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Impact of Carbon Chain Structures in the Backbone on the Flexibility of Modified Polyarylene Sulfide Resins: Molecular Dynamics Simulations and Mesoscopic Analysis

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Chinese Journal of Polymer Science 2024年第4期42卷 544-557页

作者： Chi Zhang Rong liu jing-Yuan liu Wen-Wei Jiang Key Laboratory of Fine Chemical Engineering and Functional Materials School of Chemical EngineeringSichuan UniversityChengdu610065China

In the domain of high-performance engineering polymers, the enhancement of mechanical flexibility in poly(phenylene sulfide) (PPS) resins has long posed a significant challenge. A novel molecular structure, designated as PP-He-IS, wherein imide rings and an aliphatic hexylene chain are covalently incorporated into the PPS backbone to enhance its flexibility, is introduced in this study. Molecular dynamics (MD) simulations are employed to systematically explore the effects of diversifying the backbone chain structures by substituting phenyl units with alkyl chains of varying lengths, referred to as PP-A-IS where “A” signifies the distinct intermediary alkyl chain configurations. Computational analyses reveal a discernable decrement in the glass transition temperature (Tg) and elastic modulus, counterbalanced by an increment in yield strength as the alkyl chain length is extended. Notably, the PP-He-IS variant is shown to exhibit superior yield strength while simultaneously maintaining reduced elastic modulus and Tg values, positioning it as an advantageous candidate for flexible PPS applications. Mesoscopic analyses further indicate that structures such as PP-He-IS, PP-Pe-IS, and PP-Bu-IS manifest remarkable flexibility, attributable to the presence of freely rotatable carbon-carbon single bonds. Experimental validation confirms that a melting temperature of 504 K which is lower than that of conventional PPS, and lower crystallinity are exhibited by PP-He-IS, thereby affording enhanced processability without compromising inherent thermal stability. Novel insights into the strategic modification of PPS for mechanical flexibility are thus furnished by this study, which also accentuates the pivotal role played by molecular dynamics simulations in spearheading high-throughput investigations in polymer material modifications.

关键词： Molecular dynamics simulations Polyarylene Sulfide Main-chain modifications Flexibility Aliphatic hexylene chain

Upper extremity motor function before and after the cerebrospinal fluid tap test in patients with idiopathic normal pressure hydrocephalus: A retrospective study

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中华医学杂志(英文版) 2024年第7期137卷 877-879页

作者： liu Caiyan Wei Junji Dong Liling Mao Chenhui Li Jie Huang Xinying Hou Bo Feng Feng Cui Liying gao jing Department of Neurology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China Department of Neurosurgery Department of Neurosurgery and Radiology

Liquid metal biomaterials: translational medicines,challenges and perspectives

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National Science Review 2024年第2期11卷 264-284页

作者： Hanchi Xu Jincheng Lu Yikuang Xi Xuelin Wang jing liu Department of Biomedical Engineering School of Medicine Tsinghua University Beijing Tsinghua Changgung Hospital School of Clinical Medicine Tsinghua University Shanghai World Foreign Language Academy Beijing Advanced Innovation Center for Biomedical Engineering School of Engineering MedicineBeihang University Beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Until now, significant healthcare challenges and growing urgent clinical requirements remain incompletely addressed by presently available biomedical materials. This is due to their inadequate mechanical compatibility, suboptimal physical and chemical properties, susceptibility to immune rejection, and concerns about long-term biological safety. As an alternative, liquid metal(LM) opens up a promising class of biomaterials with unique advantages like biocompatibility, flexibility, excellent electrical conductivity,and ease of functionalization. However, despite the unique advantages and successful explorations of LM in biomedical fields, widespread clinical translations and applications of LM-based medical products remain limited. This article summarizes the current status and future prospects of LM biomaterials, interprets their applications in healthcare, medical imaging, bone repair, nerve interface, and tumor therapy, etc.Opportunities to translate LM materials into medicine and obstacles encountered in practices are discussed.Following that, we outline a blueprint for LM clinics, emphasizing their potential in making new-generation artificial organs. Last, the core challenges of LM biomaterials in clinical translation, including bio-safety,material stability, and ethical concerns are also discussed. Overall, the current progress, translational medicine bottlenecks, and perspectives of LM biomaterials signify their immense potential to drive future medical breakthroughs and thus open up novel avenues for upcoming clinical practices.

关键词： liquid metal biomaterials translational medicine clinical device healthcare therapeutics

Machine learning-based predictions of current and future susceptibility to retrogressive thaw slumps across the Northern Hemisphere

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Advances in Climate Change Research 2024年第2期15卷 253-264页

作者： jing LUO Guo-An YIN Fu-Jun NIU Tian-Chun DONG Ze-Yong gao Ming-Hao liu Fan YU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. LtdXining 810000China University of Chinese Academy of Sciences Beijing 100049China

Retrogressive thaw slumps(RTSs)caused by the thawing of ground ice on permafrost slopes have dramatically increased and become a common permafrost hazard across the Northern Hemisphere during previous decades.However,a gap remains in our comprehensive understanding of the spatial controlling factors,including the climate and terrain,that are conducive to these RTSs at a global scale.Using machine learning methodologies,we mapped the current and future RTSs susceptibility distributions by incorporating a range of environmental factors and RTSs inventories.We identified freezing-degree days and maximum summer rainfall as the primary environmental factors affecting RTSs susceptibility.The final ensemble susceptibility map suggests that regions with high to very high susceptibility could constitute(11.6±0.78)%of the Northern Hemisphere's permafrost region.When juxtaposed with the current(2000-2020)RTSs susceptibility map,the total area with high to very high susceptibility could witness an increase ranging from(31.7±0.65)%(SSP585)to(51.9±0.73)%(SSP126)by the 2041-2060.The insights gleaned from this study not only offer valuable implications for engineering applications across the Northern Hemisphere,but also provide a long-term insight into the potential change of RTSs in permafrost regions in response to climate change.

关键词： Retrogressive thaw slump Machine learning Susceptibility map Permafrost Northern Hemisphere

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

Exploration of cardiac rehabilitation nursing for elderly patients with myocardial infarction based on individualized cardiac rehabilitation

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World Journal of Clinical Cases 2024年第2期12卷 256-266页

作者： Hua-Ning liu Bo gao Department of Geriatrics General Hospital of the YangTze River ShippingWuhan Brain HospitalWuhan 430015Hubei ProvinceChina Department of Cardiology Suizhou Central HospitalAffiliated Hospital of Hubei University of MedicineSuizhou 441300Hubei ProvinceChina

BACKGROUND Myocardial infarction is a high-risk condition prevalent among the elderly population,often leading to adverse clinical manifestations such as reduced cardiopulmonary function,anxiety,and depression post-surgery.Consequently,cardiac rehabilitation holds immense importance in mitigating these complications.AIM To evaluate the effect of individualized cardiac rehabilitation on blood pressure variability(BPV)and baroreflex sensitivity(BRS)in elderly patients with myocardial infarction.METHODS A cohort of 74 elderly patients diagnosed with myocardial infarction and admitted to our hospital between January 2021 and January 2022 were subjected to random selection.Subsequently,all patients were divided into two groups,namely the research group(n=37)and the control group(n=37),utilizing the number table method.The control group received conventional drug treatment and nursing guidance intervention,while the study group underwent individualized cardiac rehabilitation in addition to the interventions received by the control group.All patients were continuously intervened for 12 wk,and the BPV of these two groups in the 1st wk(T0),the 4th wk(T1)and the 12th wk(T2)were compared,BRS,changes in cardiopulmonary function measures,and adverse cardiovascular events.RESULTS Of 24 h diastolic BPV,24 h systolic BPV,carbon dioxide ventilation equivalent slope of the research group were lower than those of the control group at T1 and T2,BRS,peak heart rate and systolic blood pressure product,1 min heart rate recovery were higher than those of the control group,and the incidence of adverse events in the research group was lower than that of the control group,the difference was statistically significant(P<0.05).CONCLUSION In this study,we found that after individualized cardiac rehabilitation in elderly patients with myocardial infarction,BPV and BRS can be effectively improved,cardiac function is significantly enhanced,and a better prognosis is obtained.

关键词： Individualized cardiac rehabilitation Myocardial infarction Variability in blood pressure Baroreflex sensitivity

Effect of Blood Circulation in Veins on Resonance Suppression of the Dragonfly Wing Constructed by Numerical Method

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Journal of Bionic Engineering 2024年第2期21卷 877-891页

作者： Lijun Zhang Xu Zhang Kaifei Wang Zhenwei Gan Shibo liu Xiao liu Zhengjun jing Xudong Cui Jiahui Lu jing liu College of Mechanical and Electronic Engineering China University of PetroleumQingdao266580China

To reveal the resonance suppression mechanism of the blood circulation in dragonfly wings,a numerical modeling method of dragonfly wings based on Voronoi diagrams is proposed,and the changes in mass,aerodynamic damping,and natural frequencies caused by blood circulation in veins are investigated.The equivalent mass of blood,boundary conditions,and aerodynamic damping are calculated theoretically.Modal analysis and harmonic response analysis of wing models with different blood circulation paths are performed using the finite-element method(FEM).The vibration reduction ratioδis introduced to compare the damping efficiency of different mass regions.Finally,a natural frequency testing device is constructed to measure the natural frequencies of dragonfly wings.The results indicate that the shape,mass,and natural frequencies of the dragonfly wing model constructed by numerical method agree well with reality.The mass distribution on the wing can be altered by blood circulation,thereby adjusting the natural frequencies and achieving resonance suppression.The highestδof 1.013 is observed in the C region when blood circulates solely in secondary veins,but it is still lower than theδof 1.017 when blood circulates in complete veins.The aerodynamic damping ratio(1.19–1.79%)should not be neglected in the vibration analysis of the beating wing.

关键词： Dragonfly wings Blood circulation Resonance suppression Voronoi diagram FEM

Elevated Kallistatin promotes the occurrence and progression of non-alcoholic fatty liver disease

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1730-1744页

作者： Zhenzhen Fang Gang Shen Yina Wang Fuyan Hong Xiumei Tang Yongcheng Zeng Ting Zhang Huanyi liu Yanmei Li Jinhong Wang jing Zhang Anton gao Weiwei Qi Xia Yang Ti Zhou Guoquan gao Department of Biochemistry Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhou 510080China Department of VIP Medical Center the Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510080China Physical Examination Center the Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510080China Department of Clinical Laboratory Guangzhou First People's HospitalGuangzhou 510080China Guangdong Key Laboratory of Liver Disease Research the Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 51008China Department of Health Sciences College of Health SolutionsArizona State UniversityTempeUSA Guangdong Engineering&Technology Research Center for Gene Manipulation and Biomacromolecular Products Sun Yat-Sen UniversityGuangzhou 510080China Guangdong Province Key Laboratory of Diabetology Guangzhou 510o80China Guangdong Province Key Laboratory of Brain Function and Disease Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhou 510080China

Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease worldwide,and the development of nonalcoholic steatohepatitis(NASH)might cause irreversible hepatic damage.Hyperlipidemia(HLP)is the leading risk factor for NAFLD.This study aims to illuminate the causative contributor and potential mechanism of Kallistatin(KAL)mediating HLP to NAFLD.221 healthy control and 253 HLP subjects,62 healthy control and 44 NAFLD subjects were enrolled.The plasma KAL was significantly elevated in HLP subjects,especially in hypertriglyceridemia(HTG)subjects,and positively correlated with liver injury.Further,KAL levels of NAFLD patients were significantly up-regulated.KAL transgenic mice induced hepatic steatosis,inflammation,and fibrosis with time and accelerated inflammation development in high-fat diet(HFD)mice.In contrast,KAL knockout ameliorated steatosis and inflammation in high-fructose diet(HFruD)and methionine and choline-deficient(MCD)diet-induced NAFLD rats.Mechanistically,KAL induced hepatic steatosis and NASH by down-regulating adipose triglyceride lipase(ATGL)and comparative gene identification 58(CGl-58)by LRP6/Gas/PKA/GSK3βpathway through down-regulating peroxisome proliferator-activated receptor(PPARy)and up-regulating kruppel-like factor four(KLF4),respectively.CGl-58 is bound to NF-kB p65 in the cytoplasm,and diminishing CGl-58 facilitated p65 nuclear translocation and TNFa induction.Meanwhile,hepatic CGl-58-overexpress reverses NASH in KAL transgenic mice.Further,free fatty acids up-regulated KAL against thyroid hormone in hepatocytes.Moreover,Fenofibrate,one triglyceride-lowering drug,could reverse hepatic steatosis by down-regulating KAL.These results demonstrate that elevated KAL plays a crucial role in the development of HLP to NAFLD and may be served as a potential preventive and therapeutic target.

关键词： GSK3β inflammation elevated

Skin neuropathy and immunomodulation in diseases

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Fundamental Research 2024年第2期4卷 218-225页

作者： Manze Zhang Tingting liu jing Yang Department of Biology Stanford UniversityStanfordCA 94305USA Department of Biochemistry Weill Cornell Medical CollegeNew YorkNY 10065USA IDG/McGovern Institute for Brain Research Center for Life SciencesSchool of Life SciencesPeking UniversityBeijing 100871China Peking University Third Hospital Cancer Center Beijing 100191China

Skin is a vital barrier tissue of the body.Immune responses in the skin must be precisely controlled,which would otherwise cause severe disease conditions such as psoriasis,atopic dermatitis,or pathogenic infection.Research evidence has increasingly demonstrated the essential roles of neural innervations,i.e.,sensory and sympathetic signals,in modulating skin immunity.Notably,neuropathic changes of such neural structures have been observed in skin disease conditions,implicating their direct involvement in various pathological processes.An in-depth understanding of the mechanism underlying skin neuropathy and its immunomodulatory effects could help reveal novel entry points for therapeutic interventions.Here,we summarize the neuroimmune interactions between neuropathic events and skin immunity,highlighting the current knowledge and future perspectives of this emerging research frontier.

关键词： Skin Neuropathy Neuroimmune Psoriasis Atopic dermatitis Pathogenic infection