4,510 research outputs found
A recalibration of IUE NEWSIPS low dispersion data
While the low dispersion IUE NEWSIPS data products represent a significant
improvement over original IUE SIPS data, they still contain serious systematic
effects which compromise their utility for certain applications. We show that
NEWSIPS low resolution data are internally consistent to only 10-15% at best,
with the majority of the problem due to time dependent systematic effects. In
addition, the NEWSIPS flux calibration is shown to be inconsistent by nearly
10%.
We examine the origin of these problems and proceed to formulate and apply
algorithms to correct them to ~ 3% level -- a factor of 5 improvement in
accuracy. Because of the temporal systematics, transforming the corrected data
to the IUE flux calibration becomes ambiguous. Therefore, we elect to transform
the corrected data onto the HST FOS system. This system is far more
self-consistent, and transforming the IUE data to it places data from both
telescopes on a single system.
Finally, we argue that much of the remaining 3% systematic effects in the
corrected data is traceable to problems with the NEWSIPS intensity
transformation function (ITF). The accuracy could probably be doubled by
rederiving the ITF.Comment: Submitted to ApJ Supplement, 35 pages, 13 figures, LaTeX - AASTEX
aas2pp4.st
Quality of Government and Well-being: An Empirical Analysis of 158 European Regions
The aim of the study is twofold: on the one hand, it assesses the association between well-being and the quality of government, on the other it evaluates the impact exerted on the same well-being by the different components into which the quality of government can be broken down. The analysis is conducted at the regional level. A
composite indicator derived from OECD data on regional well-being is used to assess its association with the quality of government. The latter is measured using the European Quality of Government Survey Index (EQI) data. The EQI breaks down the quality of government into three key elements: the impartiality of administration, the quality of services provided and the degree of corruption. The association between well-being and quality of government is verified considering, at first, the EQI index as a whole, being the product of the three different components, and then separately considering its key elements.The results confirmed the existence of a strong positive association between well-being and the overall quality of
government, as between the former and the single components of the EQI index. Furthermore, the same
association is observed when the assessment is made on the whole sample, but also when subsamples are made,
considering the geographical macro-area to which the regions belong
The Influence of Stellar Wind Variability on Measurements of Interstellar O VI Along Sightlines to Early-Type Stars
A primary goal of the FUSE mission is to understand the origin of the O VI
ion in the interstellar medium of the Galaxy and the Magellanic Clouds. Along
sightlines to OB-type stars, these interstellar components are usually blended
with O VI stellar wind profiles, which frequently vary in shape. In order to
assess the effects of this time-dependent blending on measurements of the
interstellar O VI lines, we have undertaken a mini-survey of repeated
observations toward OB-type stars in the Galaxy and the Large Magellanic Cloud.
These sparse time series, which consist of 2-3 observations separated by
intervals ranging from a few days to several months, show that wind variability
occurs commonly in O VI (about 60% of a sample of 50 stars), as indeed it does
in other resonance lines. However, in the interstellar O VI 1032
region, the O VI 1038 wind varies only in 30% of the cases. By
examining cases exhibiting large amplitude variations, we conclude that
stellar-wind variability {\em generally} introduces negligible uncertainty for
single interstellar O VI components along Galactic lines of sight, but can
result in substantial errors in measurements of broader components or blends of
components like those typically observed toward stars in the Large Magellanic
Cloud. Due to possible contamination by discrete absorption components in the
stellar O VI line, stars with terminal velocities greater than or equal to the
doublet separation (1654 km/s) should be treated with care.Comment: Accepted for publication in the Astrophysical Journal Lette
The District Energy-Efficient Retrofitting of Torrelago (Laguna de Duero – Spain)
The urban growth is estimated to reach up the 66 % by 2050 and consequently the need of resources within the cities will increase significantly. This, combined with the 40 % of energy consumption and 36 % of CO2 emissions of the building sector, makes necessary to accelerate the transition towards more sustainable cities. The CITyFiED project contributes to this transition, aiming to develop an innovative and holistic methodological approach for energy-efficient district renovation and deliver three large scale demonstration cases in the cities of Lund (Sweden), Laguna de Duero (Spain) and Soma (Turkey). CITyFiED methodology consists of several phases that ease the decision-making tasks towards the district renovation, considering the energy efficiency as the main pillar and local authorities as clients. For the case of Torrelago district (Spain) the intervention consists of a set of energy conservative measures including the facÄ…de retrofitting of 143.025 m2 of living space in 31 twelve-storey buildings; the renovation of the district heating network with a new biomass thermal plant; the integration of renewable energy sources, including a micro-cogeneration system, and the installation of individual smart meters. After the renovation action, one-year monitoring campaign is ongoing. The CITyFiED monitoring platform will collect information from the energy systems and deliver environmental, technical, economic and social key performance indicators by March 2019. At the end of the project the achievement of the predefined goals will be verified: Up to 36 % of energy saving and 3,429 tons-CO2/yr emissions saving covering the 59,4 % of the energy consumption with renewable sources.The research and results presented in this paper evolve from activities related to the CITyFiED project, which has received funding from the European Commission under the Grant Agreement no. 609129. This article is the result of cooperative research work of many experts from various countries and we would like to gratefully acknowledge the rest of the CITyFiED partners
The Distance to the Large Magellanic Cloud from the Eclipsing Binary HV2274
The distance to the Large Magellanic Cloud (LMC) is crucial for the
calibration of the Cosmic Distance Scale. We derive a distance to the LMC based
on an analysis of ground-based photometry and HST-based spectroscopy and
spectrophotometry of the LMC eclipsing binary system HV2274. Analysis of the
optical light curve and HST/GHRS radial velocity curve provides the masses and
radii of the binary components. Analysis of the HST/FOS UV/optical
spectrophotometry provides the temperatures of the component stars and the
interstellar extinction of the system. When combined, these data yield a
distance to the binary system. After correcting for the location of HV2274 with
respect to the center of the LMC, we find d(LMC) = 45.7 +/- 1.6 kpc or DM(LMC)
= 18.30 +/- 0.07 mag. This result, which is immune to the metallicity-induced
zero point uncertainties that have plagued other techniques, lends strong
support to the ``short'' LMC distance scale as derived from a number of
independent methods.Comment: 6 pages, including 2 pages of figures. Newly available optical (B and
V) photometry has revealed -- and allowed the elimination of -- a systematic
error in the previously reported determination of E(B-V) for HV2274. The new
result is E(B-V) = 0.12 mag (as compared to the value of 0.083 reported in
the original submission) and produces a DECREASE in the distance modulus of
HV2274 by 0.12 mag. ApJ Letters, in pres
The effect of a diet supplement containing S-acetyl-glutathione (SAG) and other antioxidant natural ingredients on glutathione peroxidase in healthy dogs: a pilot study
Oxidative stress is common in several human and veterinary conditions and it is associated to alteration of the glutathione peroxidase (GPx) level. GPx is an enzyme present in erythrocytes, kidney, and liver and it has a role in protecting against oxidative damage. In this randomised double-blinded control trial on healthy dogs, we present findings indicating that the administration for a total of 35 days of a supplement containing S-acetyl-glutathione (SAG) alongside other antioxidant natural ingredients, leads to an increase in the GPx level. Furthermore, the supplement positively changes liver blood parameters, even in healthy dogs. These preliminary results hold promise for conducting new studies using the same supplement on dogs affected by liver conditions, thereby confirming its antioxidant effects and the potential improvement of altered blood parameters
Objective assessment of walking impairments in myotonic dystrophy by means of a wearable technology and a novel severity index
Myotonic dystrophy type 1 (DM1) is a genetic inherited autosomal dominant disease characterized by multisystem involvement, including muscle, heart, brain, eye, and endocrine system. Although several methods are available to evaluate muscle strength, endurance, and dexterity, there are no validated outcome measures aimed at objectively evaluating qualitative and quantitative gait alterations. Advantageously, wearable sensing technology has been successfully adopted in objectifying the assessment of motor disabilities in different medical occurrences, so that here we consider the adoption of such technology specifically for DM1. In particular, we measured motor tasks through inertial measurement units on a cohort of 13 DM1 patients and 11 healthy control counterparts. The motor tasks consisted of 16 meters of walking both at a comfortable speed and fast pace. Measured data consisted of plantar-flexion and dorsi-flexion angles assumed by both ankles, so to objectively evidence the footdrop behavior of the DM1 disease, and to define a novel severity index, termed SI-Norm2, to rate the grade of walking impairments. According to the obtained results, our approach could be useful for a more precise stratification of DM1 patients, providing a new tool for a personalized rehabilitation approach
A new FSA approach for in situ -ray spectroscopy
An increasing demand of environmental radioactivity monitoring comes both
from the scientific community and from the society. This requires accurate,
reliable and fast response preferably from portable radiation detectors. Thanks
to recent improvements in the technology, -spectroscopy with sodium
iodide scintillators has been proved to be an excellent tool for in-situ
measurements for the identification and quantitative determination of
-ray emitting radioisotopes, reducing time and costs. Both for
geological and civil purposes not only K, U, and Th have
to be measured, but there is also a growing interest to determine the
abundances of anthropic elements, like Cs and I, which are used
to monitor the effect of nuclear accidents or other human activities.
The Full Spectrum Analysis (FSA) approach has been chosen to analyze the
-spectra. The Non Negative Least Square (NNLS) and the energy
calibration adjustment have been implemented in this method for the first time
in order to correct the intrinsic problem related with the
minimization which could lead to artifacts and non physical results in the
analysis.
A new calibration procedure has been developed for the FSA method by using in
situ -spectra instead of calibration pad spectra. Finally, the new
method has been validated by acquiring -spectra with a 10.16 cm x 10.16
cm sodium iodide detector in 80 different sites in the Ombrone basin, in
Tuscany. The results from the FSA method have been compared with the laboratory
measurements by using HPGe detectors on soil samples collected in the different
sites, showing a satisfactory agreement between them. In particular, the
Cs isotopes has been implemented in the analysis since it has been
found not negligible during the in-situ measurements.Comment: accepted by Science of Total Environment: 8 pages, 10 figures, 3
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