1,032 research outputs found

    Union Games: Technological Unemployment

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    Given a production economy, we define a trade union game by considering strategic behavior on factor supplies. We refer to the Nash equilibria of this game as trade union equilibria. First we analyze situations under which unemployment of factors are supported as trade union equilibria. The degree of unemployment depends on technological conditions. In this line, we suggest a source of unemployment which differs from the usual sources provided in the related literature. Then, we state a limit result which shows that when the market power of trade unions decreases the corresponding sequence of trade union equilibria converges to the walrasian equilibrium, that is, to full employment of factors.Trade Union Games, unemployment, walrasian equilibrium, manipulability.

    Identifying the neural mechanisms of perceptual decision-making in a rat auditory task

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    Treballs Finals de Grau d'Enginyeria Biomèdica. Facultat de Medicina i Ciències de la Salut. Universitat de Barcelona. Curs: 2020-2021. Directors: Jaime de la Rocha and Genís Prat. Tutor: Agustín Gutiérrez GálvezPerceptual decision-making involves accumulation of sensory information over time. The classical view indicates that sensory neurons first transform the physical stimulus into evidence, and then the decision making areas of the brain use this evidence to make a categorical choice. Here, we show that this process is not optimal. In general, rats do not equally weigh the stimulus and they underweight extreme stimuli values. These results indicate that there must be a non-linearity in the stimulus transformation into evidence or that the accumulation of evidence is not perfect. To differentiate which are the underlying mechanisms that are causing these behaviours, we fitted an extended neurobiological model which was composed of a stimulus to evidence and a decision module. Using model comparison methods, we were able to identify that a non-linear stimulus to evidence transformation is relevant to explain the psychophysical kernels of the experimental task, but that time adaptation of the sensory neurons does not have an impact in this case. We also found that, at least for a subset of rats, the non-linear dynamics in the decision module explains the experimental data better than a linear perfect integration model. Our work shows that model fitting is a powerful tool to investigate different brain mechanisms and that non-linear dynamics could be important not only during the accumulation of evidence but also during the stimulus to evidence transformation

    Training-induced gene expression plasticity in cardiac function and neural regulation for ultra-trail runners

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    This study aims to assess the gene regulatory response from a group of 16 athletes and to observe the plasticity induced by their training regime on the gene expression response after their participation in an 82km race. Blood samples for differential gene expression (DGE) were collected before and after this effort from two groups of runners with different training regimes: elite and active. Analyses only focused on genes annotated as related to cardiac function (CF) and neural regulation (NR) from the KEGG PATHWAY Database. Thus, 13 pathways were considered accounting for a total of 629 genes. Training regime modulated the response to exercise based on a list of 18 ranked genes with significant DGE for elite runners while remained statistically insignificant for active athletes. UQCR11, COX7C and COX4I1 genes, related to mitochondrial respiratory chain, were down-regulated which may indicate mitochondrial function impairment in cardiac muscle. Increased expression levels were obtained for PIK3R2, PLCG2, IRAK3 genes from the positive signaling cascades of neurotrophins pathway, which may reveal an improved heart rate control thanks to a better cardiac sympathetic innervation.Postprint (author's final draft

    Combined use of the GGSFT data base and on Board Marine Collected Data to Model the Moho Beneath the Powell Basin, Antarctica

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    The Powell Basin is a small oceanic basin located at the NE end of the Antarctic Peninsula developed during the Early Miocene and mostly surrounded by the continental crusts of the South Orkney Microcontinent, South Scotia Ridge and Antarctic Peninsula margins. Gravity data from the SCAN 97 cruise obtained with the R/V Hespérides and data from the Global Gravity Grid and Sea Floor Topography (GGSFT) database (Sandwell and Smith, 1997) are used to determine the 3D geometry of the crustal-mantle interface (CMI) by numerical inversion methods. Water layer contribution and sedimentary effects were eliminated from the Free Air anomaly to obtain the total anomaly. Sedimentary effects were obtained from the analysis of existing and new SCAN 97 multichannel seismic profiles (MCS). The regional anomaly was obtained after spectral and filtering processes. The smooth 3D geometry of the crustal mantle interface obtained after inversion of the regional anomaly shows an increase in the thickness of the crust towards the continental margins and a NW-SE oriented axis of symmetry coinciding with the position of an older oceanic spreading axis. This interface shows a moderate uplift towards the western part and depicts two main uplifts to the northern and eastern sectors

    Ammonium enhances resistance to salinity stress in citrus plants

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    In this work, we demonstrate that NH4+ nutrition in citrange Carrizo plants acts as an inducer of resistance against salinity conditions. We investigated its mode of action and provide evidence that NH4+ confers resistance by priming abscisic acid and polyamines, and enhances H2O2 and proline basal content. Moreover, we observed reduced Cl− uptake as well as enhanced PHGPx expression after salt stress. Control and N-NH4+ plants showed optimal growth. However, N-NH4+ plants displayed greater dry weight and total lateral roots than control plants, but these differences were not observed for primary root length. Our results revealed that N-NH4+ treatment induces a similar phenotypical response to the recent stress-induced morphogenetic response (SIMRs). The hypothesis is that N-NH4+ treatment triggers mild chronic stress in citrange Carrizo plants, which might explain the SIMR observed. Moreover, we observed modulators of stress signaling, such as H2O2 in N-NH4+ plants, which could acts as an intermediary between stress and the development of the SIMR phenotype. This observation suggests that NH4+ treatments induce a mild stress condition that primes the citrange Carrizo defense response by stress imprinting and confers protection against subsequent salt stress

    Detection of gamma rays of likely jet origin in Cygnus X-1

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    Aims: Probe the high-energy (>>60 MeV) emission from the black hole X-ray binary system, Cygnus X-1, and investigate its origin. Methods: We analysed 7.5 yr of data by Fermi/LAT with the latest PASS8 software version. Results: We report the detection of a signal at \sim8 σ\sigma statistical significance spatially coincident with Cygnus X-1 and a luminosity above 60 MeV of 5.5×\times1033^{33} erg s1^{-1}. The signal is correlated with the hard X-ray flux: the source is observed at high energies only during the hard X-ray spectral state, when the source is known to display persistent, relativistic radio emitting jets. The energy spectrum, extending up to \sim20 GeV without any sign of spectral break, is well fitted by a power-law function with a photon index of 2.3±\pm0.2. There is a hint of orbital flux variability, with high-energy emission mostly coming around the superior conjunction. Conclusions: We detected GeV emission from Cygnus X-1 and probed that the emission is most likely associated with the relativistic jets. The evidence of flux orbital variability points to the anisotropic inverse Compton on stellar photons as the mechanism at work, thus constraining the emission region to a distance 1011101310^{11}-10^{13} cm from the black hole.Comment: accepted A\&A (9 pages and 7 figures

    Patients’ opinions about knowing their risk for depression and what to do about it: The PredictD-Qualitative study

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    Background: The predictD study developed and validated a risk algorithm for predicting the onset of major depression in primary care. We aimed to explore the opinion of patients about knowing their risk for depression and the values and criteria upon which these opinions are based. Methods: A maximum variation sample of patients was taken, stratified by city, age, gender, immigrant status, socioeconomic status and lifetime depression. The study participants were 52 patients belonging to 13 urban health centres in seven different cities around Spain. Seven Focus Groups (FGs) were given held with primary care patients, one for each of the seven participating cities. Results: The results showed that patients generally welcomed knowing their risk for depression. Furthermore, in light of available evidence several patients proposed potential changes in their lifestyles to prevent depression. Patients generally preferred to ask their General Practitioners (GPs) for advice, though mental health specialists were also mentioned. They suggested that GPs undertake interventions tailored to each patient, from a ‘‘patient-centred’’ approach, with certain communication skills, and giving advice to help patients cope with the knowledge that they are at risk of becoming depressed. Conclusions: Patients are pleased to be informed about their risk for depression. We detected certain beliefs, attitudes, values, expectations and behaviour among the patients that were potentially useful for future primary prevention programmes on depression.Junta de Andalucía 2008/0195Gobierno Vasco 2008/111021Spanish Network of Primary Care Research (redIAPP) RD06/0018Salud Mental, Servicios y Atención Primaria (SAMSERAP

    A deep learning approach to space weather proxy forecasting for orbital prediction

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    The effect of atmospheric drag on spacecraft dynamics is considered one of the predominant sources of uncertainty in Low Earth Orbit. These effects are characterised in part by the atmospheric density, a quantity highly correlated to space weather. Current atmosphere models typically account for this through proxy indices such as the F10.7, but with variations in solar radio flux forecasts leading to significant orbit differences over just a few days, prediction of these quantities is a limiting factor in the accurate estimation of future drag conditions, and consequently orbital prediction. This has fundamental implications both in the short term, in the day-to-day management of operational spacecraft, and in the mid-to-long term, in determining satellite orbital lifetime. In this work, a novel deep residual architecture for univariate time series forecasting, N-BEATS, is employed for the prediction of the F10.7 solar proxy on the days-ahead timescales relevant to space operations. This untailored, pure deep learning approach has recently achieved state-of-the-art performance in time series forecasting competitions, outperforming well-established statistical, as well as statistical hybrid models, across a range of domains. The approach was found to be effective in single point forecasting up to 27-days ahead, and was additionally extended to produce forecast uncertainty estimates using deep ensembles. These forecasts were then compared to a persistence baseline and two operationally available forecasts: one statistical (provided by BGS, ESA), and one multi-flux neural network (by CLS, CNES). It was found that the N-BEATS model systematically outperformed the baseline and statistical approaches, and achieved an improved or similar performance to the multi-flux neural network approach despite only learning from a single variabl

    Inflammation and metabolic dysregulation in diabetic cardiomyopathy

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    Podeu consultar el llibre complet a: http://hdl.handle.net/2445/67430Diabetic cardiomyopathy is characterized by structural and functional alterations in the heart muscle of people with diabetes that finally lead to heart failure. Metabolic disturbances characterized by increased lipid oxidation, intramyocardial triglyceride accumulation and reduced glucose utilization have all been involved in the pathogenesis of diabetic cardiomyopathy. On the other hand, evidences arisen in the recent years point to a potential link between chronic low-grade inflammation in the heart and metabolic dysregulation. Interestingly, the progression of heart failure and cardiac hypertrophy usually entails the activation of pro-inflammatory pathways. Therefore, in this chapter we summarize novel insights into the crosstalk between inflammatory processes and metabolic dysregulation in the failing heart during diabetes
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