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A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： Wei WEI Feng GUAN xin fang College of Intelligent Science National University of Defense Technology Naval Research Academy

A metamaterial vibration isolator, termed as wave-insulating isolator, is proposed, which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave insulation. It consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and narrow. The bandgap mechanisms, vibration isolation properties, effects of key parameters, and robustness to complex conditions are clarified. As experimentally demonstrated, the wave-insulating isolator can improve the vibration insulation in the ranges of [50 Hz, 180 Hz] and [260 Hz,400 Hz] by 15 dB and 25 dB, respectively, in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate O328 34A30 74K20

Cascaded four-wave mixing all-optical wavelength converter based on highly nonlinear fiber deposited graphene oxide

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Journal of Materials Science & Technology 2024年第4期171卷 10-15页

作者： Yuanhongliu Gao Xiaoyu Chen Tonglei Cheng fang Wang xin Yan College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China

The all-optical wavelength conversion using cascaded four-wave mixing(FWM)phenomena with graphene oxide(GO)and a highly nonlinear fiber(HNLF)device is demonstrated experimentally.GO has a strong third-order nonlinear effect and is an excellent nonlinear optical material for nonlinear optical wavelength conversion.The group velocity matching of pump and signal,HNLF,and GO amplification promote the cascaded nonlinear frequency mixing process.From the experimental and analytical results,the maximum spacing between signal and pump is 21 nm,and specifically,the order of cascaded FWM light increases from order 1 to order 2 with increasing GO,and the first-order FWM conversion effi-ciency increases to a maximum of−14.5 dB.To the best of our knowledge,this is the first time that cascaded FWM-based all-optical wavelength conversion in HNLF-GO with wide wavelength selectivity is investigated with combined pump and signal light.Our findings not only provide an effective method for achieving all-optical wavelength conversion in cascaded FWM but also offer the possibility of fabricating high-performance nonlinear optical devices.

关键词： Four-wave mixing Graphene oxide Highly nonlinear fiber Optical wavelength conversion

Association between serum estradiol level and appendicular lean mass index in middle-aged postmenopausal women

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World Journal of Orthopedics 2024年第1期15卷 45-51页

作者： fang Jin Yan-Fei Wang Zhong-xin Zhu Department of Osteoporosis Care and Control Xiaoshan Affiliated Hospital of Wenzhou Medical UniversityHangzhou 311200Zhejiang ProvinceChina

BACKGROUND Previous studies investigating the association between loss of estrogen at menopause and skeletal muscle mass came to contradictory conclusions.AIM To evaluate the association between serum estradiol level and appendicular lean mass index in middle-aged postmenopausal women using population-based data.METHODS This study included 673 postmenopausal women,aged 40-59 years,from the National Health and Nutrition Examination Survey between 2013 and 2016.Weighted multivariable linear regression models were used to evaluate the association between serum E2 Level and appendicular lean mass index(ALMI).When non-linear associations were found by using weighted generalized additive model and smooth curve fitting,two-piecewise linear regression models were further applied to examine the threshold effects.RESULTS There was a positive association between serum E2 level and ALMI.Compared to individuals in quartile 1 group,those in other quartiles had higher ALMI levels.An inverted U-shaped curve relationship between serum E2 Level and ALMI was found on performing weighted generalized additive model and smooth curve fitting,and the inflection point was identified as a serum E2 level of 85 pg/mL.CONCLUSION Our results demonstrated an inverted U-shaped curve relationship between serum E2 levels and ALMI in middle-aged postmenopausal women,suggesting that low serum E2 levels play an important in the loss of muscle mass in middleaged postmenopausal women.

关键词： Estradiol Skeletal muscle Menopause Health The National Health and Nutrition Examination Survey

Regulation of AMPK activation by extracellular matrix stiffness in pancreatic cancer

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Genes & Diseases 2024年第3期11卷 338-350页

作者： xin Xu Yuan fang Somaira Nowsheen Ye-Xiong Li Zhenkun Lou Min Deng State Key Laboratory of Molecular Oncology and Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of General Surgery Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China Department of General Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Department of Dermatology University of California San DiegoSan DiegoCA 92093USA Department of Oncology Mayo ClinicRochesterMN 55905USA

The adenosine monophosphate(AMP)-activated protein kinase(AMPK)sits at a cen-tral node in the regulation of energy metabolism and tumor progression.AMPK is best known to sense high cellular ADP or AMP levels,which indicate the depletion of energy stores.Previous studies have shown that the low expression of phosphorylated AMPK is associated with a poor prognosis of pancreatic cancer.In this study,we report that AMPK is also highly sensitive to extracellular matrix(ECM)stiffness.We found that AMPK is activated in cells when cultured under low ECM stiffness conditions and is functionally required for the metabolic switch induced by ECM stiffness.This regulation of AMPK requires the Hippo kinases but not LKB1/CaMKKp.Hippo kinases directly phosphorylate AMPKa at Thr172 to activate AMPK at low ECM stiffness.Furthermore,we found AMPK activity is inhibited in patients with pancreatic ductal adenocarcinoma(PDAC)with high ECM stiffness and is associated with a poor survival outcome.The activation of Hippo kinases by ROCK inhibitor Y-27632 in combination with the mitochondrial inhibitor metformin synergistically activates AMPK and dramatically inhibits PDAC growth.Together,these findings establish a novel model for AMPK regulation by the mechanical properties of ECMs and provide a rationale for simultaneously targeting the ECM stiffness-Hippo kinases-AMPK signaling and low glucose-LKB1-AMPK signaling pathways as an effective therapeutic strategy against PDAC.

关键词： AMPKactivity Cellularmetabolic switch ECM stiffness Hippokinase signaling Pancreaticductal adenocarcinoma

Synchronous deprotonation–protonation for mechanically robust chitin/aramid nanofibers conductive aerogel with excellent pressure sensing, thermal management, and electromagnetic interference shielding

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Nano Research 2024年第3期17卷 2038-2049页

作者： xinxin Zhang Kunpeng Qian Jianhui fang Sineenat Thaiboonrod Miao Miao xin Feng Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Research Center of Nano Science and Technology College of SciencesShanghai UniversityShanghai 200444China School of Materials Sciences and Engineering Shanghai UniversityShanghai 200444China National Nanotechnology Center(NANOTEC) National Science and Technology Development Agency(NSTDA)Thailand Science ParkPathum Thani 12120Thailand

Aerogels with regularly porous structure and uniformly distributed conductive networks have received extensive attention in wearable electronic sensors,electromagnetic shielding,and so on.However,the poor mechanical properties of the emerging nanofibers-based aerogels are limited in practical applications.In this work,we developed a synchronous deprotonation–protonation method in the KOH/dimethyl sulfoxide(DMSO)system at room temperature for achieving chitin cross-linked aramid nanofibers(CANFs)rather than chitin nanofibers(ChNFs)and aramid nanofibers(ANFs)separately by using chitin and aramid pulp as raw materials.After freeze-drying process,the cross-linked chitin/aramid nanofibers(CA)aerogel exhibited the synergetic properties of ChNF and ANF by the dual-nanofiber compensation strategy.The mechanical stress of CA aerogel was 170 kPa at 80%compressive strain,increased by 750%compared with pure ChNF aerogel.Similarly,the compressibility of CA aerogel was somewhat improved compared to ANF aerogel.The enhancement verified that the crosslinking reaction between ANF and ChNF during the synchronous deprotonation process was formed.Afterwards,the conductive aerogels with uniform porous structure(CA-M)were successfully obtained by vacuum impregnating CA aerogels in Ti_(3)C_(2)T_(x) MXene solution,displaying low thermal conductivity(0.01 W/(m·K)),high electromagnetic interference(EMI)shielding effectiveness(SE)(75 dB),flame retardant,and heat insulation.Meanwhile,the as-obtained CA-M aerogels were also applied as a pressure sensor with excellent compression cycle stability and superior human motion monitoring capabilities.As a result,the dual-nanofiber based conductive aerogels have great potentials in flexible/wearable electronics,EMI shielding,flame retardant,and heat insulation.

关键词： synchronous deprotonation–protonation electromagnetic interference(EMI)shielding flame retardant heat insulation pressure sensing

Research on Hepatocyte Regulation of PCSK9-LDLR and Its Related Drug Targets

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Chinese Journal of Integrative Medicine 2024年第7期30卷 664-672页

作者： LIU Su-su YU Tong QIAO Yan-fang GU Shu-xiao CHAI xin-lou School of Traditional Chinese Medicine Beijing University of Chinese Medicine

The prevalence of hyperlipidemia has increased significantly due to genetic, dietary, nutritional and pharmacological factors, and has become one of the most common pathological conditions in humans. Hyperlipidemia can lead to a range of diseases such as atherosclerosis, stroke, coronary heart disease, myocardial infarction, diabetes, and kidney failure, etc. High circulating low-density lipoprotein cholesterol(LDL-C) is one of the causes of hyperlipidemia. LDL-C in the blood binds to LDL receptor(LDLR) and regulates cholesterol homeostasis through endocytosis. In contrast, proprotein convertase subtilisin/kexin type 9(PCSK9) mediates LDLR degradation via the intracellular and extracellular pathways, leading to hyperlipidemia. Targeting PCSK9-synthesizing transcription factors and downstream molecules are important for development of new lipid-lowering drugs. Clinical trials regarding PCSK9 inhibitors have demonstrated a reduction in atherosclerotic cardiovascular disease events. The purpose of this review was to explore the target and mechanism of intracellular and extracellular pathways in degradation of LDLR and related drugs by PCSK9 in order to open up a new pathway for the development of new lipid-lowering drugs.

关键词： hyperlipidemia proprotein convertase subtilisin/kexin type 9 low-density lipoprotein receptor intracellular pathway extracellular pathway

Activity regulation and applications of metal-organic framework-based nanozymes

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Rare Metals 2024年第3期43卷 900-914页

作者： Ge fang Shou-xin Bao Gen-Xiu Zhou Cui-Cui Ge State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSchool for Radiological and Interdisciplinary Sciences(RAD-X)Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123China Suzhou Nanomicro Technology Co. LtdSuzhou 215000China

As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental fields.Among the various reported nanozymes,metal-organic frameworks(MOFs)could mimic the active center of natural enzymes and provide a hydrophobic environment,which makes MOFs attractive alternatives to natural enzymes.Owing to the highly structural diversity and tailorability of MOFs,rational design will contribute to improve the activity of MOF-based nanozymes and promote their potential applications in both biomedical and environmental fields.Therefore,a comprehensiye suminary of activity regulatory strategies of MOF-based nanozymes is urgently needed.Firstly,we summarized the activity regulatory strategies of MOFs with intrinsic enzyme-like activities via modulation of metal nodes,ligands,structures and morphologies.Then the applications of MOF-based nanozymes in biosensing,hazardous degradation,antibacterial,and cancer therapy were also introduced.Finally,the current challenges and future perspectives were discussed in depth.It is highly expected that this review will provide a better understanding on the rational design of novel high-performance MOF-based nanozymes.

关键词： Metal-organic frameworks(MOF)-based nanozymes Activity regulation Biosensing Cancer therapy Hazardous degradation Antibacterial

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Interpretation of the Standards of Basic Dataset of Chronic Diseases Behavior Risk Factor Surveillance in Adults

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Biomedical and Environmental Sciences 2024年第5期37卷 551-556页

作者： ZHAO Yan fang ZHANG Mei WEI Wen Qiang SUN Ke xin LI xin Hua WANG Li Min National Center for Chronic and Noncommunicable Disease Control and Prevention(NCNCD) Chinese Center for Disease Control and PreventionBeijing 100050China Cancer Hospital Chinese Academy of Medical SciencesBeijing 100021China Chinese Center for Disease Control and Prevention Beijing 102206China People's Medical Publishing House Beijing 100021China

BACKGROUND China’s Behavioral Risk Factor Surveillance System(BRFSS)originated from the World Bankfunded HealthⅦLoan Project in the 1990s,which conducted behavioral risk factor surveillance in seven cities and one province^([1]).Drawing on the World Health Organization’s(WHO)STEPwise approach to surveillance(STEPs)and the U.S.Behavioral Risk Factor Surveillance System(BRFSS)^([2,3]).

关键词： funded Basic originated

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Fecal microbiota transplantation:whole grain highland barley improves glucose metabolism by changing gut microbiota

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Food Science and Human Wellness 2024年第4期13卷 2014-2024页

作者： xin Ren Fulong Zhang Min Zhang Yuan fang Zenglong Chen Meili Huan Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Engineering and Technology Research Center of Food AdditivesNational Grain Industry Highland Barley Deep Processing Technology Innovation CenterBeijing Technology and Business UniversityBeijing 100048China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China COFCO Nutrition and Health Research Institute Beijing 102209China

Highland barley(HB)is a high-altitude cereal with rich nutritional components and potential health benefits.To clarify its hypoglycemic effect and mechanism,we investigated the effect of whole grain HB and fecal microbiota transplantation(FMT)on glucose metabolism and gut microbiota in high-fat diet and streptozotocin(HFD/STZ)-induced diabetic mice.The results showed that HB(40%)significantly decreased fasting blood glucose and the area under the glucose tolerance curve,significantly increased insulin secretion and improved insulin resistance in HFD/STZ-induced diabetic mice(P<0.05).Inflammatory factors and blood lipid indices were also significantly alleviated after 12 weeks of 40%HB intervention(P<0.05).Additionally,beneficial bacteria,such as Bifidobacterium and Akkermansia,were significantly enriched in the gut of diabetic mice after whole grain HB intervention.Meanwhile,the results of further FMT experiments verified that the fecal microbiota after the 40%HB intervention not only significantly increased the relative abundance of Bifidobacterium and Akkermansia but also effectively improved glucose metabolism and alleviated the inflammatory state in HFD/STZ-induced diabetic mice.Collectively,our study confirmed the bridge role of gut microbiota in improving glucose metabolism of whole grain HB,which could promote the development of precision nutrition.

关键词： Highland barley Diabetes Glucose metabolism Gut microbiota Fecal bacteria transplantation

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