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21.
Rev’d Ian StJohn Fisher Ph.D. 《Science and engineering ethics》1996,2(3):335-344
Religion, defined as ‘the idea of a state that transcends ourselves and our world and the working out of the consequences
of that idea’, may influence the ethical thinking of scientists and engineers in two ways. The first is at the level of the
individual and how personal beliefs affect the choice of research, design or development projects, relationships with other
researchers and the understandings of the consequences of research on other aspects of life. The second level is that of the
social and cultural setting in which scientists and engineers work; how society decides which research to sponsor, how to
apply the results of scientific discovery and which technology it chooses to develop and for what purposes. In neither of
these areas is religious belief a necessary condition for scientists and engineers to pursue one course of action rather than
another. The existence of religious belief within the individual and society is, though, part of the ethical framework in
which scientist and engineers work and therefore something to which attention should be paid. Religion provides a particular
perspective on what should be. Conversely science and technology provide information on the nature of the person and the universe
in which we live, which must be taken into account when theologians and religious moralists apply their ethical norms and
principles. 相似文献
22.
The present experiments examined the role of the central cholinergic system in the memory impairment induced by post-training administration of a nitric oxide synthase (NOS) inhibitor in mice. Male Swiss mice received a one-trial inhibitory avoidance training (0.8 mA, 50 Hz, 1-s footshock) followed immediately by an ip injection of the NOS inhibitor
-NG-nitroarginine methyl ester (
-NAME; 100 mg/kg). Retention (cut-off time, 300 s) was tested 48 h after training. The administration of
-NAME results in memory impairment for the inhibitory avoidance task. The effects of
-NAME (100 mg/kg, ip) on retention were reversed in a dose-related manner by the centrally acting anticholinesterase physostigmine (35, 70, or 150 μg/kg, sc) administered 30 min after the NOS inhibitor. Further,
-NAME (100 mg/kg, ip)-induced memory impairment was completely antagonized by the centrally acting muscarinic cholinergic agonist oxotremorine (OTM; 25, 50, or 100 μg/kg, sc) when given 30 min after
-NAME. The peripherally acting anticholinesterase neostigmine (150 μg/kg, sc) did not modify the memory-impairing effects of
-NAME. These findings suggest that the memory impairment following post-training administration of a NOS inhibitor is mediated, at least in part, by a reduction of the activity of central muscarinic cholinergic mechanisms and are consistent with our previous view that nitric oxide may be involved in post-training neural processes underlying the storage of newly acquired information. 相似文献
23.
Male Swiss mice were allowed to explore a novel environment, provided by an open-field activity chamber, for 10 min. The procedure was repeated twice with a 24-h interval. The difference in the exploratory activity between the first (training) and the second (testing) exposures to the chamber was taken as an index of retention of this habituation task. Posttraining intraperitoneal administration of glucose (10–300 mg/kg) enhanced retention in a dose-related manner, although only the dose of 30 mg/kg of glucose produced significant effects. Thus, the dose–response curve adopted an inverted U-shaped form. Glucose (30 mg/kg) given to untrained mice did not modify their exploratory performance when recorded 24 h later. The effects of glucose on retention were time-dependent, suggesting an action on memory storage. The memory-improving actions of glucose were prevented by the simultaneous administration of both the central acting muscarinic cholinergic antagonist atropine (0.5 mg/kg) and by the central acting nicotinic cholinergic antagonist mecamylamine (5 mg/kg). In contrast, neither methylatropine (0.5 mg/kg), a peripherally acting muscarinic receptor blocker, nor hexamethonium (5 mg/kg), a peripherally acting nicotinic receptor blocker, prevented the effects of glucose on retention. Low subeffective doses of glucose (10 mg/kg) and the central anticholinesterase physostigmine (35 μg/kg), but not neostigmine (35 μg/kg), given together, act synergistically and facilitated retention. We suggest that glucose modulates memory storage of one form of learning elicited by stimuli repeatedly presented without reinforcement, probably through an enhancement of brain acetylcholine synthesis and/or its release. 相似文献
24.
Summary The dependence of the subjective vertical (SV, the angle between a subjective vertical line and body median plane) on the gravity vertical (body tilt position, angle ) and on the optical vertical (i.e., a field of parallel lines seen as background to the line to be adjusted) was investigated. The SV was measured under dry and wet conditions at different degrees of body tilt attained in either clockwise (CW) or counterclockwise (CCW) progression.The measured difference in between field-of-lines left and right of the line is smallest at the upright position (=O°) and largest at =150°/165°. All body positions show a -difference between CW and CCW attainment (hysteresis), this too being least at upright and greatest at inverted body positions.These results, and changes of with test time, are discussed relative to the hypothesis that efficiency of the statolith organs decreases with body tilt increase, favouring increase of interference of somatoreceptors and the optical reference. 相似文献
25.
S. A. Corson E. O’L. Corson R. E. Becker B. E. Ginsburg A. Trattner R. L. Connor L. A. Lucas J. Panksepp J. P. Scott 《Integrative psychological & behavioral science》1980,15(1):5-11
A model of childhood hyperkinesis, using the Telomian-beagle hybrid dog, is described, demonstrating the interactions of genetics and separation in the development of this syndrome and in the favorable responses of some of these dogs to amphetamine. This work represents the collaboration of three laboratories, utilizing chiefly methods of inhibitory training. Inducing separation distress enhanced the resistance to inhibitory training and the favorable responses to amphetamine. 相似文献
26.
In 14 experiments, subjects had to “point to” surrounding environmental locations (targets) while imagining themselves in a particular spot facing in various directions (orientations). The spatial information was either committed to memory (cognitive maps) or directly presented on each trial in the visual or tactile modality. Reaction times (RT) indicated that orientation shifts were achieved through mental rotation in the visual task, but not in the cognitive map or tactile tasks. Further, in the latter two tasks targets were located most quickly when they were adjacent to or opposite the imagined orientation. Several explanations of this finding were tested. Various aspects of the data suggest that cognitive maps are not strictly holistic, but consist of orientation-specific representations, and—at least in part—of relational propositions specific to object pairs. 相似文献
27.
Charles W. Eriksen William P. O’hara Barbara Eriksen 《Attention, perception & psychophysics》1982,32(3):261-270
An account ofsame-different discriminations that is based upon a continuous-flow model of visual information processing (C. W. Eriksen & Schultz, 1979) and response competition and inhibition between the responses by which the subject signifies his judgment is presented. We show that a response signifyingsame will on the average be executed faster due to less priming or incipient activation of the competing response,different. In the experiment, the subjects matched letters on the basis of physical identity. The degree of priming ofdifferent responses on same trials and ofsame responses ondifferent trials was manipulated by an extraneous noise letter placed in the display. Latency for judgments onsame trials increased as the feature overlap of noise and target letters decreased. Latencies were shorter ondifferent trials when the noise letter was dissimilar to either target letter than when the noise letter was the same as one of the targets. These results were consistent with the response-competition interpretation. 相似文献
28.
29.
When head-movement parallax functioned as the sole veridical distance cue during exposure to spectacles that altered the eyes’ oculomotor adjustments, sizable adaptation was obtained. This result showed that a discrimination of the distances of 60 and 30 cm can be based on head-movement parallax. Using adaptation in demonstrating that head-movement parallax can serve as a distance cue circumvents the problem that the presence of accommodation normally presents when such a demonstration is attempted. The usual contamination of head-movement parallax with accommodation is avoided, because accommodation is altered by the spectacles and does pot function as a veridical cue along with head-movement parallax. 相似文献
30.
Kevin O’Regan 《Attention, perception & psychophysics》1979,25(6):501-509
In Experiment 1, it is shown that during reading the eye makes larger saccades near long words than near short words. The effects are reduced when the subject’s peripheral vision is diminished by the use of a moving “window” centered on the subject’s fixation point, outside of which letters are replaced by Xs. In Experiment 2, it is shown that even if linguistic predictions are kept constant, the eye tends to make longer jumps when approaching THE than when approaching a three-letter verb. This “THE-skipping” effect is weaker if THE is compared with an auxiliary (HAD, WAS, or ARE) than if it is compared with a less frequently occurring verb (ATE, RAN, MET). It follows that knowledge of the lexicon can combine with information from peripheral vision fast enough to influence saccade size from moment to moment. 相似文献