113 research outputs found
A novel K+ channel blocking toxin from Tityus discrepans scorpion venom
AbstractA novel toxin (TdK1) was purified from the venom of the scorpion Tityus discrepans, sequenced and functionally characterized. It contains 37 amino acid residues and blocks reversible the shakerB K+ channel expressed in SF9 cells with a Kd in the order of 280 nM. The proposed systematic nomenclature for this peptide is α-KTx4.3
Integrable open spin chains from giant gravitons
We prove that in the presence of a maximal giant graviton state in N=4 SYM,
the states dual to open strings attached to the giant graviton give rise to an
PSU(2,2|4) open spin chain model with integrable boundary conditions in the
SO(6) sector of the spin chain to one loop order.Comment: 18 pages, 2 figures, uses JHEP
Digital Fit: la influencia de las redes sociales en la alimentaciĂłn y en el aspecto fĂsico de los menores
Este proyecto se sitĂșa en el vĂ©rtice de tres ejes:
a) los influencers como destinatarios crecientes
de la atenciĂłn y la confianza de los menores online;
b) contenidos patrocinados generados por
estos influencers sobre hĂĄbitos alimenticios y
aspecto fĂsico, y c) la capacidad del menor para
identificar la intencionalidad persuasiva de estos
contenidos. El anĂĄlisis de la interacciĂłn de los
tres ejes radica en la incidencia del consumo de
estos contenidos en su autoestima y en la adopciĂłn
de hĂĄbitos que pueden impactar en su bienestar
personal. Se busca conocer el imaginario
alrededor de hĂĄbitos alimenticios, actividad fĂsica
e importancia del aspecto fĂsico, generado en
los menores por el discurso patrocinado de los
influencers. Se propone una metodologĂa mixta
deductiva que incluye la elaboraciĂłn de un cuestionario
dirigido a menores entre 11 y 17 años
(1.070 participantes) complementado con 12 focus
groups o grupos de discusiĂłn. Los resultados
serĂĄn relevantes para empresas que cuentan
con influencers en sus estrategias de marketing,
a las familias y educadores, y a las Administraciones
pĂșblicas
Two-body decays in the minimal 331 model
The two-body decays of the extra neutral boson Z_2 predicted by the minimal
331 model are analyzed. At the three-level it can decay into standard model
particles as well as exotic quarks and the new gauge bosons predicted by the
model. The decays into a lepton pair are strongly suppressed, with and . In the bosonic
sector, Z_2 would decay mainly into a pair of bilepton gauge bosons, with a
branching ratio below the 0.1 level. The Z_2 boson has thus a leptophobic and
bileptophobic nature and it would decay dominantly into quark pairs. The
anomaly-induced decays and , which occurs
at the one-loop level are studied. It is found that and at most. As for the and decays, with H a relatively light Higgs boson, they
are induced via Z'-Z mixing. It is obtained that
and . We also examine the flavor changing neutral
current decays and , which may have branching
fractions as large as and , respectively, and thus may be of
phenomenological interest.Comment: 14 pages, 3 figures, submitted to Physical Review
Interstellar MHD Turbulence and Star Formation
This chapter reviews the nature of turbulence in the Galactic interstellar
medium (ISM) and its connections to the star formation (SF) process. The ISM is
turbulent, magnetized, self-gravitating, and is subject to heating and cooling
processes that control its thermodynamic behavior. The turbulence in the warm
and hot ionized components of the ISM appears to be trans- or subsonic, and
thus to behave nearly incompressibly. However, the neutral warm and cold
components are highly compressible, as a consequence of both thermal
instability in the atomic gas and of moderately-to-strongly supersonic motions
in the roughly isothermal cold atomic and molecular components. Within this
context, we discuss: i) the production and statistical distribution of
turbulent density fluctuations in both isothermal and polytropic media; ii) the
nature of the clumps produced by thermal instability, noting that, contrary to
classical ideas, they in general accrete mass from their environment; iii) the
density-magnetic field correlation (or lack thereof) in turbulent density
fluctuations, as a consequence of the superposition of the different wave modes
in the turbulent flow; iv) the evolution of the mass-to-magnetic flux ratio
(MFR) in density fluctuations as they are built up by dynamic compressions; v)
the formation of cold, dense clouds aided by thermal instability; vi) the
expectation that star-forming molecular clouds are likely to be undergoing
global gravitational contraction, rather than being near equilibrium, and vii)
the regulation of the star formation rate (SFR) in such gravitationally
contracting clouds by stellar feedback which, rather than keeping the clouds
from collapsing, evaporates and diperses them while they collapse.Comment: 43 pages. Invited chapter for the book "Magnetic Fields in Diffuse
Media", edited by Elisabete de Gouveia dal Pino and Alex Lazarian. Revised as
per referee's recommendation
Transport coefficients and resonances for a meson gas in Chiral Perturbation Theory
We present recent results on a systematic method to calculate transport
coefficients for a meson gas (in particular, we analyze a pion gas) at low
temperatures in the context of Chiral Perturbation Theory (ChPT). Our method is
based on the study of Feynman diagrams taking into account collisions in the
plasma by means of the non-zero particle width. This implies a modification of
the standard ChPT power counting scheme. We discuss the importance of
unitarity, which allows for an accurate high energy description of scattering
amplitudes, generating dynamically the and mesons. Our
results are compatible with analyses of kinetic theory, both in the
non-relativistic very low- regime and near the transition. We show the
behavior with temperature of the electrical and thermal conductivities as well
as of the shear and bulk viscosities. We obtain that bulk viscosity is
negligible against shear viscosity, except near the chiral phase transition
where the conformal anomaly might induce larger bulk effects. Different
asymptotic limits for transport coefficients, large- scaling and some
applications to heavy-ion collisions are studied.Comment: Invited talk given at the international workshop Hot Quarks 2008,
Estes Park, Colorado, USA, August 18-23 2008. Accepted as a regular article
in Eur.Phys.J.C. 18 pages EPJC style, 23 figure
Evolution of the use of corticosteroids for the treatment of hospitalised COVID-19 patients in Spain between March and November 2020: SEMI-COVID national registry
Objectives: Since the results of the RECOVERY trial, WHO recommendations about the use of corticosteroids (CTs) in COVID-19 have changed. The aim of the study is to analyse the evolutive use of CTs in Spain during the pandemic to assess the potential influence of new recommendations. Material and methods: A retrospective, descriptive, and observational study was conducted on adults hospitalised due to COVID-19 in Spain who were included in the SEMI-COVID- 19 Registry from March to November 2020. Results: CTs were used in 6053 (36.21%) of the included patients. The patients were older (mean (SD)) (69.6 (14.6) vs. 66.0 (16.8) years; p < 0.001), with hypertension (57.0% vs. 47.7%; p < 0.001), obesity (26.4% vs. 19.3%; p < 0.0001), and multimorbidity prevalence (20.6% vs. 16.1%; p < 0.001). These patients had higher values (mean (95% CI)) of C-reactive protein (CRP) (86 (32.7-160) vs. 49.3 (16-109) mg/dL; p < 0.001), ferritin (791 (393-1534) vs. 470 (236- 996) ”g/dL; p < 0.001), D dimer (750 (430-1400) vs. 617 (345-1180) ”g/dL; p < 0.001), and lower Sp02/Fi02 (266 (91.1) vs. 301 (101); p < 0.001). Since June 2020, there was an increment in the use of CTs (March vs. September; p < 0.001). Overall, 20% did not receive steroids, and 40% received less than 200 mg accumulated prednisone equivalent dose (APED). Severe patients are treated with higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%. Conclusions: Patients with greater comorbidity, severity, and inflammatory markers were those treated with CTs. In severe patients, there is a trend towards the use of higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%
New insights into the genetic etiology of Alzheimer's disease and related dementias.
Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE Δ4 allele
New insights into the genetic etiology of Alzheimer's disease and related dementias
Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE Δ4 allele
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