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Low-temperature densification of high-entropy(Ti,Zr,Nb,Ta,Mo)C-Co composites with high hardness and high toughness

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j.urnal of Advanced Ceramics 2022年第5期11卷 805-813页

作者： Si-Chun LUO Wei-Ming GUO kevin PLUCKNETT Hua-Tay LIN School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China School of Mechanical and Electronic Engineering Pingxiang UniversityPingxiang 337000China Department of Process Engineering and Applied Science Dalhousie UniversityHalifax B3J1ZICanada

In order to prepare high toughness(Ti,Zr,Nb,Ta,Mo)C ceramics at low temperatures while maintaining high hardness,a liquid-phase sintering process combined with Co-based liquid-phase extrusion strategy was adopted in this *** densification temperature can be lowered to 1350℃,which is much lower than the solid-state sintering temperature(~2000℃)generally employed for high-entropy carbide *** sintered at 1550℃and 30 MPa applied pressure,part of the Co-based liquid-phase was squeezed out of the graphite mold,such that only~3.21 vol%of Co remained in the high-entropy *** to the Co-free solid-state sintered(Ti,Zr,Nb,Ta,Mo)C ceramics,prepared at 2000℃and 35 MPa,the hardness was slightly decreased from 25.06±0.32 to 24.11±0.75 GPa,but the toughness was increased from 2.25±0.22 to 4.07±0.13 MPa·m^(1/2).This work provides a new strategy for low-temperature densification of high-entropy carbides with both high hardness and high toughness.

关键词： high-entropy carbide ceramics liquid-phase sintering microstructure grain size mechanical properties

Blood pressure-related white matter microstructural disintegrity and associated cognitive function impairment in asymptomatic adults

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Stroke & Vascular Neurology 2023年第5期8卷 358-367页

作者： j.lián N Acosta Stefan P Haider Cyprien Rivier Audrey C Leasure kevin N Sheth Guido j.Falcone Seyedmehdi Payabvash Department of Neurology Yale School of MedicineNew HavenConnecticutUSA Department of Radiology and Biomedical Imaging Yale School of MedicineNew HavenConnecticutUSA Department of Otorhinolaryngology Ludwig Maximilians University MunichMunchenGermany

Background and obj.ctives We aimed to investigate the white matter(WM)microstructural/cytostructural disintegrity patterns related to higher systolic blood pressure(SBP),and whether they mediate SBP effects on cognitive performance in middle-aged *** Using the UK Biobank study of community-dwelling volunteers aged 40-69 years,we included participants without a history of stroke,dementia,demyelinating disease or traumatic brain *** investigated the association of SBP with MRI diffusion metrics:fractional anisotropy(FA),mean diffusivity(MD),intracellular volume fraction(a measure of neurite density),isotropic(free)water volume fraction(ISOVF)and orientation dispersion across WM ***,we determined whether WM diffusion metrics mediated the effects of SBP on cognitive *** We analysed 31363 participants-mean age of 63.8 years(SD:7.7),and 16523(53%)*** SBP was associated with lower FA and neurite density,but higher MD and *** different WM tracts,diffusion metrics of the internal capsule anterior limb,external capsule,superior and posterior corona radiata were most affected by higher *** seven cognitive metrics,SBP levels were only associated with‘fluid intelligence’(adj.sted p<0.001).In mediation analysis,the averaged FA of external capsule,internal capsule anterior limb and superior cerebellar peduncle mediated 13%,9%and 13%of SBP effects on fluid intelligence,while the averaged MD of external capsule,internal capsule anterior and posterior limbs,and superior corona radiata mediated 5%,7%,7%and 6%of SBP effects on fluid intelligence,*** Among asymptomatic adults,higher SBP is associated with pervasive WM microstructure disintegrity,partially due to reduced neuronal count,which appears to mediate SBP adverse effects on fluid *** metrics of select WM tracts,which are most reflective of SBP-related parenchymal damage and cognitive impairment,may serve as imaging biomarkers to

关键词： capsule Blood impairment

Isolated left ventricular apical hypoplasia:Systematic review and analysis of the 37 cases reported so far

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世界临床病例杂志 2023年第23期11卷 5494-5503页

作者： Pier Paolo Bassareo Sophie Duignan Adam j.mes Esme Dunne Colin j.McMahon kevin P Walsh University College of Dublin School of Medicine and Department of Cardiology at Mater Misericordiae University HospitalDublin D07 R2WYIreland Department of Cardiology Children's Health CrumlinDublin D12 N512Ireland University College of Dublin School of Medicine and Department of CardiologyChildren's Health IrelandDublin D12 N512Ireland

BACKGROUND Isolated left ventricular apical hypoplasia(ILVAH),also known as truncated left ventricle(LV),is a very unusual *** is characterised by a truncated,spherical,and non-apex forming *** true apex is occupied by the right *** to the rarity of the disease,j.st a few case reports and limited case series have been published in the *** To analysing the so far 37 reported ILVAH cases *** The electronic databases PubMed and Scopus were investigated from their establishment up to December 13,*** The maj.rity of cases reported occurred in males(52.7%).Mean age at diagnosis was 26.1±19.6 *** than a third of the patients were asymptomatic(35.1%).The most usual clinical presentation was breathlessness(40.5%).The most commonly detected electrocardiogram changes were T wave abnormalities(29.7%)and right axis deviation with poor R wave progression(24.3%).Atrial fibrillation/flutter was detected in 24.3%.Echocardiography was performed in 97.3%of cases and cardiac MRI in 91.9%of *** fraction was reduced in more than a half of patients(56.7%).An associated congenital heart disease was found in 16.2%.Heart failure therapy was administered in 35.1%of *** outcome was favorable in the vast maj.rity of patients,with j.st one *** ILVAH is a multifaceted entity with a so far unpredictable course,ranging from benign until the elderly to sudden death during adolescence.

关键词： Isolated left ventricular apical hypoplasia Truncated left ventricle Electrocardiography Echocardiography Cardiac magnetic resonance imaging Heart failure

Aqueous synthesis of bright near-infrared-emitting Zn-Cu-In-Se quantum dots for multiplexed detection of tumor markers

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Nano Research 2022年第9期15卷 8351-8359页

作者： Hui Liu Peng Cai kevin j.McHugh Collin F.Perkinson Laishuo Li Shuna Wang Wei Wang Mingxia j.ao Xiliang Luo Lihong j.ng Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Qingdao j.chuang Environmental Protection Group Co. Ltd.Qingdao 266107China Department of Bioengineering Rice University6100 Main StreetMS-142HoustonTX 77005USA Department of Chemistry Massachusetts Institute of Technology77 Massachusetts AvenueCambridgeMA 02139USA Key Laboratory of Colloid Interface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Aqueous synthesis is a green but challenging pathway to produce cadmium-free,bright,and near-infrared(NIR)emitting quantum dots(QDs).Herein,we develop a straightforward aqueous phase approach to prepare Zn-Cu-In-Se QDs with tunable emission from 630 to 800 nm through varying the molar ratio of Zn and *** ultrasmall nanoparticle size remains nearly fixed(~2.6 nm)when the QD composition is varied,allowing for the effects of composition on the optical properties of QDs to be decoupled from the impact of particle *** leveraging the off-stoichiometric effect on photoluminescence(PL),Zn-Cu-In-Se QDs with a Zn:Cu molar ratio of 1.0 show a long PL decay lifetime of 211 ns and an absolute photoluminescence quantum yield(PLQY)of 14.2%.The PLQY is further enhanced by overcoating a ZnS shell,reaching up to 25.8%.Based on the bright,biocompatible,and emission-tunable QDs,nanoprobes with targeting capability for multiple tumor markers are further constructed and employed to simultaneously ascertain targets in the cytoplasm and cell *** study provides a green and effective strategy for achieving bright and biocompatible NIR quantum dots for multiplexed biodetection applications.

关键词： quantum dots cadmium-free aqueous synthesis photoluminescence imaging

EASE-DGGS:a hybrid discrete global grid system for Earth sciences

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Big Earth Data 2022年第3期6卷 340-357页

作者： j.ffery A.Thompson Mary j.Brodzik kevin A.T.Silverstein Mason A.Hurley Nathan L.Carlson Minnesota Supercomputing Institute University of MinnesotaMinneapolisMNUSA GEMS Informatics Initiative University of MinnesotaMinneapolisMNUSA National Snow and Ice Data Center Cooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderCOUSA

Although we live in an era of unprecedented quantities and access to data,deriving actionable information from raw data is a hard *** observation systems(EOS)have experienced rapid growth and uptake in recent decades,and the rate at which we obtain remotely sensed images is *** significant effort and attention has been devoted to designing systems that deliver analytics ready imagery faster,less attention has been devoted to developing analytical frameworks that enable EOS to be seamlessly integrated with other data for quantitative *** global grid systems(DGGS)have been proposed as one potential solution that addresses the challenge of geospatial data integration and ***,we propose the systematic extension of EASE-Grid in order to provide DGGS-like characteristics for EOS data *** describe the extensions as well as present implementation as an application programming interface(API),which forms part of the University of Minnesota’s GEMS(Genetic x Environment x Management x Socioeconomic)Informatics Center’s API portfolio.

关键词： Discrete global grid systems DGGS EASE Grid coordinate reference systems

Introduction to probability with Mathematica 2nd ed

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Discrete element modelling of the quasi-static uniaxial compression of individual infant formula agglomerates

2010年

作者： Hastings, kevin j.,

来源：畅想之星图书光盘版（南... 评论

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Particuology 2012年第5期10卷 523-531页

作者： kevin j.Hanley Catherine O'Sullivan Edmond P.Byrne kevin Cronin Department of Process and Chemical Engineering University College CorkCorkIreland Department of Civil and Environmental Engineering Skempton BuildingImperial College LondonLondon SW7 2AZ United Kingdom

Infant formula is usually produced in an agglomerated powder form. These agglomerates are subj.cted to many transient forces following their manufacture. These can be difficult to quantify experimentally because of their small magnitudes and short durations, Numerical models have the potential to address this gap in the experimental data. The obj.ctive of the research described here was to calibrate a discrete element model for these agglomerates using experimental data obtained for quasi-static loading, and to use this model to study the mechanics of the particle response in detail. The Taguchi method was previously proposed as a viable calibration approach for discrete element models. In this work, the method was assessed for calibration of the model parameters （e.g., bond stiffnesses and strengths） considering three responses： the force at failure, strain at failure and agglomerate stiffness. The Weibull moduli for the simulation results and the experimental data were almost identical following calibration and the 37% characteristic stresses were similar. An analysis of the energy terms in the model provided useful insight into the model response. The bond energy and the normal force exerted on the platens were strongly correlated, and bond breakage events coincided with the highest energy dissipation rates.

关键词： Discrete element modellingUniaxial compressionQuasi-static crushingSimulationGranular materialsTaguchi methods

The clinical impact of tricuspid regurgitation in patients with a biatrial orthotopic heart transplant

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Frontiers of Medicine 2023年第3期17卷 527-533页

作者： kevin M.Veen Grigorios Papageorgiou Casper F.Zij.erhand Mostafa M.Mokhles j.sper j.Brugts Olivier C.Manintveld Alina A.Constantinescu j.s A.Bekkers j.hanna j.Makkenberg Ad j.j.CBogers Kadir Caliskan Department of Cardiothoracic Surgery Erasmus MC3000 CA RotterdamThe Netherlands Department of Biostatistics Erasmus MC3000 CA RotterdamThe Netherlands Department of Cardiology Erasmus MC3000 CA RotterdamThe Netherlands

In this study,we aim to elucidate the clinical impact and long-term course of tricuspid regurgitation(TR),taking into account its dynamic nature,after biatrial orthotopic heart transplant(OHT).All consecutive adult patients undergoing biatrial OHT(1984−2017)with an available follow-up echocardiogram were ***-models were used to model the evolution of *** mixed-model was inserted into a Cox model in order to address the association of the dynamic TR with *** total,572 patients were included(median age:50 years,males:74.9%).Approximately 32% of patients had moderate-to-severe TR immediately after ***,this declined to 11%on 5 years and 9% on 10 years after surgery,adj.sted for survival *** mechanical support was associated with less TR during follow-up,whereas concurrent LV dysfunction was significantly associated with more TR during *** at 1,5,10,20 years was 97%±1%,88%±1%,66%±2% and 23%±2%,*** presence of moderate-to-severe TR during follow-up was associated with higher mortality(HR:1.07,95%CI(1.02–1.12),p=0.006).The course of TR was positively correlated with the course of creatinine(R=0.45).TR during follow-up is significantly associated with higher mortality and worse renal ***,probability of TR is the highest immediately after OHT and decreases ***,it may be reasonable to refrain from surgical intervention for TR during earlier phase after OHT.

关键词： orthotopic heart transplant tricuspid regurgitation clinical impact biatrial heart transplantation

RESEARCH PROGRESS ON THE IMPACT OF NITROGEN DEPOSITION ON GLOBAL GRASSLANDS

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Frontiers of Agricultural Science and Engineering 2022年第3期9卷 425-444页

作者： Carly j.STEVENS Sofía BASTO Michael DBELL Tianxiang HAO kevin KIRKMAN Raul OCHOA-HUESO Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUK Unidad de Ecologia y Sistematica Departamento de BiologiaFacultad de CienciasPontificia Universidad JaverianaCarrera 7 No.43-82 Ed.Jesus Emilio Ramirez(53)BogotaColombia National Park Service Air Resources DivisionLakewoodCO 80235USA Synthesis Research Center of Chinese Ecosystem Research Network Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant-Soil Interactions of Ministry of EducationBeijing Key Laboratory of Farmland Soil Pollution Prevention and RemediationChina Agricultural UniversityBeijing 100193China School of Life Sciences University of KwaZulu-NatalDurban4041South Africa Departamento de Biologia-IVAGRO Universidad de CadizCampus Rio San Pedro11510 Puerto RealSpain Department of Terrestrial Ecology Netherlands Institute of Ecology(NIOO-KNAW)P.O.Box 506700 ABWageningenthe Netherlands

Grasslands are globally-important ecosystems providing critical ecosystem *** species composition and characteristics of grasslands vary considerably across the planet with a wide variety of different grasslands ***,in many regions grasslands have been impacted by atmospheric nitrogen deposition originating from anthropogenic activities with effects on productivity,species composition and diversity widely *** vary across grassland habitats but many show declines in species richness and increases in biomass production related to soil eutrophication and *** a continental level,there is considerable variation in the research effort that has been put into understanding the impacts of nitrogen *** Europe,North America and parts of Asia,although there are unanswered research questions,there is a good understanding of N deposition impacts in most grassland *** is not the case in other regions with large knowledge gaps in some parts of the *** paper reviews the impacts of N deposition on grasslands around the world,highlighting recent advances and areas where research is still needed.

关键词： acidification biomass production critical load eutrophication species composition species richness