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| 1 | A Differential Evolution Flower Pollination Algorithm with Dynamic Switch Probability显示文摘For the shortcomings of the basic flower pollination algorithm,this paper proposes a differential evolution flower pollination algorithm with dynamic switch probability based on the Weibull distribution.This new algorithm improved the convergence rate and precision.The switch probability is improved by Weibull distribution function combined with the number of iterations.It can balance the relationship between the global pollination and the local pollination to improve the overall optimization performance of the algorithm.Random mutation operator is merged into the global pollination process to increase diversity of the population,enhance the ability of the algorithm’s global search and avoid premature convergence.In the process of local pollination,directed mutation and crossover operation of the differential evolution are incorporated,it makes the individual flower position update with the memory function,which can choose the direction of variation reasonably.The use of cross-operation can avoid new solutions crossing the boundary.Convergence rate is improved and the algorithm can approach the global optimal solution continuously.Theoretical analysis proved the convergence and time complexity of the improved algorithm.The simulation results based on the function optimization problem show that the improved algorithm has better performance of optimization,faster convergence speed and higher convergence accuracy. | LIU Jingsen LIU Li LI Yu | 2019 | Chinese Journal of Electronics2019，28，4： | 9 |
| 2 | LncRNAs-directed PTEN enzymatic switch governs epithelial–mesenchymal transition显示文摘Despite the structural conservation of PTEN with dual-specificity phosphatases,there have been no reports regarding the regulatory mechanisms that underlie this potential dual-phosphatase activity.Here,we report that K27-linked polyubiquitination of PTEN at lysines 66 and 80 switches its phosphoinositide/protein tyrosine phosphatase activity to protein serine/threonine phosphatase activity.Mechanistically,high glucose,TGF-β,CTGF,SHH,and IL-6 induce the expression of a long non-coding RNA,GAEA(Glucose Aroused for EMT Activation),which associates with an RNA-binding E3 ligase,MEX3C,and enhances its enzymatic activity,leading to the K27-linked polyubiquitination of PTEN.The MEX3C-catalyzed PTEN^K27-polyUb activates its protein serine/threonine phosphatase activity and inhibits its phosphatidylinositol/protein tyrosine phosphatase activity.With this altered enzymatic activity,PTEN^K27-polyUb dephosphorylates the phosphoserine/threonine residues of TWIST1,SNAI1,and YAP1,leading to accumulation of these master regulators of EMT.Animals with genetic inhibition of PTEN^K27-polyUb,by a single nucleotide mutation generated using CRISPR/Cas9(Pten^K80R/K80R),exhibit inhibition of EMT markers during mammary gland morphogenesis in pregnancy/lactation and during cutaneous wound healing processes.Our findings illustrate an unexpected paradigm in which the lncRNA-dependent switch in PTEN protein serine/threonine phosphatase activity is important for physiological homeostasis and disease development. | Qingsong Hu Chunlai Li Shouyu Wang Yajuan Li Bo Wen Yanyan Zhang Ke Liang Jun Yao Youqiong Ye Heidi Hsiao Tina K.Nguyen Peter K.Park Sergey D.Egranov David H.Hawke Jeffrey R.Marks Leng Han Mien-Chie Hung Bing Zhang Chunru Lin Liuqing Yang | 2019 | Cell Research2019，29，4： | 8 |
| 3 | Stability of a linear oscillator with damping force of the fractional-order derivative显示文摘It begins with the study of damping representation of a linear vibration system of single degree of freedom (SDOF),from the view point of fractional calculus. By using the idea of stability switch,it shows that the linear term involving the fractional-order derivative of an order between 0 and 2 always acts as a damping force,so that the unique equilibrium is asymp-totically stable. Further,based on the idea of stability switch again,the paper proposes a scheme for determining the stable gain region of a linear vibration system under a fractional-order control. It shows that unlike the classical velocity feedback which can adjust the damping force only,a fractional-order feedback can adjust not only the damping force,but also the elastic re-storing force,and in addition,a fractional-order PDα control can either enlarge the stable gain region or narrow the stable gain region. For the dynamic systems described by integer-order derivatives,the asymptotical stability of an equilibrium is guaranteed if all characteristic roots stay in the open left half-plane,while for the systems with fractional-order derivatives,the asymptotical stability of an equilibrium is guaranteed if all characteristic roots stay within a sector in the complex plane. Analysis shows that the proposed method,based on the idea of stability switch,works effectively in the stability analysis of dynamical systems with fractional-order derivatives. | WANG ZaiHua1,2 & HU HaiYan1 1 Institute of Vibration Engineering Research,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China 2 Institute of Science,PLA University of Science and Technology,Nanjing 211101,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，2： | 7 |
| 4 | 基于MEMS技术的光通信器件及其市场前景显示文摘介绍了基于MEMS技术的光通信器件主要制造商及其产品情况,并概要分析了MEMS光器件的市场前景和发展方向。 | 吴国锋 | 2003 | 光通信技术2003，27，6： | 6 |
| 5 | APOBEC deaminases-mutases with defensive roles for immunity显示文摘In recent years, tremendous progress has been made in the elucidation of the biological roles and molecular mechanisms of the apolioprotein B mRNA-editing enzyme catalytic polypeptide (APOBEC) family of enzymes. The APOBEC family of cytidine deaminases has important functional roles within the adaptive and innate immune system. Activation induced cytidine deaminase (AID) plays a central role in the biochemical steps of somatic hypermutation and class switch recombination during antibody maturation, and the APOBEC 3 enzymes are able to inhibit the mobility of retroelements and the replication of retroviruses and DNA viruses, such as the human immunodeficiency virus type-1 and hepatitis B virus. Recent advances in structural and functional studies of the APOBEC enzymes provide new biochemical insights for how these enzymes carry out their biological roles. In this review, we provide an overview of these recent advances in the APOBEC field with a special emphasis on AID and APOBEC3G. | Courtney PROCHNOW Ronda BRANSTEITTER | 2009 | Science China(Life Sciences)2009，52，10： | 6 |
| 6 | Tumor progression-dependent angiogenesis in gastric cancer and its potential application显示文摘Despite improvements in the early diagnosis,prognosis and therapeutic strategies for gastric cancer(GC),human GC remains one of the most frequently diagnosed malignant tumors in the world,and the survival rate of GC patients remains very poor.Thus,a suitable therapeutic strategy for GC is important for prolonging survival.Both tumor cells themselves and the tumor microenvironment play an important role in tumorigenesis,including angiogenesis,inflammation,immunosuppression and metastasis.Importantly,these cells contribute to gastric carcinogenesis by altering the angiogenic phenotype switch.The development,relapse and spreading of tumors depend on new vessels that provide the nutrition,growth factors and oxygen required for continuous tumor growth.Therefore,a state of tumor dormancy could be induced by blocking tumor-associated angiogenesis.Recently,several antiangiogenic agents have been identified,and their potential for the clinical management of GC has been tested.Here,we provide an up-to-date summary of angiogenesis and the angiogenic factors associated with tumor progression in GC.We also review antiangiogenic agents with a focus on the anti-vascular endothelial growth factor receptor(VEGFR)-mediated pathway for endothelial cell growth and their angiogenesis ability in GC.However,most antiangiogenic agents have reported no benefit to overall survival(OS)compared to chemotherapy alone in local or advanced GC.In phase III clinical trials,only ramucirumab(anti-VEGFR blocker)and apatinib(VEGFR-TKI blocker)have reported an improved median overall response rate and prolonged OS and progression-free survival outcomes as a 2 nd-line agent combined with chemotherapy treatment in advanced GC.By providing insights into the molecular mechanisms of angiogenesis associated with tumor progression in GC,this review will hopefully aid the optimization of antiangiogenesis strategies for GC therapy in combination with chemotherapy and adjuvant treatment. | Hsi-Lung Hsieh Ming-Ming Tsai | 2019 | World Journal of Gastrointestinal Oncology2019，11，9： | 6 |
| 7 | 基于TOP Switch反激式高精度开关电源的设计显示文摘文中以TOP222为例介绍了TOP Switch单片开关电源的工作原理及设计要点,设计了输入输出电路、箝位电路及反馈控制电路,介绍了用PI Exper设计单片开关电源高频变压器的方法步骤,并用该软件设计了反激式电源的高频变压器。在介绍原理、设计电路的基础上研制了2路输出高精度反激式电源,实验结果完全符合技术指标要求,证实了文中原理分析及设计方法的正确性。 | 徐艳霞 | 2012 | 通信电源技术2012，29，6： | 4 |
| 8 | 多维色谱技术应用于汽油中甲缩醛、酯类、苯胺类非常规添加剂的测定显示文摘采用微板流路控制技术,以Deans Switch及Quick Swap组件组成的多维色谱,通过串联预分离色谱柱(非极性色谱柱:RB-1)分别与分析色谱柱(强极性色谱柱:RB-Oxy PLOT、极性色谱柱:RB-INNOwax)串联以中心切割及反吹技术,实现一次进样快速准确地对汽油中的甲缩醛、酯类及苯胺类非常规添加剂进行定性和定量测定;其特点是无需进行样品前处理,避免样品因萃取转移损失造成误差,从而提高了方法的准确度及检测效率。实验结果表明:通过内标法定量所建立的甲基叔丁基醚、二异丙醚、甲基叔戊基醚、甲醇、甲缩醛、乙醇、乙酸乙酯、碳酸二甲酯、正丙醇、异丙醇、异丁醇、仲丁醇、叔丁醇、正丁醇、乙酸仲丁酯、叔戊醇16种含氧化合物的校正曲线,相关性良好,线性范围为0.1~10g·L^(-1),相关系数均在0.999以上,16种含氧类添加剂的检出限为0.0341 g·L^(-1)~0.0483g·L^(-1)。同时,N,N-二甲基苯胺、N-甲基苯胺、邻甲基苯胺、间甲基苯胺、对甲基苯胺和苯胺等6种苯胺类化合物的校正曲线,相关性良好,线性范围为0.1~10g·L^(-1),相关系数均在0.99以上,6种苯胺类添加剂的检出限为0.0392 g·L^(-1)~0.0948g·L^(-1)。此方法适用于汽油中甲缩醛、酯类及苯胺类非常规添加剂组分含量的测定,检测范围为0.01%~10%质量分数。 | 贾瑞 李莹 王斌 段斌 董志强 何剑威 刘义国 | 2017 | 山东化工2017，46，2： | 4 |
| 9 | 飞利浦iE33彩超无法使用On/Off Switch关机故障排查显示文摘iE33是飞利浦旗下专为心脏和血管检查而设计的科研级高端彩超,本研究就设备出现无法使用On/Off Switch关机故障进行分析排查,从而更好地了解电源工作原理,方便日后解决相关的问题。 | 黄载全 | 2017 | 医疗装备2017，30，14： | 3 |
| 10 | Ikaros in B cell development and function显示文摘The zinc finger transcription factor,Ikaros,is a central regulator of hematopoiesis.It is required for the development of the earliest B cell progenitors and at later stages for VDJ recombination and B cell receptor expression.Mature B cells rely on Ikaros to set the activation threshold for various stimuli,and to choose the correct antibody isotype during class switch recombination.Thus,Ikaros contributes to nearly every level of B cell differentiation and function. | MacLean Sellars Philippe Kastner Susan Chan | 2011 | World Journal of Biological Chemistry2011，2，6： | 3 |
| 11 | MicroRNA-188 regulates age-related switch between osteoblast and adipocyte differentiation显示文摘Granted by the National Science Foundation for Distinguished Young Scholars of China,Prof.Luo Xianghang’s team from the Institute of Endocrinology and Metabolism,Second Xiangya Hospital,Central South University,reported that microRNA-188regulates age-related switch between osteoblast and adipocyte differentiation.Their work has been published in J Clin Invest(2015,125(4):1509—22). | | 2015 | Science Foundation in China2015，23，4： | 3 |
| 12 | 基于L6562A的两级式PFC电路的研究显示文摘开关电源在电源领域中以其高效率、低功耗、高能量密度、电压适用范围广等优点在各行各业得到大量的应用。然而,其输入电流并非跟踪电压变化,含有大量的奇次谐波电流,对电网造成大量的谐波污染。对比现有两级式和单级式两种形式的PFC电源,运用L6562A芯片将TOPswitch227功率集成芯片应用于两级式PFC电路中,简化了两级PFC电路结构,并通过实验验证了所研究电路的可行性。 | 房绪鹏 李辉 庄见伟 许玉林 赵志远 许伟 | 2016 | 电子器件2016，39，5： | 3 |
| 13 | Sandman is a Sleep Switch in Drosophila显示文摘Sleep is a universal process with vital functions.Animals deprived of sleep for a long period of time will die.Despite its crucial functions,fundamental questions about sleep remain unexplored.For instance,why do animals sleep since it disconnects animals from the external world and exposes them to danger(we really do not know!)?What is the switch between sleep and waking,if there is one(we may be beginning to understand this!)? | Yufeng Pan | 2016 | Neuroscience Bulletin2016，32，5： | 3 |
| 14 | Treatment strategies for multiple sclerosis:When to start,when to change,when to stop?显示文摘Multiple sclerosis(MS) is a chronic inflammatory condition of the central nervous system determined by a presumed autoimmune process mainly directed against myelin components but also involving axons and neurons. Acute demyelination shows as clinical relapses that may fully or partially resolve, while chronic demyelination and neuroaxonal injury lead to persistent and irreversible neurological symptoms, often progressing over time. Currently approved disease-modifying therapies are immunomodulatory or immunosuppressive drugs that significantly although variably reduce the frequency of attacks of the relapsing forms of the disease. However, they have limited efficacy in preventing the transition to the progressive phase of MS and are of no benefit after it has started. It is therefore likely that the potential advantage of a given treatment is condensed in a relatively limited window of opportunity for each patient, depending on individual characteristics and disease stage, most frequently but not necessarily in the early phase of the disease. In addition, a sizable proportion of patients with MS may have a very mild clinical course not requiring a disease-modifying therapy. Finally, individual response to existing therapies for MS varies significantly across subjects and the risk of serious adverse events remains an issue, particularly for the newest agents. The present review is aimed at critically describing current treatment strategies for MS with a particular focus on the decision of starting, switching and stopping commercially available immunomodulatory and immunosuppressive therapies. | Alberto Gajofatto Maria Donata Benedetti | 2015 | World Journal of Clinical Cases2015，3，7： | 2 |
| 15 | A Virtual Machine Scheduling Strategy with a Speed Switch and a Multi-Sleep Mode in Cloud Data Centers显示文摘With the rapid growth of energy costs and the constant promotion of environmental standards, energy consumption has become a significant expenditure for the operating and maintaining of a cloud data center. Io improve the energy efficiency of cloud data centers, in this paper, we propose a Virtual Machine (VM) scheduling strategy with a speed switch and a multi-sleep mode. In accordance with the current traffic loads, a proportion of VMs operate at a low speed or a high speed, while the remaining VMs either sleep or operate at a high speed. Commensurate with our proposal, we develop a continuous-time queueing model with an adaptive service rate and a partial synchronous vacation. We construct a two dimensional Markov chain based on the total number of requests in the system and the state of all the VMs. Using a matrix geometric solution, we mathematically estimate the energy saving level and the response performance of the system. Numerical experiments with analysis and simulation show that our proposed VM scheduling strategy can effectively reduce the energy consumption without significant degradation in response performance. Additionally;we establish a system utility function to trade off the different performance measures. In order to determine the optimal sleep parameter and the maximum system utility function, we develop an improved Firefly intelligent searching Algorithm. | Shunfu Jin Shanshan Hao Xiuchen Qie Wuyi Yue | 2019 | Journal of Systems Science and Systems Engineering2019，28，2： | 2 |
| 16 | Nonvolatile waveguide transmission tuning with electrically-driven ultra-small GST phase-change material显示文摘Low-power reconfigurable optical circuits are highly demanded to satisfy a variety of different applications. Conventional electro-optic and thermo-optic refractive index tuning methods in silicon photonics are not suitable for reconfiguration of optical circuits due to their high static power consumption and volatility. We propose and demonstrate a nonvolatile tuning method by utilizing the reversible phase change property of GST integrated on top of the silicon waveguide. The phase change is enabled by applying electrical pulses to the lm-sized GST active region in a sandwich structure. The experimental results show that the optical transmission of the silicon waveguide can be tuned by controlling the phase state of GST. | Hanyu Zhang Linjie Zhou Jian Xu Ningning Wang Hao Hu Liangjun Lu B. M. A. Rahman Jianping Chen | 2019 | Science Bulletin2019，64，11： | 2 |
| 17 | Single-molecule optoelectronic devices:physical mechanism and beyond显示文摘Single-molecule devices not only promise to provide an alternative strategy to break through the miniaturization and functionalization bottlenecks faced by traditional semiconductor devices,but also provide a reliable platform for exploration of the intrinsic properties of matters at the single-molecule level.Because the regulation of the electrical properties of single-molecule devices will be a key factor in enabling further advances in the development of molecular electronics,it is necessary to clarify the interactions between the charge transport occurring in the device and the external fields,particularly the optical field.This review mainly introduces the optoelectronic effects that are involved in single-molecule devices,including photoisomerization switching,photoconductance,plasmon-induced excitation,photovoltaic effect,and electroluminescence.We also summarize the optoelectronic mechanisms of single-molecule devices,with particular emphasis on the photoisomerization,photoexcitation,and photo-assisted tunneling processes.Finally,we focus the discussion on the opportunities and challenges arising in the single-molecule optoelectronics field and propose further possible breakthroughs. | Peihui Li Yijian Chen Boyu Wang Mengmeng Li Dong Xiang Chuancheng Jia Xuefeng Guo | 2022 | Opto-Electronic Advances2022，5，5： | 2 |
| 18 | 石墨型高能两电极气体开关显示文摘为大型激光装置能源模块研制了一种采用石墨电极的两电极气体开关,阐述了石墨应用于高能两电极气体开关的技术关键,对气体开关中气体间隙的最优结构进行了电场强度分析。参考美国国家点火装置(NIF)能源模块中ST-300气体开关的已知参数,对研制成功的石墨型两电极开关进行了电气特性试验,证明了石墨型气体开关能够实现峰值电流达300 kA以上,单次转移电荷量100 C以上,寿命超过1 000次,满足1.2 MJ大型激光装置能源模块的工程技术要求。 | 郭良福 李黎 赖贵友 林福昌 陈德怀 力一峥 李冬梅 栾永平 | 2010 | 强激光与粒子束2010，22，12： | 2 |
| 19 | SIP协议的研究与应用显示文摘本文介绍了会话初始协议(SIP协议),分析了SIP的系统构成和工作原理,阐述了SIP在软交换和3G移动通信中的应用,对SIP的未来做出了展望。 | 宋薇 胡广 | 2009 | 湖北广播电视大学学报2009，29，4： | 2 |
| 20 | Functions and applications of polypyridyl complexes in DNA显示文摘The syntheses and desymmetration of a series of novel polypyridyl ligands as well as their complexes, and their DNA-binding properties are reported in this review. The stresses are focused on the functions and potential applications of such complexes as DNA structural probe, DNA molecular light switches, anti-cancer drugs, and photoactivated cleavage agents. | Ji, LN Zhang, QL Chao, H | 2001 | Chinese Science Bulletin2001，46，16： | 2 |
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