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11.
Three methods of accounting for case manager effects in tests of the efficacy of mental health services are explored. These methods include (1) treating the case manager as a fixed factor, (2) treating the case manager as a random factor, and (3) examining service effects within the case manager. They are demonstrated with data from a nationally known case management program serving individuals with serious and persistent mental illness. Specifically, 3 conceptually distinct types of services provided or brokered by case managers are identified: habilitation-rehabilitation, community support, and traditional psychiatric services. The effectiveness of each in improving clients' adjustment is then examined with multiple regression adjustment strategies and each of the 3 methods to account for case manager effects. The results provide strong support for effects attributable to case managers and some support for the efficacy of habilitation-rehabilitation and community support services beyond the effects of traditional psychiatric services. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
K.M. Chen and V. Liepa (IEEE Trans. Antennas Propag., p.576-82, September 1964) described the broadside backscatter of a thin dipole. The model is summarized by various. These work very well at all frequencies specified by those authors, except for one-physical resonance. This is the wavelength at which the antenna's total length is half a wavelength. The present author develops an alternate set of equations which are valid at resonance 相似文献
13.
Len Sherman 《电子设计技术》2004,11(3):168-170
便携式设备,如PDA、智能电话和数码相机等在使用电池供电时具有特殊的电源管理要求,效率指标固然重要,而来自尺寸和价格方面的压力也要通过不同的设计加以平衡,这些实际要求都不同于笔记本电脑等电池供电设备的设计.除了对尺寸和重量的限制外,手持产品还需解决散热问题.这些产品中不可能安装风扇,也不可能容忍较高的温度,如果这些问题得不到解决,对元件尺寸的苛刻要求很难使其达到适当的效率,同时,小型电池需要严格的电源管理,上述因素都是当电源集成在系统内部时所要考虑的. 相似文献
14.
Parameters affecting the frequencies of transformation and co-transformation with synthetic oligonucleotides in yeast. 总被引:7,自引:0,他引:7
T Yamamoto R P Moerschell L P Wakem D Ferguson F Sherman 《Yeast (Chichester, England)》1992,8(11):935-948
Factors influencing the direct transformation of the yeast Saccharomyces cerevisiae with synthetic oligonucleotides were investigated by selecting for cyc1 transformants that contained at least partially functional iso-1-cytochrome c. Approximately 3 x 10(4) transformants, constituting 0.1% of the cells, were obtained by using 1 mg of oligonucleotide in the reaction mixture. Carrier, such as heterogeneous oligonucleotides, enhanced transformation frequencies. Transformation frequencies were dramatically reduced if the oligonucleotides had a large number of mismatches or had terminally located mismatches. Transformation with oligonucleotides, but not with linearized double-strand plasmid, was efficient in a rad52- strain, suggesting that the pathway for transformation with oligonucleotides is different from that with linearized double-strand plasmid. We describe a procedure of co-transformation with two oligonucleotides, one correcting the cyc1 defect of the target allele in the host strain, and the other producing a desired amino acid alteration elsewhere in the iso-1-cytochrome c molecule; approximately 20% of the transformants obtained by co-transformation contained these desired second alterations. 相似文献
15.
Sherman J.H. Jr. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1994,41(2):287-289
Calculation shows that the linear piezoelectric effect should be readily demonstrated in X-cut quartz by Bragg reflection of X-rays, equipment for which is available in every crystal finishing room. Electrostriction should also be observable and measurable in X-cut, Y-cut and Z-cut quartz, and in other cuts having their major surfaces parallel to X-ray diffracting planes of the crystal. Mechanical compression of the quartz due to the charge on the electrodes must be considered 相似文献
16.
GW Boehm GF Sherman GD Rosen AM Galaburda VH Denenberg 《Canadian Metallurgical Quarterly》1996,6(5):696-700
BXSB mice have an approximately 40-60% incidence of neocortical ectopias in layer I of the prefrontal/motor cortex. Prior studies have found major behavioral differences between those with ectopias and their non-ectopic littermates. Some of these findings indicate that the two groups differ with respect to spatial reference and working memory. The purpose of this study was to measure reference and working memory in the same animals to test the hypothesis that the ectopics would have better reference memory but less effective working memory. The Lashley III maze has cul-de-sacs which must be eliminated, and T-choices where the animal has to decide whether to go left or right. Ectopic and non-ectopic mice were equally able to learn the maze and did not differ on cul-entry or T-choice errors. Then the maze was inverted and the animals were retested. Turning the maze upside down did not change the relative status of the blind alleys. Therefore, the reference memory knowledge from the prior week's training could be used to avoid entering the culs. However, inverting the maze caused a left-right mirror image reversal of the T-choices. Therefore, prior reference memory information would interfere with learning the new path through the maze, whereas working memory would enable the mouse to eliminate T-choice errors. Ectopic mice made less cul-entry errors and more T-choice errors than their non-ectopic littermates, as predicted. 相似文献
17.
KM Peltekian F Wong PP Liu AG Logan M Sherman LM Blendis 《Canadian Metallurgical Quarterly》1997,92(3):394-399
OBJECTIVE: Large volume paracentesis is an effective treatment for refractory ascites, but the need for routine infusion of albumin or other volume expanders remains controversial. The aim of this study was to assess the short term effects of a single 5-L paracentesis without albumin replacement on total central blood volume, systemic and renal hemodynamics, sodium homeostasis, and neurohumoral factors. PATIENTS AND METHODS: Twelve patients with biopsy-proven cirrhosis and tense, diuretic-resistant ascites were studied before and 48 h after a single 5-L paracentesis without albumin infusion. Systemic hemodynamics and total central blood volume were assessed using radionuclide angiography. Glomerular filtration rate and effective renal plasma flow were measured by inulin and para-aminohippurate clearances, respectively. Lithium clearance was used as an index of proximal tubular reabsorption of sodium. In addition, plasma concentrations of neurohumoral factors were determined. RESULTS: Total central blood volume was 2.41 +/- 0.33 L/m2 (mean +/- SEM) before and 2.34 +/- 0.18 L/m2 48 h after large volume paracentesis (p = 0.76). Similarly, no differences were detected in the cardiac index, glomerular filtration rate, effective renal plasma flow, urinary sodium excretion, hematocrit, plasma renin activity, or concentrations of plasma aldosterone, norepinephrine, or atrial natriuretic factor. CONCLUSIONS: A single large volume paracentesis without albumin replacement causes no disturbances in systemic and renal hemodynamics 48 h after the procedure. These results suggest that a single 5-L paracentesis without albumin infusion is a safe and satisfactory short term option for the management of patients with cirrhosis and tense, diuretic-resistant ascites. 相似文献
18.
A Bedekar RM Zink DH Sherman TV Line JF Van Pilsum 《Canadian Metallurgical Quarterly》1998,119(4):677-690
The amino acid sequences of the amidinotransferases and the nucleotide sequences of their genes or cDNA from four Streptomyces species (seven genes) and from the kidneys of rat, pig, human and human pancreas were compared. The overall amino acid and nucleotide sequences of the prokaryotes and eukaryotes were very similar and further, three regions were identified that were highly identical. Evidence is presented that there is virtually zero chance that the overall and high identity regions of the amino acid sequence similarities and the overall nucleotide sequence similarities between Streptomyces and mammals represent random match. Both rat and lamprey amidinotransferases were able to use inosamine phosphate, the amidine group acceptor of Streptomyces. We have concluded that the structure and function of the amidinotransferases and their genes has been highly conserved through evolution from prokaryotes to eukaryotes. The evolution has occurred with: (1) a high degree of retention of nucleotide and amino acid sequences; (2) a high degree of retention of the primitive Streptomyces guanine + cytosine (G + C) third codon position composition in certain high identity regions of the eukaryote cDNA; (3) a decrease in the specificities for the amidine group acceptors; and (4) most of the mutations silent in the regions suggested to code for active sites in the enzymes. 相似文献
19.
20.
Intergranular and transgranular chemistries of hot-pressed and sintered silicon carbides were investigated by Auger electron spectroscopy. Results indicated major differences in grain-boundary compositions between the two. Hot-pressed silicon carbide displayed a complex intergranular chemistry. Sintered silicon carbide displayed grain facets that were free of impurities and additives. The observed intergranular chemistries for both silicon carbides are discussed in terms of their relation to the processing methods. 相似文献