Neuroanatomical substrates of age-related cognitive decline.

There are many reports of relations between age and cognitive variables and of relations between age and variables representing different aspects of brain structure and a few reports of relations between brain structure variables and cognitive variables. These findings have sometimes led to inferences that the age-related brain changes cause the age-related cognitive changes. Although this conclusion may well be true, it is widely recognized that simple correlations are not sufficient to warrant causal conclusions, and other types of correlational information, such as mediation and correlations between longitudinal brain changes and longitudinal cognitive changes, also have limitations with respect to causal inferences. These issues are discussed, and the existing results on relations of regional volume, white matter hyperintensities, and diffusion tensor imaging measures of white matter integrity to age and to measures of cognitive functioning are reviewed. It is concluded that at the current time the evidence that these aspects of brain structure are neuroanatomical substrates of age-related cognitive decline is weak. The final section contains several suggestions concerning measurement and methodology that may lead to stronger conclusions in the future. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Causation mechanisms in car-to-vulnerable road user crashes: Implications for active safety systems

Vulnerable road users (VRUs), such as pedestrians and bicyclists, are often involved in crashes with passenger cars. One way to prevent these crashes is to deploy active safety systems that support the car drivers and/or VRUs. However, to develop such systems, a thorough understanding of crash causation mechanisms is required. The aim of this study is to identify crash causation mechanisms from the perspective of the VRUs, and to explore the implications of these mechanisms for the development of active safety systems. Data originate from the European project SafetyNet, where 995 crashes were in-depth investigated using the SafetyNet Accident Causation System (SNACS). To limit the scope, this study analyzed only intersection crashes involving VRUs. A total of 56 VRU crashes were aggregated. Results suggest that, while 30% of the VRUs did not see the conflict car due to visual obstructions in the traffic environment, 70% of the VRUs saw the car before the collision, but still misunderstood the traffic situation and/or made an inadequate plan of action. An important implication that follows from this is that, while detection of cars is clearly an issue that needs to be addressed, it is even more important to help the VRUs to correctly understand traffic situation (e.g., does the driver intend to slow down, and if s/he does, is it to let the VRU cross or for some other reason?). The former issue suggests a role for various cooperative active safety systems, as the obstacles are generally impenetrable with regular sensors. The latter issue is less straightforward. While various systems can be proposed, such as providing gap size estimation and reducing the car speed variability, the functional merits of each such a system need to be further investigated.     

Injury causation in the great outdoors: A systems analysis of led outdoor activity injury incidents

Despite calls for a systems approach to assessing and preventing injurious incidents within the led outdoor activity domain, applications of systems analysis frameworks to the analysis of incident data have been sparse. This article presents an analysis of 1014 led outdoor activity injury and near miss incidents whereby a systems-based risk management framework was used to classify the contributing factors involved across six levels of the led outdoor activity ‘system’. The analysis identified causal factors across all levels of the led outdoor activity system, demonstrating the framework's utility for accident analysis efforts in the led outdoor activity injury domain. In addition, issues associated with the current data collection framework that potentially limited the identification of contributing factors outside of the individuals, equipment, and environment involved were identified. In closing, the requirement for new and improved data systems to be underpinned by the systems philosophy and new models of led outdoor activity accident causation is discussed.     

黄酒蛋白质的测定及其沉淀原因探讨

蛋白质是造成黄酒沉淀的主要因素。蛋白质的测定方法有凯氏法和隆丁法。瓶装黄酒酒脚中粗蛋白含量达50.56%，其中高分子蛋白质占72.62%。控制高分子蛋白含量对防止黄酒沉淀有重要作用。     

凤滩电厂6号水轮机尾水锥管裂纹原因分析及处理

凤滩水电厂6号机组投产不到一年的时间,尾水锥管与基础环焊接处X-Y象限产生大范围的裂纹,已经严重影响到新机组的安全稳定运行。本文重点介绍凤滩6号机组尾水锥管裂纹的处理方案,并初步分析了裂纹产生的原因及预防措施,经处理该缺陷得到了有效解决。     

中低度浓香型白酒浑浊沉淀的成因及防止措施

中低度浓香型白酒浑浊沉淀严重影响产品质量和企业效益。白酒浑浊沉淀有白色片状沉淀、白色絮状沉淀、棕黄色沉淀和油状物。白色沉淀主要由香精香料添加剂、金属容器及管道、水质、过滤设备和新酒瓶等因素引起；白色絮状沉淀主要由3种高级脂肪酸乙酯，即油酸乙酯、棕榈酸乙酯、亚油酸乙酯和杂醇油的溶解条件变化而引起；棕黄色沉淀主要是由铁离子形成的棕色沉淀物质；油状物主要由白酒中的呈香物质产生。针对各浑浊沉淀物质的特点和形成机理，采取针对性的方法可有效去除浑浊沉淀物，提高酒的质量。     

水工混凝土常见渗漏的防治

就水工混凝土常见的渗漏水问题，对渗漏的原因从施工的角度进行了详细剖析，并重点介绍了相应的处理措施。     

From Covariation to Causation: A Test of the Assumption of Causal Power.

How humans infer causation from covariation has been the subject of a vigorous debate, most recently between the computational causal power account (P. W. Cheng, 1997) and associative learning theorists (e.g., K. Lober & D. R. Shanks, 2000). Whereas most researchers in the subject area agree that causal power as computed by the power PC theory offers a normative account of the inductive process. Lober and Shanks, among others, have questioned the empirical validity of the theory. This article offers a full report and additional analyses of the original study featured in Lober and Shanks's critique (M. J. Buehner & P. W. Cheng, 1997) and reports tests of Lober and Shanks's and other explanations of the pattern of causal judgments. Deviations from normativity, including the outcome-density bias, were found to be misperceptions of the input or other artifacts of the experimental procedures rather than inherent to the process of causal induction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

电抗移相相复励发电机无功不足的原因分析及处理措施

开平市在20世纪70年代所建的小水电站低压机组很大一部分是采用电抗移相相复励磁,这种励磁装置具有线路简单、可靠性高、维护工作量小、无功调节范围宽和自励恒压特性较好等优点。但当使用不正确时,会出现发电机不能发出额定无功的毛病,针对该装置几种常见的发不足无功情况加以分析。     

应重视低温制冷机油压安全讯号装置的定期维护

介绍了一起ZL2.8/194型回热式气体制冷机，因油压安全讯号装置失灵，导致制冷机工作压力不上升及相关故障的发生经过，原因分析和几点启示。