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61.
62.
Many occupations require standing for prolonged periods, which can be a major contributor to musculoskeletal problems and cause disturbances in different parts of the body, especially the lower back and lower extremities. The aim of this study was to investigate the effect of custom‐made insoles and exercise training on the lower limb and lower back discomfort in workers on a production line at a rubber tire factory. One hundred male workers (mean age 35.96 years, work experience of 10.62 years, standing time 6.58 hr) participated in this randomized controlled trial. The men were randomly assigned to one of four groups: (a) custom‐made insole plus lower limb exercises, (b) insoles only, (c) lower limb exercises only, and (d) no intervention. Discomfort level was recorded with a visual analog scale and a body map. The data were analyzed with analysis of covariance. The results showed a significant difference in discomfort levels between groups in the lower back (p = .001), thigh (p = .001), and knee (p = .001) areas. The combined insole and exercise group had less discomfort in the lower back, thigh, and knee. In the group that used the insole only without exercises, the discomfort level in the lower back area was reduced. The results indicate that the simultaneous use of insoles and exercises might be an effective intervention to reduce discomfort in the lower limbs and lower back in workers who remain standing for prolonged periods.  相似文献   
63.
Ni-based/SBA-15 catalysts, were promoted by 3wt % of samaria (Sm2O3), Yttria (Y2O3) and Zirconia (ZrO2), by two-solvent impregnation method. The catalysts characterization was performed by N2 adsorption–desorption, X-ray Diffraction (XRD), X-ray Fluorescence (XRF), High Resolution Transmission Electron Microscopy (HRTEM), Field Emission Electron Scanning Microscopy (FESEM), Temperature Programmed Oxidation/Reduction (TPO/TPR) and NH3-Temperature Programmed Desorption (NH3-TPD) techniques. Then, evaluated by CO2/methane reforming.The CO2/methane reforming outcomes revealed that samaria-promoted catalyst showed excellent activity, stability and cock resistance, while yttria-promoted catalyst just illustrated good activity at high temperature and zirconia-promoted catalyst didn't show any modification in catalytic performance in comparison to Ni-based catalyst with no promoter. Samaria-promoted TEM and TPR analysis, indicated adding samaria improved the NiO particles interaction with SBA-15 support pores wall and NiO dispersion. The TPO analysis displayed that coke deposition in samaria-promoted sample after 12 h reaction is less than yttria-promoted during stream of 5 h. Also, it is suggested that for samaria containing catalyst, cock deposition occurred on the support. Therefore, nickel active sites were preserved for time on stream of 12 h, which is the main reason for samaria-promoted catalyst superior stability than other's.  相似文献   
64.
65.
Black mulberry and pomegranate juices were concentrated by conventional and microwave heating at different operational pressures (7.3, 12, 38.5, and 100 kPa). The effects of each heating method on the phytochemical changes (total anthocyanin content and antioxidant activity) of juices were investigated. The effect of various heating methods on the profile of the pomegranate anthocyanins were conducted using high-performance liquid chromatography–mass spectrometry (HPLC–MS). The main anthocyanins of pomegranate quantified by HPLC–MS were cyanidin, delphidin, pelargonidin, 3-glucoside, and 3, 5-diglucoside. In black mulberry juice, the final juice concentration of 42° Brix was achieved in 140, 120, and 95 min at 100, 38.5, and 7.3 kPa respectively and the final pomegranate juice concentration of 40° Brix was achieved in 140, 127, and 109 min at 100, 38.5, and 12 kPa respectively by using a rotary evaporator. Applying microwave energy decreased the required times to 115, 95, and 60 min for black mulberry juice and to 118, 95, and 75 min for pomegranate juice. Results showed that anthocyanin degradation and consequently decrease in antioxidant activity were more pronounced in rotary evaporation compared to microwave heating method.  相似文献   
66.
Water Distribution Systems (WDSs) are indispensable infrastructures for urban societies. Due to vitality of continuous supply of drinking water in urban areas, it is necessary to have a performance evaluation and monitoring system to provide the expected level of security in water distribution systems. A main weakness point of these systems is the physical break of pipes which results in high level of water loss, pollution risk and public unsatisfactory. In this study, a framework is developed to increase physical water supply security in urban areas. For this purpose, a physical vulnerability index (PVI) is developed for evaluation of physical statues of water mains. In quantifying PVI, pipe characteristics and bedding soil specifications are considered. The importance of these factors on PVI is determined using Analytical Hierarchy Process (AHP). In system performance evaluation, the pipe role in system performance is incorporated regarding pipe location in WDS, distance of pipe from reservoir and average pressure of pipe. Then, System Physical Performance Index (SPVI) is evaluated. An optimization algorithm is employed to determine ways to improve the system performance through enhancing the physical condition of the pipe in the system at a minimum cost. The genetic algorithm is employed for solving the optimization model. A global sensitivity analysis method named FAST, is used for sensitivity analysis to incorporate the correlation between different parameters in analysis. The proposed framework is applied to a case study located in Tehran metropolitan area. The results of this study show the significant value of the proposed algorithm in supporting decision makers to better choose vulnerable pipes for rehabilitation practices in order to decrease system vulnerability against physical failures.  相似文献   
67.
With the widespread use of the Internet, the popularity of group communication‐based applications has grown considerably. Since most communications over the Internet involve the traversal of insecure networks, basic security services are necessary for these collaborative applications. These security services can be facilitated if the authorized group members share a common secret. In such distributed applications, key agreement protocols are preferred to key distribution protocols. In the past two decades, there have been many proposals for key agreement protocols. Most of these protocols are not efficient and limit the size of the underlying group. In this paper, we consider the scalability problem in group key agreement protocols. We propose a novel framework based on extension of the Diffie–Hellman key exchange protocol. The efficiency of our protocol comes from the clustering of the group members, where the common session key is established collaboratively by all participants. We present the auxiliary protocols needed when the membership changes. We show that our protocol is superior in complexity in both communication and computation overheads required to generate the session key. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
68.
This paper describes a three-year study conducted among chemistry instructors (professors and teaching assistants) at a post-secondary institution. The goal was to explore the integration process of information and communication technologies (ICT) into traditional teaching. Four undergraduate chemistry courses incorporated a course website, an electronic forum, computerized visualizations, and Web-based projects, into their curriculum. The learning technologies were integrated to enhance inquiry-based learning, visualizations, and knowledge sharing. The current study investigated chemistry instructors’ perceptions toward ICT and their activities while practicing the newly introduced technologies. The findings showed that integrating new practices is a phase-dependent process that consists of promises as well as complexities. Four transition steps were found to characterize the integration of ICT-learning environments: non-active, support-dependant, partial-independant, and total-independant. Findings indicated that the transition from traditional to ICT-enhanced learning environments involves ambivalent feelings and dichotomy among instructors.  相似文献   
69.
Reviews the book, The dissociative mind by Elizabeth F. Howell (see record 2005-14945-000). In her book, The Dissociative Mind, Elizabeth Howell presents a complex and thorough overview of what she describes as a "sea change" in psychoanalytic theory. From her vantage point as both psychoanalyst and traumatologist, she demonstrates how, in the last 15-20 years, relational trauma and the resulting impact on the individual mind-namely the splits and fissures that comprise dissociation- have made their way back into psychoanalytic thinking. Howell's elaboration of the overwhelmed, traumatized mind is very useful in clients who present with problems in thinking or who have limited capacity to symbolize. However, detailed clinical material of how an analyst thinking of dissociated self states would work with such a client, what Bromberg termed the "relational bridge," would support her fundamental assertions more effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
This study deals with production of lipase in solid state fermentation by Rhizopus oryzae from sugarcane bagasse. A tray bioreactor was designed for the extracellular enzyme production. Daily, lipase production was evaluated at several incubation temperatures. Furthermore, the influence of temperature and humidity of the cabinet, depth of solid bed, particle size, initial moisture content and supplementary substrate (olive oil) as carbon source was investigated. The obtained results showed that bioreactor temperature of 45 °C, humidity of 80%, solid bed depth of 0.5 cm, particle size in the range of 0.335–1 mm, substrate initial moisture content of 80% for the top tray and 70% for the middle tray and supplementary substrate of 8% (v/w) olive oil led to maximum lipase production. Under optimum fermentation conditions after 72‐h incubation, maximum lipase activities for the top, middle and bottom trays were 215.16, 199.36 and 52.64 U gds?1, respectively.  相似文献   
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