Characterization of novel Trichoderma spp. isolates as a search for effective biocontrollers of fungal diseases of economically important crops in Argentina
Consolo, Verónica Fabiana; Monaco, Cecilia Ines; Cordo, Cristina Alicia; Salerno, Graciela Lidia
Monoconidial cultures of 33 isolates of Trichoderma from Buenos Aires Province, Argentina were characterized on the basis of twenty eight morphological, physiological and biochemical features. All of them were screened for proteinase, endochitinase and â-1,3 glucanase activity. Universally primed PCR (UP-PCR) and inter-simple sequence repeat (ISSR) techniques were used to examine the genetic variability among isolates, which resulted in 127 bands for the total number of isolates. These results were subjected to numerical analysis revealing 20 haplotypes grouped in five clusters. The ability of Trichoderma isolates to antogonize soil-borne fungal plant pathogens using a dual culture assay was done against five fungal species: Alternaria sp., Bipolaris sorokiniana, Fusarium graminearum, F. solani, and Pyricularia oryzae. The highest inhibition values (85% RI) were obtained against B. sorokiniana and P. oryzae. Three isolates of T. harzianum named as FCCT2, FCCT3 and FCCT9 were capable of causing a high growth inhibition on four of the fungal species assayed, which was in agreement with their higher extracellular hydrolytic activity. Our results suggest that these isolates have the potential to be effective agents for biocontrol of cereal and tomato fungal pathogens.
Bioactive proteins from edible plants of Solanum genus.
Ordóñez, Roxana Mabel; Sayago, Jorge Esteban; Zampini, Iris Catiana; Rodriguez, Ivana Fabiola; Cattaneo, Florencia; Isla, Maria Ines
Bioactive proteins have been detected in manydifferent food sources. Beyond their nutritionalvalue many of them exhibit functional effects bothon the producing and on the consuming organisms.In recent years it has been recognized that proteinsprovide a rich source of biologically activepeptides. The genus Solanum has a great varietyof edible species that are an important source ofprotein. In this sense, some proteins might beinvolved in the response to wounding in plantdefense mechanisms like patatine and solamarineand snakin 1 and 2 isolated from S. tuberosumtubers and cyphomine isolated from S. betaceumfruits. They have shown in vitro inhibitory actionon hydrolases released by microorganisms involvedin cell wall degradation during the invasion process.They also have in vitro inhibitory effect onphytopathogenic microorganism growth for bothbacteria and fungi. It is thought that these proteinscould be part of the so-called pathogenesis-relatedproteins. As they are also present in edible tissue,these proteins have been studied from a functionalpoint of view. The purified proteins showedantioxidant or antiradical activities by a series ofin vitro tests, including DPPH, ABTS, hydroxyland superoxide radicals scavenging activityassays, anti-human low-density lipoproteinperoxidation tests, protections against hydroxylradical-mediated DNA damages, peroxynitritemediateddihydrorhodamine 123 oxidations andâ-carotene bleaching assay. A non mutagenic effectBioactive proteins from edible plants of Solanum genuswas observed in solamarine and cyphomine;solamarine also showed an antimutagenic effectagainst a direct mutagen. At present, an enzymatichydrolysis process on proteins is being carried outin order to obtain smaller molecules (peptides andfree amino acids) with improved nutritional qualityand safety. Three bioactive peptides (5A, 5C and6C) from potato protein hydrolysate fractions haverecently been isolated and showed antioxidantactivity. Hence, it would be possible to generatenew products and carry out alternative applicationsfor several agricultural and nutritional products.
Chemical Wear of Commercial Magnesia-Carbon Refractory Bricks in Air
Camerucci, Maria Andrea; Galliano, Pablo German; Cavalieri, Ana Lia; Tomba Martinez, Analia Gladys
In this work, the chemical degradation in air of different commercial MgO-C refractories used in the steelmaking industry was studied. Materials were characterized by mineralogical, microstructural, differential thermal and thermo-gravimetric analyses and measurements of density and porosity. Cylindrical samples were subjected to isothermal treatments at different temperatures and times in air and then, the weight loss and percentage of decarburized area were determined. Moreover, different surface conditionings (protective antioxidant paint and graphite powder muffle) were evaluated in regard to gas attack, and compared with non-conditioned specimens. The obtained results showed differences between the studied refractory materials according to the experimental conditions (temperature and time). At the low temperature regimen, pitch-based refractories exhibited the smallest chemical degradation whereas at high temperature, the material bonded with resin was the most resistant to oxygen chemical attack. The analysis of other phenomena related to microstructural changes helps to achieve a description of thermo-chemical processes occurring in the refractory samples during thermal treatments.
Siper-Virtual Reality Simulator of Periscope
Boroni, Gustavo Adolfo; Garcia Bauza, Cristian Dario; D'amato, Juan Pablo; Lazo, Marcos Gonzalo
In this paper an application designed to simulate the environment seen in a periscope by means of a virtual reality environment is presented. The application allows full viewing of all objects visible from the periscope, sea, ships, airplanes, etc. With the appropriate hardware (3D mouse and tracking systems) it is possible to navigate into the virtual world and interact with the elements. Each of the objects that appear in the navigation environment has been reproduced in the simulation model, including the behavior laws associated with it, so the complete functionality of the all objects can be simulated. This module is built into a larger and more complex computer system composed of the actual submarine simulator, with all its characteristic components (except the periscope) and the functional system, which simulates all the external signals that are captured by the submarine. The application automatically updates in the virtual environment any changes to the environment navigation and allows access, from this environment, to information on every component the same way as is done from a real periscope. The virtual reality application has been implemented in a hardware configuration and has the same interface as that used in the real periscope. In this way, the system developed can be integrated into a replica of the submarine emulating a real periscope, it being able to fully interact with the global system and allow totally real situations to be simulated.
La pedagogía de la investigación en la escuela secundaria y la implementación de Recorridos de Estudio e Investigación en matemática
Otero, Maria Rita; Llanos, Viviana Carolina; Gazzola Bascougnet, María Paz
En este trabajo se presentan resultados de una enseñanza por REI en la escuela secundaria, basada en la pedagogía de la investigación y del cuestionamiento del mundo, propuesta por Chevallard en la Teoría Antropológica de lo Didáctico (TAD). Se analizan protocolos para mostrar la actividad matemática del grupo de estudio. Se discuten algunos logros y se señalan ciertos obstáculos relativos a la implementación del REI y a la magnitud del cambio que es necesario realizar en la institución escuela secundaria.; In this paper some results related to teaching based on pedagogy of research and world questioning using Paths of Study and Research (PSR) at secondary school are presented. e framework of the Anthropological eory of Didactic (ATD) is used. Some protocols showing the mathematical activity of the study group are analyzed. Some achievements and obstacles related to the implementation of Paths of Study and Research (PSR) at secondary school are discussed, also, the challenges of the necessary changes in the secondary school are considered.
El diario Clarín y la "campaña antiargentina": la construcción de un consenso en torno a las violaciones a los derechos humanos
Iturralde, Micaela
Este artigo propõe uma indagação acerca do tratamento informativo e da linha editorial realizada pelo jornal diário argentino Clarín, sobre violações de direitos humanos cometidas na Argentina durante o regime militar 1976-1983. O texto está centrado na análise da conjuntura que começa em 1977 e continua em 1978, quando os militares iniciam uma campanha pública dizendo que há uma “campanha anti-argentina” e que as queixas de organismos internacionais pelo quadro dentro da Argentina eram, na realidade, interpretadas como parte da “ameaça subversiva” que se operava desde o interior do país, assim como do próprio exterior. Considerando que a omissão informativa que caracteriza a denúncia de uma “campanha anti-argentina” se refere diretamente à questão da repressão militar, consideramos também que as construções discursivas e representações criadas e difundidas por Clarín neste contexto - caracterizadas por uma adesão total à chamada “luta anti-subversiva” e pela exaltação nacionalista e patriótica (e êxito) em torno da Copa do Mundo de Futebol de 1978 -, constituíram o modo com que o jornal abordou o tema das violações dos direitos humanos.; En este artículo nos proponemos indagar el tratamiento informativo y editorial otorgado por el diario Clarín a las violaciones a los derechos humanos cometidas en la Argentina por el régimen militar que gobernó entre 1976 y 1983. Nos abocaremos al análisis de la coyuntura que se abre en 1977 y se extiende durante todo 1978, cuando se vuelve recurrente en las intervenciones públicas de los militares la denuncia de una supuesta “campaña antiargentina”, en la que los reclamos internacionales por la situación nacional fueron interpretados como parte de la “amenaza subversiva” que operaba desde el interior y el exterior. Dado que la omisión informativa que caracteriza la denuncia de una “campaña antiargentina” refiere directamente a la cuestión de la represión estatal, consideramos que las construcciones discursivas y representaciones creadas y difundidas por Clarín en este contexto, caracterizadas por una adhesión total a la llamada “lucha antisubversiva” y por la exaltación nacionalista y patriótica y el exitismo en torno al Mundial de Fútbol, constituyeron el modo en que el diario abordó el tema de las violaciones a los derechos humanos.
The relationship of clinical, cognitive and social measures in schizophrenia: A preliminary finding combining measures in probands and relatives
Huepe, David; Riveros, Rodrigo; Manes, Facundo Francisco; Couto, Juan Blas Marcos; Hurtado, Esteban; Cetkovich Bakmas, Marcelo Gustavo; Escobar, Maria; Vergara, Viviana; Parrao, Teresa; Ibanez Barassi, Agustin Mariano
This study examines performance of schizophrenia patients, unaffected relatives and controls in social cognition, cognitive and psychiatric scales looking for possible markers of vulnerability in schizophrenia. Performance of schizophrenia patients from multiplex families, first-degree relatives, and matched controls was compared and, subsequently, discriminant analysis method was used for identifying the best predictors for group membership. By using Multigroup Discriminant Analyses on the three groups, the best predictors were PANSS, Premorbid Adjustment Scale, Faux Pas test, and a face/emotion categorizing task. This model obtained 82% correct global classification, suggesting that the combination of psychiatric scales and neuropsychological/ social cognition tesks are the best approach for characterizing this disease. Although preliminary, our results suggest that social cognition tasks are robust markers of schizophrenia family impairments, and that combining clinical, social and neuropsychological measures is the best approach to asses patients and relatives vulnerability.
The role of vision in auditory distance perception
Calcagno, Esteban; Abregú, Ezequiel Lucas; Eguia, Manuel Camilo; Vergara, Ramiro Oscar
In humans, multisensory interaction is an important strategy for improving the detection of stimuli of different nature and reducing the variability of response. It is known that the presence of visual information affects the auditory perception in the horizontal plane (azimuth), but there are few researches that study the influence of vision in the auditory distance perception. In general, the data obtained from these studies are contradictory and do not completely define the way in which visual cues affect the apparent distance of a sound source. Here psychophysical experiments on auditory distance perception in humans are performed, including and excluding visual cues. The results show that the apparent distance from the source is affected by the presence of visual information and that subjects can store in their memory a representation of the environ- ment that later improves the perception of distance.
Abundance and diversity of tintinnids (planktonic ciliates) under contrasting levels of productivity in the Argentine Shelf and Drake Passage
Santoferrara, Luciana Fernanda; Alder, Viviana Andrea
The relationship between the abundance and diversity of tintinnids and the concentration of chlorophyll a (Chla) was contrasted between neritic and oceanic waters of the SW Atlantic during autumn and summer. Chla and tintinnid abundance and biomass reached maximum values (17.53μgL -1, 2.76×10 3ind.L -1, and 6.29μgCL -1, respectively) in shelf waters during summer, and their mean values generally differed by one order of magnitude between environments. Peaks in species richness (13) and Shannon diversity index (2.12) were found in the shelf-ocean boundary, but both variables showed nonsignificant differences between areas. Species richness correlated significantly with both Chla and abundance. Such relationships, which followed a negative linear or quadratic function in the shelf and a positive linear function in oceanic waters, are thought to reflect either the competitive dominance of one species or a relatively wide spectrum of tintinnid size-classes, respectively.
Dolor crónico, legitimidad y clausura: experiencias y saberes sobre la migraña
del Mónaco, Romina Laura
Este artículo analiza, desde una perspectiva socio-antropológica, las percepciones y experiencias de personas con un tipo de dolor de cabeza crónico, que los profesionales de la salud y los pacientes denominan migraña. El trabajo de campo se llevó a cabo en un hospital público de la Ciudad de Buenos Aires, donde se realizaron entrevistas a médicos neurólogos y personas con esta dolencia. Combinando la perspectiva fenomenológica con el interaccionismo simbólico propongo indagar cómo la percepción y las experiencias con el dolor influyen en la constitución de sí mismo, de la corporalidad y de las interacciones con los otros. Asimismo, se observan algunas particularidades de la migraña que la diferencian de otras dolencias crónicas y que condicionan los modos en que los pacientes se relacionan con su entorno. En primer lugar, carece de condiciones fácticas de verificación y no tiene una etiología precisa ni un tratamiento eficaz. En segundo lugar, se tiende a vincular esta dolencia con excusas, mentiras y manipulación. A partir de esto surgen cuestiones que vinculan el padecimiento con falta de legitimidad, angustia, aperturas y clausuras del yo que influyen en las relaciones de quienes padecen consigo mismos y con los otros.
Evaluación del desempeño de modelos de dispersión de contaminantes aplicados a cañones urbanos; Evaluation of the performance of atmospheric dispersion models applied to urban street canyons
Venegas, Laura Esperanza; Mazzeo, Nicolas Antonio
En los cañones urbanos, frecuentemente, se presentan concentraciones de contaminantes en aire varias veces superiores a la contaminación de fondo urbana. En este trabajo, se comparan valores de concentraciones de monóxido de carbono (CO) en aire medidas dentro de un cañón urbano con las estimadas mediante algunos modelos de dispersión atmosférica aplicables a procesos que se verifican en los cañones: STREET, STREET-BOX, OSPM y AEOLIUS. Se presenta la evaluación para condiciones de sotavento, barlovento y para direcciones intermedias del viento. En la comparación, se utilizaron los valores horarios de concentraciones de CO en aire medidas durante un año en el interior de un cañón urbano de Göttinger Strässe (Hannover, Alemania) y en el techo de un edificio lindero, de velocidad y dirección del viento observadas en el techo del mismo edificio y de flujo de tránsito vehicular en la calle del cañón. Para evaluar cuantitativamente el desempeño de los modelos, se calcularon los valores medios observados y estimados, el desvío, el error cuadrático medio y el error fraccional para las direcciones de viento correspondientes a sotavento, barlovento e intermedias. Los resultados generados por el modelo STREET con una constante empírica k=7 (valor del modelo original), subestimaron las concentraciones observadas, obteniéndose un mejor desempeño con k= 12,1. El modelo STREET-BOX es adecuado para condiciones de sotavento y direcciones intermedias, pero presenta diferencias importantes con las concentraciones observadas a barlovento. En general, los resultados aportados por los modelos OSPM y AEOLIUS fueron los que menos se apartaron de los valores observados.; Air pollutant concentrations inside street canyons are usually several times background concentrations in urban areas. In this paper, carbon monoxide (CO) concentrations observed in a street canyon are compared with estimated values obtained using four atmospheric dispersion models: STREET, STREET-BOX, OSPM and AEOLIUS. Results for leeward, windward and intermediate wind directions are analyzed. Data used in the model evaluation include one year of hourly CO concentrations measured inside a street canyon of Göttinger Strässe (Hannover, Germany) and at the roof of a nearby building, wind speed and direction data registered at the roof of the nearby building and traffic flow in the street. Each model performance was evaluated for leeward, windward and intermediate wind directions. Results obtained with the STREET model considering the empirical constant k=7 (default value), underestimated observed concentrations. A better performance of the STREET model was obtained with k= 12.1. The STREET-BOX model gave acceptable results for leeward and intermediate wind directions. The results of this model showed great differences with observed windward concentration values. In general, the concentrations estimated by OSPM and AEOLIUS showed the best agreement with observed values.
An analysis of 332 fatalities infected with pandemic 2009 influenza A (H1N1) in Argentina.
Balanzat, Ana M.; Hertlein, Christian; Apezteguia, Carlos; Bonvehi, Pablo; Cámera, Luis; Gentile, Angela; Rizzo, Oscar; Gómez Carrillo, Manuel; Coronado, Fatima; Azziz Baumgartner, Eduardo; Chávez, Pollyanna R.; Widdowson, Marc Alain
Background: The apparent high number of deaths in Argentina during the 2009 pandemic led to concern that the influenza A H1N1pdm disease was different there. We report the characteristics and risk factors for influenza A H1N1pdm fatalities. Methods: We identified laboratory-confirmed influenza A H1N1pdm fatalities occurring during June-July 2009. Physicians abstracted data on age, sex, time of onset of illness, medical history, clinical presentation at admission, laboratory, treatment, and outcomes using standardize questionnaires. We explored the characteristics of fatalities according to their age and risk group. Results: Of 332 influenza A H1N1pdm fatalities, 226 (68%) were among persons aged <50 years. Acute respiratory failure was the leading cause of death. Of all cases, 249 (75%) had at least one comorbidity as defined by Advisory Committee on Immunization Practices. Obesity was reported in 32% with data and chronic pulmonary disease in 28%. Among the 40 deaths in children aged <5 years, chronic pulmonary disease (42%) and neonatal pathologies (35%) were the most common co-morbidities. Twenty (6%) fatalities were among pregnant or postpartum women of which only 47% had diagnosed co-morbidities. Only 13% of patients received antiviral treatment within 48 hours of symptom onset. None of children aged <5 years or the pregnant women received antivirals within 48 h of symptom onset. As the pandemic progressed, the time from symptom-onset to medical care and to antiviral treatment decreased significantly among case-patients who subsequently died (p<0.001). Conclusion: Persons with co-morbidities, pregnant and who received antivirals late were over-represented among influenza A H1N1pdm deaths in Argentina, though timeliness of antiviral treatment improved during the pandemic.
Anomalous magnetization enhancement and frustration in the internal magnetic order on (Fe0.69Co0.31)B0.4 nanoparticles
Molina Concha, Belén; Zysler, Roberto Daniel; Romero, Héctor
We have studied the internal magnetic order of 3-nm (Fe0.69Co0.31)0.6B0.4 amorphous nanoparticles. These nanoparticles were dispersed in a non-magnetic matrix (non-interacting nanoparticles) to contrast them with the powder samples, where strong interparticle interactions are present. In similar fashion to the bulk alloy, this system exhibits a saturation magnetization maximum as a function of Fe composition near 69 at% Fe for the powder and dispersed samples at all temperatures. The saturation magnetization (MS) of the dispersed sample shows anomalous behavior, revealing frustration in the internal magnetic order of the particles. Unexpectedly, the MS of the non-interacting sample at low temperatures is larger than the corresponding bulk alloy or the calculated value of MS for the same Fe-Co composition. By contrast, the powder sample has low MS values and it is approximately constant in temperature.
Influence of network dynamics on the spread of sexually transmitted diseases
Risau Gusman, Sebastian Luis
Network epidemiology often assumes that the relationships defining the social network of a population are static. The dynamics of relationships is only taken indirectly into account by assuming that the relevant information to study epidemic spread is encoded in the network obtained, by considering numbers of partners accumulated over periods of timeroughly proportional to the infectious period of the disease. On the other hand, models explicitly including social dynamics are often too schematic to provide a reasonable representation of a real population, or so detailed that no general conclusions can be drawn from them. Here, wepresent a model of social dynamics that is general enough so its parameters can be obtained by fitting data from surveys about sexual behaviour, but that can still be studied analytically, using mean-field techniques. This allows us to obtain some general results about epidemic spreading. We show that using accumulated network data to estimate the static epidemic threshold lead to a significant underestimation of that threshold. We also show that, for a dynamic network, the relative epidemic threshold is an increasing function of the infectious period of the disease, implying that the static value is a lower bound to the real threshold. A practical example is given of how to apply the model to the study of a real population.
Physicochemical and structural properties of amaranth protein isolates treated with high pressure
Condes, María Cecilia; Speroni Aguirre, Francisco José; Mauri, Adriana Noemi; Añon, Maria Cristina
The effects of high pressure (HP) (200, 400 and 600 MPa) on physicochemical and structural properties of amaranth proteins treated at different protein concentrations (1, 5 and 10% w/v) were studied. HP provoked denaturation of amaranth proteins which were very sensitive to HP treatment, achieving almost complete denaturation (93%) at 400 MPa. After HP, the resistant structures from glutenins, globulin-11S and globulin-P exhibited an increased thermal stability while those from albumins and globulin-7S exhibited a decrease of thermal stability. Increasing intensities of HP treatments provoked the disappearance of electrophoretic bands with molecular mass higher than 45 kDa, together with changes in the polypeptides fractions of low molecular weight. HP treatments induced the formation of insoluble aggregates and the dissociation of soluble aggregates. Protein concentration modulated the effects of HP on amaranth proteins. These modified proteins could present improved functional properties.
Galaxy triplets in Sloan Digital Sky Survey Data Release 7 - I. Catalogue
O'Mill, Ana Laura; Duplancic Videla, Maria Fernanda; Garcia Lambas, Diego Rodolfo; Valotto, Carlos Alberto; Sodré Laerte, Jr
We present a new catalogue of galaxy triplets derived from the Sloan Digital Sky Survey Data Release 7. The identification of systems was performed considering galaxies brighter than M_r=-20.5 and imposing constraints over the projected distances, radial velocity differences of neighbouring galaxies and isolation. To improve the identification of triplets we employed a data pixelization scheme, which allows to handle large amounts of data as in the SDSS photometric survey. Using spectroscopic and photometric data in the redshift range 0.01
Microbivalves from the Monte Leon Formation (Early Miocene), Patagonia, Argentina
Griffin, Miguel; Pastorino, Roberto Santiago Guido
Three new species (Mysella donaciformis n. sp., Cosa helianthea n. sp., and Lissarca saraballentae n. sp.) of small bivalves are described from early Miocene rocks in southern Patagonia. The outcrops lie along the coast of the province of Santa Cruz, within the boundaries of the Monte León National Park. The fossil-rich rocks exposed there at the base of the coastal cliff are included in the Punta Entrada Member of the Monte León Formation. This stratigraphic unit has been dated as early Miocene. It was probably deposited in a tidally-influenced near-shore and fully marine environment. The affinities of these small mollusks lie with taxa known to occur in other areas of the Southern Ocean, such as Antarctica, Australia, and New Zealand. The dispersal of these mollusks across vast expanses of water by means of rafting on drifting kelp is discussed.
Invasive non-native species of fish in Upper Paraná river Basin, Brazil: variations of caloric content in Cichla kelberi
Espinola, Luis Guillermo; Júlio Junior, H. F; Benedito, E
The allocation of assimilated energy may be influenced by seasonal changes, growth, and reproductive cycle of fish, food consumption and environmental conditions. The objective of this research was to evaluate the energetic variations of Cichla kelberi in the upper Paraná River floodplain, analyzing the caloric content in muscles, gonadosomatic index (GSI), and the condition factor between assessed systems, sex, and stage of gonadal maturation. The results obtained in the present study permit assuring that this is a species that efficiently converts the resources of the environment into energy. Although presenting higher condition factor in the environment where there is a greater ease in getting food (Paraná subsystem), the energy identified in the muscles was the same in both subsystems. During the process of gonadal maturation there is optimization in energy accumulation in the muscles of females, before and after reproductive period, and somatic growth occurs significantly when the individual is not reproducing. Further detailed studies on ecological mechanisms influencing the success of the species, as the presence of competitors and preference for native preys, are needed to implement effective management measures aimed at preventing that the species proliferation in the environment is even more damaging to local biodiversity.
Electrocatalysis: Fundamentals and Applications
Zinola, Carlos F.; Martins, María Elisa; Pastor Tejera, E.; Pimenta Neves, Newton
Electrocatalysis is a special field in Electrochemistry that hasgained a special growth after the late eighties due to theapplication of new hybrid techniques. However, most of theapplications have run for academic purposes but not fortechnical uses in the industry. Nowadays, the application ofnew concepts of electrocatalysis for industrial electrochemi-cal processes has appeared as a necessity and not only attract-ing attention for chemists but for engineers. Therefore,industrial electrocatalytic processes have only been presentedin the literature from the chemical engineering point of viewwith few further electrochemical explanations and mainlyduring the late seventies. The design and preparation of anelectrocatalyst (electrodes for technological uses) are basedon new concepts such as a controlled surface roughness,atomic topographic profiles, defined catalytic centre sites,atomic rearrangements, and phase transitions in the courseof the electrochemical reactions.
Importancia del autoabastecimiento energético: Impactos directos e indirectos sobre el crecimiento
Recalde, Marina Yesica
Este trabajo presenta un abordaje teórico de las implicancias directas, dados los límites biofísicos de la economía, e indirectas, por intermedio del impacto en la balanza comercial, de la falta de abastecimiento local. Como caso de estudio se analiza la situación actual del sistema energético argentino, y la existencia de ambas limitaciones a raíz de la caída del grado de autoabastecimiento energético y las crecientes demandas de importación de recursos energéticos. Los resultados del análisis muestran que la falta de abastecimiento local requerirá de importaciones crecientes de energía para sustentar el crecimiento económico, particularmente en el caso de países en desarrollo como Argentina. Esta situación ejerce una presión sobre la balanza de pagos, tal como lo predice la Ley de Thirwall, aún más importante atendiendo a la estructura de las importaciones y exportaciones locales. Se desprende de las conclusiones la importancia de la política energética tendiente al autoabastecimiento nacional.