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The triggers of biennial bearing are thought to coincide with embryonic development in apple and occurs within the first 70 days after full bloom (DAFB). Strong evidence suggests hormonal signals are perceived by vegetative apple spur buds to induce flowering. The hormonal response is typically referred to as the floral induction (FI) phase in bud meristem development. To determine the metabolic pathways activated in FI, young trees of the biennial bearing cultivar ‘Nicoter’ and the less susceptible cultivar ‘Rosy Glow’ were forced into an alternate cropping cycle over five years and an inverse relationship of crop load and return bloom was established. Buds were collected over a four-week duration within 70 DAFB from trees that had maintained a four-year biennial bearing cycle. Metabolomics profiling was undertaken to determine the differentially expressed pathways and key signalling molecules associated with biennial bearing. Marked metabolic differences were observed in trees with high and low crop load treatments. Significant effects were detected in members of the phenylpropanoid pathway comprising hydroxycinnamates, salicylates, salicylic acid biosynthetic pathway intermediates and flavanols. This study identifies plant hormones associated with FI in apples using functional metabolomics analysis.  相似文献   
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The functionally important NF-κB1 promoter polymorphism (−94ins/delATTG) significantly shapes inflammation and impacts the outcome of sepsis. However, exploratory studies elucidating the molecular link of this genotype-dependent pattern are lacking. Accordingly, we analyzed lipopolysaccharide-stimulated peripheral blood mononuclear cells from both healthy volunteers (n = 20) and septic patients (n = 10). All individuals were genotyped for the −94ins/delATTG NF-κB1 promoter polymorphism. We found a diminished nuclear activity of the NF-κB subunit p50 in ID/DD genotypes after 48 h of lipopolysaccharide stimulation compared to II genotypes (p = 0.025). This was associated with higher TNF-α (p = 0.005) and interleukin 6 concentrations (p = 0.014) and an increased production of mitochondrial radical oxygen species in ID/DD genotypes (p = 0.001). Although ID/DD genotypes showed enhanced activation of mitochondrial biogenesis, they still had a significantly diminished cellular ATP content (p = 0.046) and lower mtDNA copy numbers (p = 0.010) compared to II genotypes. Strikingly, these findings were mirrored in peripheral blood mononuclear cells taken from septic patients. Our results emphasize the crucial aspect of considering NF-κB subunits in sepsis. We showed here that the deletion allele of the NF-κB1 (−94ins/delATTG) polymorphism was associated with the lower nuclear activity of subunit p50, which, in turn, was associated with aggravated inflammation and mitochondrial dysfunction.  相似文献   
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Vishay今天主要介绍IrDA在红外线高速数据传输的应用,这是一种无线的、应用光进行高资料量的传输。为什么要选用IrDA作为无线的数据传输呢?主要是IrDA是目前各种无线传输方式中最便宜的一种,供电电压可以做得更低,并且传输的速率远远高于其它方式的传输速率。举个实例说明,目前在PDA、手机方面应用最普遍的蓝牙技术,其传输速率最多1Mbit/s,如应用IrDA,传输速率可达1Mbytes/s。全世界范围的大公司的技术方案,都支持IrDA传输的接口。由于现在无论笔记本电脑,手机还是PDA都越做越小,如果用有线的数据传输方式,你可能很难  相似文献   
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设计工程是一个以客户为中心的行业,其中新标准由终端客户的需求驱动.当演变到为电子工程设计和制造元器件时,它就再也不是一种产品适合所有应用的模式了.这就在国际上引发了一场工程师们观念上的革命.尽管在过去功能、成本控制和效率是工程师主要的着眼点,而现在一个元器件的外表形状正获得更高的关注度.  相似文献   
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The advent of readily accessible, inexpensive Web-conferencing applications has opened the door for distance psychotherapy supervision, using video recordings of treated clients. Although relatively new, this method of supervision is advantageous given the ease of use and low cost of various Internet applications. This method allows periodic supervision from point to point around the world, with no travel costs and no long gaps between direct training contacts. Web-conferencing permits face-to-face training so that the learner and supervisor can read each other's emotional responses while reviewing case material. It allows group learning from direct supervision to complement local peer-to-peer learning methods. In this article, we describe the relevant literature on this type of learning method, the practical points in its utilization, its limitations, and its benefits. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Reports an error in Age differences in psychosocial predictors of positive and negative affect: A longitudinal investigation of young, midlife, and older adults by Tim D. Windsor and Kaarin J. Anstey (Psychology and Aging, 2010[Sep], Vol 25[3], 641-652). Contains an error in Figure 3, on page 649. The correction discusses where to find the correct data. (The following abstract of the original article appeared in record 2010-18944-009.) Research has consistently shown that despite aging-related losses, older adults have high levels of emotional well-being relative to those in young and midlife adults. We aimed to contribute to knowledge around the factors that predict emotional well-being over the life course by examining age group differences in associations of positive and negative social exchanges and mastery beliefs with positive and negative affect in a sample of 7,472 young, midlife, and older adults assessed on 2 measurement occasions, 4 years apart. Results from structural equation models indicated lower levels of negative affect with advancing age. Mastery was consistently related to higher well-being, with the strongest associations evident for young adults. Older adults reported the most frequent positive and least frequent negative social exchanges; however, associations of social relations with affect tended to be stronger among young and midlife adults relative to older adults. Results are discussed in the context of life course perspectives on goal orientations and self-regulatory processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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We present a new analysis and visualization method for studying the functional relationship between the pulse morphology of pressure signals and time or signal metrics such as heart rate, pulse pressure, and means of pressure signals, such as arterial blood pressure and central venous pressure. The pulse morphology is known to contain potentially useful clinical information, but it is difficult to study in the time domain without the aid of a tool such as the method we present here. The primary components of the method are established signal processing techniques, nonparametric regression, and an automatic beat detection algorithm. Some of the insights that can be gained from this are demonstrated through the analysis of intracranial pressure signals acquired from patients with traumatic brain injuries. The analysis indicates the point of transition from low-pressure morphology consisting of three distinct peaks to a high-pressure morphology consisting of a single peak. In addition, we demonstrate how the analysis can reveal distinctions in the relationship between morphology and several signal metrics for different patients.  相似文献   
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