43 research outputs found
Chapter Monitoring coastal areas: a brief history of measuring instruments for solar radiation
The first measuring instruments of solar radiation, for meteorological aims, were made only in 1800s. In 1896 OMI established a commission for radiometry which led, in 1905, to choose Ångström pyrheliometer as standard instrument. Later, radiometers were built with a chart recorder for measuring solar radiation components. Instruments using thermopile or photocell as sensitive element were made. From 1980s radiometers with data logger were built. In 2000s devices were developed for measuring solar radiation components in water column, for studies on physical and biological marine quantities
Chapter Alexander von Humboldt, da 250 anni il teorizzatore dello studio interdisciplinare dell’ambiente
In 19th century birth of the term scientist led to beginning of Sciences professionalization and end of Nature eclectic scholar, of which Humboldt was the last exponent. Humboldt managed to connect all disciplines in a holistic vision of the world: organic and inorganic nature form a single system of active forces; all the organisms of Earth are linked as a family sharing same home. Today, given the anthropogenic damage caused to Nature, it needs to reconsider his unified vision, establishing connections between scholars of various disciplines, for an organic and global vision of Environment
Superdense galaxies and the mass-size relation at low redshift
We search for massive and compact galaxies (superdense galaxies, hereafter
SDGs) at z=0.03-0.11 in the Padova-Millennium Galaxy and Group Catalogue, a
spectroscopically complete sample representative of the local Universe general
field population. We find that compact galaxies with radii and mass densities
comparable to high-z massive and passive galaxies represent 4.4% of all
galaxies with stellar masses above 3 X 10^10 M_sun, yielding a number density
of 4.3 X 10^-4 h^3 Mpc^-3. Most of them are S0s (70%) or ellipticals (23%), are
red and have intermediate-to-old stellar populations, with a median
luminosity-weighted age of 5.4 Gyr and a median mass-weighted age of 9.2 Gyr.
Their velocity dispersions and dynamical masses are consistent with the small
radii and high stellar mass estimates. Comparing with the WINGS sample of
cluster galaxies at similar redshifts, the fraction of superdense galaxies is
three times smaller in the field than in clusters, and cluster SDGs are on
average 4 Gyr older than field SDGs. We confirm the existence of a universal
trend of smaller radii for older luminosity-weighted ages at fixed galaxy mass.
On top of the well known dependence of stellar age on galaxy mass, the
luminosity-weighted age of galaxies depends on galaxy compactness at fixed
mass, and, for a fixed mass and radius, on environment. This effect needs to be
taken into account in order not to overestimate the evolution of galaxy sizes
from high- to low-z. Our results and hierarchical simulations suggest that a
significant fraction of the massive compact galaxies at high-z have evolved
into compact galaxies in galaxy clusters today. When stellar age and
environmental effects are taken into account, the average amount of size
evolution of individual galaxies between high- and low-z is mild, a factor
~1.6. (abridged)Comment: ApJ, in pres
Surface photometry of WINGS galaxies with GASPHOT
Aims. We present the B-, V- and K-band surface photometry catalogs obtained
running the automatic software GASPHOT on galaxies from the WINGS cluster
survey having isophotal area larger than 200 pixels. The catalogs can be
downloaded at the Centre de Donnees Astronomiques de Strasbourg (CDS). Methods.
We outline the GASPHOT performances and compare our surface photometry with
that obtained by SExtractor, GALFIT and GIM2D. This analysis is aimed at
providing statistical information about the accuracy generally achieved by the
softwares for automatic surface photometry of galaxies. Results. For each
galaxy and for each photometric band the GASPHOT catalogs provide the
parameters of the Sersic law best-fitting the luminosity profiles. They are:
the sky coordinates of the galaxy center (R:A:; DEC:), the total magnitude (m),
the semi-major axis of the effective isophote (Re), the Sersic index (n), the
axis ratio (b=a) and a flag parameter (QFLAG) giving a global indication of the
fit quality. The WINGS-GASPHOT database includes 41,463 galaxies in the B-band,
42,275 in the V-band, and 71,687 in the K-band. We find that the bright
early-type galaxies have larger Sersic indices and effective radii, as well as
redder colors in their center. In general the effective radii increase
systematically from the K- to the V- and B-band. Conclusions. The GASPHOT
photometry turns out to be in fairly good agreement with the surface photometry
obtained by GALFIT and GIM2D, as well as with the aperture photometry provided
by SExtractor. The main advantages of GASPHOT with respect to other tools are:
(i) the automatic finding of the local PSF; (ii) the short CPU time of
execution; (iii) the remarkable stability against the choice of the initial
guess parameters. All these characteristics make GASPHOT an ideal tool for
blind surface photometry of large galaxy samples in wide-field CCD mosaics.Comment: 14 pages, 9 figure
Balance Dysfunction in Parkinson\u27s Disease: The Role of Posturography in Developing a Rehabilitation Program
Balance dysfunction (BD) in Parkinson\u27s disease (PD) is a disabling symptom, difficult to treat and predisposing to falls. The dopaminergic drugs or deep brain stimulation does not always provide significant improvements of BD and rehabilitative approaches have also failed to restore this condition. In this study, we investigated the suitability of quantitative posturographic indicators to early identify patients that could develop disabling BD. Parkinsonian patients not complaining of a subjective BD and controls were tested using a posturographic platform (PP) with open eyes (OE) and performing a simple cognitive task [counting (OEC)]. We found that patients show higher values of total standard deviation (SD) of body sway and along the medio-lateral (ML) axis during OE condition. Furthermore, total and ML SD of body sway during OE condition and total SD of body sway with OEC were higher than controls also in a subgroup of patients with normal Berg Balance Scale. We conclude that BD in Parkinsonian patients can be discovered before its appearance using a PP and that these data may allow developing specific rehabilitative treatment to prevent or delay their onset
Rapamycin treatment for amyotrophic lateral sclerosis: Protocol for a phase II randomized, double-blind, placebo-controlled, multicenter, clinical trial (RAP-ALS trial)
Genome-wide Analyses Identify KIF5A as a Novel ALS Gene
To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494 controls. Through both approaches, we identified kinesin family member 5A (KIF5A) as a novel gene associated with ALS. Interestingly, mutations predominantly in the N-terminal motor domain of KIF5A are causative for two neurodegenerative diseases: hereditary spastic paraplegia (SPG10) and Charcot-Marie-Tooth type 2 (CMT2). In contrast, ALS-associated mutations are primarily located at the C-terminal cargo-binding tail domain and patients harboring loss-of-function mutations displayed an extended survival relative to typical ALS cases. Taken together, these results broaden the phenotype spectrum resulting from mutations in KIF5A and strengthen the role of cytoskeletal defects in the pathogenesis of ALS.Peer reviewe
Chapter Monitoring coastal areas: a brief history of measuring instruments for solar radiation
The first measuring instruments of solar radiation, for meteorological aims, were made only in 1800s. In 1896 OMI established a commission for radiometry which led, in 1905, to choose Ångström pyrheliometer as standard instrument. Later, radiometers were built with a chart recorder for measuring solar radiation components. Instruments using thermopile or photocell as sensitive element were made. From 1980s radiometers with data logger were built. In 2000s devices were developed for measuring solar radiation components in water column, for studies on physical and biological marine quantities