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Association between childhood obesity and gut microbiota:16S rRNA gene sequencing-based cohort study

World Journal of Gastroenterology 2024年第16期30卷 2249-2257页

作者： Xu-Ming Li Qing Lv Ya-Jun Chen Lu-biao yan Xin Xiong Laboratory Department Nanjing Medical University Affiliated Obstetrics and Gynecology Hospital(Nanjing Maternal and Child Health Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Shenzhen University General HospitalShenzhen 518055Guangdong ProvinceChina Department of Inspection Division Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Neonatology Chenzhou First People’s HospitalChenzhou 423000Hunan ProvinceChina

BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevention strategies for childhood obesity.Thirty normal-weight and thirty age-and sex-matched obese children were included.Questionnaires and body measurements were collected,and fecal samples underwent 16S rDNA sequencing.Significant differences in body mass index(BMI)and body-fat percentage were observed between the groups.Analysis of gut microbiota diversity revealed lowerα-diversity in obese children.Differences in gut microbiota composition were found between the two groups.Prevotella and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control group.AIM To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood obesity.METHODS Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,respectively.Basic information was collected through questionnaires and body measurements were obtained from both obese and normal-weight children.Fecal samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity analysis.RESULTS Significant differences in BMI and body-fat percentage were observed between the two groups.The Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson indices.Kruskal-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggesting substantial disparities in both the species

关键词： Childhood obesity Gut microbiota 16S rDNA sequencing Diversity analysis Genus identification Body mass index

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Crystallization Kinetics Study on Magnetron-Sputtered Amorphous TiA1 Alloy Thin Films

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Chinese Physics Letters 2014年第4期31卷 100-104页

作者： SHUI Lu-Yu yan biao School of Materials Science and Engineering Tongji University Shanghai 201804 Shanghai Key Lab of D&A for Metal-Functional Materials Shanghai 201804

Crystallization kinetics of magnetron-sputtered amorphous TiAl ahoy thin films is investigated by differential scanning calorimetry through isothermal analysis and non-isotherm analysis. In non-isothermai analysis, the Kissinger method and the Ozawa method are used to calculate the apparent activation energy and local activation energy, respectively, in the crystallization processes of amorphous TiA1 thin films. Furthermore, the crystallization mechanism is discussed from the investigation of the A vrami exponent by isothermal analysis. In addition, x-ray diffraction is utilized to reveal the grain orientation and evolution during the crystallization of TiA1 thin fihns.

关键词： Films Crystallization Kissinger

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Investigation of morphology selection for CBr_4-C_2Cl_6 alloy in three dimensions with multi-phase field method

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Science China(Physics,Mechanics & Astronomy) 2011年第5期54卷 866-871页

作者： yanG YuJuan yan biao School of Materials Science and Engineering Tongji UniversityShanghai 201804China Shanghai Key Lab of Development and Application for Metal Functional Materials Tongji UniversityShanghai 201804China

With the multi-phase field model, the unidirectional solidification with constant velocity growth and variable velocity growth of the CBr4-C2Cl6 eutectic alloy is simulated in three dimensions. The simulated results with constant velocity growth show that with the increase of pulling velocity, the morphology of the CBr4-C2Cl6 alloy evolves in the sequence of lamellar merging →lamellar-rod transition→stable lamellar growth→oscillating growth→lamellar branching. A morphology selection map is established with different pulling velocities, which is confirmed to be correct by the velocity change process. It is shown that all of the morphology transitions, the average interface growth velocity and average interface undercooling show a hysteresis effect against the instant of velocity change. The relationship between the interface average undercooling and interface average growth velocity is consistent with the theoretical value.

关键词：共晶合金 C2Cl6 形态多相位场方法尺寸凝固速度层状生长

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Al-Si-Cu-Ni合金梯度结构对弯曲性能的影响

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粉末冶金工业 2024年第3期34卷 40-45,53页

作者：史志朝严彪严鹏飞同济大学材料科学与工程学院上海201804 苏州开雷智能装备有限公司江苏苏州215332 上海市金属功能材料开发应用重点实验室上海201804 核工业第八研究所上海201800

通过改变选择性激光熔化成形过程中的激光功率,在不同工艺参数下制备了Al-Si-Cu-Ni梯度结构合金,测试了正压和反压条件下的弯曲性能。优化工艺参数后,提高了梯度结构合金的综合力学性能,观察其侧面不同位置处的微观组织结构,并测试了硬... 详细信息

通过改变选择性激光熔化成形过程中的激光功率,在不同工艺参数下制备了Al-Si-Cu-Ni梯度结构合金,测试了正压和反压条件下的弯曲性能。优化工艺参数后,提高了梯度结构合金的综合力学性能,观察其侧面不同位置处的微观组织结构,并测试了硬度分布。结果表明,在正压条件下的弯曲性能优于反压。随着激光功率的增大,显微组织逐渐粗化,富Cu、Ni第二相的析出数量增多,维氏硬度和布氏硬度线性降低,使得合金样品产生梯度结构。最佳工艺参数下制备的梯度结构合金在正压条件下的弯曲强度和断裂位移可达(838±22)MPa和(0.93±0.04)mm,显著高于均质结构合金((767±24)MPa、(0.85±0.03)mm),表明梯度结构对合金材料产生了强韧化作用,主要归因于细晶组织强度高,粗晶组织塑性好,二者的协同作用促进了合金的高强度和高韧性。

关键词：选择性激光熔化 Al-Si-Cu-Ni合金梯度结构弯曲性能微观组织结构

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Synthesis and characterization of water-soluble magnetite nanocrystals via one-step sol-gel pathway

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1239-1243页

作者： QI HongZhang yan biao LI ChengKui LU Wei School of Materials Science and Engineering Tongji UniversityShanghai 200092China Shanghai Key Laboratory of D&A for Metal-Functional Materials Shanghai 200092China

Water-soluble magnetite nanocrystals have been prepared by one-step non-alkoxide sol-gel method.The magnetic properties of magnetite nanocrystals obtained are size dependent.The experimental results also reveal that 2-pyrrolidone not only serves as solvent,but also involves surface coordination which renders the magnetite nanoparticles water-soluble and colloidal solution stable.Although the current synthetic approach is a small modification to the non-alkoxide sol-gel method,it allows us to directly obtain high-quality water-soluble magnetic nanocrystals.In addition,we realize that this method could be easily extended to preparation of many other transition and main group metal oxide water-soluble nanocrystals only from simple metal ion salts.

关键词：纳米晶体合成方法水溶性磁铁矿凝胶法溶胶单步表征

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Preparing Ca-P coating on biodegradable magnesium alloy by hydrothermal method:In vitro degradation behavior

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Chinese Science Bulletin 2012年第18期57卷 2319-2322页

作者： Li KaiKai Wang Bing yan biao Lu Wei School of Material Science and Engineering Tongji UniversityShanghai 201804China Shanghai Key Laboratory of D&A for Metal-Functional Materials Tongji UniversityShanghai 201804China

Magnesium alloys are potentially attractive biodegradable materials.However,their rapid corrosion rate limits their biomedical application.To slow down the rate of biodegradation,a protective calcium-phosphate coating was formed on a magnesium alloy substrate by a hydrothermal method.Scanning electron microscope results showed that the coating consisted of two layers with different crystalline characteristics.The loose outer layer showed a prism-like crystal structure,while the compact inner layer is a dense ultra-fine regular di-pyramid-like structure with an average grain dimension of ～200 nm.The compositions of the inner layer and outer layer were calcium-deficient hydroxyapatite (Ca-def HA) and dicalcium phosphate (DCPa),respectively.The coating adhered well to the substrate with a thickness of about 15 m.Immersion in Hank's solution indicated that the coating could significantly improve the degradation properties of magnesium alloy.The pH of the solution containing the coated samples increased much more slowly than the untreated control.After 8 d immersion,the uncoated sample had corroded seriously while the coated sample was much less corroded.The Ca/P atom ratio in both the layers of the coating increased and the coating was still protecting the substrate.The two layers of the coating corroded differently because of differences in solubility.The outer layer was more severely attacked and many holes were formed on the surface,the inner layer suffered less attack.In addition,a growth of precipitate on the inner layer was observed,indicating that surface bioactivity was improved by the coating.Thus,magnesium alloys coated with a Ca-P coating prepared by a hydrothermal method are promising candidate biodegradable biomaterials,and further investigation of in vivo degradation behavior is suggested.

关键词：降解行为镁合金水热法生物可降解镀层可生物降解材料涂层保护体外

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Study of local environment of Cu atoms in Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9 alloy with different annealing temperature

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Science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1887-1891页

作者： ZHANG Yu yanG Ying WANG YuXin LU Wei yan biao School of Materials Science and Engineering Tongji University Shanghai Key Lab. of D&A for Metal-Functional Materials Department of Chemical&Materials Engineering the University of AucklandPB 92019 Auckland 1142 New Zealand

The local environment of Cu atoms in Fe73.5Cu1Nb3Si13.5B9 alloy was investigated by extended X-ray absorption fine structure(EXAFS).Cu clusters began to order when the annealing temperature was around 733 K from the results of the Fourier transform curves.The fitting results showed that the first shell of the near fcc(face-centered cubic)Cu clusters only contained Cu atoms.The coordination number increased with the annealing temperature.Subsequently,the occupancy rate increased from 33.3%(annealed at 733 K)to 100% (annealed at 853 K).This local structural change of Cu atoms could probably affect the distribution of the bcc(body-centered cubic)α-Fe in Fe73.5Cu1Nb3Si13.5B9 alloy.

关键词：退火温度铜原子金合金扩展X射线吸收精细结构环境纳米晶软磁 EXAFS

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Electrochemical behaviour and cytocompatibility of nano-fluoridated apatite coating on biodegradable magnesium alloy by simple chemical conversion

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Science China(Technological Sciences) 2013年第1期56卷 80-83页

作者： LI KaiKai WANG Bing CHAI Jing yan biao LU Wei School of Materials Science and Engineering Tongji University Shanghai Key Laboratories of D&A for Metal-Functional Materials Tongji University

Magnesium and its alloys have attracted great attention as biocompatible and degradable biomaterials recent years.But their corrosion rate has been proved to be too high,which limits their biomedical application greatly.In order to improve the corrosion resistance,nano-fluoridated apatite(FA) coating was prepared on ZK60 magnesium alloy by a simple chemical conversion method.The FA coating showed a needle-like morphology.The polarization curves and EIS plots indicated that the FA coating improved the corrosion potential by 125 mV and doubled the polarization resistance of the magnesium alloy,meanwhile decreasing the corrosion current by two orders of magnitude of the substrate in simulated body fluid.The MTT assay indicated good cytocompatibility of L-929 cells with the fluoridated apatite coated magnesium alloy.

关键词： ZK60镁合金可降解生物材料电化学行为生物相容性纳米涂层氟磷灰石化学转化细胞相容性

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不同饱和度下膨胀土原位孔内剪切试验及强度响应特征

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岩土力学 2024年第1期45卷 153-163页

作者：罗晓倩孔令伟鄢俊彪高志傲田升奎中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 中国科学院大学北京100049 桂林理工大学广西岩土力学与工程重点实验室广西桂林541004

膨胀土强度随饱和度变化显著,非饱和膨胀土的抗剪强度一直是研究膨胀土工程问题的关键。选取南阳市某高速路沿线边坡膨胀土为研究对象,进行了天然条件下处于不同饱和度状态的膨胀土原位孔内剪切试验,获得了自然条件下膨胀土的抗剪强度... 详细信息

膨胀土强度随饱和度变化显著,非饱和膨胀土的抗剪强度一直是研究膨胀土工程问题的关键。选取南阳市某高速路沿线边坡膨胀土为研究对象,进行了天然条件下处于不同饱和度状态的膨胀土原位孔内剪切试验,获得了自然条件下膨胀土的抗剪强度随饱和度的变化特征。膨胀土的抗剪强度、黏聚力、内摩擦角随着膨胀土饱和度的增大而逐渐减小。结合现场试验数据和土-水特征曲线,提出了以法向应力、饱和度为变量和以法向应力、基质吸力为变量的两种非饱和膨胀土的抗剪强度计算模型,并结合试验数据对计算模型的适用性进行了验证。与之前常用的非饱和土抗剪强度计算模型相比较,提出的两种计算模型所需的拟合参数少,适用于更宽吸力范围、不同法向应力条件下非饱和膨胀土抗剪强度的计算,且结果更为准确。

关键词：非饱和膨胀土饱和度孔内剪切试验抗剪强度基质吸力计算模型

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Effects of Calcination Temperature on the Structure and Adsorption Performance of Ce-Mn/AC Materials

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Wuhan University Journal of Natural Sciences 2017年第5期22卷 435-442页

作者： GAO Wenwen ZHANG Zhifang CHEN Bi MA Xiangrong yan biao School of Chemistry and Chemical Engineering YulinUniversityYulin719000ShaanxiChina Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization Yulin UniversityYulin 719000ShaanxiChina

Activated carbon-supported bimetallic cerium-man- ganese （Ce-Mn/AC） materials were prepared by impregnation method to study the effect of calcination temperature on the structure and adsorption performance of absorbents. The obtained materials were characterized by using X-ray diffraction （XRD）, scanning electron microscope （SEM）, N2 adsorption-desorption iso- therm, Fourier transformed infrared （FT-IR）, and X-ray photoelectron spectroscopy （XPS）. As the results showed, the diffraction peaks of CeO2 decreased and even disappeared; Mn species were transformed from Mn3O4 to Mn2O3 on the surface of Ce-Mn/AC; the BET specific surface area increased first and then decreased on the elevating calcination temperature; the number of acid functions of AC was reduced after being modified by cerium and manganese All these changes were directly attributed to the synergistic effects between MnOx and CeO2. AC800 exhibited the best phenol adsorption capacity. The adsorption mechanism of phenol on Ce-Mn/AC was discussed with hydrophilic （hydrophobic） interaction and hard and soft acid-base theory.

关键词： calcination temperature cerium-manganese acti- vated carbon synergistic effect adsorption

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