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Topology Optimization of Truss-Like Structure with Stress Constraints Under Multiple-Load Cases

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Acta Mechanica Solida Sinica 2020年第2期33卷 226-238页

作者： Hao cui Kemin zhou College of Civil Engineering Huaqiao UniversityNo.668 Jimei AvenueXiamen 361021FujianChina

A new method for topology optimization of truss-like structures with stress constraints under multiple-load cases(MLCs)is presented.A spatial truss-like material model with three families of orthotropic members is adopted,in which the three families of members along three orthotropic directions are embedded continuously in a weak matrix.The densities and directions of the three families of members at the nodes are taken as the design variables.An optimality criterion is suggested based on the concept of directional stiffness.First,under each single-load case(SLC),the truss-like structure is optimized as per the fully stressed criterion.Accordingly,the directional stiffness of the optimal structure under an SLC at every node is obtained.Next,the directional stiffness of the truss-like structure under MLCs is determined by ensuring that the directional stiffness is as similar as possible to the maximum directional stiffness of the optimal structure under every SLC along all directions.Finally,the directions and densities of the members in the optimal truss-like structures under MLCs are obtained by solving the eigenvalue problems of the coefficient matrix of the directional stiffness at every node.Two examples are presented to demonstrate the effectiveness and efficiency of the method.

关键词： Topology optimization Truss-like structure Stress constraints Multiple-load cases Eigenvalue problem

Asymmetric reconstruction of the aquareovirus core at near-atomic resolution and mechanism of transcription initiation

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Protein & Cell 2023年第7期14卷 546-550页

作者： Alexander Stevens Yanxiang cui Sakar Shivakoti Hong zhou Department of Microbiology Immunology and Molecular GeneticsUniversity of CalifomiaLos Angeles(UCLA)609 Charles E Young Dr ELos AngelesCA 90095USA California NanoSystems Institute UCLA570 Westwood Plaza Building 114/Mail Code:722710Los AngelesCA 90095USA Department of Chemistry and Biochemistry UCLA607 Charles E.Young Drive East|Box 951569Los AngelesCA 90095-1569USA

Dear Editor,Aquareovirus(ARV,Reoviridae)causes hemorrhagic disease in the economically important golden shiner and grass carp of America and China,respectively(Nason et al.,2000;Fang et al.,2005).Reoviridae members are characterized by endogenous transcription of their multipartite genomes within capsids of 1-3 layers and are further classified based on the presence(Spinareovirinae subfamily,9 genera)or absence(Sedoreovirinae subfamily,6 genera)of mRNA-capping turrets along the innermost layer(King et al.,2012).

关键词： mechanism endogenous reovirus

Universal dynamic scaling and Contact dynamics in quenched quantum gases

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Frontiers of physics 2024年第2期19卷 213-220页

作者： Jia-Nan cui Zhengqiang zhou Mingyuan Sun School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Recently universal dynamic scaling is observed in several systems,which exhibit a spatiotemporal self-similar scaling behavior,analogous to the spatial scaling near phase transition.The latter one arises from the emergent continuous scaling symmetry.Motivated by this,we investigate the possible relation between the scaling dynamics and the continuous scaling symmetry in this paper.We derive a theorem that the scaling invariance of the quenched Hamiltonian and the initial density matrix can lead to the universal dynamic scaling.It is further demonstrated both in a two-body system analytically and in a many-body system numerically.For the latter one,we calculate the dynamics of quantum gases quenched from the zero interaction to a finite interaction via the non-equilibrium high-temperature virial expansion.A dynamic scaling of the momentum distribution appears in certain momentum-time windows at unitarity as well as in the weak interacting limit.Remarkably,this universal scaling dynamics persists approximately with smaller scaling exponents even if the scaling symmetry is fairly broken.Our findings may offer a new perspective to interpret the related experiments.We also study the Contact dynamics in the BEC−BCS crossover.Surprisingly,the half-way time displays a maximum near unitarity while some damping oscillations occur on the BEC side due to the dimer state,which can be used to detect possible two-body bound states in experiments.

关键词： dynamic scaling Contact dynamics quantum gases cold atom quench dynamics virial expansion continuous scaling symmetry

Comparative Analysis of Human Genes Frequently and Occasionally Regulated by m^6A Modification

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Genomics, Proteomics & Bioinformatics 2018年第2期16卷 127-135页

作者： Yuan zhou Qinghua cui Department of Biomedical Informatics School of Basic Medical Sciences Peking University

The m^6A modification has been implicated as an important epitranscriptomic marker, which plays extensive roles in the regulation of transcript stability, splicing, translation, and localization. Nevertheless, only some genes are repeatedly modified across various conditions and the principle of m^6A regulation remains elusive. In this study, we performed a systems-level analysis of human genes frequently regulated by m^6A modification （m^6Afreq genes） and those occasionally regulated by m^6A modification （m^6Aocca genes）. Compared to the m^6Aocca genes, the m^6Afreq genes exhibit gene importance-related features, such as lower dN/dS ratio, higher protein-protein interaction network degree, and reduced tissue expression specificity. Signaling network analysis indicates that the m^6Afreq genes are associated with downstream components of signaling cascades, high-linked signaling adaptors, and specific network motifs like incoherent feed forward loops. Moreover, functional enrichment analysis indicates significant overlaps between the m^6Afreq genes and genes involved in various layers of gene expression, such as being the microRNA targets and the regulators of RNA processing. Therefore, our findings suggest the potential interplay between m^6A epitranscriptomic regulation and other gene expression regulatory machineries.

关键词： m^6A Epitranscriptome Signaling network Gene expression regulation Gene importance

Five trends of China's pharmaceutical industry in 2022

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药学学报:英文版 2023年第6期13卷 2812-2814页

作者： Yue Chen Jianing Song Yihang cui Liyun zhou Pharmcube(Beijing)Co. Ltd.Beijing 100020China Dongzhimen Hospital Beijing University of Chinese MedicineBeijing 100700China

In recent years, China has started to encourage pharmaceutical enterprises to carry out research and development of innovative drugs.From 2018 to 2021, with the capital rapidly influx into the pharmaceutical industry, there were increasing numbers of financing events with growing amount year by year1. The rapid development of China's pharmaceutical industry in the past five years is also accompanied by bubbles.

关键词： enterprises industry carry

Expert opinion on translational research for advanced glioblastoma treatment

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Cancer Biology & Medicine 2023年第5期20卷 344-352页

作者： Xiaoteng cui Yunfei Wang Junhu zhou Qixue Wang Chunsheng Kang Laboratory of Neuro-oncology Tianjin Neurological InstituteKey Laboratory of Post-Neuro Injury Neuro-Repair and Regeneration in Central Nervous SystemMinistry of Education and Tianjin CityTianjin Medical University General HospitalTianjin 300052China

Malignant gliomas are known to be one of the most difficult diseases to diagnose and treat because of the infiltrative growth pattern,rapid progression,and poor prognosis.Many antitumor drugs are not ideal for the treatment of gliomas due to the blood-brain barrier.Temozolomide(TMZ)is a DNA alkylating agent that can cross the blood-brain barrier.As the only first-line chemotherapeutic drug for malignant gliomas at present,TMZ is widely utilized to provide a survival benefit;however,some patients are inherently insensitive to TMZ.In addition,patients could develop acquired resistance during TMZ treatment,which limits antitumor efficacy.To clarify the mechanism underlying TMZ resistance,numerous studies have provided multilevel solutions,such as improving the effective concentration of TMZ in tumors and developing novel small molecule drugs.This review discusses the in-depth mechanisms underlying TMZ drug resistance,thus aiming to provide possibilities for the establishment of personalized therapeutic strategies against malignant gliomas and the accelerated development and transformation of new targeted drugs.

关键词： Malignant gliomas glioblastoma temozolomide chemoresistance small molecule drugs

Algorithms and statistical analysis for linear structured weighted total least squares problem

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Geodesy and Geodynamics 2024年第2期15卷 177-188页

作者： Jian Xie Tianwei Qiu cui zhou Dongfang Lin Sichun Long School of Earth Science and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Science Central South University of Forestry and TechnologyChangsha 410018China National-Local Joint Engineering Laboratory of Geo-spatial Information Technology Hunan University of Science and TechnologyXiangtan 411201China

Weighted total least squares(WTLS)have been regarded as the standard tool for the errors-in-variables(EIV)model in which all the elements in the observation vector and the coefficient matrix are contaminated with random errors.However,in many geodetic applications,some elements are error-free and some random observations appear repeatedly in different positions in the augmented coefficient matrix.It is called the linear structured EIV(LSEIV)model.Two kinds of methods are proposed for the LSEIV model from functional and stochastic modifications.On the one hand,the functional part of the LSEIV model is modified into the errors-in-observations(EIO)model.On the other hand,the stochastic model is modified by applying the Moore-Penrose inverse of the cofactor matrix.The algorithms are derived through the Lagrange multipliers method and linear approximation.The estimation principles and iterative formula of the parameters are proven to be consistent.The first-order approximate variance-covariance matrix(VCM)of the parameters is also derived.A numerical example is given to compare the performances of our proposed three algorithms with the STLS approach.Afterwards,the least squares(LS),total least squares(TLS)and linear structured weighted total least squares(LSWTLS)solutions are compared and the accuracy evaluation formula is proven to be feasible and effective.Finally,the LSWTLS is applied to the field of deformation analysis,which yields a better result than the traditional LS and TLS estimations.

关键词： Linear structured weighted total least squares Errors-in-variables Errors-in-observations Functional modelmodification Stochastic model modification Accuracyevaluation

Efficacy of Sitagliptin on Nonalcoholic Fatty Liver Disease in High-fat-diet-fed Diabetic Mice

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Current Medical Science 2022年第3期42卷 513-519页

作者： Shu-tong zhou Wen cui Li KONG Xun YANG Department of Gastroenterology Beijing Friendship HospitalCapital Medical UniversityBeijing100050China Department of Cardiology Fuwai HospitalChinese Academy of Medical SciencesBeijing 100037China Department of Quality Management Zhumadian Central HospitalHuanghuai UniversityZhumadian 463000China

Objective Nonalcoholic fatty liver disease(NAFLD)is a common cause of clinical liver dysfunction and an important prepathological change of liver cirrhosis.Central obesity,type 2 diabetes mellitus,dyslipidemia,and metabolic syndrome are the major risk factors for NAFLD.Sitagliptin(Sig)is a novel hypoglycemic agent that improves blood glucose levels by increasing the level of active incretin.Sig has been shown to prevent the development of fatty livers in mice on a fructose-rich diet.The purpose of this study was to observe the efficacy of Sig on NAFLD in type 2 diabetic mice.Methods The diet-induced obesity mouse model was established,and the diabetic mice were screened by an intraperitoneal glucose tolerance trial.The mice were randomly divided into four groups for 8 weeks of intervention:high-fat diet(HFD)group,Sig group,metformin(Met)group,and Sig+Met group.After the intervention,the liver function indexes as well as the blood glucose and blood lipid levels of the mice were measured.In addition,the wet weight of the liver was measured;the pathological sections of the liver tissues were stained to observe the hepatocyte fatty degeneration,inflammation,necrosis,and fibrosis;and the hepatic histological injury was recorded as the NAFLD activity score(NAS).Results Compared with the normal control group,the body weight,liver weight,blood glucose level,insulin resistance(IR),blood lipid level,and transaminase level of the mice in the HFD group were significantly increased,showing typical metabolic syndrome.After treatment with Sig and/or Met,the mice gained less weight,had lower levels of blood glucose,triglyceride(TG),low-density lipoprotein cholesterol(LDL-C),and transaminase,and had improved IR compared with the HFD group.The liver pathological NASs in the Sig group(P=0.01),Met group(P=0.028),and Sig+Met group(P<0.001)were lower than those in the HFD group(P<0.05),suggesting that the use of the two drugs alone or in combination can improve the state of liver inflammation.In terms of fibrosis,there was no fibrosis

关键词： nonalcoholic fatty liver disease sitagliptin insulin resistance nonalcoholic fatty liver disease activity score

MICROBIAL NECROMASS WITHIN AGGREGATES STABILIZES PHYSICALLY-PROTECTED C RESPONSE TO CROPLAND MANAGEMENT

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Frontiers of Agricultural Science and Engineering 2023年第2期10卷 198-209页

作者： Ranran zhou Jing TIAN Zhengling cui Fusuo ZHANG College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant-Soil Interactions(Ministry of Education)China Agricultural UniversityBeijing 100193China

The interactions of soil microorganisms and structure regulate the degradation and stabilization processes of soil organic carbon(SOC). Microbial necromass is a persistent component of SOC, and its magnitude of accumulation dependent on management and aggregate sizes. A meta-analysis of 121 paired measurements was conducted to evaluate the management effects on contributions of microbial necromass to SOC depending on aggregate fractions. Results showed that the contribution of fungal necromass to SOC increased with aggregate sizes, while bacterial necromass had a higher proportion in silt and clay. Cropland management increased total and fungal necromass in large macroaggregates(47.1% and 45.6%), small macroaggregates(44.0% and 44.2%), and microaggregates(38.9% and 37.6%).Cropland management increased bacterial necromass independent of aggregate fraction sizes. Greater fungal necromass was increased in macroaggregates in response to manure(26.6% to 28.5%) and no or reduced tillage(68.0% to 73.5%). Cover crops increased bacterial necromass by 25.1%in small macroaggregates. Stimulation of microbial necromass was proportional to the increases of SOC within soil aggregates, and the correlation was higher in macroaggregates. Increasing microbial necromass accumulation in macroaggregates can, therefore, be considered as a central component of management strategies that aim to accelerate C sequestration in agricultural soils.

关键词： cropland management microbial necromass soil aggregates soil carbon sequestration soil organic matter