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Quantification of choline concentration following liver cell apoptosis using ~1H magnetic resonance spectroscopy

World Journal of Gastroenterology 2012年第10期18卷 1130-1136页

作者： Zhi-Wei Shen zhen Cao Ke-Zeng You Zhong-xian Yang Ye-Yu xiao xiao-Fang Cheng Yao-Wen Chen Ren-Hua Wu Department of Medical Imaging The Second Affiliated Hospital Shantou University Medical College Shantou 515041 Guangdong Province China Central Laboratory Shantou University Shantou 515041 Guangdong Province China Provincial Key Laboratory of Medical Molecular Imaging Shantou 515041 Guangdong Province China

AIM: To evaluate the feasibility of quantifying liver choline concentrations in both normal and apoptotic rabbit livers in vivo, using 1H magnetic resonance spectroscopy (1H-MRS). METHODS: 1H-MRS was performed in 18 rabbits using a 1.5T GE MR system with an eight-channel head/neck receiving coil. Fifteen rabbits were injected with sodium selenite at a dose of 10 μmol/kg to induce the liver cell apoptosis. Point-resolved spectroscopy sequencelocalized spectra were obtained from 10 livers once before and once 24 h after sodium selenite injection in vivo. T1 and T2 relaxation time of water and choline was measured separately in the livers of three healthy rabbits and three selenite-treated rabbits. Hematoxylin and eosin and dUTP-biotin nick end labeling (TUNEL) staining was used to detect and confirm apoptosis. Choline peak areas were measured relative to unsuppressed water using LCModel. Relaxation attenuation was corrected using the average of T1 and T2 relaxation time. The choline concentration was quantified using a formula, which was tested by a phantom with a known concentration. RESULTS: Apoptosis of hepatic cells was confirmed by TUNEL assay. In phantom experiment, the choline concentration (3.01 mmol/L), measured by 1H-MRS, was in good agreement with the actual concentration (3 mmol/L). The average T1 and T2 relaxation time of choline was 612 ± 15 ms and 74 ± 4 ms in the control group and 670 ± 27 ms and 78 ± 5 ms in apoptotic livers in vivo, respectively. Choline was quantified in 10 rabbits, once before and once after the injection with sodium selenite. The choline concentration decreased from 14.5 ± 7.57 mmol/L before sodium selenite injection to 10.8 ± 6.58 mmol/L (mean ± SD, n = 10) after treatment (Z = -2.395, P < 0.05, two-sample paired Wilcoxon test). CONCLUSION: 1H-MRS can be used to quantify liver choline in vivo using unsuppressed water as an internal reference. Decreased liver choline concentrations are found in sodium selenite-treated rabbits unde

关键词： Cell apoptosis Magnetic resonance spectroscopy Quantification Choline In vivo

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Nanoencapsulation of hexavalent chromium with nanoscale zero-valent iron:High resolution chemical mapping of the passivation layer

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Journal of Environmental Sciences 2018年第5期30卷 4-13页

作者： xiao-yue Huang Lan Ling Wei-xian Zhang State Key Laboratory for Pollution Control College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Solid phase reactions of Cr（Ⅵ） with Fe（0） were investigated with spherical-aberration-corrected scanning transmission electron microscopy（Cs-STEM） integrated with X-ray energy-dispersive spectroscopy（XEDS）. Near-atomic resolution elemental mappings of Cr（Ⅵ）–Fe（0） reactions were acquired. Experimental results show that rate and extent of Cr（Ⅵ） encapsulation are strongly dependent on the initial concentration of Cr（Ⅵ） in solution. Low Cr loading in nZⅥ（〈1.0 wt%） promotes the electrochemical oxidation and continuous corrosion of n ZⅥ while high Cr loading（〉1.0 wt%） can quickly shut down the Cr uptake. With the progress of iron oxidation and dissolution, elements of Cr and O counter-diffuse into the nanoparticles and accumulate in the core region at low levels of Cr（Ⅵ）（e.g., 〈 10 mg/L）. Whereas the reacted n ZⅥ is quickly coated with a newly-formed layer of 2–4 nm in the presence of concentrated Cr（Ⅵ）（e.g., 〉 100 mg/L）. The passivation structure is stable over a wide range of pH unless pH is low enough to dissolve the passivation layer. X-ray photoelectron spectroscopy（XPS） depth profiling reconfirms that the composition of the newly-formed surface layer consists of Fe（Ⅲ）–Cr（Ⅲ）（oxy）hydroxides with Cr（Ⅵ） adsorbed on the outside surface. The insoluble and insulating Fe（Ⅲ）–Cr（Ⅲ）（oxy）hydroxide layer can completely cover the n ZⅥ surface above the critical Cr loading and shield the electron transfer. Thus, the fast passivation of nZⅥ in high Cr（Ⅵ） solution is detrimental to the performance of nZⅥ for Cr（Ⅵ） treatment and remediation.

关键词： Nanoscale zero-valent iron (nZVI) Hexavalent chromium Solid phase reaction Passivation Spherical-aberration-correctedscanning transmission electronmicroscopy (Cs-STEM)

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Corrosion behavior and failure mechanism of SiC whisker and c-AlPO_(4) particle-modified novel tri-layer Yb_(2)Si_(2)O_(7)/mullite/SiC coating in burner rig tests

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Journal of Advanced Ceramics 2022年第12期11卷 1901-1917页

作者： Pengju CHEN Peng xiao xian TANG Yang LI School of Nuclear Science and Technology University of South ChinaHengyang 421001China Powder Metallurgy Research Institute Central South UniversityChangsha 410083China National Key Laboratory of Science and Technology on High-strength Structural Materials Central South UniversityChangsha 410083China

The corrosion behavior of environmental barrier coatings(EBCs)directly affects the service life and stability of ceramic matrix composite(CMC)structural parts in the *** silicon carbide(SiC)whisker toughening phase and c-AlPO_(4) bonding phase are firstly used to improve the service life of novel tri-layer Yb_(2)Si_(2)O_(7)/mullite/SiC EBCs in the burner rig *** formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating caused the failure of coating at 1673 *** SiC whiskers in mullite middle coating significantly inhibited the formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating,and efficiently prevented the oxidation of carbon fiber reinforced silicon carbide(C_(f)/SiC)samples for 360-min thermal cycles(24 times)with a weight loss of 6.19×10^(−3) g·cm^(−2).Although c-AlPO_(4) particles further improved the service life of SiC_(w)-mullite(SM)coating,the overflow of PO_(x) gas aggravated the formation and expansion of cracks in the Yb_(2)Si_(2)O_(7) outer coating,and caused the service life of overall Yb_(2)Si_(2)O_(7)/c-AlPO_(4)-SiC_(w)-mullite(ASM)/SiC coating to be slightly lower than that of Yb_(2)Si_(2)O_(7)/SM/SiC *** study guides the design of modified tri-layer EBCs with long service life in high-temperature and high-speed gas environment.

关键词： Yb_(2)Si_(2)O_(7) mullite tri-layer sol-gel burner rig test

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Infinitely Many Solutions for a Class of Quasi-linear Elliptic Problem

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 728-743页

作者： xiao-yao JIA zhen-luo LOU School of Economics and Management Zhongyuan University of TechnologyZhengzhou 450007China Mathematics and Statistics School Henan University of Science and TechnologyLuoyang 471023China

In this paper,we study the following quasi-linear elliptic equation:■where Ω?R^(N) is a bounded domain,λ>0 is a *** function ψ(|t|)t is the subcritical term,and φ(|t|)t is the critical Orlicz-Sobolev growth term with respect to φ.Under appropriate conditions on φ,ψ and φ,we prove the existence of infinitely many weak solutions for quasi-linear elliptic equation,for λ∈(0,λ_(0)),where λ_(0)> 0 is a fixed constant.

关键词： quasi-linear elliptic equations variational methods Orlicz-Sobolev spaces

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K→πvv:New Contributions from Unit-Charged Scalars in Topcolor-Assisted Technicolor Models

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Chinese Physics Letters 1999年第10期16卷 712-714页

作者： xiao zhen-jun Department of Physics He’nan Normal UniversityXinxiang 453002 Department of Physics Peking UniversityBeijing 100871

We calculate the new contributions to the rare K-decays K^(+)→π^(+)vv and K_(L)→π^(0)vv from the unit-charged scalars appearing in the topcolor-assisted technicolor *** using the square-root ansatz for the mixing matrices D_(L)and D_(R),we find that:(a)the new contributions from top-pionsπ^(~±)and b-pions^(~H±)dominate over that from ordinary technipionsπ1 andπs;(b)for aR^(ts*)aR^(td)=-1/4,the enhancements to the ratios B(K^(+)→π^(+)vv)and B(K_(L)→π^(0)vv)from new scalars can be as large as a factor 7 and 11,respectively;(c)the theoretical predictions are still consistent with the data after including the new contributions.

关键词： ordinary contributions mixing

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Ince-Strutt Stability Charts for Ship Parametric Roll Resonance in Irregular Waves

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China Ocean Engineering 2017年第4期31卷 447-457页

作者： ZHANG xiao YANG He-zhen xiao Fei XU Pei-ji National Key Laboratory on Ship Vibration &Noise China Ship Development and Design Center State Key Laboratory of Ocean Engineering School of Naval Architecture.Ocean and Civil EngineeringShanghai Jiao Tong University School of Civil and Environmental Engineering Nanyang Technological University

Ince-Strutt stability chart of ship parametric roll resonance in irregular waves is conducted and utilized for the exploration of the parametric roll resonance in irregular waves. Ship parametric roll resonance will lead to large amplitude roll motion and even wreck. Firstly, the equation describing the parametric roll resonance in irregular waves is derived according to Grim’s effective theory and the corresponding Ince-Strutt stability charts are obtained. Secondly, the differences of stability charts for the parametric roll resonance in irregular and regular waves are compared. Thirdly, wave phases and peak periods are taken into consideration to obtain a more realistic sea condition. The influence of random wave phases should be taken into consideration when the analyzed points are located near the instability boundary. Stability charts for different wave peak periods are various. Stability charts are helpful for the parameter determination in design stage to better adapt to sailing condition. Last, ship variables are analyzed according to stability charts by a statistical approach. The increase of the metacentric height will help improve ship stability.

关键词： parametric instability parametric rolling multi-frequency irregular waves Ince-Strutt stability chart

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Effects of Sequence Distribution and Physical Aging on Physical Properties of PES/PEES Random, Block, and Alternative Copolymers

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Chemical Research in Chinese Universities 2006年第6期22卷 787-791页

作者： ZHOU xiao-ming JIANG zhen-hua Alan G. MacDiarmid Lab College of Chemistry Jilin University Changchun 130012 P. R. China

The random, block, and alternative copolymers of poly ether sulfone（PES） and poly ether ether sulfone（PEES） were synthesized v/a three kinds of methods. The chemical structures of the three kinds of copolymers were characterized by ^13C NMR. Three kinds of PES/PEES copolymers（ Tg =215 ℃ ）, which were almost identical in composition but different in sequence distribution, were used. Their physical aging process was studied by differential scanning calorimetry（DSC） at three aging temperatures ranging between Tg -15 ℃ and Tg -25℃. The experimental results reveal that the alternative copolymer shows a lower enthalpy relaxation time 〈T〉 and apparent activation energy when compared with the random and block copolymers. The result of the electron-microscopy investigation of the three copolymers that were treated at 200 ℃ for 96 h indicates that the molecular aggregation of the copolymers changed from a randomly coiled amorphous phase to an ordered phase, and the ordered structure of the alternative copolymer was more distinct than that of the random phase. The experimental results of this study suggest that the motion of the sagments is affected by the different molecular-chain sequence distribution.

关键词： Physical aging Apparent activation energy Sequence distribution

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Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 13-21页

作者： xian-Rong Wu xiao-Hong He Yong-Fang Xie School of Life Health Information Science and Engineering Chongqing Post and Communications UniversityChongqing 400065China

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various *** recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus *** dysbiosis may promote the formation and recurrence of *** microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these *** the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut *** microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

关键词： Recurrent colorectal polyps Gut microbiota dysbiosis Klebsiella Probiotics Intestinal inflammation Microbial intervention strategy

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Genome-wide identification,expression and functional analysis of sugar transporters in sorghum(Sorghum bicolor L.)

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Journal of Integrative Agriculture 2022年第10期21卷 2848-2864页

作者： xiao Qian-lin LI zhen WANG Ya-yun HOU xian-bin WEI Xi-mei ZHAO xiao HUANG Lei GUO Yan-jun LIU Zhi-zhai College of Agronomy and Biotechnology Southwest UniversityChongqing 400715P.R.China State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural UniversityChengdu 611130P.R.China College of Agriculture and Food Engineering Baise UniversityBaise 533000P.R.China College of Animal Science and Technology Southwest UniversityChongqing 400715P.R.China

Sugar transporters are essential for osmotic process regulation,various signaling pathways and plant growth and ***,few studies are available on the function of sugar transporters in sorghum(Sorghum bicolor L.).In this study,we performed a genome-wide survey of sugar transporters in *** total,98 sorghum sugar transporters(SSTs)were identified via *** SSTs were classified into three families based on the phylogenetic and conserved domain analysis,including six sucrose transporters(SUTs),23 sugars will eventually be exported transporters(SWEETs),and 69 monosaccharide transporters(MSTs).The sorghum MSTs were further divided into seven subfamilies,including 24 STPs,23 PLTs,two VGTs,four INTs,three p Glc T/SBG1 s,five TMTs,and eight *** localization of the SST genes showed that they were randomly distributed on 10 chromosomes,and substantial clustering was evident on the specific ***-seven SST genes from the families of SWEET,ERD,STP,and PLT were found to cluster in eight tandem repeat event *** total,22 SSTs comprising 11 paralogous pairs and accounting for 22.4%of all the genes were located on the duplicated *** different subfamilies of SST proteins possessed the same conserved domain,but there were some differences in features of the motif and transmembrane helices(TMH).The publicly-accessible RNA-sequencing data and real-time PCR revealed that the SST genes exhibited distinctive tissue specific *** studies showed that seven SSTs were mainly located on the cell membrane and membrane organelles,and 14 of the SSTs could transport different types of monosaccharides in *** findings will help us to further elucidate their roles in the sorghum sugar transport and sugar signaling pathways.

关键词： sorghum(Sorghum bicolor L.) sugar transporter SUT SWEET MST phylogenetic analysis

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A Study on Performance and Reliability of Urethral Valve Driven by Ultrasonic-vaporized Steam

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International Journal of Automation and computing 2020年第5期17卷 752-762页

作者： zhen Hu xiao Li Ting Guan School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510006China

The aim of this study is to investigate the performance and reliability of urethral valve driven by ultrasonic-vaporized *** performance model of urethral valve is established to analyze the driving and opening/closing performances of urethral *** reliability model of urethral valve is obtained,and the reliability simulation algorithm is proposed to calculate the reliability index of urethral *** numerical simulation and experimental results show that urethral valve has a good opening/closing performance,the driving performance can be improved by increasing ultrasonic intensity,radiation area and ultrasonic frequency,and the corrosion and aging of driving bags are the weak links of urethral valve.

关键词： Urethral valve ultrasonic opening/closing performance driving performance reliability

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