Fluid geochemistry and seismic activityin the period 1998-2002 at Turrialba Volcano (Costa Rica)

Turrialba Volcano, located in Central-Southern Costa Rica, has been characterized, since the last period of eruptive activity in 1884-1886, by a weak and discontinuous fumarolic activity in the western area of its summit. During the 1998-2002 period, fumaroles discharging from central and West craters were collected for chemical analyses of major and trace gas compounds, 13C/12C in CO2 and 18O/16O and D/H (in one fumarolic condensate), isotopic ratios. Geophysical measurements (seismic activity and ground deformation), monitored in the same period, were compared to geochemical data to define the status of the volcanic system. Chemical and isotopic characteristics of fumaroles of Turrialba Volcano seem to be related to interaction processes between a magmatic source and a shallower hydrothermal aquifer. Since February 1997, seismicity at Turrialba Volcano gradually increased, while since August 2001 new fumaroles start to discharge from a new fracture system located in the area between central and West craters. Since September 2001, strong compositional changes of gas discharges have been recorded at central crater. These occurrences are possibly due to variations in the permeability of the conduit system feeding the fumaroles. Heat pulse episodes from a magmatic source have possibly caused the increase of vapour pressure at depth and, consequently, favoured the uprising of the magmatic fluids toward the surface. The observed evolution of chemical and physical parameters suggests that to forecast a possible renewal of the volcanic activity in the near future a full program of both geochemical and geophysical surveillance must be provided at Turrialba Volcano

Cosmology with interaction in the dark sector

Unless some unknown symmetry in Nature prevents or suppresses a non-minimal coupling in the dark sector, the dark energy field may interact with the pressureless component of dark matter. In this paper, we investigate some cosmological consequences of a general model of interacting dark matter-dark energy characterized by a dimensionless parameter $\epsilon$. We derive a coupled scalar field version for this general class of scenarios and carry out a joint statistical analysis involving SNe Ia data ({Legacy} and {Constitution} sets), measurements of baryon acoustic oscillation peak at $z = 0.20$ (2dFGRS) and $z = 0.35$ (SDSS), and measurements of the Hubble evolution $H(z)$. For the specific case of vacuum decay ($w = -1$), we find that, although physically forbidden, a transfer of energy from dark matter to dark energy is favored by the data.Comment: 5 pages, 5 figures, LaTe

Scalar field description of a parametric model of dark energy

We investigate theoretical and observational aspects of a time-dependent parameterization for the dark energy equation of state (EoS) $w(z)$, which is a well behaved function of the redshift $z$ over the entire cosmological evolution, i.e., $z \in [-1,\infty)$. By using a theoretical algorithm of constructing the quintessence potential directly from the effective EoS parameter, we derive and discuss the general features of the resulting potential for this $w(z)$ function. Since the parameterization here discussed allows us to divide the parametric plane in defined regions associated to distinct classes of dark energy models, we use the most recent observations from type Ia supernovae, baryon acoustic oscillation peak and Cosmic Microwave Background shift parameter to check which class is observationally prefered. We show that the largest portion of the confidence contours lies into the region corresponding to a possible crossing of the so-called phanton divide line at some point of the cosmic evolution.Comment: 5 pages, 2 figures, LaTe

Distance Functions and Normalization Under Stream Scenarios

Data normalization is an essential task when modeling a classification system. When dealing with data streams, data normalization becomes especially challenging since we may not know in advance the properties of the features, such as their minimum/maximum values, and these properties may change over time. We compare the accuracies generated by eight well-known distance functions in data streams without normalization, normalized considering the statistics of the first batch of data received, and considering the previous batch received. We argue that experimental protocols for streams that consider the full stream as normalized are unrealistic and can lead to biased and poor results. Our results indicate that using the original data stream without applying normalization, and the Canberra distance, can be a good combination when no information about the data stream is known beforehand.Comment: Paper accepted to the 2023 International Joint Conference on Neural Network

The zooarchaeological record of the North stretch of Middle Paraná River, left margin (Corrientes, Argentina)

En este trabajo se integran los datos obtenidos a partir del análisis macroscópico del material faunístico recuperado en posición estratigráfica en cinco sitios emplazados en la llanura aluvial del Paraná Medio (Corrientes, Argentina). El mismo constituye una síntesis de lo realizado hasta el momento sobre esta ergología para los sitios estudiados. En esta instancia el objetivo del análisis fue generar información respecto de los procesos involucrados en la formación de los depósitos estudiados y las evidencias concretas de la acción antrópica en su composición, así como también evaluar la variabilidad del registro arqueofaunístico depositado a lo largo del bloque espacio-tiempo bajo estudio. Los resultados obtenidos permiten sostener que los agentes físicos y químicos asociados a la dinámica de un ambiente marcadamente hidrófilo limitaron en gran parte las observaciones y líneas de análisis que se pueden desarrollar. A pesar de esto, las evidencias de acción antrópica permiten sostener el origen cultural de los conjuntos estudiados. Estas dan cuenta de la explotación y procesamiento de animales acuáticos junto a ciertas especies terrestres con algún grado de dependencia del medio acuático propias de este ambiente; taxa que presentan poco riesgo de obtención dada su profusión, diversidad y presencia respecto al ciclo ecológico. La información así generada permitió considerar el área trabajada a la luz de los modelos propuestos para interpretar el registro arqueológico del Paraná Medio.This paper presents a summary of the macroscopic analysis of faunal material recovered from five archaeological sites located in Middle Paraná alluvial plain (Corrientes, Argentina). The aim of this work is to understand the formation processes, especially regarding evidence of anthropic modifications, as well as to evaluate the variability within the zooarchaeological assemblages studied. The results show that physical and chemical constraints of a seasonally wet humid subtropical environment were the main agents that caused limitations of data sets. Nevertheless, anthropic modifications support that the faunal record is product of human action. Through the information presented, it is possible to record a whole use of a wide range of taxa, with a highlighted exploitation of aquatic animals together with some land animals with a certain grade of dependence to aquatic environment; taxa that are available throughout the year. Generalizations of the archeological record from Middle Paraná River were considered in the data interpretation.

Uso actual y potencial de aguas residuales domésticas (ARD) para irrigación en la provincia de Salta, Argentina

En este trabajo se presenta un relevamiento de las principales experiencias actuales de reutilización de aguas residuales domésticas (ARD) para irrigación en la provincia de Salta, Argentina. Se identificaron tres experiencias de reúso directo y cuatro experiencias de reúso indirecto de ARD para irrigación. Las mismas se localizan en inmediaciones a los sistemas de tratamiento de líquidos cloacales. La calidad microbiológica de los efluentes indica que ningún caso cumple con las directrices propuestas por la OMS para riego irrestricto y de áreas verdes. Se estima que el potencial de reúso con ARD en la provincia asciende a unas 3500 hectáreas, considerando cultivos de referencia según la localidad. Esta estimación debe ser complementada con estudios de factibilidad para cada caso en particular. Los resultados obtenidos representan un aporte para el reconocimiento y la validación de las aguas residuales como un recurso hídrico alternativo para la región.Fil: Salas Barboza, Ariela Griselda Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Gatto D'andrea, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Garces, V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Rodriguez Alvarez, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Liberal, Viviana Isabel. Universidad Nacional de Salta; ArgentinaFil: Paoli, H.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Seghezzo, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; Argentin

Influence of remating on sterile insect technique in Ceratitis capitata (Diptera: Tephritidae): a molecular approach.

The Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae), is one of the most harmful species to world horticulture, thus requiring suppression or eradication programs. The sterile insect technique is widely used for autocidal control of nuisance insects because it neither releases exotic agents into the environment nor introduces new genetic material into existing populations. In 2005, the Moscamed Brasil biofactory imported the tsl Vienna 8 C. capitata strain from the International Atomic Energy Agency (IAEA); this action required genetic testing of the strain?s biological characteristics. The objective of this study was to discriminate males of wild populations from tsl Vienna 8 using molecular markers, and to conclude which male line dominated in a remating condition. Four crosses, each using 100 males and 100 females, were performed: wild female × wild male; wild female × tsl Vienna 8 male; wild female × wild male, followed by remating with tsl Vienna 8 males after 48 h, and wild female × tsl Vienna 8 male, followed by remating with wild males after 48 h. The results showed that the tsl Vienna 8 strain is compatible with wild females from the São Francisco Valley region and that these males can successfully transfer their sperm to the female spermathecae. Regarding remating, the sperm of the second male dominated over that of the first one. Based on these findings, the sterile insect technique success may be reduced, since the progeny of a female that remates with a wild male could be viable