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干部交流工作存在的问题及对策 被引量:3
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作者 王保生 《领导科学》 北大核心 2010年第10Z期36-38,共3页
做好干部交流工作是科学管理干部的重要手段,对于培养和锻炼干部、保持干部队伍的朝气与活力、防范企业经营风险和干部腐败风险等都具有重要意义。实践证明,凡是干部交流工作搞得好的地方和部门,事业发展得快,风气比较正,干部成长也比... 做好干部交流工作是科学管理干部的重要手段,对于培养和锻炼干部、保持干部队伍的朝气与活力、防范企业经营风险和干部腐败风险等都具有重要意义。实践证明,凡是干部交流工作搞得好的地方和部门,事业发展得快,风气比较正,干部成长也比较快。 展开更多
关键词 交流工作 企业经营风险 领导班子结构 交流任职 提拔任用 组织纪律 能力素质 功干 党正 成长规律
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PLC在内燃机车干电阻试验台上的应用
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作者 刘伟 宋夕政 《电脑学习》 1999年第3期11-12,共2页
介绍用FX2素列可编程控制器(PLC)控制内燃机车干电阻耗功装置的系统组成、工作原理、软件编制及运行效果。
关键词 内燃机车 电阻耗装置 试验台 PLC
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Studies on Membrane Function and Sugar Components of Ultradried Seeds 被引量:9
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作者 汪晓峰 景新明 +2 位作者 林坚 郑光华 蔡早 《Acta Botanica Sinica》 CSCD 2003年第1期23-31,共9页
The effects of ultradry storage on the activity of ATPase and fluidity of plasma membrane in Chinese cabbage (Brassica pekinensis (Lour.) Rupr.) and elm ( Ulmus pumila L.) seeds were investigated. The results indicate... The effects of ultradry storage on the activity of ATPase and fluidity of plasma membrane in Chinese cabbage (Brassica pekinensis (Lour.) Rupr.) and elm ( Ulmus pumila L.) seeds were investigated. The results indicated that no significant differences in the activity of ATPase and the micro- viscosity of plasma membrane of ultradried (UD) seeds could be found as compared to the control seeds stored under -20 degreesC, although there was a little adverse effect on the seeds with extreme dehydration. The results were consistent with higher vigor level of UD seeds. This implied that ultradry seed storage could protect the integrity of the membrane, maintain its physiological function and improve the storability of seeds. The relationship between sugar and desiccation tolerance of UD seeds was analysed using the HPLC. The results showed that the ratio of reducing to nonreducing sugar was lower in UD seeds than that in control. The content of sucrose and stachyose in elm and Chinese cabbage UD seeds was related to their desiccation tolerance, while no stachyose was detected in corn (Zea mays L.) seeds. This could be one of the reasons for its sensitivity to desiccation. 展开更多
关键词 ultradry seed storage ATPASE micro-viscosity soluble sugar
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An Efficient MMI SOI Splitter with Multimode Input/Output Waveguides
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作者 方青 贺月娇 +2 位作者 辛红丽 李芳 刘育梁 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期276-280,共5页
A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for... A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for use in fiber optics communication systems.The fabricated device exhibits low loss and good coupling uniformity.The excess loss is lower than 0 8dB,and the uniformity is 0 45dB at the wavelength of 1550nm.Moreover,the polarization dependent loss is lower than 0 7dB at 1550nm.The device size is only 2mm×10mm. 展开更多
关键词 multimode interference power splitter SOI multimode input/output waveguides
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Exo-glycosidases Activities in Artemisia sphaerocephala Mucilaginous Achene Germination Process 被引量:3
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作者 黄振英 Daphne J.OSBORNE 《Acta Botanica Sinica》 CSCD 2002年第11期1380-1383,共4页
白沙蒿 (ArtemisiasphaerocephalaKrasch .)是中国西北沙区分布的多年生植物。瘦果遇湿后其粘液层开始膨胀。对其种子萌发不同阶段的种胚提取物中几种可能降解果皮外层粘液物质的外切糖苷酶进行了检测。结果表明 :β 吡喃半乳糖苷酶在... 白沙蒿 (ArtemisiasphaerocephalaKrasch .)是中国西北沙区分布的多年生植物。瘦果遇湿后其粘液层开始膨胀。对其种子萌发不同阶段的种胚提取物中几种可能降解果皮外层粘液物质的外切糖苷酶进行了检测。结果表明 :β 吡喃半乳糖苷酶在干种子中的活性很高 ,但是随着种子的吸涨而逐渐降低 ,在已萌发的种子中无法探测到。α和 β 吡喃阿拉伯糖苷酶、β 吡喃葡萄糖苷酶以及 β 吡喃甘露糖苷酶在种子萌发过程的胚提取物中也显示出了一些活性 ,但是这些活性在种胚外却无法探测到。所有胚提取物中的外切糖苷酶都无法降解果皮粘液物质。所有的证据都表明果皮外层的粘液物质无法在种子萌发的早期被水解。因此果皮粘液物质在干旱沙质条件下的生态功能被限制在吸收水分以及延长胚吸水的时间。 展开更多
关键词 Artemisia sphaerocephala mucilaginous achene exo-glycosidases ecological function
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Exercise and children's cognition:The role of exercise characteristics and a place for metacognition 被引量:12
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作者 Phillip D.Tomporowski Bryan Mc Cullick +1 位作者 Daniel M.Pendleton Caterina Pesce 《Journal of Sport and Health Science》 SCIE 2015年第1期47-55,共9页
Definitive conclusions concerning the impact of exercise interventions on children's mental functioning are difficult to ascertain because of procedural differences among studies. A narrative review of studies was co... Definitive conclusions concerning the impact of exercise interventions on children's mental functioning are difficult to ascertain because of procedural differences among studies. A narrative review of studies was conducted to evaluate the role of two types of exercise interventions on children's cognition. Acute and chronic exercise interventions were classified as quantitative or qualitative on the basis of manipulations of task complexity and, by inference, mental engagement. Both types of interventions enhance aspects of children's cognition; however, their effects on metacognitive processes are unknown. The role of metacognitive processes and their regulation of children's behavior and academic performance are highlighted. 展开更多
关键词 Academic achievement Child development Executive function Intelligence Memory Mental engagement
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Alpha spectral power and coherence in the patients with mild cognitive impairment during a three-level working memory task 被引量:1
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作者 ZHENG Lei-lei JIANG Zheng-yan YU En-yan 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第8期584-592,共9页
Objective: The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment (MCI) w... Objective: The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment (MCI) was investigated. Methods:Subjects included 35 MCI patients according to the DSM-Ⅳ criteria (mean age: 62.3, SD: 6.5) and 34 healthy controls (mean age:57.4, SD: 4.0) were selected from the community at large. All subjects performed a simple calculation and recall task with three levels of working memory load while electroencephalograph (EEG) signal was recorded. The spectral EEG power was computed over alphal (8.0~10.0 Hz) and alpha2 (10.5~13.0 Hz) frequency bands and was compared between rest stage and working memory processing stage by two-way ANOVA. Post hoc testing analyzed the differences between each two levels of working memory load during task processing. The inter-hemisphere EEG coherence of frontal (F3-F4), central (C3-C4), parietal (P3-P4), temporal (T5-T6) as well as occipital (O1-O2) was compared between MCI patients and normal controls. The EEG signals from F3-C3,F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs resulted from the intra-hemispheric action for alphal and alpha2 frequency bands. Result: There was significantly higher EEG power from MCI patients than from normal controls both at rest and during working memory processing. Significant differences existed between rest condition and three-level working memory tasks (P〈0.001). The inter- and intra-hemispheric coherence during working memory tasks showed a "drop to rise" tendency compared to that at rest condition. There was significantly higher coherence in MCI patients than in the controls.When task difficulties increased, the cortical connectivity of intra-hemispheric diminished while the inter-hemispheric connectivity dominantly maintained the cognitive processing in MCI patients. Conclusion: The results of the present study indicate that the alpha frequency band may be the characteristic band in distinguishing MCI patients from normal controls during working memory tasks. MCI patients exhibit greater inter-hemispheric connectivity than intra-hemispheric connectivity when memory demands increase. MCI patients mobilize a compensatory mechanism to maintain the processing effectiveness while the processing efficiency is reduced. 展开更多
关键词 Spectral power COHERENCE Mild cognitive impairment Working memory
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An enhanced almost blank sub-frame management for efficient elCIC in non-uniform HetNets
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作者 邹尚璋 刘楠 +1 位作者 潘志文 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期14-21,共8页
A new enhanced inter-cell interference coordination (elCIC) is adopted for managing almost blank sub-frame (ABS),which jointly exploits the time, frequency and power dimensions to improve the resource utilization.... A new enhanced inter-cell interference coordination (elCIC) is adopted for managing almost blank sub-frame (ABS),which jointly exploits the time, frequency and power dimensions to improve the resource utilization. In particular, a non-uniform two tier heterogeneous network ( HetNet) is considered, where the pico cells are located close to the macro cell and the number of users in each pico cell is different. To alleviate the interference caused by the co-channeldeployment,the macro cells employ low power ABS (LP- ABS), and the resource blocks (RBs) are divided into twoparts during an ABS. One is exclusively reserved for macro cell users ad the other is reserved for pico cell users. Themacro cells are allowed to use different percentages of RBs and different powers for their own transmission during the LP- ABS. The user association,resource allocation,ABS proportion,the frequency band partition parameter and the transmission power of macro cells are considered, aiming at maximizing the proportional fairness utility of the system. An iterative algorithm is also proposed and simulation results demonstrate that the proposed algorithm can improve both the system throughput and user fairness compared with the existing schemes. 展开更多
关键词 low power almost blank: sub-frame(LP-ABS) inter-cell interference coordination eICIC) non-uniform heterogeneous network (HetNet)
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Identification of voltage sag source location using S and TT transformed disturbance power 被引量:1
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作者 Hussain Shareef Azah Mohamed Ahmad Asrul Ibrahim 《Journal of Central South University》 SCIE EI CAS 2013年第1期83-97,共15页
An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method ... An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method proposed in the literature. Unlike in the case of the traditional method, the proposed method first transforms the recorded voltage and current during the sag event to some special features before calculating the new version of disturbance powers. The effectiveness of the proposed method has been verified through simulation and actual data from an industrial power system. The results show that the presented method can correctly detect the location of voltage sag source. 展开更多
关键词 power quality voltage sag S transform TT transform signal processing
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Regulation of hematopoiesis and the hematopoietic stem cell niche by Wnt signaling pathways 被引量:9
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作者 Michael J Nemeth David M Bodine 《Cell Research》 SCIE CAS CSCD 2007年第9期746-758,共13页
Hematopoietic stem cells (HSCs) are a rare population of cells that are responsible for life-long generation of blood cells of all lineages. In order to maintain their numbers, HSCs must establish a balance between ... Hematopoietic stem cells (HSCs) are a rare population of cells that are responsible for life-long generation of blood cells of all lineages. In order to maintain their numbers, HSCs must establish a balance between the opposing cell fates of self-renewal (in which the ability to function as HSCs is retained) and initiation of hematopoietic differentiation. Multiple signaling pathways have been implicated in the regulation of HSC cell fate. One such set of pathways are those activated by the Wnt family of ligands. Wnt signaling pathways play a crucial role during embryogenesis and deregulation of these pathways has been implicated in the formation of solid tumors. Wnt signaling also plays a role in the regulation of stem cells from multiple tissues, such as embryonic, epidermal, and intestinal stem cells. However, the function of Wnt signaling in HSC biology is still controversial. In this review, we will discuss the basic characteristics of the adult HSC and its regulatory microenvironment, the "niche", focusing on the regulation of the HSC and its niche by the Wnt signaling pathways. 展开更多
关键词 HEMATOPOIESIS hematopoietic stem cell Wnt proteins OSTEOBLAST
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Joint Optimal Sensing Threshold and Subcarrier Power Allocation in Wideband Cognitive Radio for Minimising Interference to Primary User 被引量:3
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作者 刘鑫 贾敏 顾学迈 《China Communications》 SCIE CSCD 2013年第11期70-80,共11页
Cognitive Radio (CR) can use the fre- quency band allocated to a Primary User (PU) on the premise that it will prevent significant of avoiding causing great interference to the PU. In this paper, we consider a wid... Cognitive Radio (CR) can use the fre- quency band allocated to a Primary User (PU) on the premise that it will prevent significant of avoiding causing great interference to the PU. In this paper, we consider a wideband CR system where the Secondary User (SU) mini- raises its interference to the PU by jointly al- locating the optimal sensing threshold and sub- carrier power. A multi-parameter optimization problem is formulated to obtain the joint opt- imal allocation by alternating direction opti- mization, which minimises the total interfer- ence to the PU over all of the subcarriers sub- ject to the constraints on the throughput, Bit Error Rate (BER) and maximal total power of the SU, the subcarrier rate and interference power of the PU, and the false alarm and mis- detection probabilities of each subcarrier. The simulation results show that the proposed joint allocation algorithm can achieve the desired mitigation on the interference to the PU at the different subcarrier gains. 展开更多
关键词 cognitive radio energy detection power allocation INTERFERENCE
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Enhanced recovery for non-colorectal surgery 被引量:4
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作者 Gravante Gianpiero Elmussareh Muhammad 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第3期205-211,共7页
In recent years the advent of programs for enhanced recovery after major surgery (ERAS) has led to modifications of long-standing and well-established perioperative treatments. These programs are used to target factor... In recent years the advent of programs for enhanced recovery after major surgery (ERAS) has led to modifications of long-standing and well-established perioperative treatments. These programs are used to target factors that have been shown to delay postoperative recovery (pain, gut dysfunction, immobility) and combine a series of interventions to reduce perioperative stress and organ dysfunction. With due differences, the programs of enhanced recovery are generally based on the preoperative amelioration of the patient's clinical conditions with whom they present for the operation, on the intraoperative and postoperative avoidance of medications that could slow the resumption of physiological activities, and on the promotion of positive habits in the early postoperative period. Most of the studies were conducted on elective patients undergoing colorectal procedures (either laparotomic or laparoscopic surgery). Results showed that ERAS protocols significantly improved the lung function and reduced the time to resumption of oral diet, mobilization and passage of stool, hospital stay and return to normal activities. ERAS' acceptance is spreading quickly among major centers, as well as district hospitals. With this in mind, is there also a role for ERAS in non-colorectal operations? 展开更多
关键词 Enhanced recovery Length of stay Complications
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POWER CONTROL STRATEGIES FOR MULTICHANNEL COGNITIVE WIRELESS NETWORKS WITH OPPORTUNISTIC INTERFERENCE CANCELLATION
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作者 Tang Zhenzhou Hu Qian Yu Guanding 《Journal of Electronics(China)》 2008年第2期268-273,共6页
In this letter,an Opportunistic Interference Cancellation(OIC) is first introduced as a rate control strategy for secondary user in cognitive wireless networks. Based on the OIC rate control method,an optimal power co... In this letter,an Opportunistic Interference Cancellation(OIC) is first introduced as a rate control strategy for secondary user in cognitive wireless networks. Based on the OIC rate control method,an optimal power control strategy for multichannel cognitive wireless networks is proposed. The algorithm aims to maximize the total transmit rate of cognitive user through appropriately controlling the transmit power of each subchannel under the constraint that the interference temperature at the primary receiver is below a certain threshold. Three suboptimal power control methods,namely Equal Power Transmission(EPT) ,Equal Rate Transmission(ERT) and Equal Interference Transmission(EIT) ,are also proposed. The performances of the proposed power control methods are compared through numerical simulations. 展开更多
关键词 Cognitive wireless networks Interference temperature Power control Interference cancellation
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Optimal Power Allocation for Multiuser Underlay Cognitive Radio Networks under QoS and Interference Temperature Constraints 被引量:2
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作者 徐勇军 赵晓晖 《China Communications》 SCIE CSCD 2013年第10期91-100,共10页
Power allocation is an important issue for Cognitive Radio Networks(CRNs),since it needs to consider the Quality of Service(QoS) for Secondary Users(SUs) while maintaining the interference power to Primary User(PU) be... Power allocation is an important issue for Cognitive Radio Networks(CRNs),since it needs to consider the Quality of Service(QoS) for Secondary Users(SUs) while maintaining the interference power to Primary User(PU) below the Interference Temperature(IT) threshold. In this paper, based on Euclidean projection, we propose a distributed power control algorithm with QoS requirements to minimise the total power consumption of SUs under the time-varying channel scenario. Considering the maximum transmit power constraints and the minimum signal to interference plus noise constraints for each SU, together with the IT constraints for each PU, the power allocation problem is transformed into a convex optimization problem without auxiliary variables, and is solved by the Lagrangian dual method with less information exchange.Simulation results demonstrate that the proposed scheme is superior to the Iterative Water-Filling Algorithm(IWFA). 展开更多
关键词 cognitive radio distributed power allocation Euclidean projection
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Physical Therapy Modalities of Western Medicine and Traditional Chinese Medicine for Meibomian Gland Dysfunction 被引量:2
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作者 LI Jie OU Shang-Kun +2 位作者 LI Wei LIU Zu-Guo PENG Qing-Hua 《Digital Chinese Medicine》 2020年第4期229-238,共10页
The meibomian gland is a unique sebaceous gland located in the eyelid.Its main function is to secrete lipids and form the lipid layer of the tear film to delay the evaporation of waterborne tears,increase the surface ... The meibomian gland is a unique sebaceous gland located in the eyelid.Its main function is to secrete lipids and form the lipid layer of the tear film to delay the evaporation of waterborne tears,increase the surface tension of the tear film,and to lubricate the contact area of the eyelid and eyeball.Abnormal secretion of the meibomian gland is known as meibomian gland dysfunction(MGD),which has become the most important cause of evaporative dry eye disease(DED).The clinical pathophysiological process and underlying molecular mechanisms of MGD are not clear.As serious side effects may occur with the long-term use of hormonotherapy and non-steroidal anti-inflammatory drugs(NSAIDs)for the treatment of MGD,meibomian gland physiotherapy is considered the most effective and safest therapy for MGD.This review summarizes the physical therapy modalities of western medicine(WM)and traditiond Chinese medicine(TCM)for the treatment of MGD to provide optimal treatments for these patients and to further lay a foundation for mechanistic studies of MGD. 展开更多
关键词 Meibomian gland dysfunction(MGD) Dry eye disease Eyelid hygiene LipiFlow Intense pulse light(IPL) Acupuncture Eye fumigation MOXIBUSTION
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电热水壶在使用时应注意哪些安全问题
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作者 苏晓辉 《监督与选择》 2005年第9期35-35,共1页
购买到的电热水壶在使用前,应先仔细阅读说明书,如有不明白的问题,可向销售部门咨询。最初使用电热水壶时,先清洗或加水沸腾两次后倒掉。
关键词 电热水壶 使用安全 触电保护 烧保护
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A Kind of Predator-prey System of Holling Type II and Interaction Perturbation with Impulsive Effect 被引量:1
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作者 GUO Hong-jian ZHAO Zhong +1 位作者 SONG Xin-yu CHEN Lan-sun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期480-490,共11页
A kind of predator-prey system of Holling typeⅡand interaction perturbation with impulsive effect is presented.By using Floquet theory and small amplitude perturbations skills,the locally asymptotical stability of pr... A kind of predator-prey system of Holling typeⅡand interaction perturbation with impulsive effect is presented.By using Floquet theory and small amplitude perturbations skills,the locally asymptotical stability of prey-eradication periodic solution and the permanence of the system are discussed and the corresponding threshold conditions are given respectively.Finally,the existence of positive periodic solution is investigated by the bifurcation theory. 展开更多
关键词 predator-prey system periodic solution threshold asymptotically stable impulsive effect EXTINCTION PERMANENCE
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WNK1: analysis of protein kinase structure, downstream targets, and potential roles in hypertension 被引量:4
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作者 Bing-eXU Byung-HoonLEE +5 位作者 XiaoshanMIN LisaLENERTZ CharlesJHEISE SteveSTIPPEC ElizabethJGOLDSMITH MelanieH.COBB 《Cell Research》 SCIE CAS CSCD 2005年第1期6-10,共5页
The WNK kinases are a recently discovered family of serine-threonine kinases that have been shown to play an essential role in the regulation of electrolyte homeostasis. Intronic deletions in the WNK1 gene result in i... The WNK kinases are a recently discovered family of serine-threonine kinases that have been shown to play an essential role in the regulation of electrolyte homeostasis. Intronic deletions in the WNK1 gene result in its overexpression and lead to pseudohypoaldosteronism type II, a disease with salt-sensitive hypertension and hyperkalemia. This review focuses on the recent evidence elucidating the structure of the kinase domain of WNK1 and functions of these kinases in normal and disease physiology. Their functions have implications for understanding the biochemical mechanism that could lead to the retention or insertion of proteins in the plasma membrane. The WNK kinases may be able to influence ion homeostasis through its effects on synaptotagmin function. 展开更多
关键词 KINASE HYPERTENSION SYNAPTOTAGMIN MAP3K MAP4K ERK5 RNAi.
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Design of MMI 1×8 Optical Power Splitters Used Si-based SiO_2 Waveguide
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作者 WUXiao-jing LUOFeng-guang 《Semiconductor Photonics and Technology》 CAS 2004年第3期168-173,共6页
An initial structure design of MMI 1×8 optical power splitters is reported.The waveguide material is Si-based SiO2 Ge-doped and deposited by PECVD method.Embedded strip structure is implied in the section design.... An initial structure design of MMI 1×8 optical power splitters is reported.The waveguide material is Si-based SiO2 Ge-doped and deposited by PECVD method.Embedded strip structure is implied in the section design.By using BPM-CAD,a favorable result is obtained that this device has a sound uniformity and fairly low loss.Meanwhile,simulations of designs with certain changed parameters is also implemented for a better design configuration. 展开更多
关键词 Optical power splitter Multimode interference WAVEGUIDE
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Methods and Results of Assessment of the Pulse Electrical Disturbances Influence on. Digital Devices Functioning
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作者 Yury Parfenov Boris Titov Leonid Zdoukhov 《Journal of Physical Science and Application》 2013年第6期392-399,共8页
Two methods of calculating the parameters and characterizing the degree of pulse electrical disturbances influence on digital devices functioning, both analytical and numerical, are considered here. The analytical met... Two methods of calculating the parameters and characterizing the degree of pulse electrical disturbances influence on digital devices functioning, both analytical and numerical, are considered here. The analytical method permits one to assess the error occurrence probability in transmitting the data packets considering the dependence on the signal pulses energies-to-pulse disturbances energies ratio and the disturbances repetition frequency-to-data transmission rate ratio and also the dependence on the bits quantity in the packet. The numerical method allows one to assess the specific effect of the repetitive pulse disturbance influence on the digital devices functioning (the number of errors in transmitted data packets, transmission rate, etc.) depending on such factors as the repetition frequency, the disturbance waveform and duration, the mode of data coding, etc.. 展开更多
关键词 Pulse electrical disturbance digital device assessment of influence.
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