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81.
Assessment of risk is one of the key issues in the field of responsible conduct of research which covers discourses of research ethics and research integrity. The principle of minimizing risks and balancing of risks and benefits is one of the main requirements of research ethics. In addition, the content of informed consent that is another fundamental principle of research ethics derives from the assessment of risks and benefits related to a particular research project. Risk assessment also plays a crucial role in methodological design of the research project. This is an important point where research ethics and research integrity discourses overlap. Firstly, because the choice of a control group (e.g., placebo control) is a key ethical issue related to the protection of the research subjects' interests. Secondly, because the quality of the research data, that is one of the key elements of research integrity, is closely connected to the choice of research methodology as well. The problem of biased interpretation or manipulation of risk related features of biomedical research should also be taken into account. Despite the importance of the concept of risk to the field of biomedical research, its relevance has not yet attracted a sufficient attention in the responsible conduct of research debate.  相似文献   
82.
The Helsinki Declaration is a very important document regarding the protection of patients’ rights in clinical trials and one of the fundamental sources of operational principles for every ethics committee. Although they have been updated, the international guidelines for ethics committees continually fail to address certain issues pertaining to the protection of patients’ rights in clinical trials. These issues include, most significantly, the method of electing ethics committees (a free, secret ballot should be preferred to direct appointment), the avoidance of conflict of interest during the election of ethics committee members, and the necessary insurance coverage for the participants of clinical trials. Polish law should, on the other hand, be developed in such way as to not limit the effectiveness of ethics committees in protecting patients’ rights in clinical trials. The ideal solution would be to draft a uniform law concerning not only clinical trials, but all medical experiments. The opinions of experts who have been reviewing medical research projects for several years may prove to be especially valuable in this setting. This paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005. The author is Chairman, Bioethics Committee of the Warsaw Regional Chamber of Physicians and Dentists.  相似文献   
83.
Medicine is a scientific discipline, but it is sometimes difficult to separate what is scientific and what is a clinical, practical activity. Man is the object, but he is always the subject of medical research and therefore these two elements become closely bound together by a thread of moral interdependencies. Every mentor of a young academic and all institutions dealing with the teaching of and research into medicine must understand multidimensional, multifaceted, and multilevel aspects of their activity and give them due regard in the educational process. The educational mission of an academic institution and of the teacher working there may be summed up in one phrase: Teach thinking! At the same time, the task of a school and the individual mentor is to teach the student to distinguish personal freedom from a lack of the feeling of responsibility. The medieval principle “Universitas magistrorum et scholarium”, and thus the corporation, the community of teachers and students, has not lost any of its relevance and value today. The situation is, in its far-reaching consequences, tragic in which the “insufficiently tutored teach”. Both physician and teacher, and especially physician-teacher, are not only professions, but also callings. This paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005.  相似文献   
84.
126 leaders and 624 employees were sampled to test the relationship between sources of motivation and conflict management styles of leaders and how these variables influence effectiveness of leadership. Five sources of motivation measured by the Motivation Sources Inventory were tested-intrinsic process, instrumental, self-concept external, self-concept internal, and goal internalization. These sources of work motivation were associated with Rahim's modes of interpersonal conflict management-dominating, avoiding, obliging, complying, and integrating-and to perceived leadership effectiveness. A structural equation model tested leaders' conflict management styles and leadership effectiveness based upon different sources of work motivation. The model explained variance for obliging (65%), dominating (79%), avoiding (76%), and compromising (68%), but explained little variance for integrating (7%). The model explained only 28% of the variance in leader effectiveness.  相似文献   
85.
Past research has identified visual objects as the units of information processing in visual short-term memory (VSTM) and has shown that two features from the same object can be remembered in VSTM as well (or almost as well) as one feature of that object and are much better remembered than the same two features from two spatially separated objects. It is not clear, however, what drives this object benefit in VSTM. Is it the shared spatial location (proximity), the connectedness among features of an object, or both? In six change detection experiments, both location/proximity and connectedness were found to be crucial in determining the magnitude of the object benefit in VSTM. Together, these results indicate that location/proximity and connectedness are essential elements in defining a coherent visual object representation in VSTM.  相似文献   
86.
Preschoolers' theory-of-mind development follows a similar age trajectory across many cultures. To determine whether these similarities are related to similar underlying ontogenetic processes, we examined whether the relation between theory of mind and executive function commonly found among U.S. preschoolers is also present among Chinese preschoolers. Preschoolers from Beijing, China (N= 109), were administered theory-of-mind and executive-functioning tasks, and their performance was compared with that of a previously studied sample of U.S. preschoolers (N= 107). The Chinese preschoolers outperformed their U.S. counterparts on all measures of executive functioning, but were not similarly advanced in theory-of-mind reasoning. Nonetheless, individual differences in executive functioning predicted theory of mind for children in both cultures. Thus, the relation between executive functioning and theory of mind is robust across two disparate cultures. These findings shed light on why executive functioning is important for theory-of-mind development.  相似文献   
87.

Discontinuous precipitation in a two-phase Zn-rich Zn-6.3at.%Ag alloy has been studied. It has been shown that the eta/epsilon interphase boundaries have the ability to initiate discontinuous precipitation as do the eta/eta grain boundaries. The back-polishing method is used to show the interconnection between a discontinuous precipitate colony and the eta/epsilon interphase boundary. The reaction front velocity of discontinuous precipitation initiated at the eta/eta grain boundary is 12-90% higher than that of discontinuous precipitation initiated at the eta/epsilon interphase boundary under various ageing temperatures.  相似文献   
88.

We present an analysis and results on the homogeneous nucleation of a dislocation loop under stress in a perfect crystal. By using a variational boundary integral method in the Peierls-Nabarro framework, we have determined the saddle-point configurations of embryonic dislocation loops and their associated activation energies under stress levels up to the ideal shear strength. The high-energy barriers under the usual levels of applied shear stresses, differing markedly from the ideal shear strength, confirm the widely held view that thermal motion should play no role in such nucleation. The result provides means for more definitive solutions of fundamental problems involving homogeneous nucleation of dislocation loops and has significant implications for models based on the mechanism of nucleation of dislocations from a perfect crystal.  相似文献   
89.
The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning.  相似文献   
90.
The mechanical softening behaviour of micrometre-scale metals (free-standing metal foils and wires) with decreasing either the geometrical or the microstructural scale (i.e. the smaller, the weaker) has recently been reported. Here, we present a mechanism-based model to understand the softening behaviour, which is based on competition between the effects of surface grain relaxation and the interior grain strengthening effect. The model describes well the yield stress of Cu foils with different ratios of the thickness to grain size.  相似文献   
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