Fit and fill analysis of a newly designed femoral stem in cementless total hip arthroplasty for patients with secondary osteoarthritis

The fit and fill of the femoral canal are critical to the success of cementless femoral stems in total hip arthroplasty. It is difficult for conventional stems to provide a good fit and fill for the femora of patients with secondary osteoarthritis. Based on measurements of 100 femora of these patients, we designed two types of Fukui Medical School (FMS) stems with a proximal lateral flare that differed in the medial radius. We compared the fit and fill of the FMS stems with those of four conventional stems, using computer simulation. The mean proximal fit and total fit of the FMS stems were 46% and 53% respectively, a significant improvement compared with the other stems examined. The mean fill of FMS stems was 82% at the lower end of the lesser trochanter and 84% at the upper end of the isthmus, values that were significantly higher than those of the other stems. Since September 1995, we have implanted FMS stems in 15 hips with secondary osteoarthritis. Radiographic evaluations showed that the canal fill of the FMS stems was significantly greater in the proximal femur compared with other stems previously inserted at our department. A summary of this paper was presented at the 9th Symposium on Computer-Assisted Radiology; June 1995, Berlin, and at the 8th International Symposium on Technology in Arthroplasty; September 1995, Puerto Rico.     

Improved sib-pair linkage test for disease susceptibility loci

An improved sib-pair test for linkage is introduced which is superior to the previously proposed tests. The test is derived from the standard chi-squared goodness of fit statistic by restricting the alternative hypothesis to the genetically possible. Critical values are given and exact power comparisons are made with the previously proposed tests. The new test is shown to be more powerful for finite samples as well as being asymptotically uniformly most powerful. © 1993 Wiley-Liss, Inc.     

Fiber Matrix Descriptors from Permeability Data Without Requiring Membrane Thickness: Theory,Results, and Optimization

Objective: Permeability of basement membrane and all other barriers contains a term for membrane thickness (Δx). This naturally leads to development of methods for measuring Δx that are imprecise, inaccurate, expensive, subject to preparation artifact, and inattentive to variability. Although height and shape of permeability (P) vs. probe radius (α) curves are sensitive to Δx, ln(P) or ln(P/free diffusivity or D_o) curves have shapes independent of Δx. It should, thus, be possible using such characteristics to determine fiber radius (r_f) and void volume ratio (ε) without Δx. We developed such a method to derive membrane structure by the standard model of Ogston and present its experimental evaluation. Methods: Basement membranes were self-assembled using 1: 1 Matrigel: 0.01 M Tris/150 mM NaCl/1.0 mM CaCl₂ buffer on 0.4-μ polycarbonate supports with transport measured in diffusion chambers using FITC-labeled hydroxyethyl starch probes from 25 to 102 Å in radius. Sampling was at 0.5 hr and then for each hour up to 5. Other membranes were measured 7 days after formation. Results: The best fit of the new technique occurred at 3 hr with R² = 0.949 ± 0.003 SEM, r_f = 36.8 ± 2.4 Å, and ε = 0.87 ± 0.02. Membranes studied for 7 days showed more variability but essentially the same characteristics. Conclusions: Membrane thickness is not necessary to reduce permeability of basement membrane to structure, and optimum sampling time is 3 hr.     

Measurement of axial edge lift of rigid corneal lenses*

A simple but reliable method was used to measure the axial edge lift at the total diameter over a range of back optic zone radii of several proprietary designs of rigid gas-permeable corneal lens. One of these was found to have a constant axial edge lift construction.     

锤造全冠的适合性实验研究（三种缩颈方法的比较）

用实验方法比较三种常用的缩颈方法及评价锤造全冠的边缘适合性。结果表明各组边缘间隙均大于０．１８０ｍｍ，说明锤造全冠边缘适合性较差，临床检查难以确定其间隙大小。各组近胎面轴壁间隙较小，这与冠成形时此处受力较大，冠周径变小有关，提示临氏上应避免用力和反复锤击此处。各组胎面间隙均大于０．１３０ｍｍ，表明面升高，边缘浮出量较大，冠尚未完全就位。当硬铅代型与缩颈器之间未预留冠套间隙时，所得的锤造全冠适合性更差，面间隙最大（０．９４５ｍｍ）。     

适用于医学动态监测数据的稳健参数估计方法

目的 :介绍并分析适用于医学动态监测数据的稳健参数估计方法。方法 :结合分布假设和稳健统计给出了参数估计方法。首次提出了一种迭代求取形状参数稳健估计的算法。结果 :该方法对医学动态监测中某种生理量异常所占百分比值统计量的参数估计优于临床普遍采用的方法。结论 :通过对分布拟合、估计优效性和可实现性、估计稳健性等的理论分析和模拟实验表明该方法是一种高效、可靠的稳健参数估计方法     

A critical approach to gamma variate fit of radionuclide-angiography pulmonary histograms

Radionuclide-angiography (RNA_ left-to-right intracardiac-shunt quantification algorithms, based on the part-by-part fit technique and the use of a so-called gamma variate model function (GVF), were tested via simulation analysis using data obtained from normal subjects. A good bolus of radioindicator was obtained by administering it directly into the vena subclavia. Normal subjects were defined as those having pulmonary histograms (PH) with no visible distortion caused by a shunt. Pure, non-superimposed data on the downslope of the PH curves, which are lost in presence of a shunt, proved to be appropriate reference values for testing the accuracy of results of standard shunt quantification algorithms. A generalized four-parameter GVF was introduced in order to extend the flexibility of the model function. The use of the three-parametric GVF to reconstruct the downslope of the PH curve out of the upslope data proved to be inadequate. This reveals an evident source of error in algorithms that calculate the shunt contribution by fitting GVF parameters to so-called difference-curve data. It is concluded that the inherent restricted statistical weight of RNA data prevents accurate results being obtained from standard RNA-shunt-assessment algorithms.     

Disability-Job Fit Stereotypes and the Evaluation of Persons with Disabilities at Work

The present paper describes a laboratory experiment in which raters evaluated the videotaped performance of ratees who did or did not have a disability. This disability was stereotypically either a poor fit with the job in question or not. The results indicated that actual appraisals were not influenced by stereotypes about fit or by disabilities, but that expectations concerning future performance and a number of other decisions and recommendations were influenced by this perceived fit. These results suggest that people do hold clear stereotypes about what types of disabilities lead to poor performance on a given job, and that these stereotypes are relied upon for certain personnel decisions, even in light of performance evidence that suggests that these stereotypes are invalid. Employees' disabilities may not influence supervisors' evaluations of their past performance when supervisors have clear objective performance information available. However, bias still exists in expectations for future performance and training recommendations. This bias can have severe long-term consequences on one's career within an organization. The scenario is worse when one's disability is stereotypically believed to be unsuitable to the job in question.     

组合小片胶囊释放行为的研究及其数学模型嵌合组合小片胶囊释放行为的研究及其数学模型嵌合

目的制备硝苯地平(nifedipine，NP)的速释小片、缓释小片以及不同时滞的脉冲小片和延缓小片，多途径组合实现多次脉冲释药、定位释药、定速释药及快/慢释药系统等。方法采用非线性最小二乘法模型嵌合通用程序求出各小片释药的速率方程，比较4种方案的组合释药理论速率-时间曲线与实测值的差异。结果速率方程较为准确地描述了单片释药行为，速率-时间曲线中各种组合的体外释药实测值与各模拟方程迭加形成的理论曲线较接近，表明组合释药行为是可以理论表征的，因而组合设计可控，组合效应可预估。结论通过加和速率方程可预测由各种小片不同用量、不同组合灌装于胶囊内形成的多种释药行为。     

Activation cross-sections of proton induced reactions on natural Ni up to 65 MeV

Production cross-sections of the ^natNi(p,x)^60,61Cu, ^56,57Ni, ^55,56,57,58Co nuclear reactions were measured in five experiments up to 65 MeV by using a stacked foil activation technique. The results were compared with the available literature values, predictions of the nuclear reaction model codes ALICE-IPPE, TALYS-1.4, and extracted data from the TENDL-2012 library. Spline fits were made on the basis of selected data, from which physical yields were calculated and compared with the literature values. The applicability of the ^natNi(p,x)⁵⁷Ni, ⁵⁷Co reactions for thin layer activation (TLA) was investigated. The production rate for ⁵⁵Co was compared for proton and deuteron induced reactions on Ni.