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101.
102.
Price Richard A.; Vandenberg Steven G.; Iyer Hariharan; Williams James S. 《Canadian Metallurgical Quarterly》1982,43(2):328
Applied a random effects linear model to personality data (e.g., the Eysenck Personality Questionnaire and the Comrey Personality Scales) gathered from 138 adult Swedish twins and their families. The multiple relationships surrounding the twins allowed for the estimation of variance fractions due to several genetic and environmental factors. A striking pattern of similarity among personality traits emerged. All variables were characterized by having near-zero additive genetic, small–moderate nonadditive genetic, negligible prenatal, small postnatal familial, and quite large postnatal extrafamilial effects. Personality traits were influenced primarily by the environment, especially those outside the home. Genetic influences were confounded by cultural factors. It is suggested that temporal instability, genetic epistasis, or both could be underlying factors that unify the results for personality variables. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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R. Thangaraj S. B. Gadgil B. K. Gupta J. Vaidhyanathan Iyer O. P. A. Agnihotri 《国际能源研究杂志》1982,6(2):169-173
High absorptance and low thermal emittance selective surfaces have been formed by evaporating lead sulphide onto Al evaporated Al substrates. The dependence of selectivity, α/?, on thickness has been studied. The maximum selectivity was obtained for PbS thickness of 400 Å. The emissivity is found to increase with temperature. The coatings are stable up to a temperature of 240°C in air. Long term ultraviolet irradiation causes the photo-oxidation of PbS to PbSO4 which results in the increase of emittance and a decrease in absorptance. When cycled between 0°C and 200°C, the coatings do not show any signs of degradation. 相似文献
105.
Annapureddy V.S. Marathe D.V. Ramya T.R. Bhashyam S. 《Communications, IEEE Transactions on》2009,57(2):319-326
We investigate the effect of feedback delay on the outage probability of multiple-input single-output (MISO) fading channels. Channel state information at the transmitter (CSIT) is a delayed version of the channel state information available at the receiver (CSIR). We consider two cases of CSIR: (a) perfect CSIR and (b) CSI estimated at the receiver using training symbols. With perfect CSIR, under a short-term power constraint, we determine: (a) the outage probability for beamforming with imperfect CSIT (BF-IC) analytically, and (b) the optimal spatial power allocation (OSPA) scheme that minimizes outage numerically. Results show that, for delayed CSIT, BF-IC is close to optimal for low SNR and uniform spatial power allocation (USPA) is close to optimal at high SNR. Similarly, under a longterm power constraint, we show that BF-IC is better for low SNR and USPA is better at high SNR. With imperfect CSIR, we obtain an upper bound on the outage probability with USPA and BF-IC. Results show that the loss in performance due to imperfection in CSIR is not significant, if the training power is chosen appropriately. 相似文献
106.
Memory module manufacturers face an ongoing challenge to incorporate more functionality and superior performance with each new generation of product offering. The growth in demand for memory capacity is surpassing the pace at which memory component manufacturers are able to cost-effectively produce the next generation of monolithic memory devices. This drives the need for utilizing stacked components for memory module assemblies. The complex nature of stacked chip-scale package (CSP) components coupled with a lead-free process presents unique rework challenges that needed to be studied and addressed. Reworking a CSP is complicated as the solder joints are hidden underneath the component. The process window available for the lead-free rework process is very narrow. There are number of other critical factors, which complicate and affect the repeatability of the rework process. The complications only increase with the use of stacked CSP devices. The rework of package stacked CSP components, which are complex in nature, is a daunting task. The key issues and observations with regard to the issues and challenges associated with the lead-free rework of mirror-imaged package stacked CSP components has been presented in this paper. In addition, the paper also provides a recipe for reliably reworking these packages. 相似文献
107.
Tyrone L. R. Humphries Kunyu Shen Abishek Iyer David W. Johnson Glenda C. Gobe David Nikolic-Paterson David P. Fairlie David A. Vesey 《International journal of molecular sciences》2021,22(14)
Coagulopathies common to patients with diabetes and chronic kidney disease (CKD) are not fully understood. Fibrin deposits in the kidney suggest the local presence of clotting factors including tissue factor (TF). In this study, we investigated the effect of glucose availability on the synthesis of TF by cultured human kidney tubular epithelial cells (HTECs) in response to activation of protease-activated receptor 2 (PAR2). PAR2 activation by peptide 2f-LIGRLO-NH2 (2F, 2 µM) enhanced the synthesis and secretion of active TF (~45 kDa) which was blocked by a PAR2 antagonist (I-191). Treatment with 2F also significantly increased the consumption of glucose from the cell medium and lactate secretion. Culturing HTECs in 25 mM glucose enhanced TF synthesis and secretion over 5 mM glucose, while addition of 5 mM 2-deoxyglucose (2DOG) significantly decreased TF synthesis and reduced its molecular weight (~40 kDa). Blocking glycosylation with tunicamycin also reduced 2F-induced TF synthesis while reducing its molecular weight (~36 kDa). In conclusion, PAR2-induced TF synthesis in HTECs is enhanced by culture in high concentrations of glucose and suppressed by inhibiting either PAR2 activation (I-191), glycolysis (2DOG) or glycosylation (tunicamycin). These results may help explain how elevated concentrations of glucose promote clotting abnormities in diabetic kidney disease. The application of PAR2 antagonists to treat CKD should be investigated further. 相似文献
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109.
Multidimensional Systems and Signal Processing - Filter banks are the major signal processing blocks that dissipate large amount of power in a portable digital hearing aid device. The power... 相似文献
110.
Wireless Personal Communications - Ultrasound scan plays a predominant role in assisting the health care provider for monitoring pregnancy. This methods is employed for providing insights about... 相似文献