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1.
S Rana CP Sodhi S Mehta K Vaiphei R Katyal S Thakur SK Mehta 《Canadian Metallurgical Quarterly》1996,15(10):810-814
1. Weaning rats were fed ad libitum isocaloric diets containing 5% and 20% casein based proteins. 5% protein diet was protein deficient diet. Pair fed rats with the 5% protein group were maintained simultaneously on 20% protein diet but the amount restricted to the amount taken up by PEM group. 2. Glutathione, antioxidative enzymes, lipid peroxidation and histopathological studies in liver and only glutathione and antioxidative enzymes in blood were carried out. 3. Rats fed the 5% protein diet developed a severe protein energy malnutrition (PEM) whereas those on pair-fed diet developed mild to moderate PEM. 4. Glutathione related thiols superoxide dismutase, glutathione peroxidase, catalase and glutathione-Stransferase with (1 Chloro 2,4-dinitro benzene (CDNB) substrate) were decreased in liver with concomitant increase of lipid peroxidation in severe PEM. In blood glutathione, glutathione peroxidase and catalase were decreased while superoxide dismutase was increased in severe PEM group. 5. Mild to moderate PEM (pair-fed group) also resulted in similar changes in liver except glutathione peroxidase, lipid peroxidation in liver and superoxide dismutase in blood. 6. Hepatic injury was detectable only in the severe PEM group. 7. Oxidative-stress and hepatic injury occurred in severe PEM and to a lesser degree in mild to moderate PEM. 相似文献
2.
This work presents a method based on Computer Aided Design or CAD for facilitating the synthesis of Revolute–Revolute (R–R) dyads with adjustable moving pivots. The CAD-based method presented in this work ensures that all prescribed rigid-body parameters used to synthesize the R–R dyad satisfy particular kinematic requirements of an R–R dyad. Through the application of this CAD method, five of the six general R–R dyad constraint equations are satisfied and therefore not essential for the synthesis of the R–R dyad. By reducing the number of dyad design constraints from six to one, the user can synthesize R–R links with adjustable moving pivots for multi-phase motion and path generation applications. The example included demonstrates the use of the CAD method in the synthesis of an RRSS path generator with adjustable moving pivots. 相似文献
3.
Marco Domenichini Ranjana Sahai Piero Castrataro Roberto Valsecchi Claudio Tonelli Francesco Greco Paolo Dario 《Microfluidics and nanofluidics》2013,15(6):753-762
The development of multilayer soft lithography methodology has seen polydimethysiloxane (PDMS) as the preferred material for the fabrication of microfluidic devices. However, the functionality of these PDMS microfluidic chips is often limited by the poor chemical resistance of PDMS to certain solvents. Here, we propose the use of a photocurable perfluoropolyether (PFPE), specifically FOMBLIN® MD40 PFPE, as a candidate material to provide a solvent-resistant buffer layer to make the device substantially impervious to chemically induced swelling. We first carried out a systematic study of the solvent resistance properties of FOMBLIN® MD40 PFPE as compared with PDMS. The comparison presented here demonstrates the superiority of FOMBLIN® MD40 PFPE over PDMS in this regard; moreover, the results permitted to categorize solvents in four different groups depending on their swelling ratio. We then present a step-by-step recipe for a novel fabrication process that uses multilayer lithography to construct a comprehensive solvent-resistant device with fluid and control channels integrated with a valve structure and also permitting easy establishment of outside connections. 相似文献
4.
Ranjana K. Mehta Leanna M. Horton Michael J. Agnew Maury A. Nussbaum 《International Journal of Industrial Ergonomics》2011,41(6):647-652
Patient handling tasks (e.g., transportation and repositioning) are important causes of musculoskeletal disorders among healthcare workers. The purpose of this study was to evaluate, during two patient handling tasks, the physical demands resulting from alternative hospital bed design features. Twenty-four novice participants were involved in two laboratory-based studies. The effects of a steering lock and adjustable push height were evaluated during a patient transportation task using perceptual responses and measures of performance and physical demands, and the effect of a bed contour feature was determined based on patient sliding distance during repeated bed raising/lowering. Use of the steering lock reduced the number of adjustments during bed maneuvering by 28% and decreased ratings of physical demands. Use of the adjustable push height reduced shoulder moments by 30%. With the contour feature, patient sliding distance was reduced by ∼40% over 12 raise/lower cycles. These results suggest that the steering lock and adjustable push height features can reduce physical demands placed on healthcare workers during patient transportation tasks. Although patient sliding distance was reduced using the contour feature, assessing direct effects of this feature on physical demands (e.g., reduced need for workers to reposition patients) will require further investigation.
Relevance to industry
Hospital bed design features have the potential to reduce physical demands required of healthcare workers, yet there have been only limited empirical studies of these. Findings of the two current studies suggest that proactive ergonomic considerations in hospital bed design can reduce these physical demands. 相似文献5.
Manbir S. Sodhi Alessandro Agnetis Ronald G. Askin 《International Journal of Flexible Manufacturing Systems》1994,6(4):287-310
The allocation of tools to machines determines potential part routes in flexible manufacturing systems. Given production requirements and a minimum feasible set of tools, the decision of how to fill vacant slots in tool magazines to maximize routing flexibility is shown to be a minimum cost network flow problem for the cases when routing flexibility is a function of the average workload per tool aggregated over tool types, or of the number of possible routes through the system. A linear programming model is then used to plan a set of routes for each part type so as to minimize either the material handling requirement or the maximum workload on any machine. The impact of these tool addition strategies on the material handling and workload equalization is investigated and computational results presented. The advantage of the overall approach is computational simplicity at each step and the ability to react to dynamic changes.This article is based upon work supported by the National Science Foundation under Grants No. DMC 85–44993 and DDM 92–15432.This work was done by the author while visiting the SIE Department of the University of Arizona. 相似文献
6.
Aditya Telang P. Deepak Salil Joshi Prasad Deshpande Ranjana Rajendran 《Data mining and knowledge discovery》2014,28(5-6):1480-1502
The last decade has witnessed an unprecedented growth in availability of data having spatio-temporal characteristics. Given the scale and richness of such data, finding spatio-temporal patterns that demonstrate significantly different behavior from their neighbors could be of interest for various application scenarios such as—weather modeling, analyzing spread of disease outbreaks, monitoring traffic congestions, and so on. In this paper, we propose an automated approach of exploring and discovering such anomalous patterns irrespective of the underlying domain from which the data is recovered. Our approach differs significantly from traditional methods of spatial outlier detection, and employs two phases—(i) discovering homogeneous regions, and (ii) evaluating these regions as anomalies based on their statistical difference from a generalized neighborhood. We evaluate the quality of our approach and distinguish it from existing techniques via an extensive experimental evaluation. 相似文献
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In the present work, the nanocomposites based on different transition metal oxides like iron oxide (Fe2O3), zinc oxide (ZnO), silicon dioxide (SiO2), zirconium dioxide (ZrO2), and titanium dioxide (TiO2) in PVA matrix have been studied for their suitability as electromagnetic interference (EMI) shielding materials in the frequency range of 4–8 GHz (C-band) and 8–12 GHz (X-band). The nanocomposites containing 0.1, 0.5, 1.0, 5.0, and 10.0 wt% of oxides in the matrix were synthesised by solvent casting method. The EMI attenuation studies in 4–12 GHz frequency range were carried out using the Vector Network Analyzer R & S: ZVA40 method by measuring the loss due to reflection. The minimum reflectivity values for the composites containing Fe2O3, ZnO, SiO2, ZrO2, and TiO2 in PVA matrix at 10 wt% concentration level in the matrix were found to be ?38.85 dB (10.4 GHz), ?33.65 dB (10.4 GHz), ?41.90 dB (10.4 GHz), ?24.90 dB (11.0 GHz), and ?32.90 dB (9.76 GHz), respectively. Based on these results, the SiO2- and Fe2O3-based composites, which also exhibit high thermal stability and mechanical strength, are found to be low-cost and efficient EMI shielding materials. 相似文献
10.
Vinyl ester resins (VERs) are often described as a cross between unsaturated polyester resins and epoxy resins. VERs offer an upgrade to epoxy resins, and they tend to be selected when chemical and temperature resistance is required. This research was aimed at developing the synthesis of unsaturated ester resins (UERs), which are similar to VERs. UERs were synthesized by the addition of dihydrodicyclopentadienyl hydrogen maleate to the terminal epoxy groups in low‐molecular‐weight bisphenol A/epichlorohydrin epoxy resins. The effect of urethanization of UERs on the properties of the crosslinked polymer was also investigated. As crosslinking monomers, styrene and glycol dimethacrylates were used. The following properties of cured UERs were determined: the heat deflection temperature, alkali resistance, and the mechanical strength. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2627–2631, 2006 相似文献