A Constrained Local Neighborhood Approach for Efficient Markov Blanket Discovery in Undirected Independent Graphs

When learning the structure of a Bayesian network,the search space expands significantly as the network size and the number of nodes increase,leading to a noticeable decrease in algorithm efficiency.Traditional constraint-based methods typically rely on the results of conditional independence tests.However,excessive reliance on these test results can lead to a series of problems,including increased computational complexity and inaccurate results,especially when dealing with large-scale networks where performance bottlenecks are particularly evident.To overcome these challenges,we propose a Markov blanket discovery algorithm based on constrained local neighborhoods for constructing undirected independence graphs.This method uses the Markov blanket discovery algorithm to refine the constraints in the initial search space,sets an appropriate constraint radius,thereby reducing the initial computational cost of the algorithm and effectively narrowing the initial solution range.Specifically,the method first determines the local neighborhood space to limit the search range,thereby reducing the number of possible graph structures that need to be considered.This process not only improves the accuracy of the search space constraints but also significantly reduces the number of conditional independence tests.By performing conditional independence tests within the local neighborhood of each node,the method avoids comprehensive tests across the entire network,greatly reducing computational complexity.At the same time,the setting of the constraint radius further improves computational efficiency while ensuring accuracy.Compared to other algorithms,this method can quickly and efficiently construct undirected independence graphs while maintaining high accuracy.Experimental simulation results show that,this method has significant advantages in obtaining the structure of undirected independence graphs,not only maintaining an accuracy of over 96%but also reducing the number of conditional independence tests by at least 50%.This significant performance improvement is due to the effective constraint on the search space and the fine control of computational costs.

Propofol and remifentanil at moderate and high concentrations affect proliferation and differentiation of neural stem/progenitor cells

Propofol and remifentanil alter intracellular Ca^2＋ concentration （[Ca^2＋]i） in neural stem/progen-itor cells by activating γ-aminobutyric acid type A receptors and by reducing testosterone levels. However, whether this process affects neural stem/progenitor cell proliferation and differenti-ation remains unknown. In the present study, we applied propofol and remifentanil, alone or in combination, at low, moderate or high concentrations （1, 2–2.5 and 4–5 times the clinically effective blood drug concentration）, to neural stem/progenitor cells from the hippocampi of newborn rat pups. Low concentrations of propofol, remifentanil or both had no noticeable effect on cell proliferation or differentiation; however, moderate and high concentrations of propofol and/or remifentanil markedly suppressed neural stem/progenitor cell proliferation and differen-tiation, and induced a decrease in [Ca^2＋]i during the initial stage of neural stem/progenitor cell differentiation. We therefore propose that propofol and remifentanil interfere with the prolifer-ation and differentiation of neural stem/progenitor cells by altering [Ca^2＋]i. Our ifndings suggest that propofol and/or remifentanil should be used with caution in pediatric anesthesia.

Secrecy Transmission of NOMA-OTFS Based Multicast-Unicast Streaming

This paper investigates the security performance of a cooperative multicast-unicast system,where the users present the feature of high mobility.Specifically,we develop the non-orthogonal multiple access(NOMA)based orthogonal time frequency space(OTFS)transmission scheme,namely NOMAOTFS,in order to combat Doppler effect as well as to improve the spectral efficiency.Further,we propose a power allocation method addressing the trade-off between the reliability of multicast streaming and the confidentiality of unicast streaming.Based on that,we utilize the relay selection strategy,to improve the security of unicast streaming.In the context of multicastunicast streaming,our simulation findings validate the effectiveness of the NOMA-OTFS based cooperative transmission,which can significantly outperform the existing NOMA-OFDM in terms of both reliability and security.

N-methyl-D-aspartate receptor effects on p38 mitogen activated protein kinase and its role in a rat model of diabetic neuropathic pain

BACKGROUND： Activated N-methyl-D-aspartate （NMDA） receptor is involved in the formation of chronic neuropathic pain, and its antagonist, ketamine, exhibits effective amelioration of diabetic neuropathic pain （DNP）. However, the mechanisms of NMDA receptor participation in the formation and maintenance of DNP remain poorly understood. OBJECTIVE： To evaluate the role NMDA receptor plays in DNP and effects on p38 mitogen activated protein kinase （p38 MAPK） in a rat model of DNP. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Human Embryonic Stem Cell Research Institute of Yunyang Medical College Affiliated Taihe Hospital between July 2005 and September 2007. MATERIALS： Streptozotocin was provided by Sigma, USA; p38 MAPK inhibitor （SB203580） was provided by Shanghai KangChen Biotech, China; NMDA receptor antagonist （MK-801） was purchased from Shanghai Yope Biotech, China. METHODS： A total of 128 healthy, Wistar rats of clean grade, aged 3 months and weighing 180- 220 g, were randomly assigned to 4 groups： control, DNP model, p38 MAPK, and NMDA receptor. Each group contained 32 rats. DNP was established in all groups except for the control group by intraperitoneal injection of streptozocin （65 mg/kg）. Subsequently, 1 mg/kg SB203580 and 1 mg/kg MK-801 were injected once each week via intraperitoneal injection in the p38 MAPK and NMDA receptor groups, respectively. MAIN OUTCOME MEASURES： At the end of 2, 4, 6, and 8 weeks following streptozotocin injection, mechanical withdrawal threshold was measured in 8 animals from each group following von Frey filament stimulation. The rats were anesthetized and nerve conduction velocity of the left sciatic nerve was measured. Subsequently, the right sciatic nerve, the lumbar segment of the spinal cord, and dorsal root ganglia were removed from the L3-6 segment for microscopic examination, p38 MAPK expression was determined using immunohistochemistry and Western blot analysis. Expression of NMDA receptor 1 mRNA in dorsal root ganglion and spinal cord neurons was detected using RT-PCR. RESULTS： Mechanical withdrawal threshold and nerve conduction velocity were significantly reduced, and p38 MAPK and NMDA receptor 1 mRNA expression in the spinal cord and dorsal root ganglia were significantly increased, in the model, p38 MAPK, and NMDA receptor groups compared with the control group at all time points （P 〈 0.05）. At 4-8 weeks following successful DNP model establishment, SB203580 and MK-801 increased mechanical withdrawal threshold, accelerated nerve conduction velocity, and attenuated p38 MAPK expression, compared with the model group. The NMDA receptor group exhibited downregulated mRNA expression of NMDA receptor 1 compared with the model and p38 MAPK groups （P 〈 0.05）. CONCLUSION： NMDA receptor was highly expressed in the brains of DNP rats and was involved in DNP development via activation of the p38 MAPK signal pathway.

Study on the Pollen Thermo-Sensitive and Stigma Exsertion Male Sterile Line Tomato (Lycopersicon esculentum Mill.) cv. Da107

To accelerate the breeding process, male sterile line is used to leave out the troublesome procedures of the artificial emasculation in tomato breeding. However, the fertility of the pollen thermo-sensitivity male sterile line (PTMSL) and the stigma exsertion male sterile line (SEMSL) are affected easily by the environments when used alone. The trial materials were Da107 and the control was First. This study was conducted to create a new male sterile line of tomato characterized by pollen thermo-sensitivity and long style by genic recombination through the hybridizing of the PTMSL and SEMSL. Research on the statistics of the pollen germination rate, the contamination rate in F1 and the flower organics indicated that Da107 was an ideal TS and SE male sterile line with the sterility of 95%, as well as it also could be used as fertile line at low temperature. Meanwhile, the results showed that hybrid-seed contamination risk with selfed seeds from residual fertility in Da107 was low.

Self-Awakened Particle Swarm Optimization BN Structure Learning Algorithm Based on Search Space Constraint

To obtain the optimal Bayesian network(BN)structure,researchers often use the hybrid learning algorithm that combines the constraint-based(CB)method and the score-and-search(SS)method.This hybrid method has the problemthat the search efficiency could be improved due to the ample search space.The search process quickly falls into the local optimal solution,unable to obtain the global optimal.Based on this,the Particle SwarmOptimization(PSO)algorithm based on the search space constraint process is proposed.In the first stage,the method uses dynamic adjustment factors to constrain the structure search space and enrich the diversity of the initial particles.In the second stage,the update mechanism is redefined,so that each step of the update process is consistent with the current structure which forms a one-to-one correspondence.At the same time,the“self-awakened”mechanism is added to prevent precocious particles frombeing part of the best.After the fitness value of the particle converges prematurely,the activation operation makes the particles jump out of the local optimal values to prevent the algorithmfromconverging too quickly into the local optimum.Finally,the standard network dataset was compared with other algorithms.The experimental results showed that the algorithmcould find the optimal solution at a small number of iterations and a more accurate network structure to verify the algorithm’s effectiveness.

全固态双Z型异质结光催化剂的研究进展

光催化技术在解决能源和环境问题方面展现出巨大的潜力.但由于可见光利用率低、载流子复合率高、氧化还原能力差等因素导致单组分半导体的光催化活性不尽人意.因此,开发有效的策略来提高半导体的光催化活性成为光催化技术应用的关键.通过构筑双Z型异质结可以延长载流子寿命,拓宽光吸收范围,提高光生载流子浓度,增大氧化还原电位.同时,双Z型异质结具有多个电子转移通道,更有利于光诱导电子迁移,促进电子–空穴对的有效分离.近年来双Z型异质结得到了快速发展,双Z型光催化剂的理论体系也比较成熟.然而,目前系统总结双Z型异质结光催化剂的综述还较少.本文详细介绍了二元异质结和双Z型异质结的种类,总结了双Z型异质结在提高光催化效率方面的优势,重点介绍了验证双Z型异质结方法,全面讨论了双Z型异质结在污染物处理、分解水产氢、CO_(2)还原、光催化固氮、细胞失活等方面的应用,展望了双Z型异质结光催化剂面临的挑战和未来可能的发展方向.本文的研究将为开发设计更高效的双Z型异质结提供有益的参考.

基于杂多钒酸盐扩展结构——新型多钒硼酸盐材料化学研究进展

多钒硼酸盐(VBOs)是一类结合了钒酸盐和硼酸盐结构特点的新型多金属氧酸盐(POMs),其分子内部既包含V–O基团又包含B–O基团.鉴于钒氧间可形成[VO_(6)]八面体、[VO_(5)]四角方锥和[VO_(4)]四面体等配位单元,硼氧间可形成[BO4]四面体、[BO_(3)]平面三角形及其派生的众多结构类型,两者通过多面体间的共顶点、共棱或共面的连接方式,可得到丰富多彩的VBOs拓扑结构.近年来,VBOs因其结构的多样性和钒的价态的可变性在催化、磁性、非线性光学、电子导体和锂电池等领域有着潜在的应用前景.本文主要综述了本课题组及国内外相关课题组在新型VBOs的结构设计与性能研究方面的新进展,根据[VxBy]n-基本构筑单元的不同分类归纳了该系列化合物的相关结构,阐述了部分代表性化合物的结构特点及合成策略,整理了该类化合物的功能应用,并对VBOs材料的未来发展趋势进行了展望.

PM6:Y6基三元有机太阳能电池研究进展

有机太阳能电池(OSCs)因具有质轻、柔性、可印刷制备等优点受到广泛的关注.近年来,由于新型给受体材料的研发, OSCs的能量转换效率已经有了很大的突破.特别是基于宽带隙聚合物PM6和新型非富勒烯受体Y6构筑的二元OSCs的效率高达15.7%,这使得PM6:Y6基OSCs成为研究热点.由于二元OSCs的活性层对太阳光谱的吸收相对有限,限制了器件性能的进一步提升.通过引入吸收互补的第三组分构建三元OSCs被证明是提高器件性能的一种非常有效的策略.基于三元策略, PM6:Y6基OSCs的效率得到了大幅提升.因此,有必要全面总结PM6:Y6基三元OSCs的研究进展.本文介绍了三元OSCs的工作机制,探究了第三组分的作用和选取依据,重点综述了聚合物给体、小分子给体、富勒烯受体、非富勒烯受体作为第三组分构筑的PM6:Y6基OSCs的研究进展,并对未来PM6:Y6基三元OSCs的发展进行了展望.

基于纳米金核酸探针的新型试纸条对灿烂弧菌快速检测

灿烂弧菌Vibrio splendidus作为一种水产条件致病菌,可以感染多种水产养殖动物,给水产养殖业带来巨大的经济损失。文中将核酸外切酶Ⅲ酶切信号放大策略和纳米金标记DNA探针核酸试纸条相结合,建立了一种新型高效的灿烂弧菌检测方法,检测结果可凭肉眼直接判定,并突破了常规免疫试纸条单克隆抗体制备困难的障碍。经过实验条件优化,该核酸试纸条对灿烂弧菌人工合成寡核苷酸DNA片段的检测限是5ng/mL,对灿烂弧菌基因组DNA实际样本的检测限是10ng/mL,较PCR法灵敏度高,并对灿烂弧菌具有检测特异性。研究结果实现了核酸试纸条的快捷制备及对灿烂弧菌的高效检测,为水产病害的防治开辟了新的途径。

A rapid method for validation and visualization of agile Earth-observation satellites scheduling

This paper describes a rapid method for validation and visualization of agile Earth-observation satellites scheduling.Benefited from the previous work,various algorithms are proposed for scheduling the observations of agile satellites.However,the satellite maneuvers are three-dimensional,this characteristic makes it difficult for the operation engineers to validate and interpret the scheduled solutions.They have to plot these attitude data to analyze different situations such as an observing phase or a slew maneuver.Finally,one tries to imagine the three-dimensional situations from many one-dimensional plots,which is time-consuming and susceptible to errors.Moreover,now it is low-efficiency to deal with the data about ephemeris,targets,etc.,because different software platforms are required.In this research,a validation and visualization method is suggested to overcome this barrier.It is successful to integrate the Satellite Tool Kit ActiveX and the C#programming language.Based on the embedded scheme,all the interaction and assessment can be visualized.Practical techniques for modelling satellite objects,sensor objects,target objects and satellite attitudes are presented.Such a method has been applied for Chinese agile satellites project,and a software interface has been developed.The simulation results indicate that the proposed method is intuitive and efficient.Note that this method is general,and thus it can be applied to other Earth observation missions.Enough details are provided for interested readers to develop the software interface.

Monitoring the levels of brominated and organophosphate flame retardants in passenger cars:Utilisation of car air filters as active samplers

Filters in residential and office air conditioning(A/C)systems have been used as sampling devices for monitoring different pollutants.However,cabin air filters(CAFs)in the A/C system of passenger cars have not been utilised for this purpose.In this study,we collected22 used CAFs from passenger cars in Hanoi,Vietnam to analyse for 8 polybrominated diphenyl ethers(PBDEs)and 10 organophosphate esters(OPEs).All the analytes were detected in more than 50%of samples with the exception of BDE153 and BDE154.The average concentrations of∑10OPEs and∑8 BDEs in the captured dust were 2600 and 40 ng/g,respectively with Tris(1-chloro-2-propyl)phosphate(TCIPP)and BDE209 as the dominant congener in OPE and BDE groups,respectively.CAFs are a potential tool to qualitatively assess the levels of semi-volatile chemicals in suspended dust in cars as a screening step for exposure assessment of those chemicals.