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Doping effect of Poly(vinylidene fluoride) on Carbon Nanofibers Deduced by Thermoelectric Analysis of Their Melt Mixed Films

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Chinese journal of Polymer Science 2024年第11期 1802-1810页

作者： A.j.Paleo V.M.Serrato j.M.Mánuel O.Toledano e.Mu?oz M.Melle-Franco B.Krause P.P?tschke K.Lozano 2C2T-Centre for Textile Science and Technology University of Minho Campus de Azurém Florida Institute of Technology The Aerospace Corporation Department of Condensed Matter Physics and Institute of Research on electron Microscopy and Materials(IMeYMAT) Faculty of Sciences University of Cádiz CICeCO – Aveiro Institute of Materials Department of Chemistry University of Aveiro UNeD-Universidad Nacional de educación a Distancia Facultad de Física Pontificia Universidad Católica de Chile Leibniz-Institut für Polymerforschung Dresden e.V.IPF Department of Mechanical engineering University of Texas Rio Grande Valley

The effect of temperature on the electrical conductivity （σ） and Seebeck coefficient （S） of n-type vapor grown carbon nanofibers （CNFs）and poly（vinylidene fluoride）(PVDF) melt-mixed with 15 wt%of those CNFs is *** 40°C,the CNFs show stable n-type character (S=-4.8μV·K-1) with anσof ca.165 S·m-1,while the PVDF/CNF composite film shows anσof ca.9 S·m-1and near-zero S (S=-0.5μV·K-1).This experimental reduction in S is studied by the density functional tight binding （DFTB） method revealing a contact electron transfer from the CNFs to the PVDF in the ***,in the temperature range from 40°C to 100°C,theσ（T） of the CNFs and PVDF/CNF film,successfully described by the 3D variable range hopping （VRH） model,is explained as consequence of a thermally activated backscattering *** the contrary,the S（T）from 40°C to 100°C of the PVDF/CNF film,which satisfactorily matches the model proposed for some multi-walled carbon nanotube （MWCNT）doped mats;however,it does not follow the increase in S（T） found for *** these findings are presented with the aim of discerning the role of these n-type vapor grown carbon nanofibers on theσand S of their melt-mixed polymer composites.

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied Mathematics and Mechanics(english edition) 2024年第3期45卷 407-424页

作者： M.SAFI M.VAKILIFARD M.j.MAHMOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of Mechanical and energy engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COMSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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Physical activity volume,frequency,and intensity:Associations with hypertension and obesity over 21 years in Australian women

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journal of Sport and Health Science 2024年第5期13卷 631-641页

作者： Gregore I.Mielke Ding Ding Shelley e.Keating Bruno P.Nunes Ruth Brady Wendy j.Brown School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Sydney School of Public Health Faculty of Medicine and HealthThe University of SydneySydneyNSW 2006Australia The Charles Perkins Centre The University of SydneySydneyNSW 2006Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia School of Nursing Federal University of PelotasPelotasRio Grande do Sul 96010-610Brazil Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia

Background:Optimal patterns of accrual of recommended levels of physical activity(PA)for prevention of hypertension and obesity are not *** overall aim of this study was to investigate whether different patterns of accumulation of PA are differentially associated with hypertension and obesity in Australian women over 21 ***,we investigated whether,for the same weekly volume of PA,the number of sessions(frequency)and vigorousness of PA(intensity)were associated with a reduction in the occurrence of hypertension and obesity in ***:Data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed(n=20,588;12%-16%with a Bachelor's or higher degree).Self-reported PA,hypertension,height,and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/*** estimating equation models with a 3-year lag model were used to investigate the association of PA volume(metabolic equivalent min/week)(none;33-499;500-999;≥1000,weekly frequency(none;1-2 times;3-4times;5-7 times;≥8 times),and the proportion of vigorous PA to total volume of PA(none;0%;1%-33%;34%-66%;67%-100%)with odds of hypertension and obesity from 2000 to ***:The cumulative incidence of hypertension was 6%in the 1973-1978 and 23%in the 1946-1951 cohort;27%of women in the 1973-1978;and 15%in the 1946-1951 cohort developed obesity over the ***,a higher volume of PA was associated with reduced odds of hypertension and *** the volume of PA was considered,the odds of hypertension did not vary according to the frequency or intensity of ***,increased proportion of vigorous PA to the total volume of PA was associated with a small additional reduction in the risk of obe ***:PA volume appears to be more important than the pattern of accumulation for the prevention of hypertension and *** more sessions,particularly of vigorous-intensity PA,may provide extr

关键词： Physical activity Frequency Intensity Incidences epidemiology Women

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Phanerozoic co-evolution of O2-CO2 and ocean habitability

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National Science Review 2024年第6期11卷 18-21页

作者： Zunli Lu Rosalind e.M.Rickaby jonathan L.Payne Ashley N.Prow Department of earth & environmental Sciences Syracuse University Department of earth Sciences University of Oxford Department of earth and Planetary Sciences Stanford University

Atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of earth have been hotly debated, but are generally considered independently.

关键词： CO2-CONCeNTRATING MeCHANISM OXYGeN eVOLUTION ANOXIA

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Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Advances in Atmospheric Sciences 2024年第8期41卷 1559-1568页

作者： Astrid e.j.OGILVIe Leslie A.KING Noel KeeNLYSIDe François COUNILLON Brynhildur DAVIÐSDÓTTIR Níels eINARSSON Sergey GULeV Ke FAN Torben KOeNIGK james R.MCGOODWIN Marianne H.RASMUSSON Shuting YANG Institute of Arctic and Alpine Research(INSTAAR) University of ColoradoBoulder CO 80303USA Stefansson Arctic Institute AkureyriÍS-600Iceland Royal Roads University BC V9B 5Y2Canada University of Bergen Bergen N-5007Norway Nansen environmental and Remote Sensing Centre Bergen N-5007Norway University of Iceland Reykjavík 102Iceland Shirshov Institute of Oceanology Moscow 117218Russia Moscow State University Moscow 11991Russia Chinese Academy of Sciences Beijing 100045China Swedish Meteorological and Hydrological Institute SE-60176 NorrköpingSweden Danish Meteorological Institute CopenhagenØ2100Denmark Obukhov Institute of Atmospheric Physics RAS119017MoscowRussia

This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sustainable Societies-ARCPATH(https://***/en/projects/finished-projects/arcpath). The disciplines represented in the project are related to climatology, anthropology, marine biology, economics, and the broad spectrum of social-ecological studies. Team members were drawn from the Nordic countries, Russia, China, the United States, and Canada. The project was transdisciplinary as well as interdisciplinary as it included collaboration with local knowledge holders. ARCPATH made significant contributions to Arctic research through an improved understanding of the mechanisms that drive climate variability in the Arctic. In tandem with this research, a combination of historical investigations and social, economic, and marine biological fieldwork was carried out for the project study areas of Iceland, Greenland, Norway, and the surrounding seas, with a focus on the joint use of ocean and sea-ice data as well as social-ecological drivers. ARCPATH was able to provide an improved framework for predicting the near-term variation of Arctic climate on spatial scales relevant to society, as well as evaluating possible related changes in socioeconomic realms. In summary, through the integration of information from several different disciplines and research approaches, ARCPATH served to create new and valuable knowledge on crucial issues, thus providing new pathways to action for Arctic communities.

关键词： Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Plant triterpenoid saponins function as susceptibility factors to promote the pathogenicity of Botrytis cinerea

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Molecular Plant 2024年第7期17卷 1073-1089页

作者： Francisco j.e.caray Amelia Felipo-Benavent Cristian j.Antonelli Begona Balaguer Maria Pilar Lopez-Gresa Pablo Vera Instituto de Biologia Molecular y Celular de Plantas Universidad Politecnica de Valencia-C.S.l.CCiudad Politecnica de la InnovacionEdificio 8Eacceso GIngeniero Fausto Elios/n46022ValenciaSpain

The gray mold fungus Botrytis cinerea is a necrotrophic pathogen that causes diseases in hundreds of plant species,including high-value *** polyxenous nature and pathogenic success are due to its ability to perceive host signals in its *** this study,we found that laticifer cells of euphorbia lathyris are a source of susceptibility factors required by *** to cause ***,poor-in-latex(pil)mutants,which lack laticifer cells,show full resistance to this pathogen,whereas lot-of-latex mutants,which produce more laticifer cells,are *** S factors are triterpenoid saponins,which are widely distributed natural products of vast structural *** downregulation of laticifer-specific oxydosqualene cyclase genes,which encode the first committed step enzymes for triterpene and,therefore,saponin biosynthesis,conferred disease resistance to ***,the Medicago truncatula Iha-1 mutant,compromised in triterpenoid saponin biosynthesis,showed enhanced ***,the application of different purified triterpenoid saponins pharmacologically complemented the diseaseresistant phenotype ofpil and hla-1 mutants and enhanced disease susceptibility in different plant *** found that triterpenoid saponins function as plant cues that signal transcriptional reprogramming in ***,leading to a change in its growth habit and infection strategy,culminating in the abundant formation of infection cushions,the multicellular appressoria apparatus dedicated to plant penetration and biomass destruction in *** together,these results provide an explanation for how plant triterpenoid saponins function as disease susceptibility factors to promote *** pathogenicity.

关键词： euphorbia lathyris laticifer cell latex appressorium infection cushion necrotrophic fungi

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Older Adult Compendium of Physical Activities:energy costs of human activities in adults aged 60 and older

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journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： erik A.Willis Stephen D.Herrmann Mary Hastert Chelsea L.Kracht Tiago V.Barreira john M.Schuna jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy j.Brown Barbara e.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MeT)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,embase,SPORTDiscus(eBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MeT_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MeT_(60+)values for older *** developed a website to present the OA Compendium MeT_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MeT_(60+)values for older adults for use in PA research and practice.

关键词： energy expenditure exercise MeT Older adults

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Clinical-based phenotypes in children with pediatric post-COVID-19 condition

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World journal of Pediatrics 2024年第7期20卷 682-691页

作者： Lieke C.e.Noij jelle M.Blankestijn Coen R.Lap Marlies A.van Houten Giske Biesbroek Anke-Hilse Maitland-van der Zee Mahmoud I.Abdel-Aziz johannes B.van Goudoever Mattijs W.Alsem Caroline L.H.Brackel Kim j.Oostrom Simone Hashimoto Suzanne W.j.Terheggen-Lagro Department of Pediatric Pulmonology and Allergy Amsterdam UMCLocation AMCEmma Children’s HospitalAmsterdam University Medical CenterRoom G2-222Meibergdreef 91105AZAmsterdamThe Netherlands Department of Pulmonary Medicine Amsterdam UMCAmsterdamThe Netherlands Department of Pediatrics Spaarne GasthuisHoofddorpThe Netherlands Department of Pediatrics Emma Children’s HospitalAmsterdam University Medical CenterAmsterdamThe Netherlands Department of Rehabilitation Medicine Amsterdam Movement SciencesMeibergdreef 9AmsterdamThe Netherlands Department of Paediatric Pulmonology Department of PaediatricsTergooi MCHilversumThe Netherlands Department of Child and Adolescent Psychiatry and Psychosocial Care Amsterdam UMCAmsterdam Reproduction and DevelopmentAmsterdamThe Netherlands

Background Pediatric post coronavirus disease 2019(COVID-19)condition(PPCC)is a heterogeneous syndrome,which can significantly affect the daily lives of *** study aimed to identify clinically meaningful phenotypes in children with PPCC,to better characterize and treat this *** Participants were children with physician-diagnosed PPCC,referred to the academic hospital Amsterdam UMC in the Netherlands between November 2021 and March *** factors and information on post-COVID symptoms,comorbidities,and impact on daily life were *** clusters were identified using an unsupervised and unbiased approach for mixed data *** Analysis of 111 patients(aged 3–18 years)revealed three distinct clusters within *** 1(n=62,median age=15 years)predominantly consisted of girls(74.2%).These patients suffered relatively more from exercise intolerance,dyspnea,and smell *** 2(n=33,median age=13 years)contained patients with an even gender distribution(51.5%girls).They suffered from relatively more sleep problems,memory loss,gastrointestinal symptoms,and *** 3(n=16,median age=11 years)had a higher proportion of boys(75.0%),suffered relatively more from fever,had significantly fewer symptoms(median of 5 symptoms compared to 8 and 10 for clusters 1 and 2 respectively),and experienced a lower impact on daily *** This study identified three distinct clinical PPCC phenotypes,with variations in sex,age,symptom patterns,and impact on daily *** findings highlight the need for further research to understand the potentially diverse underlying mechanisms contributing to post-COVID symptoms in children.

关键词： Adolescents Clusters Long COVID Pediatric Phenotypes Post-COVID syndrome

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Piezo1 expression in chondrocytes controls endochondral ossification and osteoarthritis development

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Bone Research 2024年第1期12卷 199-214页

作者： Laura j.Brylka Assil-Ramin Alimy Miriam e.A.Tschaffon-Müller Shan jiang Tobias Malte Ballhause Anke Baranowsky Simon von Kroge julian Delsmann eva Pawlus Kian eghbalian Klaus Püschel Astrid Schoppa Melanie Haffner-Luntzer David j.Beech Frank Timo Beil Michael Amling johannes Keller Anita Ignatius Timur A.Yorgan Tim Rolvien Thorsten Schinke Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf20246 HamburgGermany Department of Trauma and Orthopedic Surgery University Medical Center Hamburg-Eppendorf20246 HamburgGermany Institute of Orthopedic Research and Biomechanics University Medical Center UlmBadenWürttemberg89081 UlmGermany Department Legal Medicine University Medical Center Hamburg-Eppendorf20246 HamburgGermany Leeds Institute of Cardiovascular and Metabolic Medicine School of MedicineUniversity of LeedsLS29JT LeedsUK

Piezo proteins are mechanically activated ion channels,which are required for mechanosensing functions in a variety of cell *** we and others have previously demonstrated that the expression of Piezo1 in osteoblast lineage cells is essential for boneanabolic processes,there was only suggestive evidence indicating a role of Piezo1 and/or Piezo2 in *** we addressed the question if and how chondrocyte expression of the mechanosensitive proteins Piezo1 or Piezo2 controls physiological endochondral ossification and pathological osteoarthritis(OA)*** with chondrocyte-specific inactivation of Piezo1(Piezo1^(Col2a1Cre)),but not of Piezo2,developed a near absence of trabecular bone below the chondrogenic growth plate ***,all Piezo1^(Col2a1Cre) animals displayed multiple fractures of rib bones at 7 days of age,which were located close to the growth *** skeletal growth was only mildly affected in these mice,OA pathologies were markedly less pronounced compared to littermate controls at 60 weeks of ***,when OA was induced by anterior cruciate ligament transection,only the chondrocyte inactivation of Piezo1,not of Piezo2,resulted in attenuated articular cartilage ***,osteophyte formation and maturation were also reduced in Piezo1^(Col2a1Cre) *** further observed increased Piezo1 protein abundance in cartilaginous zones of human ***,we identified Ptgs2 and Ccn2 as potentially relevant Piezo1 downstream genes in ***,our data do not only demonstrate that Piezo1 is a critical regulator of physiological and pathological endochondral ossification processes,but also suggest that Piezo1 antagonists may be established as a novel approach to limit osteophyte formation in OA.

关键词： Piezo1 markedly ossification

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elucidating regulatory processes of intense physical activity by multi-omics analysis

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Military Medical Research 2024年第4期11卷 479-499页

作者： ernesto S.Nakayasu Marina A.Gritsenko Young-Mo Kim jennifer e.Kyle Kelly G.Stratton Carrie D.Nicora Nathalie Munoz Kathleen M.Navarro Daniel Claborne Yuqian Gao Karl K.Weitz Vanessa L.Paurus Kent j.Bloodsworth Kelsey A.Allen Lisa M.Bramer Fernando Montes Kathleen A.Clark Grant Tietje justin Teeguarden Kristin e.Burnum-johnson Biological Sciences Division Pacific Northwest National LaboratoryRichlandWA 99352USA environmental and Molecular Sciences Division Pacific Northwest National LaboratoryRichlandWA 99352USA Centers for Disease Control and Prevention National Institute for Occupational Safety and HealthWestern States DivisionDenverCO 80204USA Computational Analytics Division Pacific Northwest National LaboratoryRichlandWA 99352USA National Security Directorate Pacific Northwest National LaboratoryRichlandWA 99352USA Los Angeles County Fire Department Los AngelesCA 90063USA Centers for Disease Control and Prevention National Institute for Occupational Safety and HealthRespiratory Health DivisionMorgantownWV 26505USA environmental and Molecular Toxicology Oregon State UniversityCorvallisOR 97331USA

Background:Physiological and biochemical processes across tissues of the body are regulated in response to the high demands of intense physical activity in several occupations,such as firefighting,law enforcement,military,and sports.A better understanding of such processes can ultimately help improve human performance and prevent illnesses in the work ***:To study regulatory processes in intense physical activity simulating real-life conditions,we performed a multi-omics analysis of 3 biofluids(blood plasma,urine,and saliva)collected from 11 wildland firefighters before and after a 45 min,intense exercise *** profiles ***-exercise were compared by Student’s t-test followed by pathway analysis and comparison between the different omics ***:Our multi-omics analysis identified and quantified 3835 proteins,730 lipids and 182 metabolites combining the 3 different types of *** blood plasma analysis revealed signatures of tissue damage and acute repair response accompanied by enhanced carbon metabolism to meet energy *** urine analysis showed a strong,concomitant regulation of 6 out of 8 identified proteins from the renin-angiotensin system supporting increased excretion of catabolites,reabsorption of nutrients and maintenance of fluid *** saliva,we observed a decrease in 3 pro-inflammatory cytokines and an increase in 8 antimicrobial peptides.A systematic literature review identified 6 papers that support an altered susceptibility to respiratory ***:This study shows simultaneous regulatory signatures in biofluids indicative of homeostatic maintenance during intense physical activity with possible effects on increased infection susceptibility,suggesting that caution against respiratory diseases could benefit workers on highly physical demanding jobs.

关键词： Multi-omics analysis Intense exercise Human performance Biofluids Metabolism Immunity

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