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A novel X-ray tube spectra reconstruction method based on transmission measurements

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Nuclear Science and Techniques 2016年第2期27卷 73-78页

作者： Jing Cao Chun-Yu Jiang yan-feng zhao Qing-Wei yang Ze-Jie Yin State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China Southwestern Institute of Physics Chengdu 610041 China

A novel X-ray tube spectrum reconstruction method has been proposed based on transmission measurements. Aluminum bars of varying lengths attenuate the X-rays to different levels. The detectors are of lutetium yttrium oxyorthosilicate scintillator and silicon photomultiplier. With the detected X-ray intensities, the X-ray spectrum is unfolded using the least square method. The detectors, aluminum bars, and collimating apertures are integrated in a detection module made of lead. Its response to X-ray is calculated by Monte Carlo codes Geant4. Due to the high photon flux, the detectors work in current *** electronics system, consisting of 24-bit high-precision ADCs with 144 KSPS sampling rate and field programmable gate array, makes the data acquisition process effective and precise. Measurements on a 70-k Vp tungsten anode X-ray were taken to verify the method. The unfolded spectrum agrees well with the simulated spectrum,demonstrating that the method is reliable and practical.

关键词： X射线管重建方法传输测量光谱现场可编程门阵列透射 Geant4 蒙特卡罗程序

Influence of Cu content on the mechanical properties and corrosion resistance of Mg-Zn-Ca bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 487-493页

作者： yan-feng zhao Jian Zhu Li Chang Jing-guo Song Xiao-hua Chen Xi-dong Hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

（***28.8Cas）10o-xCux （at%, x = 0, 1, 3, and 5） bulk metallic glasses （BMGs） of 2 mm in diameter were prepared by the conventional copper mold injection casting method. Besides, the influence of Cu content on the microstructure, thermal stability, mechanical properties, and corrosion behavior of Mg-Zn--Ca BMGs was investigated. It is found that the addition of Cu decreases the glass-forming ability of Mg-Zn-Ca BMGs. Crystalline phases are precipitated at a higher Cu content, larger than 3at%. The compressive fracture strength of Mg-Zn-Ca BMGs is enhanced by the addition of Cu. With the formation of in-situ composites, the compressive strength of the Mg-Zn-Ca alloy with 3at% Cu reaches 979 MPa, which is the highest strength among the Mg-Zn-Ca alloys. Furthermore, the addition of Cu also results in the increase of corrosion potential and the decrease of corrosion current density in Mg-Zn-Ca BMGs, thereby delaying their biodegradability.

关键词： metallic glass glass-forming ability compressive strength corrosion thermal stability

Clinical and microbiological characteristics of patients with biliary disease

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World Journal of Gastroenterology 2020年第14期26卷 1638-1646页

作者： Xue-Xiang Gu Meng-Pei Zhang yan-feng zhao Guang-Ming Huang Department of Gastroenterology The Affiliated Huaian No.1 People's Hospital of Nanjing Medical UniversityHuaian 223001Jiangsu ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210011Jiangsu ProvinceChina Center of Laboratory Medicine The Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210011Jiangsu ProvinceChina

BACKGROUND Biliary diseases are common digestive system disorders which may combine with biliary tract infection such as cholecystitis or ***,rapid identification of the bacteria and their antibiotic susceptibility profiles are crucial for reducing the mortality of patients with biliary tract *** To identify bacterial species and antibiotic susceptibility for antibacterial therapy and analyze bile cultivation risk factors for increasing detection *** This retrospective study was conducted from July 2008 to July *** total,1339 bile samples which were collected during therapeutic endoscopic retrograde cholangiopan-creatography or percutaneous transhepatic cholangiodrainage or other biliary surgeries or biliary drainage were obtained to characterize pathogen spectra,antibiotic susceptibility,and clinical *** data including age,sex,comorbidities,clinical symptoms,protopathies,and history of biliary tract diseases and surgeries were collated from hospital medical *** identification and initial drug susceptibility were further identified by biochemical characterization using the VITEK 2 Compact *** Positive microbiological findings were observed in 738 *** most frequently encountered strains were gram-negative bacteria(74.94%),including Escherichia coli(37.78%),Pseudomonas aeruginosa(8.96%),and Klebsiella pneumoniae(10.29%).Bile bacteria were largely sensitive to carbapenems,piperacillin/tazobactam,and ***-negative strains had low susceptibility to ceftriaxone,quinolones and *** the same microorganisms were present in patients with malignant and benign *** number of samples with Klebsiella pneumoniae in the bile culture were significantly different between patients with malignant and benign diseases(55 vs 30;P=0.019).Age(P<0.001),fever(P<0.001),history of biliary tract diseases and surgeries(both P<0.001),benign disease(P=0.002),and the comorbidity chronic re

关键词： Microorganism Antibiotic susceptibility Bile culture Biliary diseases Retrospective study Detection rate

The Grey Analysis, Kriging and Selection Index of Flower Yield in Rugosa Rose

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Agricultural Sciences in China 2007年第12期6卷 1420-1425页

作者： LI yan-yan feng Zhen zhao Lan-yong MO Zhen-hua ZHANG Bao College of Forestry Shandong Agricultural University Tai＇an 271018 P. R. China

The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant （FY） and 15 other quantitative traits of 20 rugosa rose cultivars. The result showed that： The grey relational grade （GRG） of the number of flowers/plant （NF）, the number of branches/plant （NB）, the width of floral bud （WB）, and the weight/flower （WF） to the FY were larger （〉 0.5）; FY improved with the increase of NF and NB. Moreover, the indirect selection of either trait could not achieve improvement of FY. It is necessary to improve FY by multi-trait selection. The integration selection index （ISI） equation of FY was established with the characters NF, NB, WB, and WF： I= 0.3187x1 - 318.6x2 ＋ 670.1 x4 ＋ 6.3xa, index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide a theoretic basis for the genetic breeding of rugosa rose.

关键词： rugosa rose grey relational grade quantitative traits kriging interpolation index selection

Microstructure analysis of deep rock in Meilinmiao Mine

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 468-473页

作者： Ren-Liang SHAN Li-Wei SONG yan LIU Wen-feng zhao Hui-Xian CHEN School of Mechanics and Civil Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

SEM tests were conducted on four kinds of typical deep rocks in Meilinmiao Mine, and the micro properties were analyzed. The particles of gritstone are unbroken and particle diameter ranges from 80 lam to 400 pro, and the void between particles is wide. The macroscopic failure of gritstone is caused by breakage of the dung distributed between particles, and po- tassium feldspars contained in gritstone are not leached. The failure of medium sandstone is caused by micro cracks distributed in sandstone particles, and potassium feldspars are leached seriously, so the pores penetrate each other and there is close hy- draulic connection in medium sandstone. The particles of fine sandstone are broken, and the particle diameters range from 60 pm to 300 pm, which determines the pores have good connectivity between particles. The dolomites contained in fine sand- stone are corroded, and the micro fracture form belongs to inter-granular fracture. There are no particles and blocks in micro- structure of sandy mudstone, but there are diverse micro cracks. The failure of mudstone arises from the extension of micro cracks, and the microstructure is different from the other three kinds of sandstones obviously.

关键词： SEM test deep rock microstructure leaching crack

Unveiling the evolutionary dynamics of microRNA-targeted plant laccase genes

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Science China(Life Sciences) 2024年第11期67卷 2523-2526页

作者： Rui-Rui He Meng-Qi Lei yan-zhao feng Jiao Xue Yu-Chan Zhang Yue-Qin Chen yang Yu Guangdong Provincial Key Laboratory of Plant Stress Biology State Key Laboratory for BiocontrolSchool of Life ScienceSun Yat-Sen UniversityGuangzhou 510275China Guangdong Key Laboratory of Crop Germplasm Resources Preservation and Utilization Agro-biological Gene Research CenterGuangdong Academy of Agricultural SciencesGuangzhou 510640China

Dear Editor,MicroRNAs(miRNAs)are small noncoding RNA molecules that play crucial roles in the regulation of gene *** have been extensively studied in various organisms,including plants,where they have been found to be involved in diverse biological processes,such as development,growth,and response to environmental *** miRNAs achieve their regulatory functions by binding to the mRNA of target genes and modulating their expression *** recent years,there has been growing interest in understanding the evolutionary aspects of miRNA-target interactions in plants(Cui et al.,2017).The evolution of miRNAs and their target genes can provide valuable insights into the mechanisms underlying the development and adaptation of plant *** intriguing aspect of miRNA evolution is their co-evolution with specific target genes,which can have significant implications for plant phenotypic variation and evolution.

关键词： expression evolutionary

Relationship between DNA ploidy, expression of ki-67 antigen and gastric cancer metastasis

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World Journal of Gastroenterology 1999年第1期5卷 15-16页

作者： XU Lei, ZHANG Su Min, WANG yan Ping, zhao feng Kai, WU Dong Ying and XIN yan

AIM To evaluate the relationship between the expression of Ki 67 antigen and the pathobiological behaviours of gastric cancers especially their distant metastases. METHODS Fifty six specimens of gastric cancer routinely fixed in formalin and embedded in paraffin (FFEP) were studied by immunohistochemical method. RESULTS Expression of Ki 67 antigen was significantly related to the distant metastases to liver, ovary and adrenal gland ( P 0 05). Furthermore, the Ki 67 antigen expression was significantly related to the DNA aneuploidy pattern, which is closely related to poor prognosis ( P <0 05). CONCLUSION Overexpression of Ki 67 can be used as an objective marker of the proliferative activity for predicting prognosis of gastric cancer and metastatic potential to distant organs.

关键词： Ki 67 antigen neoplasms metastasis immunochemistry DNA ploidy stomach neoplasms/pathology

Disruption of estrogen receptor beta in mice brain results in pathological alterations resembling Alzheimer disease

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Acta Pharmacologica Sinica 2004年第4期25卷 54-59页

作者： Qing-hong ZHANG2, yan-hong HUANG3, Yu-zhen HU, Geng-ze WEI,Xue-feng HAN, Shun-yan LU, Yu-feng zhao 2Department of Physiology, Institute of Basic Medical Science, Departmentof Gynaecology and obstetrics, 3 Xijing Hospital, The Fourth Military MedicalUniversity, Xi-an 710032, Shaanxi, China Department of Physiology Institute of Basic Medical Science Department of Gynaecology and obstetrics Xijing Hospital The Fourth Military Medical University

AIM: To study the pathological characteristics of the mice with estrogen receptor β (ERβ) disruption in brain. METHODS: Immunohistochemistry method was applied in the study. RESULTS: β-Amyloid peptide(Aβ42) and apolipoprotein E (ApoE) immunoreactive substances were accumulated notably in cortex and limbic structures such as the hippocampus and amygdala in brain, resembling the pathological changes of human Alzheimer disease (AD). Aβ formed cloudy-like deposits in parenchyma of brain, while apoE also deposited along or surrounding the blood vessels. CONCLUSIONS: ERβ is crucial to the development of neural degenerative disease, so modulation of Aβ metabolism via ERβ signal pathway might be beneficial for AD prevention or therapy.

关键词： beta-amyloid peptide apolipoprotein E estrogen receptor beta Alzheimer disease

Over-expressed Genes Detected by Suppression Subtractive Hybridization in Carcinoma Derived From Transformed 16HBE Cells Induced by BPDE

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Biomedical and Environmental Sciences 2005年第5期18卷 302-306页

作者： SHE-JUAN AN JIA-KUN CHEN LI-LI LIU yan-feng zhao XUE-MIN CHEN Department of Occupational and Environmental Health School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Department of Occupational and Environmental Health School of Public Health Institute for Chemical Carcinogenesis Guangzhou Medical College Guangzhou 510182 Guangdong China

To screen the over differentially expressed genes in carcinoma induced by BPDE-transformed 16HBE cells （16HBE-C cells）. Methods The suppression subtractive hybridization （SSH） method was performed to profile differentially expressed genes between 16HBE-C cells and 16HBE cells. The cDNA fragments of differentially expressed genes were inserted into TA cloning vector and transformed competent E. coli strain. Positive clones were randomly picked up and identified by the colony PCR method. Dot blot was used to test the same source with the tester. The differentially expressed cDNA fragments were sequenced and compared with known genes and EST database in Genbank. Results Eight known genes were over-expressed in 16HBE-C cells including eukaryotic translation elongation factor 1 alpha 1, HIF-1 responsive RTP801, ribosomal protein L10 （RPL10）, ribosomal protein S29 （RPS29）, mitochondrion related genes, and laminin receptor 1. Three differentially expressed cDNA fragments could not be matched to the known genes but to the EST database. Conclusion The SSH method can detect differentially expressed genes between 16HBE-C and 16HBE cells. BPDE-induced carcinogenesis may be related to alteration of at least eight known genes and three unknown genes. These expression data provide a clue to further cloning novel genes and studying functions in BPDE-induced carcinoma.

关键词： Anti-BPDE Hybridization Gene