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Unlocking the Potential of Poly(butylene succinate) through Incorporation of Vitrimeric Network Based on Dynamic Imine Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1414-1424页

作者： Shan-Song Wu Hui-Juan Lu Yi-Dong Li shui-Dong Zhang Jian-bing Zeng Chongqing Key Laboratory of Soft-Matter Material Manufacturing School of Chemistry and Chemical Engineering Southwest University School of Mechanical and Automotive Engineering South China University of Technology

Poly(butylene succinate)(PBS) exhibits many advantages, such as renewability, biodegradability, and impressive thermal and mechanical properties, but is limited by the low melt viscosity and strength resulted from the linear structure. To address this, vitrimeric network was introduced to synthesize PBS vitrimers(PBSVs) based on dynamic imine bonds through melt polymerization of hydroxyl-terminated PBS with vanillin derived imine containing compound and hexamethylene diisocyanate using trimethylolpropane as a crosslinking monomer. PBSVs with different crosslinking degrees were synthesized through changing the content of the crosslinking monomer. The effect of crosslinking degree on the thermal, theological, mechanical properties, and stress relaxation behavior of the PBSVs was studied in detail. The results demonstrated that the melt viscosity, melt strength, and heat resistance were enhanced substantially without obvious depression in crystallizability, thermal stability, and mechanical properties through increasing crosslinking degree. In addition, the PBSVs exhibit thermal reprocessability with mechanical properties recovered by more than 90% even after processing for three times. Furthermore, PBSV with improved melt properties shows significantly improved foamability compared to commercial PBS. This research contributes to the advancement of polymer technology by successfully developing PBS vitrimers with improved properties, showcasing their potential applications in sustainable and biodegradable materials.

关键词： Foamability Imine bonds Poly(butylene succinate) Vitrimer

Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons

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Biomedical and Environmental Sciences 2024年第5期37卷 479-493页

作者： LI Yang LIN Dan ZHANG xiu Qin JU Guang xiu SU Ya ZHANG Qian DUAN Hai Ping YU Wei Sen WANG bing Ling PANG Shu Tao Department of Epidemiology and Health Statistics School of Public HealthQingdao UniversityQingdao 266021ShandongChina Department of Environmental Health Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Physicochemical Laboratory Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Section of Child Health Care Huangdao Maternity and Child Health Care Hospital of QingdaoQingdao 266499ShandongChina Qingdao Blood Center Qingdao 266071ShandongChina

Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal *** Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old ***,37 children were categorized into low-and high-exposure groups based on the sum of the ten ***-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine ***,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina *** The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide ***,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in *** Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived *** investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes.

关键词： Child Gut microbiota Non-targeted metabolomics Polycyclic aromatic hydrocarbons Urinary metabolite profile

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Refining the targeted population and achieving better for colorectal cancer screening

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World Journal of Gastroenterology 2024年第25期30卷 3140-3142页

作者： Nuo-Ya Zhou Yi-xiu Lin Liu-Xiang Chen Lian-Song Ye bing Hu Department of Gastroenterology and Hepatology/Medical Engineering Integration Laboratory of Digestive Endoscopy West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

This editorial comments on the article entitled“Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened?”by Agatsuma et al,who conducted a retrospective study aiming at clarifying the stage at colorectal cancer(CRC)diagnosis based on different diagnostic *** share our opinion about CRC screening *** current situation suggests the need for a more specific and targeted population for CRC screening.

关键词： Colorectal cancer Screening Early diagnosis Technology Cost-effectiveness

Construction and performance test of charged particle detector array for MATE

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Nuclear Science and Techniques 2024年第8期35卷 92-100页

作者： Xiao‑Bin Li Long‑Hui Ru Zhi‑Chao Zhang bing‑Feng Lv Ning‑Tao Zhang Jin‑Long Zhang Chen‑Gui Lu bing‑shui Gao Jun‑bing Ma Fu‑Shuai Shi Satoru Terashima Xiao‑Dong Xu Zhen Bai Shi‑Wei Xu Yan‑Yun Yang Hooi‑Jin Ong Xiao‑Dong Tang Institute of Modern Physics(IMP) Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Research Center for Nuclear Physics Osaka UniversityIbarakiOsaka 567‑0047Japan RIKEN Nishina Center WakoSaitama 351‑0198Japan Joint Department for Nuclear Physics Lanzhou University and Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China

A charged particle array named MATE-PA,which serves as an auxiliary detector system for a Multi-purpose Active-target Time projection chamber used in nuclear astrophysical and exotic beam Experiments(MATE),was *** array comprised of 20 single-sided strip-silicon detectors covering approximately 10%of the solid *** detectors facilitated the detection of reaction-induced charged particles that penetrate the active volume of the *** performance of MATE-PA has been experimentally studied using an alpha source and a 36-MeV 14 N beam injected into the MATE chamber on the radioactive ion beam line in Lanzhou(RIBLL).The chamber was filled with a gas mixture of 95%4 He and 5%CO_(2) at a pressure of 500 *** results indicated good separation of light-charged particles using the forward double-layer silicon detectors of *** energy resolution of the Si detectors was deduced to be approximately 1%(σ)for an energy loss of approximately 10 MeV caused by theα*** inclusion of MATE-PA improves particle identification and increases the dynamic range of the kinetic energy of charged particles,particularly that of theαparticles,up to approximately 15 MeV.

关键词： Silicon detector array Active target Time projection chamber

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Atomic-Scale Insights into Damage Mechanisms of GGr15 Bearing Steel Under Cyclic Shear Fatigue

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1265-1278页

作者： Qiao-Sheng Xia Dong-Peng Hua Qing Zhou Ye-Ran Shi Xiang-Tao Deng Kai-Ju Lu Hai-Feng Wang xiu-bing Liang Zhao-Dong Wang State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an710072China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Alternating shear stress is a critical factor in the accumulation of damage during rolling contact fatigue,severely limiting the service life of ***,the specific mechanisms responsible for the cyclic shear fatigue damage in bearing steel have not been fully *** the mechanical response and microstructural evolution of a model GGr15 bearing steel under cyclic shear loading are investigated through the implementation of molecular dynamics *** samples undergo 30 cycles under three different loading conditions with strains of 6.2%,9.2%,and 12.2%,*** findings indicate that severe cyclic shear deformation results in early cyclic softening and significant accumulation of plastic damage in the bearing ***,samples subjected to higher strain-controlled loading exhibit higher plastic strain energy and shorter fatigue ***,strain localization is identified as the predominant damage mechanism in cyclic shear fatigue of the bearing steel,which accumulates and ultimately results in fatigue ***,simulation results also revealed the microstructural reasons for the strain localization(e.g.,BCC phase transformation into FCC and HCP phase),which well explained the formation of white etching *** study provides fresh atomic-scale insights into the mechanisms of cyclic shear fatigue damage in bearing steels.

关键词： Cyclic shear fatigue Molecular dynamic simulation Bearing steels Plastic damage accumulation

Cross-reactivity of hypervariable region 1 chimera of hepatitis C virus

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World Journal of Gastroenterology 2003年第6期9卷 1256-1260页

作者： bing-shui xiu Shi-Gan Ling Xiao-Guo Song He-Qiu Zhang Kun Chen Cui-Xia Zhu Laboratory of Molecular Virology,Institute of Basic Medical Sciences,Academy of Military Medical Sciences,Beijing 100850,China Laboratory of Molecular Virology Institute of Basic Medical Sciences Academy of Military Medical Sciences Beijing 100850 P.R.China.

AIM: To analyze the amino acid sequences of hypervariable region 1 (HVR1) of HCV isolates in China and to construct a combinatorial chimeric HVR1 protein having a very broad high cross-reactivity.METHODS: All of the published HVR1 sequences from China were collected and processed with a computer *** representative HVR1's sequences were formulated based on a consensus profile and homology within certain subdivision. A few reported HVR1 mimotope sequences were also included for a broader representation. All of them were cloned and expressed in ***. The cross-reactivity of the purified recombinant HVR1 antigens was tested by ELISA with a panel of sera from HCV infected patients in *** of them were further ligated together to form a combinatorial HVR1 chimera.RESULTS: Altogether 12 HVR1s were selected and expressed in E. coli and purified to homogeneity. All of these purified antigens showed some cross-reactivity with sera in a 27 HCV positive panel. Recombinant HVR1s of No. 1, 2, 4, and 8# showing broad cross-reactivities and complementarity with each other, were selected for the ligation elements. The chimera containing these 4 HVR1s was highly expressed in E. coli. The purified chimeric antigen could react not only with all the HCV antibody positive sera in the panel but also with 90/91 sera of HCV -infected patients.CONCLUSION: The chimeric antigen was shown to have a broad cross-reactivity. It may be helpful for solving the problem caused by high variability of HCV, and in the efforts for a novel vaccine against the virus.

关键词：丙型肝炎病毒超变量区域1 基因序列分析交叉反应性嵌合体抗原

Heterogeneously elevated branched-chain/aromatic amino acids among new-onset type-2 diabetes mellitus patients are potentially skewed diabetes predictors

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World Journal of Diabetes 2024年第1期15卷 53-71页

作者： Min Wang Yang Ou Xiang-Lian Yuan xiu-Fang Zhu Ben Niu Zhuang Kang bing Zhang Anwar Ahmed Guo-Qiang Xing Heng Su School of Chemical Science and Technology Yunnan UniversityKunming 650091Yunnan ProvinceChina Department of Endocrinology The First People’s Hospital of Yunnan ProvinceKunming 650032Yunnan ProvinceChina Clinical Laboratory Nanchong Central Hospital&The Second Clinical Medical College of North Sichuan Medical UniversityNanchong 637000Sichuan ProvinceChina Department of Preventive Medicine and Biostatistics Uniformed Services University of the Health SciencesBethesdaMD 20814United States The Affiliated Hospital and Second Clinical Medical College North Sichuan Medical UniversityNanchong 637000Sichuan ProvinceChina Department of Research and Development Lotus *** LLCGaithersburgMD 20878United States

BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention *** branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amino acids(AAAs:Tyrosine,tryptophan,phenylalanine)show high sensitivity and specificity in predicting diabetes in animals and predict T2DM 10-19 years before T2DM onset in clinical ***,improvement is needed to support its clinical *** To evaluate the effects of body mass index(BMI)and sex on BCAAs/AAAs in new-onset T2DM individuals with varying body *** Ninety-seven new-onset T2DM patients(<12 mo)differing in BMI[normal weight(NW),n=33,BMI=22.23±1.60;overweight,n=42,BMI=25.9±1.07;obesity(OB),n=22,BMI=31.23±2.31]from the First People’s Hospital of Yunnan Province,Kunming,China,were ***-way and 2-way ANOVAs were conducted to determine the effects of BMI and sex on BCAAs/*** Fasting serum AAAs,BCAAs,glutamate,and alanine were greater and high-density lipoprotein(HDL)was lower(P<0.05,each)in OB-T2DM patients than in NW-T2DM patients,especially in male OB-T2DM ***,histidine,leucine,methionine,and lysine were greater in male patients than in female ***,histidine,alanine,glutamate,lysine,valine,methionine,leucine,isoleucine,tyrosine,phenylalanine,and tryptophan were significantly correlated with abdominal adiposity,body weight and BMI,whereas isoleucine,leucine and phenylalanine were negatively correlated with *** Heterogeneously elevated amino acids,especially BCAAs/AAAs,across new-onset T2DM patients in differing BMI categories revealed a potentially skewed prediction of T2DM *** higher BCAA/AAA levels in obese T2DM patients would support T2DM prediction in obese individuals,whereas the lower levels of BCAAs/AAAs in NW-T2DM individuals may underestimate T2DM risk in NW *** potentially skewed T2DM prediction should be considered when BCAAs/AAAs are to

关键词： Hyperaminoacidemia Branched-chain/aromatic amino acids New-onset type-2 diabetes Predictor Obesity Sex

Triceps skinfold thickness trajectories and the risk of all-cause mortality:A prospective cohort study

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World Journal of Clinical Cases 2024年第15期12卷 2568-2577页

作者： Na Yang Li-Yun He Zi-Yi Li Yu-Cheng Yang Fan Ping Ling-Ling Xu Wei Li Hua-bing Zhang Yu-xiu Li Department of Endocrinology Key Laboratory of Endocrinology of National Health CommissionPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

BACKGROUND The measurement of triceps skinfold(TSF)thickness serves as a noninvasive metric for evaluating subcutaneous fat *** its clinical utility,the TSF thickness trajectories and their correlation with overall mortality have not been thoroughly *** To explore TSF thickness trajectories of Chinese adults and to examine their associations with all-cause *** This study encompassed a cohort of 14747 adults sourced from the China Health and Nutrition *** class trajectory modeling was employed to identify distinct trajectories of TSF *** were classified into subgroups reflective of their respective TSF thickness *** utilized multivariate Cox regression analyses and mediation examinations to explore the link between TSF thickness trajectory and overall mortality,including contributory *** Upon adjustment for multiple confounding factors,we discerned that males in the‘Class 2:Thin-stable’and‘Class 3:Thin-moderate’TSF thickness trajectories exhibited a markedly reduced risk of mortality from all causes in comparison to the‘Class 1:Extremely thin’*** the mediation analyses,the Geriatric Nutritional Risk Index was found to be a partial intermediary in the relationship between TSF thickness trajectories and *** females,a lower TSF thickness pattern was significantly predictive of elevated all-cause mortality risk exclusively within the non-elderly *** In males and non-elderly females,lower TSF thickness trajectories are significantly predictive of heightened mortality risk,independent of single-point TSF thickness,body mass index,and waist circumference.

关键词： Triceps skinfold thickness Trajectory All-cause mortality Body mass index Geriatric Nutritional Risk Index

Generating attosecond pulses with controllable polarization from cyclic H_(3)^(2+) molecules by bichromatic circular fields

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Chinese Physics B 2024年第2期33卷 305-310页

作者：张思琪张冰闫博姜向前孙秀冬 School of Physics Harbin Institute of TechnologyHarbin 150001China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

We investigate the polarization properties of harmonics from the cyclic H_(3)^(2+) molecular ions in tailored bichromatic counter-rotating circularly polarized(BCCP)fields by solving the time-dependent Schrödinger *** allowed harmonics and their helicities are associated with the symmetry compatibility of the field-target systems,and large intensity difference between adjacent harmonics with opposite helicities appears in a wide spectral range when the BCCP field is at certain rotation *** try to explain the intensity difference by using a recombination model based on the quantum-orbit theory and by analyzing the ionization ***,to synthesize attosecond pulse trains with tunable polarization,the intensity difference is manipulated by introducing a seed XUV field,and by changing the relative amplitude ratio as well as the helicity of BCCP fields.

关键词： high-order harmonic generation attosecond pulse multi-center interference

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