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Argentina is a Latin American country which encounters soil degradation problems. The most productive regions have implemented conservative land practices (no-till). However, agricultural frontier has been displaced to marginal lands with arid and semiarid climates, with the consequent disappearance in many areas of native forest and land degradation. In this work, the fallout of gamma-emitting radionuclides, 137Cs and 7Be, was jointly used to assess changes in soil erosion in a recently converted semiarid ecosystem into agricultural land. 137Cs was utilized to estimate the erosion over the past 60 years, whereas 7Be was employed to estimate the erosion after the conversion of the area to cultivated land and soil tillage. For 137Cs the Proportional Model (PM), the Mass Balance Model II (MBMII) and the MODERN model were used, for 7Be the Profile Distribution Model (PDM) and the MODERN model were used. 137Cs indicates mean erosional rates of 8.2, 10.5 and 6.5 Mg ha−1 a−1, using MBMII, PM and MODERN, respectively, and that a soil layer between 0.5 and 0.8 mm was annually lost by erosion. By applying a 7Be tracer, we measured erosion rates of 2.4 and 3.3 Mg ha−1 (with PDM and Modern, respectively), indicating the loss of the upper 0.2 mm of soil. This erosion can be attributed to a few heavy rainfalls that occurred within the past 90 days. The results suggest that current land management practices have led to an increase in soil erosion. This could be attributed to the fact that the soil remains bare after crop harvest, which may compromise its conservation and future productivity. [ABSTRACT FROM AUTHOR]

Copyright of Psocial is the property of Revista de Investigacion en Psicologia Social 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.)

There is a global trend toward intensive livestock breeding, which tends to increase the microbial load in the environment as well as the presence of volatile compounds and dust that can cause health issues. Cattle is the major producer of Escherichiacoli (E. coli), a group of foodborne bacteria associated with severe human diseases, and Neuquén province in Argentina has one of the highest rates of uremic hemolytic syndrome incidence in the world. This paper presents the results of two sampling events of E. coli bacteria at 39 sites in La Paisana ranch (LPR), in Añelo (Neuquén), considering locations inside the pens, upwind, and downwind of the feedlot with different time steps, using a Microflow α equipment. The ranch has approximately 600 heads and clean and controlled installations. The field experiment included sampling airborne aerosol deposition and concentration using passive and active methods. Concentrations were also estimated using an atmospheric dispersion model. During the field experiment, counts of up to 2970 CFU/m3 were obtained in the cattle stockyards and up to 111 CFU/m3 at a distance of 100 m. [ABSTRACT FROM AUTHOR]

Most of the validated 'events exposure' questionnaires are focused on lifetime burden and are hardly applicable to Argentina owing to its sociocultural and natural conditions, where corruption and economic crises have been hitting middle-class people's lives in a cyclic manner. This prompted us to develop a new questionnaire, validated in Argentina, to assess the occurrence of exposure to events and their severity over a limited period. Deductive (bibliographic search) and inductive (by a Delphi group) selection was used to create an initial group of 24 questions, which were condensed into a final 14-item questionnaire. After administration to 512 inhabitants of the metropolitan area of Buenos Aires and other major cities in Argentina, the questionnaire was shown to have an intraclass correlation coefficient of 0.996 and an internal consistency, measured by the omega coefficient, of 0.86. Because this study was conducted during the coronavirus disease 2019 (COVID-19) pandemic, an additional question on how this situation affected individuals was included. The time span used to measure event exposure was 1 year prior to the study. In the case of an affirmative event exposure, the responder selected the severity of the stress perception generated on a Likert-like scale, ranging from 0 (nothing) to 5 (severe). Fifty-eight per cent of the responders were women, and the mean age was 47.14 years (SD: 13.97). The average annual event incidence per person was 2.5 events (SD: 1.88). Thirty-two per cent (164/512) reported at least one 5-point event on the severity scale. Ten per cent (51/512) responded that the COVID-19 pandemic affected them in a different manner than events related to personal or family disease, or the death of a close family member or friend. Stressful or potentially traumatic events in Argentina's middle class are different from those reported in other countries, which drove us to create and validate a specific 14-item event exposure questionnaire with the addition, in the current context, of a COVID-19-related question. [ABSTRACT FROM AUTHOR]

Copyright of Revista Argentina de Cardiología is the property of Sociedad Argentina de Cardiologia 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.)

Copyright of Revista Internacional de Ciencias Sociales Interdisciplinares is the property of Common Ground Research Networks 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.)

Buenos Aires city is located near the southern limit of the distribution of Aedes aegypti (Diptera: Culicidae). This study aimed to assess long-term variations in the abundance of Ae. aegypti in Buenos Aires in relation to changes in climatic conditions. Ae. aegypti weekly oviposition activity was analyzed and compared through nine warm seasons from 1998 to 2014, with 200 ovitraps placed across the whole extension of the city. The temporal and spatial dynamics of abundances were compared among seasons, and their relation with climatic variables were analyzed. Results showed a trend to higher peak abundances, a higher number of infested sites, and longer duration of the oviposition season through subsequent years, consistent with a long-term colonization process. In contrast, thermal favorability and rainfall pattern did not show a consistent trend of changes. The long-term increase in abundance, and the recently documented expansion of Ae. aegypti to colder areas of Buenos Aires province suggest that local populations might be adapting to lower temperature conditions. The steadily increasing abundances may have implications on the risk of dengue transmission. [ABSTRACT FROM AUTHOR]

Abstract: This paper evaluated the growth performance of Criollo kids under three different rearing systems and determine the economic profit of each rearing systems with slaughter at two different ages. Forty-eight kids were distributed randomly into three groups (n =16). Two groups of kids were naturally reared with their mothers, suckling goat milk until weaning at 30 and 45days of age (groups N30 and N45, respectively). In the remaining group, kids were artificially reared on milk replacer until 45days of age (group A45). Between 30 and 90days, all groups were ad libitum offered with a ration of alfalfa hay and ground corn. Kids from each group were slaughtered at 60 (n =8) and 90 (n =8) days old. The growth performance of kids was acceptable achieving average daily gain (ADG) values ranging between 115.9 and 129.5gd−1, with no major differences between rearing systems at the end of the study. The natural rearing systems showed low values of gross return, which ranged from −0.60 to 5.67US$kid−1, while the artificial rearing system was not economically viable due to the high cost of milk replacer and high demand of labor. The price of milk replacer should not exceed 20% of meat value so that artificial rearing becomes economically feasible. The average gross return of the two natural rearing groups slaughtered at 90days (3.96±1.46US$kid−1) was three times higher than the animals slaughtered at 60days (1.25±0.93US$kid−1). On the basis of the economic results it would be advisable to raise the kids naturally with goat milk and increase the age of slaugther, as long as consumers accept these older animals without decreasing the selling price of meat. [Copyright &y& Elsevier]

Intradiurnal variation of arboreal pollen (AP) in Mar del Plata city is compared during three non - consecutive years of survey and described in relation to the associated weather. The daily pattern of pollen abundance has a maximum between 10:00 and 12:00 h, while a minimum occurs at 18:00 h. The first two years of survey showed homogeneous daily trends, but in 1995 the maximum and minimum concentrations were delayed because of the change in position of the collecting station. Arboreal pollen spectrum presented qualitative and quantitative changes in the three years analysed. Results indicate optimal conditions for diurnal dispersion of arboreal pollen are high temperatures and low relative humidity. Also interaction between source position and wind direction has important effects on the timing of the peaks of some pollen types. [ABSTRACT FROM AUTHOR]

AimTo study the relation between vegetation and pollen spectra as a basic information for the interpretation of Quaternary paleoenvironments. LocationSouthern Argentina between latitude 38–47° S and longitude 62–72° W. MethodsPollen analysis, statistical analysis, geographical information system (GIS). ResultsResults of cluster analysis of pollen surface samples show close relations between the dispersal and composition of pollen taxa in the spectra with the corresponding vegetation formations. First isopoll maps of this region presented here by using GIS, demonstrate the relation between the main pollen taxa, the vegetation and the mean annual precipitation. Main conclusionsThe results prove the usefulness of the method of ‘modern analogues’ for southern Argentina. [ABSTRACT FROM AUTHOR]

This work describes the facies architecture, morphology and textures of a Jurassic rhyodacitic cryptodome outcropping in the Don Nicolás Mine, an important Au–Ag producing mine located in the Deseado Massif, Argentinean Patagonia. The access to 70 m deep surface mining operation and to a large number of diamond drill cores offer a unique chance to explore the volcanic rock assemblage of this body, allowing to study intrusion and growth mechanisms of a shallow subvolcanic body, and also providing insights into the timing between different brecciation processes occurring during magma intrusion into a poorly consolidated and water saturated pyroclastic sequence. Facies analysis allowed to infer this body as the result of a rhyodacitic magma intruding in a single and steady endogenous inflation pulse, resulting in the development of a flow banded core and a fluidal peperite envelope due to the combination of relatively low magma viscosities (for a rhyodacitic melt), the development of stable vapor films insulating the flowing magma and also allowing the ductile deformation of the rhyodacite clasts, and the fluidization of the unconsolidated and water saturated host rocks. After the main inflation stage stopped, the collapse of the vapor films resulted in quench fragmentation modifying the originally fluidal shape of many clast at the peperites, specially at the outer portion of the breccia envelope where fluidal clast shapes were almost completely erased due to this process. At the same time water invaded the inner portions of the intrusion, causing widespread quenching and the development of intrusive hyaloclastites at the edges of the coherent facies. Image 1 [ABSTRACT FROM AUTHOR]

The aim of this study was to understand the benefit of diet mixing for Creole goats grazing native forage species in the central Monte desert of Argentina and the drivers of preference in the mixed diet. To achieve this goal, cafeteria-style experiments were conducted with thirty female Creole goats (2 years old; 44 ± 1.4 kg) and forage species that are typically ingested by goats in this region: Two tanniniferous ( Tricomaria usillo , Mimosa ephedroides ) and three non-tanniniferous shrubs ( Prosopis flexuosa , Capparis atamisquea, Atriplex lampa ). In Experiment 1, goats were assigned to three groups ( n = 10); two groups were offered single tannin-containing shrubs as their basal diet ( T. usillo ; SDTU or M. ephedroides , SDME), whereas the third group received a combination of all five forages (Mixed diet of forages, MD). After a fifteen-day adaptation period, half the animals in each group ( n = 5) were dosed with polyethylene glycol (PEG), a polymer that neutralizes the negative effects of tannins, whereas the other half (Control) were not dosed (CG). Daily dry matter intake (DMI), in vivo apparent digestibility of the diet (ADD) and nitrogen (ADN) were determined. For goats fed MD, preference was estimated based on the DMI of each of the forages offered. Jugular blood samples were collected on the first and last days of the experiment to determine concentrations of blood urea nitrogen (BUN) and serum metabolites indicative of liver damage. In experiment 2, intake rates (IR) of the five forage species were estimated. No significant differences in DMI were detected among treatments. However, goats offered a choice of forages (MD) in the CG treatment had greater diet digestibility and lower BUN than animals fed the single shrubs, showing evidence of a nutritional benefit with dietary diversity. Goats changed their foraging preferences in response to PEG supplementation. Animals in the CG treatment preferred M. ephedroides whereas animals in the PEGG treatment preferred A. lampa. There was a positive correlation between forage preference and IR of crude protein ( r = 0.65; P < 0.001) in PEGG goats, and between forage preference and IR of total tannins ( r = 0.77, P < 0.001) in CG goats. When PEG attenuated biological effects of condensed tannins, goats switched their preference from forages that offered the greatest IR of total tannins (i.e., M. ephedroides ) to those that led to the greatest IR of crude protein (i.e., A. lampa ). In summary, a mixed diet led to greater nutritional benefits than single diets, which contribute to explain the diverse array of food items goats typically show when browsing in the central Monte desert of Argentina. Our results also show that CP, tannins and plant structure (which offer variable intake rates) play significant roles in goats’ foraging preferences in this environment. [ABSTRACT FROM AUTHOR]

Abstract: The botanical composition of the diet and species preference of grazing goats in different physiological states were evaluated in the autumn and winter seasons. The study was performed in a desert rangeland in the northeast (NE) Mendoza region in Argentina. Food availability was estimated from forage species cover. Rectal grab faecal samples were collected from goats, and the botanical composition of the goat diet was determined using a microhistological technique. Goat preferences for each species consumed were calculated based on Ivlev''s index. Nutritional composition and secondary compounds of forage species were determined. Correlations between diet and availability; and between goat preference and nutritional composition of forage species were also estimated. The habitat consisted of a dominant woody stratum associated with an herb stratum primarily composed of grasses. Goats in different physiological states utilised a significantly higher proportion of woody vegetation compared to grass (p <0.01). When grass availability was high (autumn), the herb stratum was more utilised by pregnant and lactating goats than by dry goats (p <0.05). In the winter, the diet of lactating goats consisted of more Atriplex lampa compared to the diet of dry goats (p <0.05), probably due to the high crude protein content of the plant. Goats consumed forage species with highly variable total phenol and tannin contents, which did not negatively affect selection. Correlations between diet and availability were high in the winter for dry (r s =0.88, p <0.02), pregnant (r s =0.93, p <0.01) and lactating goats (r s =0.97, p <0.01) but were not significant in the autumn. A significant correlation between preference and crude protein was shown during the autumn season for pregnant and lactating goats (r s =0.6, p <0.05). Forage availability was the main factor influencing diet selection in this arid environment. When food availability was not a limiting factor, goats selected a diet that most closely matched their nutritional requirements. Physiological state modified nutrient requirements and affected diet selection in that pregnant and lactating goats selected forage species with high protein contents. [Copyright &y& Elsevier]

Abstract: In arid and semiarid regions of Central West Argentina, paleoenvironmental conditions and history of the Holocene vegetation is still scanty. This paper presents the analysis of palynological records of two Mid- to Late Holocene alluvial sequences (La Escala -LES- and Brazo Abandonado -BA-) in the fluvial basin of the Arroyo La Estacada (33°27′S and 69°03′W), placed in the Cordillera Frontal central piedmont of Mendoza province. Variations in pollen assemblages of the two sequences related to the environments developed in the floodplains of the arroyo allowed us to infer the evolution of local plant communities. Between the ca. 4000 and 3000 14C years BP and between ca. 500 and 400 14C years BP, a larger representation of hydrophytic communities related to environments with local water availability was inferred; and between ca. 3000 and 500 14C years BP an increase in shrubby xerophytic communities related to environments with lower water availability was detected. These results led us to propose that the Holocene pollen spectra fluctuations observed in the alluvial sedimentary sequences prove mainly changes in plant communities of the floodplain environment in response to the fluvial dynamics of the arroyo. [Copyright &y& Elsevier]

This research presents a qualitative study based on individual and group interviews, discussion groups, and document analysis that inquired about school principal's and administrators tasks around curricular changes in the elementary school level. The inquiry emphasis was about their decisions made on teaching. It was necessary to reconstruct the historical dynamic through which Tierra del Fuego's (Ushuaia) educational system was constituted. Although at first it was considered that the historic aspect was secondary to the contemporary aspect, the former acquired such importance that it caused a turn in the original proposal. As a result two studies can be clearly distinguished: One that is centred on the historic dimension (Study 1) and another one centred on the contemporary aspect (Study 2). One peculiarity of this investigation is the incorporation of teachers in training in the activities of Study 1. Even though Study 2 requires new elaborations, it can be said as a conclusion that it's decisive to inscribe the decision making of contemporary school principals in a historic retrospective. This will help us see the logics that were/are decisive in such decision making and directed their work; one that's marked by continuities and changes in a scenery of vertiginous demographic growth and personal rotation. [ABSTRACT FROM AUTHOR]

Background Intestinal failure (IF) patients received parenteral nutrition (PN) as the only available therapy until intestinal transplantation (ITx) evolved as an accepted treatment. The aim of this article is to report the long-term outcomes of a series of ITx performed in pediatric and adult patients at a single center 9 years after its creation. Patients and Methods This is a retrospective analysis of the ITx performed between May 2006 and January 2015. Diagnoses, pre-ITx mean time on PN, indications for ITx, time on the waiting list for types of ITx, mean total ischemia time, and warm ischemia time, time until PN discontinuation, incidence of acute and chronic rejection, and 5-year actuarial patient survival are reported. Results A total of 42 patients received ITx; 80% had short gut syndrome (SG); the mean time on PN was 1620 days. The main indication for ITx was lack of central venous access followed by intestinal failure–associated liver disease (IFALD) and catheter-related infectious complications. The mean time on the waiting list was 188 days (standard deviation, ±183 days). ITx were performed in 26 children and 14 adults. In all, 32 procedures were isolated ITx (IITX); 10 were multiorgan Tx (MOT; 3 combined, 7 multivisceral Tx (MVTx), 1 modified MVTx and 2 with kidney); 2 (4.7 %) were retransplantations: 1 IITx, 1 MVTx, and 5 including the right colon. Thirteen patients (31%) received abdominal rectus fascia. All procedures were performed by the same surgical team. Total ischemia time was 7:53 ± 2:04 hours, and warm ischemia time was 40.2 ± 10.5 minutes. The mean length of implanted intestine was 325 ± 63 cm. Bishop–Koop ileostomy was performed in 67% of cases. In all, 16 of 42 Tx required early reoperations. The overall mean follow-up time was 41 ± 35.6 months. The mean time to PN discontinuation after Tx was 68 days ( P = .001). The total number of acute cellular rejection (ACR) episodes until the last follow-up was 83; the total number of grafts lost due to ACR was 4; and the total graft lost due to chronic rejection was 3. At the time of writing, the overall 5-year patient survival is 55% (65% for IITx vs 22% for MOT; P = .0001); 60% for pediatric recipients vs 47% for adults ( P = NS); 64% when the indication for ITx was SG vs 25% for non-SG ( P = .002). Conclusions At this center, candidates with SG, in the absence of IFALD requiring IITx, showed the best long-term outcomes, independent of recipient age. A multidisciplinary approach is mandatory for the care of intestinal failure patients, to sustain a rehabilitation and transplantation program over time. [ABSTRACT FROM AUTHOR]

Abstract: Laguna Las Vizcachas is a cirque lake located at the margin of an extra-Andean volcanic plateau in southern Patagonia, Argentina, within the area of steppe and semi-desert east of the Andes. The number of paleoenvironmental records is still limited in this region. Sediments of this lake were studied in order to obtain multi-proxy information about the paleoenvironmental history of this site for the ‘Medieval Climate Anomaly’ and the ‘Little Ice Age’ chronozones. In combination with results from other sites across southern Patagonia, our data enhance the understanding of spatial patterns of past hydrological changes and contribute to distinguishing between the signals of temperature and precipitation. As Laguna Las Vizcachas is situated at 1100 m a.s.l. in a cool ‘mountain climate’, the lake system is more sensitive to changes of temperature and winter ice cover than other sites from lower elevations in this region. Our interpretation of the multi-proxy dataset is based on signals of clastic sediment input, lake productivity, organic matter sources and preservation, dilution effects and early diagenetic overprint. The record reveals a period of enhanced fluvial runoff resulting from higher precipitation from the 12th until the end of the 14th century as inferred from high concentrations of Ti, Ca, and from magnetic susceptibility. This may coincide with higher wind intensities as suggested by higher proportions of epiphytic diatoms which point to an enhanced lateral transport from their littoral habitat towards the coring position at the center of the lake. In comparison with other records from southern Patagonia, the results from Laguna Las Vizcachas suggest opposite precipitation regimes between the western and eastern parts of Patagonia during that time which corresponds partly to the ‘Medieval Climate Anomaly’ chronozone. However, this proposal is compromised by the chronological uncertainties of the different records under consideration. The diatom record of Laguna Las Vizcachas indicates temperature changes: highest proportions of benthic diatoms point to coldest conditions from the mid-15th until the mid-17th century, followed by relatively warm conditions until the mid-18th century as suggested by a decrease of benthic taxa and a conspicuous rise of the planktonic/non-planktonic diatom ratio that can be used as an indicator for the length or presence/absence of winter ice cover. [Copyright &y& Elsevier]

The economic feasibility of Atriplex nummularia Lindl. and spineless cactus (Opuntia spp.) plantations for supplementing goats in the north-eastern plain of Mendoza (mean annual rainfall = 175 mm) during the fall–winter period was examined by a simulation model. It was run with 50–200 goats and annual rainfall probability (p;10–90% probability of occurrence). Cactus production was estimated from a rain-use efficiency factor of 12·5 kg DM ha−1 year−1 mm−1 and the annual rainfall probabilities in the area. Saltbush production (1·88 t DM ha−1year−1) was assumed not to be affected by annual rainfall thanks to the presence of a, 5–10 m deep, moderately saline water table (3·5–5·0 dSm−1). A decrease in goat mortality and an additional number of kids per goat were considered as annual benefits derived from supplementing the goat diet. The establishment cost (US$ ha−1) ranged from 812 (50 goats;p0·1 ) to 317 (200 goats; p0·9) for cacti plantations and from 691 (50 goats) to 378 (200 goats) for saltbush plantations, amounts that not all stockmen could afford. The cost of metallic fence installation was the main item of establishment cost for both shrubs. The nutrient costs for shrub production were lower than those for alfalfa hay, the conventional feed used by stockmen. A decrease in doe mortality from 10% to 2% and an increase in annual kid crop ranges from 0·17 to 0·32 would economically justify shrub plantations for stockmen having more than 50 goats at annual rainfall probabilities from p0·1 to p0·8. Limitations of the modelling effort and the feasibility of using the model in other areas of the world were stated. [Copyright &y& Elsevier]

The scientific community has made considerable efforts to improve the production of protein from traditional sources. Currently it has also been focused on non-conventional protein sources, such as those produced in conservation and sustainable use programs, which would contribute to the improvement of local and national economies. In Argentina, the meat of Caiman latirostris (the Broad-snouted caiman) is consumed; since commercial breeding of C. latirostris in the country has been incorporated relatively recently compared to other species of crocodiles and is growing, the qualities of the products that can be marketed have still been scarcely determined. Knowledge of caiman meat and its physical and chemical characteristics are necessary to promote its consumption. Thus, physical and chemical characteristics, including pH, cooking loss, color, tenderness, moisture, protein and fat content were determined in the meat of C. latirostris. Fifteen caimans (n = 15; X ± SD; 97.4 ± 1.2 cm of length and 4.2 ± 0.15 kg of weight) raised in captivity by Proyecto Yacaré (program for conservation and sustainable use of caiman) were slaughtered; meat samples were taken from the tail muscle Ischio-caudalis. Caiman meat was found to be luminous and tender, with a low amount of intramuscular fat (0.8%), usual proportion of protein in animal tissues (20.5%) and a high proportion of moisture (77.2%). Fatty acid content in caiman meat consisted of 30.2% of saturated fatty acids (SFA), 69.9% of unsaturated fatty acids (UFA), 36.8% of polyunsaturated fatty acids (PUFA), and 1.25 of PUFA/SFA ratio. Caiman meat (produced in management and conservation program in Argentina) might be marketed as a healthy meat given its very favorable lipid profile for human health, characterized by its low total lipid content, balanced fatty acids, tenderness and luminosity attributes, as well as characteristics similar to those of other usually marketed meats. The results may help to introduce an alternative source of protein and energy for human consumption, and to propose the meat of this caiman species as a healthy food. In addition, by involving local people, the activity improves the local economy and the economic return to the program, thereby supporting the conservation of this caiman species. • The meat of broad-snouted caiman presented a low amount of intramuscular fat and a high proportion of moisture and protein. • Lipid of this meat has a greater amount of PUFA, than others consumed meat, such as beef, chicken, pork, fish and sheep. • This meat is favorable to human health, it contains low SFA and high PUFA and good physico-chemical characteristics. • Caiman meat a is healthy product, of sustainable origin and whose commercialization collaborates with the conservation. [ABSTRACT FROM AUTHOR]