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China Foundry 2022年第2期19卷 99-108页

作者： Yong-zhi Hao Hai-dong Zhao Xu Shen Xue-ling wang Hui-ting Zheng National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Al-Si-Mg alloys are the most commonly used material in high vacuum die-casting(HVDC),in which the morphology and distribution ofα-Al grains have important effect on mechanical properties.A multi-component quantitative cellular automaton(CA)model was developed to simulate the microstructure and microsegregation of HVDC Al-Si-Mg alloys with different Si contents(7%and 10%)and cooling rates during *** grain number and average grain size with electron backscatter diffraction(EBSD)analysis were used to verify the *** relationship between grain size and nucleation order as well as nuclei density was investigated and *** is found that the growth of grains will be restrained in the location with higher nuclei *** influence of composition and cooling rate on the solute transport reveals that for AlSi7Mg0.3 alloy the concentration of solute Mg in liquid is higher at the beginning of eutectic *** comparison between simulation and experiment results shows that externally solidified crystals(ESCs)have a significant effect for samples with high cooling rate and narrow solidification interval.

关键词： Al-Si-Mg alloys high vacuum die-casting cellular automaton α-Al grains external solidification crystals

Spatial Structure of Peer Networks and Academic Achievement Based on a Random Control Trial Experiment

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China & World Economy 2024年第3期32卷 67-97页

作者： Shilan Feng Ya Tan zhi wang Qinghua Zhang School of Marxism Peking UniversityChina School of International Trade and Economics University of International Business and EconomicsChina China Center for Economic Studies Fudan Universityand Shanghai Institute of International Finance and EconomicsChina Guanghua School of Management Peking UniversityChina

This paper investigates whether changing the seating arrangement in a classroom can facilitate positive spillovers from top-performing students to others,using a field experiment conducted in a Chinese high *** study groups with balanced abilities,the treatment altered the spatial distribution by assigning the two top students to seats in the spatial center of each *** the reference groups where students were allowed to choose their own seating arrangements,the lowest performing were significantly less likely to sit next to a top student than they would be under a random *** results suggest that,in the treated groups,there could be enhanced academic spillovers from the top *** treatment especially benefited the two lowest performing students in science *** contrast,the treatment exerted negative effects on the test scores of the two middle-performing students,due to a disruption *** results suggest that the spatial layout of a peer network can have a significant impact on learning outcomes.

关键词： field experiment peer effects social interactions spatial structure test scores

Promoter methylation of tumor suppressor genes in esophageal squamous cell carcinoma

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Chinese Journal of Cancer 2013年第1期32卷 3-11页

作者： Ji-Sheng Li Jian-Ming ying Xiu-Wen wang Zhao-Hui wang Qian Tao Li-Li Li Department of Chemotherapy Cancer CenterQilu HospitalShandong University Department of Pathology Cancer Hospital & InstitutePeking Union Medical College and Chinese Academy of Medical Sciences Cancer Epigenetics Laboratory Department of Clinical OncologySir YK Pao Center for Cancer and Li Ka Shing Institute of Health SciencesThe Chinese University of Hong Kong Hong Kong and CUHK Shenzhen Research Institute Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences(CAS)-CUHK

Esophageal squamous cell carcinoma(ESCC) is a prevalent and fatal cancer in China and other Asian *** silencing of key tumor suppressor genes(TSGs) is critical to ESCC initiation and ***,many novel TSGs silenced by promoter methylation have been identified in ESCC,and these genes further serve as potential tumor markers for high-risk group stratification,early detection,and prognosis *** review summarizes recent discoveries on aberrant promoter methylation of TSGs in ESCC,providing better understanding of the role of disrupted epigenetic regulation in tumorigenesis and insight into diagnostic and prognostic biomarkers for this malignancy.

关键词：基因启动子抑癌基因鳞状细胞癌食管癌甲基化肿瘤抑制基因肿瘤标志物表观遗传

dep1 improves rice grain yield and nitrogen use efficiency simultaneously by enhancing nitrogen and dry matter translocation

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Journal of Integrative Agriculture 2022年第11期21卷 3185-3198页

作者： HUANG Li-ying Li Xiao-xiao ZHANG Yun-bo Shah FAHAD wang Fei National Key Laboratory of Crop Genetic Improvement MARA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze RiverCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070P.R.China Engineering Research Center of Ecology and Agricultural Use of Wetland Ministry of EducationYangtze UniversityJingzhou 434025P.R.China College of Agriculture Yangtze UniversityJingzhou 434025P.R.China Hubei Collaborative Innovation Center for Grain Industry Yangtze UniversityJingzhou 434025P.R.China Department of Agronomy The University of HaripurHaripur 22620Pakistan

The rice cultivars carrying dep1(dense and erect panicle 1)have the potential to achieve both high grain yield and high nitrogen use efficiency(NUE).However,few studies have focused on the agronomic and physiological performance of those cultivars associated with high yield and high NUE under field ***,we evaluated the yield performance and NUE of two near-isogenic lines(NILs)carrying DEP1(NIL-DEP1)and dep1-1(NIL-dep1)genes under the Nanjing 6 background at 0 and 120 kg N ha^(–1).Grain yield and NUE for grain production(NUEg)were 25.5 and 21.9%higher in NIL-dep1 compared to NIL-DEP1 averaged across N treatments and planting years,*** yield advantage of NIL-dep1 over NIL-DEP1 was mainly due to larger sink size(i.e.,higher total spikelet number),grainfilling percentage,total dry matter production,and harvest index.N utilization rather than N uptake contributed to the high yield of *** higher NUEg in NIL-dep1 was associated with higher N and dry matter translocation efficiency,lower leaf and stem N concentration at maturity,and higher glutamine synthetase(GS)activity in *** conclusion,dep1 improved grain yield and NUE by increasing N and dry matter transport due to higher leaf GS activity under field conditions during the grain-filling period.

关键词： dep1 grain yield nitrogen use efficiency nitrogen translocation rice

Genetic transformation ofpopulusxeuramericana cv. guariento with chitinase gene

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Journal of Agricultural Science and Technology 2009年第12期3卷 25-29页

作者： ZHANG Fu-li XIONG Zhong-ping wang zhi-ying Northeast Forestry University Harbin 150040 China Southwest Forestry College Kunming 650224 China Zhoukou Normal University Zhoukou Henan 466000 China

In this paper, populus xeuramericana cv. Guariento was transformed with bean chitinase by Agrobacterium tumefaciens-mediated leaf disc method. Firstly, the leaf explants were pre-cultured at 25℃ for 2d. Secondly, they were infected in Agrobacterium tumefaciens suspension （OD600=0.5） for 20 rain, then were co-cultured for 3d in the dark. Thirdly, the explants were transferred to the selection culture medium （containing Kanamycin 40 mg.L^-1 and Cefotaxime Sodium 800 mg-L1） and incubated at 25℃ until resistance buds formed. Chitinase activity was determined for the positive plants by PCR and PCR-Southern blot hybridization analysis. And, chitinase activity of positive plants was significantly higher than that of control plant, and the highest ratio of activity of NO.4 to that of control was 3.41. It showed that bean chitinase gene had been expressed in the plant genome.

关键词： chitinase gene populusxeuramericana cv.guariento transformation

Treatment of dilated cardiomyopathy caused by coronary microvascular dysfunction with anisodamine: a report of 5 cases

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Journal of Traditional Chinese Medicine 2020年第2期40卷 340-342页

作者： Xu zhiwei wang Tong Chen Liang Lou ying Sun Xiaoyan Jiang Jinqi Department of Cardiac Surgery Huai'an First People's HospitalThe Affiliated Huaian No.1 People's Hospital of Nanjing Medical UniversityHuai'an223000China Department of Emergency Shanghai Chest HospitalShanghai Jiaotong UniversityShanghai 200030China Department of Nuclear Medicine Shanghai Chest HospitalShanghai Jiaotong UniversityShanghai 200030China

The management of dilated cardiomyopathy(DCM) is well established. However, a subset of patients does not have recovery from or have recurrences of left ventricular(LV) dysfunction despite receiving optimal medical therapy. Coronary microvascular dysfunction(CMD) can result from structural and functional abnormalities at the intramural and small coronary vessel level affecting coronary blood flow autoregulation and consequently leading to impaired coronary flow reserve. Dilated myocardial phenotype may be responsible for CMD in DCM. Anisodamine can exert a significant effect on relieving microvascular spasm, and improving and dredging the coronary microcirculation. However,whether CMD can be potentially improved with anisodamine to make DCM better remains incompletely understood.

关键词： Anisodamine Coronary microvascular dysfunction Cardiomyopathy,dilated Case reports

The Effect of Intensity Pulsed Ion Beam Irradiation on Wear Resistance of High-speed Steel

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材料热处理学报 2004年第05B期25卷 1049-1052页

作者： MEIXian-xiu HAOSheng-zhi MATeng-cai wangying-min LIUZhen-min StateKeyLaboratoryforMaterialsModificationbyLaser IonandElectronBeamsDepartmentofPhysicsDalianUniversityofTechnologyDalian116024China

The structural and phase transformations occurring in the near-surface layers of pre-quenched W6Mo5Cr4V2 high-speed steel (HSS) subjected to intensity pulsed ion beam (IPIB) melting have been investigated. The effect of IPIB irradiation on wear resistance of the HSS has also been studied. The IPIB consists mainly of Cn+(30%)^0 H+(70%), with a high beam current density of 80A/cm2, acceleration voltage of 250kV, pulse duration of 70 ns. Samples were bombarded with 1, 3, 5 pulses respectively. It has been revealed that after IPIB irradiation the initial martensite in the near-surface layer of HSS changed into austenite and produced residual stresses by using electron microscopy and X-ray diffraction. Redistribution and interlace of dislocations in the irradiated samples were generated under the impact of shock wave. With increasing pulse times gradual liquid-phase dissolution of M6C carbide particles occurs in the near-surface layer and produces nanocrystalline MC. This process results in the decrease of martensite crystal (a-phase) and increase of austenite (y-phase) content and the dispersed carbide. Wear resistance of the HSS is improved by a factor of 2, which is explained by the formation of metastable phases such nanocrystal and residual stresses and the redistribution and interlace of dislocations.

关键词：高速钢磨损性能强脉冲离子束热处理

Innate immune targets of hepatitis B virus infection

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World Journal of Hepatology 2016年第17期8卷 716-725页

作者： zhi-Qiang Zou Li wang Kai wang Ji-Guang Yu Infectious Disease Hospital of Yantai Hepatology Department Qilu Hospital of Shandong University

Approximately 400 million people are chronically infected with hepatitis B virus(HBV) globally despitethe widespread immunization of HBV vaccine and the development of antiviral therapies. The immunopathogenesis of HBV infection is initiated and driven by complexed interactions between the host immune system and the virus. Host immune responses to viral particles and proteins are regarded as the main determinants of viral clearance or persistent infection and hepatocyte injury. Innate immune system is the first defending line of host preventing from virus invasion. It is acknowledged that HBV has developed active tactics to escape innate immune recognition or actively interfere with innate immune signaling pathways and induce immunosuppression, which favor their replication. HBV reduces the expression of pattern-recognition receptors in the innate immune cells in humans. Also, HBV may interrupt different parts of antiviral signaling pathways, leading to the reduced production of antiviral cytokines such as interferons that contribute to HBV immunopathogenesis. A full comprehension of the mechanisms as to how HBV inactivates various elements of the innate immune response to initiate and maintain a persistent infection can be helpful in designing new immunotherapeutic methods for preventing and eradicating the virus. In this review, we aimed to summarize different branches the innate immune targeted by HBV infection. The review paper provides evidence that multiple components of immune responses should be activated in combination with antiviral therapy to disrupt the tolerance to HBV for eliminating HBV infection.

关键词： Hepatitis B virus Infection Targets Innate immune response Signaling pathway

Ku80 gene G-1401T promoter polymorphism and risk of gastric cancer

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World Journal of Gastroenterology 2011年第16期17卷 2131-2136页

作者： Jia-Qi Li Jie Chen Nan-Nan Liu Li Yang ying Zeng Bin wang Xue-Rong wang Key Laboratory of Reproductive Medicine Department of Pharmacology Nanjing Medical University Nan-jing 210029 Jiangsu Province China Department of General Surgery First Affiliated Hospitalof Nanjing Medical University. Nanjing 210029 Jiangsu Province China

AIM:To evaluate the possible relationship between the Ku80 gene polymorphism and the risk of gastric cancer in ***:In this hospital-based case-control study of gastric cancer in Jiangsu Province,China,we investigated the association of the Ku80 G-1401T (rs828907) polymorphism with gastric cancer risk.A total of 241 patients with gastric cancer and 273 age-and sexmatched control subjects were genotyped and analyzed by polymerase chain reaction-restriction fragment length ***:The frequencies of genotypes GG,GT and TT were 65.6%,22.8% and 11.6% in gastric cancer cases,respectively,and 75.8%,17.6% and 6.6% in controls,*** were significant differences between gastric cancer and control groups in the distribution of their genotypes (P=0.03) and allelic frequencies (P=0.002) in the Ku80 promoter G-1401T ***:The T allele of Ku80 G-1401T may be associated with the development of gastric cancer.

关键词： Ku80 Gastric cancer Polymorphism Promoter Carcinogenesis

Secoemestrin C Ameliorates Psoriasis-like Skin Inflammation in Mice by Suppressing the TNF-α/NF-κB Signaling Pathway

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Current Medical Science 2024年第1期44卷 232-240页

作者： zhi-bin ZHU Meng-jie LIU Jing wang Zhou SHU Jie CAO Department of Stomatology Chengdu Seventh People's HospitalChengdu 610044China Department of Pharmacy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective Secoemestrin C(SC),an epitetrathiodioxopiperazine isolated from Aspergillus nidulans,has been previously reported to have immunomodulatory and hepatoprotective effects against acute autoimmune ***,the effect of SC on regulating the inflammation and its underlying mechanisms in the pathogenesis of psoriasis remain *** study aimed to evaluate the effects of SC on inflammatory dermatosis both in vitro and in *** In vitro,HaCaT cells were induced with tumor necrosis factor-alpha(TNF-α,10 ng/mL)to establish an inflammatory injury model,and the expression of nuclear transcription factor-κB(NF-κB)pathway components was measured using qRT-PCR and Western *** in vivo mouse model of imiquimod(IMQ)-induced psoriasis-like skin inflammation was used to evaluate the effectiveness of SC in alleviating *** SC significantly blocked the activation of NF-κB signaling in TNF-α-stimulated HaCaT *** addition,systemic and local administration of SC improved psoriatic dermatitis in the IMQ-induced mouse *** reduced skin scale and significantly inhibited the secretion of inflammatory factors in skin *** The protective effect of SC against psoriatic-associated inflammation reveals its potential therapeutic value for treating psoriasis.

关键词： secoemestrin C(SC) psoriasis tumor necrosis factor-alpha(TNF-α) nuclear transcription factor-kB(NF-kB) inflammation