3,832 research outputs found
Iris recognition using the JAVAVis Library
This project has been created to develop a
biometric identification system through a man’s iris using a
computer to perform the processing of the pictures. To develop
this application, and to differentiate the project from others
who have already implemented, we have used the image
processing library JAVAVis and JAVA as a programming
language
Asthma, obesity and diet
El asma y la obesidad son dos trastornos de gran
impacto en la salud pública que han aumentado su prevalencia
en los últimos años. Numerosos estudios han relacionado
ambas entidades.
La mayoría de los estudios prospectivos demuestran
que la obesidad es un factor de riesgo para el diagnóstico
“de novo” de asma. Además, los resultados de diversos
estudios sugieren que así como la ganancia de peso
aumenta el riesgo de asma, la pérdida mejora su evolución.
En general, los estudios prospectivos encuentran
una asociación positiva entre el índice de masa corporal
(IMC) basal y el posterior desarrollo de asma, lo que
sugiere que es el exceso de peso el que podría favorecer el
desarrollo de asma, aunque estos resultados no son tan
concluyentes cuando se estudia la asociación entre hiperreactividad
bronquial con el IMC.
Existen distintos factores que podrían explicar esta
asociación. La obesidad es capaz de reducir la compliance
pulmonar, los volúmenes pulmonares y el diámetro de de
las vías respiratorias periféricas, así como alterar los
volúmenes sanguíneos pulmonares y la relación ventilación-
perfusión. Además, el aumento del funcionamiento
normal del tejido adiposo en sujetos obesos conduce a un
estado proinflamatorio sistémico, que produce un
aumento de las concentraciones séricas de numerosas
citoquinas, fracciones solubles de sus receptores y quimiocinas.
Muchos de estos mediadores son sintetizados y
secretados por células del tejido adiposo y reciben el nombre
genérico de adipocinas, entre las que se incluyen IL-6,
IL-10, eotaxina, TNF- , TGF- 1, PCR, leptina y adiponectina.
Por último, se han identificado regiones específicas
del genoma humano que están relacionadas tanto con
el asma como con la obesidad.
La mayoría de los estudios apuntan a que la obesidad
es capaz de aumentar la prevalencia y la incidencia de
asma, aunque este efecto parece ser moderado. El tratamiento
de los asmáticos obesos debe incluir un programa
de control de peso.Asthma and obesity have a considerable impact on
public health and their prevalence has increased in recent
years. Numerous studies have linked both disorders.
Most prospective studies show that obesity is a risk factor
for asthma and have found a positive correlation between
baseline body mass index (BMI) and the subsequent
development of asthma, although these results are not
conclusive when studying the association between airway
hyperresponsiveness with BMI. Furthermore, several
studies suggest that whereas weight gain increases the
risk of asthma, weight loss improves the course of the illness.
Different factors could explain this association. Obesity
is capable of reducing pulmonary compliance, lung
volumes and the diameter of peripheral respiratory airways
as well as affecting the volume of blood in the lungs
and the ventilation-perfusion relationship. Furthermore,
the increase in the normal functioning of adipose tissue in
obese subjects leads to a systemic proinflammatory state,
which produces a rise in the serum concentrations of several
cytokines, the soluble fractions of their receptors and
chemokines. Many of these mediators are synthesized
and secreted by cells from adipose tissue and receive the
generic name of adipokines, including IL-6, IL-10,
eotaxin, TNF- , TGF- 1, PCR, leptin y adiponectin.
Finally, specific regions of the human genome which are
related to both asthma and obesity have been identified.
Most studies point out that obesity is capable of
increasing the prevalence and incidence of asthma,
although this effect appears to be modest. The treatment
of obese asthmatics must include a weight control progra
The space density distribution of galaxies in the absolute magnitude - rotation velocity plane: a volume-complete Tully-Fisher relation from CALIFA stellar kinematics
The space density distribution of galaxies in the absolute magnitude -
rotation velocity plane: a volume-complete Tully-Fisher relation from CALIFA
stellar kinematicsComment: Accepted to A&
The merging/AGN connection II. Ionization of the circumnuclear regions
We report the first results of a study of a sample of 20 galaxy
mergers/interacting systems, using the VIMOS and PMAS integral field
spectrographs. For each object, we extracted the integrated spectrum of the
central regions and analyzed the ionization state using classical diagnostic
diagrams (Veilleux & Osterbrock 1987). There is evidence of AGN ionization in 4
of the objects, i.e. 20% of the sample, a considerably higher fraction than
found in previous studies ~4%Comment: 4 pages, 2 figures, accepted for publishing in A&A Letter
Central star formation and metallicity in CALIFA interacting galaxies
We use optical integral-field spectroscopic (IFS) data from 103 nearby
galaxies at different stages of the merging event, from close pairs to merger
remnants provided by the CALIFA survey, to study the impact of the interaction
in the specific star formation and oxygen abundance on different galactic
scales. To disentangle the effect of the interaction and merger from internal
processes, we compared our results with a control sample of 80 non-interacting
galaxies. We confirm the moderate enhancement (2-3 times) of specific star
formation for interacting galaxies in central regions as reported by previous
studies; however, the specific star formation is comparable when observed in
extended regions. We find that control and interacting star-forming galaxies
have similar oxygen abundances in their central regions, when normalized to
their stellar masses. Oxygen abundances of these interacting galaxies seem to
decrease compared to the control objects at the large aperture sizes measured
in effective radius. Although the enhancement in central star formation and
lower metallicities for interacting galaxies have been attributed to tidally
induced inflows, our results suggest that other processes such as stellar
feedback can contribute to the metal enrichment in interacting galaxies.Comment: 9 pages, 9 figures. Accepted for publication in Astronomy &
Astrophysic
A gliclazide complex based on palladium towards Alzheimer's disease: Promising protective activity against Aβ-induced toxicity in: C. elegans
A new palladium coordination compound based on gliclazide with the chemical formula [Pd(glz)2] (where glz = gliclazide) has been synthesized and characterised. The structural characterization reveals that this material consists of mononuclear units formed by a Pd2+ ion coordinated to two molecules of the glz ligand, in which palladium ions exhibit a distorted plane-square coordination sphere. This novel material behaves like a good and selective inhibitor of butyrylcholinesterase, one of the most relevant therapeutic targets against Alzheimer's disease. Analysis of the enzyme kinetics showed a mixed mode of inhibition, the title compound being capable of interacting with both the free enzyme and the enzyme-substrate complex. Finally, the palladium compound shows promising protective activity against Aβ-induced toxicity in the Caenorhabditis elegans model, which has never been reported.he authors gratefully acknowledge funding support from the Spanish Ministry of Science, Innovation and Universities (PGC2018-102052-B-C21 and PID2020-116460RB-I00) and the Junta de Andalućıa (FQM-394 and FQM-134). The authors gratefully acknowledge the funding support of FEDER/Junta de Andalućıa Consejería de Economía y Conocimiento, Grant B-AGR-193-UGR18. O. L. and J. G. F. B. also thank Grant PID2020-116460RB-I00 funded by MCIN/AEI/10.13039/50110 0011033. S. R. acknowledge the Juan de la Cierva Fellowship (IJC2019-038894-I)
Ionized gas kinematics of galaxies in the CALIFA survey : I. Velocity fields, kinematic parameters of the dominant component, and presence of kinematically distinct gaseous systems
J.M.A. acknowledges support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild). Date of Acceptance: 01/08/2014Context. Ionized gas kinematics provide important clues to the dynamical structure of galaxies and hold constraints to the processes driving their evolution. Aims. The motivation of this work is to provide an overall characterization of the kinematic behavior of the ionized gas of the galaxies included in the Calar Alto Legacy Integral field Area (CALIFA), offering kinematic clues to potential users of the CALIFA survey for including kinematical criteria in their selection of targets for specific studies. From the first 200 galaxies observed by CALIFA survey in its two configurations, we present the two-dimensional kinematic view of the 177 galaxies satisfaying a gas content/detection threshold. Methods. After removing the stellar contribution, we used the cross-correlation technique to obtain the radial velocity of the dominant gaseous component for each spectrum in the CALIFA data cubes for different emission lines (namely, [O ii] λλ3726,3729, [O iii] λλ4959,5007, Hα+[N ii] λλ6548,6584, and [SII]λλ6716,6730). The main kinematic parameters measured on the plane of the sky were directly derived from the radial velocities with no assumptions on the internal prevailing motions. Evidence of the presence of several gaseous components with different kinematics were detected by using [O iii] λλ4959,5007 emission line profiles. Results. At the velocity resolution of CALIFA, most objects in the sample show regular velocity fields, although the ionized-gas kinematics are rarely consistent with simple coplanar circular motions. Thirty-five percent of the objects present evidence of a displacement between the photometric and kinematic centers larger than the original spaxel radii. Only 17% of the objects in the sample exhibit kinematic lopsidedness when comparing receding and approaching sides of the velocity fields, but most of them are interacting galaxies exhibiting nuclear activity (AGN or LINER). Early-type (E+S0) galaxies in the sample present clear photometric-kinematic misaligments. There is evidence of asymmetries in the emission line profiles in 117 out of the 177 analyzed galaxies, suggesting the presence of kinematically distinct gaseous components located at different distances from the optical nucleus. The kinematic decoupling between the dominant and secondary component/s suggested by the observed asymmetries in the profiles can be characterized by a limited set of parameters. Conclusions. This work constitutes the first determination of the ionized gas kinematics of the galaxies observed in the CALIFA survey. The derived velocity fields, the reported kinematic distortions/peculiarities and the identification of the presence of several gaseous components in different regions of the objects might be used as additional criteria for selecting galaxies for specific studies.Publisher PDFPeer reviewe
The effects of spatial resolution on Integral Field Spectrograph surveys at different redshifts. The CALIFA perspective
Over the past decade, 3D optical spectroscopy has become the preferred tool
for understanding the properties of galaxies and is now increasingly used to
carry out galaxy surveys. Low redshift surveys include SAURON, DiskMass,
ATLAS3D, PINGS and VENGA. At redshifts above 0.7, surveys such as MASSIV, SINS,
GLACE, and IMAGES have targeted the most luminous galaxies to study mainly
their kinematic properties. The on-going CALIFA survey () is the
first of a series of upcoming Integral Field Spectroscopy (IFS) surveys with
large samples representative of the entire population of galaxies. Others
include SAMI and MaNGA at lower redshift and the upcoming KMOS surveys at
higher redshift. Given the importance of spatial scales in IFS surveys, the
study of the effects of spatial resolution on the recovered parameters becomes
important. We explore the capability of the CALIFA survey and a hypothetical
higher redshift survey to reproduce the properties of a sample of objects
observed with better spatial resolution at lower redshift. Using a sample of
PINGS galaxies, we simulate observations at different redshifts. We then study
the behaviour of different parameters as the spatial resolution degrades with
increasing redshift.Comment: 20 pages, 16 figures. Accepted for publication in A&
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