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1.
The objective was to characterize nerve-cuff recordings of muscle afferents to joint rotation over a large part of the physiological joint range. This information is needed to develop control strategies for functional electrical stimulation (FES) systems using muscle afferent signals for sensory feedback. Five acute rabbit experiments were performed. Tripolar cuff electrodes were implanted around the tibial and peroneal divisions of the sciatic nerve in the rabbit's left leg. The electroneurograms (ENG) were recorded during passive ankle rotation, using a ramp-and-hold profile starting at seven different joint positions (excursion=5°, velocity=10°/s, initial positions 60°, 70°, 80°, 90°, 100°, 110°, and 120°). The amplitude of the afferent activity was dependent on the initial joint position. The steady-state sensitivity of both nerve responses increased with increasing joint flexion, whereas the dynamic sensitivity increased initially but then decreased. The results indicate that recordings of the muscle afferents may provide reliable information over only a part of the physiological joint range, Despite this limitation, muscle afferent activity may be useful for motion feedback if the movement to be controlled is within a narrow joint range such as postural sway  相似文献   
2.
The paper presents the results of a study of heavily fractured calcareous rock masses outcropping in southern Italy based on both the unidimensional joint frequency (Nl) and rock quality designation (RQD) of rock cores and seismic velocity data from laboratory and down-hole tests. The in situ longitudinal wave velocities (v) were always very low and were correlated with both Nl and RQD. Between 1 and 2 km/s, small increases in velocity were associated with a considerable decrease in Nl and significant increase in RQD value. A velocity of 1.22 km/s corresponded to an RQD value of 0. The study indicated that the simple correlation proposed by the International Society for Rock Mechanics to evaluate the RQD from the unidimensional joint frequency can underestimate the results for heavily fractured rock masses, but that good correlations can be obtained between RQD and seismic velocity. Electronic Publication  相似文献   
3.
This paper is part of a project whose aim is the implementation of closed-loop control of ankle angular position during functional electrical stimulation (FES) assisted standing in paraplegic subjects using natural sensory information. In this paper, a neural fuzzy (NF) model is implemented to extract angular position information from the electroneurographic signals recorded from muscle afferents using cuff electrodes in an animal model. The NF model, named dynamic nonsingleton fuzzy logic system is a Mamdani-like fuzzy system, implemented in the framework of recurrent neural networks. The fuzzification procedure implemented was the nonsingleton technique which has been shown in previous works to be able to take into account the uncertainty in the data. The proposed algorithm was tested in different situations and was able to predict reasonably well the ankle angular trajectories especially for small excursions (as during standing) and when the stimulation sites are far from the registration sites. This suggests it may be possible to use activity from muscle afferents recorded with cuff electrodes for FES closed-loop control of ankle position during quite standing.  相似文献   
4.
This study examined whether reactance would negatively influence treatment outcome in 347 patients diagnosed with chronic forms of depression and treated at 9 sites with either Nefazodone, cognitive-behavioral analysis system of psychotherapy (CBASP), or combination therapy. Contrary to our hypotheses, reactance positively predicted treatment outcome in CBASP on 2 of 4 scales. These effects were independent of the therapeutic alliance, which also positively predicted outcome. Reactance did not predict outcome in the groups receiving medication alone or in combination with CBASP. The findings suggest that reactance may be an asset in psychotherapy among chronically depressed individuals and that reactant patients can benefit from directive psychotherapy when therapists flexibly respond to perturbations in the therapeutic relationship. Results support the importance of Aptitude × Treatment interactions in psychotherapy outcome. The direction and significance of such interactions may vary with different forms of psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
OBJECTIVE: To establish the prevalence of anticoagulant (AC) treatment, the indications, and the quality of care in primary health care. DESIGN: A cross-sectional study, in which patients on AC treatment were identified from laboratory records. The main and second indications for AC treatment and the last value of the AC-test were taken from medical records. SETTING: Eight Finnish health centres with a total population of 182091 inhabitants. RESULTS: A total of 1255 patients on AC treatment were identified, 48% of them men. The mean age was 68.9 years. The age-adjusted prevalence of AC treatment was 0.65%. The commonest main indication was atrial fibrillation (38%). It was the main or second indication in 591 patients (age-adjusted prevalence 0.30%). The next commonest main indication was deep vein thrombosis (15%), followed by pulmonary embolism (8%). A total of 274 (22%) patients were anticoagulated for cerebral circulatory disturbances. 86% of the latest prothrombin time values fell within recommended ranges. CONCLUSION: The prevalence of AC treatment in Finland seems to be high. The proportion of patients with atrial fibrillation is high, differing from the results in other countries. The monitoring of AC-treatment as the general practitioner's responsibility functions well. The quality of care is good, even in older age groups.  相似文献   
6.
This study addressed 2 questions: (a) is early-onset dysthymia associated with reports of a disturbed childhood home environment; and (b) can adverse early experiences account, at least in part, for the differing clinical presentations of dysthymia and major depression? Participants included 97 outpatients with early-onset dysthymia, 45 outpatients with episodic major depression, and 45 normal controls. The early home environment was assessed blind to diagnosis using both interview and self-report measures. Early-onset dysthymia patients reported significantly more physical and sexual abuse and poorer relationships with both parents than normal controls. In addition, patients with dysthymia reported having received significantly poorer parenting than those with episodic major depression. The results could not be accounted for by mood state effects, comorbidity with borderline and antisocial personality disorder, or comorbid major depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Transparent glass-ceramics containing ZnAl2O4:Co2+ and LiGa5O8:Co2+ crystallites have been prepared by heat treatment of glasses in the zinc aluminosilicate and lithium gallate silicate systems, respectively. Crystalline LiGa5O8 was already precipitated in an as-prepared specimen, while ZnAl2O4:Co2+ precipitated from the glass upon heat treatment. The crystallite size varies from about 5 to 20 nm with increasing heat treatment temperature for both systems, and glass-ceramics containing crystallites of less than about 10 nm are transparent. The low-temperature optical absorption and emission spectra are compared with those of single crystals, indicating that almost all of the Co2+ ions replace Zn2+ ions in the ZnAl2O4 system, while some of the Co2+ ions are incorporated into the LiGa3O8 system, although the amount of Co2+ which remains in the glass matrix is rather large in the latter system.  相似文献   
8.
New layered matrix systems designed for zero-order sustained release are presented. The devices consist of a hydrophobic middle layer and press-coated hydrophillic and/or hydrophobic barrier layer(s). The systems overcome the inherent disadvantage of non-linear release associated with diffusion-controlled matrix devices by providing additional releasing surface with time to compensate for the decreasing release rate. The in vitro release of pseudoephedrine hydrochloride as a model compound from the matrices was examined. Modulation of release from a selected matrix containing aminophylline was evaluated in a crossover study using nine beagle dogs. Preliminary in vitro/in vivo correlation was also studied. The systems described in this paper can potentially be scaled up to commercial production.  相似文献   
9.
Relationships between A. T. Beck's (1983) constructs of sociotropy/autonomy and S. J. Blatt's (see record 1976-12367-001) constructs of dependency/self-criticism and the Diagnostic and Statistical Manual of Mental Disorders-III (DSM-III) Axis II personality disorders were examined. Two measures of personality styles and a structured diagnostic interview for personality disorders were administered to 138 outpatients. Significant relationships were found between both sets of constructs and a number of personality disorders using both categorical and dimensional measures of Axis II psychopathology. These relationships were consistent with previous theory, supporting recent conceptualizations extending the range of psychopathology associated with these personality styles from depression to the personality disorders. However, the autonomy/self-criticism dimension was correlated with a broader range of personality disorder traits and diagnoses than anticipated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
There is an extremely high rate of comorbidity between Dysthymic Disorder (DD) and Major Depressive Disorder (MDD). We used family study data to test four competing models of the relationship between DD, MDD, and comorbid DD/MDD: (1) DD, MDD, and DD/MDD are all variants of a single condition; (2) MDD and DD/MDD are similar, but differ from DD; (3) DD and DD/MDD are similar, but differ from MDD; and (4) all three conditions are distinct disorders. Subjects were the first-degree relatives of 22 outpatients with DD (n = 103), 45 outpatients with MDD (n = 207), 75 outpatients with comorbid DD/MDD (n = 343), and 45 normal controls (n = 229). Best-estimate diagnoses of relatives were derived using direct and family history interviews. Relatives of patients with DD and comorbid DD/MDD exhibited significantly higher rates of DD than relatives of patients with MDD and normal probands. The rate of comorbid DD/MDD was significantly higher in the relatives of patients with DD/MDD than the relatives of normal probands. Finally, the relatives of patients with MDD and comorbid DD/MDD exhibited significantly higher rates of MDD than the relatives of normal controls. Although none of the models received unambiguous support, some were more plausible than others.  相似文献   
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