8,059 research outputs found
Proteger los datos personales sobre la salud es un derecho. Redimensionar su importancia, una necesidad
Lifting properties in operator ranges
Given a bounded positive linear operator A on a Hilbert space H we consider the semi-Hilbertian space (H, _A), where _A =. On the other hand, we consider the operator range R(A^1/2) with its canonical Hilbertian structure, denoted by R(A^1/2). In this paper we explore the relationship between different types of operators on (H, _A) with classical subsets of operators on R(A^1/2), like Hermitian, normal, contractions, projections, partial isometries and so on. We extend a theorem by M. G. Krein on symmetrizable operators and a result by M. Mbekhta on reduced minimum modulus.Fil: Arias, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; ArgentinaFil: Corach, Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; ArgentinaFil: Gonzalez, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; Argentin
B (page as dance stage)
Printed work in Crux Desperationis, issue 5 (PDF 3.7MB), Montevideo, January 2014, p. 12
Don't say anything
Laura Gonzalez will return to Frau Emmy von N. the words Sigmund Freud wrote in his famous case history about her. She will tell you her story of hysteria in the first person, just as Emmy would have told it to Freud in 1889
Supertranslations and Superrotations at the Black Hole Horizon
We show that the asymptotic symmetries close to nonextremal black hole
horizons are generated by an extension of supertranslations. This group is
generated by a semidirect sum of Virasoro and Abelian currents. The charges
associated with the asymptotic Killing symmetries satisfy the same algebra.
When considering the special case of a stationary black hole, the zero mode
charges correspond to the angular momentum and the entropy at the horizon.Comment: 6 pages, references added, published versio
Heterogeneous and rate-dependent streptavidin-biotin unbinding revealed by high-speed force spectroscopy and atomistic simulations
Receptor-ligand interactions are essential for biological function and their
binding strength is commonly explained in terms of static lock-and-key models
based on molecular complementarity. However, detailed information of the full
unbinding pathway is often lacking due, in part, to the static nature of atomic
structures and ensemble averaging inherent to bulk biophysics approaches. Here
we combine molecular dynamics and high-speed force spectroscopy on the
streptavidin-biotin complex to determine the binding strength and unbinding
pathways over the widest dynamic range. Experiment and simulation show
excellent agreement at overlapping velocities and provided evidence of the
unbinding mechanisms. During unbinding, biotin crosses multiple energy barriers
and visits various intermediate states far from the binding pocket while
streptavidin undergoes transient induced fits, all varying with loading rate.
This multistate process slows down the transition to the unbound state and
favors rebinding, thus explaining the long lifetime of the complex. We provide
an atomistic, dynamic picture of the unbinding process, replacing a simple
two-state picture with one that involves many routes to the lock and
rate-dependent induced-fit motions for intermediates, which might be relevant
for other receptor-ligand bonds.Comment: 21 pages, 4 figure
Guidance of trunk neural crest migration requires neuropilin 2/semaphorin 3F signaling
In vertebrate embryos, neural crest cells migrate only through the anterior half of each somite while avoiding the posterior half. We demonstrate that neural crest cells express the receptor neuropilin 2 (Npn2), while its repulsive ligand semaphorin 3F (Sema3f) is restricted to the posterior-half somite. In Npn2 and Sema3f mutant mice, neural crest cells lose their segmental migration pattern and instead migrate as a uniform sheet, although somite polarity itself remains unchanged. Furthermore, Npn2 is cell autonomously required for neural crest cells to avoid Sema3f in vitro. These data show that Npn2/Sema3f signaling guides neural crest migration through the somite. Interestingly, neural crest cells still condense into segmentally arranged dorsal root ganglia in Npn2 nulls, suggesting that segmental neural crest migration and segmentation of the peripheral nervous system are separable processes
Virtual worlds: visualizing early modern festivals in the Iberian world
This article explores the potential and limits Virtual Heritage Visualization techniques pose for historical/urban/architectural research. It discusses its aplication to the study of historic urban environments and early modern festivals in the Iberian world
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