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41.
Reaching the goals moving with different speed (from 1 to 400 mm/sec), the chimpanzee revealed respective behavioural, emotional, instrumental, and cardiovascular responses. When obscuring the goal for a certain time, the chimpanzee nevertheless managed to reach it, the relations between the speed of approaching goal and behavioural or instrumental responses being preserved. Thereupon, the chimpanzee are able to reach the goal provided the latter's trace exceeds 5-10-fold the time of really acting stimulus. 相似文献
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NM Nasybullina VP Zherdev VI Gunar VM Kopelevich GS Kozlova 《Canadian Metallurgical Quarterly》1997,60(6):52-54
The authors studied the permeability of the blood-brain barrier (CEB) to two nootropics: calcium ketogomopantothenate (KRA-Ca), a GABA derivative, and and calcium salt of oxybutyrate (OB-Ca), a derivative of GOBA. It was established that both preparations penetrate the CEB easily and are found in the brain at different intervals after their administration. However, essential differences in the distribution constant of these drugs were disclosed: KPA-Ca permeated the CEB more intensively and was accumulated in larger amounts in the late-term intervals. 相似文献
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IuG Suchkov IV Khudiakov EN Emel''ianenko MI Levi VI Pushkareva IIu Suchko VIu Litvin EV Kulesh RS Zotova AL Gintsburg 《Canadian Metallurgical Quarterly》1997,17(4):42-46
The purpose of this study was to find criteria characteristic for patients in need of care and social services. The criteria should serve as a guideline for patients and staff to facilitate care planning before discharge. The sample consisted of 49 patients, born before 1925, in need of emergency inpatient treatment, admitted to medical- or orthopaedic wards. Data of the patient's self care needs were collected by interviews, assessment of self care status and need of treatment. The patients could be divided into three groups depending on type of discharge. Group A (n = 27) discharged home, group B (n = 7) discharged to geriatric clinic and group C (n = 15) discharged and in need of further care and social services. Criteria indicating the patients further assistance from the community were in group C (medical- and orthopaedic wards) deficit in daily living activities and locomotion. Group B had an increased need of support from the physiotherapist and the occupational therapist, in locomotion as well as daily living activities The physician's assessment showed that the criteria behind the decision "no further medical treatment appropriate" and "ready for discharge" were not related to medical impairment but to lack of self care, need of care, rehabilitation and social services. 相似文献
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V. A. Shabashov V. V. Sagaradze A. E. Zamatovskii V. P. Pilyugin K. A. Kozlov A. V. Litvinov N. V. Kataeva 《The Physics of Metals and Metallography》2016,117(8):805-816
The method of Mössbauer spectroscopy has been used to investigate the effect of the temperature and the rate of megaplastic deformation on the processes of dissolution–precipitation of intermetallic compounds in aging austenitic alloy with a composition of Fe–36Ni–9Al. It has been established that, upon deformation in revolving Bridgman anvils, in the temperature range of cryogenic temperatures (liquid nitrogen) up to 573 K, a change occurs in the character of phase transitions from atomic disordering and the dissolution of intermetallic compounds to their additional accelerated precipitation. The factor that affects the kinetics of the processes of dissolution–precipitation of intermetallic compounds in the metallic matrix is dynamic aging. Dynamic aging is activated with an increase in the temperature and a decrease in the deformation rate. 相似文献
45.
L. G. Korshunov V. A. Shabashov A. V. Litvinov N. L. Chernenko 《The Physics of Metals and Metallography》2010,109(5):514-523
Wear resistance and structural changes have been investigated in amorphous alloys Fe64Co30Si3B3 and Fe73.5Nb3Cu1Si13.5B9 upon wear using a fixed abrasive. The structural studies have been performed by the methods of metallography, electron microscopy, and Mössbauer spectroscopy. It has been shown that the abrasive resistance of amorphous alloys is 1.6–3.1 times lower than that of high-carbon tool steels, which have a close level of hardness. The low abrasive wear resistance of amorphous alloys is caused by the deformation softening of the alloy surface in the process of wear. The major volume of the deformed surface layer of the alloys preserves the amorphous state. Its structural changes upon wear are characterized by the formation of inhomogeneities (fragments with a size of 10–50 nm) and by a decrease in the width of the strongest “halo” in the selected-area electron-diffractions patterns. In the amorphous matrix of the Fe64Co30Si3B3 alloy, a strong magnetic texture is formed and a redistribution of atoms occurs, which leads to an increase in the local shortrange order corresponding to FeB, Fe2B, Fe3B and α-Fe phases. In microvolumes of a thin (several μm) surface layer, the formation of a nanocrystalline structure (on the order of several volume %) was revealed. A tempering of the Fe73.5Cu1Nb3S13.5B9 alloy at temperatures below 500°C does not affect the hardness and wear resistance of the alloy. At 500°C, there occurs an increase in microhardness and wear resistance of the Fe73.5Cu1Nb3S13.5B9 alloy as a result of the formation in it of a nanocrystalline structure with the retention of a certain amount of the amorphous phase. The complete crystallization of the alloy at 540°C increases the brittleness of the alloy, which leads to a sharp reduction in its wear resistance. 相似文献
46.
M Feuerstein LM Burrell VI Miller A Lincoln GD Huang R Berger 《Canadian Metallurgical Quarterly》1999,35(3):232-245
Carpal tunnel syndrome (CTS) is a disorder frequently encountered by occupational health care specialists. The health care management of this disorder has involved a diverse set of clinical procedures. The present article is a review of the literature related to CTS with an emphasis on occupational-related CTS. MEDLINE, Cumulative Index to Nursing and Allied Health Literature, PsycLIT, and NIOSHTIC databases from 1985-1997 were searched for treatment outcome studies related to CTS. Treatments of interest included surgery, physical therapy, drug therapy, chiropractic treatment, biobehavioral interventions, and occupational rehabilitation. A systematic review of the effects of these interventions on symptoms, medical status, function, return to work, psychological well-being, and patient satisfaction was completed. Compared to other treatments, the majority of studies assessed the effects of surgical interventions. Endoscopic release was associated with higher levels of physical functioning and fewer days to return to work when compared to open release. Limited evidence indicated: 1) steroid injections and oral use of B6 were associated with pain reduction; 2) in comparison to splinting, range of motion exercises appeared to be associated with less pain and fewer days to return to work; 3) cognitive behavior therapy yielded reductions in pain, anxiety, and depression; and, 4) multidisciplinary occupational rehabilitation was associated with a higher percentage of chronic cases returning to work than usual care. Workers' compensation status was associated with increased time to return to work following surgery. Conclusions are preliminary due to the small number of well-controlled studies, variability in duration of symptoms and disability, and the broad range of reported outcome measures. While there are several opinions regarding effective treatment, there is very little scientific support for the range of options currently used in practice. Despite the emerging evidence of the multivariate nature of CTS, the majority of outcome studies have focused on single interventions directed at individual etiological factors or symptoms and functional limitations secondary to CTS. 相似文献
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Empirical analysis of the profitability of moderate grazing are presented based on sample dairy farms in Pennsylvania and New York. Net income per cow was higher for dairy farms that employed moderate intensive grazing than for dairy farms that employed extensive grazing. Income appeared to be adequate for family living expenses, but moderate intensive grazing could not be considered a high profit system. Detailed analyses of dairy farms that employed moderate and extensive grazing in northern Pennsylvania indicated that returns to management and owner equity were higher for pasture enterprises than for corn silage or hay enterprises. Positive dairy profits were related to lower feed costs. Milk production was lower on farms that employed moderate grazing than on farms that employed extensive grazing. Logit regression analysis characterized farms that employed moderate intensive grazing as oriented toward dairy rather than toward crop production; these farms had lower culling rates and a greater dependence on milk sales as a share of total sales. The reduced use of fertilizers and chemicals suggests that moderate grazing had environmentally sustainable features. 相似文献