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71.
In some multiple treatment arm clinical trials there is an order of preference for the treatments based on secondary considerations like toxicity or cost. In this paper, we consider the case where two or more treatments could have equal prior preference. This formulation includes the problem of comparing several equally preferred experimental treatments to one control, or the comparison of a combination with its components. Our decision procedures will guarantee a high selection probability for the correct treatment(s) when that selection is appropriate. We establish sample size requirements for our decision procedures which can be applied to clinical trials with normal, binomial, or right censored exponential endpoints. 相似文献
72.
In a prospective open study we investigated Chlamydia pneumoniae infections in 36 consecutively admitted patients: 26 males, mean age 53.4 yr, range 36-70 yr, 10 females mean age 57.7 yr, range 47-70 yr, suffering myocardial infarction (24 acute, 2 previous) or angina pectoris (10). Antibody serum levels were measured by the immunefluorescent method and they were as follows: negative 5, low 12, medium/high 11, chronic infection 5, recent infection 3. The 3 cases considered as recent infections are described in detail. 相似文献
73.
The β and γ decay of uranium atoms from xUO3(100 - x)[3B2O3 · MO] glass systems, where M=Sr or Pb and 0 ≤ × ≤ 20 mol%, is investigated. The γ decay data are very close to each other, for the same UO3 contents, in both the systems. The composition dependence of the β decay exhibits a lower slope in the lead borate matrix than in the strontium borate matrix. The ratio between the β activity of samples with the same uranium ion concentrations in the two investigated glass systems is a function of the x values. The results are correlated with the amount of radioactive nuclides and with the structural environments of the radionuclides. The leaching treatment in water at temperatures below 100°C evidenced no aqueous dissolution of glass samples. 相似文献
74.
Koch David Despotovic Miroslav Thaler Simon Zeppelzauer Matthias 《Applied Intelligence》2021,51(11):8106-8106
Applied Intelligence - A Correction to this paper has been published: https://doi.org/10.1007/s10489-021-02433-z 相似文献
75.
Jantsch Simon Müller David Baier Christel Klein Joachim 《Formal Methods in System Design》2021,58(1-2):42-82
Formal Methods in System Design - Due to the high complexity of translating linear temporal logic (LTL) to deterministic automata, several forms of “restricted” nondeterminism have been... 相似文献
76.
C. Christopher ColumbusAuthor Vitae K. Chandrasekaran Author VitaeSishaj P. Simon Author Vitae 《Applied Soft Computing》2012,12(1):145-160
This paper proposes a nodal ant colony optimization (NACO) technique to solve profit based unit commitment problem (PBUCP). Generation companies (GENCOs) in a competitive restructured power market, schedule their generators with an objective to maximize their own profit without any regard for system social benefit. Power and reserve prices become important factors in decision process. Ant colony optimization that mimics the behavior of ants foraging activities is suitably implemented to search the UCP search space. Here a search space consisting of optimal combination of binary nodes for unit ON/OFF status is represented for the movement of the ants to maintain good exploration and exploitation search capabilities. The proposed model help GENCOs to make decisions on the quantity of power and reserve that must be put up for sale in the markets and also to schedule generators in order to receive the maximum profit. The effectiveness of the proposed technique for PBUCP is validated on 10 and 36 generating unit systems available in the literature. NACO yields an increase of profit, greater than 1.5%, in comparison with the basic ACO, Muller method and hybrid LR-GA. 相似文献
77.
Wollaston prism with large split angle 总被引:1,自引:0,他引:1
Simon MC 《Applied optics》1986,25(3):369-376
The image formation through a Wollaston prism with large split angle is studied. Formulas for the split angle, approximate calculations of aberrations, and ray tracings are used. The most important aberrations found are astigmatism and anamorphic distortion. Tilting the Wollaston with respect to the incident beam may reduce these aberrations, and if the orientation of the optical axis in the first element is varied it is possible to cancel one of the two aberrations for both images simultaneously, while the other one is substantially reduced. With an adequate adjustment of all the construction parameters the images become sharp enough to allow the use of large split angles (approximately 15 degrees). 相似文献
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Interleukin 6 (IL-6) is a prominent proinflammatory cytokine. Neuroinflammation in general, and IL-6 signaling in particular, appear to play a major role in the pathobiology and pathophysiology of aneurysm formation and aneurysmal subarachnoid hemorrhage (SAH). Most importantly, elevated IL-6 CSF (rather than serum) levels appear to correlate with delayed cerebral ischemia (DCI, “vasospasm”) and secondary (“vasospastic”) infarctions. IL-6 CSF levels may also reflect other forms of injury to the brain following SAH, i.e., early brain damage and septic complications of SAH and aneurysm treatment. This would explain why many researchers have found an association between IL-6 levels and patient outcomes. These findings clearly suggest CSF IL-6 as a candidate biomarker in SAH patients. However, at this point, discrepant findings in variable study settings, as well as timing and other issues, e.g., defining proper clinical endpoints (i.e., secondary clinical deterioration vs. angiographic vasospasm vs. secondary vasospastic infarct) do not allow for its routine use. It is also tempting to speculate about potential therapeutic measures targeting elevated IL-6 CSF levels and neuroinflammation in SAH patients. Corticosteroids and anti-platelet drugs are indeed used in many SAH cases (not necessarily with the intention to interfere with detrimental inflammatory signaling), however, no convincing benefit has been demonstrated yet. The lack of a robust clinical perspective against the background of a relatively large body of data linking IL-6 and neuroinflammation with the pathophysiology of SAH is somewhat disappointing. One underlying reason might be that most relevant studies only report correlative data. The specific molecular pathways behind elevated IL-6 levels in SAH patients and their various interactions still remain to be delineated. We are optimistic that future research in this field will result in a better understanding of the role of neuroinflammation in the pathophysiology of SAH, which in turn, will translate into the identification of suitable biomarkers and even potential therapeutic targets. 相似文献