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21.
Cardiovascular disease, as the leading cause of patient death with chronic kidney disease, could be predicted by carotid atherosclerosis. The aim of the present study was to evaluate a possible relationship between serum soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and Vitamin D levels with mean right/left carotid intima-media thickness (cIMT), in the hemodialysis (HD) patients. In this cross-sectional study, serums were obtained from 50 stable chronic HD patients and 39 healthy controls. The serum levels of sTWEAK, Vitamin D, intact parathyroid hormone (iPTH) in both groups, and cIMT were determined in HD patients by standard methods. Serum levels of sTWEAK were higher [808.8 (521.6–5032.4) pg/ml vs. 664.4 (487.4–2955.8) pg/ml (p = 0.006)] and Vitamin D levels were lower [13.4 (2.5–153) ng/ml vs. 27.8 (18.4–59.0) ng/ml (p = 0.001)] in the hemodialysis patients than in the healthy control. No important correlation was found between sTWEAK Vitamin D levels (r = 0.010/p = 0.946), and mean right(r = ?0.194/p = 0.178) and left (r = 0.061/p = 0.673) cIMT in the HD patients. Our study shows that sTWEAK levels are elevated in HD patients. This elevation has no association with the cIMT.  相似文献   
22.
This paper presents a precise solution to predict the behavior of steel fiber reinforced concrete (SFRC) under the four point bending test (FPBT). All the force components at the beam section (before and after cracking) are formulated by applying these assumptions: a realistic stress-strain model is used for concrete behavior in compression, a linear response is considered for the uncracked tension region in a concrete constitutive model, and an exponential relationship is proposed as a stress-crack opening in the crack region which requires two parameters. Then the moment capacity of the critical cracked section is calculated by using these forces and satisfying equilibrium law at the section. Parametric studies are done on the behavior of SFRC to assess the sensitivity of the solution. Finally, this solution is validated with some existing experimental data. The result shows the proposed solution is able to estimate the behavior of SFRC under FPBT.  相似文献   
23.
This paper examines three methods to measure the upper arm rotation, the main contributor to produce a fast first serve in tennis. Accepted videography techniques were compared with a novel inertial gyroscope system and marker-based technique. A network of two inertial sensors on the upper arm and the chest was used to measure upper arm rotation angle and remove body artifacts. A marker-based virtual gyroscope (MBVG) was derived from Vicon marker positions in the standard Plug-in-Gait model using a vector-based method of marker trajectories and a series of geometric transformations. The results indicate that there is a close temporal feature match for all three methods when applied to the tennis serve. This paper shows that gyroscopes as well as the MBVG can be advantageous for tennis serve assessment.  相似文献   
24.
ABSTRACT

This study developed and evaluated machine learning algorithms to predict children’s physical activity category from raw accelerometer data collected at the hip. Fifty participants (mean age = 13.9 ± 3.0 y) completed 12 activity trials that were categorized into 5 categories: sedentary (SED), light household activities and games (LHHAG), moderate-vigorous games and sports (MVGS), walking (WALK), and running (RUN). Random Forest (RF) and Logistic Regression (LR) classifiers were trained with features extracted from the vector magnitude using 10?s non-overlapping windows. Classification accuracy was evaluated using leave-one-subject-out cross validation. Overall accuracy for the RF and LR classifiers was 95.7% and 94.3%, respectively. Classification accuracy was excellent for SED (96.3% – 98.1%), LHHAG (92.3% – 95.2%), WALK (94.5% – 97.1%), RUN (99.5% – 99.6%); and MVGS (87.5% – 92.7%). The results indicate that classifiers trained on features in the raw acceleration from the hip can be used for activity recognition in young people.

Abbreviations: VM: Vector Magnitude; RF: Random Forest; LR: Logistic Regression; LOSO: Leave-One-Subject-Out  相似文献   
25.
ABSTRACT

Detection of non-wear periods is an important step in accelerometer data processing. This study evaluated five non-wear detection algorithms for wrist accelerometer data and two rules for non-wear detection when non-wear and sleep algorithms are implemented in parallel. Non-wear algorithms were based on the standard deviation (SD), the high-pass filtered acceleration, or tilt angle. Rules for differentiating sleep from non-wear consisted of an override rule in which any overlap between non-wear and sleep was deemed non-wear; and a 75% rule in which non-wear periods were deemed sleep if the duration was < 75% of the sleep period. Non-wear algorithms were evaluated in 47 children who wore an ActiGraph GT3X+ accelerometer during school hours for 5 days. Rules for differentiating sleep from non-wear were evaluated in 15 adults who wore a GeneActiv Original accelerometer continuously for 24 hours. Classification accuracy for the non-wear algorithms ranged between 0.86–0.95, with the SD of the vector magnitude providing the best performance. The override rule misclassified 37.1 minutes of sleep as non-wear, while the 75% rule resulted in no misclassification. Non-wear algorithms based on the SD of the acceleration signal can effectively detect non-wear periods, while application of the 75% rule can effectively differentiate sleep from non-wear when examined concurrently.  相似文献   
26.
The evolvable multiprocessor (EvoMP), as a novel multiprocessor system-on-chip (MPSoC) machine with evolvable task decomposition and scheduling, claims a major feature of low-cost and efficient fault tolerance. Non-centralized control and adaptive distribution of the program among the available processors are two major capabilities of this platform, which remarkably help to achieve an efficient fault tolerance scheme. This letter presents the operational as well as architectural details of this fault tolerance scheme. In this method, when a processor becomes faulty, it will be eliminated of contribution in program execution in remaining run-time. This method also utilizes dynamic rescheduling capability of the system to achieve the maximum possible efficiency after processor reduction. The results confirm the efficiency and remarkable advantages of the proposed approach over common redundancy based techniques in similar systems.  相似文献   
27.
作为高等教育网络学习中心的帕亚米·努尔大学应该采取措施来建立质量管理系统.并且改革或改变教育服务的机构.在2005~2006年帕亚米·努尔大学中心组织使用EFQM模型作了自我评估,目的是为了建立质量管理系统.为了重新评估该组织,为了通过比较连续两年的成绩来监控该组织发挥作用的效果、为了检测去年进行的第一次试验结果的不足的改进程度,我们又进行了第二次试验,题目相同,试验方法稍作更改.试验的主要目的是为了重新评估该组织通过使用EFQM模型后如何提高了自己的作用并比较这两次试验的结果.本实验除了进行文献搜索以外,还进行了实地调查.  相似文献   
28.
Drawing on sociocultural theory, and a large number of empirical studies conducted on the effectiveness of scaffolding on second or foreign language learning, the authors investigated the application of different forms of scaffolding to improve listening comprehension of the Iranian intermediate English as a foreign language (EFL) learners. To this end, 90 intermediate EFL learners were randomly assigned to 2 experimental groups and a control group. During 15 treatment sessions of listening comprehension instruction, expert peers in the first experimental group assisted their less knowledgeable peers in their listening comprehension tasks. The participants in the second experimental group were asked to assist their coequal peers while doing the listening comprehension tasks, but the participants in group 3 did not interact with each other or even their teacher and no scaffolding scheme was used when they were doing the listening comprehension tasks. One-way analysis of variance and post hoc analyses revealed that the expert peers' scaffolding was the most effective procedure for the intermediate EFL learners' listening comprehension development. Furthermore, coequal peers' scaffolding was proved to be the second effective procedure for the listening comprehension improvement. The findings underscore the relative efficacy of different forms of scaffolding procedure and the superiority of the expert peers' scaffolding over coequals' scaffolding. The qualitative analysis of the recorded data indicated that the implicit scaffolding strategies were more frequently used by the expert peers. However, the explicit scaffolding strategies were more frequently used to by the coequals. The findings of the study underscore the positive potentiality of scaffolding in its different forms for the EFL learners' listening comprehension development.  相似文献   
29.
In this paper we present an alternative approach to the direct design of 1-D recursive digital filters satisfying prescribed magnitude specifications with or without constant group delay characteristic. This method uses an iterative method to calculate the coefficients of the filter's transfer function and guarantees the stability of the designed filter using a new stability test reported by Ramachandran and Gargour. To illustrate the usefulness of the technique, examples are given.  相似文献   
30.
A number of newly developed antiepileptic drugs are currently in use, among them Lamotrigine (LTG) is more common. Despite the extensive use of this drug, it has not been possible to predict the side effects especially the hepatotoxic reactions after long-term treatment. The present study was designed to find out alterations in the activities of liver enzymes after chronic exposure of rats to different dose of LTG. Adults male (Wistar) rats were treated orally with LTG [5 mg/kg body weight or 25 mg/kg body wt.] for 60 days. After the experimental period, auto analyzer carried out liver function tests. The liver histopathology was obtained after scarifying the rats. There was a significant increase in the level of ALP, AST, ALT and bilirubin at therapeutic dose of LTG. The increase level of these enzymes and bilirubin at toxic dose were much higher and significant. However, the total protein and albumin significantly decreased at toxic dose of LTG. Elevation of liver enzymes and bilirubin after chronic exposure of rats to high dose of LTG reflects hepatocellular damage that may lead to hepatitis. It is concluded that regular liver function and drug monitoring should follow the treatment with LTG.  相似文献   
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