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Displacement Current in Domain Walls of Bismuth Ferrite

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npj Computational Materials 2018年第1期4卷 597-605页

作者： Sergey Prosandeev Yurong Yang charles Paillard l.Bellaiche Physics Department and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA Institute of Physics and Physics Department of Southern Federal UniversityRostov-na-Donu 344090Russia

In 1861,Maxwell conceived the idea of the displacement current,which then made laws of electrodynamics more complete and also resulted in the realization of devices exploiting such displacement ***,it is presently unknown if such displacement current can result in large intrinsic ac current in ferroic systems possessing domains,despite the flurry of recent activities that have been devoted to domains and their corresponding conductivity in these ***,we report firstprinciples-based atomistic simulations that predict that the transverse(polarization-related)displacement currents of 71°and 109°domains in the prototypical BiFeO_(3) multiferroic material are significant at the walls of such domains and in the GHz regime,and,in fact,result in currents that are at least of the same order of magnitude than previously reported dc currents(that are likely extrinsic in nature and due to electrons).Such large,localized and intrinsic ac currents are found to originate from low-frequency vibrations at the domain walls,and may open the door to the design of novel devices functioning in the GHz or THz range and in which currents would be confined within the domain wall.

关键词： currents regime magnitude

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

Contemporary Approaches for Identifying Rare Bone Disease Causing Genes

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Bone Research 2013年第4期1卷 301-310页

作者： charles R.Farber Thomas l.Clemens Center for Public Health Genomics University of Virginia Departments of Public Health Sciences and Biochemistry and Molecular Genetics University of Virginia Department of Orthopaedic Surgery Johns Hopkins School of Medicine Baltimore Veterans Administration Medical Center

Recent improvements in the speed and accuracy of DNA sequencing, together with increasingly sophisti- cated mathematical approaches for annotating gene networks, have revolutionized the field of human genetics and made these once time consuming approaches assessable to most investigators. In the field of bone research, a particularly active area of gene discovery has occurred in patients with rare bone disorders such as osteogenesis imperfecta （OI） that are caused by mutations in single genes. In this perspective, we highlight some of these technological advances and describe how they have been used to identify the genetic determinants underlying two previously unexplained cases of OI. The widespread availability of advanced methods for DNA sequencing and bioinformatics analysis can be expected to greatly facilitate identification of novel gene networks that normally function to control bone formation and maintenance.

关键词： exome sequencing genome sequencing bioinformatics osteogenesis imperfect pigment epithelium-derived factor (PEDF) bone restricted ifitm-like protein (Bril)

Strain control of layer-resolved negative capacitance in superlattices

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npj Computational Materials 2020年第1期6卷 127-130页

作者： Raymond Walter Sergey Prosandeev charles Paillard l.Bellaiche Department of Physics and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA Department of Mathematical Sciences University of ArkansasFayettevilleAR 72701USA Identity Engineering Kinesso LLCConwayAR 72032USA Institute of Physics and Physics Department of Southern Federal University Rostov-na-Donu 344090Russia laboratoire Structures Propriétés et Modélisation des SolidesCentraleSupélecUMR CNRS 8580UniversitéParis-Saclay91190 Gif-sur-YvetteFrance

Negative capacitance in BaTiO_(3)/SrTiO_(3) superlattices is investigated by Monte Carlo simulations in an atomistic effective Hamiltonian model,using fluctuation formulas for responses to the local macroscopic field that incorporates depolarizing *** show that epitaxial strain can tune the negative capacitance of the BaTiO_(3) ferroelectric layer and the overall capacitance of the *** addition,we predict and explain an original switching of the negative capacitance from the BaTiO3 layer to the SrTiO_(3) layer at low temperatures for intermediate strains.

关键词： capacitance layer resolved

Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

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Energy & Environmental Materials 2024年第1期7卷 229-237页

作者： Veniero lenzi José P.B.Silva Břetislav Šmíd Vladimir Matoín Cosmin M.Istrate Corneliu Ghica Judith l.MacManus-Driscoll luís Marques Physics Center of Minho and Porto Universities(CF-UM-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of Materials Physics 105 bis Atomistilor 077125Magurele Romania Department of Materials Science and Metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

Mannose-binding lectin and maladies of the bowel and liver

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World Journal of Gastroenterology 2006年第40期12卷 6420-6428页

作者： Daniel l Worthley Peter G Bardy David l Gordon charles G Mullighan Department of Gastroenterology and Hepatology Flinders Medical Centre South Australia Australia Division of Haematology Royal Adelaide Hospital and Institute of Medical and Veterinary Science South Australia Australia Department of Haematology-Oncology The Queen Elizabeth Hospital South Australia Australia Department of Microbiology and Infectious Diseases Flinders Medical Centre South Australia Australia Division of Haematology Royal Adelaide Hospital and Institute of Medical and Veterinary Science South Australia Australia Pathology St. Jude Children’s Research Hospital Memphis Tennessee United States

Mannose-binding lectin (MBl) is a pattern-recognition molecule that binds to characteristic carbohydrate mo-tifs present on the surface of many different pathogens. MBl binding stimulates the immune system via the lectin pathway of complement activation. In certain clinical situations, often characterized by pre-existing immune compromise, MBl deficiency increases the risk of infec-tious and other disease-specific complications. Many of the key pathogenic processes inherent to common gastroenterological diseases, such as infection, immuno-logical damage, and carcinogenesis, have been linked to MBl. This editorial reviews the biology of MBl, outlines key disease associations to document the breadth of influence of MBl, and finally, highlights the relevance of MBl to both gastroenterological health and disease.

关键词： Mannose-binding lectin Collectins, Innate immunity Polymorphism Infection

Post-transcriptional regulation of vascular endothelial growth factor: Implications for tumor angiogenesis

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World Journal of Gastroenterology 2006年第31期12卷 4937-4942页

作者： Peter S Yoo Abby l Mulkeen charles H Cha Gastrointestinal Surgery and Surgical OncologyYale School of Medicine New HavenConnecticutUnited States

Vascular endothelial growth factor （VEGF） is a potent secreted mitogen critical for physiologic and tumor angiogenesis. Regulation of VEGF occurs at several levels, including transcription, mRNA stabilization, translation, and differential cellular localization of various isoforms. Recent advances in our understanding of post-transcriptional regulation of VEGF include identification of the stabilizing mRNA binding protein, HuR, and the discovery of internal ribosomal entry sites in the 5＇UTR of the VEGF mRNA. Monoclonal anti-VEGF antibody was recently approved for use in humans, but suffers from the need for high systemic doses. RNA interference （RNAi） technology is being used in vitro and in animal models with promising results. Here, we review the literature on post-transcriptional regulation of VEGF and describe recent progress in targeting these mechanisms for therapeutic benefit.

关键词： Vascular endothelial growth factor Vascular endothelial growth hormone Post-transcriptional regulation mRNA stability HuR ElAVl Internal ribosomal entry IRES siRNA RNAi Bevacizumab

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.lukáˇc D.Koutný J.Jaroš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SlM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SlM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SlM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M NaCl solution was superior to the SlM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SlM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

Targeted therapy for capillary-venous malformations

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Signal Transduction and Targeted Therapy 2024年第7期9卷 3024-3039页

作者： lola Zerbib Sophia ladraa Antoine Fraissenon charles Bayard Marina Firpion Quitterie Venot Sanela Protic Clément Hoguin Amandine Thomas Sylvie Fraitag Jean-Paul Duong Sophie Kaltenbach Estelle Balducci Coline lefevre Patrick Villarese Vahid Asnafi Christine Broissand Nicolas Goudin Ivan Nemazanyy Gwennhael Autret Bertrand Tavitian Christophe legendre Nadia Arzouk Veronique Minard-Colin Caroline Chopinet Michael Dussiot Denise MAdams Tristan Mirault laurent Guibaud Paul Isenring Guillaume Canaud UniversitéParis Cité ParisFrance INSERM U1151 Institut Necker-Enfants MaladesParisFrance Service d’Imagerie Pédiatrique Hôpital Femme-Mère-EnfantHCLBronFrance CREATIS UMR 5220 Villeurbanne 69100France Service de Radiologie Mère-Enfant Hôpital NordSaint EtienneFrance Service d’Anatomie pathologique Hôpital Necker-Enfants MaladesAP-HPParisFrance laboratoire d’Oncohématologie Hôpital Necker-Enfants MaladesAP-HPParisFrance Pharmacie Hôpital Necker-Enfants MaladesAP-HPParisFrance Necker Bio-Image Analysis INSERM US24/CNRS UMS 3633ParisFrance Platform for Metabolic Analyses Structure Fédérative de Recherche NeckerINSERM US24/CNRS UMS 3633ParisFrance Plateforme Imageries du Vivant Universitéde ParisPARCCINSERMParisFrance Service de Néphrologie Transplantation AdultesHôpital Necker-Enfants MaladesAP-HPParisFrance Service de Transplantation Hôpital La PitiéSalpétrièreAP-HPParisFrance Department of Pediatric and Adolescent Oncology INSERM 1015Gustave RoussyUniversitéParis-SaclayVillejuifFrance Service de Physiologie&Explorations Fonctionnelles Cardiovasculaires CHU de LilleLille 59000France INSERM U1163 Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic ImplicationsLaboratoire d’Excellence GR-ExParisFrance Division of Oncology Comprehensive Vascular Anomalies ProgramChildren’s Hospital of PhiladelphiaPhiladelphiaPAUSA Service de Médecine Vasculaire hôpital Européen Georges-PompidouParisFrance Nephrology Research Group L’Hôtel-Dieu de Québec Research CenterDepartment of MedicineFaculty of MedicineLaval UniversityQuebecQC G1R2J6Canada Unitéde médecine translationnelle et thérapies ciblées Hôpital Necker-Enfants MaladesAP-HPParisFrance CNRS UMR8253 Institut Necker-Enfants MaladesParisFrance

Sporadic venous malformations are genetic conditions primarily caused by somatic gain-of-function mutation of PIK3CA or TEK,an endothelial transmembrane receptor signaling through *** malformations are associated with pain,bleedings,thrombosis,pulmonary embolism,esthetic deformities and,in severe cases,life-threatening *** authorized medical treatment exists for patients with venous ***,we created a genetic mouse model of PIK3CA-related capillary venous malformations that replicates patient *** showed that these malformations only partially signal through AKT *** compared the efficacy of different drugs,including rapamycin,a mTORC1 inhibitor,miransertib,an AKT inhibitor and alpelisib,a PI3Kαinhibitor at improving the lesions seen in the mouse *** demonstrated the effectiveness of alpelisib in preventing vascular malformations’occurrence,improving the already established ones,and prolonging *** these findings,we were authorized to treat 25 patients with alpelisib,including 7 children displaying PIK3CA(n=16)or TEK(n=9)-related capillary venous malformations resistant to usual therapies including sirolimus,debulking surgical procedures or percutaneous *** assessed the volume of vascular malformations using magnetic resonance imaging(MRI)for each *** demonstrated improvement in all 25 *** malformations previously considered intractable were reduced and clinical symptoms were *** showed a decrease of 33.4%and 27.8%in the median volume of PIK3CA and TEK malformations respectively,over 6 months on *** conclusion,this study supports PI3Kαinhibition as a promising therapeutic strategy in patients with PIK3CA or TEK-related capillary venous malformations.

关键词： PIK3CA malformations venous