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Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

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Chinese Journal of Polymer Science 2024年第2期42卷 256-266,I0010页

作者： Can-Can Zhang jun-Long yang ya-Jiang Huang Guang-Xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction

FibroScan-aspartate transaminase:A superior non-invasive model for diagnosing high-risk metabolic dysfunction-associated steatohepatitis

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World Journal of Gastroenterology 2024年第18期30卷 2440-2453页

作者： Jing-ya Yin Tian-Yuan yang Bing-Qing yang Chen-Xue Hou jun-Nan Li Yue Li Qi Wang Center of Liver Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Pathology Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Beijing institute of infectious disease Beijing 100015China Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)with hepatic histological NAFLD activity score≥4 and fibrosis stage F≥2 is regarded as“at risk”non-alcoholic steatohepatitis(NASH).Based on an international consensus,NAFLD and NASH were renamed as metabolic dysfunction-associated steatotic liver disease(MASLD)and metabolic dysfunction-associated steatohepatitis(MASH),respectively;hence,we introduced the term“high-risk MASH”.Diagnostic values of seven non-invasive models,including FibroScan-aspartate transaminase(FAST),fibrosis-4(FIB-4),aspartate transaminase to platelet ratio index(APRI),etc.for high-risk MASH have rarely been studied and compared in MASLD.AIM To assess the clinical value of seven non-invasive models as alternatives to liver biopsy for diagnosing high-risk MASH.METHODS A retrospective analysis was conducted on 309 patients diagnosed with NAFLD via liver biopsy at Beijing Ditan Hospital,between January 2012 and December 2020.After screening for MASLD and the exclusion criteria,279 patients wereincluded and categorized into high-risk and non-high-risk MASH groups.Utilizing threshold values of each model,sensitivity,specificity,positive predictive value(PPV),and negative predictive values(NPV),were calculated.Receiver operating characteristic curves were constructed to evaluate their diagnostic efficacy based on the area under the curve(AUROC).RESULTS MASLD diagnostic criteria were met by 99.4%patients with NAFLD.The MASLD population was analyzed in two cohorts:Overall population(279 patients)and the subgroup(117 patients)who underwent liver transient elastography(FibroScan).In the overall population,FIB-4 showed better diagnostic efficacy and higher PPV,with sensitivity,specificity,PPV,NPV,and AUROC of 26.9%,95.2%,73.5%,72.2%,and 0.75.APRI,Forns index,and aspartate transaminase to alanine transaminase ratio(ARR)showed moderate diagnostic efficacy,whereas S index and gamma-glutamyl transpeptidase to platelet ratio(GPR)were relatively weaker.In the subgroup,FAST had the highest diagnostic efficacy,i

关键词： Metabolic dysfunction-associated steatotic liver disease High-risk metabolic dysfunction-associated steatohepatitis Non-invasive models Liver biopsy Diagnostic value

The identification of AMZ2 as a candidate causative gene in a severe teratozoospermia patient characterized by vacuolated spermatozoa

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Asian Journal of Andrology 2024年第1期26卷 107-111页

作者： Liu Liu Jing yang Wen-Jing Zhang Yi-Ling Zhou Gui-jun Zhao ya Huang Shu-yan Tang Obstetrics and Gynecology Hospital Fudan UniversityShanghai 200011China Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases Shanghai 200011China State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development Department of Computational BiologySchool of Life SciencesFudan UniversityShanghai 200436China Shanghai Towako Hospital Shanghai 200131China Shanghai Institute of Medical Genetics Shanghai Children's HospitalShanghai Jiao Tong UniversityShanghai 200040China

Teratozoospermia with cephalic defects is one of the most severe types of sperm defects known to date.While several monogenic factors are linked to cephalic abnormalities,such as globozoospermia and macrozoospermia,the genetic cause of vacuolated spermatozoa remains inadequately described.Here,we analyzed whole-exome sequencing(WES)data for an individual from a consanguineous family with severely vacuolated spermatozoa.The analysis revealed a novel homozygous c.520A>G(p.Thr174Ala)variant in the archaelysin family metallopeptidase 2(AMZ2),a gene that encodes a zinc metalloprotease previously shown to be highly expressed in the testes and sperm.Multiple algorithms predicted this variant to be a damaging mutation.Consistent with an autosomal recessive mode of inheritance,this variant was inherited from heterozygous parental carriers.To investigate the potential pathogenicity of the identified variant,we compared the AMZ2 expression in sperm cells from the patient with the AMZ2 variant and from a healthy control.Immunoblot analysis revealed that the homozygous missense variant in AMZ2 abolished AMZ2 expression in the spermatozoa.Our findings reveal a candidate causative gene for vacuolated spermatozoa.

关键词： AMZ2 male infertility sperm quality teratozoospermia

Insights into postural orthostatic tachycardia syndrome after COVID-19 in pediatric patients

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World Journal of Pediatrics 2024年第3期20卷 201-207页

作者： ya-Xi Cui jun-Bao Du Hong-Fang Jin Department of Pediatrics Peking University First HospitalNo.1 Xi-an Men StreetWest DistrictBeijing 100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijing 100191China

The pandemic caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)profoundly threatened human health globally and greatly impacted the world economy[1].While most patients recovered,some suff... 详细信息

关键词： acute patients tachycardia

Ground state of Rydberg-dressed Bose gas confined in a toroidal trap

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Communications in Theoretical Physics 2024年第1期76卷 29-35页

作者： Lin-Xue Wang Hong-Li yang Hui Liu Si-Lin Chen ya-jun Wang Xiao-Fei Zhang Department of Physics School of Physics and Information ScienceShaanxi University of Science and TechnologyXi'an 710021China Department of Basic Sciences Air Force Engineering UniversityXi'an 710051China

The experimental realization of Rydberg dressing technology in ultracold atomic systems provides another superior platform for studying novel states of matter and macroscopic quantum phenomena.In this work,based on the mean-field theory,we have investigated the ground-state phases of a two-component Bose–Einstein condensate with Rydberg interaction and confined in a toroidal trap.The effects of the Rydberg interaction and external potential,especially the Rydberg blockade radius,on the ground-state structure of such a system have been investigated in full parameter space.Our results show that the Rydberg blockade radius,which can be regarded as another controllable parameter,can be used to obtain a variety of ground-state phases.More interestingly,it is found that for weak Rydberg interactions,the Rydberg blockade radius breaks the spontaneous rotational symmetry of the system,leading to the formation of a discrete unit cell structure.For strongly interacting cases,it can be used to realize different orders of discrete rotational symmetry breaking.

关键词： Bose-Einstein condensate Rydberg dressing toroidal trap

Highly Hydrolysis-Resistant Polyimide Fibers Prepared by Thermal Crosslinking with Inherent Carboxyl Groups

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Chinese Journal of Polymer Science 2024年第2期42卷 247-255,I0010页

Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments.

关键词： Polyimide Carboxyl group Crosslinking Hydrolysis-resistance

A mutation in TBXT causes congenital vertebral malformations in humans and mice

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Journal of Genetics and Genomics 2024年第4期51卷 433-442页

作者： Shuxia Chen Yunping Lei yajun yang Chennan Liu Lele Kuang Li Jin Richard HFinnell Xueyan yang Hongyan Wang Obstetrics and Gynecology Hospital State Key Laboratory of Genetic Engineering at School of Life SciencesKey Laboratory of Reproduction Regulation of NPFPCInstitute of Reproduction and DevelopmentFudan UniversityShanghai 200438China Shanghai Key Laboratory of Metabolic Remodeling and Health Institute of Metabolism and Integrative BiologyFudan UniversityShanghai 200438China Center for Precision Environmental Health Department of Molecular and Cellular BiologyBaylor College of MedicineHoustonTX 77030USA MOE Key Laboratory of Contemporary Anthropology School of Life SciencesFudan UniversityShanghai 200438China Department of Assisted Reproduction Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China Children’s Hospital Fudan University399 Wanyuan RoadShanghai 201102China

T-box transcription factor T(TBXT;T)is required for mesodermal formation and axial skeletal development.Although it has been extensively studied in various model organisms,human congenital vertebral malformations(CVMs)involving T are not well established.Here,we report a family with 15 CVM patients distributed across 4 generations.All affected individuals carry a heterozygous mutation,T c.596A>G(p.Q199R),which is not found in unaffected family members,indicating co-segregation of the genotype and phenotype.In vitro assays show that T p.Q199R increases the nucleocytoplasmic ratio and enhances its DNA-binding affinity,but reduces its transcriptional activity compared to the wild-type.To determine the pathogenicity of this mutation in vivo,we generated a Q199R knock-in mouse model that recapitulates the human CVM phenotype.Most heterozygous Q199R mice show subtle kinked or shortened tails,while homozygous mice exhibit tail filaments and severe vertebral deformities.Overall,we show that the Q199R mutation in T causes CVM in humans and mice,providing previously unreported evidence supporting the function of T in the genetic etiology of human CVM.

关键词： Congenital vertebral malformation TBXT T gene Loss-of-function mutation

NOX4 promotes tumor progression through the MAPK-MEK1/2-ERK1/2 axis in colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1421-1436页

作者： Yu-Jie Xu ya-Chang Huo Qi-Tai Zhao Jin-yan Liu Yi-jun Tian Lei-Lei yang Yi Zhang Biotherapy Center and Cancer Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Oncology Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityPeople’s Hospital of Henan UniversityZhengzhou 450003Henan ProvinceChina

BACKGROUND Metabolic reprogramming plays a key role in cancer progression and clinical outcomes;however,the patterns and primary regulators of metabolic reprogramming in colorectal cancer(CRC)are not well understood.AIM To explore the role of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4)in promoting progression of CRC.METHODS We evaluated the expression and function of dysregulated and survival-related metabolic genes using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes.Consensus clustering was used to cluster CRC based on dysregulated metabolic genes.A prediction model was constructed based on survival-related metabolic genes.Sphere formation,migration,invasion,proliferation,apoptosis and clone formation was used to evaluate the biological function of NOX4 in CRC.mRNA sequencing was utilized to explore the alterations of gene expression NOX4 over-expression tumor cells.In vivo subcutaneous and lung metastasis mouse tumor model was used to explore the effect of NOX4 on tumor growth.RESULTS We comprehensively analyzed 3341 metabolic genes in CRC and identified three clusters based on dysregulated metabolic genes.Among these genes,NOX4 was highly expressed in tumor tissues and correlated with worse survival.In vitro,NOX4 overexpression induced clone formation,migration,invasion,and stemness in CRC cells.Furthermore,RNA-sequencing analysis revealed that NOX4 overexpression activated the mitogen-activated protein kinase-MEK1/2-ERK1/2 signaling pathway.Trametinib,a MEK1/2 inhibitor,abolished the NOX4-mediated tumor progression.In vivo,NOX4 overexpression promoted subcutaneous tumor growth and lung metastasis,whereas trametinib treatment can reversed the metastasis.CONCLUSION Our study comprehensively analyzed metabolic gene expression and highlighted the importance of NOX4 in promoting CRC metastasis,suggesting that trametinib could be a potential therapeutic drugs of CRC clinical therapy targeting NOX4.

关键词： Colorectal cancer Metabolic reprogramming Metastasis Nicotinamide adenine dinucleotide phosphate oxidase 4 Mitogen-activated protein kinase signaling

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing Liu Xiang yang jun Liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast loading.First,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage test.Second,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation method.Finally,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact block.The calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the model.The residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged panel.The results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location