MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a hea...MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a heartbeat mechanism for MapReduce Task Scheduler using Dynamic Calibration （HMTS- DC） is proposed to address the unbalanced node computation capacity problem in a het- erogeneous MapReduce environment. HMTS- DC uses two mechanisms to dynamically adapt and balance tasks assigned to each com- pute node： 1） using heartbeat to dynamically estimate the capacity of the compute nodes, and 2） using data locality of replicated data blocks to reduce data transfer between nodes. With the first mechanism, based on the heart- beats received during the early state of the job, the task scheduler can dynamically estimate the computational capacity of each node. Us- ing the second mechanism, unprocessed Tasks local to each compute node are reassigned and reserved to allow nodes with greater capacities to reserve more local tasks than their weaker counterparts. Experimental results show that HMTS-DC performs better than Hadoop and Dynamic Data Placement Strategy （DDP） in a dynamic environment. Furthermore, an en- hanced HMTS-DC （EHMTS-DC） is proposed bv incorporatin historical data. In contrastto the ＂slow start＂ property of HMTS-DC, EHMTS-DC relies on the historical computation capacity of the slave machines. The experimental results show that EHMTS-DC outperforms HMTS-DC in a dynamic environment.展开更多
DNA病毒基因组的编码能力有限,在其基因组复制过程中与细胞内的DNA损伤反应(DDR)信号网络发生复杂广泛的相互作用,创造利于病毒复制的细胞内环境。MRN复合物(MRE11-RAD50-NBS1)、复制蛋白A(RPA)分别识别DNA双链断裂(DSB)和单链断裂(SSB)...DNA病毒基因组的编码能力有限,在其基因组复制过程中与细胞内的DNA损伤反应(DDR)信号网络发生复杂广泛的相互作用,创造利于病毒复制的细胞内环境。MRN复合物(MRE11-RAD50-NBS1)、复制蛋白A(RPA)分别识别DNA双链断裂(DSB)和单链断裂(SSB)。DNA病毒选择性地激活磷脂酰肌醇-3激酶样激酶(PI3KK)ATM(Ataxia telangiectasia mutated)、ATR(Ataxia telangiectasia and Rad3related)或DNA-PKcs(DNA-dependent protein kinase catalytic subunit),通过调控细胞周期进展、启动非同源末端连接(NHEJ)和同源重组修复(HRR)等不同的DNA修复途径,选择性地激活利用或抑制降解宿主细胞DDR组分来完成其感染周期,表现在病毒复制中心(VRC)处募集结合了不同的参与细胞DNA损伤和修复的蛋白质。综述了DNA病毒复制与宿主细胞DDR信号网络的互作机制,旨在为研究DNA病毒的复制和致病分子机制提供思路。展开更多
文摘MapReduce is a popular program- ming model for processing large-scale datasets in a distributed environment and is a funda- mental component of current cloud comput- ing and big data applications. In this paper, a heartbeat mechanism for MapReduce Task Scheduler using Dynamic Calibration （HMTS- DC） is proposed to address the unbalanced node computation capacity problem in a het- erogeneous MapReduce environment. HMTS- DC uses two mechanisms to dynamically adapt and balance tasks assigned to each com- pute node： 1） using heartbeat to dynamically estimate the capacity of the compute nodes, and 2） using data locality of replicated data blocks to reduce data transfer between nodes. With the first mechanism, based on the heart- beats received during the early state of the job, the task scheduler can dynamically estimate the computational capacity of each node. Us- ing the second mechanism, unprocessed Tasks local to each compute node are reassigned and reserved to allow nodes with greater capacities to reserve more local tasks than their weaker counterparts. Experimental results show that HMTS-DC performs better than Hadoop and Dynamic Data Placement Strategy （DDP） in a dynamic environment. Furthermore, an en- hanced HMTS-DC （EHMTS-DC） is proposed bv incorporatin historical data. In contrastto the ＂slow start＂ property of HMTS-DC, EHMTS-DC relies on the historical computation capacity of the slave machines. The experimental results show that EHMTS-DC outperforms HMTS-DC in a dynamic environment.
文摘DNA病毒基因组的编码能力有限,在其基因组复制过程中与细胞内的DNA损伤反应(DDR)信号网络发生复杂广泛的相互作用,创造利于病毒复制的细胞内环境。MRN复合物(MRE11-RAD50-NBS1)、复制蛋白A(RPA)分别识别DNA双链断裂(DSB)和单链断裂(SSB)。DNA病毒选择性地激活磷脂酰肌醇-3激酶样激酶(PI3KK)ATM(Ataxia telangiectasia mutated)、ATR(Ataxia telangiectasia and Rad3related)或DNA-PKcs(DNA-dependent protein kinase catalytic subunit),通过调控细胞周期进展、启动非同源末端连接(NHEJ)和同源重组修复(HRR)等不同的DNA修复途径,选择性地激活利用或抑制降解宿主细胞DDR组分来完成其感染周期,表现在病毒复制中心(VRC)处募集结合了不同的参与细胞DNA损伤和修复的蛋白质。综述了DNA病毒复制与宿主细胞DDR信号网络的互作机制,旨在为研究DNA病毒的复制和致病分子机制提供思路。
