid screen is utilized to provide insight into the higher-order complex formation capacity of the Arabidopsis MADS box family. SEPALLATA3 (SEP3) has been shown to mediate complex formation and, therefore, special attention is paid to this factor in this study.  相似文献   
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