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1.
Microsystem Technologies - The purpose of the present enquiry is to analyse the mechanics of an incompressible fluid, with water as base fluid, through a radially symmetric plumb duct with...  相似文献   
2.
Amines such as dopamine, norepinephrine and epinephrine were analysed in the brain regions of O.mossambicus exposed to quinalphos, phenthoate and their combination for 96 hr. The three types of treatments significantly (P < 0.05) altered the amines level at various intervals in the brain regions.  相似文献   
3.
Wireless video sensor networks (WVSNs) have drawn significant attention in recent years due to the advent of low-cost miniaturized cameras, which makes it feasible to realize large-scale WVSNs for a variety of applications including security surveillance, environmental tracking, and health monitoring. However, the conventional video coding paradigms are not suitable for WVSNs due to resource constraints such as limited computation power, battery energy, and network bandwidth. In this paper, we evaluated and analyzed the performance of video codecs based on emerging video coding paradigms such as distributed video coding and distributed compressive video sensing for multihop WVSNs. The main objective of this work was to provide an insight into the computational (encoding/decoding) complexity, energy consumption, node and network lifetime, processing and memory requirements, and the quality of reconstruction of these video codecs. Based on the findings, this paper also provides some guidelines for the selection of appropriate video codecs for a given WVSN application.  相似文献   
4.
In this research work, novel polyurethanes (PUs) based on blends of curcumin/1,4-butane diol (BDO) by varying the structure of diisocyanates were prepared following step growth polymerization. Structural study of blends and various diisocyanates based PU through Fourier Transform Infrared (FTIR) spectroscopy confirmed the incorporation of curcumin into the backbone of the PU. The scanning electron microscopic (SEM) study confirmed the well dispersion of incorporated curcumin and homogeneity of surface of synthesized samples. The SEM results also indicated that surface morphology of synthesized samples much dependent on diisocynates structure. Moreover SEM images inferred that phase separation is more pronounced in aromatic diisocyanate based PU. The anti-bacterial and anti-fungal tests were performed against different strains in order to determine the biocompatibility of the curcumin based PU. The antimicrobial activity results revealed that the material having aromatic diisocyanate are more biocompatible than the aliphatic diisocyanates in the PU structure. On the whole, this work is actually a step towards the generation of novel biocompatible materials preferably useful for biomedical applications.  相似文献   
5.
Problem: Rates of walking and bicycling to school have declined sharply in recent decades, and federal and state governments have committed funds to reverse these trends. To increase rates of walking and biking to school will require understanding why many parents choose to drive their children to school and how well existing programs, like Safe Routes to School, work.

Purpose: We aimed to understand why many parents choose to drive their children even short distances to school, and what implications this has for programs to increase walking and biking to school.

Methods: We used data from a telephone survey to explore why parents drive their children to school.

Results and conclusions: We found that 75% of parents driving their children less than 2 miles to school said they did this for convenience and to save time. Nearly half of parents driving their children less than 2 miles did not allow their child to walk to school without adult supervision. Accompanying a child on a walk to school greatly increases the time the household devotes to such a trip. Few Safe Routes to School programs effectively address issues of parental convenience and time constraints.

Takeaway for practice: Safe Routes to School programs should take parental convenience and time constraints into account by providing ways children can walk to school supervised by someone other than the parent, such as by using walking school buses. To be effective, such programs need institutional support. Schools should take a multimodal approach to pupil transportation.

Research support: This research was funded by the Active Living Research program of the Robert Wood Johnson Foundation and the U.S. and California Departments of Transportation through the University of California Transportation Center.  相似文献   
6.
The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target.  相似文献   
7.
This study examined the interaction of cognitive style (as assessed self-report and information-processing battery) and stressful life events in predicting the clinician-rated depressive and manic symptomatology of participants with Research Diagnostic Criteria lifetime diagnoses of bipolar disorder (n?=?49), unipolar depression (n?=?97), or no lifetime diagnosis (n?=?23). Bipolar and unipolar participants' attributional styles, dysfunctional attitudes, and negative self-referent information processing as assessed at Time 1 interacted significantly with the number of negative life events that occurred between Times 1 and 2 to predict increases in depressive symptoms from Time 1 to Time 2. Within the bipolar group, participants' Time 1 attributional styles and dysfunctional attitudes interacted significantly, and their self-referent information processing interacted marginally, with intervening life events to predict increases in manic symptoms from Time 1 to Time 2. These findings provide support for the applicability of cognitive vulnerability–stress theories of depression to bipolar spectrum disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
This article deals with the variable MHD effects on the peristaltic flow of a non‐Newtonian fluid in the presence of heat and mass transfer. The walls of annulus are maintained at different temperatures. Continuity, momentum concentration, and energy equations are utilized in the mathematical analysis. Two types of solutions, namely, the exact and numerical, are derived. These solutions are compared and discussed. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/htj.20314  相似文献   
9.
The present investigation is concerned with the peristaltic flow of an incompressible and magnetohydrodynamic MHD third order fluid in an inclined asymmetric channel. Both thermal and velocity slip conditions have been taken into account. The channel walls are maintained at different temperatures. The governing differential systems subjected to their boundary conditions have been solved for small Deborah number. In the derived solution expressions, the long wavelength and low Reynolds number assumptions are utilized. Graphical results are presented for the pressure rise, longitudinal velocity and temperature. Comparison with the previous published work regarding viscous fluid and no-slip case is performed. Pumping and trapping phenomena are displayed graphically just to examine the various interesting aspects of the present work.  相似文献   
10.
In this study, a computational fluid dynamics (CFD) code was developed to calculate the filling pattern using volume of fluid (VOF) algorithm with donor–acceptor method for free surface simulation. This algorithm has been modified to include the pressure of the gas produced from foam degradation. For this purpose a heat transfer model and 2D foam degradation model were developed. In heat transfer model, radiation and conduction between foam and molten metal; and convection between gas and molten metal were considered. In order to evaluate the results of simulation, a bench scale casting apparatus was assembled and the casting was conducted in a transparent mold. The effect of several parameters such as coating thickness, foam density and vacuum level on the gap temperature, gap pressure and filling speed was studied with the developed software. It was found that the simulated results are in good agreement with experimental results.  相似文献   
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