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Influence of curing conditions on the shrinkage behavior of three-dimensional printed concrete formwork

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1225-1236页

作者： m.BEkAERT k.van TITTELBOOm G.de SCHUTTER magnel-vandepitte Laboratory for structural Engineering and Building materials Department of Structural Engineering and Building MaterialsFaculty of Engineering and ArchitectureGhent UniversityGhent 60 B-9052Belgium

The use of three-dimensional(3D)printed concrete as formwork is becoming more widely applied within the ***,the technology is still not optimized and there are many reports of preliminary cracking during the curing of cast *** is believed to result from differential shrinkage between the printed and cast *** cracks(in the printed concrete or at the interface between the infill and printed concrete)form a preferential path for aggressive substances and can reduce the durability of the combined concrete *** ensure the desired service life of the structure,it is important that the differential shrinkage between cast and printed concrete is *** study investigated the effect of curing conditions on the differential shrinkage behavior of 3D and cast *** influence of prewetting of the dry-cured 3D printed formwork was also *** the experimental program,a vibrated and self-compacting concrete were used as cast *** 3D printed formwork was produced and combined with cast concrete to simulate a concrete *** formwork was cured for 1,7,or 28 d exposed to the air(relative humidity:60%or 95%)or submerged in *** length change of the combined elements was observed over 56 d after concrete casting and throughout the thickness of the *** show that increasing the curing period in dry conditions of the printed concrete leads to an expansion of the formwork on the first day after *** expansion leads to a non-uniform strain evolution throughout the curing period of the combined *** concrete formwork stored in wet conditions does not expand after the casting process but tends to show a decreasing linear deformation within the whole elements.

关键词： 3D concrete printing formwork shrinkage curing

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面向城市交通噪声控制的树种筛选与种植策略

应用声学 2024年第4期43卷 843-853页

作者：李朦朦 Timothy van renterghem 孟琪 Dick Botteldooren 康健哈尔滨工业大学建筑与设计学院寒地城乡人居环境科学与技术工业和信息化部重点实验室哈尔滨150001 比利时根特大学工程与建筑学院信息技术系Waves研究组根特9052 英国伦敦大学学院环境设计与工程学院伦敦WC1H 0NN

植物降噪是一种减碳且低成本的降噪方式,可有效改善城市声环境。然而现存植物降噪影响因素与预测模型主要集中在植物群落层面,忽略了树种间差异在不同频率噪声控制过程中的重要作用,难以满足城市交通噪声有效防控的需求。基于此,该研究... 详细信息

植物降噪是一种减碳且低成本的降噪方式,可有效改善城市声环境。然而现存植物降噪影响因素与预测模型主要集中在植物群落层面,忽略了树种间差异在不同频率噪声控制过程中的重要作用,难以满足城市交通噪声有效防控的需求。基于此,该研究以植物树干为切入点,提出一种量化树干与树皮粗糙度的方法,针对交通噪声频谱特征系统测量13种树种的吸收作用,并模拟降噪效果。研究首先测得树干吸声系数的频谱特征,确定了树干主要吸声频率范围与交通噪声频率分布具备较好的一致性;其次,从树种视角分析视觉因素与测试获取因素两个层面对树干吸声效果有影响的主要因素;最后,通过模拟对比分析15 m宽植物带种植不同树种的降噪效果,发现相差∼0.9 dBA,证明了种植吸声系数高的树种对交通噪声控制的有效性。以期从树形、树干吸声效果、树种生长速度以及种植方式等方面,提出应对城市交通噪声污染的树种筛选依据与设计策略。

关键词：噪声控制交通噪声吸声系数自然降噪途径

A new perspective on intervertebral disc calcification—from bench to bedside

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Bone Research 2024年第1期12卷 50-61页

作者： Emanuel J.Novais Rajkishen Narayanan Jose A.Canseco koen van de Wetering Christopher k.kepler Alan S.Hilibrand Alexander R.Vaccaro makarand V.Risbud Department of Orthopaedic Surgery Sidney Kimmel Medical CollegeThomas Jefferson UniversityPhiladelphiaPAUSA Unidade Local de Saúde do Litoral Alentejano Orthopedic DepartmentSantiago do CacémPortugal Rothman Orthopedic Institute at Thomas Jefferson University PhiladelphiaPAUSA

Disc degeneration primarily contributes to chronic low back and neck ***,there is an urgent need to understand the spectrum of disc degeneration phenotypes such as fibrosis,ectopic calcification,herniation,or mixed *** these phenotypes,disc calcification is the least *** calcification,by definition,is the pathological mineralization of soft tissues,widely studied in the context of conditions that afflict vasculature,skin,and ***,disc calcification is associated with poor surgical outcomes and back pain refractory to conservative *** is frequently seen as a consequence of disc aging and progressive degeneration but exhibits unique molecular and morphological characteristics:hypertrophic chondrocyte-like cell differentiation;TNAP,ENPP1,and ANk upregulation;cell death;altered Pi and PPi homeostasis;and local *** studies in mouse models have provided a better understanding of the mechanisms underlying this *** is essential to recognize that the presentation and nature of mineralization differ between AF,NP,and EP ***,the combination of anatomic location,genetics,and environmental stressors,such as aging or trauma,govern the predisposition to ***,the systemic regulation of calcium and Pi metabolism is less important than the local activity of PPi modulated by the ANk-ENPP1 axis,along with disc cell death and differentiation *** there is limited understanding of this phenotype,understanding the molecular pathways governing local intervertebral disc calcification may lead to developing disease-modifying drugs and better clinical management of degeneration-related pathologies.

关键词： degeneration metabolism intervertebral

Analysis of the Impact of the Blazhko Effect Both on the van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri F.L.Sefyani A.Benhida Z.Benkhaldoun k.kolenberg k.Chafouai A.Habib m.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPm ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

Genome-wide Studies Reveal Genetic Risk Factors for Hepatic Fat Content

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 57-68页

作者： Yanni Li Eline H.van den Berg Alexander kurilshikov Dasha V.Zhernakova Ranko Gacesa Shixian Hu Esteban A.Lopera-maya Alexandra Zhernakova Lifelines Cohort Study Vincent E.de meijer Serena Sanna Robin P.F.Dullaart Hans Blokzijl Eleonora A.m.Festen Jingyuan Fu Rinse k.Weersma Department of Gastroenterology and Hepatology University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Genetics University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China Laboratory of Genomic Diversity Center for Computer TechnologiesITMO UniversitySaint Petersburg 199034Russia Institute of Precision medicine the First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Department of Surgery Section of Hepatobiliary Surgery and Liver TransplantationUniversity of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Endocrinology University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands Department of Pediatrics University of GroningenUniversity Medical Center GroningenGroningen 9713 GZThe Netherlands 不详

Genetic susceptibility to metabolic associated fatty liver disease(mAFLD)is complex and poorly *** characterization of the genetic background of hepatic fat content would provide insights into disease etiology and causality of risk *** performed genome-wide association study(GWAS)on two noninvasive definitions of hepatic fat content:magnetic resonance imaging proton density fat fraction(mRI-PDFF)in 16,050 participants and fatty liver index(FLI)in 388,701 participants from the United kingdom(Uk)Biobank(UkBB).Heritability,genetic overlap,and similarity between hepatic fat content phenotypes were analyzed,and replicated in 10,398 participants from the University medical Center Groningen(UmCG)Genetics Lifelines Initiative(UGLI).meta-analysis of GWASs of mRI-PDFF in UkBB revealed five statistically significant loci,including two novel genomic loci harboring CREB3L1(rs72910057-T,P=5.40E−09)and GCm1(rs1491489378-T,P=3.16E−09),respectively,as well as three previously reported loci:PNPLA3,Tm6SF2,and *** of FLI in UkBB identified 196 genome-wide significant loci,of which 49 were replicated in UGLI,with top signals in ZPR1(P=3.35E−13)and FTO(P=2.11E−09).Statistically significant genetic correlation(rg)between mRI-PDFF(UkBB)and FLI(UGLI)GWAS results was found(rg=0.5276,P=1.45E−03).Novel mRI-PDFF genetic signals(CREB3L1 and GCm1)were replicated in the FLI *** identified two novel genes for mRI-PDFF and 49 replicable loci for *** a difference in hepatic fat content assessment between mRI-PDFF and FLI,a substantial similar genetic architecture was *** is identified as an easy and reliable approach to study hepatic fat content at the population level.

关键词： Hepatic fat content mAFLD Genome-wide association study Fatty liver index magnetic resonance imaging proton density fat fraction

Exercise training improves long-term memory in obese mice

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Life metabolism 2024年第1期3卷 37-50页

作者： Oliver k.Fuller Casey L.Egan Tina L.Robinson Nimna Perera Heidy k.Latchman Lauren V.Terry Emma D.mcLennan Carolina Chavez Emma L.Burrows John W.Scott Robyn m.murphy Henriette van Praag martin Whitham mark A.Febbraio monash Institute of Pharmaceutical Sciences Monash UniversityMelbourneVictoria3052Australia La Trobe Institute for molecular Science La Trobe UniversityMelbourneVictoria3086Australia Florey Institute of Neuroscience and mental Health University of MelbourneMelbourneVictoria3052Australia Department of Biomedical Sciences Charles E.Schmidt College of Medicineand Stiles-Nicholson Brain InstituteFlorida Atlantic UniversityJupiterFL 33458United States College of Life and Environmental Sciences University of BirminghamEdgbastonBirmingham B152TTUnited Kingdom

Obesity has been linked to a range of pathologies,including *** contrast,regular physical activity is associated with the prevention or reduced progression of ***,physical activity can improve memory and spatial cognition,reduce age-related cognitive decline,and preserve brain volume,but the mechanisms are not fully ***,we investigated whether any detrimental effects of high-fat diet(HFD)-induced obesity on cognition,motor behavior,adult hippocampal neurogenesis,and brain-derived neurotrophic factor(BDNF)could be mitigated by voluntary exercise training in male C57Bl/6 ***-induced impairment of motor function was not reversed by ***,voluntary wheel running improved long-term memory and increased hippocampal neurogenesis,suggesting that regular physical activity may prevent cognitive decline in obesity.

关键词： obesity exercise cognition

Effect of Thermal Cycles on Creep Behavior of Bituminous Binder in Hot Regions

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Journal of Civil Engineering and Architecture 2024年第7期18卷 334-339页

作者： Bachir Glaoui mahdjoub Bendjima m'hamed merbouh martin van de Ven Laboratoire de la Fiabilité des matériaux et Structures en Régions Sahariennes(FImAS) Université de Béchar B.P.417Béchar08000Algérie Laboratory of Road and Railway Engineering TU DelftP.O.Box 50482600 GA DelftThe Netherlands

This research is devoted to the study of creep behavior of asphalt binder in hot *** binder was subjected to thermal cycles due to the variation of temperature from day to *** cycles produce a heating-cooling *** evaluate the effect of climate change in laboratory,the DSR(dynamic shear rheometer)was used,and the results found with the nine samples were *** thermal cycles led to aging and therefore hardening of the ***,a rheological model was proposed that can represent the curves obtained experimentally,where it is able to describe the creep behavior of binders tested.A new model is proposed that correlates well with the experimental curves,which is called A+2 k.

关键词： Bitumen temperature heating/cooling DSR BBR model

中国社会陌生人之间合作行为的变迁:基于社会困境研究的元分析(1999~2019)

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心理学报 2024年第9期56卷 1159-1175页

作者：苑明亮伍俊辉金淑娴林靓寇彧 Paul A.m.van Lange 安徽农业大学人文社会科学学院心理学系合肥230036 中国科学院心理研究所行为科学重点实验室北京100101 中国科学院大学心理学系北京100049 萨塞克斯大学心理学院英国布莱顿BN19RH 北京师范大学发展心理研究院应用实验心理北京市重点实验室心理学国家级实验教学示范中心(北京师范大学)北京100875 阿姆斯特丹自由大学脑与行为研究院实验与应用心理学系荷兰阿姆斯特丹1081BT

陌生人间的合作行为对于解决社会公共问题,应对世界百年未有之大变局意义重大。本研究采用横断历史元分析方法,基于1999~2019年间开展的254项使用社会困境范式测量我国陌生人间合作行为的研究(共302个合作率,29249名被试,平均年龄:18~28... 详细信息

陌生人间的合作行为对于解决社会公共问题,应对世界百年未有之大变局意义重大。本研究采用横断历史元分析方法,基于1999~2019年间开展的254项使用社会困境范式测量我国陌生人间合作行为的研究(共302个合作率,29249名被试,平均年龄:18~28岁),探讨了中国社会中合作行为的变迁及一些社会发展指标在其中的解释作用,并比较中美两国的合作行为变迁趋势。结果表明,中国人的合作行为水平随时间而上升,一些社会发展指标(人均国内生产总值、城市化率、高等教育水平、互联网普及率等)可能是其上升的社会变迁基础。中美两国合作行为表现出相似的上升趋势,但中国的在更短时间内有更大上升幅度。研究结果对提振民众信心具有重要意义。

关键词：合作行为社会资本社会困境横断历史元分析社会变迁

Enhanced Electrical Properties of Bi2-xSbxTe3 Nanoflake Thin Films Through Interface Engineering

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ENERGY & ENVIRONmENTAL mATERIALS 2024年第6期7卷 359-366页

作者： Wu, Xudong Ding, Junjie Cui, Wenjun Lin, Weixiao Xue, Zefan Yang, Zhi Liu, Jiahui Nie, Xiaolei Zhu, Wanting van Tendeloo, Gustaaf Sang, Xiahan Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430070 Peoples R China Wuhan Univ Technol NRC Nanostruct Res Ctr Wuhan 430070 Peoples R China Univ Antwerp EMAT Electron Microscopy Mat Sci Groenenborgerlaan 171 B-2023 Antwerp Belgium

The structure-property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure. Designing thermoelectric materials with a simple, structurally-uniform interface provides a facile way to understand how these interfaces influence the transport properties. Here, we synthesized Bi2-xSbxTe3 (x = 0, 0.1, 0.2, 0.4) nanoflakes using a hydrothermal method, and prepared Bi2-xSbxTe3 thin films with predominantly (0001) interfaces by stacking the nanoflakes through spin coating. The influence of the annealing temperature and Sb content on the (0001) interface structure was systematically investigated at atomic scale using aberration-corrected scanning transmission electron microscopy. Annealing and Sb doping facilitate atom diffusion and migration between adjacent nanoflakes along the (0001) interface. As such it enhances interfacial connectivity and improves the electrical transport properties. Interfac reactions create new interfaces that increase the scattering and the Seebeck coefficient. Due to the simultaneous optimization of electrical conductivity and Seebeck coefficient, the maximum power factor of the Bi1.8Sb0.2Te3 nanoflake films reaches 1.72 mW m(-1) k-2, which is 43% higher than that of a pure Bi2Te3 thin film.

关键词： Bi2Te3 nanoflakes interface engineering scanning transmission electron microscopy thermoelectric thin film HIGH-THERmOELECTRIC PERFORmANCE POWER-GENERATION 2D mATERIALS GROWTH BISmUTH TELLURIDE NANOPLATELETS mECHANISmS NANOSHEETS mAGNETISm