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Copyright of Revista de la Sociedad Entomológica Argentina is the property of Sociedad Entomologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: Anatomy is considered critical to understanding the size and shape of the different systems of animals belonging to the same group or individuals that are close in the phylogenetic scale. In the case of the Franciscana dolphin or Pontoporia blainvillei, the digestive apparatus shows some differential characteristics compared to other dolphins or other marine mammals. In the present work, the authors try to demonstrate whether these characteristics are conditioned by the animal's own diet or if they have more to do with certain phylogenetic adaptations. Considering that the Franciscana dolphin is an endangered species, any work that could facilitate better knowledge of these individuals has a high social, ecological, and scientific value because it will help in their care and conservation, and this is of utmost importance to implement effective management strategies for this species. The Franciscana (also known as the La Plata River Dolphin) is a small dolphin that lives in the coastal waters of Brazil, Uruguay, and Argentina. This species is considered the most endangered marine mammal in the western South Atlantic Ocean. Anatomic dissection of the digestive system of 19 animals of different ages, including 2 neonates, 12 juveniles, and 5 adults, was performed. Parameters related to length, breadth, weight, and diameter of the digestive viscera were considered in each case. Our results show that the Franciscana dolphin presents differential characteristics in relation to several parts of the digestive system, including, specifically, the tongue, the teeth, the stomach, and the small intestine. Thus, this paper add precious information to the actual knowledge of this vulnerable marine mammal species in order to improve conservation efforts. [ABSTRACT FROM AUTHOR]

Identifying at-risk infants for retinopathy of prematurity (ROP) is complex in countries with emerging economies as infants that lack conventional risk factors, such as low birth weight (BW) and young gestational age (GA), still go on to develop severe ROP. Potential biomarkers, like serum insulin-like growth factor 1 (IGF-1) and slow postnatal weight gain, have been identified as good predictors for ROP in developed countries. We sought to determine the relationship between IGF-1 levels and ROP in two Latin American countries where the burden of disease is still significant. Prospective cohort study of infants in Guadalajara, Mexico and La Plata, Argentina. Filter-paper bloodspot IGF-1 assays were performed weekly from birth until hospital discharge or 40 weeks' postmenstrual age (PMA). 112 infants were studied with a median BW of 1412 g (range 620 g-2390 g) and a median GA of 33 weeks (range 25–37). There was no significant difference in IGF-1 between infants who developed ROP and those who did not. Low IGF-1 was not associated with ROP in these infants. The lack of an association between ROP and IGF-1 in Latin America supports the observation that growth-based predictive models do not perform as well in this setting where more mature babies still develop severe ROP. [ABSTRACT FROM AUTHOR]

This paper presents a new haploporid digenean that expands the number of species of Saccoccoelioides to 27. The new species, Saccocoelioides kirchneri n. sp. was collected from the intestine of Cnesterodon decemmaculatus (Poeciliidae: Cyprinodontiformes) from Lago del Bosque, La Plata, Argentina. The new species possesses the diagnostic features for Saccocoelioides: a sac like ceca; the vitellarium confined in two irregular groups of follicles distributed between the ventral sucker and the anterior margin of the testis; and a uterus confined largely in the hind-body, but encroaching into the range of the ventral sucker. The new species is differentiated from the 26 congeners by the body size, pharynx size, ventral sucker size, posterior extent of ceca, posterior extent of uterus and egg size. S. kirchneri n. sp. also is supported by the molecular analysis. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Action Research is the property of Verlag Barbara Budrich GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper aims to estimate the variation of the combined dependable energy output of the set of major hydropower plants within the Brazilian part of the La Plata Basin due to possible climate changes during the twenty-first century. It uses and compares the predictions of two regional climate models, namely PROMES [Castro, M., Fernández, C., and Gaertner, M.A., 1993. Description of a mesoscale atmospheric numerical model. In: J.I. Díaz and J.L. Lions, eds.Mathematics, climate and environment. Rech. Math. Appl. Ser. Mason, 230–253; Gallardo, A., Galvan, C., and Mermejo, R., 2012.PROMES-MOSLEF: An atmosphere-ocean coupled regional model. Coupling and preliminary results over the Mediterranean basin. 4th HYMEX Workshop 2 2010] and RCA models [Rummukainem, M., 2010. State-of-the-art with regional climate models.WIREs Climate Change, 1, 82–96]. Rainfall and temperature predictions are converted into streamflow at key gauge stations using Variable Infiltration Capacity Model [Liang, X., Lettenmaier, D.P., Wood, E.F., and Burges, E.F., 1994. A simple hydrologically based model of land surface water and energy fluxes for general circulation models.Journal of Geophysical Research, 99, n. D7, 14,451–14,428]. The evaluation of the dependable energy output used the natural energy hydrograph method engineering consultants (Canambra Engineering Consultants, 1969.Power study of South Brazil. 13 v. Appendice XVII Final Report. Rio de Janeiro: Canambra Engineering Consultants), combined with the Monte Carlo simulation of synthetic series of natural energy. The main contribution of this paper is the consolidation of a methodology that provides estimates of the system's dependable energy as a function of the return period for both observed and future predicted streamflows. As a conclusion, a reduction of the dependable energy output of the hydropower plants within the La Plata Basin could be expected during the twenty-first century [ABSTRACT FROM PUBLISHER]

This paper reviews recent progress made in our understanding of the functioning and variability of the South American Monsoon System (SAMS) on time scales varying from synoptic to long-term variability and climate change. The SAMS contains one of the most prominent summertime climate patterns in South America, featuring a strong seasonal variability in a region lying between the Amazon and the La Plata Basin. Much of the recent progress is derived from complementary international programs, such as the Monsoon Experiment South America (MESA), as well as from ongoing international programs such as the Large Scale Biosphere Atmosphere Experiment in the Amazon Basin (LBA) and the La Plata Basin (LPB) Regional Hydroclimate Project, which includes the CLARIS LPB Europe-South America Network for Climate Change Assessment and Impact Studies in La Plata Basin Project. The latter assesses atmosphere-land surface interactions, the role of land use changes and aerosols from biomass burning considered as sources of variability and change in the SAMS functioning, characteristics and behaviour. The SAMS region is particularly susceptible to variations of climate due to the importance of hydroelectricity generation and the agricultural base of local economies. Also addressed in this report are projections of climate change and extremes, which are important for impact and vulnerability assessments. This discussion includes the need to identify and understand important processes that control the monsoonal climate, how these processes may vary and change, and how they may interact with key societal sectors, including water resource management, hydroelectric generation, agriculture, and agribusiness. This paper reports on the major contributions of MESA to the knowledge of characteristics, functioning and variability of the SAMS, and is based on recent studies and publications, and can be considered as an update of a previous review by C. S. Vera et al. (2006a). Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

This article examines the dialogues and intersections between science and literature regarding Ernesto Sabato. A close reading of his scientific, science-related and literary texts and the account of the most significant facts of his career during the 1930's, 1940's and early 1950's, as well as an archival review of his files in La Plata, Buenos Aires and Paris in the same period of time, reveal how his scientific and literary works are intertwined manifestations of the same talent and sensitivity, and that, in the end, all of Sabato's writing should be considered scientific. [ABSTRACT FROM AUTHOR]

In a Climate Change context, it is relevant to assess the potential impacts of variations of climate drivers on sediment yield from basins with high soil exportation rates. This paper develops a methodology, based on the erosion potential method, which was applied to the upper basins of Bermejo and Pilcomayo Rivers (in the Upper Plata Basin), to estimate future trends in sediment yield. Projections for climate drivers (rainfall and temperature) were obtained through four regional climate models, with boundary conditions provided by three global climate models, for the period 2011–2100. Satellite imagery and gridded climate data were used to implement the sediment yield baseline scenario (1961–1990), which was calibrated based on solid discharge data. The model was used to determine projections of sediment yields, as time series of mean annual values for each basin. The analysis was performed on average for three-decadal periods, namely, the scenarios of ‘near future’ (2011–2040), for which current yields are essentially maintained; ‘intermediate future’ (2041–2070), where a reduction trend is detected; and ‘far future’ (2071–2100), with a recovery of yields, which even increase above the baseline scenario rate in the case of the Bermejo Upper Basin. [ABSTRACT FROM PUBLISHER]

This paper presents an analysis of the sediment dynamics that takes place at different scales within the Middle and the Lower Parana River in the La Plata Basin. The aim of this study is to provide a multi-disciplinary and multi-scale approach for the prediction of river future morphology in the context of climate change, the intended use of which is the prognosis of river morphodynamics’ long-term impact on manmade structures and activities over or near the river. The study is based on three levels of mathematical modelling, with the output of wider-scale models providing the input conditions for more specific ones. Climate models give the input ensemble, i.e. future precipitation and temperature over La Plata Basin. The semi-distributed macroscale variable infiltration capacity hydrological model simulates the flow discharge time series that are applied to an own-developed 1D morphodynamic model. The 1D model simulates future rate of sediment transport and corresponding bed-level changes at watershed scale and provides the boundary conditions for a 2D model. Therefore, streamflow divagations at channel scale are simulated by means of the MIKE21C code developed by the Danish Hydraulic Institute. The analysis indicates a rather low sensitivity of the Parana River bed profile, i.e. 1D morphology, to the increase predicted in flow discharge, whereas the streamflow appreciably divagates. In particular, surpassing an upper bound in the most frequent discharge appears effective in driving the actual bifurcated morphology into a meandering-multithread configuration. [ABSTRACT FROM PUBLISHER]

In this paper, the effects of land cover changes on the climate of the La Plata Basin in southern South America are investigated using the Weather and Research Forecasting (WRF) Model configured on a 30/10-km two-way interactive nested grid. To assess the regional climate changes resulting from land surface changes, the standard land cover types are replaced by time-varying Ecosystem Functional Types (EFTs), which is a newly devised land-cover classification that characterizes the spatial and interannual variability of surface vegetation dynamics. These variations indicate that natural and anthropogenic activities have caused changes in the surface physical parameters of the basin, such as albedo and roughness length, that contributed to regional climate changes. EFTs are obtained from functional attributes of vegetation computed from properties of the Normalized Difference Vegetation Index (NDVI) to represent patches of the land surface with homogeneous energy and gas exchanges with the atmosphere. Four simulations are conducted, each experimental period ranging from September to November in two contrasting years, 1988 and 1998. The influence of an identical EFT change on the surface heat fluxes, 2-m temperature and humidity, 10-m winds, convective instabilities and large-scale moisture fluxes and precipitation are explored for 1988 (a dry year) and 1998 (a wet year). Results show that the surface and atmospheric climate has a larger response to the same EFT changes in a dry year for 2-m temperature and 10-m wind; the response is larger in a wet year for 2-m water vapor mixing ratio, convective available potential energy, vertically integrated moisture fluxes and surface precipitation. For EFTs with high productivity and a weak seasonal cycle, the nearsurface temperature during the spring of 1988 and 1998 increased by as much as 1°C in the central and western portions of La Plata Basin. Additionally, for higher productivity EFTs, precipitation differences were generally positive in both dry and wet years, although the patterns are not uniform and exhibit certain patchiness with drier conditions. [ABSTRACT FROM AUTHOR]

La Plata Basin is shared by five countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay), which have fast growing economies in South America. These countries need energy for their sustainable development; hence, hydropower can play a very important role as a renewable clean source of energy. This paper presents an analysis of the current hydropower production and electricity demand in La Plata Basin (LPB), and it analyses the maximum and residual hydropower potential of the basin for a horizon of 30 yr (i.e. year 2040). Current hydropower production is estimated based on historical available data, while future energy production is deduced from the available water in the catchment (estimated based on measured hydrographs of the past years), whereas electricity demand is assessed by correlating existing electricity demand with the estimated population growth and economic development. The maximum and residual hydropower potential of the basin were assessed for the mean annual flows of the present hydrological regime (1970-2000) and topographical characteristics of the area. Computations were performed using an integrated GIS environment called VAPIDRO-ASTE released by the Research on Energy System (Italy). The residual hydropower potential of the basin is computed considering first that the water supply needs for population, industry and agriculture are served, and then hydropower energy is produced. The calculated hydropower production is found to be approximately half of the estimated electricity demand, which shows that there is a need to look for other sources of energy in the future. [ABSTRACT FROM AUTHOR]

Abstract: The aims of this paper were to study the biofouling and biodeterioration of photos and maps stored at Historical Archive of the Museum of La Plata (HAMP), Argentine, and two repositories of the National Archive of Cuba Republic (NARC) and to carry out the physiological characterization of the isolated fungi and bacteria. The role of the environmental microbiota in the biofouling formation was also studied. Microbial assemblages in the air were sampled by sedimentation technique while those on documents were sampled by swabbering. Biofilm formation and biofouling were monitored by scanning electron microscope (SEM). Large microbial assemblages were found at NARC archives with the prevalence of genera Aspergillus, Cladosporium and Penicillium, whereas at HAMP these values were lower, Penicillium was the only fungal genus detected. Most of the fungi degraded cellulose and produced pigments and acids, and all of the isolated bacteria had proteolytic and/or cellulolytic activity. In all cases, a higher concentration of viable bacteria than of fungi was isolated from documents. These results correlated with bacterial values detected in air at NARC repositories. However, this correlation cannot be observed at HAMP where Aspergillus, Penicillium and Talaromyces helicus (teleomorph of Penicillium) were isolated. It is the first time that the last genus is reported in documents. [Copyright &y& Elsevier]

The author reflects on the paper he presented at a conference in La Plata, Argentina in September 2004, on the topic of "The State and the Politics of Memory: Archives, Museums, and Education." His paper is about discourses and sites of public memory and history in Berlin, Germany. The theoretical dimension of the paper he gave argued for the persistent dialectic of memory and history, specifically for the sharpening of discourses of memory according to the rules of history. He was arguing against the appropriation of history by memory in the tradition of Pierre Nora, and for the infusion of memory qua raw material by historical reasoning in what he takes to be the central Freudian argument.

This article analyses how La Plata River Basin experts perceive the process of setting up the governance of transboundary waters and determines whether the principles of good governance are adhered to, as established by the Organization for Economic Co-operation and Development (OECD). A questionnaire was developed and submitted to experts with demonstrated expertise in the field. The results suggest that transboundary water governance needs to be strengthened. Critical issues include principles related to policy coherence and coordination among sectors, integrity and transparency, stakeholder engagement, and balanced commitments between consumers, rural and urban regions, and generations. [ABSTRACT FROM AUTHOR]

Framed within the theory and practice of social justice in English language teacher education (ELTE), the aim of this study was to foster pre-service teachers' awareness of social justice principles, issues and practices by taking part in a service learning experience during their higher education studies in a non-governmental organisation located on the outskirts of La Plata city in Argentina. In collaboration with their university tutors, three pre-service teachers taught workshops using intercultural literature in English during 2017–2018 for underserved children in the NGO. Data comprise four reflection logs written by each teacher candidate during 2017–2020, analysed using content analysis. Findings show the significance of providing an experientially grounded sense of social justice education. The study illustrates pre-service teachers' journeys toward social justice grounded in field work beyond the level of rhetoric. It also tests current perspectives on social justice in a South American setting, as work done on this basis has focused almost exclusively on Africa. Implications for ELTE and education in general are discussed. [ABSTRACT FROM AUTHOR]

This paper presents the first numerical cosmogenic ages of glacial deposits from the eastern slope of the Plata peak (6000) in the arid Central Andes (32° S). The moraines are distributed along three different valleys: Vallecitos, Angostura, and Las Mulas. In the first, only one moraine was identified and no blocks could be sampled for dating. The other two have evidence of two glacial advances, Angostura I and Angostura II. The advances Loma de los Morteritos I and II were recognised in the Las Mulas valley. In both cases, first and second advances are preserved at a similar altitude. Surface boulders on the top of moraines were sampled for Be 10 . Obtained ages are all similar and Late Pleistocene in age. They fit very well with local stratigraphy and regional paleoclimate evidence. The Loma de los Morteritos moraine II located at 3000 masl dated to ∼25,000 years. Ages of ∼8,000 and ∼12,000 years were found for the Angostura II deposit (∼3300 masl). An age was obtained for the outwash deposit identified along the El Salto valley (∼69,000 years) associated with a Late Pleistocene drift. Quantitative datings presented here improve knowledge about the glacial chronology of the Plata range and Quaternary stratigraphy of the Central Andes, even though they represent a maximum age for these glacial advances. New findings support the occurrence of two Late Pleistocene glacial advances, and an older one in the Blanco River valley. Adjusted ages around ∼8,000 and ∼25,000 years for younger stage could be evidence of the Last Glacial Maximum (LGM) period for this region. [ABSTRACT FROM AUTHOR]

This Research Note discusses a new methodological approach to the history of the Cuban Missile Crisis that approaches the event through the lens of a collection of communist and anticommunist pamphlets from an archive in La Plata, Argentina. It argues that the words and images contained in these documents reveal popular, non-government responses to the crisis. The pamphlets offer the opportunity to tell a new history that shifts the focus from superpower rivalry to local activism and global engagement. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic abruptly changed the classroom context and presented enormous challenges for all actors in the educational process, who had to overcome multiple difficulties and incorporate new strategies and tools to construct new knowledge. In this work we analyze how student performance was affected, for a particular case of higher education in La Plata, Argentina. We developed an analytical model for the knowledge acquisition process, based on a series of surveys and information on academic performance in both contexts: face-to-face (before the onset of the pandemic) and virtual (during confinement) with 173 students during 2019 and 2020. The information collected allowed us to construct an adequate representation of the process that takes into account the main contributions common to all individuals. We analyzed the significance of the model by means of Artificial Neural Networks and a Multiple Linear Regression Method. We found that the virtual context produced a decrease in motivation to learn. Moreover, the emerging network of contacts built from the interaction between peers reveals different structures in both contexts. In all cases, interaction with teachers turned out to be of the utmost importance in the process of acquiring knowledge. Our results indicate that this process was also strongly influenced by the availability of resources of each student. This reflects the reality of a developing country, which experienced prolonged isolation, giving way to a particular learning context in which we were able to identify key factors that could guide the design of strategies in similar scenarios. [ABSTRACT FROM AUTHOR]

Since the 19th century, it has been proposed that the wide geographic distribution of the Guaraní indigenous populations in large areas of South America was the result of prehistoric movements of large numbers of people through the main rivers of the La Plata Basin and the Brazilian coastline. However, no detailed spatial and temporal analysis has been carried out with the dated Guaraní archaeological sites of the different zones of Brazil, Argentina, and Uruguay. This is one of the reasons why some of the main ideas about this past population expansion still lack empirical validation. This paper presents a study on the geographic and temporal distribution of the Guaraní archaeological sites in the La Plata Basin and the Atlantic coast of southern Brazil. The overall purpose is to contribute to understanding the Guaraní expansion using the analysis of two basic archaeological variables: space and time. Based on available numerical dates ( 14 C and thermoluminescence) and the application of GIS software, potential dispersion routes are discussed. To date, more than 1100 archaeological sites assigned to the Guaraní, along with almost 250 numerical dates were analyzed. With this data, it was possible to elaborate a Dispersion Routes Model and a Temporal Visualization Model, which enabled identification of the sequence of population dispersal, with two main expansion pulses, throughout nearly two millennia of Guaraní movements across the South American Lowlands. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to reflect on the effects of the COVID-19 pandemic on education and draw some tentative assumptions from the information and experiences gathered from participants in this community about their possible impact on the future of education. Design/methodology/approach: This study uses a single-case descriptive case study that analyses some indicators of changes in teaching and learning that have taken place to date in the pandemic period as seen from Docentes en línea, a virtual community of practice of the Universidad Nacional de La Plata, Argentina. Findings: A number of shortcomings in the educational system, technological infrastructure and teacher formation in many of our members' countries. Concurrently, rising interest in the use of information and communication technology (ICT) in education and a new awareness of possible changes. Research limitations/implications: Part of the data comes from informal sources; therefore, they cannot be completely systematised or quantified. Besides, the results are provisional because the pandemic has not ended. Originality/value: This analysis was conducted on the basis of first-hand data collected in the activity developed by the members of this virtual community of practice. There is little research on this type of activity at the moment. [ABSTRACT FROM AUTHOR]

There is an increasing demand for future climate scenarios, particularly for impact studies. In this study, simulation outputs taken from a set of three regional climate models (RCMs) are used to force a hydrologic model to derive future streamflow scenarios for La Plata Basin. As RCMs have biases in their mean precipitation and temperature fields, a statistical scheme is previously used to remove the systematic part of the bias. Future hydrologic scenarios were derived considering two future periods: 2021–2040 (near future) and 2071–2090 (far future). In terms of climate projections, RCMs predict warmer conditions in almost the whole basin, while precipitation variations are not uniform in sign across the region but overall tend to be positive over the southern part of the basin. Nevertheless, a trend towards a gradual increase in streamflow was found for the majority of the rivers in the basin particularly for the near future followed by less uniform variations towards the end of the present century. Future changes in the largest monthly streamflow are similar to those in the mean values, with also some differences among RCMs and on the period and sub-basin considered. [ABSTRACT FROM PUBLISHER]

Abstract: This paper describes the ‘Prof. Dr. Rómulo Lambre’ skeletal collection. The Lambre Collection is housed in the School of Medical Sciences of the National University of La Plata and it consists of skeletal remains ceded by the Municipal Cemetery of La Plata. The collection has more than four hundred skeletons, with information on age, sex, nationality, date and cause of death. It was created for teaching and research purposes in compliance with current legislation, and its management meets guidelines specified in the Declaration of the Argentinian Association for Biological Anthropology on . [Copyright &y& Elsevier]

Water resources management and agriculture planning models require a statistical synthesis of some rainfall features, in particular those representing dry atmospheric conditions. The bigger the basin, the more important these features become, as is the case of the La Plata Basin LPB.This paper focuses on the precipitation variability in the large LPB in South America, analysing the number of months per year with low rainfall and the sequences of months with low rainfall, their theoretical distributions and stability, which are needed as input for the models mentioned above.Long time series are used to analyse the lowfrequency variability and the relative importance of decadal variability. Changes are evident in the number of months per year with low rainfall, with a decrease of about 20 in the period after 1970.Theoretical distribution models binomial and geometric are fitted to these empirical distributions, and the regional variability of the fitting parameters is shown. In practically the entire region, the goodnessoffit of the two theoretical models considered is statistically satisfactory.The temporal variability of the parameters of the theoretical binomial p and geometric α distributions is analysed, in excluding subperiods of 10 and 5 years, respectively. The results show lowfrequency variability overlapped on a decadal variability, with low homogeneous regional behaviour.The distribution models have proven to be efficient for frequency adjustments of the rainfall properties studied. These results are an acceptable and necessary input to decision models in LPB. They also make it possible to infer effects of climate change. Copyright © 2008 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The close contact between dogs and humans creates the best bridge for interspecies transmission of antimicrobial-resistant bacteria. The surveillance of its resistance including the detection of extended-spectrum beta-lactamases (ESBLs) in Escherichia coli as indicator bacteria is an important tool to control the use of antimicrobials. The aim of this research was to evaluate the E. coli resistance in strains by phenotypic methods, isolated from pet and stray dogs of La Plata city, Argentina. Faecal samples were collected using rectal swabs from 50 dogs with owners (home dogs = HD) and 50 homeless dogs (stray dogs = SD). They were cultured in 3 MacConkey agar plates, with and without antibiotics (ciprofloxacin and cefotaxime). 197 strains were isolated, of which only 95 strains were biochemically identified as E. coli, 46 strains were from HD, and 49 were from SD. Antimicrobial susceptibility was evaluated by the Kirby–Bauer disk diffusion method. The most prevalent resistance was for tetracycline, streptomycin, and ampicillin. In both groups, the level of resistance to 3rd generation cephalosporins was high, and there were multiresistant strains. There was a higher level of antimicrobial resistance in strains from SD compared to HD. There were 8% of strains suspected of being ESBLs among samples of HD and 36% of SD. One (2%) of the strains isolated from HD and 11 (22%) from SD were phenotypically confirmed as ESBL. Pets and stray dogs are a potential source of E. coli antibiotic resistance in Argentina; therefore, its surveillance must be guaranteed. [ABSTRACT FROM AUTHOR]

This article details the case of the La Plata basin, a transboundary basin shared between Argentina, Bolivia, Brazil, Paraguay and Uruguay. By addressing some cases of disputes between local and state actors in the La Plata basin, we show that even with an institutional framework for cooperation and transboundary water management, conflicts and tension might remain between riparian states. [ABSTRACT FROM AUTHOR]

Copyright of Cultura Latinoamericana is the property of Universidad Catolica de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present work summarizes 10 years of field observations of an exurban squamate assemblage occupying a 1200 ha patch in the suburbs of La Plata City (Los Porteños, Buenos Aires, Argentina). Crossed by two streams (Martin and Carnaval), the area is characterized by intensive horticulture and floriculture, poultry and pig farming, exhibits a low housing density (1 house/ha), and the roads are largely unpaved. This area is under stress due to continuous expansion of the neighboring city in detriment of rural areas, determining a stressing environmental scenario. Field data were complemented and contextualized with museum records of the squamates present in the area and in neighboring departments of La Plata. The field-based species list of squamates from Los Porteños comprises one amphisbaenian (Amphisbaena darwinii = 26 specimens), five snakes (Paraphimophis rustica = 24, Xenodon dorbignyi = 6, Erythrolamprus poecilogyrus = 3, Erythrolamprus semiaureus = 2, Lygophis anomalus = 1), and one lizard (Salvator merianae = 11). The number of species of squamates in Los Porteños was higher than the expected compared with the species from surrounding areas. Fossorial, nocturnal and generalist species were the most abundant in Los Porteños. These urban adapter species lack dietary constraints and their living habits minimize the encounters with humans, who commonly kill them. [ABSTRACT FROM AUTHOR]

A new climatology of South Atlantic cyclones is produced to provide new insights into the conditions leading to genesis in different regions of the domain. Cyclones are identified and tracked based on the relative vorticity at 850 hPa computed from the NCEP-CFSR winds. The characteristics of the cyclones are obtained by diagnostic variables sampled within a radial distance from the cyclone centers to produce the spatial distribution of cyclone properties at the time of genesis. Also, cyclone centered composites are used to analyze the cyclone structure and evolution during their genesis. There are four main cyclogenesis regions in the South Atlantic Ocean: the Southern Brazilian coast (SE-BR, 30 ∘ S ), over the continent near the La Plata river discharge region (LA PLATA, 35 ∘ S ), the southeastern coast of Argentina (ARG, 40 ∘ S – 55 ∘ S ) and the Southeastern Atlantic (SE-SAO, centered at 45 ∘ S and 10 ∘ W ). We found that cyclogenesis northward of 35 ∘ S occurs mainly due to low-level forcing associated with moisture transport in the summer, and is associated with upper-level forcing in the winter due to a strong baroclinic environment. Southward of 35 ∘ S , cyclones develop in a high baroclinic environment throughout the year with only a small influence from moist processes. The cyclone composites reveal that SE-BR and SE-SAO cyclones are associated with secondary development, the LA PLATA cyclones development is influenced by an orographic low in their early stages, and ARG cyclones are influenced by thermal advection as an essential mechanism in the reduction of static stability. [ABSTRACT FROM AUTHOR]

The cultural properties kept in museums are exposed to different factors that may affect the integrity. The aims of the present study were i) to determine the environmental fungal load present both inside and outside the Egyptian Room of the Museum of Natural Sciences of La Plata, Argentina, as well as inside two showcases where Egyptian sarcophagi are preserved, along a one-year monitoring, and ii) to evaluate the possible impact of temperature and relative humidity on the preservation of these mummies. The fungal load was determined by means of a volumetric air sampling methodology and the environmental variables by means of specific instruments. The fungal load found in the four sites studied was of 32843,23 CFU/m3, belonging to 21 fungal taxa, mainly to the phylum Ascomycota. The most representative were Beauveria bassiana, Fusarium oxysporum, Penicillium sp. and Rhodotorula sp. (as a yeast representative), were common to the four sites, showing a significant similarity between the outdoor and indoor environments. The temperature of the exhibition room and that of the two showcases were either similar or lower than the values recommended by the UNI 10829:1999 standards. In contrast, throughout the year, the relative humidity recorded was higher than the recommended values. [ABSTRACT FROM AUTHOR]

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High aerosol loadings are discharged into the atmosphere every year by biomass burning in the Amazon and central Brazil during the dry season (July–December). These particles, suspended in the atmosphere, can be carried via a low-level jet toward the La Plata Basin, one of the largest hydrographic basins in the world. Once they reach this region, the aerosols can affect mesoscale convective systems (MCSs), whose frequency is higher during the spring and summer over the basin. The present study is one of the first that seeks to understand the microphysical effects of biomass burning aerosols from the Amazon Basin on mesoscale convective systems over the La Plata Basin. We performed numerical simulations initialized with idealized cloud condensation nuclei (CCN) profiles for an MCS case observed over the La Plata Basin on 21 September 2010. The experiments reveal an important link between CCN number concentration and MCS dynamics, where stronger downdrafts were observed under higher amounts of aerosols, generating more updraft cells in response. Moreover, the simulations show higher amounts of precipitation as the CCN concentration increases. Despite the model’s uncertainties and limitations, these results represent an important step toward the understanding of possible impacts on the Amazon biomass burning aerosols over neighboring regions such as the La Plata Basin. [ABSTRACT FROM AUTHOR]

After a flood which devastated the city of La Plata (Argentina) in April 2013, a survey of the water situation in the region revealed that relevant studies and projects related with this area were scattered and lacked visibility. This prompted academic, scientific, technologic, and governmental institutions to take action and work together to compile, organize, and disseminate available data in an unprecedented response to an environmental disaster in the region. For this purpose, a dedicated collection was created in the SEDICI, the institutional repository for the Universidad Nacional de La Plata, and subsequently, the Observatorio Medioambiental La Plata (OMLP), a repository for data on environmental research, was launched. This document describes these collaboration initiatives which aim to anticipate and reduce the impact of natural disasters, their main characteristics, their resources, and their current progress. Projects driven by the OMLP are also described, along with a description of their technical and infrastructure deployment as per the open access policies. [ABSTRACT FROM AUTHOR]

Warm-season precipitation variability over subtropical South America is characterized by an inverse relationship between the South Atlantic convergence zone (SACZ) and precipitation over the central and western La Plata basin of southeastern South America. This study extends the analysis of this 'South American Seesaw' precipitation dipole to relationships between the SACZ and large, long-lived mesoscale convective systems (LLCSs) over the La Plata basin. By classifying SACZ events into distinct continental and oceanic categories and building a logistic regression model that relates LLCS activity across the region to continental and oceanic SACZ precipitation, a detailed account of spatial variability in the out-of-phase coupling between the SACZ and large-scale organized convection over the La Plata basin is provided. Enhanced precipitation in the continental SACZ is found to result in increased LLCS activity over northern, northeastern, and western sections of the La Plata basin, in association with poleward atmospheric moisture flux from the Amazon basin toward these regions, and a decrease in the probability of LLCS occurrence over the southeastern La Plata basin. Increased oceanic SACZ precipitation, however, was strongly related to reduced atmospheric moisture and decreased probability of LLCS occurrence over nearly the entire La Plata basin. These results suggest that continental SACZ activity and large-scale organized convection over the northern and eastern sections of the La Plata basin are closely tied to atmospheric moisture transport from the Amazon basin, while the warm coastal Brazil Current may also play an important role as an evaporative moisture source for LLCSs over the central and western La Plata basin. [ABSTRACT FROM AUTHOR]

The mapping and forecasting of droughts and floods is an important potential field of application of global soil moisture and water storage products from satellites and models. Especially when extremes in near-surface soil moisture propagate into extremes in total water storage, agricultural production and water supply can be severely impacted. This study relates soil moisture from the WaterGAP Global Hydrology Model (WGHM) and the satellite sensors Advanced Microwave Scanning Radiometer—Earth Observing System (AMSR-E) and Advanced Scatterometer (ASCAT) to total water storage variations from the satellite gravity mission GRACE. A particular focus is on destructive hydrological extreme events, as listed in the International Disaster Database EM-DAT. Data sets are analyzed via correlation, time shift, and principal component analyses. The study area is the La Plata Basin in South America. The results indicate that most of the soil moisture anomalies are linked to periods of El Niño and La Niña and associated natural disasters. For the La Plata drought of 2008/2009 and the El Niño flooding of 2009/2010, soil moisture serves as an indicator for the later deficit or surplus in total water storage. These hydrological anomalies were strongest in the southern, central, and eastern parts of the basin, but more than one hundred thousand people were also affected in the northwestern part. [ABSTRACT FROM AUTHOR]

We analyze the local and remote impacts of climate change on the hydroclimate of the Amazon and La Plata basins of South America (SA) in an ensemble of four 21st century projections (1970-2100, RCP8.5 scenario) with the regional climate model RegCM4 driven by the HadGEM, GFDL and MPI global climate models (GCMs) over the SA CORDEX domain. Two RegCM4 configurations are used, one employing the CLM land surface and the Emanuel convective schemes, and one using the BATS land surface and Grell (over land) convection schemes. First, we find considerable sensitivity of the precipitation change signal to both the driving GCM and the RegCM4 physics schemes (with the latter even greater than the first), highlighting the pronounced uncertainty of regional projections over the region. However, some improvements in the simulation of the annual cycle of precipitation over the Amazon and La Plata basins is found when using RegCM4, and some consistent change signals across the experiments are found. One is a tendency towards an extension of the dry season over central SA deriving from a late onset and an early retreat of the SA monsoon. The second is a dipolar response consisting of reduced precipitation over the broad Amazon and Central Brazil region and increased precipitation over the La Plata basin and central Argentina. An analysis of the relative influence on the change signal of local soil-moisture feedbacks and remote effects of Sea Surface Temperature (SST) over the Niño 3.4 region indicates that the former is prevalent over the Amazon basin while the latter dominates over the La Plata Basin. Also, the soil moisture feedback has a larger role in RegCM4 than in the GCMs. [ABSTRACT FROM AUTHOR]

Water resources availability presents a high degree of uncertainty in the context of climate change. In this study, the multi-year variability of simulated streamflow for three rivers (Paraná, Uruguay and Negro) in the La Plata Basin (LPB) in the period 1991–2098 is analysed. Simulated streamflow for that period were produced in a two-stage process involving a regional climate model (RCM) and a distributed hydrology model (VIC (variable infiltration capacity)). Outputs from two RCMs (PROMES [Spanish acronym for mesoscale forecast] and RCA [Rossby Centre regional atmospheric climate model]) were used in order to assess the sensitivity of the results to different models. Various spectral methods (singular spectrum analysis, maximum entropy method and multi-taper method) were used in order to detect low-frequency variability modes and preferred quasi-periodicities for annual and seasonal simulated time series. Both simulations generate larger runoff for the twenty-first century than those observed for the twentieth century for the three rivers. For annual time series, the variability in timescales longer than 30 years is detected by one of the simulations for the three rivers, and only weakly for the Negro River in the other. Seasonal variations of the preferred modes of multi-annual variability are apparent. The River Paraná shows a persistent 10-year period during most of the year in the PROMES-VIC simulation. No LFV modes were found for any trimester in any river for PROMES-VIC, while for RCA-VIC simulations, these appeared in austral summer (Negro and Uruguay rivers) or early winter (Paraná River). A striking finding, both for annual and seasonal simulated time series, is the conspicuous presence of pseudo-periods in the 2.5–5 years band that had already been captured in the observed 20th streamflow time series [Maciel, F., Díaz, A., and Terra, R., 2013. Multi-annual variability of streamflow in La Plata Basin. Part I: observations and links to global climate.International Journal of River Basin Management, 11 (4), 345–360.]. This pattern is probably linked to the El Niño–Southern Oscillation (ENSO) phenomenon. These results imply that the well-known relationships between ENSO and precipitation and streamflow anomalies in the LPB are expected to prevail during the twenty-first century. [ABSTRACT FROM PUBLISHER]

Distributions of monthly rainfall averaged spatially over three regions of the La Plata Basin (LPB) were projected for 2011–2040 and 2071–2100 using outputs of four regional climate models (RCMs) nested in three different general circulation models, run with the SRES A1B emission scenario. Tuning of simulations with observations was done at the control period 1981–1990. During the past 50 years, in part of LPB, there was a positive trend in annual precipitation. Two of the models indicate the maintenance of this trend over the northeast of Argentina and south of Brazil, while over the southernmost region of LPB, all models show increasing precipitation throughout the twenty-first century. Trends are less ambiguous for extreme precipitation, especially in the southernmost part of LPB, where huge and long-lasting floods take place over plains with small drainage. Months with extreme precipitation in LPB present a pronounced annual cycle with higher frequency from October to April. According to the RCM projections, this pattern would persist during the twenty-first century. Although, other factors cannot be discarded, the projected trends towards higher extreme monthly precipitation seem to be caused by an increase in the moisture convergence in the lower atmosphere over the east of LPB. [ABSTRACT FROM PUBLISHER]

La Plata basin is one of the most important agricultural and hydropower-producing regions in the world. Extreme climate events such as cold and heat waves and frost events have a significant socioeconomic impact. This work analyzes the influence of the surface circulation in southern South America on daily maximum temperature TMAX and daily minimum temperature TMIN in southern La Plata basin. A Z test for the comparison of mean values and a Kolmogorov-Smirnov test for the comparison of distributions of TMAX and TMIN associated with each circulation pattern were performed. Specific daily surface circulation types are found to contribute to TMAX and TMIN anomalies and to have a predominant occurrence in the development of the extreme temperature events in the region. The TMAX spatial response to the regional low-level circulation is more homogenous and extended than is the response of TMIN. [ABSTRACT FROM AUTHOR]

Ten years of Tropical Rainfall Measuring Mission precipitation radar data are used to study the physical properties of the precipitating cloud systems that account for the summer rainfall of tropical and subtropical South America. Radar echoes in the continental subtropics tend to be of an intensely convective nature, especially at the eastern foothills of the Andes where diurnally forced deep convective cells of small horizontal scale form when moist low-level flow is driven toward the foothills in connection with a midlatitude disturbance. As the disturbance moves east over the La Plata basin, nocturnal convective systems of larger horizontal scale with wide stratiform regions occur in a zone of general convergence. Precipitation in the continental tropics is generally produced by convective systems with greater stratiform composition. At the northeastern foothills of the central Andes, radar echoes of nocturnal convective systems of medium to large horizontal scale occur where moist low-level flow is lifted over the foothills. Growth of systems to large size is inhibited by daytime divergence at the foothills. Over the Amazon basin, daytime systems are also smaller than nocturnal systems. Radar echoes of precipitation over the Brazilian Highlands are generally smaller in horizontal scale, more convective, and mostly occur during the afternoon over elevated terrain. In the oceanic South Atlantic convergence zone, radar echoes grow to extremely large sizes. They are highly stratiform in nature and occur during all times of the day except late evening when convergence is weakened as a response to continental heating. [ABSTRACT FROM AUTHOR]

Positive trends in annual rainfall in the La Plata Basin (LPB), south of 20°S observed in the last four decades of the twentieth century were not reversed and became more statistically significant when calculated until 2005. These trends were part of a more general change in the monthly precipitation distribution including extreme precipitation. Precipitation in dry and extremely dry months (below the 35th percentile) has been decreasing in the whole LPB region south of 22°S. On the contrary, precipitation in the above normal (between the 65th and 90th percentile) and the extremely high rainfall (above the 90th percentile) ranges has been increasing accounting for most of the annual precipitation trends. More than a steady trend, there has been an abrupt change in extreme monthly precipitation concentrated between 1977 and 1983. The analysis of intensity and frequency of extreme events was done fitting Generalized Extreme Values (GEV) and Poisson distributions. Each distribution was fitted with and without trends in the location parameter and tested to determine the best fit in each case. The regions where GEV with a positive trend was the best fit coincide with areas affected by extensive floods during the last decades. Spatially aggregated results highlight the signal of change towards higher maximum monthly precipitations for a wide span of return periods. The atmospheric circulation associated with cases where extreme monthly precipitation was observed in most of the stations was studied through the integrated water vapour transport in the lower troposphere and its associated divergence. During warm months, an intense northern low-level water vapour flow with two convergence nuclei, one over eastern Argentina, southern Brazil and Uruguay, and the other over western Argentina, along with a weakened south Atlantic Convergence Zone was associated with the more extreme precipitation months favouring the occurrence of Mesoscale Convective Systems. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

El artículo presenta diez nuevos registros de ácaros del suborden Oribatida encontrados en suelos de bosques urbanos de la ciudad de La Plata, Argentina. Los autores ofrecen una descripción de las especies estudiadas, la cual incluye la distribución geográfica en Argentina y hábitat conocido así como referencias previas.

Objective: Bone mineral density (BMD) loss has been described in adult women in the 12-month postpartum period. However, little is known about the precise BMD pattern in adolescent mothers. The present study aimed to evaluate BMD in Argentinean adolescent mothers followed up during the 12-month postpartum period. Design: Analytical, prospective clinical trial. BMD and body composition were determined by dual-energy X-ray absorptiometry; bone mineral content (BMC) and BMD were measured in the lumbar spine (L2-L4), femoral neck (FN), femur trochanter (TR), total hip (TH) and total body. Changes in BMD and BMC were analysed using ANOVA for pairwise comparisons. Other comparisons were performed with the paired-sample t test and Wilcoxon test; Pearson's correlation coefficient was used to analyse the relationship among continuous variables. Setting: La Plata, Argentina. Subjects: Adolescent mothers (n 35; 17 years old or less) were recruited within 15 d after delivery. Studies and follow-up were performed at 15 d and 3, 6 and 12 months postpartum. Results: BMD and BMC losses at 3 and 6 months and recovery at 12 months fitted a quadratic curve (ANOVA) at the three sites studied (FN, TH, TR), in total-body BMD (P=0·000) and BMC (P=0·038). At hip sites, BMD loss occurred at 3 months (FN, P=0·000; TR, P=0·000; TH, P=0·000) and 6 months (FN, P=0·000; TR, P50·000; TH, P=0·000) compared with basal values. Percentage BMD loss immediately after delivery up to 6 months was about 5%. Conclusions: Adolescents showed significant BMD and BMC losses at 6 months postpartum, with an almost total recovery at 12 months in all sites studied. [ABSTRACT FROM AUTHOR]

This study presents a multitemporal climatology of water excess and shortage during the 20th century in the La Plata Basin. The climatology is based on 0.5 × 0.5 grid across the region. We transform monthly precipitation series for each point into index series at different time scales using the Standardized Precipitation Index (SPI). A month is under water excess (shortage) conditions at different time scales ( i = 6, 9, 12, and 18 months), when SPI[ i]( j) > 1.5 (SPI[ i]( j) < 1.5), where j is the current month. Trends in precipitation were determined using mean regional series of average values over the entire basin. A month when more than 30% of the total basin is under water excesses (shortages) is defined as an excess (shortage) critical month. From the vulnerability point of view, we analyzed the occurrence of critical months. The number of excess critical months increase with time scale of index, and almost all the critical months occurred after 1950 as a consequence of the low-frequency precipitation pattern. That means a noticeable increase in the vulnerability to extended excesses (more than 30% of the area under water excesses) after 1950, especially over the Upper Paraná and the Uruguay basins. For shortage critical months, the behavior depends on time scales. At large time scale (18 and 12 months), almost all the shortage critical months occurred in the period 1901–1950 and only at shorter time scale (9 and 6 months), some critical months appeared after 1950. That means a noteworthy decrease in the basin vulnerability to extended water shortage after 1950 and a moderate decrease in vulnerability to generalized shortage. If we analyze the frequency and mean duration of water excess and shortage events across the basin, we can appreciate that there is a tendency to relate higher frequency regions with regions with lower mean duration events, and conversely. [ABSTRACT FROM AUTHOR]

The city of La Plata and its surroundings are a very populated area, which has an important Industrial Pole and intense traffic activity but environmental studies have been rare so far. This article presents and discusses the importance of wind frequencies and velocities for the transport of air pollutants. The study emphasizes the importance of knowing wind patterns on an hourly basis that can be helpful for designing a monitoring network as well as for preventing exposure to pollutants. Correlation between monthly SO2 concentrations and wind frequencies and velocities are discussed for a particular set of directions NNW–NE that carry pollutants from industrial sources toward populated areas. As a result, averaged wind frequencies have been found to be very important for determining patterns influencing pollutants transport; the influence of averaged velocities has shown low variability (hourly and monthly). Hierarchical cluster analysis applied to wind roses provided a useful approach for analyzing and describing the general daily occurrence of winds. [ABSTRACT FROM AUTHOR]

This article presents and discusses SO2 air quality concentrations (ppbv) together with wind velocities and directions measurements carried out between September 1st and December 21st 2005 at a site located 8.5 km away from the Industrial Pole of La Plata area. As the city and its surroundings have no official monitoring network, the current work enlarges the air quality information available from the zone and sets some initial considerations to the future siting of monitoring stations. The statistical analysis of the data was performed using techniques of tests for outliers and trends, dissimilarity measures and robust regression. In relation to SO2 concentrations, low values were found during this short campaign considering daily averages (with a maximum of 8.5 ppbv) and hourly averages (with a maximum of 25.9 ppbv); World Health Organization guidelines were never surpassed. Nevertheless, a strong dependence between wind directions carrying air pollutants from the Industrial Pole and hourly concentration peaks were found. Due to low monthly SO2 concentrations and because a decreasing time trend was found, the authors propose, as an example, the implementation of an alternative discontinuous method to the continuous analyzer used in the current campaign. Our results state that sampling every 7 days at 13:00–13:59 hours (local time) would be enough to get representative values of the air quality. As a general remark it is possible to highlight that longer and systematic studies should be encouraged to confirm the seasonal wind pattern and to evaluate the air quality. [ABSTRACT FROM AUTHOR]

This article presents and discusses SO2 (ppbv) concentration measurements combined with meteorological data (mainly wind speed and direction) for a five-year campaign (1996 to 2000), in a site near an oil refinery plant close to the city of La Plata and surroundings (aprox. 740.000 inh.), considered one of the six most affected cities by air pollution in the country. Since there is no monitoring network in the area, the obtained results should be considered as medium term accumulated data that enables to determine trends by analyzing together gas concentrations and meteorological parameters. Preliminary characterization of the behaviour of the predominant winds of the region in relation with potential atmospheric gas pollutants from seasonal wind roses is possible to carry out from the data. These results are complemented with monthly averaged SO2 measurements. In particular, for year 2000, pollutant roses were determined which enable predictions about contamination emission sources. As a general result we can state that there is a clear increase in annual SO2 concentration and that the selected site should be considered as a key site for future survey monitoring network deployment. Annual SO2 average concentration and prevailing seasonal winds determined in this work, together with the potential health impact of SO2 reveals the need for a comprehensive and systematic study involving particulate matter an other basic pollutant gases. [ABSTRACT FROM AUTHOR]