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Key Properties of Solar Chromospheric Line Formation Process

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Chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 71-80页

作者： Zhong－QuanQu zhixu YunnanObservatory ChineseAcademyofSciencesKunming650011 NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

The distribution or wavelength-dependence of the formation regions of frequently used solar lines, Hα, Hβ, CaIIH and Car18542, in quiet Sun, faint and bright flares is explored in the unpolarized case. We stress four aspects characterising the property of line formation process: 1) width of line formation core; 2) line formation region; 3) influence of the temperature minimum region; and 4) wavelength ranges within which one can obtain pure chromospheric and photospheric filtergrams. It is shown that the above four aspects depend strongly on the atmospheric physical condition and the lines used. The formation regions of all the wavelength points within a line may be continuously distributed over one depth domain or discretely distributed because of no contribution coming from the temperature minimum region, an important domain in the solar atmosphere that determines the distribution pattern of escape photons. Cm the other hand, the formation region of one wavelength point may cover only one heigh t range or spread over two domains which are separated again by the temperature minimum region. Different lines may form in different regions in the quiet Sun. However, these line formation regions become closer in solar flaring regions. Finally, though the stratification of line-of-sight velocity can alter the position of the line formation core within the line band and result in the asymmetry of the line formation core about the shifted line center, it can only lead to negligible changes in the line formation region or the line formation core width. All these results can be instructive to solar filtering observations.

关键词： line: formation - radiative transfer - Sun: chromosphere

Ha Line Polarization in the 2B/X4.8 Flare of 2002 July 23

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Chinese Journal of Astronomy and Astrophysics 2003年第3期3卷 266-276页

作者： zhixu N.M.Firstova DepartmentofAstronomy NanjingUniversityNanjing210093 InstituteofSolar-TerrestrialPhysics RussianAcademyofSciencesSiberianDivisionRussia

On 2002 July 23, a 2B/X4.8 flare was observed in the Hα line spec-tropolarimetrically by the Large Solar Vacuum Telescope of Baikal AstrophysicalObservatory. Linear polarization of 3%-10% was detected in the Hα line, particu-larly where the line showed central reversal. The linear polarization is mainly radialon the solar disk and appears at the impulsive phase of the hard X-ray and γ-raybursts. It is limited to some relatively small regions of the flare. The polarizationin a limited small region (～ 4″ - 5″) changed its direction within a short period oftime (～ 10s).

关键词： Polarization - line: profile - Sun: flare

Meta-analysis of intraperitoneal chemotherapy for gastric cancer

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World Journal of Gastroenterology 2004年第18期10卷 2727-2730页

作者： Da-zhixu You-QingZhan Xiao-WeiSun Su-MeiCao Qi-RongGeng DepartmentofAbdominalSurgery CancerCenterSunYat-senUniversityGuangzhou510060GuangdongProvinceChina DepartmentofNasopharyngealCancer DepartmentofClinicalEpidemiologyCancerCenterSunYat-senUniversityGuangzhou510060GuangdongProvinceChina DepartmentofMedicalOncology CancerCenterSunYat-senUniversityGuangzhou510060GuangdongProvinceChina

AIM: To assess the efficacy and safety of intraperitoneal chemotherapy in patients undergoing curative resection for gastric cancer through literature ***: Medline (PubMed) (1980-2003/i), Embase(1980-2003/1), Cancerlit Database (1983-2003/1) and Chinese Biomedicine Database (1990-2003/1) were searched. Language was restricted to Chinese and *** statistical analysis was performed by RevMan4.2 software provided by the Cochrane Collaboration. The results were expressed with odds ratio for the categorical ***: Eleven trials involving 1 161 cases were *** pooled odds ratio was 0.51, with a 95% confidence interval (0.40-0.65). Intraperitoneal chemotherapy may benefit the patients after curative resection for locally advanced gastric cancer, and the combination of intraperitoneal chemotherapy with hyperthermia or activated carbon particles may provide more benefits to patients due to the enhanced antitumor activity of drugs. Sensitivity analysis and fail-safe number suggested that the result was comparatively ***, of 11 trials, only 3 studies were of high ***: Intraperitoneal chemotherapy after curative resection for locally advanced gastric cancer may be beneficial to patients. Continuous multicenter, randomized,double blind, rigorously designed trials should be conducted to draw definitive conclusions.

关键词： Meta-分析腹膜腔化学疗法胃肿瘤消化系统

Relevance between abutment pressure and fractal dimension of crack network induced by mining

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International Journal of Mining Science and Technology 2013年第6期23卷 925-930页

作者： Gao Mingzhong Jin Wencheng Dai zhixu Xie Jing State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University College of Hydraulic and Hydropower Engineering Sichuan University Energy&Chemical Industry Research Institute Shenma Group of Pingdingshan Coal Group College of Architecture and Environment Sichuan University

Based on the geological conditions of coal mining face No.15-14120 at No.8 mine of Pingdingshan coal mining group,the real-time evolution of coal-roof crack network with working face advancing was collected with the help of intrinsically safe borehole video *** according to the geology of this working face,a discrete element model was calculated by *** in situ experimental data with numerical results,the relationship between the fractal dimension of boreholes'wall and the distribution of advanced abutment pressure was studied under the condition of mining *** results show that the variation tendency of fractal dimension and the abutment pressure has the same characteristic *** distance between working face and the peak value of the abutment pressure has a slight increasing trend with the advancing of *** the working face is set as the original point,the trend of fractal dimension from the far place to the origin can be divided into three phases:constant,steady increasing and *** the turning points of these phases are the max-influencing distance(50 m)and peak value(15 m)of abutment pressure.

关键词： Boreholes Coal mines Cracks Finite difference method Fractal dimension

Acoustic emission from gas-filled coal under triaxial compression

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International Journal of Mining Science and Technology 2012年第6期22卷 775-778页

作者： Yin Guangzhi Qin Hu Huang Gun Lv Youchang Dai zhixu State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Chongqing University College of Resource and Environmental Sciences Chongqing University Gas Research Institute Energy and Chemical Research InstituteZhongping Energy and Chemical Group

Acoustic emission(AE) experiments have been performed on gas-saturated coal specimens under conventional triaxial *** AE characteristics were investigated for a methane gas flow through the coal *** AE parameter,AE count,when normalized by the total count number was used to represent the damage evolution in the gassy *** is shown that this AE parameter is a reasonable indicator for damage occurring within the coal specimen since its envelope has almost the same shape as the complete stress-strain curve,except for a short time *** addition,the change in AE count is highly consistent with the change in coal *** results also show that methane containing coal emits a small number of AE events before entering the yield *** activity gradually increases during the yield process up to the peak *** lowest permeability corresponds to the highest AE activity,implying failure will soon *** AE based constitutive model was constructed and the theoretical results agree well with those of experiments.

关键词： Rock mechanics Conventional triaxial compression Failure process Permeability Acoustic emission

High-temperature dielectric switch and second harmonic generation integrated in a stimulus responsive material

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Chinese Chemical Letters 2021年第1期32卷 539-542页

作者： Yingsong Xue zhixu Zhang Pingping Shi Wanying Zhang Qiong Ye Dawei Fu Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjing 211189China

Stimulus re s ponsive materials can provide a variety of desirable properties in one equipment unit,such as optoelectronic devices,data communications,actuators,memories,sensors and ***,it remains a large challenge to design such stimulus responsive materials,especially functional materials having both dielectric switch and second harmonic generation(SHG).Here,a new stimuli-responsive switchable material [(CH_(3))_(3)N(CH_(2))_(2)Cl]_(2)]Mn(SCN)_(4)(H_(2)O)_(2)] was discovered as a potential secondharmonic generation(SHG) dielectric *** is worth noting that it has SHG characteristics before and after undergoing reversible high-temperature phase *** this work,we successfully refined the tetramethylammonium cation to obtain a quasi-spherical cation,which is tetramethylchloroethylamine(TMCEM) *** substituting H with a halogen,the increased steric hindrance of the molecular makes energy barrier increased,resulting in the reversible high-temperature phase *** the same time,the interactions of quasi-spherical cations and [Mn(SCN)_(4)(H_(2)O)_(2)]^(2-) anions affect a noncentrosymmetric structure to induce the SHG *** findings provide a new approach to design novel functional switch materials.

关键词： Dielectric switch Second harmonic generation High-temperature Phase transition Stimulus responsive material

Bile acid coordinates microbiota homeostasis and systemic immunometabolism in cardiometabolic diseases

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Acta Pharmaceutica Sinica B 2022年第5期12卷 2129-2149页

作者： Baoyi Guan Jinlin Tong Haiping Hao zhixu Yang Keji Chen Hao Xu Anlu Wang Xiyuan Hospital China Academy of Chinese Medical SciencesBeijing 100091China National Clinical Research Center for Chinese Medicine Cardiology Beijing 100091China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Cardiometabolic disease(CMD), characterized with metabolic disorder triggered cardiovascular events, is a leading cause of death and disability. Metabolic disorders trigger chronic low-grade inflammation, and actually, a new concept of metaflammation has been proposed to define the state of metabolism connected with immunological adaptations. Amongst the continuously increased list of systemic metabolites in regulation of immune system, bile acids(BAs) represent a distinct class of metabolites implicated in the whole process of CMD development because of its multifaceted roles in shaping systemic immunometabolism. BAs can directly modulate the immune system by either boosting or inhibiting inflammatory responses via diverse mechanisms. Moreover, BAs are key determinants in maintaining the dynamic communication between the host and microbiota. Importantly, BAs via targeting Farnesoid X receptor(FXR) and diverse other nuclear receptors play key roles in regulating metabolic homeostasis of lipids, glucose, and amino acids. Moreover, BAs axis per se is susceptible to inflammatory and metabolic intervention, and thereby BAs axis may constitute a reciprocal regulatory loop in metaflammation. We thus propose that BAs axis represents a core coordinator in integrating systemic immunometabolism implicated in the process of CMD. We provide an updated summary and an intensive discussion about how BAs shape both the innate and adaptive immune system, and how BAs axis function as a core coordinator in integrating metabolic disorder to chronic inflammation in conditions of CMD.

关键词： Bile acid Nuclear receptors Cardiometabolic diseases Systemic immunometabolism Therapeutic opportunities

Down-regulation of γ-synuclein in human esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2003年第9期9卷 1900-1903页

作者： Cui-QiZhou ShuangLiu Li-YanXue Yi-HuaWang Hong-XiaZhu NingLu Ning-zhixu LaboratoryofCellandMolecularBiology CancerInstituteandCancerHospitalChineseAcademyofMedicalSciencesPekingUnionMedicalCollegeBeiiing100021.China DepartmentofPathology CancerInstituteandCancerHospitalChineseAcademyofMedicalSciencesPekingUnionMedicalCollegeBeijing100021China

AIM: To investigate gene expression pattern of human γsynuclein gene in human esophageal squamous cell carcinoma (ESCC) by using semi-quantitive reverse transcription polymerase chain reaction (RT-PCR), and to study the role of γ-synudein in the development of human ***: Semi-quantitive RT-PCR of 27 pairs of specimens of human ESCC tissues and corresponding normal tissues was used to investigate the expression pattern of γsynuclein in ESCC. 9706/γ-syn cells in which γ-synuclein was overexpressed were obtained through cloning γ-synuclein gene by PCR and transfecting it into ESCC 9706 cells, then selecting with G-418 for 14 days. The biological effects of γsynuclein were measured and compared between 9706/γ-syn and 9706/vec cells by cell growth curve and soft agar ***: RT-PCR showed that γ-synuclein gene was expressed in all the 27 cases of normal epithelial tissues,while downregulation of γ-synudein was observed in 16 out of the 27 cases (59.3%) of ESCC. There were also 6 cases of ESCC tissues with a high expression level of γ-synuclein mRNA. In functional analysis we found that over-expression of γ-synuclein in ESCC 9706 cells could inhibit the growth rate and transformation ability of ESCC 9706 ***: The low expression level of γ-synuclein in human ESCC and the biological effects of γ-synuclein overexpression on ESCC 9706 cells suggest that γ-synuclein may play a role as a negative regulator in the development of human ESCC.

关键词：食道癌磷状细胞癌逆转录聚合酶链反应 γ-synuclein

Detection of human papillomavirus in Chinese esophageal squamous cell carcinoma and its adjacent normal epithelium

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World Journal of Gastroenterology 2003年第6期9卷 1170-1173页

作者： Xiao-BoZhou MeiGuo Lan-PingQuan WeiZhang Zhe-MingLu Quan-HongWang YangKe Ning-zhixu LaboratoryofCellandMolecularBiology CancerInstitute&CancerHospitalChineseAcademyofMedicalSciencesBeiiing100021China LaboratoryofGenetics BeijingInstituteforCancerResearchSchoolofOncologyPekingUniversityNo.1DaHongLuoChangStBeiiing100034China DepartmentofPathology theThirdPeople'sHospitalofShanxiProvinceTaiyuan030013China

AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in ***: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene.RESULTS: There were approximately 64 % (31/48) patients having HPV-16 DNA in tumor samples, among them nearly twothirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7 % (8/23) and 26.1% (6/23) *** addition, at protein level detected by IHC assay, 27.1% (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found ***: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.

关键词：人乳头瘤病毒食管癌鳞癌食管上皮细胞病因学