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61.
Objective: To investigate the relationship between self-awareness of functional status and performance of Instrumental Activities of Daily Living (IADL), and self-reports of quality of life (QOL) in persons with multiple sclerosis (MS). Design: A between-groups design, using a correlational approach to examine the relationship between self-awareness of functional status, IADL and QOL. Participants: We studied 47 individuals with clinically definite MS and 26 healthy controls (HCs). Measures: The Functional Behavior Profile was completed by both participants and their informants. Participants' scores were subtracted from those of their informants', and the absolute value was used as the self-awareness/concordance score. The Executive Function Performance Test measured IADL performance; QOL was measured with the Functional Assessment of Multiple Sclerosis. Results: MS participants showed lower levels of self-awareness relative to HCs. Significant correlations were observed between performance of IADL, reports of QOL and self-awareness levels of functional status. However, reports of QOL were not significantly correlated with performance of IADL. Conclusions: The positive association between self-awareness of functional status with IADL performance and QOL reports provides support for the role of awareness in rehabilitation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Interest has grown in designing new materials for groundwater treatment via "permeable reactive barriers". In the present case, a model siliceous surface, controlled pore glass (CPG), was treated with a polycation (quaternized polyvinyl pyridine, QPVP) which immobilizes anionic/nonionic mixed micelles, in order to solubilize a variety of hydrophobic pollutants. Polymer adsorption on CPG showed atypically slow kinetics and linear adsorption isotherms, which may be a consequence of the substrate porosity. The highest toluene solubilization efficiency was achieved for the silica-polycation-immobilized micelles (SPIM) with the highest polymer loading and lowest micelle binding, a result discussed in terms of the configuration of the bound polymer and the corresponding state of the bound micelles. The ability of SPIM to treat simultaneously a wide range of pollutants and reduce their concentration in solution by 20-90% was demonstrated. Optimization of SPIM systems for remediation calls for a better understanding of both the local environment of the bound micelles and their intrinsic affinities for different hydrophobic pollutants.  相似文献   
63.
The sessile nature of plants demands the development of seed-dispersal mechanisms to establish new growing loci. Dispersal strategies of many species involve drying of the dispersal unit, which induces directed contraction and movement based on changing environmental humidity. The majority of researched hygroscopic dispersal mechanisms are based on a bilayered structure. Here, we investigate the motility of the stork''s bill (Erodium) seeds that relies on the tightening and loosening of a helical awn to propel itself across the surface into a safe germination place. We show that this movement is based on a specialized single layer consisting of a mechanically uniform tissue. A cell wall structure with cellulose microfibrils arranged in an unusually tilted helix causes each cell to spiral. These cells generate a macroscopic coil by spiralling collectively. A simple model made from a thread embedded in an isotropic foam matrix shows that this cellulose arrangement is indeed sufficient to induce the spiralling of the cells.  相似文献   
64.
We present analysis, optimization, design and characterization of an integrated passive analog phase shifter at 24 GHz in a commercially available 45 nm RF-CMOS process. The design is based on a well-known RC bridge topology, which was optimized for maximum phase shift and minimal amplitude response variation versus phase and frequency. Phase is controlled by varying DC voltage on a varactor, resulting in 60° maximum phase shift with 0.1 dB amplitude variation at 24 GHz. The size of the phase shifter circuit excluding pads and input/output buffers is 40×50 μm2.  相似文献   
65.
66.
The associations between marital discord and multiple measures of well-being (depression, anxiety, life satisfaction, and self-esteem) were evaluated in a population-based sample of 416 couples in which the husband was 65 years or older. Results indicated that greater marital discord was associated with greater depression and lower life satisfaction and self-esteem. Furthermore, the associations between marital discord and well-being remained significant when statistically controlling for the rival explanation of the Big Five personality traits. Finally, there was little evidence for gender differences in the magnitude of the associations between marital discord and well-being. Findings suggest that marital discord is an important correlate of multiple measures of well-being in older individuals and that this association is not confounded by the Big Five personality traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
A three-dimensional statistical evaluation framework for performance measurement of robotic systems has been developed. A specific experimental setup has been designed, implemented, and evaluated for different robot characteristics (velocities and target location) and for a specific task. A statistical analysis method to evaluate performance is demonstrated. Results indicate the significance of this methodology since the capabilities and performance of a particular robot depend on actual operating conditions.  相似文献   
68.
Ninety 4- to 13-year-old alleged victims of sexual abuse were interviewed by police officers using the National Institute of Child Health and Human Development (NICHD) investigative interview protocol, following which they were shown a human figure drawing and asked a series of questions. The drawing and associated questions elicited an average of 86 new forensically relevant details. They were especially productive with 4- to 7-year-olds, who provided an average of 95 additional details (27% of their total) after the drawing was introduced despite having previously "exhausted" their memories. Information elicited using the drawing may be less accurate, however, because recognition memory prompts predominated, so such drawings should only be introduced late in investigative interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
Diffusion MRI studies revealed specific morphological and physiological properties of MCF7 tumors implanted in the mammary gland of immunodeficient mice. These tumors mimic the histological and pathophysiological properties of human breast cancer in patients. The experiments were conducted by (1) applying varying diffusion gradient strengths, Gd, from 0 to 20 G/cm and a short diffusion time (td = 16 ms) in order to minimize the effect of restriction and exchange of water between the intra- and extracellular compartments, and (2) applying a strong constant gradient and diffusion times up to 96 ms, revealing water restriction and exchange. The normalized signal intensity was plotted against the diffusion weighting factor b , taking into account interaction with the imaging gradients. The curves were analyzed by applying a bi-exponential decay function assuming two exchanging water compartments, with fast and slow diffusion coefficients. The amplitudes and decay constants of the two exponents, a fast and a slow one, were related to the fraction and apparent diffusion coefficients of the extra- and intracellular water, respectively, considering contributions of restriction and exchange. During tumor progression the distribution of the diffusion parameters for the same experimental protocol varied and became less homogeneous. This was predominantly due to variations in the cellularity and increased necrosis. Upon treatment of the tumors with a new anti-estrogenic drug, tamoxifen methiodide, the changes in the diffusion parameters indicated increased cell swelling. Hence, this cytostatic response to treatment was detected before actual cell death was apparent. The potential capacity of diffusion MRI is of high clinical relevance and may help improve the noninvasive diagnosis and followup of treatment of this devastating disease.  相似文献   
70.
Experimental thermal analysis and mass spectrometric results indicate that, when heated, monomethylamine nitrate dissociates to form monomethylamine anMonomethylamine, one of the dissociation products, is a flammable gas. In dry air, at room temperature, its lower limit of flammability is 4.9%. Its auPreventing acid build-up and rust formation is important for the safe handling and transport of monomethylamine nitrate.  相似文献   
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