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261.
The degree of structural and functional specialization that differentiates between upper and lower limb use in humans is quite unparalleled among primates. It is argued that less neural resources are devoted to leg and foot control than to arm and hand control, and that this aspect of lower limb innervation, together with the uniquely restricted use of the lower limb, renders lower limb function more sensitive to general neural insult. In addition, the status of leg and foot control differs from that of arm and hand control both early in life and during the later years of decline.  相似文献   
262.
Hardware is described that permits bidirectional transfer of data between the Commodore 64 and an IBM-compatible PC. Commercial terminal programs can be used to transmit data. The hardware, which can be constructed for less than $15, opens up several opportunities for making good use of the cost-effective C64 computer.  相似文献   
263.
Abstract— In our discussion of the articles in this Special Section, we ask how well the various methods employed in these investigations can be made to converge on a common issue. We review how current evidence from positron emission tomography, studies of event-related potentials, cognitive methods, lesion studies, and network models relates to the mental processing of an ambiguous word. While many puzzles remain, we are impressed by the promising possibility of bringing these different methods together to deal with an issue central to cognition.  相似文献   
264.
Romanians suffered incredible deprivations of every sort during the decades of Communist dictatorship. Most of the country’s 1,000 psychiatrists, and most of their patients, were victimized by the political system. A few psychiatrists actively engaged in practices amounting to torture. Many, however, became willing or unwilling participants in the political abuse of their profession. Such political abuses were fostered by abusive legislation and abusive law enforcement by the secret police. Abuses included: mass detentions in psychiatric hospitals of dissidents and political undesirables; abusive interpretation of the laws in detaining persons not suffering from mental illness; false, politically motivated diagnoses and treatment; and detention in secret facilities. While there are honest efforts to come to grips with the past, to compensate victims of psychiatric abuse, and to institute proceedings against abusers, there is also much resistance to reform. Reform-minded Romanian psychiatrists deserve the support of their western colleagues in the effort to restore Romanian psychiatry. In particular, professional colleagues all over the world are asked to comment on the draft law currently pending before the Romanian parliament, which is intended to restore the rule of law to the practice of psychiatry in Romania. Report of a consultative mission to Bucharest, on behalf of the Geneva Initiave on Psychiatry, 7 June to 12 June 1992, by Nanci Adler, Historian-Sovietologist, Geneva Initiative on Psychiatry, Amsterdam, The Netherlands; G.O.W. Mueller, Distinguished Professor of Criminal Justice, Rutgers — The State University of New Jersey, U.S.A.; Mohammed Ayat, Professor of Criminology and Penal Law, Université de Fes, Faculté des Sciences Juridiques, Economiques et Sociales, FEs, Morocco. The Geneva Initiative on Psychiatry is a nongovernmental, nonprofit organization, dedicated to the introduction and preservation of ethical practices in the psychiatric profession, in accordance with medical ethics, the Universal Declaration of Human Rights, and U.N. standards and guidelines. Headquartered in Amsterdam, the organization is currently providing technical and financial assistance to the newly established free, independent, democratic psychiatric associations in Russia, Ukraine, Romania, and other countries. The General Secretary of the organization is Robert van Voren; the board is composed of professionals from some twenty countries. This article was based on meetings at governmental and parliamentary offices, nongovernmental organizations, and embassies as well psychiatric institutions with, among others, the following persons: Dr. Lucian Alexandrescu, V-P Radu Ciuceanu, Mr. Comsa, Proc. Gen’l. Ulpiu Cereceanu, Mr. Nistor Cristea, Mr. Dinu Ianculescu, Prof. Dr. George Ionescu, Miss Cristina Luzoscu, Dr. Zaharia Nicolae, Mr. Iancu Petrescu, Dr. Dan Prelipcianu, Min. Mircea Ionescu-Quintus, Dr. Aurel Romila, Av. Nicolae Stefanescu-Draganesti, Dir. Dr. Tomescu, Dr. Alexandru Trifan, Dr. Valeriu Tuculescu, and numerous victims, diplomats, and Romanian citizens.  相似文献   
265.
The first two books on behavior analysis (Skinner, 1938; Keller & Schoenfeld, 1950) had chapter-length coverage of motivation. The next generation of texts also had chapters on the topic, but by the late 1960s it was no longer being given much treatment in the behavior-analytic literature. The present failure to deal with the topic leaves a gap in our understanding of operant functional relations. A partial solution is to reintroduce the concept of the establishing operation, defined as an environmental event, operation, or stimulus condition that affects an organism by momentarily altering (a) the reinforcing effectiveness of other events and (b) the frequency of occurrence of that part of the organism's repertoire relevant to those events as consequences. Discriminative and motivative variables can be distinguished as follows: The former are related to the differential availability of an effective form of reinforcement given a particular type of behavior; the latter are related to the differential reinforcing effectiveness of environmental events. An important distinction can also be made between unconditioned establishing operations (UEOs), such as food deprivation and painful stimulation, and conditioned establishing operations (CEOs) that depend on the learning history of the organism. One type of CEO is a stimulus that has simply been paired with a UEO and as a result may take on some of the motivative properties of that UEO. The warning stimulus in avoidance procedures is another important type of CEO referred to as reflexive because it establishes its own termination as a form of reinforcement and evokes the behavior that has accomplished such termination. Another CEO is closely related to the concept of conditional conditioned reinforcement and is referred to as a transitive CEO, because it establishes some other stimulus as a form of effective reinforcement and evokes the behavior that has produced that other stimulus. The multiple control of human behavior is very common, and is often quite complex. An understanding of unlearned and learned establishing operations can contribute to our ability to identify and control the various components of such multiple determination.  相似文献   
266.
In this paper a method is outlined for measuring the diversity of the results of applied R&D with the use of IPC (International Patent Classification). The method has been tested in the contexts of the academic physical, engineering, and chemical institutes. The trend of applied research at a given institute increases both at the level of classes and subclasses, and at the IPC level. Inventions developed within specializations at each institute have a greater efficiency than other forms of inventive activity. The objective was to seek the optimal extent of diversification of applied R&D, which would simultaneously ensure the preservation of the scientific specialization of an institute, the high level of scientific research associated with developing innovations, and the high overall efficiency of each institute.  相似文献   
267.
Finland has followed the Scandinavian model of the welfare state in which the level of state activism is high, the economic pressures on the scientific activities are strong, and the left-wing parties and the Center Party have formulated the main ideas. In the 1970s welfare ideology was adopted in science policy by emphasizing the promotion of socially relevant scientific activities and the expansion of the university system as a means of effecting equal opportunity. Currently, the trend is toward a mixed welfare economy. Programs have been prepared in spite of the radical cut in government expenditure, and without a consideration of the long-term consequences.  相似文献   
268.
269.
In contemporary American scholarship, interpretation of Aristotle'sRhetoric has become the locus of sustained and sharp controversy. Differing views of theRhetoric and its significance have become tokens in a more general dispute about what rhetoric is or ought to be. This essay examines three central issues that have emerged in this larger arena of controversy: the relationship between Aristotelian and Platonic conceptions of rhetoric, the relationships among rhetoric, ethics, and epistemology in Aristotle, and the placement of rhetoric within Aristotle's system of arts and sciences.  相似文献   
270.
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