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[Advances in molecular networking technology for discovering emerging contaminants and transformation products]

Se pu = Chinese journal of chromatography 2025年第1期43卷 33-42页

作者： xiao-mei tan Yu-Wei Zhang Zhao-Yu Jiao Nan-Yang Yu Si Wei State Key Laboratory of Pollution Control & Resource Reuse School of Environment Nanjing University Nanjing 210046 China.

Emerging contaminants and their transformation products are widely distributed in the environment. These pollutants carry unknown risks owing to their persistence, migration, and toxicity. The wide variety and complex structures of these substances render them difficult to identify using only target analysis. Suspect screening analysis can identify more substances than target analysis in a single run. However, this analysis method is based on limited data and cannot meet the growing demand for compound identification, especially for emerging contaminants and their transformation products with unknown information. The development of high-resolution mass spectrometry technology has promoted the applications of nontarget analysis in the environmental field, especially for identifying unknown transformation products. At present, the challenges of nontarget analysis include the difficulty of finding compounds of interest and their transformation products from complex data. Molecular networking calculates the similarity between mass spectra based on an improved cosine similarity algorithm. This method can cluster molecular families with similar structures, achieve visualization and a collection of massive mass spectral datasets, and promote the annotation of pollutants through networks and communities. Molecular networking can globally organize and systematically interpret complex tandem mass spectral datasets, providing a new direction for nontarget analysis. This technology was first used in proteomics and gradually introduced into metabolomics for the discovery of new natural products. Recently, it has been introduced into the environmental field for the study of various man-made chemicals, particularly for the discovery of emerging contaminants and their transformation products. In this paper, we introduce a molecular networking analysis method based on high-resolution tandem mass spectrometry and describe its applications in the nontargeted screening of emerging cont

关键词： emerging contaminants high-resolution tandem mass spectrometry molecular networking transformation products

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Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming Li Xi Chen mei-Ze Xu Tian Ding xiao-Ping Gong Zhuo-mei Li Xue-Yuan Liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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联合检测E-cadherin,VEGF表达水平在卵巢良恶性肿瘤诊断中的临床价值

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现代生物医学进展 2017年第20期17卷 3897-3900页

作者：唐晓梅刘坦坦张红娟王三喜敬源陕西省宝鸡市人民医院病理科陕西宝鸡721000 第四军医大学附属西京医院病理科陕西西安710032 陕西省宝鸡市人民医院妇科陕西宝鸡721000

目的:探讨联合检测E-钙粘素(E-cadherin)、血管内皮生长因子(VEGF)表达水平在卵巢良恶性肿瘤诊断中的临床价值。方法:收取2012年1月至2016年1月间我院收治的卵巢良恶性肿瘤患者共83例,使用免疫组化方法检测对E-cadherin及VEGF表达情况... 详细信息

目的:探讨联合检测E-钙粘素(E-cadherin)、血管内皮生长因子(VEGF)表达水平在卵巢良恶性肿瘤诊断中的临床价值。方法:收取2012年1月至2016年1月间我院收治的卵巢良恶性肿瘤患者共83例,使用免疫组化方法检测对E-cadherin及VEGF表达情况进行分析与比较。结果:E-cadherin在卵巢良性肿瘤、卵巢交界性肿瘤及卵巢恶性肿瘤中的阳性表达率分别为64.71%、44.44%及25.00%,VEGF在卵巢良性肿瘤、卵巢交界性肿瘤及卵巢恶性肿瘤中的阳性表达率分别为11.76%、33.33%及83.33%,上述差异均具有统计学意义(P0.05)。E-cadherin及VEGF表达呈负相关(r=-0.472,P<0.05)。结论:E-cadherin低表达及VEGF高表达与卵巢恶性肿瘤发生、发展及侵袭有密切关系。

关键词：卵巢良恶性肿瘤 E-钙粘素血管内皮生长因子诊断

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Transcriptional profile of gene clusters involved in the methylerythritol phosphate pathway in Bacillus subtilis 916

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Journal of Integrative Agriculture 2019年第3期18卷 644-655页

作者： xiao Ya-jing GAO tan-tan PENG Qi ZHANG Jie SUN Dong-mei SONG Fu-ping College of Life Science and Technology Heilongjiang Bayi Agricultural University State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural Sciences

The methylerythritol phosphate pathway is responsible for the biosynthesis of terpenoids, the largest class of secondary metabolites. Although the structures and functions of the proteins involved in this pathway have been well studied in Bacillus subtilis, only a few studies have reported the transcriptional profile of the genes involved. Therefore, we analyzed methylerythritol phosphate pathway genes in the genome of B. subtilis 916, which has been developed as a biological control agent against some rice diseases in China. Our results showed that methylerythritol phosphate pathway genes were distributed throughout the genome of this strain. These genes were transcribed during both the exponential and stationary phases. We further confirmed the transcription units of dxs, dxr, ispD, ispF, ipK, ispG, ispH, idi, and ispA in B. subtilis 916 through reverse transcription-PCR analyses; the results showed that these nine genes were located in seven different operons. The transcript start sites of the seven different operons were determined by 5′-rapid amplification of cDNA ends-PCR. Thus, our study provides a molecular basis at the transcriptional level for investigating homoterpene synthesis in the methylerythritol phosphate pathway of B. subtilis 916.

关键词： methylerythritol phosphate pathway transcription Bacillus subtilis biological control

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非静水压作用下石膏电学性质的理论研究

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原子与分子物理学报 2025年第6期42卷 129-135页

作者：周梅吴雷罗小松何宗润贵州民族大学物理与机电工程学院贵阳550025 重庆大学能源与动力工程学院重庆400044

地球内部广泛存在着差应力,这些外在因素的存在影响着矿物的性质,而矿物的电学性质与结构相变息息相关.为了更加了解地球内部结构与动力学过程,采用第一性原理方法,在等效平衡压0~10 GPa范围内计算地球内部浅层矿物石膏在静水压和非静... 详细信息

地球内部广泛存在着差应力,这些外在因素的存在影响着矿物的性质,而矿物的电学性质与结构相变息息相关.为了更加了解地球内部结构与动力学过程,采用第一性原理方法,在等效平衡压0~10 GPa范围内计算地球内部浅层矿物石膏在静水压和非静水压条件下的电学性质.计算结果表明:静水压和非静水压条件下无水石膏的密度和带隙变化基本一致,但二水石膏的密度和带隙在非静水压为6 GPa附近发生突变,这可能是由于非静水压环境使晶体结构更容易发生畸变,更有利于水分子氢键网络的重新排列和CaSO_(4)层间结构的塌缩,因此非静水压下可能更加有利于二水石膏在高温高压下的脱水反应.这对理解地幔中矿物的脱水和储水产生重大的影响,为理解地幔中矿物的脱氢和储水提供理论依据.

关键词：差应力石膏电学性质第一性原理

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Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng Hai-Hui Jiang Hui-Li Kang Yi Jiang Hua-Wei Zhang xiao-mei Song Yu-Ze Li Wen-Li Huang Dong-Dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

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Heat Capacity and Enthalpy of Fusion of Crystalline Pyrimethanil Decylate(C_(22)H_(33)N_3O_2)

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Chemical Research in Chinese Universities 2005年第6期21卷 697-701页

作者： SUN xiao-hong LIU Yuan-fa tan Zhi-cheng WANG mei-han JIA Ying-qi College of Chemical Engineering Chemical Research Institute Northwest University Xi＇an 710069 P. R. China Department of Chemistry Northwest University Xi＇an 710069 P. R. China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P. R. China

Low-temperature heat capacities of pyrimethanil decylate （ C22 H33 N3 O2 ） were precisely measured with an automated adiabatic calorimeter over the temperature range from 78 to 373 K. The sample was observed to melt at （311.04 ± 0.06） K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be（45876± 12） J/mol, （147. 50 ±0. 05） J. mol^-1 · K^-1 and （99. 21 ±0. 03）% （mass fraction）, respectively. The extrapolated melting temperature for the absolutely pure compound obtained from fractional melting experiments is （311. 204±0. 035 ） K.

关键词： Pyrimethanil decylate Heat capacity Adiabatic calorimetry DSC

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The Products of Three Theta Functions and the General Cubic Theta Functions

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1115-1124页

作者： xiao mei YANG Department of Mathematics East China Normal University Shanghai 200241 P. R. China

In this paper we establish two theta function identities with four parameters by the theory of theta functions. Using these identities we introduce common generalizations of Hirschhorn-Garvan-Borwein cubic theta functions, and also re-derive the quintuple product identity, one of Ramanujan＇s identities, Winquist＇s identity and many other interesting identities.

关键词： Jacobi theta function quintuple product identity Winquist's identity Ramanujan identity

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Sperm DNA damage has a negative effect on early embryonic development following in vitro fertilization

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Asian Journal of Andrology 2018年第1期20卷 75-79页

作者： Wei-Wei Zheng Ge Song Qi-Ling Wang Shan-Wen Liu xiao-Li Zhu Shun-mei Deng An Zhong Yu-mei tan Ying tan Reproductive Medicine Center Family Planning Research Institute of Guangdong Province Guangzhou 510060 China Key Laboratory of Male Reproductive and Genetics Family Planning Research Institute of Guangdong Province Guangzhou 510060 China

Sperm DNA damage is recognized as an important biomarker of male infertility. To investigate this, sperm DNA damage was assessed by the sperm chromatin dispersion （SCD） test in semen and motile spermatozoa harvested by combined density gradient centrifugation （DGC） and swim-up in 161 couples undergoing in vitro fertilization （IVF）. Semen analysis and sperm DNA damage results were compared between couples who did or did not achieve pregnancy. The sperm DNA damage level was significantly different between the two groups （P 〈 0.05） and was negatively correlated with IVF outcomes. Logistic regression analysis confirmed that it was an independent predictor for achieving clinical pregnancy. The effects of different levels of sperm DNA damage on IVF outcomes were also compared. There were significant differences in day 3 embryo quality, blastocyst formation rate, and implantation and pregnancy rates （P 〈 0.05）, but not in the basic fertilization rate between the two groups. Thus, sperm DNA damage as measured by the SCD appears useful for predicting the clinical pregnancy rate following IVF.

关键词： DNA damage in vitro fertilization pregnancy outcome sperm

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FHA2 is a plant-specific ISWI subunit responsible for stamen development and plant fertility^FA

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Journal of Integrative Plant Biology 2020年第11期62卷 1703-1716页

作者： Bo-Wen Gu Lian-mei tan Cui-Jun Zhang xiao-mei Hou Xue-Wei Cai She Chen Xin-Jian He College of Life Sciences Beijing Normal UniversityBeijing 100875China National Institute of Biological Sciences Beijing 102206China Tsinghu a Institute of Multidisciplinary Biom edical Research Tsinghua UniversityBeijing 10084China

Imitation Switch(ISWI)chromatin remodelers are known to function in diverse multi-subunit complexes in yeast and ***,the constitution and function of ISWI complexes in Arabidopsis thaliana remain *** this study,we identified forkheadassociated domain 2(FHA2)as a plant-specific subunit of an ISWI chromatin-remodeling complex in *** in vivo and in vitro analyses,we demonstrated that FHA2 directly binds to RLT1 and RLT2,two redundant subunits of the ISWI complex in *** stamen filament is shorter in the fha2 and rlti/2 mutants than in the wild type,whereas their pistil lengths are *** shorter filament,which is due to reduced cell size,results in insufficient pollination and reduced *** rlt1/2 mutant shows an early-floweringphenotype,whereas the phenotype is not shared bythe fha2 *** with the functional specif-icity of FHA2,our RNA-seq analysis indicated that thefha2 mutant affects a subset of RLT1/2-regulated genesthat does not include genes involved in the regulation offlowering *** study demonstrates that FHA2functions as a previously uncharacterized subunit of theArabidopsis ISwI complex and is exclusively involved inregulating stamen development and plant fertility.

关键词： plant Arabidopsis shorter

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