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表面粗糙和带槽的湿式离合器接合的有限元模型

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传动技术 2015年第2期29卷 39-47页

作者： e.j.berger F.Sadeghi C.M.Krousgrill school of Mechanical engineer-ing purdue University

已经开发了一个有限元模型,研究表面粗糙和带槽纸质可渗透的湿式离合器的接合特性。采用有限元方法(Galerkin)离散修正雷诺和力平衡方程式,采用等参量方程式解所描述的有关内何学。通过Patir和Cheng(1978)的通用流量模型模拟表面粗糙度... 详细信息

已经开发了一个有限元模型,研究表面粗糙和带槽纸质可渗透的湿式离合器的接合特性。采用有限元方法(Galerkin)离散修正雷诺和力平衡方程式,采用等参量方程式解所描述的有关内何学。通过Patir和Cheng(1978)的通用流量模型模拟表面粗糙度的影响。在表面粗糙状况下,采用Greenwond和William son(1966)方法计算负荷分配,采用开发的有限元模型研究所加负荷的影响,以及湿式离合器摩擦材料的渗透率和槽出入口尺寸的接合特性(即转矩、油压、接合时间和油膜厚度)。研究结果表明,所加负荷、摩擦材料渗透率和槽宽度对接合特性的影响显著。高的配合面压力增大了峰值和减少了接合时间但显著增大了峰值转矩,宽油槽减少峰值转矩和增加了接合时间。对于本模型油槽深度对接合特性的影响不太明显。

关键词：有限元模型摩擦材料湿式离合器数学模型

表面粗糙和带槽的湿式离合器接合的有限元模型

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传动技术 2015年第1期29卷 39-42页

作者： e.j.berger F.Sadeghi C.M.Krousgrill school of Mechanical engineering purdue University

关键词：有限元模型摩擦材料湿式离合器数学模型

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： j.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Malargüe Site Remediation:A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年第10期58卷 2088-2094页

作者： BARARI e DíAZ j G GIOMIA KeMPF R A National Atomic energy Commission Av.Del Libertador 8250Ciudad Autónoma de Buenos AiresC1429BNPArgentina

Comisión Nacional de energía Atómica (CNeA) has the responsibility for restoring uranium mining facilities once the operations have ***,within its environmental Program and in compliance with its legal responsibilities,decides to implement a restoration project for all sites related to the mining and processing of uranium *** Malargüe Site is located within the Province of Mendoza in the city of Malargü*** is the first site to successfully complete its *** activities consist of relocation of tailings to an engineering *** tailings management(encapsulation) and rehabilitation of the area was finished in june *** remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for *** objective of the encapsulation of the mineral tails is to isolate them from the environment,also proceeding with the decontamination and rehabilitation of the area (landscaping,post-closure monitoring and 20 years monitoring period).encapsulation consisted of the construction of a containment cell for the mine tailings,to isolate them and prevent pollutants from entering the environment through the transfer *** clean the impacted areas,the soil was removed,it was incorporated into the encapsulation,and the filling was carried out with natural soils from the *** prevents radon transfer to the environment,as ^(222)Ra is an alpha emitter with a half-life of four days,which produces its own radioactive *** progeny are solids,and when a ^(222)Ra nucleus emits an alpha particle into the air,the resulting ^(218)Po nucleus,momentarily electrically charged,adheres to any dust *** prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon *** tasks mentioned make it possible to decrease radon emanation,reduce radiological risks to the public and pre

关键词： remediation radionuclide transfer tailings encapsulation solution sustainable

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo j.Fernandez Mariana e.Carro Paulo e.Llambías Grupo de Investigacion en ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CjS Density-dependence Survival Troglodytes aedon bonariae

Femoral Access with Ultrasound-Guided Puncture and Z-Stitch Hemostasis for Adults with Congenital Heart Diseases Undergoing electrophysiological Procedures

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Congenital Heart Disease 2024年第1期19卷 85-92页

作者： Fu Guan Matthias Gass Florian berger Heiko Schneider Firat Duru Thomas Wolber Arrhythmia and electrophysiology Division Department of CardiologyUniversity Heart Center ZurichZurichSwitzerland Children’s Research Center Zurich University Children’s HospitalZurichSwitzerland Center for Integrative Human Physiology University of ZurichZurichSwitzerland

Aims:Although the application of ultrasound-guided vascular puncture and Z-stitch hemostasis to manage femoral access has been widely utilized,there is limited data on this combined application in adult congenital heart disease(ACHD)patients undergoing electrophysiological(eP)*** sought to evaluate the safety and efﬁcacy of ultrasound-guided puncture and postprocedural Z-stitch hemostasis for ACHD patients under-going eP *** and Results:The population of ACHD patients undergoing transfemoral eP pro-cedures at the University of Zurich Heart Center between january 2019 and December 2022 was observed and *** the study period,femoral access(left/right,arterial/venous)was performed under real-time ultrasound *** the end of the procedure,a single Z-stitch was performed at the puncture *** eval-uated the incidence of in-hospital complications associated with femoral access puncture in this *** 101 patients who had a total of 147 previous ipsilateral vascular punctures(mean 1.5 per person),100 patients underwent successful femoral vascular access for eP *** median age of the patients was 47±15 years and 34(34%)were male.Z-stitches were performed after the procedure in 100 patients with 303 femoral vascular accesses(mean 3 punctures per person).No patient developed vascular puncture relevant inguinal hematoma,pseudo aneurysm,arteriovenousﬁstula,venous or arterial ***:In ACHD patients undergoing eP procedures,optimal femoral access management can be achieved with ultra-sound-guided puncture and postprocedural Z-stitch hemostasis.

关键词： Congenital heart disease cardiac electrophysiology cardiac catheterization femoral access hemostasis

Two imprinted genes primed by DeMeTeR in the central cell and activated by WRKY10 in the endosperm

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journal of Genetics and Genomics 2024年第8期51卷 855-865页

作者： Ke Yang Yuling Tang Yue Li Wenbin Guo Zhengdao Hu Xuanpeng Wang Frédéric berger jing Li College of Life Science and Technology Huazhong Agricultural UniversityWuhanHubei 430070China Sanya Institute of Breeding and Multiplication Hainan UniversitySanyaHainan 572025China School of Tropical Agriculture and Forestry Hainan UniversityHaikouHainan 570228China Hainan Yazhou Bay Seed Laboratory SanyaHainan 572025China Gregor Mendel Institute Austrian Academy of SciencesVienna BioCenter1030 ViennaAustria

The early development of the endosperm is crucial for balancing the allocation of maternal nutrients to *** process is believed to be evolutionarily associated with genomic imprinting,resulting in parentally biased allelic gene *** Fertilization Independent Seed(FIS)genes,the number of imprinted genes involved in early endosperm development and seed size determination remains *** study introduces early endosperm-expressed HAIKU(IKU)downstream Candidate F-box 1(ICF1)and ICF2 as maternally expressed imprinted genes(MeGs)in Arabidopsis *** these genes are also demethylated by DeMeTeR(DMe)in the central cell,their activation differs from the direct DMe-mediated activation seen in classical MeGs such as the FIS ***,ICF maternal alleles carry pre-established hypomethylation in their promoters,priming them for activation by the WRKY10 transcription factor in the *** the contrary,paternal alleles are predominantly suppressed by CG ***,we find that ICF genes partially contribute to the small seed size observed in iku *** discovery reveals a two-step regulatory mechanism that highlights the important role of conventional transcription factors in the activation of imprinted genes,which was previously not fully ***,the mechanism provides a new dimension to understand the transcriptional regulation of imprinting in plant reproduction and development.

关键词： Imprinting epigenetics DNAmethylation Seedsize endosperm

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.D.james j.e.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Risk prediction of advanced colorectal neoplasia varies by race and neighbourhood socioeconomic status

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Family Medicine and Community Health 2024年第S2期12卷 26-33页

作者： Xiangqing Sun Zhengyi Chen Gregory S Cooper Nathan A berger Claudia Coulton Li Li Department of Family Medicine University of VirginiaCharlottesvilleVirginiaUSA Department of Population and Quantitative Health Sciences Case Western Reserve UniversityClevelandOhioUSA University Hospitals Cleveland Medical Center ClevelandOhioUSA Case Comprehensive Cancer Center ClevelandOhioUSA jack Joseph and Morton Mandel School of Applied Social SciencesCase Western Reserve UniversityClevelandOhioUSA

Objective Neighbourhood deprivation increases the risk of colorectal neoplasia and contributes to racial disparities observed in this *** race-specific advanced colorectal neoplasia(ACN)prediction models that include neighbourhood socioeconomic status has the potential to improve the accuracy of *** The study includes 1457 european Americans(eAs)and 936 African Americans(AAs)aged 50–80 years undergoing screening ***-specific ACN risk prediction models were developed for eAs and AAs,*** Deprivation Index(ADI),derived from 17 variables of neighbourhood socioeconomic status,was evaluated by adding it to the ACN risk prediction *** accuracy was evaluated by concordance statistic(C-statistic)for discrimination and Hosmer-Lemeshow goodness-of-fit test for *** With fewer predictors,the eA-specific and AA-specific prediction models had better prediction accuracy in the corresponding race/ethnic subpopulation than the overall *** with the overall model which had poor calibration(P_(Calibration)=0.053 in the whole population and P_(Calibration)=0.011 in AAs),the eA model had C-statistic of 0.655(95%CI 0.594 to 0.717)and P_(Calibration)=0.663;and the AA model had C-statistic of 0.637((95%CI 0.572 to 0.702)and P_(Calibration)=*** was a significant predictor of ACN in eAs(OR=1.24((95%CI 1.03 to 1.50),P=0.029),but not in AAs(OR=1.07((95%CI 0.89 to 1.28),P=0.487).Adding ADI to the eA-specific ACN prediction model substantially improved ACN calibration accuracy of the prediction across area deprivation groups(P_(Calibration)=0.924 with ADI vs P_(Calibration)=0.140 without ADI)in *** Neighbourhood socioeconomic status is an important factor to consider in ACN risk prediction ***,non-race-specific prediction models have poor ***-specific prediction models incorporating neighbourhood socioeconomic factors are needed to improve ACN predicti

关键词： colorectal neoplasia prediction