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1.
Old age, adiposity, and metabolic disorders are known as risk factors for chronic tendinopathy, which is a common problem in both athletes and the general population. However, the importance of these influencing factors has not yet been well understood. This study investigated alterations in gene expression and histology of Achilles tendons of young (10 weeks) and old (100 weeks) rats bred for low (low capacity runners, LCR) and high (high capacity runners, HCR) intrinsic aerobic exercise capacity. In this rat model, LCR displayed a phenotype of reduced exercise capacity, higher body weight, and metabolic dysfunctions compared to HCR. We hypothesized that the risk factors for tendinopathy in old LCR could lead to more pronounced impairments in Achilles tendon tissue. In quantitative real-time PCR (qPCR), age-related downregulation of tenocyte markers e.g., tenomodulin, genes related to matrix modeling and remodeling (e.g., collagens, elastin, biglycan, fibronectin, tenascin C) as well as transforming growth factor beta 3 (Tgfb3) have been detected. Inflammation marker cyclooxygenase 2 (Cox2) was downregulated in old rats, while microsomal prostaglandin E synthase 2 (Ptges2) was upregulated in old HCR and old LCR. In all groups, interleukin 6 (Il6), interleukin 1 beta (Il1b), and tumor necrosis factor alpha (Tnfa) showed no significant alteration. In histological evaluation, tendons of old rats had fewer and more elongated tenocyte nuclei than young rats. Even though a higher content of glycosaminoglycans, a sign of degeneration, was found in old HCR and LCR, no further signs of tendinopathy were detectable in tendons of old rats by histological evaluation. Low intrinsic aerobic exercise capacity and the associated phenotype did not show significant effects on gene expression and tendon histology. These findings indicate that aging seems to play a prominent role in molecular and structural alterations of Achilles tendon tissue and suggests that other risk factors associated with intrinsic aerobic exercise capacity are less influential in this rat model.  相似文献   
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Building automation systems provide the potential to optimize the energy consumption of buildings as well as to detect failures in the operation of buildings. The system comprising building form–HVAC–building automation–user is becoming more complex. Providing the occupants with control over the indoor environment is widely accepted for its positive effect on their satisfaction. This paper explores what the term ‘perceived control’ means conceptually and draws implications for its application to the design and management of buildings. Personality- and environmental-psychology emphasize the importance of personal control to humans. The adaptive model of thermal comfort, findings from post-occupancy evaluations and surveys in real buildings also indicate the importance of high levels of perceived control. These models and findings exist in parallel and have not yet been interconnected and translated into models for the built environment. A new conceptual approach to explain perceived control is proposed. Satisfaction with the indoor environment occurs not only when ‘comfort’ is provided but also immediately after a successful control action, even if homeostasis has not yet been achieved (pleasure). Giving control to occupants can result in higher levels of satisfaction.  相似文献   
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从分析影响机动车排气多变量因子间复杂关系及排气检测数据特征入手,探讨了数据挖掘技术在检测工作中的应用前景。  相似文献   
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A Fabry pérot antenna with a multilayer superstrate having nonuniform unit cells has been investigated as a receiving antenna for radio frequency (RF) energy harvesting applications. Here, the primary radiator is selected as a dual‐polarized aperture coupled microstrip antenna with a double‐layer superstrate. This antenna excites orthogonal polarizations, vertical (V) and horizontal (H) in the frequency band of 6.2 and 5.8 GHz, respectively, due to the presence of two orthogonal H‐shaped slots in its ground plane. The proposed antenna provides a gain enhancement of 9.8 and 10.1 dBi at the respective frequencies. The rectifying circuit is designed for a frequency of 5.8 GHz using a voltage doubler topology. The circuit provides a power conversion efficiency of 41% at 0 dBm input power.  相似文献   
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肖巧巧  叶锦韶  尹华  陈烁娜  彭辉  阿茹娜 《化工学报》2013,64(10):3732-3740
考察了克雷伯氏菌(Klebsiella pneumoniae)对浓度为0.1~10 mg·L-1的三苯基锡(TPhT)的生物降解,分析了在无机盐培养基和去离子水中K.pneumoniae与TPhT作用过程中,其生理特性和蛋白组的变化,以期从降解菌蛋白质组以及菌体离子代谢的角度揭示有机锡的微生物降解机理。实验结果显示K.pneumoniae能有效地将TPhT降解为二苯基锡、一苯基锡和锡。TPhT在无机盐培养基和去离子水中的降解率分别为46.7%~73.6%和25.1%~87.0%。在此过程中TPhT增加了菌体细胞膜的通透性,从而引发细胞膜的损害,刺激了细胞内离子的释放,造成部分细胞的死亡。TPhT诱导菌体表达了部分与蛋白质水解、代谢过程、蛋白质运输、能量转换、TPhT抗性和降解有关的差异蛋白。  相似文献   
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Extraphysical parameters of thermal comfort. Standards define thermal comfort as a function of physical and thermophysiological parameters. From investigations of building related symptoms it is well known that satisfaction with the indoor environment also interacts with extraphysical parameters. Thus, data of 1,497 office workers investigated in phase II of the ProKlimA study have been analysed by multiple logistic regression to find associations between thermal sensation or comfort and potential non‐environmental variables. The results show diverse effects: While thermal sensation seems almost independent from non‐environmental impacts, thermal comfort and satisfaction with the indoor temperature are significantly associated with building characteristics, demographic and job related variables. From these significant and partly strong interactions we conclude, in case of analyses and assessment of complaints about thermal discomfort relevant non environmental impact factors should be considered.  相似文献   
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The angiotensin receptor/neprilysin inhibitor Sacubitril/Valsartan (Sac/Val) has been shown to be beneficial in patients suffering from heart failure with reduced ejection fraction (HFrEF). However, the impact of Sac/Val in patients presenting with heart failure with preserved ejection fraction (HFpEF) is not yet clearly resolved. The present study aimed to reveal the influence of the drug on the functionality of the myocardium, the skeletal muscle, and the vasculature in a rat model of HFpEF. Female obese ZSF-1 rats received Sac/Val as a daily oral gavage for 12 weeks. Left ventricle (LV) function was assessed every four weeks using echocardiography. Prior to organ removal, invasive hemodynamic measurements were performed in both ventricles. Vascular function of the carotid artery and skeletal muscle function were monitored. Sac/Val treatment reduced E/é ratios, left ventricular end diastolic pressure (LVEDP) and myocardial stiffness as well as myocardial fibrosis and heart weight compared to the obese control group. Sac/Val slightly improved endothelial function in the carotid artery but had no impact on skeletal muscle function. Our results demonstrate striking effects of Sac/Val on the myocardial structure and function in a rat model of HFpEF. While vasodilation was slightly improved, functionality of the skeletal muscle remained unaffected.  相似文献   
10.
A coplanar waveguide‐fed metamaterial antenna is presented for ultra‐wideband (UWB) applications. The proposed antenna is designed with single unit‐cell composite right/left‐handed transmission line (CRLH‐TL) loaded with a split‐ring resonator (SRR). The UWB characteristic is obtained by merging the zeroth‐order resonance of CRLH‐TL with two additional resonances due to the ground plane and SRR respectively. Subsequently, a partial reactive impedance surface is embedded on the rear side of the proposed antenna to enhance the realized gain without affecting the UWB response. The overall size of the antenna is 0.241λo x 0.267λo x 0.013λo (28.8 x 32 x 1.6 mm3), where λo is the free space wavelength at 2.51 GHz. The measured results indicate –10 dB fractional bandwidth of 139.19% (2.51‐14 GHz) with realized gains of 2.3, 4.6, and 6 dBi at the resonant frequencies 4, 7.84, and 10.29 GHz respectively. The measured peak realized gain is 6.6 dBi at 10.6 GHz. The radiation efficiency is above 63.85% for the entire UWB range with a peak value of 86.84%. A fairly stable group delay with variation within 1 ns is obtained throughout the operating frequency band. A good agreement has been observed between the measured and simulated results.  相似文献   
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