一类Stancu型的Szász-Mirakjan-Durrmeyer算子的逼近性质研究

该文介绍了一类Stancu型的Szász-Mirakjan-Durrmeyer算子,计算了该算子的一阶到四阶矩.然后用连续模和K-泛函等工具,讨论了该算子的逼近性质,还研究了算子对Lipschitz函数类的估计.最后建立了该算子的Voronvskaya型渐近展开式.所得定理扩展了Aslan(2022)的结果.

基于GaAs E/D PHEMT工艺的Ku波段双通道幅相控制多功能芯片

基于GaAs增强/耗尽型赝配高电子迁移率晶体管(E/D PHEMT)工艺设计了一款14~18 GHz的双通道多功能芯片。芯片集成了单刀双掷(SPDT)开关、6 bit数控移相器、4 bit数控衰减器和增益补偿放大器。采用正压控制开关以减小控制位数;优化移相、衰减和放大等电路拓扑结构,以获得良好的幅相特性;采用紧凑布局、双通道对称的版图设计,以实现小尺寸和高性能。测试结果表明,+5 V电压下,接收通道增益大于3 dB,1 dB压缩点输出功率大于8 dBm;发射通道增益大于1 dB,1 dB压缩点输出功率大于2 dBm;64态移相均方根误差小于2.5°,16态衰减均方根误差小于0.3 dB,芯片尺寸为3.90 mm×2.25 mm。该多功能芯片可实现对射频信号幅度和相位的高精度控制,可广泛应用于微波收发模块。

YBX1 inhibits mitochondrial-mediated apoptosis in ischemic heart through the PI3K/AKT signaling pathway

Background:Myocardial infarction(MI)is associated with higher morbidity and mortality in the world,especially in cold weather.YBX1 is an RNA-binding protein that is required for pathological growth of cardiomyocyte by regulating cell growth and protein synthesis.But YBX1,as an individual RNA-binding protein,regulates cardiomyocytes through signaling cascades during myocardial infarction remain largely unexplored.Methods:In vivo,the mouse MI model was induced by ligating the left anterior descending coronary artery(LAD),and randomly divided into sham operation group,MI group,MI+YBX1 knockdown/overexpression group and MI+negative control(NC)group.The protective effect of YBX1 was verified by echocardiography and triphenyltetrazolium chloride staining.In vitro,mitochondrial-dependent apoptosis was investigated by using CCK8,TUNEL staining,reactive oxygen species(ROS)staining and JC-1 staining in hypoxic neonatal mouse cardiomyocytes(NMCMs).Results:YBX1 expression of cardiomyocytes was downregulated in a mouse model and a cellular model on the ischemic condition.Compared to mice induced by MI,YBX1 overexpression mediated by adeno-associated virus serotype 9(AAV9)vector reduced the infarcted size and improved cardiac function.Knockdown of endogenous YBX1 by shRNA partially aggravated ischemia-induced cardiac dysfunction.In hypoxic cardiomyocytes,YBX1 overexpression decreased lactic dehydrogenase(LDH)release,increased cell viability,and inhibited apoptosis by affecting the expression of apoptosis related proteins,while knockdown of endogenous YBX1 by siRNA had the opposite effect.Overexpression of YBX1 restored mitochondrial dysfunction in hypoxic NMCMs by increasing mitochondrial membrane potential and ATP content and decreasing ROS.In hypoxic NMCMs,YBX1 overexpression increased the expression of phosphorylated phosphatidylinositol 3 kinase(PI3K)/AKT,and the anti-apoptosis effect of YBX1 was eliminated t by LY294002,PI3K/AKT inhibitor.Conclusion:YBX1 protected the heart from ischemic damage by inhibiting the mitochondrial-dependent apoptosis through PI3K/AKT pathway.It is anticipated that YBX1 may serve as a novel therapeutic target for MI.

基于k-体分划的D-concurrence多体纠缠测度

对于有限维多体量子系统中的态,D-concurrence是一个重要的纠缠测度,在过去的十年中被深入探索。将D-concurrence的概念推广到k-体分划的多体量子系统,它可以度量多体量子态在k-体分划下的非经典纠缠性,并证明了纠缠测度的一些必要性质,包括在k-可分态下纠缠测度为0,在局部酉操作下不变,在局部操作和经典通信(LOCC)下不增。

柴胡皂苷D调控CaMKKβ/AMPK信号通路介导ICCs细胞自噬的机制

目的探讨柴胡皂苷D调控CaMKKβ/AMPK信号通路,在功能性消化不良中对胃肠道Cajal间质细胞(Interstitial cells of Cajal,ICCs)细胞自噬的作用及机制。方法分离大鼠原代ICCs细胞,谷氨酸刺激构建ICCs自噬模型,免疫荧光检测Ca2+水平。将原代ICCs细胞分为对照组、模型组、模型+柴胡皂苷D组、模型+CaMKKβ抑制剂组、模型+柴胡皂苷D+CaMKKβ抑制剂组。透射电镜观察自噬体超微结构,ELISA检测Ghrelin和SP的水平,免疫荧光检测Ca2+和LC-3Ⅱ的表达,Western blot检测LC-3Ⅱ/Ⅰ、CaMKKβ、p-AMPK、Drp1、MFN2、IP3R和RyR的蛋白表达水平。结果谷氨酸诱导的模型组ICCs中LC-3Ⅱ荧光表达增强。柴胡皂苷D干预可降低Ca2+浓度,降低CaMKKβ、AMPK和MFN2水平(P<0.01),增加LC-3Ⅱ/Ⅰ、IP3R、RyR、Drp1、Ghrelin和SP水平(P<0.01)。柴胡皂苷D联合CaMKKβ抑制剂STO-609干预后效果更显著。结论柴胡皂苷D可通过CaMKKβ/AMPK信号通路介导Ca2+外流,影响ICCs细胞过度自噬及胃肠动力相关因子的表达。

3D printing of poly(ethyleneimine)-functionalized Mg-Al mixed metal oxide monoliths for direct air capture of CO_(2)

Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.

Databases of 2D material-substrate interfaces and 2D charged building blocks

Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188.

Ultrathin poly(cyclocarbonate-ether)-based composite electrolyte reinforced with high-strength functional skeleton

Composite polymer electrolytes(CPEs)are considered to be the most promising to break through the performance and safety limitations of traditional lithium-ion batteries because of their excellent electrochemical and mechanical properties.Aiming at the performance limitations of the most common polyether matrix such as poly(ethylene oxide)(PEO),a novel poly(cyclocarbonate-ether)polymer matrix was prepared by in-situ thermal curing,the weaker interaction between its C=O bond and Li^(+)can promote the rapid transport of Li^(+).Adding ionic liquid and active filler LLZTO to the matrix can synergistically reduce the crystallinity of matrix and promote the dissociation of lithium salts.In addition,a 3D functional skeleton made of polyacrylonitrile(PAN)and lithium fluoride(LiF)can greatly improve the mechanical strength of polymer matrix after cold pressing,and Li F is also conducive to interface stability.The thickness of the optimal sample(VP6L/CPL)was only 25μm,and its ionic conductivity,lithium ion transference number,and electrochemical stability window were as high as 7.17×10^(-4)S cm^(-1)(25℃),0.54 and 5.4 V,respectively,while the mechanical strength reaches 6.1 MPa,which can fully inhibit the growth of lithium dendrites.The excellent electrochemical performance and mechanical strength enable the assembled Li|VP6L/CPL|Li battery to be continuously charged for over 200 h and cycled stably for more than 2300 h,and Li|VP6L/CPL|LFP battery can be stably cycled for more than 400 and 550 cycles at 1 C(40℃)and 0.5 C(25℃),respectively.

Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats

Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

Movement Function Assessment Based on Human Pose Estimation from Multi-View

Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician.

维生素K1、K2、D水平与儿童骨代谢异常的相关性分析

目的分析维生素K_(1)、K_(2)、D水平与儿童骨代谢异常的相关性。方法选取2020年8月至2023年12月在钦州市第二人民医院体检的293名儿童为研究对象,根据患骨代谢疾病情况分为病例组(128例)和对照组(165例)。比较两组血清维生素K_(1)、维生素K_(2)和维生素D水平,并分析与骨代谢异常的相关性。结果病例组维生素K_(1)、维生素K_(2)和维生素D水平低于对照组,维生素K_(1)和维生素K_(2)缺乏发生率高于对照组,差异有统计学意义(P<0.05)。骨代谢异常与维生素K_(1)、维生素K_(2)和维生素D水平均呈负相关(P<0.05)。结论骨代谢异常儿童血清维生素K_(1)、维生素K_(2)和维生素D水平偏低,骨代谢异常与维生素K_(1)、维生素K_(2)和维生素D水平呈负相关,应积极预防维生素K和维生素D缺乏。

基于PI3K/AKT/mTOR途径桔梗皂苷D对脑缺血再灌注诱导的血脑屏障的保护作用及机制研究

本研究旨在探讨桔梗皂苷D (Platycodin D,PLD)通过PI3K/AKT/mTOR途径对脑缺血再灌注诱导的血脑屏障的保护作用及机制研究。试验采用糖尿病Sprague-Dawley大鼠构建大脑中动脉闭塞模型。动物试验分组:sham组、HIR组、PLD组、3-MA组(3-甲基腺嘌呤,3-methyladenine)和PLD+3-MA组。分析各组大鼠神经功能缺损评分、脑含水量、脑梗塞体积和血脑屏障渗透性。透射电子显微镜观察血脑屏障超微结构变化和自噬。免疫印迹法分析紧密连接(Tight junction,TJ)蛋白(ZO-1、claudin-5和occludin)免疫荧光染色和蛋白质免疫印迹(Western blot,WB)法,分析自噬相关蛋白(Beclin-1、LC3B和p62)和PI3K/AKT/mTOR通路相关蛋白的表达。结果表明,PLD和自噬抑制剂3-MA治疗显著降低了脑梗死体积、脑含水量和伊文思蓝渗漏,同时增加了TJ蛋白的表达,降低了自噬相关蛋白的表达(P<0.05)。此外,PLD增加了PI3K、AKT和mTOR的磷酸化水平。PLD通过抑制自噬预防高血糖条件下,脑缺血再灌注损伤后的血脑屏障损伤,可能通过调节PI3K/AKT/mTOR信号通路来实现。

K·U·D模式下基于通感理念体验的初中音乐单元作业设计路径探究

本文根据对K·U·D模型进行概念内涵进行分析,并据此设定具体的目标导向。通过与通感理念相结合的方式丰富教学体验形式,探讨不同的体验方式类型。教学实践部分围绕创设情境活动和设计单元作业进行阐述,包括多维度定制作业框架、多感官联动体验学习、多层次协作合作交流、多角度构建评价反馈以及多视角反思作业设计。每个环节都不仅反映了对音乐教育深度的追求,也体现了争取在学生群体中实现个性化作业设计和全面发展的教育理念。

Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions

The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta.

基于k-d树的ICP算法的管道缺陷最深点自动识别研究

金属管道外表面存在凹坑、腐蚀缺陷等情况,为了准确判断管道的剩余服役寿命,提出一种基于k-d树ICP算法的油气管道缺陷最深点自动识别方法。扫描获取带有缺陷的管道点云数据,提取缺陷处至少1/3管道环向区域点云数据,建立标准圆柱件模型获取点云数据。利用ICP算法对两组点云数据进行配准,基于k-d树算法关联所有无序点云,从而加速搜索点云邻域,快速精确地识别出缺陷最深点。将该算法在天然气长输管段进行验证,以第三方专业检测机构的检测缺陷最深点数据为基准,通过计算对比发现,自动识别方法的误差率仅为0.54%,较之传统人工测量方法,测量误差率降低了3.22%,有效提高了管道外表面缺陷深度测量的准确度。

THE NONLINEAR BOUNDARY VALUE PROBLEM FOR k HOLOMORPHIC FUNCTIONS IN C^(2)

k holomorphic functions are a type of generation of holomorphic functions.In this paper,a nonlinear boundary value problem for k holomorphic functions is primarily discussed on generalized polycylinders in C^(2).The existence of the solution for the problem is studied in detail with the help of the boundary properties of Cauchy type singular integral operators with a k holomorphic kernel.Furthermore,the integral representation for the solution is obtained.

PDGFRα^(+)细胞上P2Y1-SK3通路对功能性消化不良大鼠胃肠动力的调控机制

目的探究血小板衍生生长因子受体α^(+)(PDGFRα^(+))细胞上P2Y1-小电导Ca^(2+)激活K^(+)(SK3)通道对功能性消化不良(FD)大鼠胃肠动力的影响。方法将30只SD大鼠随机分为空白组、模型组、P2Y1受体抑制剂(MRS2500)组,每组10只。除空白组外,其余两组采用多因素干预法建立FD大鼠模型。造模成功后抑制剂组予以尾静脉注射P2Y1抑制剂MRS2500,其他组不采取干预措施。处理结束后进行行为学和胃肠动力学检测;用BL-420S生物信号系统采集并分析胃肠生物电信息;取胃窦组织评估病理变化;采用免疫印迹、实时荧光定量PCR技术检测各组大鼠胃窦PDGFRα、C-kit(卡介尔间质细胞特异性指标)、P2Y1和SK3的表达情况;采用免疫荧光法检测胃窦PDGFRα和C-kit、P2Y1、SK3的组织表达和共定位情况;用钙检测试剂盒检测胃窦组织中Ca^(2+)含量变化。结果FD模型建立后,大鼠活动度、体重增长速度和进食量都显著降低,胃肠动力减弱,胃窦内PDGFRα、C-kit、P2Y1和SK3表达水平降低。MRS2500干预后,P2Y1受体抑制剂组大鼠较模型组大鼠体重增长率和进食量升高,胃肠动力减弱情况改善,PDGFRα、P2Y1和SK3表达水平进一步降低,C-kit表达水平升高,Ca^(2+)含量降低。PDGFRα与C-kit在胃窦中不存在共表达,而PDGFRα与P2Y1、SK3共表达。结论长期的饮食和情绪失调会刺激肠神经系统释放抑制性神经递质,这一过程通过PDGFRα^(+)细胞上P2Y1受体引起SK3通道的Ca^(2+)敏感性降低,在多因素刺激诱导的FD模型大鼠胃肠动力障碍中起重要作用。

Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron

The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles.

老年血液透析病人衰弱与血清瘦素及25-羟维生素D的相关性研究

目的探究老年血液透析病人血清瘦素及25-羟维生素D[25(OH)D]水平,并分析其与透析病人衰弱的相关性。方法选取2021年4月至2023年4月我院收治的150例老年血液透析病人,依据Fried表型评价病人的衰弱情况,分为非衰弱组(51例),衰弱前期组(74例)和衰弱组(25例)。比较3组一般资料、血清瘦素、25(OH)D及心功能。采用多因素Logistic回归分析老年血液透析病人衰弱的影响因素。结果3组年龄、糖尿病比例、透析龄、左室舒张末期内径,以及白蛋白、镁、IL-6、瘦素、25(OH)D水平比较,差异均有统计学意义(P<0.01)。多因素有序Logistic回归分析显示,年龄、透析龄、糖尿病、镁、IL-6、白蛋白、瘦素、25(OH)D、左室舒张末期内径是老年血液透析病人衰弱的独立影响因素(P<0.05)。结论针对白蛋白水平低、瘦素水平高、25(OH)D水平低的老年血液透析病人采取积极干预措施,有利于延缓衰弱的进展。

基于D-S证据理论的岩爆预测方法研究

为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而簇间证据用权重方式融合的组合融合规则,以减轻高冲突证据融合的不利影响.最后,将模型应用在秦岭终南山公路隧道2号竖井工程,且与经验方法对比.为了分析预测过程的不确定性和估计岩爆发生概率,采用蒙特卡洛模拟进行抽样仿真,并通过Spearman秩相关系数衡量输入指标的全局敏感性.研究结果表明:输入指标在不同的岩爆案例的影响程度差异较大且方向不同;5个岩爆案例的发生概率在40.8%~70.1%之间.该模型表现出优异的预测分类性能,可为深埋地下工程岩爆预测提供参考.