108 research outputs found

    Determinantes de la demanda eléctrica residencial en Argentina : Un análisis comparado entre 2013 y 2018 y una aproximación al rol de la eficiencia energética como un camino alternativo de política energética

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    El presente trabajo analiza los determinantes de la demanda eléctrica residencial de Argentina para los períodos 2012/3 y 2017/8 en base a microdatos de la Encuesta Nacional de Hogares para dichos años. Se identifican como relevantes las características estructurales del hogar (acceso a gas natural, estructura de las paredes, si habitan en casas o departamentos), las sociodemográficas de sus habitantes (cantidad de miembros, edad y género, el ingreso que perciben, el nivel educativo, en qué región del país residen, entre otros), y los precios al que acceden a la electricidad. Asimismo, se postula al equipamiento del hogar (electro/gasodomésticos) como una variable cada vez más preponderante al momento de estudiar el patrón de consumo de las familias. La metodología utilizada estima la función de demanda residencial a través de MCO y de regresiones cuantílicas reconociendo que el comportamiento de los hogares y por ende sus determinantes, cambian en función del segmento de consumo en el que se encuentren. Los principales resultados indican que la elasticidad precio e ingreso en el corto plazo permanecen relativamente estables entre los períodos analizados y son menores a la unidad, definiendo a la electricidad como un bien necesario. Asimismo, ambas se incrementan en los hogares más pobres, señalando que el consumo de energía está restringido en función de su nivel de ingreso y que los ajustes tarifarios tienen un impacto de mayor magnitud. Por su parte, el análisis del rol del equipamiento permite focalizar programas de eficiencia energética en función de los usos que los hogares realizan de la energía. Así, es factible diferenciar qué tipo de política es acorde según qué población y segmento de consumo se trate; definir si existen regiones o deciles de ingreso con mayor potencial de ahorro energético y por último, identificar qué aparatos tienen mayor incidencia en el consumo de los hogares. La delicada situación del sector energético actual requiere repensar las herramientas tradicionalmente utilizadas como la administración de las tarifas, políticas de incentivo a la oferta interna de energía y subsidios al consumo, e incorporar a la demanda de energía residencial como un componente más de la ecuación. Conocer cuáles son sus determinantes y cómo las decisiones de consumo cambian en función de las características señaladas permitirá diagramar políticas energéticas acordes que logren encauzar un sendero de desarrollo del sistema energético nacional seguro y sostenible en el tiempo.Fil: Balestro, Florencia E.. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Buenos Aires, Argentina

    Using a quantum dot as a high-frequency shot noise detector

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    We present the experimental realization of a Quantum Dot (QD) operating as a high-frequency noise detector. Current fluctuations produced in a nearby Quantum Point Contact (QPC) ionize the QD and induce transport through excited states. The resulting transient current through the QD represents our detector signal. We investigate its dependence on the QPC transmission and voltage bias. We observe and explain a quantum threshold feature and a saturation in the detector signal. This experimental and theoretical study is relevant in understanding the backaction of a QPC used as a charge detector.Comment: 4 pages, 4 figures, accepted for publication in Physical Review Letter

    Seismotectonic investigations in the inner Cottian Alps (Italian Western Alps): An integrated approach

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    This work integrates the results of recent geological–structural studies with new seismological data for the inner Cottian Alps to investigate the connection between faults and seismicity. The major post-metamorphic tectonic feature of this sector is represented by a N–S structure, named Lis–Trana Deformation Zone (LTZ). Since the Late Oligocene, this structure accommodated right-lateral (Late Oligocene–Early Miocene) and subsequently normal (post-Early Miocene) displacements. In the Pleistocene, the activity of the LTZ seems to have caused the development of lacustrine basins inside the valleys that drain this sector of Western Alps. The present-day seismicity joins the northern part of the LTZ and, southwards, other minor sub-parallel structures. In transversal cross-section hypocentres highlight steep surfaces. Focal mechanisms calculated along this structure show both extensional and strike–slip solutions, mostly with one roughly N–S striking nodal plane. Both sub-horizontal (with NE–SW to ENE–WSW trend) and steeply dipping P axes with N–S to NW–SE sub-horizontal T axes are observed. Even if clear evidence of Quaternary tectonic activity in the area is missing, on the basis of the available seismological and geological data we propose that in the inner Northern Cottian Alps the present-day seismic activity may be connected to the LTZ, interpreted as minor sub-parallel fault strand of the Canavese Line. The kinematics of this structure is consistent with the focal mechanisms calculated in this area. Structural and seismological data indicate that LTZ is active under a bulk dextral–transtensive regime since the late Oligocene in the inner Cottian Alps, in agreement with the data published for the adjacent domain of the chain.Published1-163.3. Geodinamica e struttura dell'interno della TerraJCR Journalrestricte

    Thoracic involvement in systemic autoimmune rheumatic diseases: pathogenesis and management.

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    Thoracic involvement is one of the main determinants of morbidity and mortality in patients with autoimmune rheumatic diseases (ARDs), with different prevalence and manifestations according to the underlying disease. Interstitial lung disease (ILD) is the most common pulmonary complication, particularly in patients with systemic sclerosis (SSc), idiopathic inflammatory myopathies (IIMs) and rheumatoid arthritis (RA). Other thoracic manifestations include pulmonary arterial hypertension (PAH), mostly in patients with SSc, airway disease, mainly in RA, and pleural involvement, which is common in systemic lupus erythematosus and RA, but rare in other ARDs.In this review, we summarize and critically discuss the current knowledge on thoracic involvement in ARDs, with emphasis on disease pathogenesis and management. Immunosuppression is the mainstay of therapy, particularly for ARDs-ILD, but it should be reserved to patients with clinically significant disease or at risk of progressive disease. Therefore, a thorough, multidisciplinary assessment to determine disease activity and degree of impairment is required to optimize patient management. Nevertheless, the management of thoracic involvement-particularly ILD-is challenging due to the heterogeneity of disease pathogenesis, the variety of patterns of interstitial pneumonia and the paucity of randomized controlled clinical trials of pharmacological intervention. Further studies are needed to better understand the pathogenesis of these conditions, which in turn is instrumental to the development of more efficacious therapies

    Superposed sedimentary and tectonic block-in-matrix fabrics in a subducted serpentinite m\ue9lange (High-pressure zermatt saas ophiolite, western alps)

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    The primary stratigraphic fabric of a chaotic rock unit in the Zermatt Saas ophiolite of the Western Alps was reworked by a polyphase Alpine tectonic deformation. Multiscalar structural criteria demonstrate that this unit was deformed by two ductile subduction-related phases followed by brittle-ductile then brittle deformation. Deformation partitioning operated at various scales, leaving relatively unstrained rock domains preserving internal texture, organization, and composition. During subduction, ductile deformation involved stretching, boudinage, and simultaneous folding of the primary stratigraphic succession. This deformation is particularly well-documented in alternating layers showing contrasting deformation style, such as carbonate-rich rocks and turbiditic serpentinite metasandstones. During collision and exhumation, deformation enhanced the boudinaged horizons and blocks, giving rise to spherical to lozenge-shaped blocks embedded in a carbonate-rich matrix. Structural criteria allow the recognition of two main domains within the chaotic rock unit, one attributable to original broken formations reflecting turbiditic sedimentation, the other ascribable to an original sedimentary m\ue9lange. The envisaged geodynamic setting for the formation of the protoliths is the Jurassic Ligurian-Piedmont ocean basin floored by mostly serpentinized peridotites, intensely tectonized by extensional faults that triggered mass transport processes and turbiditic sedimentation

    Subclinical liver fibrosis in patients with idiopathic 1 pulmonary fibrosis.

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    Background - Data on the presence of subclinical fibrosis across multiple organs in patients with idiopathic lung fibrosis (IPF) are lacking. Our study aimed at investigating through hepatic transient elastography (HTE) the prevalence and clinical impact of subclinical liver fibrosis in a cohort of patients with IPF. Methods - Patients referred to the Centre for Rare Lung Disease of the University Hospital of Modena (Italy) from March 2012 to February 2013with established diagnosis of IPF and without a documented history of liver diseases were consecutively enrolled and underwent HTE. Based on hepatic stiffness status as assessed through METAVIR score patients were categorized as \u201c with liver fibrosis \u201d (corresponding to a METAVIR score of F1-F4) and \u201c without liver fibrosis\u201d (METAVIR F0). Potential predictors of liver fibrosis were investigated through logistic regression model among clinical and serological variables. The overall survival (OS) was assessed according to liver fibrosis and multivariate Cox regression analysis was used to identify independent predictors. Results - In 13 out of 37 patients (35%) with IPF a certain degree of liver fibrosis was documented.No correlation was found between liver stiffness and clinical-functional parameters. OS was lower in patients \u2018 with liver fibrosis\u2019 than in patients \u2018 without liver fibrosis\u2019 (median months 33[23-55] vs. 63[26-94], p=0.038). Patients \u2018 with liver fibrosis\u2019 presented a higher risk of death at seven years as compared to patients \u2018without liver fibrosis\u2019 (HR=2.6, 95%CI[1.003\u20136.7],p= 0.049). Higher level of AST to platelet ratio Index (APRI)was an independent predictor of survival (HR=4.52 95%CI[1.3\u201315.6], p=0.02). Conclusions - In our cohort, more than one third of IPF patients had concomitant subclinical liver fibrosis that negatively affected OS. These preliminary claims further investigation aimed at clarifying the mechanisms beyond multiorgan fibrosis and its clinical implication in patients with IPF

    Patient-reported outcomes and patient-reported outcome measures in interstitial lung disease: Where to go from here?

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    Patient-reported outcome measures (PROMs), tools to assess patient self-report of health status, are now increasingly used in research, care and policymaking. While there are two well-developed disease-specific PROMs for interstitial lung diseases (ILD) and idiopathic pulmonary fibrosis (IPF), many unmet and urgent needs remain. In December 2019, 64 international ILD experts convened in Erice, Italy to deliberate on many topics, including PROMs in ILD. This review summarises the history of PROMs in ILD, shortcomings of the existing tools, challenges of development, validation and implementation of their use in clinical trials, and the discussion held during the meeting. Development of disease-specific PROMs for ILD including IPF with robust methodology and validation in concordance with guidance from regulatory authorities have increased user confidence in PROMs. Minimal clinically important difference for bidirectional changes may need to be developed. Cross-cultural validation and linguistic adaptations are necessary in addition to robust psychometric properties for effective PROM use in multinational clinical trials. PROM burden of use should be reduced through appropriate use of digital technologies and computerised adaptive testing. Active patient engagement in all stages from development, testing, choosing and implementation of PROMs can help improve probability of success and further growth

    First experimental evidence of one-dimensional plasma modes in superconducting thin wires

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    We have studied niobium superconducting thin wires deposited onto a SrTiO3_{3} substrate. By measuring the reflection coefficient of the wires, resonances are observed in the superconducting state in the 130 MHz to 4 GHz range. They are interpreted as standing wave resonances of one-dimensional plasma modes propagating along the superconducting wire. The experimental dispersion law, ω\omega versus qq, presents a linear dependence over the entire wave vector range. The modes are softened as the temperature increases close the superconducting transition temperature. Very good agreement are observed between our data and the dispersion relation predicted by Kulik and Mooij and Sch\"on.Comment: Submitted to Physical review Letter
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