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In a previous preclinical study the prototype version of a partially cemented hip stem, cement-locked uncemented (CLU) prosthesis, showed optimal primary stability and moderate stress shielding. However, numerical analysis suggested that the prototype design would induce relatively high stresses in the cement and a significant relative motion between cement and metal. The present study aimed to verify if these problems could be eliminated once the CLU design is improved. The revised design was analysed using a complete finite element model of an implanted human femur. To further strengthen the predictions of the finite element analysis, the cement damage induced by a severe load history was assessed experimentally in synthetic femurs implanted with the improved CLU stem or with a clinically successful fully cemented stem. The modifications made to the CLU stem design did not reduce its good primary stability but decreased the metal-cement relative micromotion. The same load induced stresses in the cement mantle of the improved CLU stem that were significantly lower than those predicted for the prototype design. Although the presence of modelling artefacts produced a highly localized stress peak of 13 MPa. 99 per cent of the cement volume was subjected to a principal tensile stress lower then 4 MPa. These levels of stress compare favourably with the tensile fatigue limit of the acrylic cement used in this study (9.7 MPa). The experimental results further supported these findings. The cemented stem showed a number of cracks per volume unit approximately ten times higher than the partially cemented stem under investigation.  相似文献   
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The thymus provides the physiological microenvironment critical for the development of T lymphocytes, the cells that orchestrate the adaptive immune system to generate an antigen-specific response. A diverse population of stroma cells provides surface-bound and soluble molecules that orchestrate the intrathymic maturation and selection of developing T cells. Forming an intricate 3D architecture, thymic epithelial cells (TEC) represent the most abundant and important constituent of the thymic stroma. Effective models for in and ex vivo use of adult TEC are still wanting, limiting the engineering of functional thymic organoids and the understanding of the development of a competent immune system. Here a 3D scaffold is developed based on decellularized thymic tissue capable of supporting in vitro and in vivo thymopoiesis by both fetal and adult TEC. For the first time, direct evidences of feasibility for sustained graft-resident T-cell development using adult TEC as input are provided. Moreover, the scaffold supports prolonged in vitro culture of adult TEC, with a retained expression of the master regulator Foxn1. The success of engineering a thymic scaffold that sustains adult TEC function provides unprecedented opportunities to investigate thymus development and physiology and to design and implement novel strategies for thymus replacement therapies.  相似文献   
85.
ABSTRACT

Researchers are looking to utilize nanofluids as a way to increase the efficiency in solar energy applications. Metallic particles are becoming popular because of the plasmonic characteristics allowing for more absorption. Only homogenous nanofluids for solar applications have been considered. This article proposes the use of a hybrid nanofluid containing multiple types of nanoparticles with water as the base fluid exposed to radiation. This hybrid mixture can utilize a broader wavelength spectrum and absorb more heat. Recipes for combining gold, copper, aluminum, graphite, and silicon dioxide gold nanoparticles into water are given graphically and numerically for different concentrations, diameters, and container heights.  相似文献   
86.
The evaluation of package branding is important to determine its ability to connect with consumers on an emotional level. In the past, focus groups have been the traditional method used to evaluate branding; however, focus groups can be seen as an inaccurate method of gathering data due to purely qualitative data collection. This paper presents a retail shopping experiment conducted in CUShop?, a consumer experience laboratory, to determine whether consumers prefer a public label product versus a private label product, utilizing eye tracking to analyse the decision‐making process. Results illustrated that purchase decision as well as time spent observing packaging indicates that participants preferred public branded packaging with respect to its private label competitor. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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In this paper, the performance and the feasibility of inkjet-printed dipole RFID tag antennas are experimentally studied in the implementation of identifying objects with different electromagnetic properties. To estimate the performance quality, we compare our results to those obtained using traditional etched copper dipole tag antennas. We first examine the performance characteristics, i.e. the read range and the radiation patterns, of tags in free space. Then we attach the tags directly to target objects and compare the optimum performance on target objects to that of the tag in free space. The obtained results provide information about the behaviour of inkjet-printed tag antennas on different objects. This information can be used to optimize the inkjet-printed tag antenna performance for use on objects with different characteristics.  相似文献   
89.
A sense of coherence (SOC) has been found to be a strong predictor of health outcomes and life satisfaction in older adults. This study investigated mood and immune effects of anticipated voluntary housing relocation in 30 healthy older adults and 28 age-matched controls and examined whether SOC would buffer effects of relocation on natural killer (NK) cell activity. Movers completed assessments and had blood drawn 1 month before relocation to congregate living facilities; controls were assessed concurrently. Compared with the control group, movers showed decreased positive mood and NK activity and elevated thought intrusion. Positive mood mediated the relationship of moving with NK activity, whereas SOC moderated this relationship. Low SOC movers had the poorest NK activity; that of high SOC movers was less compromised. These findings are consistent with possible salutogenic contributions of SOC and positive mood to immune function in older adults facing stressful life transitions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
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