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161.
Ideographic representations (schematic drawings) are useful for analyzing and communicating complex ideas. They constitute simplified versions of the way multiple and diverse elements, concepts, and variables interact according to each author's conceptions, knowledge, and experience of planned change and change phenomena. Such representations depict a sense of order under a particular model configuration or system notion, involving contexts where action takes place and events occur. This paper is based on the commonality analysis of 46 models related to technology transfer. Within the framework of previously published research, complementary findings are presented here. The discussion is focused on the characteristics of the models' contexts, appealing to some technology transfer aspects widely omitted or neglected. It is suggested that the understanding of intervention contextual domains is important to formulate and implement better technology transfer models. 相似文献
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Valéry Ridde ? 《Development in Practice》2005,15(1):4-15
The reconstruction of the health system in Afghanistan is in its early stages, and donors have proposed Performance-based Partnership Agreements (PPAs) through which to subcontract the delivery of health services to private organisations, both for-profit and not-for-profit. Beyond ideological debates, this article sets out to explain the model underlying the PPA initiative and sheds light on empirical data concerning the assumed benefits of such an approach. The article studies privatisation and the contracting-out of health services, though there is as yet no information that can demonstrate the superiority of private over public service provision. Similarly, the merits of subcontracting have not been fully proven and such arrangements raise several ethical issues. Where PPAs are to be attempted, it is important to remain cautious and to ensure that operations are organised in such a way as to permit proper comparison. The paper concludes with recommendations to organisations involved in or considering the advantages of PPAs. 相似文献
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Jackowski C Bolliger S Aghayev E Christe A Kilchoer T Aebi B Périnat T Dirnhofer R Thali MJ 《Journal of forensic sciences》2006,51(5):1134-1137
Postmortem investigation is increasingly supported by computed tomography (CT) and magnetic resonance imaging, in which postmortem minimal invasive angiography has become important. The newly introduced approach using an aqueous contrast agent solution provided excellent vessel visualization but was suspected to possibly cause tissue edema artifacts in histological investigations. The aim of this study was to investigate on a porcine heart model whether it is possible to influence the contrast agent distribution within the soft tissue by changing its viscosity by dissolving the contrast agent in polyethylene glycol (PEG) as a matrix medium. High-resolution CT scans after injection showed that viscosities above c. 15 mPa s (65% PEG) prevented a contrast agent distribution within the capillary bed of the left ventricular myocardium. Thereby, the precondition of edema artifacts could be reduced. Its minimal invasive application on human corpses needs to be further adapted as the flow resistance is expected to differ between different tissues. 相似文献
169.
The Suicide Risk Assessment Scale (SRAS; nine items) is useful in correctional settings but needed further validation. First, 44 inmates originally screened as suicidal with the SRAS were evaluated by institutional psychologists according to five criteria: suicidal urgency, risk, appropriateness of referral, need for short- or long-term watch. On the whole, the SRAS was judged to be as effective as a more elaborate test. Second, 242 suicidal and non-suicidal inmates were tested with the SRAS. Their results correlated better with suicidal risk (.71) than with urgency (.50). Receiver operating characteristic (ROC) analysis even showed that the SRAS performed better than a more elaborate test in predicting risk. 相似文献
170.
The occurrence of two null alleles for the same individual was suspected because of the discrepancy at two loci (vWA and THO1) between genotypes characterized by the mean of two different commercial kits. Reanalysis of the samples indicated there was no null allele, and that this abnormality was indeed related to an automatic laser power shutdown. The laser power supply was set to a value (6.4V) too close to the automatic shutdown threshold (6.0V). The alleles were undetected because of the absence of emission at the time of migration of the two alleles through the detection device. However, since no alarm is triggered in such an event, the users should monitor their laser power supply values. 相似文献