4,604 research outputs found
Political competition and societal veto players: the politics of pension reform in Southern Europe
While Southern European countries have pursued a series of pension reforms since the early 1990s, significant variation arises across them. Focusing on the concept of political replacement risk (the probability of a government being electorally punished for pursuing a given policy) and the changes in the labor movement's organizational structure, this article seeks to elucidate the differences in reform outcomes, in Italy, Greece, Portugal and Spain. Our analysis shows that significant reforms are implemented when governments face a high political replacement risk and the labor movement has undergone changes in its structure. By contrast, governments facing a stronger labor movement will generally be less effective at passing significant reforms, unless they can secure a strong support over the necessity to implement reforms
MachineâLearning Approaches to Tune Descriptors and Predict the Viscosities of Ionic Liquids and Their Mixtures
PTDC/EQU-EQU/30060/2017 UIDB/50006/2020This work consists on a new chemoinformatic approach based on two complementary artificial intelligence concepts. Random Forest and Kohonen neural network are applied on this context. The former provides a relevance measure of the numerical descriptors encoding either an ionic liquid or its mixtures. The code of a given chemical system is weighted according that relevance measure. The Kohonen neural network is trained with a set of weighted chemical systems. The next step comprises the use of the trained neural network as platform to obtain a tuned profile of numerical descriptors representing a generical chemical system. The tuning mechanism involves the topology of a chemical systemâencoding vector in the neural network. The last step comprises the use of the tuned chemical systems to build predictive models of viscosities. The MOLMAP encoding technology is applied to represent ionic liquid systems and its mixtures.publishersversionpublishe
The Chemical Enrichment History of the Small Magellanic Cloud and Its Gradients
We present stellar metallicities derived from Ca II triplet spectroscopy in
over 350 red giant branch stars in 13 fields distributed in different positions
in the SMC, ranging from 1\arcdeg\@ to 4\arcdeg\@ from its center.
In the innermost fields the average metallicity is [Fe/H] . This value
decreases when we move away towards outermost regions. This is the first
detection of a metallicity gradient in this galaxy. We show that the
metallicity gradient is related to an age gradient, in the sense that more
metal-rich stars, which are also younger, are concentrated in the central
regions of the galaxy.Comment: 30 pages, 13 figures, accepted for publication in Astronomical
Journa
A Numerical Case Study of Secondary Marine Cyclogenesis Sensitivity to Initial Error and Varying Physical Processes
Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. I. Abundances and Velocities for a Sample of Clusters
We have obtained near-infrared spectra covering the Ca II triplet lines for a
number of stars associated with 16 SMC clusters using the VLT + FORS2. These
data compose the largest available sample of SMC clusters with
spectroscopically derived abundances and velocities. Our clusters span a wide
range of ages and provide good areal coverage of the galaxy. Cluster members
are selected using a combination of their positions relative to the cluster
center as well as their abundances and radial velocities. We determine mean
cluster velocities to typically 2.7 km/s and metallicities to 0.05 dex (random
errors), from an average of 6.4 members per cluster. (continued in paper)Comment: 68 pages, 15 figures, Accepted to AJ Reason for the replacement:
section 7 and fig. 9 have been modified according referee suggestion
Bio-inspired Systems for Carbon Dioxide Capture, Sequestration and Utilization
This chapter reviews the study and development of biological, enzymatic and bio-molecular systems for carbon dioxide capture and further sequestration or even utilization. Regardless of the interest on the use of the captured CO2 as C1 synthon on the manufacture of added-value compounds, there is a tremendous unbalance between the requirements of the contemporary society (leading to a massive production of carbon dioxide) and the framework of commercialization of the products from CO2 utilization. In this context, viable options are storage as a solid in the form of calcium or magnesium carbonate and conversion into other energetic frameworks. In addition, it is important to highlight that the conventional energy resources are progressively being replaced by renewable resources. While the change in energetic paradigm is not accomplished, systems that capture and convert carbon dioxide are highly sought. To this end, bio-inspired systems will be presented, starting from the use of compounds from the chiral pool, such as amino acids, saccharides and related bio-polymers, involved in the physical and chemical capture, sequestration and/or utilization of CO2. Additionally, enzymatic systems are presented in the context of sequestration of CO2 in the form of solid carbonates or even utilization of this C1 synthon in the preparation of fuels and commodity chemicals. Carbonic anhydrase is by far the most studied enzyme, as it catalyses the inter-conversion between CO2 and hydrogencarbonate in an effective mode. The biological option comprises the utilization of methanogens, acetogens and other organisms leading to the formation of added-value compounds. Most of the described systems are based on microbial electro-synthesis model and microbial carbon-capture cell prototypes
Origin of the unusually low nitrogen abundances in young populations of the Large Magellanic Cloud
It is a longstanding problem that HII regions and very young stellar
populations in the Large Magellanic Cloud (LMC) have the nitrogen abundances
([N/H]) by a factor of ~7 lower than the solar value. We here discuss a new
scenario in which the observed unusually low nitrogen abundances can be closely
associated with recent collision and subsequent accretion of HI high velocity
clouds (HVCs) that surround the Galaxy and have low nitrogen abundances. We
show that if the observed low [N/H] is limited to very young stars with ages
less than ~10^7 yr, then the collision/accretion rate of the HVCs onto the LMC
needs to be ~ 0.2 M_sun/yr (corresponding to the total HVC mass of 10^6-10^7
M_sun) to dilute the original interstellar medium (ISM) before star formation.
The required accretion rate means that even if the typical mass of HVCs
accreted onto the LMC is ~ 10^7 M_sun, the Galaxy needs to have ~2500 massive
HVCs within the LMC's orbital radius with respect to the Galactic center. The
required rather large number of massive HVCs drives us to suggest that the HVCs
are not likely to efficiently dilute the ISM of the LMC and consequently lower
the [N/H]. We thus suggest the transfer of gas with low [N/H] from the Small
Magellanic Cloud (SMC) to the LMC as a promising scenario that can explain the
observed low [N/H].Comment: 24pages, 6 figures, accepted in Ap
Chemoinformatic Approaches To Predict the Viscosities of Ionic Liquids and Ionic Liquid-Containing Systems
UID/QUI/50006/2019.Modelling, predicting, and understanding the factors influencing the viscosities of ionic liquids and related mixtures are sequentially checked in this work. The molecular maps of atom-level properties (MOLMAP codification system) is adapted for a straightforward inclusion of ionic liquids and mixtures containing ionic liquids. Random Forest models have been tested in this context and an optimal model was selected. The interpretability of the selected Random Forest model is highlighted with selected structural features that might contribute to identify low viscosities. The constructed model is able to recognize the influence of different structural variables, temperature, and pressure for a correct classification of the different systems. The codification and interpretation systems are highlighted in this work.authorsversionpublishe
Effects of therapeutic exercises in patients with lung cancer. A scoping review
Financiado para publicaciĂłn en acceso aberto: Universidade de Vigo/CISUGIntroduction: Lung cancer is one of the most common malignancies worldwide and the leading cause of cancer-related death. Smoking is one of the main risk factors associated with this cancer. Treatment will depend on the form of cancer and its stage, existing many therapeutic possibilities. In this regard, therapeutic exercise plays an important role in lung cancer care, as well as the pulmonary rehabilitation and respiratory physical therapy.
Purpose: To review the current scientific literature about the effects of therapeutic exercise in lung cancer.
Method: A search was carried out in CINAHL, MEDLINE, PubMed, Scopus y Web of Science using de terms âExercise Therapyâ and âLung Neoplasmsâ. 141 studies were obtained, but only 19 were selected by adjusting to the inclusion and exclusion criteria. 10 of them were randomized controlled trials with a Jadad score between 2 and 3.
Results: These works performed a large variety of interventions based on therapeutic exercise, classified in preoperative, postoperative, during treatment, post treatment and combination. Most focused on aerobic exercise, muscle strength and respiratory exercises. Conclusion: therapeutic exercise seems to be positive and obtain significant improvements in patients with lung cancer, regardless the moment of intervention and the type of exercise performed
CO 2 âŻ+âŻMethanolâŻ+âŻGlycerol: Multiphase behaviour
The phase behaviour of the system CO2âŻ+âŻmethanolâŻ+âŻglycerol has been studied at low concentrations of this tri-alcohol. The synthetic method was implemented in a visual sapphire cell. New phase diagrams were obtained at temperatures of 313.15 and 333.15âŻK. Different methanol/glycerol molar ratios of 113, 50 and 30 were considered and its influence on phase behaviour accounted for. Pressures were varied from 6.03 to 11.44âŻMPa. A specific experiment is reported, starting from an initial volume of 4âŻmL of liquid mixture methanolâŻ+âŻglycerol (methanol/glycerol molar ratio 30), where, with a stepwise addition of CO2, diverse fluid phase phenomena were detected, such as VLE, Critical Point, VLLE, VLLLE, LLE and LE
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