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San Fernando del Valle de Catamarca, Argentina

Montes C.,NASA | Rutllant J.A.,Catolica del Norte University | Rutllant J.A.,University of Chile | Aguirre A.,University of Aconcagua | And 2 more authors.
Journal of Applied Meteorology and Climatology | Year: 2016

The terral de Vicuña is a warm and dry wind that flows down the Elqui Valley in north-central Chile typically at dawn and early morning. Given that most terral episodes occur in austral winter when chill accumulation by deciduous fruit trees proceeds, negative effects on agriculture may be expected. During 11 (2004-14) winters a meteorological characterization of terral winds and the assessment of their impact on chill accumulation, by the modified Utah Model and the Dynamic Model, were performed. Within this period, 67 terral days (TD) were identified as those in which nighttime to early morning wind direction and speed, air temperature, and relative humidity reached defined thresholds on an hourly basis (terral hours). Most frequent TD featured 6-9 consecutive terral hours; duration is considered here as a proxy for their intensity. Synoptic-scale meteorological analysis shows that 65% of moderate and strong terral events develop as a cold, migratory anticyclone drifts poleward of the study area, coinciding with the onset of a midtropospheric ridge over central Chile, bringing southwest winds on top of the Andes (~500-hPa level). The remaining 35% are either associated with 500-hPa easterlies (foehn like), with prefrontal conditions ahead of a trough driving northwest 500-hPa winds, or with transitional 500-hPa westerlies. Assessments of chill accumulation during TD show that, although present average and cold winter conditions do not represent a major TD hazard to local agriculture, lower chill accumulation associated with anomalously high nocturnal temperatures could be significantly more important during present and future warmer winters. © 2016 American Meteorological Society.

Based on available definitions of tourist resources and tourist attractions, several coincidences, excesses and omissions are identified: The functional variable and the conversion state define the difference between resources and attractions. Then, two classifications are proposed for both categories: resources (considering system approaches and UNESCO typology) and attractions (attending the assessment of its resources andrepresentations as well as the capacity or necessity of being managed). Moreover, assessment tools are propounded for both study objects in view of remarkable characteristics (for resources) and actions taken (for attractions).

Sassi P.L.,CONICET | Taraborelli P.,CONICET | Albanese S.,CONICET | Gutierrez A.,University of Aconcagua
Ethology | Year: 2015

The activity rhythm of a species is ruled by internal signals as well as external factors. Among them, ambient temperature strongly influences the amount, duration, and distribution of an organism's activities throughout the day. The result is a pattern of activity that, between certain limits, can be flexible to deal with seasonal and spatial thermal heterogeneity. The range of behavioral plasticity increases with environmental variability and could be beneficial for a species' persistence under novel conditions. Thus, the goal of this study was to experimentally explore the behavioral plasticity in Phyllotis xanthopygus, a rodent species inhabiting an altitudinal gradient in the Central Andes Mountains of Argentina. In the laboratory, we assessed activity rate and pattern under different temperatures by comparing groups of individuals collected at different altitudes. All animals were acclimated to subsequent thermal treatments in a paired design. As expected, P. xanthophygus showed changes in activity under different temperatures, and animals from diverse altitudes were differently affected. In particular, animals from mid-altitudes and high altitudes reduced their activity under high temperatures. Intraspecific differences across the altitudinal gradient suggest that animals from mid-altitudes and high altitudes are less heat tolerant than those from lower sites, in spite of acclimation to equal conditions. We propose that climate ranges experienced in the field possibly promote this different response. Our results are discussed in light of recent forecasts of temperature rises in the region, which could constrain P. xanthophygus activity in space and time. © 2015 Blackwell Verlag GmbH.

In the present paper, the concept of incommensurability is analyzed in the light of what is happening in different disciplines related to psychology. it is detected that there are many concepts that are applied in different studies without a conceptual elaboration or re-elaboration from new attributes identified in a certain phenomenon. Sometimes it consists of merely adding together many terms; in other cases, concepts are transferred without specifying the ontology or taxonomy of which they are part. two theoretical works are described - one by castorina and the other one by Bruner - to exemplify the arguments expressed. Finally, it is argued that a certain margin of common space would exist between psychological theories, which could be represented, for example, in the resolution of "problems" (both theoretical and empirical). that is to say, a theory is valid while it is questionned by an important sector of the scientific community (mainly for research and secondarily for professional practice).

Bordonaro O.L.,Centro Cientifico Tecnologico | Pratt B.R.,University of Saskatchewan | Robledo V.,University of Aconcagua
Geological Journal | Year: 2013

The ptychoparioid trilobite Blainia gregaria Walcott, 1916 is described for the first time from the late middle Cambrian (Series 3) of the Argentine Precordillera. It occurs commonly in the upper part of La Laja Formation, a carbonate platform succession that crops out in the Precordillera Oriental of San Juan where it reaches a thickness of some 600m. Sections were sampled on cerro Tres Marías in Sierra de Marquesado and in quebrada de Zonda at the northern termination of Sierra Chica de Zonda. More than 1200 specimens were recovered from 22 stratigraphic levels over a thickness of 155m, located in the uppermost 15m of the Soldano Member, the approximately 100m thick Rivadavia Member, and in the lower 40m of the Juan Pobre Member. Our biometric study dealt with 205 cranidia and 365 pygidia from cerro Tres Marías. Measured dimensions of a subset of this collection provide bivariate datasets that in some characters show broad scatter plots and relatively low linear correlation coefficients, indicative of rather wide intraspecific morphological variation. Six morphotypes (three cranidial and three pygidial), recognized mainly on the basis of shape, occur together in the same collections. This evidence for an unusually high degree of variability leads to a proposed synonymy of some 30 previously named species in North America belonging to two genera, Blainia Walcott, 1916 and Glyphaspis Poulsen, 1927, the latter considered a junior synonym. The biogeographic distribution of B. gregaria, as redefined here, shows that it was an endemic Laurentian species that inhabited the inner parts of the carbonate platform that rimmed the craton and mantled portions of its interior. Its presence in western Argentina is further evidence for the very close faunal relationship between the Precordilleran terrane, known as Cuyania, and Laurentia during the Cambrian. © 2012 John Wiley & Sons, Ltd.

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