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1.
从手术签字审视医疗活动中道德与法律之冲突   总被引:3,自引:1,他引:2  
手术签字不应成为实施手术的必要条件,手术治疗及其他医疗活动中道德与法律之冲突有其产生的理论和现实根源,其实质是利益冲突。合情不合法与合法不合情是道德与法律冲突的两种具体情形。单纯的道德谴责或责任追究无助于,中突的解决,完善法律、提升道德、调适利益是避免及减少冲突的有效途径。  相似文献   

2.
The Holley-Guilford G index for 2×2 contingency tables has spatial properties which suggest that, as with other such indices, problems may arise in factor analysis of G matrices. Two response models—Guttman's Simplex and the Coombs-Kao conjunctive case—are used to provide data for exploring the behaviour of G. In particular, the claim that G equates person means and variances in Q analysis is not substantiated.  相似文献   

3.
Cognitive Outcome in Acute Sporadic Encephalitis   总被引:5,自引:0,他引:5  
Acute encephalitis is an inflammation of the brain parenchyma. In the United States, 20,000 cases occur yearly. A variety of cognitive deficits, often the sole cause of disability, may persist after the acute stage. Still, infectious diseases tend to be covered only briefly in neuropsychological handbooks. Recent literature demonstrates the heterogeneity of both amnestic disorders and the outcome following encephalitides. Herpes Simplex virus (HSV), the most common single etiology of sporadic encephalitis, usually causes the most severe symptoms. Modern antiviral medication, however, seems to improve the cognitive outcome. Much less is known about non-HSV encephalitides, where both mild and severe defects have been observed. This article summarizes the current knowledge and also calls upon a more active neuropsychological research in the area.  相似文献   

4.
During cognitive processing, the various cortical areas, with specialized functions, supply for different tasks. In most cases then, the information flows are processed in a parallel way by brain networks which work together integrating the single performances for a common goal. Such a step is generally performed at higher processing levels in the associative areas. The frequency range at which neuronal pools oscillate is generally wider than the one which is detectable by bold changes in fMRI studies. A high time resolution technique like magnetoencephalography or electroencephalography is therefore required as well as new data processing algorithms for detecting different coherent brain areas cooperating for one cognitive task. Our experiments show that no algorithm for the inverse problem solution is immune from bias. We propose therefore, as a possible solution, our software LOCANTO (LOcalization and Coherence ANalysis TOol). This new package features a set of tools for the detection of coherent areas. For such a task, as a default, it employs the algorithm with best performances for the neural landscape to be detected. If the neural landscape under attention involves more than two interacting areas the SLoreta algorithm is used. Our study shows in fact that SLoreta performance is not biased when the correlation among multiple sources is high. On the other hand, the Beamforming algorithm is more precise than SLoreta at localizing single or double sources but it gets a relevant localization bias when the sources are more than three and are highly correlated.  相似文献   

5.
Prior research on cognitive skill learning has shown that algorithmic and direct memory retrieval strategies are not executed in parallel if the algorithm entails a series of long-term memory (LTM) retrieval steps (as in the case, for example, of mental arithmetic). This phenomenon has been hypothesized to reflect a bottleneck in LTM retrieval processes that forces a strategy choice during an early stage of processing. Here, we investigate simple perceptual–motor algorithms that involve no memory retrieval steps, a largely unexplored case in which parallel strategy execution models remain viable. Pronounced strategy interference was again observed, albeit interference that was different in important respects from that observed for LTM retrieval algorithms. It appears that neither parallel nor choice models, as developed to date, are sufficient as a generalized theory of this skill learning phenomenon. Issues central to the development of a more comprehensive theory are discussed.  相似文献   

6.
Within the context of the psychological refractory period (PRP) paradigm, we developed a general theoretical framework for deciding when it is more efficient to process two tasks in serial and when it is more efficient to process them in parallel. This analysis suggests that a serial mode is more efficient than a parallel mode under a wide variety of conditions and thereby suggests that ubiquitous evidence of serial processing in PRP tasks could result from performance optimization rather than from a structural bottleneck. The analysis further suggests that the experimenter-selected distribution of stimulus onset asynchronies (SOAs) influences the relative efficiency of the serial and parallel modes, with a preponderance of short SOAs favoring a parallel mode. Experiments varying the distribution of SOAs were conducted, and the results suggest that there is a shift from a more serial mode to a more parallel mode as the likelihood of short SOAs increases.  相似文献   

7.
A simple view, which dates back to Turing, proposes that complex cognitive operations are composed of serially arranged elementary operations, each passing intermediate results to the next. However, whether and how such serial processing is achieved with a brain composed of massively parallel processors, remains an open question. Here, we study the cognitive architecture for chained operations with an elementary arithmetic algorithm: we required participants to add (or subtract) two to a digit, and then compare the result with five. In four experiments, we probed the internal implementation of this task with chronometric analysis, the cued-response method, the priming method, and a subliminal forced-choice procedure. We found evidence for an approximately sequential processing, with an important qualification: the second operation in the algorithm appears to start before completion of the first operation. Furthermore, initially the second operation takes as input the stimulus number rather than the output of the first operation. Thus, operations that should be processed serially are in fact executed partially in parallel. Furthermore, although each elementary operation can proceed subliminally, their chaining does not occur in the absence of conscious perception. Overall, the results suggest that chaining is slow, effortful, imperfect (resulting partly in parallel rather than serial execution) and dependent on conscious control.  相似文献   

8.
提出了一种改进的分层并行演化算法。针对传统算法中"同构子种群"和"同步通信"所引发的问题,新算法构建了异构模型,并将各子种群充分连接。子种群一旦满足迁移条件,便可按照预设的迁移模式实施异步迁移。仿真实验结果表明,本文提出的新算法有效地解决了"征服问题"和"无效问题",避免了算法的过早收敛,提高了算法的效率。  相似文献   

9.
生殖器疱疹是单纯疱疹病毒感染生殖器部位皮肤黏膜所引起的炎症性疾病,是常见的性传播性疾病之一。近年来,随着其在人群中的流行率的不断增高,在国内已成为一个令人关注的公共卫生问题。本文就其病原学、流行状况、传播和潜在的危险性作一概述,并分析了在其诊疗过程中的伦理问题及相关的对策。  相似文献   

10.
The purpose of the paper is to describe and analyse the prevalence of parallel sexual relationships among adult Norwegians in terms of social background variables, possibility factors and motivational factors. Data stem from two cross-sectional, postal questionnaire surveys in 1987 and 1992 on two separate representative samples of 10,000 Norwegians aged between 18 and 60. The results showed that 16% of the respondents reported one or more parallel sexual relationships. The prevalence of parallel sexual relationships increased with possibility factors, such as the number of travelling days and population density. Among motivational factors, parallel sexual relationships increased with the number of years married/cohabiting, except for those married the longest. It decreased with increasing age of first intercourse, and increased with the number of partners before the last partnership. Of those not satisfied with coital frequency with their permanent partner, 22% had parallel sexual relationship experience compared to 12% among those who were satisfied. Furthermore, more men than women reported parallel sexual relationships; respondents with higher levels of education more often reported parallel sexual activity than those with lower level of education; and subjects born between 1937 and 1956 reported more parallel sexual activity than the other cohorts. When controlled for the number of years married/cohabiting, the predicted trend suggests that for the cohorts born up to 1970, men and women with lower and higher levels of education have become more similar as regards parallel sexual behaviour. © 1998 John Wiley & Sons, Ltd.  相似文献   

11.
Abstract

This study describes a patient (SE) with temporal lobe injury resulting from Herpes Simplex Encephalitis, who displayed a previously unreported impairment in which his knowledge of associative and functional attributes of animals was disproportionately impaired by comparison with his knowledge of their sensory attributes (including their visual properties and characteristic sounds). His knowledge of man-made objects was preserved. A striking aspect of the present case was that the patient remained able to name many animals from their pictures, despite making gross errors in generating associative information about these same animals. This suggests that a semantic representation incorporating stored sensory knowledge may be sufficient for naming (at least for biological categories) and associative information may be unnecessary. Semantic knowledge may normally incorporate more information than is necessary for identification. SE's errors were found to be confabulatory and reconstructive in nature and it is argued that this aspect of his performance challenges passive conceptions of semantic memory couched in terms of a catalogue of stored representations. It is proposed that the patient's disorder affects a dynamic, constructive, and inferential component of his knowledge base, and that this component is sensitive to semantic category.  相似文献   

12.
Five patients with a diagnosis of Herpes Simplex Virus Encephalitis (HSVE) underwent neuropsychological assessment to explore the integrity of their visual perceptual abilities. Selective deficits affecting different levels of the recognition processing were found; impaired recognition abilities were also influenced by selective task requirements, which resulted either in facilitatory or constraining effects on patients' performance. A theoretical model of object recognition (Humphreys & Riddoch, 1987) was taken into account to explain patients' performance. Further, the role of specific components of visual processing was evidenced in explaining the performance of patients affected by HSVE.  相似文献   

13.
基于OpenMP的并行遗传算法探讨   总被引:2,自引:0,他引:2  
目前主流CPU厂商都在致力发展多核处理器,增加芯片支持的并行能力,从而突破技术壁垒,提升运算速度。本文主要探讨近来流行的多核计算技术,介绍一种重要的工业标准OpenMP,以及对基于OpenMP的并行编程模式进行剖析。OpenMP编程主要是通过软件多线程来提升PC应用软件的功能和性能。随后以遗传算法求解TSP问题为例子实现了OpenMP多线程应用程序。  相似文献   

14.
Prospective remembering was studied in a group of patients who suffered from Herpes Simplex Encephalitis (HSE). All patients showed a marked deficit in executing intentions for future actions under all the given constraints. The deficit extended to both time- and event-based intentions. The analysis of errors showed somewhat different patterns and some dissociations with evidence for selective preservation or damage to specific components involved in prospective remembering. These patients, in fact, may fail because of a difficulty in taking into account all given constraints or in activating stored intentions and in forming intentions or in remembering the content of the actions. Time- and event-based tasks seem to show different sources of errors also in the same patient.  相似文献   

15.
Abstract

No studies investigating the relationship of herpesviruses and psychological distress in Human Immunodeficiency Virus (HIV) infection are available in the literature. Antibody titers for Cytomegalovirus (CMV), Epstein-Barr (EBV) and Herpes Simplex virus (HSV) were assessed from sera drawn at the lime of psychological testing for one hundred HIV seropositive subjects. Increased psychological distress was correlated with increased titers of antibody to HSV, but not to CMV or EBV. Psychological distress may play a role in the devastating HSV infections experienced by immune deficient individuals. A stress mediated reactivation/potentiation hypothesis is discussed, where distress reactivates latent HSV which in turn potentiates HIV replication. These results may have implications for treatment of individuals co-infected with HIV and HSV.  相似文献   

16.
It is argued that some of the phenomena identified with analog processes by Shepard can be understood as resulting from a parallel-process algorithm running on a processor having many individual processing elements and a restricted communication structure. In particular, an algorithm has been developed and implemented which models human behavior on Shepard's object rotation and comparison task. The algorithm exhibits computation times which increase linearly with the angle of rotation. Shepard found a similar linear function in his experiments with human subjects. In addition, the intermediate states of the computation are such that if the rotation process were to be interrupted at any point, the object representation would correspond to that of the actual object at a position along the rotation trajectory. The computational model presented here is governed by three constraining assumptions: (a) that it be parallel: (b) that the communication between processors be restricted to immediate neighbors: (c) that the object representation be distributed across a large fraction of the available processors. A method of diagnosing the correct axis of rotation is also presented.  相似文献   

17.
The computational power of massively parallel networks of simple processing elements resides in the communication bandwidth provided by the hardware connections between elements. These connections can allow a significant fraction of the knowledge of the system to be applied to an instance of a problem in a very short time. One kind of computation for which massively parallel networks appear to be well suited is large constraint satisfaction searches, but to use the connections efficiently two conditions must be met: First, a search technique that is suitable for parallel networks must be found. Second, there must be some way of choosing internal representations which allow the preexisting hardware connections to be used efficiently for encoding the constraints in the domain being searched. We describe a general parallel search method, based on statistical mechanics, and we show how it leads to a general learning rule for modifying the connection strengths so as to incorporate knowledge about a task domain in an efficient way. We describe some simple examples in which the learning algorithm creates internal representations that are demonstrably the most efficient way of using the preexisting connectivity structure.  相似文献   

18.
The parallel lines illusion change effect (discovered by the authors) was studied: When the plane of a parallel-lines illusion figure intersects obliquely with the line of vision and the figure is rotated, using an imaginary perpendicular line between the parallel lines as the axis, the smaller the intersecting angle, the more the illusory effect decreases, until it disappears. If the illusion figure is rotated and any one of the parallel lines is used as the axis, then the smaller the intersecting angle, the greater the illusory effect. The parallel lines illusion change effect may be applicable to the study of geometric-figure illusions.  相似文献   

19.
Although it is generally recognized that the concurrent performance of two tasks incurs costs, the sources of these dual-task costs remain controversial. The serial bottleneck model suggests that serial postponement of task performance in dual-task conditions results from a central stage of response selection that can only process one task at a time. Cognitive-control models, by contrast, propose that multiple response selections can proceed in parallel, but that serial processing of task performance is predominantly adopted because its processing efficiency is higher than that of parallel processing. In the present study, we empirically tested this proposition by examining whether parallel processing would occur when it was more efficient and financially rewarded. The results indicated that even when parallel processing was more efficient and was incentivized by financial reward, participants still failed to process tasks in parallel. We conclude that central information processing is limited by a serial bottleneck.  相似文献   

20.
The problems of access—retrieving linguistic structure from some mental grammar —and disambiguation—choosing among these structures to correctly parse ambiguous linguistic input—are fundamental to language understanding. The literature abounds with psychological results on lexical access, the access of idioms, syntactic rule access, parsing preferences, syntactic disambiguation, and the processing of garden-path sentences. Unfortunately, it has been difficult to combine models which account for these results to build a general, uniform model of access and disambiguation at the lexical, idiomatic, and syntactic levels. For example, psycholinguistic theories of lexical access and idiom access and parsing theories of syntactic rule access have almost no commonality in methodology or coverage of psycholinguistic data. This article presents a single probabilistic algorithm which models both the access and disambiguation of linguistic knowledge. The algorithm is based on a parallel parser which ranks constructions for access, and interpretations for disambiguation, by their conditional probability. Low-ranked constructions and interpretations are pruned through beam-search; this pruning accounts, among other things, for the garden-path effect. I show that this motivated probabilistic treatment accounts for a wide variety of psycholinguistic results, arguing for a more uniform representation of linguistic knowledge and for the use of probabilistically-enriched grammars and interpreters as models of human knowledge of and processing of language.  相似文献   

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