防止用户退货的坏招

我父亲经常嘲笑我不认识路。是的．我可以在一个地方生活四年．却仍然找不到五里外的美发厅。     

Effect of stochastically anisotropic morphology on the mechanical behavior of microbeams

In many Micro-Electro-Mechanical-Systems (MEMS) applications such as polysilicon microstructures, the size of the basic element (grain), compared with the structure’s scale, is not negligible. In these cases, the random microstructure causes statistical dispersion of its response to load, experimentally observed by many researchers. The accompanying calculations, which generally treat the material as homogeneous and isotropic, do not model the structures properly. In this work, we analytically study the relations between morphological properties and the generalized displacements of statically determinate beams, frequently used in MEMS. The analysis includes shear deformation effects, material and structural couplings such as shear and bending deformations due to normal forces, and nonisotropic effects. The governing equations are presented in a special tensorial form, which enables finding analytical expressions for the mean and covariance matrix of the generalized deflections in terms of well defined morphological parameters and their statistics.     

Treatment of patients admitted to the hospital with congestive heart failure: specialty-related disparities in practice patterns and outcomes

OBJECTIVES: This study sought to define specialty-related differences in the care and outcome of patients admitted to the hospital with congestive heart failure (CHF). BACKGROUND: Congestive heart failure is the leading diagnosis-related group (DRG) discharge diagnosis in the United States and accounts for an estimated annual hospital cost in excess of $7 billion. The clinical impact of aggressive CHF management and the importance of the subspecialist in guiding this care have not been evaluated. METHODS: To define differences in physician practice patterns, we performed a chart review of consecutive patients admitted to a university teaching hospital with a primary DRG discharge diagnosis of CHF. We compared treatment and outcome of patients cared for by a generalist (n = 160) and those whose care was guided by a cardiologist (n = 138) during their index hospital period with CHF and over the next 6 months. RESULTS: At our institution, > 50% of patients admitted to the hospital with CHF cared for by generalists alone had minimal (New York Heart Association functional class I or II) symptoms, compared with < 15% of those cared for by a cardiologist (p < 0.01). Although generalists' patients underwent significantly fewer in-hospital diagnostic tests and had shorter lengths of stay, they had a 1.7-fold increased risk of readmission for CHF within 6 months (p < 0.05). Six-month cardiac and all-cause mortality were not significantly different between the groups. The type of physician caring for the patient and a history of diabetes, previous CHF or myocardial infarction were independent predictors of readmission for CHF. CONCLUSIONS: Involvement of a cardiologist in the care of patients admitted to the hospital with CHF is associated with increased use of diagnostic testing, longer hospital stays and improved clinical outcome. These results substantiate practice guidelines that suggest a role for cardiologists in the care of symptomatic patients with CHF.     

The Fort Bragg demonstration and evaluation.

Discusses the Fort Bragg study (L. Bickman, see record 83-31861; L. Bickman et al, 1995), the results of which call into question strongly held convictions about the ways mental health services should be structured. The study found no evidence of better clinical outcomes or reduced costs from such things as unlimited access, continuity of care, freedom from benefit limitations, availability of a full range of services, case management, and managed care. The author suggests that the negative conclusions were inevitable given the way in which the demonstration's mental health services were structured and provided. On closer examination, it is clear that the study was not really a model of managed care, there were no financial incentives to use resources or services cost effectively, and the providers were not only rewarded for doing more, but also did not appear to be changing their traditional practice patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correlation of functional independence measure (FIM) and SPECT Iofetamine (I-123) as a predictor of functional return in stroke

Murine embryonic stem (ES) cells have been a useful model system for the study of various aspects of hematopoietic differentiation. Because we had observed a sharp peak of expression of the receptor tyrosine phosphatase gamma (Ptp gamma) gene between 14 and 18 days of ES-derived embryoid body differentiation, we investigated the effect of perturbation of expression of the Ptp gamma gene on ES cell differentiation, first by analyzing the effect of Ptp gamma overexpression. The murine full-length Ptp gamma cDNA in an expression vector was transfected into ES-D3 cells and stably transfected clones were isolated. Ptp gamma was expressed as an approximately 230-kD cell surface protein, and differentiating ES clones that overexpressed Ptp gamma gave rise to a normal number of hematopoietic colonies, approximately 1 CFU per 100 cells. There was, however, a significant increase of expression of early hematopoietic markers in colonies from Ptp gamma overexpressing ES cells. To confirm that the pertubation of hematopoietic differentiation was a result of Ptp gamma overexpression, we isolated ES stem cell clones expressing Ptp gamma antisense constructs and assayed embryoid bodies for the presence of hematopoietic precursors. We observed a complete absence of methylcellulose colonies, indicating absence of hematopoietic lineages. Results of these experiments point to an essential role for Ptp gamma in hematopoietic differentiation.     

Influence of sea water solution on mortar containing calcium carbonate

Normal Portland cement mortar discs containing precipitated or ground limestone at dosages of 0, 2.5, 5 and 15% were made at water/cement ratios of 0.42 or 0.60. They were hydrated in lime water or sea water solution for periods up to 1 year. The length and modulus of elasticity changes were monitored periodically. Some mortars containing CaCO₃ exhibited more than three times the expansion of the reference in sea water. The expansions were greater in samples containing fine CaCO₃. The modulus of elasticity was especially low for samples containing precipitated CaCO₃ and exposed to sea water.     

A note on the statistical correction of halo error.

Attempts to eliminate halo error from rating scales by statistical correction have assumed halo to be a systematic error associated with a ratee–rater pair that adds performance-irrelevant variance to ratings. Furthermore, overall performance ratings have been assumed to reflect this bias. Consideration of the source of halo error, however, raises the possibility that the cognitive processes resulting in halo also mediate expectations of and interactions with employees, indirectly influencing true performance and ability via instruction, feedback, and reinforcement. If so, it would not be possible to correct for halo error using overall performance ratings. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)