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71.
P Boucher N Teasdale R Courtemanche C Bard M Fleury 《Canadian Metallurgical Quarterly》1995,18(5):638-645
OBJECTIVE: To examine whether sensory changes in lower limbs associated with diabetic sensory polyneuropathy compromise postural stability in different visual sensory conditions. RESEARCH DESIGN AND METHODS: The presence and severity of sensory neuropathy was evaluated with a clinical scale and measures of nerve conduction velocity in the lower limbs. Balance control was evaluated by testing subjects' postural stability (with a force platform) with vision, without vision, and during a recovery period after being without vision. RESULTS: Neuropathic patients showed larger ranges of sway, a faster sway speed, and a greater dispersion of sway than control subjects in all conditions. They also exhibited similar or less stable postural performance with vision than that of control subjects without vision. There was a strong relationship between the severity of the neuropathy and the postural stability. CONCLUSIONS: This experiment highlights that even with vision, the postural stability of neuropathic patients is impaired and may put them at higher risk of falling when performing more challenging daily tasks. 相似文献
72.
D Ingrand J Weber CA Boucher C Loveday C Robert A Hill N Cammack 《Canadian Metallurgical Quarterly》1995,9(12):1323-1329
73.
The effect of alkali halides on the crystallization of amorphous silica powders has been investigated. Normally crystallization does not occur below 1000°C, but in the presence of about 20% by weight of lithium chloride, -quartz forms within 2 h at 700°C. In the presence of sodium and potassium salts, -cristobalite forms at about 800 to 850°C. It appears that quartz is formed in the presence of the lithium salt because Li+ can enter the quartz lattice, whereas Na+ and K+ can penetrate the more expanded polymorphic form, cristobalite. It is possible that the cations are accompanied by oxide ions in all cases to maintain electrical neutrality. Limited penetration of the amorphous particles is sufficient to nucleate the new phase. Other properties of silica products treated with salts are reviewed. 相似文献
74.
75.
Pressley Michael; Mohan Lindsey; Raphael Lisa M.; Fingeret Lauren 《Canadian Metallurgical Quarterly》2007,99(2):221
The authors developed a grounded theory about how a school serving relatively advantaged children produces high reading and writing achievement compared with schools serving similar populations of students. The school's faculty is reading and writing focused, and students experience many books as they receive explicit, demanding instruction (i.e., about how to read words, comprehend, write) connected to content learning. The school offers a positive, motivating environment. In sum, many elements that potentially supported achievement were identified, including explicit teaching of skills in the context of much reading, writing, and content learning, which is consistent with balanced perspectives on reading and writing development. A major hypothesis in the grounded theory is that even with relatively advantaged populations, great efforts may be required to produce high reading and writing achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Neuroimaging has identified an overlapping network of brain regions whose activity is modulated by mood and cognition. Studies of depressed individuals have shown changes in perception, attention, memory, and executive functions. This suggests that mood has a pervasive effect on cognition. Direct evidence of the effect of sad mood on cognition is surprisingly limited, however. Published studies have generally addressed a single cognitive ability per study because the fleeting nature of laboratory-induced mood precludes extended testing, and robust findings are limited to mood effects on memory for emotional stimuli. In this study, sad mood was induced and prolonged, enabling the effects of mood to be assessed for an array of abilities, including those that share neural substrates with sad mood and those affected by depression. Sad mood affected memory for emotional words and facial emotion recognition, but not the other processes measured, with a significant nonuniformity of effect over tasks. These results are consistent with circumscribed effects of sad mood on certain emotion-related cognitive processes, but not on cognition more generally. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
H. Abele A. Boucher P. Geltenbort M. Klein U. Schmidt C. Stellmach 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2000,440(3):760-763
The well-known technique of optical pumping can be used to polarize a neutron beam in a transient way. In our experiment we demonstrate that an unpolarized beam of ultra-cold neutrons (UCN), interacting solely with a set of magnetic fields can become polarized without losing the “wrong” spin component. 相似文献
78.
Arvey Richard D.; Maxwell Scott E.; Abraham Lauren M. 《Canadian Metallurgical Quarterly》1985,70(4):695
Comparable worth principles suggest that regression line differences between male- and female-dominated jobs be examined where pay is regressed on job evaluation point values. It is demonstrated that unreliable job evaluation measures could artifactually produce regression line differences between male- and female-dominated jobs, even when no such bias exists. A. S. Goldberger's (1984) reverse regression and other procedures are examined as alternative methods of determining bias, and it is shown that linear structural relations procedures provide accurate and nonbiased estimates of wage discrimination in comparable worth analyses. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Reilly-Harrington Noreen A.; Alloy Lauren B.; Fresco David M.; Whitehouse Wayne G. 《Canadian Metallurgical Quarterly》1999,108(4):567
This study examined the interaction of cognitive style (as assessed self-report and information-processing battery) and stressful life events in predicting the clinician-rated depressive and manic symptomatology of participants with Research Diagnostic Criteria lifetime diagnoses of bipolar disorder (n?=?49), unipolar depression (n?=?97), or no lifetime diagnosis (n?=?23). Bipolar and unipolar participants' attributional styles, dysfunctional attitudes, and negative self-referent information processing as assessed at Time 1 interacted significantly with the number of negative life events that occurred between Times 1 and 2 to predict increases in depressive symptoms from Time 1 to Time 2. Within the bipolar group, participants' Time 1 attributional styles and dysfunctional attitudes interacted significantly, and their self-referent information processing interacted marginally, with intervening life events to predict increases in manic symptoms from Time 1 to Time 2. These findings provide support for the applicability of cognitive vulnerability–stress theories of depression to bipolar spectrum disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Individual coping strategies and dyadic coping independently predict partner well-being and relationship functioning; however, it is unclear whether the coping processes are inter-related and whether they uniquely contribute to romantic relationship functioning. One hundred heterosexual dating couples rated the individual coping strategy of negative mood regulation as well as positive and negative dyadic coping. Relationship functioning was assessed via partners' reports of relationship satisfaction and observers' ratings of negative interaction in conflict. Actor-Partner Interdependence Models (APIMs; Cook & Kenny, 2005; Kashy & Kenny, 2000) revealed associations between individual coping and dyadic coping in the predicted directions. APIMs also indicated the unique contributions of positive and negative dyadic coping to relationship functioning, above and beyond contributions of individual coping strategies. Implications of dyadic coping as a target of efforts to prevent or treat partner and/or relational distress are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献