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91.
It is known that nitroglycerin (GTN) can be converted to form a nitric oxide (NO) molecule which is a highly reactive and unstable free radical species. NO is known to have many beneficial effects such as relaxing blood vessels, promoting digestive activity, and regulating blood pressure. The first experiment established an additional effect of NO, that GTN can help prevent emotionally-induced stomach stress ulcers in rats. In Experiment 2, we sought to estimate the quantity of nitrogen oxides in serum produced by GTN that is administered subcutaneously to rats. The results indicated that rats administered GTN increased significantly the amount of serum NO2 and NO3, relative to values for a control group. Since amounts of NO2 and NO3 reflect amount of NO, the administration of GTN significantly increased amount of NO. An implication of this research is that chemicals such as GTN may be used in therapy with humans for the prevention of some kinds of ulcers. Furthermore, while NO is commonly recognized as a pollutant, it has a number of beneficial effects on the body, e. g., it may slow the aging process, contribute to therapy for improtency, and facilitate memory processes.  相似文献   
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The fuzzy judgement model of Ward (1979) predicts an inverse relation between the amount of stimulus information available to subjects and the magnitude of sequential dependencies on previous stimuli and responses in psychophysical scaling tasks. Ward confirmed this prediction for magnitude estimations of interdot distance for previous responses but not for previous stimuli, although the inverse relation has been repeatedly reported for both the previous stimuli and responses in absolute identification (e.g., Mori, 1989). This paper further explores this seemingly puzzling contradiction. A magnitude estimation of loudness experiment was conducted in which the amount of stimulus information available to subjects was manipulated by a modified version of informational masking (Watson, 1987). An absolute-identification-with-feedback experiment was also conducted to check the effectiveness of the informational masking in reducing the amount of stimulus information. The results of the magnitude estimation experiment show a striking similarity with those of Ward and generalize the failure of sequential dependencies on previous stimuli to vary inversely with stimulus information. An additional assumption that judgement strategies are altered under low-information conditions is necessary to explain this result.  相似文献   
93.
Two experiments were conducted so that deaf adults with mental retardation could develop their communication skills in an institution. Deaf and hearing residents were taught sign vocabulary using the following four procedures: sign language lessons in a large group, posters, review lessons, and distribution of a sign language book. Experiment 1 was a pilot study to assess the effect of a sign language lesson, and Experiment 2 was a systematic study to evaluate the 4 procedures using a multiple baseline design. Sign language use in natural settings was monitored for 10 months, starting with the first sign language lesson. Results showed that a sign language lesson was an effective way for most hearing residents to acquire expressive signs. Three out of 4 deaf residents learned expressive signs gradually during experiments. In natural settings, hearing residents were seen to use signs spontaneously with deaf residents in many different social contexts. Additional comprehensive assessment was conducted to confirm whether or not residents could understand one another's expressive signs. Seven out of 10 residents showed correct responses more than 80% of the time.  相似文献   
94.
Caucasian-, Hispanic-, and Asian-American male and female students (n?=?764) attending a California (USA) public university reported their perceptions of sexual assault. After reading a rape vignette, participants gave their impressions of the victim; estimated time needed for recovery and treatment; and recommended a sentence for the assailant. Half of the sample received information regarding state sentencing guidelines. Relative to female participants, males perceived the victim as more responsible. Caucasian-American males had stronger reservation about the victim’s judgment. Males were less inclined to assign blame than were females. Ethnicity was the only factor influencing perceptions of recovery. Ethnicity and sentencing guidelines, but not gender, impacted imprisonment decisions. Issues impeding a unified theoretical understanding of perceptions of rape victims were considered.  相似文献   
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To elucidate the temporal characteristics of information processing for motor action differing in complexity in relation to both perceptual and cognitive information processing, we investigated whether the reaction times (RTs) to a visual target would be affected by task complexity (finger lifting or manual aiming), pre-cueing (with a pre-cue or without a pre-cue), or target location (five horizontal positions). Using the right hand, seven right-handed subjects performed two tasks, finger lifting and manual aiming at a target, with or without a pre-cue. The pre-cue announced the location of the target to be presented. An ANOVA showed significant interactions between task and location and between pre-cue and location with no significant interaction between task and pre-cue, indicating that the task-location interaction does not depend on whether or not a pre-cue is given. The manual-aiming RTs were longer than the finger-lifting RTs, and the effects of the target location on the RTs differed for finger lifting and manual aiming. It can be assumed that the longer RTs of manual aiming reflect the time for information processing that is needed when preparing for the aiming action per se, which is an extra movement performed in addition to the simple initiation of finger lifting. Differential RTs (DRTs) calculated by subtracting the finger-lifting RTs from the aiming RTs were therefore examined. The DRTs significantly differed for target locations (i.e., a lateralized effect), with the DRTs for an ipsilateral target appearing to be significantly shorter than those for contralateral and central targets. The lateralized effect appearing on the DRTs may be mediated by the processing of visual-spatial information about visual targets as motor preparations are made for manual aiming.  相似文献   
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The behaviour of atom mixing and unmixing in metallic nanoparticles has been studied in situ by transmission electron microscopy, using particles in the Au2Pb-Sn system. It is confirmed that not only spontaneous mixing but also spontaneous unmixing take place in Au2Pb particles. At room temperature, spontaneous mixing of tin atoms into Au2Pb particles takes place, and this mixing induces unmixing of lead from Au2Pb, resulting in the formation of AuSn particles accompanied by lead precipitates.  相似文献   
100.

High-resolution electron microscopy is used to determine the translation order domains of gamma particles in arrangements formed during Ostwald ripening in the alloy Ni-12at.%Al. Such arrangements have been often identified with the operation of a mechanism of particle splitting in the late stages of the coarsening process, that is when the elastic strain contribution becomes predominant. It is shown that the translation order domains are not identical in such a particle array. This leads to the conclusion that particle splitting is not necessarily the mechanism responsible for the formation of such characteristic particle arrangements. Instead, particle migration can also be considered to be the responsible mechanism for the formation of such a correlated gamma-particle spatial distribution observed in Ni-based alloys.  相似文献   
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