检索结果-南通市图书馆

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第09期 43-59页

作者： Xu Pan wei Jiang Chuan Yue Shi-Jun Lei Yu-Xin Cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory Chinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China

The Very Large Area gamma-ray Space Telescope （VLAST） is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms, thus enabling the detection of photons with energies ranging from MeV to TeV. This project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector, a tracker detector that also serves as a low-energy calorimeter, and a high-energy imaging calorimeter. We developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance, including the effective area, angular resolution, and energy resolution, and explored specific optimizations of the detector configuration. Our simulation-based analysis indicates that the current design of the VLAST is physically feasible, with an acceptance above 10 m2sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2% at 10 GeV, and an angular resolution better than 0.2° at 10 GeV. The VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词：

冲破“顾拜旦陷阱”迷思:2024年巴黎奥运会与法国体育外交

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

武汉体育学院学报 2024年第7期58卷 7-16页

作者：魏伟尚希萌北京外国语大学国际新闻与传播学院北京100089 北京外国语大学国际体育传播与外交研究中心北京100089

2024年巴黎奥运会恰逢百年未有之大变局,同时处于国际奥委会实施战略变革“三部曲”的重要时期。研究梳理了法国自现代奥林匹克运动创建以来的体育外交发展,回顾了法国体育国际话语权的变迁过程。法国以2024年巴黎奥运会为契机,构建以... 详细信息

2024年巴黎奥运会恰逢百年未有之大变局,同时处于国际奥委会实施战略变革“三部曲”的重要时期。研究梳理了法国自现代奥林匹克运动创建以来的体育外交发展,回顾了法国体育国际话语权的变迁过程。法国以2024年巴黎奥运会为契机,构建以城市传播为核心的文化记忆场;同时积极布局体育外交,通过实施“新体育外交”战略提升国际影响力、文化软实力和体育国际话语权,并试图以崭新的体育地缘政治发展路线冲破“顾拜旦陷阱”的迷思。

关键词：体育外交 2024年巴黎奥运会法国新体育外交体育国际话语权顾拜旦陷阱体育地缘政治

维普期刊数据库博看期刊

Assessment of XAF1 as A Biomarker to Differentiate Hepatocellular Carcinoma from Nonneoplastic Liver Tissues

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Cancer Research 2012年第3期24卷 201-206页

作者： Ying lin wei Li Institute of Biological Sciences and Biotechnology Donghua UniversityShanghai 201620China Key Laboratory of Systems Biomedicine(Ministry of Education) Shanghai Center for Systems BiomedicineShanghai Jiaotong UniversityShanghai 200240China

Objective： XIAP-associated factor 1 （XAF1） expression has been shown to be related with apoptosis in hepatocellular carcinoma （HCC）. However, the correlation of XAF1 expression with HCC tumor grade has not been intensively assessed. XIAP-associated factor-1 （XAF1） is an important apoptosis inducer in human HCC. The aim of this study is to determine the correlation between XAF1 expression and HCC histopathological grades. Methods： The mRNA levels of XAF1 in 24 paired HCC-nonneoplastic specimens were quantified by real-time reverse transcription PCR （RT-PCR）. Protein levels of XAF1 in 110 paired HCC-noncancer tissues were investigated by immunostaining specimens on a tissue microarray （TMA）. Correlations between XAF1 mRNA levels or protein expression and clinicopathological features were assessed by statistical analysis. Results： Both XAF1 mRNA and protein were significantly under-expressed in HCC tissues compared to their non-neoplastic counterparts. No significant relationship was found between XAF1 mRNA or protein expression and histological tumor grade. Conclusion： All these data suggest that XAF1 is a potential biomarker for differentiating HCC with noncancerous tissues.

关键词： XAF1 Biomarker HCC Tumor grade Tissue microarray

Phosphatidylcholine protects against the hepatotoxicity of acrylamide via maintaining metabolic homeostasis of glutathione and glycerophospholipid

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2024年

作者： Yaoran Li wei Jia Yiju Zhang Yong Wu Li Zhu Jingjing Jiao Yu Zhang Department of Gastroenterology， the First Affiliated Hospital， Zhejiang University School of Medicine，Zhejiang Key Laboratory for Agro-Food Processing， College of Biosystems Engineering and Food Science， Zhejiang University Department of Gastroenterology， the First Affiliated Hospital， Zhejiang University School of Medicine， Zhejiang Key Laboratory for Agro-Food Processing， College of Biosystems Engineering and Food Science， Zhejiang University College of Food Science and Technology， Yunnan Agricultural University College of Chemistry and Life Sciences， Sichuan Provincial Key Laboratory for Development and Utilization of Characteristic Horticultural Biological Resources， Chengdu Normal University Department of Nutrition， School of Public Health， Department of Clinical Nutrition of Affiliated Second Hospital， Zhejiang University School of Medicine

Acrylamide is classified as a Class 2A carcinogen and mainly metabolized to produce hepatotoxicity. Phosphatidylcholine is thought to protect the liver from damage， but the protective role of phosphatidylcholine on acrylamide-exposed metabolic disorders remains unclear. We investigated protective effect of phosphatidylcholine on the hepatic metabolism in rats exposed to acrylamide using metabolomics and molecular biology approaches. Overall， 32 endogenous effect biomarkers and 4 exposure biomarkers were identified as differential signature metabolites responsible for acrylamide exposure and phosphatidylcholine protection. Acrylamide exposure interferes with glutathione metabolism by consuming antioxidant glutathione， cysteine and L-ascorbic acid， and disrupts lipid and carbohydrate metabolism through reducing carnitine content and increasing lipid peroxidation. The phosphatidylcholine treatment reduces the expression of cytochrome P450 2E1， alleviates the oxidative stress and inflammation of the liver， and stabilizes the content of glutathione， and thus alleviates the disorder of glutathione. Meanwhile， phosphatidylcholine shifted acrylamide-induced phosphatidylcholine into lysophosphatidylcholine to storage from lysophosphatidylcholine to diacylglycerol， thereby maintaining metabolic homeostasis of glycerophospholipid. The results suggested that phosphatidylcholine supplementation alleviate the disorder of glutathione and lipid metabolism caused by acrylamide exposure， but not significantly change the levels of mercapturic acid adducts of acrylamide， providing the evidence for phosphatidylcholine protection against acrylamide-induced liver injury.

关键词：

Peaches pulp(Prunus persica L.) mitigate type 2 diabetic mice by modulating of glucose metabolism and gut microbiota

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2024年

作者： Leyi Zhou Jianfen Ye Yingying wei Mouayche Salma Shu Jiang Yi Chen Xingfeng Shao State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products， Zhejiang-Malaysia Joint Research Laboratory for Agricultural Product Processing and Nutrition， College of Food Science and Engineering， Ningbo University

Peach are a fruit with high nutritional and economic value， but their safety and suitability for diabetic patients have been questioned. This study investigated the effects and potential mechanisms of peach pulp (PP) on type 2 diabetes mellitus (T2DM) in mice induced by a high-fat diet (HFD) combined with streptozotocin (STZ). The results showed that PP alleviated hyperglycemia， hyperlipidemia， hyperuricemia， and tissue dysfunction in T2DM mice through the synergistic effect of nutrients and non-nutrient compounds. Analysis of mRNA expression levels revealed that PP improved glucose metabolism in T2DM mice by promoting glycogen synthesis and inhibiting gluconeogenesis. Furthermore， elevated levels of PP resulted in an increase in acetic acid content following a 4 weeks intervention period. Additionally， it led to the restoration of gut microbiota balance by decreasing the Firmicutes/Bacteroidota (F/B) ratio and enhancing the presence of Romboutsia， Allobaculum， Alloprevotella， and Bacteroides after an 8 weeks intervention. Ultimately， our results suggest that PP may offer advantages for individuals with diabetes.

关键词：

Mechanical properties and cracking behaviors of limestone-like samples with two parallel fissures before and after grouting

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Central South University 2021年第9期28卷 2875-2889页

作者： LE Hui-lin wei Ji-hong SUN Shao-rui WANG Wu-chao FAN hao-tian School of Earth Science and Engineering Hohai UniversityNanjing 210098China

In the present work,uniaxial compressive tests were carried out on limestone-like samples containing two parallel open fissures or cement-infilled fissures with different *** property and crack behavior of limestone-like samples with two parallel open fissures or cement-infilled fissures were affected by bridge inclination angle and fissure inclination *** types of coalescence of rock bridge for samples containing open fissures or cement-infilled fissures were summarized and *** closure of tensile crack was observed in the samples with small fissure inclination *** is a new phenomenon which is not mentioned in previous *** results show that the peak strength,crack initiation stress,and coalescence type are different between open fissures and cement infilled *** reason for this phenomenon is that grouting of cement can transfer stress and reduce stress concentration at the flaw tip and rock bridge area.

关键词： cement-infilled fissure crack behavior compressive strength coalescence type

One-Pot Synthesis of Spiro[fluorene-9,9'-xanthene]Derivatives

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2021年第3期39卷 701-709页

作者： hao-Xuan Yuan Ying wei ling-Hai Xie wei Huang Centre for Molecular Systems and Organic Devices(CMSOD)&Key Laboratory for Organic Electronics and Information Displays&Institute of Advanced Materials(IAM)&Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM) Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjingJiangsu 210023China Shaanxi Institute of Flexible Electronics(SIFE) Northwestern Polytechnical University127 West Youyi RoadXi'anShaanxi 710072China

As a novel class of spirofluorenes,spirobifluorene(SBF)and spiro[fluo-rene-9,9'-xanthene]derivatives(SFXs)have orthogonal geometric config-uration,spiro-conjugation effect,and rigid steric hindrance,which can be widely used in the fields of synthetic chemistry,materials chemistry and supramolecular *** to their facile one-pot synthetic route,and to the variety of molecular designs,SFXs are expected to become new spiro functional materials that replace *** this review,we present the history,development and expansion of SFXs synthesis in one-pot methods,and the advantages and limitations of one-pot synthesis are also dis-cussed.

关键词： Spirofluorenes Spiro[fluorene 9,9'-xanthene]s(SFXs) One pot synthesis Synthetic methods Heterocycles Cyclization

Adsorption behaviors of strontium using macroporous silica based hexagonal tungsten oxide

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第5期59卷 601-608页

作者： Xiaoxia Zhang Yan Wu hao Wu Yuezhou wei School of Nuclear Science and Engineering Shanghai Jiao Tong University

A novel macroporous silica-based hexagonal tungsten oxide （h-WO3/SiO2） with exchangeable sodium cations located in hex- agonal tunnel structure was synthesized by a facile hydrothermal treatment of sodium tungstate dihydrate with 1 mol/L HCl solution. Utilization of the h-WO3/SiO2 adsorbent to remove aqueous strontium was investigated under the condition of various pH values, contact time, the initial concentration of metal ions, salt ion concentration, and coexisting ions. According to the experimental data, Sr2＋ adsorption equilibrium was achieved within 15 min in acidic solution, and the maximum removal ca- pacity of Sr2＋ occurred at pH 4. The kinetic adsorption of Sr2＋ on h-WO3/SiO2 was controlled by pseudo second-order model, and the saturated adsorption of Sr2＋ on h-WO3/SiO2 was better described by Langmuir and Redlich-Peterson isotherm models compared with the Freundlich isotherm model. The distribution coefficient of St2＋ was more than 2000 cm3/g in the presence of Ca2＋, Mg2＋, La3＋, and Eu3＋, indicating that the h-WO3/SiO2 showed excellent selectivity towards Sr2＋ in pH 4.

关键词： strontium hexagonal tungsten oxide macroporous silica-based support adsorption equilibrium kinetics

TDD reciprocity calibration for multi-user massive MIMO systems with iterative coordinate descent

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2016年第10期59卷 93-102页

作者： hao wei Dongming WANG Jiangzhou WANG Xiaohu YOU National Mobile Communications Research Laboratory Southeast University School of Engineering and Digital Arts University of Kent

For massive multiple-input multiple-output(MIMO) antenna systems, time division duplexing(TDD) is preferred since the downlink precoding matrix can be obtained through the uplink channel estimation,thanks to the channel reciprocity. However, the mismatches of the transceiver radio frequency(RF) circuits at both sides of the link make the whole communication channel non-symmetric. This paper extends the total least square(TLS) method to the case of self-calibration, where only the antennas of the access points(APs) are involved to exchange the calibration signals with each other and the feedback from the user equipments(UEs)is not required. Then, the proof of the equivalence between the TLS method and the least square(LS) method is presented. Furthermore, to avoid the eigenvalue decomposition required by these two methods to obtain the calibration coefficients, a novel algorithm named as iterative coordinate descent(ICD) method is *** analysis and simulation results show that the ICD method significantly reduces the complexity and achieves almost the same performance of the LS method.

关键词： TDD reciprocity calibration total least squares coordinate descent large-scale MIMO