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Formation Mechanism and Binding Energy for Regular Octahedral Structure of Li_6 Cluster

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Communications in Theoretical Physics 2008年第12期50卷 1407-1410页

作者： ZHAO yan-ping LI ping gou Qing-Quan LIU Wei-Na Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The formation mechanism for the regular octahedral structure of Liscluster is proposed. The curve of the total energy versus the separation R between any two neighboring nuclei has been calculated by using the method of gou＇s modified arrangement channel quantum mechanics （MACQM）. The result shows that the curve has a minimal energy of -44.736 89 a.u. at R = 5.07a0. When R approaches infinity, the total energy of six lithium atoms has the value of -44.568 17 a.u. So the binding energy of Li6 with respect to six lithium atoms is 0.1687 a.u. Therefore, the binding energy per atom for Li6 is 0.028 12 a.u., or 0.7637 eV, which is greater than the binding energy per atom of 0.453 eV for Li2 and the binding energy per atom of 0.494 eV for Li3 calculated in our previous work. This means that the Li6 cluster may be formed in a regular octahedral structure with a greater binding energy.

关键词： Li6 cluster formation mechanism binding energy

Adaptively Enhancing Facial Expression Crucial Regions via a Local Non-local Joint Network

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Machine Intelligence Research 2024年第2期21卷 331-348页

作者： Guanghui Shi Shasha Mao Shuiping gou Dandan yan Licheng Jiao Lin Xiong School of Artificial Intelligence Xidian UniversityXi'an 710000China Applied Research Laboratory Sense TimeXi'an 710000China

Facial expression recognition(FER)is still challenging due to the small interclass discrepancy in facial expression *** view of the significance of facial crucial regions for FER,many existing studies utilize the prior information from some annotated crucial points to improve the performance of ***,it is complicated and time-consuming to manually annotate facial crucial points,especially for vast wild expression *** on this,a local non-local joint network is proposed to adaptively enhance the facial crucial regions in feature learning of FER in this *** the proposed method,two parts are constructed based on facial local and non-local information,where an ensemble of multiple local networks is proposed to extract local features corresponding to multiple facial local regions and a non-local attention network is addressed to explore the significance of each local *** particular,the attention weights obtained by the non-local network are fed into the local part to achieve interactive feedback between the facial global and local ***,the non-local weights corresponding to local regions are gradually updated and higher weights are given to more crucial ***,U-Net is employed to extract the integrated features of deep semantic information and low hierarchical detail information of expression ***,experimental results illustrate that the proposed method achieves more competitive performance than several state-of-the-art methods on five benchmark datasets.

关键词： Facial expression recognition deep neural network multiple network ensemble attention network facial crucial regions

Predictive utility of the Rockall scoring system in patients suffering from acute nonvariceal upper gastrointestinal hemorrhage

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2620-2629页

作者： De-ping Han Cai-Qian gou Xin-Mian Ren Department of Emergency Chengyang District People’s HospitalQingdao 266109Shandong ProvinceChina

BACKGROUND Acute non-variceal upper gastrointestinal bleeding(ANVUGIB)represents a sig-nificant clinical challenge due to its unpredictability and potentially severe *** Rockall risk score has emerged as a critical tool for prognostic asse-ssment in patients with ANVUGIB,aiding in the prediction of rebleeding and ***,its applicability and accuracy in the Chinese population remain *** To assess the prognostic value of the Rockall risk score in a Chinese cohort of patients with *** A retrospective analysis of 168 ANVUGIB patients’medical records was *** study employed statistical tests,including the t-test,χ2 test,spearman correlation,and receiver operating characteristic(ROC)analysis,to assess the re-lationship between the Rockall score and clinical outcomes,specifically focusing on rebleeding events within 3 months *** Significant associations were found between the Rockall score and various clinical *** Rockall scores were significantly associated with rebleeding events(r=0.735,R2=0.541,P<0.001)and strongly positively correlated with adverse *** hemoglobin levels(t=2.843,P=0.005),high international normalized ratio(t=3.710,P<0.001),active bleeding during endoscopy(χ2=7.950,P=0.005),large ulcer size(t=6.348,P<0.001),and requiring blood transfusion(χ2=6.381,P=0.012)were all significantly associated with rebleeding ***,differences in treatment and management strategies were identified between patients with and without rebleeding *** analysis indicated the excellent discriminative power(sensitivity:0.914;specificity:0.816;area under the curve:0.933;Youden index:0.730)of the Rockall score in predicting rebleeding events within 3 *** This study provides valuable insights into the prognostic value of the Rockall risk score for ANVUGIB in the Chinese *** results underscore the potential of the Rockall score as an effective tool

关键词： Acute non-variceal upper gastrointestinal bleeding Rockall risk score Clinical outcomes Risk stratification Prognosis

Channel assignment and power allocation for throughput improvement with PPO in B5G heterogeneous edge networks

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Digital Communications and Networks 2024年第1期10卷 109-116页

作者： Xiaoming He Yingchi Mao Yinqiu Liu ping ping yan Hong Han Hu The College of Computer and Information Hohai UniversityNanjingChina The Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing China The School of Computer Science and Engineering Nanyang Technological UniversitySingapore The College of Textile and Clothing Engineering Soochow UniversitySuzhouChina The College of Internet of Things Nanjing University of Posts and TelecomurunicationsNanjingChina

In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver uses interference ***,uncoordinated radio resource allocation can reduce system throughput and lead to user inequity,for this reason,in this paper,channel allocation and power allocation problems are formulated to maximize the system sum rate and minimum user achievable *** the construction model is non-convex and the response variables are high-dimensional,a distributed Deep Reinforcement Learning(DRL)framework called distributed Proximal Policy Optimization(PPO)is proposed to allocate or assign ***,several simulated agents are trained in a heterogeneous environment to find robust behaviors that perform well in channel assignment and power ***,agents in the collection stage slow down,which hinders the learning of other ***,a preemption strategy is further proposed in this paper to optimize the distributed PPO,form DP-PPO and successfully mitigate the straggler *** experimental results show that our mechanism named DP-PPO improves the performance over other DRL methods.

关键词： B5G Heterogeneous edge networks PPO Channel assignment Power allocation Throughput

Membrane vesicles derived from Streptococcus suis serotype 2 induce cell pyroptosis in endothelial cells via the NLRP3/Caspase-1/GSDMD pathway

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Journal of Integrative Agriculture 2024年第4期23卷 1338-1353页

作者： Keda Shi yan Li Minsheng Xu Kunli Zhang Hongchao gou Chunling Li Shaolun Zhai Institute of Animal Health Guangdong Academy of Agricultural Sciences/Key Laboratory of Livestock Disease Prevention ofGuangdong Province/Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of GuangdongProvinceMinistry of Agriculture and Rural AffairsGuangzhou 510640China Maoming Branch Guangdong Laboratory for Lingnan Modern Agricultural Science and TechnologyMaoming 525000China College of Animal Science&Technology Zhongkai University of Agriculture and EngineeringGuangzhou 510225China

Streptococcus suis serotype 2(*** 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different organs,*** 2 must colonize the host,break the blood barrier,and cause exaggerated *** the last few years,most studies have focused on a single virulence factor and its influences on the *** vesicles(MVs)can be actively secreted into the extracellular environment contributing to bacteria-host ***-negative bacteria-derived outer membrane vesicles(OMVs)were recently shown to activate host Caspase-11-mediated non-canonical inflammasome pathway via deliverance of OMV-bound lipopolysaccharide(LPS),causing host cell ***,little is known about the effect of the MVs from *** 2(Gram-positive bacteria without LPS)on cell ***,we investigated the molecular mechanism by which *** 2 MVs participate in endothelial cell *** this study,we used proteomics,electron scanning microscopy,fluorescence microscope,Western blotting,and bioassays,to investigate the MVs secreted by *** ***,we demonstrated that *** 2 secreted MVs with an average diameter of 72.04 nm,and 200 proteins in MVs were ***,we showed that MVs were transported to cells via mainly dynamin-dependent *** *** 2 MVs activated NLRP3/Caspase-1/GSDMD canonical inflammasome signaling pathway,resulting in cell pyroptosis,but it did not activate the Caspase-4/-5 *** importantly,endothelial cells produce large amounts of reactive oxygen species(ROS)and lost their mitochondrial membrane potential under induction by *** 2 *** results in this study suggest for the first time that MVs from *** 2 were internalized by endothelial cells via mainly dynamin-dependent endocytosis and might promote NLRP3/Caspase-1/GSDMD pathway by mitochondrial damage,which produced mtDNA and ROS under induction,

关键词： Streptococcus suis serotype 2 membrane vesicles endocytosis pyroptosis NLRP3 inflammasomes mitochondrial damage endothelial cell

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： yan yan Guang-hao Shang Li-ping Zhang Shao-ying Li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

Spherical Confinement Generates Entropic Force to Accelerate Polymer Chain Detachment

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Chinese Journal of Polymer Science 2024年第3期42卷 407-416,I0010页

作者： Yu-Shan Zheng Jian-ping Zhou yan Xu Kai Li Mechanical Engineering Xinjiang UniversityUrumqi 830002China

To understand the dynamic process of polymer detachment, it is necessary to determine the mean detachment time of a single breakable link, which is modeled as a spring. Normally, this time can be viewed as the escape of a Brownian particle from the potential well of the spring. However, as the free dangling length of the polymer chain increases, the conformational entropy of the chain is affected by geometric confinement. It means that the wall exerts a repulsive force on the chain, resulting in accelerated link detachment from a macroscopic perspective. In this work, we investigate the effect of entropy on the detachment rate in the case where the substrate is spherical. We demonstrate that spherical confinement accelerates chain detachment both inside and outside the sphere. An analytical expression for the mean detachment time of breakable links is given, which includes an additional pre-factor that is related to the partition function. Additionally, we analyze the expressions for entropic forces inside the sphere, outside the sphere, and on a flat wall, comparing their magnitudes to explain the difference in mean detachment time.

关键词： Polymer detachment Breakable link Entropic force Mean first passage time

A low-profile metamaterial absorber with ultrawideband reflectionless and wide-angular stability

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Defence Technology（防务技术） 2024年第4期34卷 258-268页

作者： Feihong Lin Zhongming yan ping Wang Yu Wang Hongcheng Zhou Haoran Lu School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle Ministry of EducationChengdu 610031China China Academy of Launch Vehicle Technology Beijing 100076China

An ultrawideband reflectionless metamaterial absorber(MA)is proposed by replacing the metallic ground with the complementary split-ring resonator(CSRR)*** proposed MA exhibits-10 d B reflectivity spectrum from 1 GHz to 20 GHz,which maintains more than 90%absorption from 1.5 GHz to20 ***,it achieves angle stability for TE and TM polarization at oblique incident angles up to 40°and 65°,*** achieve broadband absorption spectrum,we have adopted a single-layer high-impedance surface(HIS)loaded with a double-layer magnetic material(MM)*** further realize the RCS reduction into a lower frequency range,we have employed the scattering cancellation technology into the traditional metallic ***,we have fabricated a sample exhibiting the 10 d B RCS reduction from 1 GHz to 20 GHz with a thickness of 10 *** and simulation results confirm that the proposed MA exhibits excellent comprehensive performance,making it suitable for many practical applications.

关键词： Metamaterial absorber(MA) Magnetic material(MM) High-impedance surface(HIS) Scattering cancellation technology Ultrawideband Wide-angular stable

Solving the subset sum problem by the quantum Ising model with variational quantum optimization based on conditional values at risk

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 43-55页

作者： Qilin Zheng Miaomiao Yu pingyu Zhu yan Wang Weihong Luo ping Xu Institute for Quantum Information and State Key Laboratory of High Performance Computing College of Computer Science and TechnologyNational University of Defense TechnologyChangsha 410073China Hefei National Laboratory Hefei 230088China

The subset sum problem is a combinatorial optimization problem,and its complexity belongs to the nondeterministic polynomial time complete(NP-Complete)*** problem is widely used in encryption,planning or scheduling,and integer *** accurate search algorithm with polynomial time complexity has not been found,which makes it challenging to be solved on classical *** effectively solve this problem,we translate it into the quantum Ising model and solve it with a variational quantum optimization method based on conditional values at *** proposed model needs only n qubits to encode 2ndimensional search space,which can effectively save the encoding quantum *** model inherits the advantages of variational quantum algorithms and can obtain good performance at shallow circuit depths while being robust to noise,and it is convenient to be deployed in the Noisy Intermediate Scale Quantum *** investigate the effects of the scalability,the variational ansatz type,the variational depth,and noise on the ***,we also discuss the performance of the model under different conditional values at *** computer simulation,the scale can reach more than nine *** selecting the noise type,we construct simulators with different QVs and study the performance of the model with *** addition,we deploy the model on a superconducting quantum computer of the Origin Quantum Technology Company and successfully solve the subset sum *** model provides a new perspective for solving the subset sum problem.

关键词： subset sum problem quantum Ising model conditional values at risk variational quantum optimization

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