539 research outputs found
Earthquake hazard characterization by using entropy: application to northern Chilean earthquakes
The mechanical description of the seismic cycle has an energetic analogy in terms of statistical physics and the second law of
thermodynamics. In this context, an earthquake can be considered a phase
transition, where continuous reorganization of stresses and forces reflects
an evolution from equilibrium to non-equilibrium states, and we can use this
analogy to characterize the earthquake hazard of a region. In this study, we used 8 years (2007–2014) of high-quality Integrated Plate Boundary
Observatory Chile (IPOC) seismic data for > 100 000 earthquakes
in northern Chile to test the theory that Shannon entropy, H, is an indicator of the equilibrium state of a seismically active region. We confirmed increasing H reflects the irreversible transition of a system and is linked to the occurrence of large earthquakes. Using variation in H, we could detect major earthquakes and their foreshocks and aftershocks, including the 2007 Mw 7.8 Tocopilla earthquake, the 2014 Mw 8.1 Iquique earthquake,
and the 2010 and 2011 Calama earthquakes (Mw 6.6 and 6.8,
respectively). Moreover, we identified possible periodic seismic behaviour
between 80 and 160 km depth.</p
Patterns of diversification in the high Andean Ponderacris grasshoppers (Orthoptera: Acrididae: Melanoplinae)
Fil: Pocco, Martina E.. División Entomología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Posadas, Paula. Laboratorio de Sistemática y Biología Evolutiva (LASBE). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Lange, Carlos Ernesto. Centro de Estudios en Parasitología y Vectores (CEPAVE). Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Cigliano, María Marta. División Entomología. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin
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Loss of testosterone impairs anti-tumor neutrophil function.
In men, the incidence of melanoma rises rapidly after age 50, and nearly two thirds of melanoma deaths are male. The immune system is known to play a key role in controlling the growth and spread of malignancies, but whether age- and sex-dependent changes in immune cell function account for this effect remains unknown. Here, we show that in castrated male mice, neutrophil maturation and function are impaired, leading to elevated metastatic burden in two models of melanoma. Replacement of testosterone effectively normalized the tumor burden in castrated male mice. Further, the aberrant neutrophil phenotype was also observed in prostate cancer patients receiving androgen deprivation therapy, highlighting the evolutionary conservation and clinical relevance of the phenotype. Taken together, these results provide a better understanding of the role of androgen signaling in neutrophil function and the impact of this biology on immune control of malignancies
Patch Antenna Based on Metamaterials for a RFID Transponder
In this paper a self-diplexed antenna is proposed for a RFID transponder application. The development cycle is divided into two stages: antenna design and filters design. The antenna is based on a square microstrip patch filled with metamaterial structures. The inclusion of these structures allows simultaneous operation over several frequencies, which can be arbitrarily chosen. The antenna working frequencies are chosen to be 2.45 GHz (receiver) and 1.45 GHz (transmitter). In addition, the antenna is fed through two orthogonal coupled microstrip lines, what provides higher isolation between both ports. Some filters based on metamaterial particles are coupled or connected to the antenna feeding microstrip lines to avoid undesired interferences. This approach avoids using of an external filter or diplexer, providing larger size reduction and a compact self-diplexed antenna
Tsallis Entropy and Mutability to Characterize Seismic Sequences: The Case of 2007–2014 Northern Chile Earthquakes
Partial support from the following two Chilean sources is acknowledged: Fondecyt under contract 1230055, Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia (Chile) through the Center for Development of Nanoscience and Nanotechnology (CEDENNA) under contract AFB220001. This research has been partially supported by the Agencia Estatal de Investigación (grant no. PID2021-124701NBC21 y C22); the Universidad de Almería (grant no. FEDER/UAL Project UAL2020-RNM-B1980); the Consejería de Universidad, Investigación e Innovación, Junta de Andalucía (grant no. RNM104). PPITUAL, Junta de Andalucía-FEDER 2021–2027. Programa: 54.A. A.P., D.P. and E.E.V. have been partially funded by the Spanish Project LEARNIG PID2022-143083NB-I00 by the Agencia Estatal de Investigación.Seismic data have improved in quality and quantity over the past few decades, enabling
better statistical analysis. Statistical physics has proposed new ways to deal with these data to
focus the attention on specific matters. The present paper combines these two progressions to find
indicators that can help in the definition of areas where seismic risk is developing. Our data comes
from the IPOC catalog for 2007 to 2014. It covers the intense seismic activity near Iquique in Northern
Chile during March/April 2014. Centered in these hypocenters we concentrate on the rectangle
Lat−18
−22 and Lon−72
−68 and deepness between 5 and 70 km, where the major earthquakes originate.
The analysis was performed using two complementary techniques: Tsallis entropy and mutability
(dynamical entropy). Two possible forecasting indicators emerge: (1) Tsallis entropy (mutability)
increases (decreases) broadly about two years before the main MW 8.1 earthquake. (2) Tsallis entropy
(mutability) sharply decreases (increases) a few weeks before the MW 8.1 earthquake. The first one is
about energy accumulation, and the second one is because of energy relaxation in the parallelepiped
of interest. We discuss the implications of these behaviors and project them for possible future studies.Consejería de Universidad, Investigación e Innovación, Junta de Andalucía
PID2022-143083NB-I00, RNM104Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia
AFB220001Fondo Nacional de Desarrollo Científico y Tecnológico
1230055 FONDECYTAgencia Estatal de Investigación
PID2021-124701NBC21 y C22 AEIUniversidad de Almería
UAL2020-RNM-B1980 UA
Advantages and disadvantages of competency education in the practical subjects of the Faculty of Veterinary Medicine and Animal Science, National Autonomous University of Mexico
Resúmenes IV Congreso VetDoc de Docencia Veterinaria, León 2017 (6-7 de Julio)[ES] Desde el año 2010 en la Facultad de Medicina Veterinaria y Zootecnia de la Universidad Nacional Autónoma de México (FMVZ-UNAM), se planteó la posibilidad de adecuar el plan de estudios a un modelo educativo basado en competencias, donde el propio alumno regule el aprendizaje y adquiera además de conocimientos teóricos, herramientas para solucionar problemas y formar un criterio propio, tratando de dejar de lado los modelos educativos del siglo XX, donde el docente era el único poseedor y transmisor de conocimientos
Anisotropic magnetoresistance in colossal magnetoresistive La1−xSrxMnO3 thin films
We report on magnetic field and temperature-dependent measurements of the anisotropic magnetoresistance (AMR) in epitaxial La1−xSrxMnO3 (LSMO) thin films. While in 3d ferromagnetic alloys increasing the magnetization, either by reducing the temperature or increasing the magnetic field, increases the AMR, we find that in LSMO films the AMR dependence on magnetization displays nonmonotonic behavior which becomes particularly pronounced in lightly doped compounds. We believe that this behavior is related to the inhomogeneity exhibited by these materials
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