Search results for "south america"
showing 10 items of 98 documents
Population response during an Oceanic Anoxic Event: The case of Posidonotis (Bivalvia) from the Lower Jurassic of the Neuquén Basin, Argentina
2019
Benthonic marine species show a wide range of biological reactions to seawater chemical changes through time, from subtle adjustments to extinction. The Early Toarcian Oceanic Anoxic Event (T-OAE) was recently recognized in the Neuquén Basin, Argentina, confirming its global scope. The event was identified chemostratigraphically on the basis of a relative increase in marine organic carbon and a characteristic negative carbon-isotope excursion (δ13Corg) in bulk rock and fossil wood in the upper Pliensbachian–lower Toarcian interval in the Arroyo Lapa section (Neuquén). Simultaneously with collection of lithological samples, a high-resolution biostratigraphical survey was carried out, and the…
Getting support in polarized societies: Income, social networks, and socioeconomic context
2013
AbstractThis paper explores how unequal resources and social and economic polarization affects the size of social networks and their use to access resources. We argue that individual resource position generates divergent expectations with regard to the impact of polarization on the size of networks on one hand, and their usefulness for accessing resources on the other. Social and economic polarization encourages reliance on informal networks, but those at the bottom of the social structure are forced to rely on more extensive networks than the wealthy to compensate for their isolated and underprivileged position. At the same time, social and economic polarization limits the resources the po…
Redes de colaboración y producción científica sudamericana en medicina clínica, ISI Current Contents 2000-2009
2012
Background International collaboration is increasingly used in biomedical research. Aim To describe the characteristics of scientific production in Latin America and the main international collaboration networks for the period 2000 to 2009. Material and methods Search for papers generated in Latin American countries in the Clinical Medicine database of ISI Web of Knowledge v.4.10 - Current Contents Connect. The country of origin of the corresponding author was considered the producing country of the paper. International collaboration was analyzed calculating the number of countries that contributed to the generation of a particular paper. Collaboration networks were graphed to determine the…
Dataset for the manuscript "Are remote sensing evapotranspiration models reliable 2 across South American ecoregions?" published in WRR
2021
Metadata of ‘Are remote sensing evapotranspiration models reliable across South American ecoregions?’ This document describes the file formatting and data used to run and evaluate the evapotranspiration models in this study. Because forcing data varies among models, each input file contains a different set of meteorological data placed within a folder named after the corresponding model. File format and time stamps Data files are CSV formatted with timestamps in the first column of the file. The following timestamps are used: GLEAM: Year (YYYY); Day of Year (DDD) PT-JPL: Year (YYYY); Month (MM); Day (DD) PM-MOD: Year (YYYY); Month (MM); Day (DD) PM-VI: Date (MM/DD/YYYY) Missing data Missing…
Reconstruction of the evolutionary history of Saccharomyces cerevisiae x S. kudriavzevii hybrids based on multilocus sequence analysis.
2012
In recent years, interspecific hybridization and introgression are increasingly recognized as significant events in the evolution of Saccharomyces yeasts. These mechanisms have probably been involved in the origin of novel yeast genotypes and phenotypes, which in due course were to colonize and predominate in the new fermentative environments created by human manipulation. The particular conditions in which hybrids arose are still unknown, as well as the number of possible hybridization events that generated the whole set of natural hybrids described in the literature during recent years. In this study, we could infer at least six different hybridization events that originated a set of 26 S…
Personal protective equipment and intensive care unit healthcare worker safety in the COVID-19 era (PPE-SAFE): An international survey
2020
Purpose To survey healthcare workers (HCW) on availability and use of personal protective equipment (PPE) caring for COVID-19 patients in the intensive care unit (ICU). Materials and method A web-based survey distributed worldwide in April 2020. Results We received 2711 responses from 1797 (67%) physicians, 744 (27%) nurses, and 170 (6%) Allied HCW. For routine care, most (1557, 58%) reportedly used FFP2/N95 masks, waterproof long sleeve gowns (1623; 67%), and face shields/visors (1574; 62%). Powered Air-Purifying Respirators were used routinely and for intubation only by 184 (7%) and 254 (13%) respondents, respectively. Surgical masks were used for routine care by 289 (15%) and 47 (2%) for…
Remote sensing and climate data as a key for understanding fasciolosis transmission in the Andes: review and update of an ongoing interdisciplinary p…
2006
Fasciolosis caused by Fasciola hepatica in various South American countries located on the slopes of the Andes has been recognized as an important public health problem. However, the importance of this zoonotic hepatic parasite was neglected until the last decade. Countries such as Peru and Bolivia are considered to be hyperendemic areas for human and animal fasciolosis, and other countries such as Chile, Ecuador, Colombia and Venezuela are also affected. At the beginning of the 1990s a multidisciplinary project was launched with the aim to shed light on the problems related to this parasitic disease in the Northern Bolivian Altiplano. A few years later, a geographic information system (GIS…
Anti-inflammatory Effects of South American Tanacetum vulgare
1998
Abstract In recent years the role of phenolic compounds and sesquiterpene lactones, particularly parthenolide, in the anti-migraine and anti-inflammatory effects of Tanacetum parthenium (Asteraceae) has attracted much attention. However, the closely-related cosmopolitan species T. vulgare has remained outside the mainstream of research in this field. After treating the aerial parts of T. vulgare with dichloromethane and methanol, and applying conventional column and thin-layer chromatographic techniques, it was possible to isolate from the moderately lipophilic fractions the principles responsible for the anti-inflammatory activity of this plant against the mouse-ear oedema induced by 12-O-…
Genetic variability ofTriatoma rubrovaria(Reduviidae: Triatominae) from Brazil, Argentina and Uruguay as revealed by two different molecular markers
2007
Randomly amplified polymorphic DNA (RAPD) and nuclear ribosomal DNA sequence analyses were used to assess the genetic population structure of the South American triatomine species Triatomo rubrovario throughout its geographical distribution. To investigate the genetic variability at both intraspecific and intrapopulational levels the RAPD profiles and the nucleotide sequences of the rDNA intergenic spacers, ITS-1 and ITS-2, were analysed and compared. The phenetic analysis based on RAPD profiles show three distinct clusters diverging by similarity coefficients ranging from 0.62 to 0.96. The ITS-1 and ITS-2 sequence variability detected may be considered very high, suggesting reproductive is…