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101.
L. V. Hedges and I. Olkin (1985) presented a statistic to test for homogeneity among correlated effect sizes and L. J. Gleser and I. Olkin (1994) presented a large-sample approximation to the covariance matrix of the correlated effect sizes. This article presents a more exact expression for this covariance matrix, assuming normally distributed data but not large samples, for the situation where effect sizes are correlated because a single control group was compared with more than one treatment group. After the correlation between effect sizes has been estimated, the standard Q statistic for correlated effect sizes can be used to test for homogeneity. This method is illustrated using results from schizophrenia research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Beardsley Patrick M.; Aceto Mario D.; Cook Charles D.; Bowman Edward R.; Newman Jennifer L.; Harris Louis S. 《Canadian Metallurgical Quarterly》2004,12(3):163
Despite oxycodone's (4,5-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one) history of clinical use and the attention it has received as a drug of abuse, few reports have documented its pharmacology's relevance to its abuse or its mechanism of action. The purposes of the present study were to further characterize the analgesic effects of oxycodone, its mechanism of action, and its effects in terms of its relevance to its abuse liability. The results indicate that oxycodone had potent antinociceptive effects in the mouse paraphenylquinone writhing, hot-plate, and tail-flick assays, in which it appeared to be acting as a μ-opioid receptor agonist. It generalized to the heroin discriminative stimulus and served as a positive reinforcer in rats and completely suppressed withdrawal signs in morphinedependent rhesus monkeys. These results suggest that the analgesic and abuse liability effects of oxycodone are likely mediated through μ-opioid receptors and provide the first laboratory report of its discriminative stimulus, reinforcing, and morphine cross-dependency effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
E. J. O'Brien, M. L. Rizzella, J. E. Albrecht, and J. G. Halleran (1998) demonstrated that, consistent with the memory-based text processing view, outdated or incorrect information can be reactivated through a passive resonance process. Once reactivated, this outdated information can still influence comprehension. R. A. Zwaan and C. J. Madden (2004) suggested that the O'Brien et al. findings resulted from problems with the materials used. The present authors show that the possible "problems" identified by Zwaan and Madden do not adequately explain the findings of O'Brien et al. and that Zwaan and Madden's Experiment 3 lacks sufficient control or power to support their alternative interpretation of O'Brien et al. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Errors in the refractive and absorptive indices derived from reflectance measurements on relatively low-absorbing organic substances in two media are discussed, with particular reference to coal macerals and cokes. Variation of errors in refractive and absorptive indices at different levels of reflectance, and the effect of different combinations of sign and magnitude of reflectance error on the two parameters, are presented in both tabulated form and as diagrams. The errors in the refractive and absorptive indices vary in relation to reflectance level, the reflectance difference between standard and unknown, the difference between the refractive indices of the unknown and the immersion oil and the wavelength of reflectance measurement within the visible spectrum. Despite the variation, it is possible to obtain useful values for the parameters within the low-absorbing range. If the absorption is negligible, it may not be possible to obtain realistic values for absorptive index, but even where this is the case, satisfactory values for refractive index can still be obtained. Suggestions are made on how to minimize reflectance errors and to increase the accuracy of dispersion curves for derived refractive and absorptive indices within the visible spectrum. 相似文献
105.
106.
A custom, low-cost force measurement system for manufacturing is presented that exploits robotic link deflection for measurement purposes instead of utilizing a commercially purchased load cell. Force measurement can be an important aspect to many manufacturing processes, as it can allow for force feedback control or other process-planning related operations, such as tool-workpiece autozero or through-the-tool joint tracking. This system is demonstrated on a machine that is used for Friction Stir Welding research, and a Finite Element Analysis is also conducted on the robotic link that is used for axial force measurement purposes. This system may be particularly attractive to small businesses or low-volume manufacturers whose smaller operating budgets may normally prohibit them from implementing force measurement systems. 相似文献
107.
The potential for community-led local sustainability initiatives to play a key role in a transition towards a low-carbon economy has been acknowledged by both policymakers and researchers. To date, such initiatives have predominantly been established through the efforts of volunteers, resulting in a scattered uptake across towns, cities and other communities in the UK and further afield. In a context where local and national Government are increasingly seeking to deliver local action on climate change in partnership with community organisations, is it possible or desirable for Government and other publicly funded bodies to successfully set up these grassroots initiatives “from the outside” where none exist already? This paper describes a project which explored this question through the provision of a 2-year programme of support for local action on climate change in a sub-region of the UK. Community development strategies were employed with a view to establishing new grassroots climate change initiatives in a range of different communities. The results indicate some potential for the strategy to meet with success, with several new groups and small-scale projects being established as a result. However, the short lifespan of many of the organisations set up and the relatively low impact on carbon emission reduction of their activities raises questions about the effectiveness of grassroots initiatives and how support of their activities can be delivered most effectively to maximise impact and improve cost effectiveness. 相似文献
108.
Ignition of the external combustible elements of a building is one of the key factors leading to house loss in bushfires. Timber elements contain moisture that migrates into and out from the timber surface, depending on the surrounding ambient conditions. In extreme hot and dry conditions, such as those associated with severe bushfire weather, the moisture contents (MCs) in building timbers can drop well below the normal levels. In this paper, we not only qualify a methodology to assess the likely MCs of timbers under typical bushfire conditions, but also quantify the low levels of moisture that can be expected for the climatic conditions experienced in Melbourne—one of Australia's bushfire‐prone regions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
109.
110.
Mehrdad Hamrahian Karen T. Pitman Éva Csongrádi Justin H. Bain Béla Kanyicska Tibor Fülöp 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(4):571-576
We are reporting on a series of two patients with end‐stage renal disease on hemodialysis, presented for surgical parathyroidectomy secondary refractory hyperparathyroidism. Both patients had failed maximized medical managements, including higher‐than‐usual doses of the calcimimetic cinacalcet (270 and 180 mg/day, respectively). On physical exam, both patients had marked symmetrical craniofacial hypertrophy with coarse distortion of facial features, similar in appearance to past reports of Sagliker syndrome. On X‐ray and computed tomographic exam, they had peculiar areas of bone absorption on the skull, imitating the radiologic appearance of multiple myeloma. Bone biopsy of the maxilla, however, did not show the expected brown tumor, but rather described only fibrosis and reactive bone formations. This phenotype developed while being on cinacalcet, progressed despite escalation of therapy, and improved only after parathyroidectomy. Both patients developed massive “hungry bone syndrome” after parathyroidectomy necessitating prolonged IV calcium infusion. This pattern of severe facial distortion likely represented an adverse consequence of severe tertiary hyperparathyroidism, along with supraphysiologic dose of cinacalcet administration and 25‐hydroxy vitamin D deficiency in sensitive individuals. The genetic base of this observation remained unexplained. 相似文献