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Mechanical characteristics and microcosmic mechanisms of granite under temperature loads

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Journal of China University of Mining and Technology 2008年第3期18卷 413-417页

作者： xu xiao-li GAO Feng SHEN xiao-ming XIE He-ping School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China School of Architecture and Civil Engineering Nantong University Nantong Jiangsu 226019 China Sichuan University Chengdu Sichuan 610065 China

The relationships between mechanical characteristics of rock and microcosmic mechanism at high temperatures were investigated by MTS815, as well as the stress-strain behavior of granite under the action of temperatures ranging from room temperature to 1200 ℃. Based on a micropore structure analyzer and SEM, the changes in rock porosity and micro structural morphology of sample fractures and brittle-plastic characteristics under high temperatures were analyzed. The results are as follows： 1） Mechanical characteristics do not show obvious variations before 800 ℃; strength decreases suddenly after 800 ℃ and bearing capacity is almost lost at 1200 ℃. 2） Rock porosity increases with rising temperatures; the threshold temperature is about 800 ℃; at this temperature its effect is basically uniform with strength decreasing rapidly. 3） The failure type of granite is a brittle tensile fracture at temperatures below 800 ℃ which transforms into plasticity at temperatures higher than 800 ℃ and crystal formation takes place at this time. Chemical reactions take place at 1200 ℃. Failure of granite under high temperature is a common result of thermal stress as indicated by an increase in the thermal expansion coefficient, transformation to crystal formation of minerals and structural chemical reactions.

关键词： granite mechanical characteristics temperature effect microcosmic mechanism

KAI1 is a potential target for anti-metastasis in pancreatic cancer cells

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World Journal of Gastroenterology 2008年第7期14卷 1126-1132页

作者： Jian-Hua xu xiao-Zhong Guo li-Nan Ren li-Chun Shao Min-Pei liu Department of Gastroenterology The General Hospital of Shenyang Military Command Shenyang 110016 Liaoning Province China

AIM: To investigate whether KAI1, as a metastasis suppressor gene, is associated with invasive and metastatic ability of pancreatic cancer ***: KAI1 gene was transfected into pancreatic cancer cell line MiaPaCa Ⅱ by liposomes selected with G418. Expression of transfected cells was measured by Western blotting, immunofluorescence and immunocytochemistry. Tumor cell invasion and metastatic ability were detected through gelatinase activity and reconstituted basement membrane (Matrigel) assay. pCMV-KAI1 was directly injected into the heterotopic human pancreatic adenocarcinoma successfully established in the groin of BALB/C nude mice, by subcutaneous injection of MiaPaCa Ⅱ pancreatic cancer cells. The statistical analysis between groups was determined by Student's two tailed t ***: By Western blotting, MiaPaCa Ⅱ cells transfected by KAI1 gene indicated KAI1 expression at approximately 29.1 kDa. Cytoplasm staining was positive and uniformly spread in transfected cancer cells, using immunohistochemistry and immunofluorescence. The most obvious difference was present after 30 h (MiaPaca Ⅱ 43.6 ± 9.42, pCMV-MiaPaca Ⅱ 44.8 ± 8.56, pCMV-KAI1-MiaPaca Ⅱ 22.0 ± 4.69, P lipofectamine 1.22 ± 0.31 in A group were lower than control 4.61 ± 1.98 and pCMV-KAI 11.67 ± 0.81. Analyses of metastases with and without KAI1 transfection in mice were different in liver and lung between controls 1.62 ± 0.39, 0.45 ± 0.09, pCMV-KAI 1.01 ± 0.27, 0.33 ± 0.09 and KAI1-lipofectamine 0.99 ± 0.21, 0.30 ± 0.09 respectively (P lity. KAI1 gene plays an important role in inhibiting metastasis of

关键词： KAI1 Pancreatic cancer cell line Transfection Immunocytochemistry Western blotting Immunofluorescence Gelatinolysis

Fabrication of poly(2,6-pyridinedicarboxylic acid)/MWNTs modified electrode for simultaneous determination of guanine and adenine in DNA

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Chinese Chemical Letters 2011年第8期22卷 981-984页

作者： Ke Qin Deng Chun Xiang li Yu lin ling Guo Rong xu xiao Fang li Chemistry and Chemical Engineering College Hunan University of Science and Technology Xiangtan 411201 China

The fabrication of poly（2,6-pyridinedicarboxylic acid）/MWNTs modified glass electrode（PPDA/MWNTs/GCE） was proposed and used for individual or simultaneous determination of guanine and *** performances of the PPDA/MWNTs/GCE were characterized with cyclic voltammetry（CV）.The modified electrode exhibited enhanced electrocatalytic behavior and good stability for the detection of guanine and *** pulse voltammetry（DPV） was used to determine the concentration of guanine,*** detection limit（S/N = 3） for guanine and adenine was 0.045μmol/L and 0.05μmol/L,*** electrochemical method for the measurement of guanine and adenine in calf thymus DNA was also developed with this modified electrode and the result was satisfactory.

关键词： Multi-wall carbon nanotubes 2 6-Pyridinedicarboxylic acid Guanine Adenine Calf thymus dsDNA

Relation Between Endodormancy Induction and Changes in Two Main Electron Transport Pathways of Nectarine Buds

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Agricultural Sciences in China 2008年第10期7卷 1203-1209页

作者： YU Qin GAO Dong-sheng xu xiao-ming li Jin xu Chen-shan State Key Laboratory of Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an271018. P.R.China

Operation regulations of two main electron transport pathways in nectarine （Prunus persica var. nectariana cv. Shuguang） buds during endodormancy induction were studied to understand possible roles which two main electron transport pathways played in the buds of deciduous fruit trees during endodormancy induction. Respiratory inhibitors （KCN and SHAM） were used to investigate total respiration rate （Vt）, the development and operation of the alternative pathway and partitioning of electrons between the cytochrome and alternative pathways in nectarine buds during endodormancy induction. Results indicated that changes of Vt in flower and leaf buds showed single and double hump-shaped curves, respectively. In endodormancy induction, the capacity （Valt,） and activity （ρValt） of the alternative pathway rapidly increased, but changes of them had different patterns during the entire measuration. At the same time, changes of engagements of the alternative （ρValt/Vt） and cytochrome pathway （ρ′Vcyt/Vt） were opposite, and ρ′Vcyt/Vt was always further higher than ρValt/Vt during the entire measuration. All these results indicated that the development and operation of the alternative pathway played important roles in endodormancy induction, but the cytochrome pathway was the main pathway for mitochondrial electron transport in buds during endodormancy induction.

关键词： nectarine buds endodormancy induction cytochrome pathway alternative pathway

Analysis on characteristics of 1-D apodized and chirped photonic crystals containing negative refractive materials

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Optoelectronics Letters 2008年第6期4卷 440-442页

作者： TONG Kai CUI Wei-wei xu xiao-hui li Zhi-quan College of Electric Engineering University of Yanshan Qinhuangdao 066004China

Using transfer matrix method,the optical transmission properties of 1-D photonic crystals composed partially of negative refraction media are analyzed. The transmission spectra of periodic photonic crystal,chirped photonic crystal and apodized photonic crystal are numerically simulated respectively. By contrast with optical transmission properties of ordinary photo-nic crystals made of positive refraction media,the transmission spectra of apodized photonic crystal become unregular,the Bragg flat-headed area recurs but the peak of transmission does not change significantly. Futhermore,the band gap range of chirped photonic crystal diminishes gradually.

关键词：连续变频信号光子晶体折射材料晶体特征

Precipitates and Hydrogen Permeation Behavior in Vanadium-Bearing Microalloyed Low Carbon Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 290-295页

作者： xu Chun,li xiao-jie,SHEN Da-guang (Material Engineering Department,Shanghai Institute of Technology,Shanghai 200233,China) Shanghai Inst Technol Dept Mat Engn Shanghai 200233 Peoples R China

The precipitates and hydrogen permeation behavior were studied in the low carbon steel for *** the preparation of samples,Ti containing and Ti free in vanadium-bearing microalloyed low carbon steel heating at 750℃ for 3 h,were adopted after *** was found that the a large number of fine VC,TiC,TiN and Ti 4 C 2 S 2 precipitates were in samples of Vanadium-bearing microalloyed low carbon steel with Ti *** fine VC,Fe 3 C and MnS precipitates were in steels without Ti *** the numbers of precipitates in the former is more bigger than the *** activation energies for hydrogen diffusion in both samples are 26.5 and 23.7 kJ/mol,*** at 25℃,the effective diffusion coefficients in the samples for Ti containing and Ti free in Vanadium-bearing microalloyed low carbon steel were measured as 2.71×10-6 and 4.22×10-6 cm 2 /s,*** fishscaling defect occurred in the former and heavy fishscaling defect in the later.

关键词： precipitate hydrogen permeability enameling vanadium-bearing microalloyed low carbon steel

A Hypothesis: Excessive Fear Impairing the Kidney

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Psychosomatic Medicine Research 2020年第1期2卷 14-18页

作者： xiao-xu li Tianjin University of traditional Chinese Medicine TianjinChina

The theory of seven emotions in traditional Chinese medicine(TCM)holds that excessive joy impairs the heart,excessive anger impairs the liver,excessive contemplation impairs the spleen,excessive grief impairs the lung and excessive fear impairs the kidney,*** to TCM,kidney is the congenital essence of life and governs the reproduction through the hypothalamus a pituitary axis to complete an ovarian function of the *** important events reflects fear affects the reproductive *** deficiency rat model was induced successfully by the methods of using the cat to frighten the mouse and simulating the scene of cat catching rat to form panic *** experimental research on excessive fear impairing the kidney were carried ***,we put forward the medical hypothesis of Excessive fear impairing the kidney.

关键词： Traditional Chinese medicine Fear Kidney

Association between maternal gestational diabetes and allergic diseases in offspring:a birth cohort study

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World Journal of Pediatrics 2023年第10期19卷 972-982页

作者： Yu-Jing Chen li-Zi lin Zhao-Yan liu Xin Wang Shamshad Karatela Yu-xuan Wang Shan-Shan Peng Bi-Bo Jiang xiao-xu li Nan liu Jin Jing li Cai Department of Maternal and Child Health School of Public HealthSun Yat-Sen UniversityNo.74 Zhongshan Road 2Yuexiu DistrictGuangzhou 510080Guangdong ProvincePeople’s Republic of China Guangdong Provincial Engineering Technology Research Center of Environmental Pollution and Health Risk Assessment Department of Occupational and Environmental HealthSchool of Public HealthSun Yat-Sen UniversityGuangzhouPeople’s Republic of China Department of Nutrition School of Public HealthSun Yat-Sen UniversityGuangzhouPeople’s Republic of China Guangdong Provincial Key Laboratory of Food Nutrition and HealthSchool of Public HealthSun Yat-Sen UniversityGuangzhouPeople’s Republic of China Key Laboratory of Brain Cognition and Education SciencesMinistry of EducationGuangzhouChina Faculty of Health and Behavioural Sciences Pharmacy Australia Centre of ExcellenceUniversity of QueenslandWoolloongabbaQLDAustralia Global Health Research Center Duke Kunshan UniversityKunshanPeople’s Republic of China Department of Medical Statistics School of Public HealthSun Yat-Sen UniversityGuangzhouPeople’s Republic of China Institute for Brain Research and Rehabilitation South China Normal UniversityGuangzhouPeople’s Republic of China Institute of Tropical Health and Medicine(AITHM) James Cook UniversityTownsvilleQLDAustralia

Background Previous studies have linked gestational diabetes(GDM)with allergies in ***,the effect of specific glucose metabolism metrics was not well characterized,and the role of polyunsaturated fatty acids(PUFAs),a modifier of metabolism and the immune system,was *** aimed to investigate the association between maternal GDM and allergic diseases in children and the interaction between glucose metabolism and PUFAs on allergic *** This prospective cohort study included 706 mother–child dyads from Guangzhou,*** GDM was diagnosed via a 75-g oral glucose tolerance test(OGTT),and dietary PUFAs were assessed using a validated food frequency *** disease diagnoses and the age of onset were obtained from medical records of children within three years *** Approximately 19.4%of women had GDM,and 51.3%of children had any allergic *** was positively associated with any allergic diseases(hazard ratio[HR]1.40;95%confidence interval(CI)1.05–1.88)and eczema(HR 1.44;95%CI 1.02–1.97).A unit increase in OGTT after two hours(OGTT-2 h)glucose was associated with an 11%(95%CI 2%–21%)higher risk of any allergic diseases and a 17%(95%CI 1–36%)higher risk of food *** positive associations between OGTT-2 h glucose and any allergic diseases were strengthened with decreased dietary a-linolenic acid(ALA)and increased n-6 PUFAs,linoleic acid(LA),LA/ALA ratio,and n-6/n-3 PUFA *** Maternal GDM was adversely associated with early-life allergic diseases,especially *** were the first to identify OGTT-2 h glucose to be more sensitive in inducing allergy risk and that dietary PUFAs might modify the associations.

关键词： Allergic disease Cohort study Eczema Gestational diabetes Polyunsaturated fatty acid

Comparison of Undernutrition Prevalence of Children under 5 Years in China between 2002 and 2013

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Biomedical and Environmental Sciences 2016年第3期29卷 165-176页

作者： YU Dong Mei ZHAO li Yun YANG Zhen Yu CHANG Su Ying YU Wen Tao FANG Hong Yun WANG xun YU Dan GUO Qi Ya xu xiao li FANG Yue Hui ZHAO Wen Hua YANG xiao Guang DING Gang Qiang liANG xiao Feng National Center for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China United Nations Children's Fund Beijing 100600China Chinese Center for Disease Control and Prevention Beijing 102206China

Objective To describe the undernutrition status of children under 5-year in China, and study the trend between 2002 and 2013. Methods The study was based on two national surveys. Undernutrition was determined against WHO＇s 2006 growth standards. The prevalence in 2013 and 2002 was weighted by China sixth National Population Census （2010）. The relationship between undernutrition and gender/age groups/different areas use weighted logistic regression. Results The results indicated the overall prevalence of stunting, underweight, and wasting of Chinese children under S-year was 8.1%, 2.4%, and 1.9% in 2013, respectively. The prevalence of stunting was higher for children aged 12-47 month, while underweight was higher for children aged 48-59 month. The prevalence of undernutrition was higher in rural areas than in urban areas, especially in poor rural areas. There was a decline of stunting, underweight, and wasting between 2002 and 2013 among the children, with greater reduction in rural areas than in urban areas. Conclusion The prevalence of undernutrition of children under 5-year remains high in rural areas especially in poor rural areas in China. It is urgent to take action to control undernutrition in the vulnerable areas and subgroups.

关键词： Undernutrition Prevelence Children under 5