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Nueve de Julio, Argentina

The National University of Chilecito is an Argentine national university situated in the city of Chilecito, La Rioja. The institution was established on December 16, 2002, on the Chilecito campus of the National University of La Rioja. It maintains schools of Law, Engineering, Licentiate, Technology, and Education. Wikipedia.

Dantur Juri M.J.,National University of Tucuman | Dantur Juri M.J.,National University of Chilecito | Veggiani Aybar C.A.,National University of Tucuman | Ortega E.S.,National University of Tucuman | And 2 more authors.
Malaria Journal | Year: 2013

A case of co-infection with Plasmodium vivax and Mansonella ozzardi was detected in a blood sample from a person who had shown symptoms of malaria and lived in a city that was close to the Argentina/Bolivia border. The case was detected during a random revision of thick and thin smears from patients diagnosed with malaria from various towns and cities located in north-western Argentina between 1983 and 2001. Trophozoites of P. vivax were observed in the thin blood smear along with M. ozzardi microfilaria (larval form), which presented a long, slender, pointed anucleate tail and the absence of the sheath. This last characteristic is shared with Mansonella perstans, Mansonella streptocerca and Onchocerca volvulus. More rigorously controlled studies to detect other co-infection cases in the area as well as the possibility of importation from Bolivia into Argentina are currently ongoing. The relationship between the malaria parasite and microfilaria, the potential effect of malaria treatment on the development of M. ozzardi, and the possible impact of this microfilaria on the immunity of a person against P. vivax are all still unknown. This contribution constitutes a point of focus for future studies involving the interaction between the parasites and the potential risk that humans are exposed to. © 2013 Dantur Juri et al.; licensee BioMed Central Ltd. Source

Saggese M.D.,Western University of Health Sciences | Roesler I.,University of Buenos Aires | Marano C.F.,National University of Chilecito
Journal of Raptor Research | Year: 2014

The migratory subspecies of the "American" Osprey (Pandion haliaetus carolinensis) breeds across most of North America. Most of these Ospreys winter north of the equator, although significant numbers travel farther south, reaching Argentina. The number of Osprey sightings in Argentina has increased since the first review of their status in this country. We analyzed records of Osprey migration and distribution in Argentina from 1993 to 2008. We found that Ospreys occur year-round in Argentina, with a higher concentration in spring to summer (1 October to 31 March). Our data confirmed that in northern and northeastern Argentina, Ospreys use river systems and their major tributaries, and in central and northwestern regions, they commonly frequent reservoirs. The apparent increase in the number of Osprey records in Argentina in the last decades may result from an actual population increase but may also reflect a larger number of observers. Recent records suggest that Osprey should be considered a regular visitor to northern Argentina. We confirm the importance of northeastern rivers, and central and northwestern reservoirs as wintering areas. Argentina has been noted as an important wintering area for many migratory birds, but has been underestimated as a wintering area for Osprey. © 2014 The Raptor Research Foundation, Inc. Source

Cherbiy-Hoffmann S.U.,CONICET | Cherbiy-Hoffmann S.U.,National University of Chilecito | Hall A.J.,University of Buenos Aires | Searles P.S.,CONICET | Rousseaux M.C.,CONICET
Scientia Horticulturae | Year: 2015

Shading for short periods during potentially critical phenological phases can improve our understanding of the processes underlying the reductions in crop performance when solar radiation is limiting in high density orchards. Our objective was to evaluate the effects of three separate 30 day-long shade periods imposed during fruit set (FS), endocarp sclerification (ES), and early oil accumulation (OA) on some oil yield determinants and components in olive. Four shading levels (3, 20, 40, and 70% of incident photosynthetically active radiation; PAR) were applied in each period using shade cloths that surrounded one-half of large individual trees. Individual fruit dry weight, oil concentration (%) on a dry weight basis, and non-fruiting branch growth were determined at the end of each shading period, 45 days after their completion, and at the end of the season. The previously shaded- and the unshaded-halves of each tree were also harvested at the end of the season to obtain fruit number and oil yield for each half-tree. Individual fruit dry weight and oil concentration at the end of all three shading periods were decreased by shading due to reduced absolute rates of fruit growth and oil accumulation, respectively. However, at final harvest, there were no statistically significant treatment differences in individual fruit weight. By contrast, a small reduction in oil concentration persisted in the fruit from trees subjected to heavy shading during the OA period. Oil yield per half-tree at end of the season was decreased by shading applied during FS and OA periods, principally due to decreases in fruit number and oil concentration, respectively. Final oil yield was not affected by shading during the ES period. Elongation of non-fruiting branches was only decreased by shading during the early spring FS period, when vegetative growth was somewhat more sensitive to shading than fruit growth. Lastly, no consistent response of return bloom to the shading periods was detected the following spring. Our results suggest that the FS period when fruit number is defined and the OA period are more critical for determining final oil yield than the ES period. This information could provide guidance for the design of more effective management strategies in high density orchards where shading can play a key role. © 2015 Elsevier B.V. Source

Ortiz P.E.,National University of Tucuman | Ortiz P.E.,CONICET | Madozzo Jaen M.C.,National University of Tucuman | Jayat J.P.,National University of Tucuman | Jayat J.P.,National University of Chilecito
Journal of Arid Environments | Year: 2012

The understanding of the Holocene climatic fluctuations through the study of micromammal sequences can help to know the current environmental dynamic in arid lands. This is relevant because of the accelerated transformation that these environments are undergoing. We report the first stratified micromammal assemblage from the Monte desert on Northwestern Argentina, which span the last two millennia. We studied 11 700 cranial remains accumulated by owls's trophic activities, representing 16 species (MNI  5031). The assemblage composition is consistent with the species found in the area today, being the dominant Phyllotis xanthopygus, Eligmodontia spp., and Calomys musculinus. Relative frequencies and diversity show slight variations throughout the sequence, suggesting environmental stability. However, minor changes for several species indicate small-scale variations. We infer climatic conditions similar to those of the present for the period of 1600-1300 yBP, wetter conditions for 1000-600 yBP, and a return to xeric conditions up until the present. This reconstruction agrees with previous interpretations regarding global climatic dynamics, as those involving the Medieval Warm Period and the Little Ice Age. Since there are no areas potentially affected by agricultural activities within the owl's hunting area, the fluctuations are interpreted as primarily the result of changes in climatic conditions. © 2011 Elsevier Ltd. Source

Pelegrin N.,CONICET | Chani J.M.,National University of Chilecito | Echevarria A.L.,Institute Vertebrados Fundacion Miguel Lillo | Bucher E.H.,CONICET
Acta Oecologica | Year: 2013

Lizards partition resources in three main niche dimensions: time, space and food. Activity time and microhabitat use are strongly influenced by thermal environment, and may differ between species according to thermal requirements and tolerance. As thermal characteristics are influenced by habitat structure, microhabitat use and activity of lizards can change in disturbed habitats. We compared activity and microhabitat use of two abundant lizard species of the Semi-arid Chaco of Argentina between a restored and a highly degraded Chaco forest, to determine how habitat degradation affects lizard segregation in time and space, hypothesizing that as activity and microhabitat use of lizards are related to habitat structure, activity and microhabitat use of individual species can be altered in degraded habitats, thus changing segregation patterns between them. Activity changed from an overlapped pattern in a restored forest to a segregated pattern in a degraded forest. A similar trend was observed for microhabitat use, although to a less extent. No correlation was found between air temperature and lizard activity, but lizard activity varied along the day and among sites. Contrary to what was believed, activity patterns of neotropical diurnal lizards are not fixed, but affected by multiple factors related to habitat structure and possibly to interspecific interactions. Changes in activity patterns and microhabitat use in degraded forests may have important implications when analyzing the effects of climate change on lizard species, due to synergistic effects.© 2013 Elsevier Masson SAS. Source

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