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101.
This article concludes a two part theoretical study of the problem of hacking, considering strategies of computer crime control, the changing face of social order and policy implications that these generate.  相似文献   
102.
PURPOSE: The Commission on Cancer of the American College of Surgeons conducts Patient Care Evaluation studies to describe practice patterns and trends in disease management. This report surveys changing strategies in the initial treatment of patients with invasive cancer of the uterine cervix. METHODS AND MATERIALS: Using a standard data collection form designed by a multidisciplinary committee of specialists, cancer registrars at 703 hospitals submitted anonymous data on 11,721 total cervical cancer patients diagnosed in 1984 and 1990. RESULTS: Between the two study years, the use of radiation as all, or a component, of the initial course of therapy declined from 70 to 60.3%, coincident with a 32.3% increase in the use of hysterectomy alone and a 33.7% reduction in the use of radiation alone. The percentage of all patients receiving combined hysterectomy and radiation (preoperative or postoperative) remained virtually unchanged--10.2% in 1984, and 9.3% in 1990. However, women who were treated by hysterectomy in 1990 were less likely to receive radiation as part of their treatment than patients treated by hysterectomy in 1984. Among patients treated by radiation without hysterectomy, the use of intracavitary brachytherapy techniques substantially exceeded interstitial brachytherapy techniques in both study years. Among patients treated by local radiation without hysterectomy, the frequency of adjunctive chemotherapy use increased from 6.9% in 1984 to 24.8% in 1990, with chemotherapy and radiation increasingly administered concurrently rather than sequentially. Although differences based on age, histology, race/ethnicity, and insurance status were observed, these general management trends were seen in all groups. CONCLUSIONS: Changes in the utilization of radiation and surgery may reflect the increasing surgical involvement of gynecologic oncologists in the management of early stage cervical cancer, rather than significant alterations in the demographics of the disease. Although brachytherapy is recognized as an important component of radiation treatment, some patients may not receive the potential benefit of this modality. Despite controversy concerning its efficacy, the use of adjuvant systemic chemotherapy to supplement local treatment modalities appears to be increasing rapidly.  相似文献   
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There are two distinct types of MIMD (Multiple Instruction, Multiple Data) computers: the shared memory machine, e.g. Butterfly, and the distributed memory machine, e.g. Hypercubes, Transputer arrays. Typically these utilize different programming models: the shared memory machine has monitors, semaphores and fetch-and-add; whereas the distributed memory machine uses message passing. Moreover there are two popular types of operating systems: a multi-tasking, asynchronous operating system and a crystalline, loosely synchronous operating system.

In this paper I firstly describe the Butterfly, Hypercube and Transputer array MIMD computers, and review monitors, semaphores, fetch-and-add and message passing; then I explain the two types of operating systems and give examples of how they are implemented on these MIMD computers. Next I discuss the advantages and disadvantages of shared memory machines with monitors, semaphores and fetch-and-add, compared to distributed memory machines using message passing, answering questions such as “is one model ‘easier’ to program than the other?” and “which is ‘more efficient‘?”. One may think that a shared memory machine with monitors, semaphores and fetch-and-add is simpler to program and runs faster than a distributed memory machine using message passing but we shall see that this is not necessarily the case. Finally I briefly discuss which type of operating system to use and on which type of computer. This of course depends on the algorithm one wishes to compute.  相似文献   

104.
Under ferroelectric switching in Pb(Zr2Ti)O3 (PZT) ceramics, we demonstrate that oxygen gas is emitted and degrades electrode microstructure. The oxygen is a direct result of the defect chemistry associated with superoxidation which is established during the processing of the ceramics. Under high alternating electric fields, electron injection into the ceramic surface induces a reduction process, and surface layers are believed to change from a p-type electronic compensation to an ionic compensation of oxygen vacancies and A-site lead vacancies. During this process, we noticed progressive changes in capacitance, loss, remnant polarization, and coercive field. The wider implications of this observation for PZT thin film nonvolatile memories are discussed in brief.  相似文献   
105.
International diagnostic criteria for depression have been elaborated in order to standardize and to facilitate diagnostic assessment. The findings of the present survey suggest that general practitioners (GPs) do accurately assess the individual depressive symptoms required to fulfill international diagnostic criteria for depressive syndromes. Training GPs to use these diagnostic criteria may be a way of improving recognition and diagnosis of depression in general practice.  相似文献   
106.
We tested Beck's (1983) hypothesis that depressive symptoms occur when an individual experiences a negative life event that specifically matches the individual's personal motivational vulnerability. Ninety-eight undergraduates completed measures of depression level, recent life events, and sociotropic and autonomous achievement motivations. Consistent with the theory, sociotropy was associated with depression level and also served as a moderator of the relations between depression and frequency of recent negative social events. However, sociotropy also demonstrated nonpredicted interactive effects with negative events categorized a priori as autonomy related. Autonomy was unrelated to depression and showed no evidence of being a vulnerability to any type of life event. The findings generally support the value of examining the role in depression of interactions between personality characteristics and life events, although they do not support the specific matching predictions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
Subsyllabic awareness was investigated with a word synthesis task. Children from kindergarten, 1st grade, and 2nd grade attempted to blend auditorily presented CCVC word segments (where C?=?consonant and V?=?vowel) to produce words. Subsyllabic segmentation and presentation rate of the word segments were varied, and the dependent measure was percentage correct in each condition. Several posttests were administered to measure the children's preexisting ability to recognize visually presented consonants, consonant clusters, rimes, and words. Second graders performed better than 1st graders, who in turn performed better than kindergarteners. Performance of all children was best on words that were segmented between onset and rime and poorest for words that were segmented into individual phonemes. Performance for word segrnents that were presented at the fast rate was better than for those presented at the slow rate. The authors suggest that preliterate children are able to manipulate suprasegmental units such as onset and rime, and that those units should be emphasized in early reading instruction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Cancer-related services are consuming ever-increasing health resources; along with this trend, health care costs are rising. As health care planners, researchers, and policymakers formulate strategies to meet this challenge, they are looking to cancer registries and the health information system built around them as collectors of the most extensive information regarding cancer treatment in the U.S. Currently, there are multiple programs collecting and reporting data regarding cancer incidence, morbidity, mortality, and survival. This report profiles cancer surveillance efforts in the U.S. and describes the National Coordinating Council for Cancer Surveillance, which was organized in 1995 to facilitate a collaborative approach among the organizations involved.  相似文献   
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