scispace - formally typeset
Search or ask a question
Institution

University of Virginia

EducationCharlottesville, Virginia, United States
About: University of Virginia is a education organization based out in Charlottesville, Virginia, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 52543 authors who have published 113268 publications receiving 5220506 citations. The organization is also known as: U of V & UVa.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, the authors explore how the introduction of habit preferences into the simple intertemporal consumption-based capital asset pricing model "solves" the equity premium and risk-free rate puzzles.

1,030 citations

Journal ArticleDOI
TL;DR: The findings support a model for FPD/AML in which haploinsufficiency of CBFA2 causes an autosomal dominant congenital platelet defect and predisposes to the acquisition of additional mutations that cause leukaemia.
Abstract: Familial platelet disorder with predisposition to acute myelogenous leukaemia (FPD/AML, MIM 601399) is an autosomal dominant disorder characterized by qualitative and quantitative platelet defects, and propensity to develop acute myelogenous leukaemia (AML). Informative recombination events in 6 FPD/AML pedigrees with evidence of linkage to markers on chromosome 21q identified an 880-kb interval containing the disease gene. Mutational analysis of regional candidate genes showed nonsense mutations or intragenic deletion of one allele of the haematopoietic transcription factor CBFA2 (formerly AML1) that co-segregated with the disease in four FPD/AML pedigrees. We identified heterozygous CBFA2 missense mutations that co-segregated with the disease in the remaining two FPD/AML pedigrees at phylogenetically conserved amino acids R166 and R201, respectively. Analysis of bone marrow or peripheral blood cells from affected FPD/AML individuals showed a decrement in megakaryocyte colony formation, demonstrating that CBFA2 dosage affects megakaryopoiesis. Our findings support a model for FPD/AML in which haploinsufficiency of CBFA2 causes an autosomal dominant congenital platelet defect and predisposes to the acquisition of additional mutations that cause leukaemia.

1,028 citations

Book
19 Mar 2001
TL;DR: In this article, the authors considered the properties of orthogonal polynomials on the unit sphere, root systems and Coxeter groups, and the Summability of Orthogonal expansions.
Abstract: Preface to the second edition Preface to the first edition 1. Background 2. Orthogonal polynomials in two variables 3. General properties of orthogonal polynomials in several variables 4. Orthogonal polynomials on the unit sphere 5. Examples of orthogonal polynomials in several variables 6. Root systems and Coxeter groups 7. Spherical harmonics associated with reflection groups 8. Generalized classical orthogonal polynomials 9. Summability of orthogonal expansions 10. Orthogonal polynomials associated with symmetric groups 11. Orthogonal polynomials associated with octahedral groups and applications References Author index Symbol index Subject index.

1,026 citations

Journal ArticleDOI
19 Jul 2012-Nature
TL;DR: The observation of an insulator–metal transition in vanadium dioxide induced by a terahertz electric field is reported, demonstrating that integration of metamaterials with complex matter is a viable pathway to realize functional nonlinear electromagnetic composites.
Abstract: An innovative technique uses ultrafast below-bandgap electric-field pulses to induce and probe an insulator–metal transition in an oxide thin film on which a metamaterial structure has been deposited. The transition from insulating to metallic behaviour and the microscopic interactions that accompany the transition are important phenomena in electronic materials. Until now it has not been possible to observe the transition directly in a time-resolved manner. Here, Richard Averitt and colleagues use ultrafast terahertz pulses to induce a phase transition in a prototypical insulator–metal transition material (vanadium dioxide) on which a metamaterial structure has been deposited. The metamaterial serves to amplify the local terahertz field, as well as to detect macroscopic changes in vanadium dioxide. Through direct, time-resolved observations, the authors establish a detailed microscopic picture of the structural and electronic changes underlying the insulator–metal transition. They conclude that their technique is versatile and could even be used to study phase transitions in superconductors. Electron–electron interactions can render an otherwise conducting material insulating1, with the insulator–metal phase transition in correlated-electron materials being the canonical macroscopic manifestation of the competition between charge-carrier itinerancy and localization. The transition can arise from underlying microscopic interactions among the charge, lattice, orbital and spin degrees of freedom, the complexity of which leads to multiple phase-transition pathways. For example, in many transition metal oxides, the insulator–metal transition has been achieved with external stimuli, including temperature, light, electric field, mechanical strain or magnetic field2,3,4,5,6,7. Vanadium dioxide is particularly intriguing because both the lattice and on-site Coulomb repulsion contribute to the insulator-to-metal transition at 340 K (ref. 8). Thus, although the precise microscopic origin of the phase transition remains elusive, vanadium dioxide serves as a testbed for correlated-electron phase-transition dynamics. Here we report the observation of an insulator–metal transition in vanadium dioxide induced by a terahertz electric field. This is achieved using metamaterial-enhanced picosecond, high-field terahertz pulses to reduce the Coulomb-induced potential barrier for carrier transport9. A nonlinear metamaterial response is observed through the phase transition, demonstrating that high-field terahertz pulses provide alternative pathways to induce collective electronic and structural rearrangements. The metamaterial resonators play a dual role, providing sub-wavelength field enhancement that locally drives the nonlinear response, and global sensitivity to the local changes, thereby enabling macroscopic observation of the dynamics10,11. This methodology provides a powerful platform to investigate low-energy dynamics in condensed matter and, further, demonstrates that integration of metamaterials with complex matter is a viable pathway to realize functional nonlinear electromagnetic composites.

1,023 citations

Journal ArticleDOI
TL;DR: The authors argued that exposure to such supports is predictive of greater student learning gains and that teachers' behavioral interactions with students can be assessed observationally using standardized protocols, analyzed systematically with regard to sources of error, validated for predicting student learning, and changed (improved) as a function of specific and aligned supports provided to teachers.
Abstract: The authors advance an argument that placing observation of actual teaching as a central feature of accountability frameworks, teacher preparation, and basic science could result in substantial improvements in instruction and related social processes and a science of the production of teaching and teachers. Teachers’ behavioral interactions with students can be (a) assessed observationally using standardized protocols, (b) analyzed systematically with regard to sources of error, (c) validated for predicting student learning, and (d) changed (improved) as a function of specific and aligned supports provided to teachers; exposure to such supports is predictive of greater student learning gains. These methods have considerable promise; along with measurement challenges, some of which pertain to psychometrics, efficiency, and costs, they merit attention, rigorous study, and substantial research investments.

1,021 citations


Authors

Showing all 53083 results

NameH-indexPapersCitations
Joan Massagué189408149951
Michael Rutter188676151592
Gordon B. Mills1871273186451
Ralph Weissleder1841160142508
Gonçalo R. Abecasis179595230323
Jie Zhang1784857221720
John R. Yates1771036129029
John A. Rogers1771341127390
Bradley Cox1692150156200
Mika Kivimäki1661515141468
Hongfang Liu1662356156290
Carl W. Cotman165809105323
Ralph A. DeFronzo160759132993
Elio Riboli1581136110499
Dan R. Littman157426107164
Network Information
Related Institutions (5)
Columbia University
224K papers, 12.8M citations

96% related

University of Pennsylvania
257.6K papers, 14.1M citations

96% related

University of Michigan
342.3K papers, 17.6M citations

96% related

University of Washington
305.5K papers, 17.7M citations

96% related

Stanford University
320.3K papers, 21.8M citations

96% related

Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023189
2022783
20215,565
20205,600
20195,001
20184,586