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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： zhao-qing zhang Kai-Ning Shi Yao-Yao Shi Yi-Hui Song Zhe He Ya-Song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

The Expression of the IGF Family During Mouse Mammary Gland Development

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Agricultural Sciences in China 2007年第9期6卷 1149-1156页

作者： zhao Feng LI qing-zhang The Key Laboratory of Dairy Science Ministry of Education~Northeast Agricultural University Harbin 150030 P.R.China

This study was to determine the patterns and levels of IGF family members＇ expression during postnatal mammary gland development. The authors investigated the protein expression profile of the major components of the IGF axis in murine mammary glands. All the proteins examined, IGF- Ⅰ, IGF- Ⅱ, and IGF- Ⅰ receptor （IGF-Ⅰ R） were expressed at greatly different levels and displayed unique expression profiles. IGF- Ⅱ and IGF- ⅠR were always expressed at significantly higher levels than IGF- Ⅰ. IGF- Ⅰwas localized in adipocytes as well as the epithelial and stromal compartments, but just distinctly expressed where mammary cells aggregated to form ducts, in virgins. The IGF- Ⅱ was localized only on the basal layer epithelial cell membranes of ducts and alveoli, with a peak level on the initiation of lactation. The higher level of IGF- ⅠR compared with IGF- Ⅰ was also found in adipocytes as well as in the epithelial and stromal compartments, especially during pregnancy and late lactation. The IGF- Ⅰ R pathway was obviously significant for the development of the mammary parenchyma and stroma. Overall, the comparison of the expression profiles of these different proteins would strongly suggest that they were likely to have different functions throughout the mammary gland development, and it also highlighted the potential interactions and coregulation of the members of this axis. It seems that IGF- Ⅱ was the major local modulator rather than IGF- Ⅰ by an IGF- Ⅰ R-independent pathway, especially for initiation of lactation. This study has demonstrated the importance and complexity of the IGF axis during mammary gland development and provides a valuable resource for future research in this area.

关键词： mammary gland insulin-like growth factors receptor laser scanning confocal microscope (LSCM)

Variable Selection of Generalized Regression Models Based on Maximum Rank Correlation

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 833-844页

作者： Peng-jie DAI qing-zhao zhang Zhi-hua SUN School of Business Renmin University of China Department of Mathematics University of Chinese Academy of Sciences

In this paper, we investigate the variable selection problem of the generalized regression models. To estimate the regression parameter, a procedure combining the rank correlation method and the adaptive lasso technique is developed, which is proved to have oracle properties. A modified IMO （iterative marginal optimization） algorithm which directly aims to maximize the penalized rank correlation function is proposed. The effects of the estimating procedure are illustrated by simulation studies.

关键词： maximum rank correlation estimation adaptive LASSO oracle properties generalized regression models.

Sub-Homogeneous Peridynamic Model for Fracture and Failure Analysis of Roadway Surrounding Rock

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3167-3187页

作者： Shijun zhao qing zhang Yusong Miao Weizhao zhang Xinbo zhao Wei Xu School of Science Qingdao University of TechnologyQingdao266520China College of Mechanics and Materials Hohai UniversityNanjing211100China Xibei Mining Co. Ltd.Shandong Energy GroupXi’an710018China

The surrounding rock of roadways exhibits intricate characteristics of discontinuity and *** address these complexities,this study employs non-local Peridynamics(PD)theory and reconstructs the kernel function to represent accurately the spatial decline of long-range ***,modifications to the traditional bondbased PD model are *** considering the micro-structure of coal-rock materials within a uniform discrete model,heterogeneity characterized by bond random pre-breaking is *** approach facilitates the proposal of a novel model capable of handling the random distribution characteristics of material heterogeneity,rendering the PD model suitable for analyzing the deformation and failure of heterogeneous layered coal-rock mass *** established numerical model and simulation method,termed the sub-homogeneous PD model,not only incorporates the support effect but also captures accurately the random heterogeneous micro-structure of roadway surrounding *** simulation results obtained using this model show good agreement with field measurements from the Fucun coal mine,effectively validating the model’s capability in accurately reproducing the deformation and failure mode of surrounding rock under bolt-supported(anchor cable).The proposed subhomogeneous PD model presents a valuable and effective simulation tool for studying the deformation and failure of roadway surrounding rock in coal mines,offering new insights and potential advancements.

关键词： Roadway surrounding rock peridynamics heterogeneous material fracture analysis numerical simulation

Protein neddylation and its role in health and diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1869-1904页

作者： Shizhen zhang qing Yu Zhijian Li Yongchao zhao Yi Sun Department of Breast Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Institute of Translational Medicine Zhejiang University School of MedicineHangzhou 310029China Department of Thyroid Surgery Zhejiang Cancer HospitalInstitute of Basic Medicine and Cancer(IBMC)Chinese Academy of SciencesHangzhou 310022China Key Laboratory of Head&Neck Cancer Translational Research of Zhejiang Province Hangzhou 310022China Department of Hepatobiliary and Pancreatic Surgery Zhejiang University School of MedicineHangzhou 310029China Zhejiang Provincial Key Laboratory of Pancreatic Disease The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Zhejiang University Cancer Center Hangzhou 310029China Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Hangzhou 310024China Research Center for Life Science and Human Health Binjiang Institute of Zhejiang UniversityHangzhou 310053China

NEDD8(Neural precursor cell expressed developmentally downregulated protein 8)is an ubiquitin-like protein that is covalently attached to a lysine residue of a protein substrate through a process known as neddylation,catalyzed by the enzyme cascade,namely NEDD8 activating enzyme(E1),NEDD8 conjugating enzyme(E2),and NEDD8 ligase(E3).The substrates of neddylation are categorized into cullins and non-cullin *** of cullins activates CRLs(cullin RING ligases),the largest family of E3 ligases,whereas neddylation of non-cullin substrates alters their stability and activity,as well as subcellular ***,the neddylation pathway and/or many neddylation substrates are abnormally activated or over-expressed in various human diseases,such as metabolic disorders,liver dysfunction,neurodegenerative disorders,and cancers,among ***,targeting neddylation becomes an attractive strategy for the treatment of these *** this review,we first provide a general introduction on the neddylation cascade,its biochemical process and regulation,and the crystal structures of neddylation enzymes in complex with cullin substrates;then discuss how neddylation governs various key biological processes via the modification of cullins and non-cullin *** further review the literature data on dysregulated neddylation in several human diseases,particularly cancer,followed by an outline of current efforts in the discovery of small molecule inhibitors of neddylation as a promising therapeutic ***,few perspectives were proposed for extensive future investigations.

关键词： NEDD8 attached attractive

Identification and validation of novel prognostic fatty acid metabolic gene signatures in colon adenocarcinoma through systematic approaches

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Oncology Research 2024年第2期32卷 297-308页

作者： HENG zhang WENJING CHENG HAIBO zhao WEIDONG CHEN QIUJIE zhang qing-qing YU Department of Laboratory Shandong Daizhuang HospitalJining272051China Jining No.1 People’s Hospital Shandong First Medical UniversityJining272000China

Colorectal cancer(CRC)belongs to the class of significantly malignant tumors found in ***,dysregulated fatty acid metabolism(FAM)has been a topic of attention due to its modulation in cancer,specifically ***,the regulatory FAM pathways in CRC require comprehensive ***:The clinical and gene expression data of 175 fatty acid metabolic genes(FAMGs)linked with colon adenocarcinoma(COAD)and normal cornerstone genes were gathered through The Cancer Genome Atlas(TCGA)-COAD corroborating with the Molecular Signature Database v7.2(MSigDB).Initially,crucial prognostic genes were selected by uni-and multi-variate Cox proportional regression analyses;then,depending upon these identified signature genes and clinical variables,a nomogram was ***,to assess tumor immune characteristics,concomitant evaluation of tumor immune evasion/risk scoring were ***:A 8-gene signature,including ACBD4,ACOX1,CD36,CPT2,ELOVL3,ELOVL6,ENO3,and SUCLG2,was generated,and depending upon this,CRC patients were categorized within high-risk(H-R)and low-risk(L-R)***,risk and age-based nomograms indicated moderate discrimination and good *** data confirmed that the 8-gene model efficiently predicted CRC patients’***,according to the conjoint analysis of tumor immune evasion and the risk scorings,the H-R cohort had an immunosuppressive tumor microenvironment,which caused a substandard ***:This investigation established a FAMGs-based prognostic model with substantially high predictive value,providing the possibility for improved individualized treatment for CRC individuals.

关键词： Fatty acid metabolism Colorectal cancer Gene signatures Machine learning

Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang zhang qing-Lin Cheng Wei Sun Yi zhao Zhi-Min Li Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

Targeted multi-agent communication algorithm based on state control

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Defence Technology（防务技术） 2024年第1期31卷 544-556页

作者： Li-yang zhao Tian-qing Chang Lei zhang Jie zhang Kai-xuan Chu De-peng Kong Department of Weaponry and Control Army Academy of Armored ForcesBeijing100072China Unit 92942 Beijing100161China

As an important mechanism in multi-agent interaction,communication can make agents form complex team relationships rather than constitute a simple set of multiple independent ***,the existing communication schemes can bring much timing redundancy and irrelevant messages,which seriously affects their practical *** solve this problem,this paper proposes a targeted multiagent communication algorithm based on state control(SCTC).The SCTC uses a gating mechanism based on state control to reduce the timing redundancy of communication between agents and determines the interaction relationship between agents and the importance weight of a communication message through a series connection of hard-and self-attention mechanisms,realizing targeted communication message *** addition,by minimizing the difference between the fusion message generated from a real communication message of each agent and a fusion message generated from the buffered message,the correctness of the final action choice of the agent is *** evaluation using a challenging set of Star Craft II benchmarks indicates that the SCTC can significantly improve the learning performance and reduce the communication overhead between agents,thus ensuring better cooperation between agents.

关键词： Multi-agent deep reinforcement learning State control Targeted interaction Communication mechanism

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

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Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： Si-Na Wei zhao-qing Feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(***). Using the ***, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the *** are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich ***, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field

Improvement for creep strength of a second-generation single crystal superalloy by design of heat treatments

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Rare Metals 2024年第1期43卷 342-350页

作者： Wan-Shun Xia Xin-Bao zhao Jia-Chen Xu Quan-zhao Yue qing-qing Ding Huan-Chang Duan Yue-Feng Gu Hong-Bin Bei Ze zhang Institute of Superalloys Science and Technology School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Silicon and Advanced Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Design of heat treatments is related to the key technology for development of nickel-based single crystal superalloys(Ni-SXs). Based on the full understanding of the solidification characteristics, this work applies optimization design of heat treatments for a second-generation Ni-SX. Microstructure evolution and creep properties are compared in the material under conventional/standard(Std.) and optimized(Opt.) treatments. For the Std. sample,strong dendritic segregations determine inconsistent microstructure evolution in the dendritic(D) and interdendritic region(ID), while the latter serves as weak area to have the prior microcrack initiation, damaging overall performance of the alloy. The Opt. treatment applies higher homogenization temperature, leading to overall reduced segregations, while not inducing incipient melting. A lower temperature of first-step ageing is used to lower the size ofγ'particles. These help to form the more uniform microstructure in dendritic and interdendritic region and relieve the inconsistent microstructure evolution. The balanced local strength makes ID no longer as the weak area,thus restricting microcrack initiation. Great improvement of high temperature and low stress property is obtained by this progress, leading to the pronounced increase of creep rupture life under 1100 °C/140 MPa.

关键词： Single crystal superalloy Heat treatment Segregation Solidification Creep property