血清趋化素水平与慢性心力衰竭患者左室重构的相关性研究

目的通过测定慢性心力衰竭(以下简称心衰)患者血清趋化素表达水平,探讨其与心衰及心室重构的相关性。方法纳入60例慢性心衰患者,心功能Ⅱ级16例,心功能Ⅲ级26例,心功能Ⅳ级18例,应用超声心动图测定射血分数、左房内径、左室舒张末期内径、室间隔厚度、左室后壁厚度,计算左室质量和左室质量指数。另设同期住院的心功能正常患者60例为对照组,测定所有患者的血清趋化素表达水平。结果心衰组血清趋化素表达水平高于对照组,且随心衰程度的加重而升高(P<0.05),血清趋化素表达水平与左室质量指数呈正相关(r=0.401,P=0.022),与左室射血分数呈负相关(r=-0.455,P=0.021)。结论血清趋化素作为一个新的心衰标志物,可以评估心衰的程度、判断心衰的预后,且趋化素与左室重构相关,对其进行干预可能有助于心衰的治疗。

Environment-Stable CoxNiy Encapsulation in Stacked Porous Carbon Nanosheets for Enhanced Microwave Absorption

Magnetic/dielectric@porous carbon composites,derived from metal–organic frameworks(MOFs)with adjustable composition ratio,have attracted wide attention due to their unique magnetoelectric properties.In addition,MOFs-derived porous carbon-based materials can meet the needs of lightweight feature.This paper reports a simple process for synthesizing stacked CoxNiy@C nanosheets derived from CoxNiy-MOFs nanosheets with multiple interfaces,which is good to the microwave response.The CoxNiy@C with controllable composition can be obtained by adjusting the ratio of Co^2+ and Ni^2+.It is supposed that the increased Co content is benefit to the dielectric and magnetic loss.Additionally,the bandwidth of CoNi@C nanosheets can take up almost the whole Ku band.Moreover,this composite has better environmental stability in air,which characteristic provides a sustainable potential for the practical application.

Optimal Design of Multi-channel Water Cooled Radiator for Motor Controller of New Energy Vehicle

In order to improve the heat dissipation capability of motor controller for new energy vehicles,the water cooled radiator with multiple channels is optimized in this paper.The heat conduction between the heat source IGBT and the radiator,the convective heat transfer between the radiator and the coolant,the mechanical strength and the manufacturing cost are comprehensively considered during the optimization process.The power loss and thermal resistance of the IGBT unit are calculated at first,and finite element model of the radiator is established.On this basis,multi-physics coupling analysis of the water cooled radiator is carried out.Secondly,the sensitivity analysis is applied to verify the influence of structural parameters on the heat dissipation performance of the radiator system.The influence of coolant inlet velocity v,number of cooling ribs n,height of radiator ribs H on the maximum temperature rise T,the temperature difference ΔT between phase U and W,and the coolant pressure lossΔP are analyzed in depth,and the optimal range of the structural parameters for heat dissipation is obtained.Finally,an experimental platform was set up to verify the performance of the proposed structure of water cooled radiator for motor controller of new energy vehicle.The results show that the heat dissipation capability of the proposed radiator is improved compared with the initial design.

运动员对教练信任的前因后果

目的:评估运动员对教练的信任如何影响其对教练的忠诚、与教练的合作意愿及感知表现。方法:215名竞技体育俱乐部会员回答了关于教练员的公正、仁慈、正直和能力方面特质的问题。进行了运动员对教练的信任、忠诚、合作意愿及其感知表现等级的测试。结果:对数据的验证性因素分析支持了测量模型。运动员对教练公正(β=0.19,p<0.05)、仁慈(β=0.32,p<0.05)、正直(β=0.14,p<0.05)和能力(β=0.29,p<0.05)方面的感知对其信任感有显著影响。在信任变量中,这些因素累积占61%。结构型方程模型显示:信任感直接影响忠诚(β=0.77,p<0.01)、合作意愿(β=0.79,p<0.01)及感知表现(β=0.51,p<0.01);忠诚及合作意愿有调节作用的假设未得到支持;感知表现变量占26%由此模式得到解释。结论:由于运动员对教练员的信任影响其对教练的忠诚、合作意愿及感知表现,因此教练员需要做到公正、仁慈,提高自身正直感和能力,从而提升运动员对其信任度。

Performance Prediction of Switched Reluctance Motor using Improved Generalized Regression Neural Networks for Design Optimization

Since practical mathematical model for the design optimization of switched reluctance motor(SRM)is difficult to derive because of the strong nonlinearity,precise prediction of electromagnetic characteristics is of great importance during the optimization procedure.In this paper,an improved generalized regression neural network(GRNN)optimized by fruit fly optimization algorithm(FOA)is proposed for the modeling of SRM that represent the relationship of torque ripple and efficiency with the optimization variables,stator pole arc,rotor pole arc and rotor yoke height.Finite element parametric analysis technology is used to obtain the sample data for GRNN training and verification.Comprehensive comparisons and analysis among back propagation neural network(BPNN),radial basis function neural network(RBFNN),extreme learning machine(ELM)and GRNN is made to test the effectiveness and superiority of FOA-GRNN.

New mechanism of partial duplication and deletion of chromosome 8:A case report

BACKGROUND During meiosis,the recombination of homologous chromosomes produces some new heritable mutations,which are the basis of biological evolution and diversity.However,when there is pericentric inversion of chromosomes,unbalanced gametes will be formed in the process of germ cell meiosis.CASE SUMMARY A 23-year-old pregnant woman at 25 wk of gestation wanted to terminate her pregnancy due to fetal chromosomal abnormalities.She had no exposure to toxic or hazardous substances before and during pregnancy,no history of medication usage during pregnancy,and she underwent cystectomy of ovarian cysts in 2017.On the second day of the 16th week of gestation,non-invasive prenatal testing showed chromosome 8 copy number variation.Following genetic counseling,her pregnancy was terminated.CONCLUSION Recombinant offspring chromosome is rarely seen when the inversion segment is shorter than one-third of the chromosome length.In terms of the mechanism of chromosome 8 duplication/deletion occurrence,attention should be paid to the production of unbalanced gametes by the pairing of homologous chromosome during meiosis,and the possibility of mitotic recombination exchange as well.

Comorbidities and high in-hospital mortality of cancer-associated pulmonary embolism:findings from a real-world registry study

To the Editor:Cancer has been recognized as an independent predisposing factor of venous thromboembolism(VTE),including pulmonary embolism(PE)and deep vein thrombosis(DVT).Patients with cancer have a sevenfold increased risk of VTE compared with those without cancer.[1]Evidence from autopsy in cancer patients showed that PE is an important disease complication in patients with cancer.[2]Optimal management of PE patients with cancer has become a major concern that challenges clinicians in daily clinical practice.Understanding the risk factors of all-cause death in PE patients with cancer in the real world may enable optimal management and improve their survival.Therefore,this study was performed to characterize cancerassociated PE and evaluate the clinical predictors of inhospital death based on the data of PE patient population in China.

Temperature‐dependent adaptive conductivity coating for surface charge release and electric field control under electro‐thermal coupling field

Surface charge accumulation is the potential criminal for surface insulation failure on spacers under direct current(DC)voltages.The existence of thermal gradient posing the difficulty of surface charge regulation.This study proposes a temperature‐dependent adaptive conductivity coating technique for surppressing surface charge accumulation under electro‐thermal coupling field.A two‐dimensional axis‐symmetrical simulation model regrading surface charge computation is established.The effects of thermal gradients and coating conductivity on surface charge and electric field distribution are investigated.The results show that the thermal gradient increases the bulk conductive current,therefore aggravating surface charge accumulation.The effects of the coating condcutivity on surface charge and electric field contains three stages.The lower coating conductivity leads to aggravated homo‐polarity charge accumulation.By increasing the coating conductivity,the surface charge and electric field are significantly suppressed at the obtained optimal conductivity,where the bulk and surface conductive current reach a balance stage.Continuously increasing the coating conductivity results in aggravated hetero‐polarity charges.Besides,the increase of thermal gradient to an appropriate extent contributes to the further suppression of surface charge on coated spacers.It is hoped that this study could provide some references for designing highly reliable DC GIL under electro‐thermal coupling field.

具有芳并咪唑结构单元的叶绿素类二氢卟吩衍生物的合成

以脱镁叶绿酸-a甲酯为起始原料,利用其外接环的结构转换,在N^(21)-N^(23)轴水溶性端向的不同位置上构建了甲酰基和邻位二酮结构;通过连有活性官能团的叶绿素类二氢卟吩与多种芳香邻位二胺进行类Phillps-Ladenburg反应,以连接和并合的方式在其周环上引进了芳并咪唑结构单元;完成了一系列未见报道的具有芳并咪唑结构单元的叶绿素类二氢卟吩衍生物的合成,讨论了相应的反应机理和咪唑化产物的紫外-可见光谱性质.所有新合成化合物的结构均经UV-Vis、IR、^(1)H NMR、MS及元素分析予以证实.

An IP mobility management scheme with dual location areas for IP/LEO satellite network

One of the issues of mobility management in a low Earth orbit (LEO) satellite network is the high-frequency location binding update initiated by mobile nodes (MNs).To solve this problem,we propose a location management scheme based on dual location area (LA) in an IP/LEO satellite network.The proposed scheme uses two kinds of LA,the fixed Earth station LA and satellite LA,to manage the location of the MNs together.MNs operate the binding update procedures only when they are moving out of both of the two LAs last registered.Geographical location information of MN is used in the binding update procedures,so that the network can page the idle MNs near their last registered location first,to enhance the probability of paging success.A detailed description of the implementation of the scheme is provided.Mathematical analysis shows that the proposed scheme reduces the location management cost and minimizes the influences of the distance between MN and its home agent.Paging cost is also reduced by introducing geographical location information in the binding update procedures.

寒喘祖帕颗粒联合中医护理措施干预支气管哮喘发作期临床研究

目的:观察在常规医护措施基础上加用中医护理措施及口服寒喘祖帕颗粒干预支气管哮喘发作期的临床疗效。方法:将100例符合要求的外寒内饮型支气管哮喘发作期患者随机分为观察组和对照组各50例。2组均予沙丁胺醇气雾剂吸入治疗,并给予认知教育、心理护理、饮食护理等护理措施。观察组加予服用寒喘祖帕颗粒,并给予中医护理措施。2组疗程均为1周。治疗前、治疗1周后评价喘息、咳嗽、咯痰、胸膈满闷和喉中哮鸣声等症状评分;测量第1秒用力呼气容积(FEV_(1))、最大呼气流量(PEF),并计算FEV_(1)占预计值的百分比(FEV_(1)%)、PEF占预计值的百分比(PEF%)和PEF昼夜波动率。治疗1周后评价护理满意度。结果:治疗后,观察组临床疗效优于对照组(P<0.05)。2组临床症状积分与PEF%值均较治疗前下降,FEV_(1)%值均较治疗前升高,差异均有统计学意义(P<0.01);观察组临床症状积分与PEF%值均低于对照组,FEV_(1)%值高于对照组,差异均有统计学意义(P<0.01)。观察组护理满意度高于对照组(P<0.05)。结论:在现代医学常规医护措施基础上给予中医护理措施和寒喘祖帕颗粒内服治疗外寒内饮型支气管哮喘发作期可更好地控制哮喘发作症状,改善肺功能,提高临床疗效和患者对护理工作的满意度。

The Boltzmann Equation with Time-periodic Boundary Temperature

This paper is concerned with the boundary-value problem on the Boltzmann equation in bounded domains with diffuse-reflection boundary where the boundary temperature is time-periodic. We establish the existence of time-periodic solutions with the same period for both hard and soft potentials, provided that the time-periodic boundary temperature is sufficiently close to a stationary one which has small variations around a positive constant. The dynamical stability of time-periodic profiles is also proved under small perturbations, and this in turn yields the non-negativity of the profile. For the proof, we develop new estimates in the time-periodic setting.

Heat Transfer Problem for the Boltzmann Equation in a Channel with Diffusive Boundary Condition

In this paper,the authors study the 1 D steady Boltzmann flow in a channel.The walls of the channel are assumed to have vanishing velocity and given temperaturesθ0andθ1.This problem was studied by Esposito-Lebowitz-Marra(1994,1995)where they showed that the solution tends to a local Maxwellian with parameters satisfying the compressible Navier-Stokes equation with no-slip boundary condition.However,a lot of numerical experiments reveal that the fluid layer does not entirely stick to the boundary.In the regime where the Knudsen number is reasonably small,the slip phenomenon is significant near the boundary.Thus,they revisit this problem by taking into account the slip boundary conditions.Following the lines of[Coron,F.,Derivation of slip boundary conditions for the Navier-Stokes system from the Boltzmann equation,J.Stat.Phys.,54(3-4),1989,829-857],the authors will first give a formal asymptotic analysis to see that the flow governed by the Boltzmann equation is accurately approximated by a superposition of a steady CNS equation with a temperature jump condition and two Knudsen layers located at end points.Then they will establish a uniform L∞estimate on the remainder and derive the slip boundary condition for compressible Navier-Stokes equations rigorously.