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191.
192.
A theory of definitions which places the eliminability and conservativeness requirements on definitions is usually called the standard theory. We examine a persistent myth which credits this theory to Le?niewski, a Polish logician. After a brief survey of its origins, we show that the myth is highly dubious. First, no place in Le?niewski's published or unpublished work is known where the standard conditions are discussed. Second, Le?niewski's own logical theories allow for creative definitions. Third, Le?niewski's celebrated ‘rules of definition’ lay merely syntactical restrictions on the form of definitions: they do not provide definitions with such meta-theoretical requirements as eliminability or conservativeness. On the positive side, we point out that among the Polish logicians, in the 1920s and 1930s, a study of these meta-theoretical conditions is more readily found in the works of ?ukasiewicz and Ajdukiewicz.  相似文献   
193.
This study investigated the internal reliability, temporal stability and plasticity of commonly used measures of inhibition-related functions. Stop-signal, go/no-go, antisaccade, Simon, Eriksen flanker, Stroop and Continuous Performance tasks were administered twice to 23 healthy participants over a period of approximately 11 weeks in order to assess test–retest correlations, internal consistency (Cronbach’s alpha), and systematic between as well as within session performance changes. Most of the inhibition-related measures showed good test–retest reliabilities and internal consistencies, with the exception of the stop-signal reaction time measure, which showed poor reliability. Generally no systematic performance changes were observed across the two assessments with the exception of four variables of the Eriksen flanker, Simon and Stroop task which showed reduced variability of reaction time and an improvement in the response time for incongruent trials at second assessment. Predominantly stable performance within one test session was shown for most measures. Overall, these results are informative for studies with designs requiring temporally stable parameters e.g. genetic or longitudinal treatment studies.  相似文献   
194.
Abstract

Pituitary-adrenal axis was studied in terms of Type A behaviour, hostility and vital exhaustion among 69 healthy middle-aged men. The results showed that psychological factors could explain a significant proportion of the biologically manipulated responses of HPA axis, but they worked in different ways. Type A behaviour was related to a high level of mean basal ACTH and a low level of cortisol response to ACTH stimulation after dexamethasone suppression; hostility was related to a high level of mean basal cortisol and a high cortisol in cortisol/ACTH ratio, while vital exhaustion was characterized by a low level of mean basal ACTH and a decreased ACTH in relation to cortisol. The adrenocortical patterns, i.e. a high ACTH-low cortisol; a high cortisol; and a low ACTH-low mean basal cortisol, as related to Type A behaviour, hostility and exhaustion, respectively, are in line with the traditional physiological stress model and suggest that different adrenocortical responses might be able to identify different mental stress processes. Sense of control has been suggested to be a key concept for psychological understanding of this finding.  相似文献   
195.
Single-crystal (0 0 0 1) GaN samples have been deformed with a Vickers indenter at room temperature using loads in the range from 0.02 to 4.90 N. Dislocations and cracks at the indentations were examined by means of scanning electron microscopy, cathodoluminescence, light microscopy and transmission electron microscopy. Geometrical relations could be found between the dislocation arrangement, cracks and the orientation of the indenter. The orientation of the indenter has only a slight effect on the dislocation pattern, but the crack system is predominantly determined by the symmetry and the orientation of the indenter.  相似文献   
196.
This article describes a design strategy deployed in developing ultra-ductile Mg alloys based on a microalloying concept, which aims to restrict grain growth considerably during alloy casting and forming. We discuss the efficiency of the design approach, and evaluate the resulting microstructural and mechanical properties. After processing, the so-designed alloys ZQCa3 (Mg–3Zn–0.5Ag–0.25Ca–0.15Mn, in wt.%) and ZKQCa3 (Mg–3Zn–0.5Zr–0.5Ag–0.25Ca–0.15Mn, in wt.%) reveal very fine grains (<10 µm), high ductility (elongation to fracture of up to 30%) at moderate strength or high strength (ultimate tensile strength of up to 350 MPa) at reasonable ductility. These properties are explained based on thermodynamic modelling, microstructure analysis including transmission electron microscopy studies, and microstructural and mechanical testing after annealing, and are compared to a related commercial alloy (ZK31).  相似文献   
197.
We have fabricated a molecular organic light-emitting device comprising indium–tin oxide/a molecular organic layer/aluminum in which the organic layer is a green fluorescent protein. The device exhibits peak external quantum and power efficiencies of 8?±?0.2% and 13?±?0.7?lm?W???1 at a current of J?=?1.5?A?m?2, respectively. In addition, the turn-on voltage is 2.5?V for 1?cd?m?2 and the maximum luminance achieved is 1275?cd?m?2. This good performance can be explained by the presence of singlet-excited states, leading to a high internal efficiency.  相似文献   
198.
Abstract

Creationism is a worldview that does not accept the undirected formation and development of life but requires intelligent (supernatural) intervention. We analyzed texts representing Young Earth creationism (YEC) and intelligent design (ID) for their theological content and implications by assessing their position in central issues of systematic theology. YEC proponents emphasize the young age of the Earth and the necessity of literal interpretation of Genesis as prerequisites for the Fall and redemption. ID accepts the geological age of the planet, but requires intervention during evolution. YEC maintained the traditional characteristics of the Christian God (omnipotence, omniscience, benevolence), while some ID authors refused to speculate on the nature of the alleged designer. YEC authors utilized reinterpretation of scientific data as evidence for creation and to legitimize their belief in the historicity of Genesis. This could be regarded a form of scientism. YEC theodicy concentrated on the Fall as the cause of evil and the eschatological resolution of suffering. In contrast, ID proponents attempted to solve theodicy by compensated benefits of, e.g., pain. ID did not take a clear stand regarding salvation and ecclesiology, but YEC authors considered the acceptance of evolutionary theory and Christian faith to be mostly inconsistent. YEC doctrine differed from major Christian denominations by accepting scientific evidence as a proof for the historicity of Genesis and showed signs of exclusivity regarding evolutionary proponents. In ID, no satisfactory theodicy could be observed and some ID theorists could be classified as agnostics because of doubting the identity of the designer and by limiting God's omnipotence and benevolence. Both YEC and ID demonized evolutionary theory and its proponents. Creationism seems to be on its way to becoming a new kind of denomination or an emerging novel religion.  相似文献   
199.
Abstract

Vertigo and dizziness may cause considerable discomfort and feelings of uncertainty. It is no surprise that vertigo is the most disabling symptom in Menière's disease, an inner ear disorder. The other two cardinal symptoms are tinnitus and hearing impairment. In this study, one severely disabled woman was treated with a cognitive-behavioural treatment comprising, among other components, relaxation training, stabilization of gaze, cognitive restructuring and behavioural task setting. The patient responded well to the treatment, during which her vertigo attacks disappeared. During the follow-up period, she experienced vertigo attacks again, but after two booster sessions the vertigo attacks vanished for the rest of the follow-up period. The results are further discussed.  相似文献   
200.
ABSTRACT

This study aimed to test the cognitive and affective benefits gained through the provision of educational materials at workstations in the Wilhelma Zoo in Stuttgart, Germany. Structured learning materials were developed for use with visiting school groups. The materials focused on the adaptations of 6 selected groups of bird species and were organized as a self-guided learning environment (workstations). The value of the materials was assessed in terms of cognitive (learning and retention) and emotional (interest, well-being, boredom, anxiety, contentedness) variables. The authors measured prior knowledge (1 week before the zoo visit), learning effect (1 week after the visit), and retention (8 to 9 weeks later). A total of 103 students (6th graders aged between 11–12 years) participated in the study, 77 receiving a treatment about adaptations in bird species and 26 receiving a treatment about reptiles which served as a control. Students had similar prior knowledge, but 1 week later students receiving the bird unit scored significantly better and this persisted into retention. Girls achieved higher scores than boys, both 1 week and 8 to 9 weeks after the visit. Surprisingly, students in the control group reported higher interest, well-being and contentedness, and lower boredom than those in the treatment group.  相似文献   
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