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1.
The role of implicit theories in behavioral judgments continues to be a source of debate. In a study exploring the factorial validity of student ratings of instruction, Cadwell and Jenkins (1985) suggested that students' implicit theories of instructor behavior may account for the robust factor structure underlying student ratings. They argued that students rely on the semantic similarity of the rating items, inflating the observed relations among the items. Marsh and Groves cite methodological and conceptual difficulties with the Cadwell and Jenkins study, but most of these difficulties may arise from Marsh and Groves's misconceptions about the role of implicit theories and semantic similarities and, more generally, the cognitive processes underlying judgment tasks. I review these issues and address various points of Marsh and Groves's critique. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
We report a patient with a metastatic parathyroid carcinoma and medullary carcinoma of the thyroid. This patient represents a variation of the multiple endocrine neoplasia syndrome (MEN) type 2A. There was no evidence of a phaeochromocytoma. The case illustrates the difficulties that may be encountered in localising the source of PTH secretion; the patient underwent four unsuccessful exploratory operations of the neck and mediastinum before further investigations revealed a single metastatic deposit of parathyroid carcinoma involving the first thoracic vertebra. PCR amplification and sequencing of the RET oncogene from the metastatic parathyroid carcinoma and genomic DNA revealed a heterozygous mutation (Cys634Tyr) in exon 11, as has previously been described to occur in MEN 2A. In addition, loss of tumour heterozygosity was demonstrated at loci from chromosomes 1, 2, 3p, 13q and 16p. This represents the first report of a parathyroid carcinoma in a MEN2A patient, in which the multiple allelic deletions are consistent with the generalised losses observed in aggressive tumours.  相似文献   
3.
The measurement of the accumulated phase error of phase-locked loops (PLLs) in microprocessor systems is discussed. A system which creates controlled power supply noise and measures the PLL response is described. Examples of the use of this technique are shown for a PLL used in a 400 MHz microprocessor  相似文献   
4.
The mass childhood immunization programme has traditionally been viewed as a safe and effective preventative measure by health promoters, primary health care professionals and governments. This consensus has meant that immunization has rarely been viewed as ethically problematic. A number of recent changes in the context of the delivery of health care, particularly the emphasis on consumerism and the effect of the marketization of services, makes timely an examination of ethical, social and political issues. This article examines four main grounds for problematizing the mass childhood immunization programme. These are: clinical research evidence about the safety and efficacy of vaccines; the masking of wider social and political determinants of ill health; the contradictory strictures about collective and individual rights in relation to immunization; and the uniqueness of childhood immunization as a physical intrusion into a healthy body. The implications of these ethical issues are discussed in relation to informed consent and the need for a 'greenfield' review that includes the views of dissenting parents, lawyers and moral philosophers, as well as health professionals.  相似文献   
5.
Deterministic and stochastic Petri net models of protection schemes   总被引:1,自引:0,他引:1  
The authors establish the relevance of Petri net modeling to protection studies. They illustrate how the different Petri net models capture the information that is of importance to both qualitative and quantitative evaluation of protection schemes. The marked Petri nets allow one to evaluate the qualitative performance measures of conservativeness, safeness, and properness. Time Petri nets are able to represent the timing parameters of protection schemes, and serve as a tool for the establishment of relationships between these parameters, in order that the coordination between primary and backup protection is ensured. An alternative means of representing timing information is the timed Petri net, which is useful in the computation of the cycle times of the operational cycles of protection schemes. Stochastic Petri nets adequately represent the stochastic nature of protection. Their advantage over simulation techniques as a means of computing the mean sojourn time and the steady-state probability of occupancy of each state of the protection scheme is demonstrated  相似文献   
6.
近几年国内外许多大品牌纷纷更换自己的标志,从柯达、富士到英特尔,从中国联通到腾讯网,从联想到创维,再到华为等,那么导致品牌换标的原因是什么?标志的再设计在其中起到一个怎样的作用?  相似文献   
7.
Sustaining Rural Landscapes: the role of integrated tourism   总被引:2,自引:0,他引:2  
The aim of a European Union-funded research project entitled 'Supporting and Promoting Integrated Tourism in Europe's Lagging Rural Regions' (SPRITE) is to analyse and develop the potential for better-integrated tourism in the rural landscapes of Europe. Integrated tourism can be defined as that which is explicitly linked to the localities in which it takes place and, in practical terms, has clear connections with local resources, activities, products, production and service industries, and a participatory local community. Enhancing the sustainable economic potential of rural landscapes requires partnerships among rural people and the sustainable yet productive use of rural resources. A 'culture economy' approach to integrated tourism is proposed, which emphasizes the importance of local identity, the strategic commodification of resources and of place, and the importance of extra-local forces in enabling local activities. It is suggested that this approach may represent a shift beyond more traditional approaches to rural development.  相似文献   
8.
Our previous receiver operating characteristic (ROC) study indicated that the detection accuracy of microcalcifications by radiologists is significantly reduced if mammograms are digitized at 0.1 mm x 0.1 mm. Our recent study also showed that detection accuracy by computer decreases as the pixel size increases from 0.035 mm x 0.035 mm. It is evident that very large matrix sizes have to be used for digitizing mammograms in order to preserve the information in the image. Efficient compression techniques will be needed to facilitate communication and archiving of digital mammograms. In this study, we evaluated two compression techniques: full frame discrete cosine transform (DCT) with entropy coding and Laplacian pyramid hierarchical coding (LPHC). The dependence of their efficiency on the compression parameters was investigated. The techniques were compared in terms of the trade-off between the bit rate and the detection accuracy of subtle microcalcifications by an automated detection algorithm. The mean-square errors in the reconstructed images were determined and the visual quality of the error images was examined. It was found that with the LPHC method, the highest compression ratio achieved without a significant degradation in the detectability was 3.6:1. The full frame DCT method with entropy coding provided a higher compression efficiency of 9.6:1 at comparable detection accuracy. The mean-square errors did not correlate with the detection accuracy of the microcalcifications. This study demonstrated the importance of determining the quality of the decompressed images by the specific requirements of the task for which the decompressed images are to be used. Further investigation is needed for selection of optimal compression technique for digital mammograms.  相似文献   
9.
An experiment to determine the effect of gate electrode resistivity on circuit speed gave unexpected results: circuits with the lowest sheet resistance had the poorest circuit speed. Explanation of this behaviour required development of a new high-frequency method of measuring the impedance of the gate electrode. This method revealed that the circuits with a composite gate electrode had been formed with a partial discontinuity. The measurement technique is described, and the evidence of the discontinuity is shown. The effect of the discontinuity on device and circuit speed is demonstrated  相似文献   
10.
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