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journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee r.K.Singh raman Derrek E.Lobo Christopher D.Easton Mainak Majumder Frank Witte jörg F.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIrO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia julius Wolff Institute and Berlin Brandenburg Center for regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(rGO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

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Lax-Oleinik-Type Formulas and Efficient Algorithms for Certain High-Dimensional Optimal Control Problems

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1428-1471页

作者： Paula Chen jerome Darbon Tingwei Meng Division of Applied Mathematics Brown UniversityProvidenceRIUSA Department of Mathematics UCLALos AngelesCAUSA

Two of the main challenges in optimal control are solving problems with state-dependent running costs and developing efficient numerical solvers that are computationally tractable in high *** this paper,we provide analytical solutions to certain optimal control problems whose running cost depends on the state variable and with constraints on the *** also provide Lax-Oleinik-type representation formulas for the corresponding Hamilton-jacobi partial differential equations with state-dependent ***,we present an efficient,grid-free numerical solver based on our representation formulas,which is shown to scale linearly with the state dimension,and thus,to overcome the curse of *** existing optimization methods and the min-plus technique,we extend our numerical solvers to address more general classes of convex and nonconvex initial *** demonstrate the capabilities of our numerical solvers using implementations on a central processing unit(CPU)and a field-programmable gate array(FPGA).In several cases,our FPGA implementation obtains over a 10 times speedup compared to the CPU,which demonstrates the promising performance boosts FPGAs can *** numerical results show that our solvers have the potential to serve as a building block for solving broader classes of high-dimensional optimal control problems in real-time.

关键词： Optimal control Hamilton-jacobi partial differential equations Grid-free numerical methods High dimensions Field-programmable gate arrays(FPGAs)

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

关键词：

Global weirding at mass extinction horizons

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National Science review 2024年第1期11卷 10-12页

作者： Gregory j.retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Solid-liquid extraction for yttrium recovery using porous polymeric resin(XAD-7) functionalized with D_(2)EHPA

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journal of rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： P.A.Martínez-Montoya r.G.Sanchez-Alvarado D.Y.Medina-Velazquez M.L.Carrera-jota P.Garnica-Chávez A.de j.Morales-ramirez Higher School of Chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico Metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for research and Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Yttrium recovery rare earth solid-liquid extraction XAD-7 resin Fluorescent lamps recycling Solid-liquid kinetics extraction

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Temporal trends and practice variation of paediatric diagnostic tests in primary care:retrospective analysis of 14 million tests

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Family Medicine and Community Health 2024年第4期12卷 1-8页

作者： Elizabeth T Thomas Diana r Withrow Cynthia Wright Drakesmith Peter j Gill rafael Perera-Salazar Carl Heneghan Centre for Evidence-Based Medicine Nuffield Department of Primary Care Health SciencesUniversity of OxfordOxfordUK Nuffield Department of Primary Care Health Sciences University of OxfordOxfordUK Department of Pediatrics University of TorontoTorontoOntarioCanada Hospital for Sick Children TorontoOntarioCanada

Objective The primary objective was to investigate temporal trends and between-practice variability of paediatric test use in primary *** and analysis This was a descriptive study of population-based data from Clinical Practice research Datalink Aurum primary care consultation records from 1 january 2007 to 31 December *** aged 0–15 who were registered to one of the eligible 1464 general practices and had a diagnostic test code in their clinical record were *** primary outcome measures were(1)temporal changes in test rates measured by the average annual percent change,stratified by test type,gender,age group and deprivation level and(2)practice variability in test use,measured by the coefficient of *** 14299598 diagnostic tests were requested over 27.8 million child-years of observation for 2542101 *** test use increased by 3.6%/year(95%CI 3.4 to 3.8%)from 399/1000 child-years to 608/1000 child-years,driven by increases in blood tests(8.0%/year,95%CI 7.7 to 8.4),females aged 11–15(4.0%/year,95%CI 3.7 to 4.3),and children from the most socioeconomically deprived group(4.4%/year,95%CI 4.1 to 4.8).Tests subject to the greatest temporal increases were faecal calprotectin,fractional exhaled nitric oxide and vitamin *** classified as high-use and high-practice variability were iron studies,coeliac testing,vitamin B12,folate,and vitamin *** In this first nationwide study of paediatric test use in primary care,we observed significant temporal increases and practice variability in *** reflects inconsistency in practice and diagnosis rates and a scarcity of evidence-based *** test use generates more clinical activity with significant resource implications but conversely may improve clinical *** research should evaluate whether increased test use and variability are warranted by exploring test indications and test results and directly examine how increased test use impacts

关键词： vitamin nationwide stratified

Metabolic reprogramming by Syntenin-1 directs rA FLS and endothelial cell-mediated inflammation and angiogenesis

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Cellular & Molecular Immunology 2024年第1期21卷 33-46页

作者： Anja Meyer Stephanie r.Zack Wes Nijim Adel Burgos Vishwa Patel Brian Zanotti Michael V.Volin M.Asif Amin Myles j.Lewis Costantino Pitzalis Shiva Arami joseph A.Karam Nadera j.Sweiss Shiva Shahrara jesse Brown VA Medical Center ChicagoILUSA Department of Medicine Division of RheumatologyThe University of Illinois at ChicagoChicagoILUSA Department of Microbiology and Immunology Midwestern UniversityDowners GroveILUSA Division of rheumatology and Clinical Autoimmunity Center of Excellence University of MichiganAnn ArborMIUSA Centre for Experimental Medicine and rheumatology William Harvey Research InstituteBarts and The London School of Medicine and DentistryQueen Mary University of LondonLondonUnited Kingdom Centre for Experimental Medicine&rheumatology William Harvey Research InstituteQueen Mary University of London and Barts NIHR BRC&NHS TrustLondonUK Department of Biomedical Sciences Humanitas Universityand Humanitas Research HospitalMilanItaly Department of Orthopedic Surgery the University of Illinois at ChicagoChicagoILUSA

A novel rheumatoid arthritis(rA)synovial fluid protein,Syntenin-1,and its receptor,Syndecan-1(SDC-1),are colocalized on rA synovial tissue endothelial cells and fibroblast-like synoviocytes(FLS).Syntenin-1 exacerbates the inflammatory landscape of endothelial cells and rA FLS by upregulating transcription of IrF1/5/7/9,IL-1β,IL-6,and CCL2 through SDC-1 ligation and HIF1α,or mTOr ***,Syntenin-1 orchestrates rA FLS and endothelial cell invasion via SDC-1 and/or mTOr *** Syntenin-1 reprogrammed endothelial cells,the dynamic expression of metabolic intermediates coincides with escalated glycolysis along with unchanged oxidative factors,AMPK,PGC-1α,citrate,and inactive oxidative ***,rA FLS rewired by Syntenin-1 displayed a modest glycolytic-ATP accompanied by a robust mitochondrial-ATP *** enriched mitochondrial-ATP detected in Syntenin-1 reprogrammed rA FLS was coupled with mitochondrial fusion and fission recapitulated by escalated Mitofusin-2 and DrP1 *** found that VEGFr1/2 and Notch1 networks are responsible for the crosstalk between Syntenin-1 rewired endothelial cells and rA FLS,which are also represented in rA *** to rA explants,morphological and transcriptome studies authenticated the importance of VEGFr1/2,Notch1,rAPTOr,and HIF1αpathways in Syntenin-1 arthritic mice and their obstruction in SDC-1 deficient ***,dysregulation of SDC-1,mTOr,and HIF1αnegated Syntenin-1 inflammatory phenotype in rA explants,while inhibition of HIF1αimpaired synovial angiogenic imprint amplified by *** conclusion,since the current therapies are ineffective on Syntenin-1 and SDC-1 expression in rA synovial tissue and blood,targeting this pathway and its interconnected metabolic intermediates may provide a novel therapeutic strategy.

关键词： Syntenin-1 Syndecan-1 rA FLS rA explants immunometabolism

BaTiO3 solid solutions co-doped with Gd3+ and Eu3+:Synthesis,structural evolution and dielectric properties

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journal of rare Earths 2024年第10期42卷 1920-1926页

作者： r.Martínez-López M.Pérez-Labra j.A.romero-Serrano F.r.Barrientos-Hernández M.reyes-Pérez M.I.Valenzuela-Carrillo G.Urbano-reyes V.E.reyes-Cruz G.I.Dávila-Pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo State Metallurgy and Materials Department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XrD） and rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO3 Doping Europium Gadolinium rare earths Synthesis

Decoding the genetic program of micronucleus formation: linking chromosomal instability to human disease

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2840-2842页

作者： jörg Fahrer Division of Food Chemistry and Toxicology Department of ChemistryRPTU Kaiserslautern-Landau67663 KaiserslauternGermany

A recent study by Adams and colleagues published in Nature unveiled more than one hundred genes that are involved in micronucleus formation,1 which is a biomarker for genomic instability and associated with aging,cancer,and other disorders.2 As an outstanding achievement,the authors identified DSCC1(DNA replication And Sister Chromatid Cohesion 1)as a critical gene protecting against early developmental defects,genomic instability,reduced proliferative capacity,cohesinopathy-related phenotypes,and tumor development in vivo.

关键词： chromosomal linking replication

Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management