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In this study, we conducted a survey of newly discovered populations of tuco-tuco (subterranean rodents of the genus Ctenomys) in the Entre Ríos province, in an area characterized by its unexplored nature and its climatic and biogeographic complexity within Argentina, which includes two National Parks. We characterize the nucleotide sequences of the cytochrome-b gene, revealing the presence of seven novel haplotypes within Ctenomys rionegrensis, a species known to inhabit both sides of the Uruguay River. Through Bayesian analyses, we estimated the divergence times of the oldest lineages of C. rionegrensis, as well as those of the haplotypes located east of the Uruguay River, dating back approximately 630,000 years before present (ybp) and 526,000 ybp, respectively. These estimates correspond with significant paleogeographic events in the region. Our findings may raise questions regarding the taxonomic classification of the species and suggest potential modifications to its current endangered status as designated by the International Union for Conservation of Nature (IUCN). Consequently, this research provides valuable insights that may inform future revisions of the species' conservation status and guide the development of informed management strategies/policies. [ABSTRACT FROM AUTHOR]

The Pampas deer (Ozotoceros bezoarticus) is an endangered ungulate from South American. The following paper presents the first investigation on the isotopic ecology (δ13Ccollagen; δ15Ncollagen) of modern populations of Pampas deer. The information obtained is compared with new δ13C and δ15N data of Pampas deer bones recovered from archaeological sites in the Central Pampean Dunefields (Inland Pampa phytogeographic area) and with previously published archeofaunistic isotope data for sites from eastern central Argentina. The range of δ13C values of Pampas deer is broad, ranging from a diet dominated by C3 plants to a mixed diet of C3 and C4 plants. The δ15N values mainly show distinct signals between the Atlantic coast and the interior. The diet breadth of the Pampas deer suggests a high adaptability to different environments, a crucial factor for conservation programs of this species. The δ13C values of the Inland Pampa do not show great differences between the Middle Holocene, Late Holocene and today. Adaptation strategies of the Pampas deer to the environmental changes during the Holocene were not associated with a modification of their feeding habits, but rather with social and demographic strategies. These variations in ecology conditioned the predictability of this prey for hunter-gatherers. [ABSTRACT FROM AUTHOR]

Recent political changes suggest that Argentina has started a process in which demands for greater transparency in public affairs require a redesign of decision-making processes. Nevertheless, the most challenging feature in the Argentine political-institutional environment is the lack of incentives for introducing better regulation policies. This situation is a consequence – inter alia – of political instability and recurrent economic crises. This article analyses the current situation in Argentina regarding the concept of rational law-making, from the perspective of evidence-based legislative process and procedural judicial review. We conclude that even acknowledging the weight of the longstanding tradition of judicial deference to the legislature and the absence of procedural standards that guide the legislative process, certain judicial decisions hint at the beginning of a path in which traditional constitutional review – basically substantive – incorporates judicial review of rational law-making in order to improve the quality of democracy. The scope of legislative procedural review is open to debate. [ABSTRACT FROM PUBLISHER]

Pampas deer ( Ozotoceros bezoarticus) is a medium-sized South American cervid associated with savannas and grasslands in Argentina, Brazil, Bolivia, Uruguay, and Paraguay. Currently, four isolated population nuclei occur in Argentina, with the largest one located in the semiarid grasslands of San Luis Province. The aim of this work was to describe the social organization of this local population and to determine and analyze the factors that influence it. The most frequent groups found were mixed groups (34.82%), followed by solitary males (18.64%), and solitary females (15.00%). Differences in group type occurrence were found in three periods: dry, early rainy, and late rainy seasons. Mixed groups were more frequent during the dry season. The sexual segregation-aggregation statistic showed statistically significant segregation only in January and November. In addition, we analyzed the social grouping patterns during an annual cycle; the mean group size was 2.49±0.46 and Jarman's typical group size was 3.84±1.08 (individuals/group). A mixed-model nested ANOVA showed marked differences in terms of group sizes between habitat types and seasons. The social organization of the Pampas deer in San Luis is similar to that of the other populations of this species, despite occupying a different environment type and exhibiting disparate feeding styles and density values. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of soybean crop fields by pampas deer, Ozotoceros bezoarticus, in San Luis Province, Argentina. It mentions that the largest portion of Ozotoceros bezoarticus population lives in the semi-arid grasslands of south-central San Louis. It states that the region has undergone changes in land use brought by cattle ranching. It notes that the study assessed the use of soybean crop fields by Ozotoceros bezoarticus through performing monthly drive counts from June 2006 to August 2007. It adds that the nutritional quality of soybean and grasslands were also approximated.

In Argentina, domestic pigs (Sus scrofa Linnaeus 1758) were introduced during the first Buenos Aires foundation, in the year 1536. Their provenance was mainly from the Iberian Peninsula, the Canary Islands and Cape Verde. In 1541 those pigs were released and, consequently, the first feral populations were originated. Thereafter, the species propagated both naturally and through human action, reaching a distribution that covers most of the Argentinian territory. The objective of this study is to genetically characterize the oldest feral pig populations in Argentina, making use of the mitochondrial control region (CR) and the amelogenin gene (AmelY), in order to determine their phylogenetic origin and corroborate its consistency with the historic information. The obtained results indicate that most of the feral pigs in Corrientes and Buenos Aires populations are positioned in the European subclades, E1-A and E1-C for CR, and HY1 and HY2 for AmelY. Despite this fact, a low frequency of individuals of Asian origin was found in populations from Buenos Aires, whereas none of them disclosed African ancestry. Furthermore, given that a large proportion of feral pigs found in the species' original sites in Argentina have European ancestry, we can partially corroborate the historical records. [ABSTRACT FROM AUTHOR]

The availability of population-based epidemiological data on the incident risk of stroke is very scarce in Argentina and other Latin American countries. In response to the priorities established by the World Health Organization and the United Nations, PREVISTA was envisaged as a population-based program to determine the risk of first-ever and recurrent stroke and transient ischemic attack incidence and mortality in Tandil, Buenos Aires, Argentina. The study will be conducted according to Standardized Tools for Stroke Surveillance (STEPS Stroke) methodology and will enroll all new (incident) and recurrent consecutive cases of stroke and transient ischemic attack in the City of Tandil between May 1st, 2013 and April 30, 2015. The study will include patients with ischemic stroke, non-traumatic primary intracerebral hemorrhage, subarachnoid hemorrhage, and transient ischemic attack. To ensure the inclusion of every cerebrovascular event during an observation period of two years, we will instrument an 'intensive screening program', consisting of a comprehensive daily tracking of every potential event of stroke or transient ischemic attack using multiple overlapping sources. Mortality would be determined during follow-up for every enrolled patient. Also, fatal community events would be screened daily through revision of death certificates at funeral homes and local offices of vital statistics. All causes of death will be adjudicated by an ad-hoc committee. The close population of Tandil is representative of a large proportion of Latin-American countries with low- and middle-income economies. The findings and conclusions of PREVISTA may provide data that could support future health policy decision-making in the region., (© 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.)

Background: Laparoscopic liver resections are 1 of the most complex procedures in hepatobiliary surgery. During the last 20 years, laparoscopic liver surgery has had an important development in specialized centers., Objective: To describe the initial experience in laparoscopic liver resection for benign and malignant tumors, to assess its indications and outcomes, and to describe technical aspects of these resections., Methods: Review of the records of 28 patients who underwent laparoscopic liver resection between November 2000 and November 2007. Analysis of the data regarding preoperative management and postoperative outcomes., Results: Twenty-six liver resections were performed laparoscopically (20 purely laparoscopic, 3 hand assisted, and 3 hybrid technique) and 2 were converted to open surgery. The laparoscopic approach was attempted in 6% (28 out of 459) of the liver resections carried out in the analyzed period. Indications for resection were: benign tumors in 22 patients (78%) and malignant tumors in 6 patients (22%). Resections were minor in 27 patients (96%) and major in 1 patient (4%). Pringle maneuver was performed in 14 patients (50%). Margins were negative in all the cases. Mean operative time was 170 minutes (range 70 to 350), and the mean length of stay was 3 days (range 1 to 6). Mortality rate was 0%. Only 2 patients (7%) had postoperative minor complications (self-limited bile leaks)., Conclusions: In selected patients with benign and malignant liver tumors, laparoscopic liver resections can be safely performed. This procedure must be carried out by the surgeons trained in both the hepatobiliary and laparoscopic surgery.