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Cheng  Feng  Huang  Yifeng  Tanpure  Bhavana  Sawalani  Pawan  Cheng  Long  Liu  Cong 《Cluster computing》2022,25(1):619-631

As the services provided by cloud vendors are providing better performance, achieving auto-scaling, load-balancing, and optimized performance along with low infrastructure maintenance, more and more companies migrate their services to the cloud. Since the cloud workload is dynamic and complex, scheduling the jobs submitted by users in an effective way is proving to be a challenging task. Although a lot of advanced job scheduling approaches have been proposed in the past years, almost all of them are designed to handle batch jobs rather than real-time workloads, such as that user requests are submitted at any time with any amount of numbers. In this work, we have proposed a Deep Reinforcement Learning (DRL) based job scheduler that dispatches the jobs in real time to tackle this problem. Specifically, we focus on scheduling user requests in such a way as to provide the quality of service (QoS) to the end-user along with a significant reduction of the cost spent on the execution of jobs on the virtual instances. We have implemented our method by Deep Q-learning Network (DQN) model, and our experimental results demonstrate that our approach can significantly outperform the commonly used real-time scheduling algorithms.

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103.
植物非特异性脂质转移蛋白(non-specific lipid transfer proteins,nsLTP)是一类多基因家族编码碱性蛋白,负责脂肪酸体外结和与膜之间的磷脂转移,在植物生长发育和逆境胁迫响应中扮演着重要角色。目前为止,尚无模式植物毛果杨(Populus trichocarpansLTP家族的研究报导。本研究从全基因组水平对PtrnsLTP家族成员的基因数量、亲缘关系、基因结构、编码蛋白保守基序等特性进行了分析,结果表明:PtrnsLTP家族共由39个基因组成,进化成5个亚家族,其中A亚族含有6个基因、B亚族含有2个、C亚族含有13个、D亚族含有3个、E亚族含有15个。PtrnsLTP家族包含7对旁系同源基因,其中1对大于1,6对Ka/Ks均远小于1,且这6对基因均处于同一个大的进化分支上,进化压力的不同导致基因间的功能出现了分化,编码蛋白均含有Motif 1和 Motif 2保守基序。利用qRT-PCR技术并结合杨树转录组数据对PtrnsLTP的组织表达与盐胁迫响应特性研究发现:各家族成员在毛果杨根、茎和叶中均有表达且经qRT-PCR技术验证后与网站预测结果基本吻合,有11、15和13个成员分别在根、茎和叶中有较高的表达,表明该基因家族参与了杨树不同组织的生长发育;NaCl胁迫下,该家族39个基因中分别有26个成员在根部、14个成员在叶部表达量随着胁迫时间的增加而升高,而32个基因在茎部表现为先升高后降低的趋势。本研究结果对于PtrnsLTP家族基因生物学功能的鉴定与盐胁迫响应基因资源的工作有着积极的推动作用。  相似文献   
104.
林窗是森林更新演替的重要环节, 揭示林窗环境下功能性状变异来源及其相对贡献, 有助于阐明植物对林窗环境的响应。该研究以中亚热带格氏栲(Castanopsis kawakamii)天然林为对象, 设置9个不同大小的林窗样地, 运用方差分解探讨林窗、物种和个体对叶性状变异的相对贡献, 采用线性回归分析不同大小林窗下群落性状变化及种间和种内性状变异的重要性。研究发现: (1)格氏栲天然林林窗植物比叶面积、叶干物质含量、叶厚和叶绿素含量由种间性状变异主导, 叶氮含量由种内性状变异主导, 叶磷含量受林窗大小影响最大。(2)群落叶磷含量与林窗大小具有显著正相关关系, 土壤温度和水解氮含量对群落叶磷含量具有显著正效应, 土壤有效磷含量具有显著负效应。(3)沿林冠开放度的群落叶磷含量变化主要由种内性状变异引起, 优势种扮演着重要角色。结果表明, 格氏栲天然林林窗环境下植物功能性状仍以种间性状变异为主(平均41%), 但沿林窗环境梯度的群落性状变化主要源自种内性状变异, 通过植物表型可塑性响应环境改变, 优势种作用明显。  相似文献   
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106.
Atherosclerosis (AS), a progressive disorder, is one of the tough challenges in the clinic. Scutellarin, an extract from Herba Erigerontis, is found to have oxygen-free radicals scavenging effects and antioxidant effects. In this study, we aimed to investigate the anti-AS effects of scutellarin is related to controlling the Hippo–FOXO3A and PI3K/AKT signal pathway. To establish an AS model, the rats in the scutellarin and model groups were intraperitoneally injected with vitamin D 3 and then fed a high-fat diet for 12 weeks. In addition, in vitro angiotensin II-induced apoptosis of human aortic endothelial cells (HAECs) were used to establish models. Scutellarin significantly reduced blood lipid levels and increased antioxidase levels in both models. Additionally, scutellarin inhibited reactive oxygen species generation and apoptosis in HAECs. The impaired vascular barrier function was restored by using scutellarin in AS rats and in HAECs cells characterized by inhibiting mammalian sterile-20-like kinases 1 (Mst1) phosphorylation, Yes-associated protein (YAP) phosphorylation, forkhead box O3A (FOXO3A) phosphorylation at serine 207, nuclear translocation of FOXO3A, and upregulating protein expression of AKT and FOXO3A phosphorylation at serine 253. Scutellarin significantly reduced Bcl-2 interacting mediator of cell death (Bim), caspase-3, APO-1, CD95 (Fas), and Bax: Bcl-2-associated X (Bax) levels and activated Bcl-2: B-cell lymphoma-2 (Bcl-2). Scutellarin also significantly inhibited the expression of Mst1, YAP, FOXO3A at the messenger RNA level. When Mst1 was overexpressed or phosphoinositide 3-kinases suppressed, the effects of scutellarin were significantly blocked. In conclusion, the results of the present study suggest that scutellarin exerts protective effects against AS by inhibiting endothelial cell injury and apoptosis by regulating the Hippo–FOXO3A and PI3K/AKT signal pathways.  相似文献   
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108.
Oxidative stress has been reported to be closely associated with the development of intervertebral disc degeneration (IDD). IDD is one of the major causes of low back pain. Genistein (GES), one of the main isoflavones of soybean, has been shown to exert multiple biological functions on different diseases. Here, we tested the therapeutic potential of GES for IDD. In vitro experiments, we confirmed GES was nontoxic to rat nucleus pulposus cells (NPCs) within the concentration of 100 μM. Furthermore, GES was able to suppress apoptosis in tert-butyl hydroperoxide (TBHP)-treated NPCs. In the aspect of extracellular matrix (ECM), GES not only reduced metalloproteinase-13 (MMP-13) and a disintegrin-like and MMP thrombospondin type 1 motif 5 expression, but also increased aggrecan and type II collagen levels. Also, we found GES might rescue TBHP-induced NPCs degeneration by enhancing Nrf2-mediated antioxidant defense system. Silencing Nrf2 partly abolished the protective effects of GES on apoptosis and ECM disruption in TBHP-treated NPCs. Correspondingly, GES ameliorated IDD in a rat model by preserving morphology of degenerative intervertebral discs and promoting Nrf2 expression. To sum up, our study suggests that GES exerts protective effects in NPCs against degeneration and reveals the underlying mechanism of GES on Nrf2 activation in NPCs.  相似文献   
109.
Chen  Yanting  Chen  Wen  Du  Cong  Fan  Lili  Wang  Wei  Gao  Min  Zhang  Yixin  Cui  Tingkai  Hao  Yunmeng  Pearce  Elizabeth N.  Wang  Chongdan  Zhang  Wanqi 《Biological trace element research》2019,188(1):52-59

Determination of the public health concern about magnesium (Mg) in health and disease has been confounded by the lack of a practical measure of status. This has resulted in a lack of consistency in associating Mg deficiency with specific pathological conditions. Some attempts at associating Mg with a chronic disease have used the Dietary Reference Intakes (DRIs) as a status assessment measure. Use of current DRIs for Mg is problematic because recent evidence suggests that they should be updated and based on body weight. An evidence-based suggested Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) for a 70-kg individual is 175 and 250 mg/day, respectively. However, numerous dietary and physiological factors can affect the need for Mg and thus affect the use of the current or suggested new DRIs to assess Mg status. Calcium intakes above normal requirements can decrease Mg balance and exacerbate signs of Mg deficiency. Mg deficiency apparently occurs often in obesity because of increased need to counteract the inflammatory stress induced by adipose tissue dysfunction. Deficiency in anti-oxidant nutrients such as vitamin E and selenium can exacerbate a response to low dietary Mg indicated by increased oxidative stress which can lead to chronic disease. Dietary modifiers of Mg absorption and excretion affect balance and thus the need for Mg. Factors decreasing Mg balance include low dietary protein and non-fermentable fiber, while factors that can increase balance include fructose and fermentable fiber and fructose-containing oligosaccharides. Use of the DRIs to assess the Mg status of a population or group needs to consider their physiological characteristics and dietary habits and be aware that the DRIs may need updating. The DRIs only can be considered a component of a toolbox that presently includes serum Mg concentration and the daily urinary Mg excretion to assess the Mg status of an individual.

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110.
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