Is there a protective role of testosterone against high-grade prostate cancer? Incidence and severity of prostate cancer in 553 patients who underwent prostate biopsy: a prospective data register

This study investigated the role of testosterone replacement therapy (TRT) in prostate safety and cancer progression. A cohort of 553 patients, 42 treated and 162 untreated hypogonadal men, and 349 eugonadal men were included. Pathological analysis of prostate biopsies examining the incidence and severity of PCa revealed that: 16.7% of treated hypogonadal men had a positive biopsy, a Gleason score of ≤6 in 71.4% and >6 in 28.6% of men, a predominant score of 3 and tumour staging of II in 85.7% men; 51.9% of untreated hypogonadal men had a positive biopsy, a Gleason score of ≤6 in 40.5% and >6 in 59.5% men, a predominant score of 3 (77.4%) and tumour staging of II (41.7%) or III (40.5%); 37.8% of eugonadal men had a positive biopsy, a Gleason score of ≤6 in 42.4% and >6 in 57.6% of men, a predominant score of 3 (82.6%) and tumour staging of II (44.7%) or III (47.7%). The incidence of positive prostate biopsies was lowest in hypogonadal men receiving TRT, with significantly lower severity of PCa in terms of staging and grading in the same group. These results suggest that TRT might have a protective effect against high-grade PCa.     

传播心理学视野下少数民族文化传播传者与受者关系新思辨

传播心理学是研究人类在信息传播活动中的心理活动规律的学科,以对媒介化信息传播过程中人的心理变化规律的掌控与把握为学科目的.本研究以传播心理学为视野,通过对传播过程中人的主体因素的本质定位,深入分析了少数民族文化传播过程中主体因素所导致的传播受阻与传播不畅.本文较为系统地梳理和审视了少数民族文化传播过程所面临的问题与困境...     

杂质的加入对乳酸钙粒径的影响

本文采用氢氧化钙与乳酸制备纳米级乳酸钙,针对氢氧化钙溶解度低于乳酸钙溶解度的特点,提出采用电导率法测定乳酸钙的过饱和度,在乳酸钙溶液接近饱和时,过滤除去未反应的氢氧化钙,抑制目标产物二次成核;并采用分光光度计确定乙醇的加入对乳酸钙纳米粉体的分散作用;采用自动电位滴定仪测定乳酸钙粉体的等电点,通过调节反应体系及洗涤液的PH远离乳酸钙粉体的等电点,可以抑制团聚。研究结果表明：向滤液中加入适量的乙醇,促进成核,抑制晶体的生长,并提高纳米粉体的分散性;乙醇的加入量为R＝1∶1（R＝V乙醇/V反应溶液）;洗涤液采用醇与氢氧化钙水溶液,所制备的纳米粒子的平均粒径达到纳米级别。     

几种遥感图像全参考质量评价算法测评

针对各种全参考客观评价算法进行了综述,并以美国德克萨斯大学的LIVE图集为对象,设计了图像质量评价算法实验测评系统并对5种图像质量评价算法进行了统计测评,实验结果表明,在5种算法中SSIM算法性能最好.     

钙的检测方法

主要介绍了钙的各种检测原理、方法、测量条件、测量范围以及所用试剂、仪器和设备 .     

读者接受因素与译文的生成

近年来接受美学的读者接受理论常被用来分析翻译过程。兹就读者接受因素在译文生成过程中所起的作用,从微观角度分析译者在处理词语、句子、段落的过程中应考虑的读者接受因素。译者应通过有意识地利用读者接受因素、关照译文读者的需求来提高译文的质量。     

Image reconstruction by adaptive bayesian classification with a locally proportional prior

This paper concerns the problem of reconstructing images from noisy data by means of Bayesian classification methods. In Klein and Press, 1992, the authors presented a method for reconstructing images called Adaptive Bayesian Classification (ABC). The ABC procedure was shown to preform very well in simulation experiments. The ABC procedure was multistaged; moreover, it involved selecting a prior at Stage n that was the posterior at Stage n - 1. In this paper the authors show that we can improve upon ABC for some problems by modifying the way we take the prior at each stage. The new proposal is to take the prior for the pixel label at each stage as proportional to the number of pixels with that label in a small neighborhood of the pixel. The ABC procedure with a locally proportional prior (ABC/LPP) tends to improve upon the ABC procedure for some problems because the prior in the iterative portion of ABC/LPP is contextual, while that in ABC in non- contextual.     

Using satellite remotely sensed data to estimate crop proportions

A NASA, USDA, and NOAA sponsored experiment called LACIE (Large Area Crop Inventory Experiment) was performed to explore the use of remotely sensed measurements from a satellite-borne sensor to estimate small grains crop acreage. This paper examines the methods used in that experiment to estimate crop proportion in individual areal segments. We discuss the estimators used in LACIE and then consider some possible modifications and extensions which can have smaller bias or variance. Some numerical examples are offered to bring out some interesting features of the estimators and in some cases to make comparisons among estimators     

A geometrically motivated parametric model in manifold estimation

The general aim of manifold estimation is reconstructing, by statistical methods, an m-dimensional compact manifold S on ^d (with m≤d) or estimating some relevant quantities related to the geometric properties of S. Focussing on the cases d=2 and d=3, with m=d or m=d?1, we will assume that the data are given by the distances to S from points randomly chosen on a band surrounding S. The aim of this paper is to show that, if S belongs to a wide class of compact sets (which we call sets with polynomial volume), the proposed statistical model leads to a relatively simple parametric formulation. In this setup, standard methodologies (method of moments, maximum likelihood) can be used to estimate some interesting geometric parameters, including curvatures and Euler characteristic. We will particularly focus on the estimation of the (d?1)-dimensional boundary measure (in Minkowski's sense) of S. It turns out, however, that the estimation problem is not straightforward since the standard estimators show a remarkably pathological behaviour: while they are consistent and asymptotically normal, their expectations are infinite. The theoretical and practical consequences of this fact are discussed in some detail.     

Biodiversity conservation implications of landscape change in an urbanizing desert of Southwestern Peru

Internal migration from the Peruvian highlands and rural areas has burdened urban areas with rapid growth. Urban expansion is threatening the desert habitat and unique vegetation communities surrounding Arequipa, one of Peru's largest cities. A 511 ha tract contiguous to the city of Arequipa has been informally designated an ecological park. Analysis of Landsat satellite imagery over a 16-year interval indicates that urban expansion is occurring in the direction of the park. The land use/land cover change analysis revealed other landscape patterns and processes, such as agricultural expansion, which are relevant to the study area. These dynamics, plus principles of landscape ecology, suggest that the park's size and shape may not be the most suitable. Conservation alternatives include the expansion of the park, the spatial connection to another nature reserve, or the design of co-management strategies. Given local historical events and the paucity of regional conservation efforts, social actors in Arequipa and in national governmental institutions will need to find practical ways to collaborate.