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51.
Gottfried Allen W.; Rose Susan A.; Bridger Wagner H. 《Canadian Metallurgical Quarterly》1978,14(3):305
To determine the effects of visual, haptic, and manipulatory experiences on visual recognition of objects' shapes, 108 6-, 9-, and 12-mo-old infants were randomly assigned to 1 of 3 stimulus familiarization conditions in which they either only looked at an object (visual), looked at and manipulated an object (visual-haptic), or looked at an object encased in a transparent box that the infant manipulated (visual-manipulatory). Visual recognition memory was assessed by the paired-comparison technique in which memory is indexed by infants' differential preferences for novel and familiar stimuli. The major findings were that (a) 12-mo-olds showed evidence of memory in all conditions, (b) younger Ss showed evidence of memory only in the visual condition, and (c) at all ages Ss' preference for novel relative to familiar stimuli was significantly greater in the visual condition than in the visual-haptic and visual-manipulatory conditions, with the latter conditions not differing significantly. It is argued that the manipulatory activity per se depressed Ss' differential preferences in the visual-haptic and visual-manipulatory conditions. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
53.
Rose Susan A.; Gottfried Allen W.; Bridger Wagner H. 《Canadian Metallurgical Quarterly》1981,17(1):90
136 1-yr-old infants were tested on tasks of visual–tactual cross-modal transfer and tactual intramodal processing. In Exp I, Ss successfully differentiated novel from familiar objects by tactual exploration after 60 sec of either visual familiarization (V–T) or 60 sec of tactual familiarization (T–T); all testing that involved tactual exploration was carried out in total darkness, using infrared videotaping. In both tasks, Ss spent significantly more time manipulating novel than familiar shapes. In the T–T task they also engaged in more manipulatory episodes and exhibited more hand-to-hand transfers with the novel shapes. Neither type of transfer was shown with shorter (30-sec) familiarization periods. The finding of successful T–T transfer with 60-sec familiarization was confirmed in Exp II using different stimuli and a modified testing procedure. In both experiments there was evidence that T–T processing surpassed V–T transfer. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
Gottfried Kremer 《化学,工程师,技术》1982,54(8):705-711
Collaboration between industry, research, technical surveillance, teaching, and jurisprudence to increase the level of technical safety . An attempt is made to localize the difficulties occurring in the dialogue between the technologist and other groups in society representing far greater numbers, to show how collaboration proceeds between the many disciplines of technology, and what problems have to be solved together with lawyers, in order to permit technology continue to serve the wellbeing of society. It is hoped that this account will also stimulate fruitful discussions. 相似文献
55.
Rose Susan A.; Gottfried Allen W.; Bridger Wagner H. 《Canadian Metallurgical Quarterly》1981,17(5):661
Investigated in 4 studies with 101 infants 25.5–32 wks of age the ability of Ss to transfer information about shape across modalities. Ss were familiarized either orally or tactually and then tested for visual recognition memory. In Exp I, Ss failed to show evidence of cross-modal transfer on any of the tasks (1 oral–visual, 2 tactual–visual). When familiarization times were increased from 30 to 60 sec in Exp II, Ss showed evidence of transfer on both tactual–visual tasks. Exp III eliminated the 5–7 sec delay that generally intervenes between the familiarization and test phase. Ss were permitted to retain the stimulus in their hand (or mouth) during the test phase while simultaneously viewing a novel stimulus and a duplicate of the familiar stimulus. This modification resulted in successful transfer on 1 of the 2 tactual–visual tasks. Ss did not show evidence of transfer on the oral–visual problem in any of these studies, despite evidence from Exp IV that they could visually discriminate the paired stimuli used in these tasks and that they showed recognition memory when familiarization and testing were both visual. Results suggest that, although cross-modal transfer of information about shape is present among 6-mo-olds, it is a less robust phenomenon than that seen in older infants. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
57.
JA Gottfried SA Mayer DC Shungu Y Chang JH Duyn 《Canadian Metallurgical Quarterly》1997,49(5):1400-1404
Delayed demyelination is a rare and poorly understood complication of hypoxic brain injury. A previous case report has suggested an association with mild-to-moderate deficiency of arylsulfatase A. We describe a 36-year-old man who recovered completely from an episode of hypoxia related to drug overdose, and 2 weeks later progressed from a confusional state to deep coma. MRI showed diffuse white matter signal changes, and brain biopsy demonstrated a noninflammatory demyelinating process. Proton magnetic resonance spectroscopy revealed elevated choline and lactate and reduced N-acetyl aspartate signal in the affected white matter, consistent with demyelination and a shift to anaerobic metabolism. Arylsulfatase A activity from peripheral leukocytes was approximately 50% of normal, consistent with a "pseudodeficiency" phenotype. These findings confirm the hypothesis that relative arylsulfatase A deficiency predisposes susceptible individuals to delayed posthypoxic leukoencephalopathy and implicates lactic acidosis in the pathogenesis of this disorder. 相似文献
58.
The seed oil of Sebastiana commersoniana (Euphorbiaceae) was separated into a triglyceride and an estolide fraction by preparative thin-layer chromatography. The
triglyceride band was characterized by spectroscopic methods, and its fatty acids have been analyzed by gas chromatography
(GC) and GC-mass spectrometry (MS) and their methyl esters. Linolenic acid was the main fatty acid (65%). The estolide band
was examined by a combination of spectroscopic and chromatographic methods (ultraviolet, infrared, nuclear magnetic resonance,
fast atom bombardment-MS, GC-MS of the fatty acids before and after silylation) and was identified as a tetraglyceride, where
on α-carbon of the glyceride backbone was esterfied with 8-hydroxy-5,6-octadienoic acid, which itself was esterfied with trans-2,cis-4-decadienoic acid. The remaining positions of the glyceride backbone were occupied by common fatty acids.
This work was presented in part at the 87th Annual Meeting of the American Oil Chemists’ Society, April 28–May 1, 1996, Indianapolis,
Indiana. 相似文献
59.
Michael Gehde Michael Giese Gottfried W. Ehrenstein 《Polymer Engineering and Science》1997,37(4):702-714
Thermoplastics reinforced with random glass mat have high strength and stiffness; the fibers dominate the mechanical behavior of these composites. The results of this investigation have shown that fibers are ineffective for reinforcing hot-tool and vibration welded butt welds. The maximum weld strengths attained with GMT are comparable to the strengths of good welds of the unfilled material. The optimum hot-tool welding parameters for the reinforced materials are different from those for the unfilled material. Unfilled polypropylene is easier to weld than unfilled polyamide. This characteristic is also true of the reinforced materials. In vibration welding, high welding pressures and high amplitudes result in lower mechanical properties. The optimum penetration depends on the fiber content of the bulk material. This penetration dependence is different from that for unfilled thermoplastic, for which the mechanical properties are independent of the penetration once a steady state has been attained. 相似文献
60.
Eberhard Borsig Agnesa Fiedlerov Lyda Rychl Milan Lazr Manfred Rtzsch Gottfried Haudel 《应用聚合物科学杂志》1989,37(2):467-478
Crosslinking of polypropylene–polyethylene (PP-PE) blends involving 10, 20, 30, 40, 50, 60, 70, 80, and 90% of PP with dicumylperoxide (DCP) or tert-butyl perbenzoate (TBPB) and in the presence of coagent pentaerythritol tetrallyl ether (PETA) was investigated at 180°C. It was found that at lower concentrations of peroxide alone (e.g., 2.5% of DCP) only PE component is crosslinked in all compositions of PP-PE blends. In the crosslinking of PP-PE 50:50 with 4% of TBPB, insoluble gel was obtained, which contained 13% PP and 87% PE. If 2% PETA was also used, the portion of PP in gel increased to 39%; the total yield of gel in PP-PE blend increased from 50 to 70%. The lower crosslinking efficiency of coagent PETA in the PP-PE blends compared with PP alone is associated with better solubility of the coagent in the PE phase in contrast to the PP phase. The coagent does not particularly raise the crosslinking efficiency of peroxide in PE, but increases it in the PP phase. A remarkable decrease in melting temperature and temperature of crystallization of both polymer components depending on peroxide concentration was found by calorimetric measurements. 相似文献