5,401 research outputs found

    3D Radiation hydrodynamics of a dynamical torus

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    We have developed a new dynamical model of the torus region in active galactic nucleus (AGN), using a three-dimensional radiation hydrodynamics algorithm. These new simulations have the specific aim to explore the role of radiatively-driven outflows, which is hotly debated in current literature as a possible explanation for the observed infrared emission from the polar regions of AGN. In this first paper, we only consider radiative effects induced by the primary radiation from the AGN. The simulations generate a disk & outflow structure that qualitatively agrees with observations, although the outflow is radial rather than polar, likely due to the lack of radiation pressure from hot dust. We find cut-offs between the wind and disk at gas temperatures of 1000 K and dust temperatures of 100 K, producing kinematic signatures that can be used for interpretation of high resolution infrared observations. We also produce line emission maps to aid in the interpretation of recent ALMA observations and future JWST observations. We investigate a number of simulation parameters, and find that the anisotropy of the radiation field is equally important to the Eddington factor, despite the anisotropy often being assumed to have a single sometimes arbitrary form in many previous works. We also find that supernovae can have a small but significant impact, but only at extremely high star formation rates.Comment: 2nd revision, Accepted in Ap

    Investing cash transfers to raise long term living standards

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    The authors test whether poor households use cash transfers to invest in income generating activities that they otherwise would not have been able to do. Using data from a controlled randomized experiment, they find that transfers from the Oportunidades program to households in rural Mexico resulted in increased investment in micro-enterprise and agricultural activities. For each peso transferred, beneficiary households used 88 cents to purchase consumption goods and services, and invested the rest. The investments improved the household's ability to generate income with an estimated rate of return of 17.55 percent, suggesting that these households were both liquidity and credit constrained. By investing transfers to raise income, beneficiary households were able to increase their consumption by 34 percent after five and a half years in the program. The results suggest that cash transfers to the poor may raise long-term living standards, which are maintained after program benefits end.Economic Theory&Research,Small Area Estimation Poverty Mapping,Municipal Housing and Land,Land and Real Estate Development,Real Estate Development

    Role of wnt/beta-catenin signaling in ovarian tumour growth and angiogenesis. A crosstalk with Notch system

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    Wnt/β-catenin and Notch are highly conserved pathways that regulate a diversity of cell processes, including proliferation, apoptosis and differentiation. We analyzed the role of both systems in ovarian cancer using specific inhibitors. For this purpose we performed three in vivo experiments. A human ovarian adenocarcinoma cell line (IGROV-1) was subcutaneously injected in 6-8 weeks-old female nude mice. Once the tumours were palpable, we injected the inhibitors: the first and second experiments were carried out using Wnt/β-catenin inhibitors (XAV939: 2.5, 5 mg/kg; ICG-001: 5 and10 mg/kg). The third experiment was a combination of ICG-001 (5mg/kg) and DAPT (5 mg/kg), a Notch inhibitor. Mice were injected every two days three times and they were euthanized 3 days after the last injection. Our results showed a significant decrease in tumour size when mice were treated either with XAV939 or with ICG-001. When compared with tumours from non-treated animals, both experiments showed a significant decrease in cell proliferation (KI67) and a decrease in the endothelial and periendothelial cell area stained with CD31 and α-Smooth-muscle-actin, respectively. When mice were treated with XAV939, a significant decrease in VEGF levels and Angiopoietin 1/2 was observed. Regarding the experiment with the combination of inhibitors, there was a significant decrease in tumour size and a decline in tumour cell proliferation (KI67). Both inhibitors administered simultaneously produced a decrease in cell proliferation at the same extent as individually administrated. In conclusion, we demonstrate a clear involvement of Wnt/β-catenin in ovarian tumour growth and angiognesis. We suggest an interaction of this pathway with Notch system.Fil: Bocchicchio, Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Tesone, Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Irusta, Griselda. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaXX Jornadas anuales de la Sociedad Argentina de Biología. XVII Jornadas de la Sociedad Uruguaya de BiocienciasBuenos AiresArgentinaSociedad Argentina de BiologíaSociedad Uruguaya de Biologí

    Years of service, self-efficacy, stress and burnout among Polish firefighters

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    Objectives: The aim of the research was to analyze the impact of selected factors: years of service, the number of interventions, self-efficacy and stress, on occupational burnout. It was hypothesized that firefighters with more years of service and a bigger number of interventions would be characterized by higher perceived stress and burnout, and that self-efficacy would have an impact on reducing the level of perceived stress and burnout. Material and Methods: The participants were firefighters (N = 576) from 12 Polish voivodeships, aged 20-58 years, with different seniority: up to 3, 4-8, 9-15 or >15 years of service. The following research tools were used: the Link Burnout Questionnaire, the 10-item Perceived Stress Scale, the Generalized Self-Efficacy Scale, and an independent questionnaire to gather additional information. A correlation between particular variables was carried out; the Kruskal-Wallis test was performed together with a post-hoc analysis to examine differences in the severity of individual variables depending on seniority, followed by a path analysis studied together with the identification of direct and indirect impacts. Results: The number of interventions did not affect the severity of experienced stress or any of the aspects of burnout. Work experience directly influenced the level of perceived stress (β = 0.219), disillusion (β = 0.076), and relationship deterioration (β = -0.156). The generalized sense of self-efficacy was found to impact both on reducing the sense of stress (β = -0.418) and on all 4 aspects of professional burnout: psychophysical exhaustion (β = -0.181), relationship deterioration (β = -0.16), the sense of professional inefficacy (β = -0.275) and disillusion (β = -0.143). Conclusions: The results have shown that: 1) the number of interventions does not affect the severity of experienced stress or particular aspects of burnout; 2) years of service increase the severity of experienced stress and occupational burnout; 3) self-efficacy has an impact both on reducing the sense of stress and on all aspects of burnout

    Airport Infrastructure Development: A Comprehensive Impact Review

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    Purpose: Airports play a vital role in global transportation networks, facilitating the movement of people, goods, and services, while also serving as catalysts for economic growth; however, it also has an environmental and social impact that needs to be analyzed. This literature review aims to address knowledge gaps concerning the influence of airport infrastructure on economic, socio-economic, environmental, and sustainability factors.   Theoretical Framework: Adopts a multidisciplinary approach, blending economic, environmental, and societal theories of impact.   Design/Methodology/Approach: The SPAR-4-SLR protocol was utilized, analyzing a comprehensive set of 32 scientific papers categorized within the previously mentioned areas.   Findings: Several areas were identified that require further investigation, including strategies to mitigate the environmental impact of airports, assessment of socio-economic implications on local communities, and ensuring the long-term sustainability of airport operations.   Originality/Value: Going beyond the conventional focus, the study provides original insights that extend the understanding of direct economic benefits, environmental consequences, and societal impacts. By synthesizing diverse perspectives, this research contributes significantly to the discourse on airport development, making it an invaluable resource for policymakers, industry stakeholders, and researchers

    Many Facets of Strangeness Nuclear Physics with Stored Antiprotons

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    Stored antiprotons beams in the GeV range represent a unparalleled factory for hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of strange hadronic systems with unprecedented precision. The behavior of hyperons and -- for the first time -- of antihyperons in nuclear systems can be studied under well controlled conditions. The exclusive production of ΛΛˉ\Lambda\bar{\Lambda} and ΣΛˉ\Sigma^-\bar{\Lambda} pairs in antiproton-nucleus interactions probe the neutron and proton distribution in the nuclear periphery and will help to sample the neutron skin. For the first time, high resolution γ\gamma-spectroscopy of doubly strange nuclei will be performed, thus complementing measurements of ground state decays of double hypernuclei with mesons beams at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Ξ\Xi-atoms are feasible and even the production of Ω\Omega^--atoms will be within reach. The latter might open the door to the s|s|=3 world in strangeness nuclear physics, by the study of the hadronic Ω\Omega^--nucleus interaction and the very first measurement of a spectroscopic quadrupole moment of a baryon which will be a benchmark test for our understanding of hadron structure.Comment: Proceddings of HYP201

    Dissimilarity functions for rank-invariant hierarchical clustering of continuous variables

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    A theoretical framework is presented for a (copula-based) notion of dissimilarity between continuous random vectors and its main properties are studied. The proposed dissimilarity assigns the smallest value to a pair of random vectors that are comonotonic. Various properties of this dissimilarity are studied, with special attention to those that are prone to the hierarchical agglomerative methods, such as reducibility. Some insights are provided for the use of such a measure in clustering algorithms and a simulation study is presented. Real case studies illustrate the main features of the whole methodology.Comment: 38 pages, 10 figures, 7 table

    New records of hypocrealean fungi infecting aphids and whiteflies: Pathogenicity against Myzus persicae and interaction with its predator Eriopis connexa

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    Occurrence of hypocrealean entomopathogenic fungi in Argentina is reported. Bioassays were performed to evaluate their pathogenicity against Myzus persicae and Eriopis connexa. The findings underscore the importance of preserving these fungi and of investigating their potential for vector control.Fil: Scorsetti, Ana Clara. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Botánica Spegazzini; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Pelizza, Sebastian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Botánica Spegazzini; ArgentinaFil: Cabello, Marta Noemí. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Botánica Spegazzini; Argentin
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