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11.
The asymptotic standard errors for the procrustes solutions are derived for orthogonal rotation, direct oblique rotation and indirect oblique rotation. The standard errors for the first two rotations are obtained using the augmented information matrices. For the indirect oblique solution, the standard errors of rotated parameters are derived from the information matrix of unrotated loadings using the chain rule for information matrices. For all three types of rotation, the standard errors of rotated parameters are presented for unstandardized and standardized manifest variables. Numerical examples show the similarity of theoretical and simulated values.  相似文献   
12.
Mainstream theories of the Stroop effect suggest that faster colour classification on congruent trials (say, the word RED printed in red colour) relative to incongruent trials (GREEN in red) is due to channel interaction. Namely, information from the irrelevant word channel perturbs processing of the print colour, causing in turn slower processing of incongruent displays. In this note, I advance a new model in which colour and word are processed in parallel and completely independent channels. The Stroop effect is then the outcome of signal redundancy in congruent displays, where both colour and word contribute to the same response. Numerical computations show that the model can produce the Stroop effect (along with high accuracy rates) for a subset of parameter values. Thus, it provides a proof of existence for a separate channel theory, and a challenge to many existing theories.  相似文献   
13.
The failure to correctly report two targets (“T1”, “T2”) that follow each other in close temporal proximity has been called the “attentional blink” (AB). The AB has, so far, mainly been studied using experimental approaches. The present studies investigated individual differences in AB performance, revealing (among further findings) a high positive correlation between the accuracies of detecting the two targets correctly (r = 0.69); and between T2∣T1 accuracy and psychometric intelligence (0.41 ≤ r ≤ 0.43) and RT variability in short-term and working memory (− 0.38 ≤ r ≤ − 0.45). Together, these results support important aspects of major theoretical accounts of the AB from an individual differences perspective and introduce intelligence and intra-subject stability as contributing factors in AB performance.  相似文献   
14.
The essential activity of a manager is decision making, which is becoming more and more complex, mainly in the multi‐criteria problems. Multi‐choice goal programming (MCGP) is considered as a robust tool in operational research to solve this type of problem. However, in real world problems, determining precise targets for the goals is a difficult task. To deal with such situation, Tabrizi introduced and used in 2012 the concept of membership functions in the MCGP model in order to model the targets fuzziness of each goal. In their model, they considered just only one type of functions (triangular form), which does not reflect adequately the decision maker's preferences that are considered as an essential element for modelling the goal's fuzziness. Their model is called Fuzzy MCGP. In this paper, new ideas are presented to reformulate MCGP model to tackle all types of functions by introducing the (decision maker's) preferences. The concept of indifference thresholds is used in the new formulation for characterizing the imprecision and the preferences associated with all types of the goals. The proposed formulation provides useful insight about the solution of a new class of problems. A numerical example is given to demonstrate the validity and strength of the new formulation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
15.
原发性胆汁性肝硬化(PBC)是一种以慢性进行性胆汁淤积为特点的自身免疫性肝病,血清中抗线粒体抗体(AMAs),尤其AMA-M2升高是该病的特异性表现.AMAs在PBC发病过程中的作用是研究重点之一.丙酮酸脱氢酶复合物(PDC)的E2亚单位(PDC-E2)是AMAs的主要抗原.诱发AMAs靶抗原暴露和打破免疫耐受的主要诱因是感染及化学因素.后者或与靶抗原交叉反应,或通过对靶抗原的化学修饰,或是使凋亡后抗原的清除发生障碍,从而促进AMAs的产生.针对PDC-E2的细胞免疫主要参与PBC的发病.AMAs在PBC发病中的作用存在争议,更多研究认为其不参与PBC的发病.  相似文献   
16.
探讨正常高值血压昼夜节律与靶器官损害的相关性。入选正常高值血压者150例,其中杓型组72例,非杓型组78例,60例正常血压者为对照组。检测尿白蛋白排泄率(UAE)、颈动脉内膜中层厚度(IMT)和左心室重量指数(LVMI)。杓型组和非杓型组UAE、IMT、LVMI高于对照组(P<0.01)。非杓型组UAE、IMT、LVMI高于杓型组(P<0.05)。正常高值血压人群已出现靶器官损害,血压昼夜节律异常与早期靶器官损害密切相关。  相似文献   
17.
The present study tested real-world racial stereotype use in the context of college athletic recruiting. Stereotype confirmation suggests that observers use stereotypes as hypotheses and interpret relevant evidence in a biased way that confirms their stereotypes. Shifting standards suggest that the evaluative standard to which we hold a target changes as a function of their group membership. We examined whether stereotype confirmation and shifting standards effects would be seen in college football coaches during recruiting. College football coaches evaluated a Black or White player on several attributes and made both zero- and non-zero-sum allocations. Results suggested that coaches used the evidence presented to develop biased subjective evaluations of the players based on race while still maintaining equivalent objective evaluations. Coaches also allocated greater overall resources to the Black recruit than the White recruit.  相似文献   
18.
Dual-task methodology often directs participants’ attention towards a gross motor skill involved in the execution of a skill, but researchers have not investigated the comparative effects of attention on fine motor skill tasks. Furthermore, there is limited information about participants’ subjective perception of workload with respect to task performance. To examine this, the current study administered the NASA-Task Load Index following a simulated shooting dual-task. The task required participants to stand 15 feet from a projector screen which depicted virtual targets and fire a modified Glock 17 handgun equipped with an infrared laser. Participants performed the primary shooting task alone (control), or were also instructed to focus their attention on a gross motor skill relevant to task execution (gross skill-focused) and a fine motor skill relevant to task execution (fine skill-focused). Results revealed that workload was significantly greater during the fine skill-focused task for both skill levels, but performance was only affected for the lesser-skilled participants. Shooting performance for the lesser-skilled participants was greater during the gross skill-focused condition compared to the fine skill-focused condition. Correlational analyses also demonstrated a significant negative relationship between shooting performance and workload during the gross skill-focused task for the higher-skilled participants. A discussion of the relationship between skill type, workload, skill level, and performance in dual-task paradigms is presented.  相似文献   
19.
探讨早期目标血糖管理对严重脓毒症患者HMGB1变化的影响.严重脓毒症患者随机分为血糖控制A(4.4mmol/L~6.1mmol/L)、B(6.2mmol/L~8.3mmol/L)、C(8.4mmol/L~10.0mmol/L)三组.给予早期目标血糖管理,入ICU后0d、1d、3d、5d、7d采血测TNF-α、HMGB1浓度.三组TNF-α、HMGB1浓度及APACHEⅡ评分均呈下降趋势,A组HMGB1浓度及APACHEⅡ评分在第7d较B、C组明显降低(P<0.05).A组28d病死率较B、C组降低(P>0.05).严重脓毒症患者在早期目标血糖管理下,显著降低HMGB1浓度,降低病死率和改善预后,HMGB1可用来评价脓毒症的严重程度及预后.  相似文献   
20.
The study was designed to investigate target acquisition in the vertical plane with emphasis on establishing strategy differences associated with acquisition triggering methods. Eight subjects were tested. Measurements consisted of target acquisition time, eye-head latency differences, velocity of gaze, eyes and head, and head amplitude. Using 3-way repeated measures analyses of variance the results show that the strategy for acquisition of predictable visual targets in vertical plane with the head unrestrained significantly depended on (a) the direction of the gaze motion with respect to the gravity vector (i.e., there is significant up-down asymmetry), (b) the angular distance of the target, and (c) the method of triggering the command to acquire the target—external versus internal. The data also show that when vertical acquisition is compared with triggering methods in the horizontal plane there is a difference in overall strategy for the acquisition of targets with the same spatial distances from straight ahead gaze when both the eyes and head are used. Among the factors contributing to the difference in strategy for vertical target acquisition are the gravitational vector, the relationship of target displacement and vestibular activitation, biomechanical and neural control asymmetries, and the difference in the vertical field of view.  相似文献   
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