325 research outputs found
Multidimensional Rovella-like attractors
We present a multidimensional flow exhibiting a Rovella-like attractor: a
transitive invariant set with a non-Lorenz-like singularity accumulated by
regular orbits and a multidimensional non-uniformly expanding invariant
direction. Moreover, this attractor has a physical measure with full support
but persists along certain0909.1033 submanifolds of the space of vector fields.
As in the 3-dimensional Rovella-like attractor, this example is not robust. The
construction introduces a class of multidimensional dynamics, whose suspension
provides the Rovella-like attractor, which are partially hyperbolic, and whose
quotient over stable leaves is a multidimensional endomorphism to which
Benedicks-Carleson type arguments are applied to prove non-uniform expansion.Comment: 45 pages, 14 figures; improved introduction with more citations to
other relevant related works. To appear in Journal of Differential Equation
Synthetic Conjugates of Ursodeoxycholic Acid Inhibit Cystogenesis in Experimental Models of Polycystic Liver Disease
Altres ajuts: Suported by IKERBASQUE, Basque foundation for Science (M.J. Perugorria and J.M. Banales), Spain; "Junta de Castilla y Leon" (J.J.G. Marin: SA06P17); "Diputación Foral Gipuzkoa" (J.M. Banales: DFG15/010, DFG16/004; M.J. Perugorria: DFG18/114, DFG19/081), BIOEF (Basque Foundation for Innovation and Health Research: EiTB Maratoia BIO15/CA/016/BD to J.M. Banales), Department of Health of the Basque Country (J.M. Banales: 2017111010; M.J. Perugorria: 2019111024), and Euskadi RIS3 (J.M. Banales: 2016222001, 2017222014, and 2018222029; 2019222054); La Caixa Scientific Foundation (J.M. Banales: HR17-00601); "Fundación Científica de la Asociación Española Contra el Cáncer" (AECC Scientific Foundation, to J.M. Banales and J.J.G. Marin); and "Centro Internacional sobre el Envejecimiento", Spain (J.J.G. Marin: OLD-HEPAMARKER, 0348-CIE-6-E). A. Santos-Laso by the Basque Government (PRE_2018_2_0195), and Pui Y. Lee-Law by the European Association for the Study of the Liver (EASL; Sheila Sherlock Award). Basque Government (F.P. Cossío: IT-324-07). I. Rivilla had a postdoctoral contract from the Donostia International Physics Center.Background and Aims: Polycystic liver diseases (PLDs) are genetic disorders characterized by progressive development of symptomatic biliary cysts. Current surgical and pharmacological approaches are ineffective, and liver transplantation represents the only curative option. Ursodeoxycholic acid (UDCA) and histone deacetylase 6 inhibitors (HDAC6is) have arisen as promising therapeutic strategies, but with partial benefits. Approach and Results: Here, we tested an approach based on the design, synthesis, and validation of a family of UDCA synthetic conjugates with selective HDAC6i capacity (UDCA-HDAC6i). Four UDCA-HDAC6i conjugates presented selective HDAC6i activity, UDCA-HDAC6i #1 being the most promising candidate. UDCA orientation within the UDCA-HDAC6i structure was determinant for HDAC6i activity and selectivity. Treatment of polycystic rats with UDCA-HDAC6i #1 reduced their hepatomegaly and cystogenesis, increased UDCA concentration, and inhibited HDAC6 activity in liver. In cystic cholangiocytes UDCA-HDAC6i #1 restored primary cilium length and exhibited potent antiproliferative activity. UDCA-HDAC6i #1 was actively transported into cells through BA and organic cation transporters. Conclusions: These UDCA-HDAC6i conjugates open a therapeutic avenue for PLDs
Evaluación de los costes de mantenimiento y restauración de edificios patrimoniales
En las últimas décadas, no se han adoptado protocolos de mantenimiento adecuados para la conservación y rehabilitación del patrimonio cultural. En España, el mantenimiento de estos edificios tiene, comúnmente, una naturaleza reactiva, estando condicionada por criterios subjetivos y por la existencia de fondos disponibles para la realización de las acciones de rehabilitación. Por tanto, es fundamental que los gestores del patrimonio construido tengan información relevante que ayude a tomar decisiones sobre la prioridad de intervención y las acciones preventivas a realizar en edificios patrimoniales. Existen cada vez más estudios relacionados con la definición de estrategias de mantenimiento adecuadas, que permitan mejorar el estado de conservación del patrimonio construido, con especial foco en la optimización de costos de mantenimiento empleados durante el ciclo de vida de estos edificios. Este trabajo identifica los factores que condicionan la decisión de intervenir en un conjunto de edificios patrimoniales, localizados en el sur de España. Se analizan las acciones de mantenimiento realizadas en un conjunto de 20 iglesias parroquiales y sus costes durante un período de 11 años (entre 2005 y 2015). En este estudio se evalúa la eficacia de las acciones realizadas, identificando los puntos fuertes y débiles de las intervenciones y estrategias adoptadas a lo largo del período de tiempo analizado. Los resultados obtenidos demuestran que las acciones de naturaleza reactiva deben ser minimizadas, para reducir los costes de mantenimiento. El conocimiento adquirido con las estrategias adoptadas en el pasado permite proporcionar información relevante para la planificación adecuada de futuras estrategias de mantenimient
Effects of Trihalomethanes on Liver Mitochondria
Introduction: Trihalomethanes (THMs), namely dibromochloromethane
(DBCM) and bromodichloromethane (BDCM), are disinfection
byproducts of chlorinated water. This experiment aimed to
evaluate the mitochondrial dysfunction induced by THMs at low
levels in a mouse model
The exposure of the hybrid detector of the Pierre Auger Observatory
The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays.
It consists of a surface array to measure secondary particles at ground level
and a fluorescence detector to measure the development of air showers in the
atmosphere above the array. The "hybrid" detection mode combines the
information from the two subsystems. We describe the determination of the
hybrid exposure for events observed by the fluorescence telescopes in
coincidence with at least one water-Cherenkov detector of the surface array. A
detailed knowledge of the time dependence of the detection operations is
crucial for an accurate evaluation of the exposure. We discuss the relevance of
monitoring data collected during operations, such as the status of the
fluorescence detector, background light and atmospheric conditions, that are
used in both simulation and reconstruction.Comment: Paper accepted by Astroparticle Physic
Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum
We report a first measurement for ultra-high energy cosmic rays of the
correlation between the depth of shower maximum and the signal in the water
Cherenkov stations of air-showers registered simultaneously by the fluorescence
and the surface detectors of the Pierre Auger Observatory. Such a correlation
measurement is a unique feature of a hybrid air-shower observatory with
sensitivity to both the electromagnetic and muonic components. It allows an
accurate determination of the spread of primary masses in the cosmic-ray flux.
Up till now, constraints on the spread of primary masses have been dominated by
systematic uncertainties. The present correlation measurement is not affected
by systematics in the measurement of the depth of shower maximum or the signal
in the water Cherenkov stations. The analysis relies on general characteristics
of air showers and is thus robust also with respect to uncertainties in
hadronic event generators. The observed correlation in the energy range around
the `ankle' at differs significantly from
expectations for pure primary cosmic-ray compositions. A light composition made
up of proton and helium only is equally inconsistent with observations. The
data are explained well by a mixed composition including nuclei with mass . Scenarios such as the proton dip model, with almost pure compositions, are
thus disfavoured as the sole explanation of the ultrahigh-energy cosmic-ray
flux at Earth.Comment: Published version. Added journal reference and DOI. Added Report
Numbe
Estrus cycle monitoring of captive collared peccaries (Pecari tajacu) in semiarid conditions
The small foreigner: new laws will promote the introduction of non-native zooplankton in Brazilian aquatic environments
Efeito do extrativismo seletivo de espécies arbóreas da Floresta Atlântica de Tabuleiros na matéria orgânica e outros atributos do solo
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