216 research outputs found
Patrimonio minero-metalúrgico de Rodalquilar: Metodología de catalogación y resultados
Para estudiar y conservar el Patrimonio, es necesario desarrollar una metodología para la catalogación y valoración de los elementos patrimoniales. Un caso real catalogación de una antigua zona minera; Rodalquilar (Almería) en el Sudeste de España, es el objetivo del presente trabajo
A new scheme of radiation transfer in H II regions including transient heating of grains
A new scheme of radiation transfer for understanding infrared spectra of H II
regions, has been developed. This scheme considers non-equilibrium processes
(e. g. transient heating of the very small grains, VSG; and the polycyclic
aromatic hydrocarbon, PAH) also, in addition to the equilibrium thermal
emission from normal dust grains (BG). The spherically symmetric interstellar
dust cloud is segmented into a large number of "onion skin" shells in order to
implement the non-equilibrium processes. The scheme attempts to fit the
observed SED originating from the dust component, by exploring the following
parameters : (i) geometrical details of the dust cloud, (ii) PAH size and
abundance, (iii) composition of normal grains (BG), (iv) radial distribution of
all dust (BG, VSG & PAH).
The scheme has been applied to a set of five compact H II regions (IRAS
18116- 1646, 18162-2048, 19442+2427, 22308+5812 & 18434-0242) whose spectra are
available with adequate spectral resolution. The best fit models and inferences
about the parameters for these sources are presented.Comment: 16 pages total including 3 tables and 2 figure
Optical BVI Imaging and HI Synthesis Observations of the Dwarf Irregular Galaxy ESO 364-G 029
As part of an effort to enlarge the number of well-studied Magellanic-type
galaxies, we obtained broadband optical imaging and neutral hydrogen radio
synthesis observations of the dwarf irregular galaxy ESO 364-G 029. The optical
morphology characteristically shows a bar-like main body with a one-sided
spiral arm, an approximately exponential light distribution, and offset
photometric and kinematic centers. The HI distribution is mildly asymmetric
and, although slightly offset from the photometric center, roughly follows the
optical brightness distribution, extending to over 1.2 Holmberg radii (where
mu_B = 26.5 mag/arcsec^2). In particular, the highest HI column densities
closely follow the bar, one-arm spiral, and a third optical extension. The
rotation is solid-body in the inner parts but flattens outside of the optical
extent. The total HI flux F_HI = 23.1 pm 1.2 Jy km/s, yielding a total HI mass
M_HI= (6.4 pm 1.7) x 10^8 Msun (for a distance D = 10.8 pm 1.4 Mpc) and a total
HI mass-to-blue-luminosity ratio M_HI/L_B = (0.96 pm 0.14) Msun / Lsun,B
(distance independent). The HI data suggest a very complex small-scale HI
structure, with evidence of large shells and/or holes, but deeper observations
are required for a detailed study. Follow-up observations are also desirable
for a proper comparison with the Large Magellanic Cloud, where despite an
optical morphology very similar to ESO 364-G 029 the HI bears little
resemblance to the optical.Comment: 10 pages, 11 figures, accepted by A&
Turbulence and galactic structure
Interstellar turbulence is driven over a wide range of scales by processes
including spiral arm instabilities and supernovae, and it affects the rate and
morphology of star formation, energy dissipation, and angular momentum transfer
in galaxy disks. Star formation is initiated on large scales by gravitational
instabilities which control the overall rate through the long dynamical time
corresponding to the average ISM density. Stars form at much higher densities
than average, however, and at much faster rates locally, so the slow average
rate arises because the fraction of the gas mass that forms stars at any one
time is low, ~10^{-4}. This low fraction is determined by turbulence
compression, and is apparently independent of specific cloud formation
processes which all operate at lower densities. Turbulence compression also
accounts for the formation of most stars in clusters, along with the cluster
mass spectrum, and it gives a hierarchical distribution to the positions of
these clusters and to star-forming regions in general. Turbulent motions appear
to be very fast in irregular galaxies at high redshift, possibly having speeds
equal to several tenths of the rotation speed in view of the morphology of
chain galaxies and their face-on counterparts. The origin of this turbulence is
not evident, but some of it could come from accretion onto the disk. Such high
turbulence could help drive an early epoch of gas inflow through viscous
torques in galaxies where spiral arms and bars are weak. Such evolution may
lead to bulge or bar formation, or to bar re-formation if a previous bar
dissolved. We show evidence that the bar fraction is about constant with
redshift out to z~1, and model the formation and destruction rates of bars
required to achieve this constancy.Comment: in: Penetrating Bars through Masks of Cosmic Dust: The Hubble Tuning
Fork strikes a New Note, Eds., K. Freeman, D. Block, I. Puerari, R. Groess,
Dordrecht: Kluwer, in press (presented at a conference in South Africa, June
7-12, 2004). 19 pgs, 5 figure
Propuesta de un plan de negocio, basado en tecnolog?a, para atenci?n de consultas e incidentes relacionados a dispositivos electr?nicos
El servicio de soporte t?cnico se ha venido prestando de manera tradicional a lo largo del tiempo. Sin embargo, no se ha evidenciado la existencia de alg?n proveedor, que brinde este servicio de manera integral, siendo independiente del dispositivo, marca y plataforma. En ese sentido, la presente tesis, propone un modelo de negocio que, fundament?ndose en tecnolog?a como elemento diferenciador, busca atender las consultas e incidentes de los usuarios de manera integral, eliminando la complejidad de buscar al proveedor que compete un determinado incidente. Asimismo, el uso de tecnolog?a, permitir? brindar un primer nivel de servicio totalmente gratuito, y otro pagado, que ser? el que generar?a ingresos a la empresa. En ambos casos, se buscar? maximizar la eficiencia en cuanto a operaciones y calidad del servicio. Finalmente, se ha contemplado tambi?n el uso de tecnolog?a anal?tica, que permita mejorar las operaciones de la empresa a lo largo del tiempo. Por ejemplo, mediante la consulta a bases de datos de conocimiento, lo cual permitir? una mayor eficiencia en la soluci?n de incidentes
Olfactory Enrichment Influences Adult Neurogenesis Modulating GAD67 and Plasticity-Related Molecules Expression in Newborn Cells of the Olfactory Bulb
The olfactory bulb (OB) is a highly plastic region of the adult mammalian brain characterized by continuous integration of inhibitory interneurons of the granule (GC) and periglomerular cell (PGC) types. Adult-generated OB interneurons are selected to survive in an experience-dependent way but the mechanisms that mediate the effects of experience on OB neurogenesis are unknown. Here we focus on the new-generated PGC population which is composed by multiple subtypes. Using paradigms of olfactory enrichment and/or deprivation combined to BrdU injections and quantitative confocal immunohistochemical analyses, we studied the effects of olfactory experience on adult-generated PGCs at different survival time and compared PGC to GC modulation. We show that olfactory enrichment similarly influences PGCs and GCs, increasing survival of newborn cells and transiently modulating GAD67 and plasticity-related molecules expression. However, PGC maturation appears to be delayed compared to GCs, reflecting a different temporal dynamic of adult generated olfactory interneuron integration. Moreover, olfactory enrichment or deprivation do not selectively modulate the survival of specific PGC phenotypes, supporting the idea that the integration rate of distinct PGC subtypes is independent from olfactory experience
Prenatal exposure of a girl with autism spectrum disorder to 'horsetail' (Equisetum arvense) herbal remedy and alcohol: a case report
Evaluating the organisational climate in Italian public healthcare institutions by means of a questionnaire
<p>Abstract</p> <p>Background</p> <p>By means of the ICONAS project, the Healthcare Agency of an Italian Region developed, and used a standardised questionnaire to quantify the organisational climate. The aims of the project were (a) to investigate whether the healthcare institutions were interested in measuring climate, (b) to estimate the range of applicability and reliability of the instrument, (c) to analyse the dimensions of climate among healthcare personnel, (d) to assess the differences among employees with different contractual positions.</p> <p>Methods</p> <p>The anonymous questionnaire containing 50 items, each with a scale from 1 to 10, was offered to the healthcare organisations, to be compiled during ad hoc meetings. The data were sent to the central project coordinator. The differences between highly specialised staff (mostly physicians) and other employees were assessed after descriptive statistical analysis of the single items. Both Principal Component Analysis and Factor Analysis were used.</p> <p>Results</p> <p>Ten healthcare organisations agreed to partecipate. The questionnaire was completed by 8691 employees out of 13202. The mean value of organisational climate was 4.79 (range 1–10). There were significant differences among single items and between the 2 groups of employees. Multivariate methods showed: (a) one principal component explained > 40% of the variance, (b) 7 factors summarised the data.</p> <p>Conclusion</p> <p>Italian healthcare institutions are interested in assessing organisational phenomena, especially after the reforms of the nineties. The instrument was found to be applicable and suitable for measuring organisational climate. Administration of the questionnaire leads to an acceptable response rate. Climate can be discribed by means of 7 underlying dimensions.</p
A preliminary investigation on the possible association between diminished copper availability and non-alcoholic fatty liver disease in epileptic patients treated with valproic acid
Enzyme-Catalyzed Macrocyclization of Long Unprotected Peptides
A glutathione S-transferase (GST) catalyzed macrocyclization reaction for peptides up to 40 amino acids in length is reported. GST catalyzes the selective SNAr reaction between an N-terminal glutathione (GSH, γ-Glu-Cys-Gly) tag and a C-terminal perfluoroaryl-modified cysteine on the same polypeptide chain. Cyclic peptides ranging from 9 to 24 residues were quantitatively produced within 2 h in aqueous pH = 8 buffer at room temperature. The reaction was highly selective for cyclization at the GSH tag, enabling the combination of GST-catalyzed ligation with native chemical ligation to generate a large 40-residue peptide macrocycle.Massachusetts Institute of Technology (MIT startup funds)National Institutes of Health (U.S.) (grant GM101762)Damon Runyon Cancer Research Foundation (Award)Sontag Foundation (Distinguished Scientist Award)Amgen Inc. (Summer Graduate Research Fellowship
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