CONICET Digital

Electromagnetic Signatures of Possible Charge Anomalies in Tunneling

Electromagnetic Signatures of Possible Charge Anomalies in Tunneling Minotti, Fernando Oscar; Modanese, Giovanni We reconsider some well-known tunneling processes from the point of view of Aharonov-Bohm electrodynamics, a unique extension of Maxwell’s theory which admits charge-current sources that are not locally conserved. In particular we are interested into tunneling phenomena having relatively long range (otherwise the non-Maxwellian effects become irrelevant, especially at high frequency) and involving macroscopic wavefunctions and coherent matter, for which it makes sense to evaluate the classical e.m. field generated by the tunneling particles. For some condensed-matter systems, admitting discontinuities in the probability current is a possible way of formulating phenomenological models. In such cases, the Aharonov-Bohm theory offers a logically consistent approach and allows to derive observable consequences. Typical e.m. signatures of the failure of local conservation are at high frequency the generation of a longitudinal electric radiation field, and at low frequency a small effect of “missing” magnetic field. Possible causes of this failure are instant tunneling and phase slips in superconductors. For macroscopic quantum systems in which the phase-number uncertainty relation (Formula presented.) applies, the expectation value of the anomalous source (Formula presented.) has quantum fluctuations, thus becoming a random source of weak non-Maxwellian fields.

Calibrating APSIM for forage sorghum using remote sensing and field data under sub-optimal growth conditions

Calibrating APSIM for forage sorghum using remote sensing and field data under sub-optimal growth conditions Della Nave, Facundo Nicolás; Ojeda, Jonathan J.; Irisarri, Jorge Gonzalo Nicolás; Pembleton, Keith; Oyarzabal, Mariano; Oesterheld, Martin CONTEXT: Mechanistic sorghum models have been mostly used to estimate sorghum yield for grain sorghum for a range of genotype, management, and environmental conditions. There is a lack of model testing for crop growth and development responses for forage genotypes and information for phenological parameterization under sub-optimal water and nitrogen stress conditions in forage systems. OBJETIVE: The aims of this study were to (i) use NDVI to parametrize APSIM model to estimate forage sorghum phenology, (ii) calibrate APSIM to simulate green cover, intercepted solar radiation and aboveground biomass, and (iii) quantify the variance of inter-annual aboveground biomass and the effect of water availability on forage sorghum biomass under sub-optimal environment × management combinations. METHODS: We used climate, soil, management records and sorghum crop observations collected from farm and field experiments in Argentina and Australia. NDVI values were gathered from Sentinel-2 and a handheld optical sensor and then related to fAPAR measurements. Phenological stages were derived from fAPAR seasonal dynamics and implemented as input in the APSIM calibration. Finally, we assessed the temporal AGB variability through long-term simulations analysis. RESULTS AND CONCLUSIONS: NDVI seasonal dynamics accurately represented the fraction of the absorbed photosynthetically active radiation (R2=0.92) and then, the remote-sensing parametrized APSIM model satisfactorily simulated crop phenology (CCC=0.75-0.92, NRMSE=9-22%). The model was also able to satisfactorily simulate crop growth (CCC=0.89 and NRMSE=24.8% for green cover; CCC=0.81 and NRMSE=34.6% for intercepted solar radiation; CCC=0.91 and NRMSE=37% for aboveground biomass). APSIM simulations during 22 years across 5 contrasting locations showed high inter-annual variability of aboveground biomass (CV=47%), mainly driven by inter-annual variation of soil water availability (CV=20%). Our study demonstrated that (i) remote sensing data was a reliable source for APSIM phenology parametrization, (ii) the model was able to satisfactorily simulate crop growth and development of forage sorghum under sub-optimal conditions across several genotype × environment × management combinations and (iii) water availability was the main driver of aboveground biomass inter-annual variance. SIGNIFICANCE: Given the pressure of the global human population to satisfy an increasing demand for food, our results provide a new path for the combined use of remote sensing and mechanistic modelling to improve forage sorghum biomass estimations in marginal environments.

Genetic Structure of a Native Neotropical Fish Species: New Insights about a South American Bioindicator

Genetic Structure of a Native Neotropical Fish Species: New Insights about a South American Bioindicator Rautenberg, Gisela Evelín; Bonifacio, Alejo Fabian; Chiappero, Marina Beatriz; Amé, María Valeria; Hued, Andrea Cecilia The biodiversity of Neotropical region is affected by anthropogenic disturbance. Throughout Brazil, Argentina and Uruguay, the native fish, Cnesterodon decemmaculatus, is well distributed and widely used as an excellent bioindicator of environmental quality. We investigated the diversity and genetic structure of its populations along a water pollution gradient to answer the following questions: 1- Does the genetic diversity decrease under the stressful conditions of a severe water quality gradient? and 2- Is there any relationship between the haplotypes registered along the studied basin and those recorded in other distant basins? Two mitochondrial DNA markers, Cytochrome b and D-loop, were analyzed and four haplotypes were registered for both markers along the basin. H1 was present throughout all the river sections in high frequencies leading to a low genetic diversity. We suggest that only a few haplotypes tolerate the stressful conditions of mountain rivers. On the other hand, the presence of H4 at the site located downstream suggests a history of recent colonization from the southeast to the northwest of the biome. These results, together with the abundance decrease along the pollution gradient, and the non-migratory characteristic of C. decemmaculatus suggest that its populations may be at risk of local extinction.

Analysis of vaccination strategy against cystic echinococcosis developed in the Province of Río Negro, Argentina: 12 years of work

Analysis of vaccination strategy against cystic echinococcosis developed in the Province of Río Negro, Argentina: 12 years of work Labanchi, Jose Luis; Poggio, Thelma Veronica; Gutiérrez, Ariana; Mujica, Guillermo Bernardo; Araya, Daniel; Grizmado, Claudia; Calabro, Arnoldo; Crowley, Pablo Ernesto; Arezo, Marcos; Seleiman, Marcos; Herrero, Eduardo; Sepulveda, Luis; Talmon, Gabriel; Diaz, Oscar; Larrieu, Edmundo Juan Cystic echinococcosis (CE) is a zoonosis caused by species of the complex Echinococcus granulosus, sensu lato in their larval stage. It is an endemic disease in the province of Río Negro, where small farmers generally have both sheep and goats. Lamb vaccination with EG95 was incorporated in 2009 with very good results: in fact, it contributed to a significant drop in prevalence of infection in both sheep and goats, when determined by necropsy and serology in 2018. In the design of the activity, it was decided not to vaccinate goats in order to minimize the operational requirements of vaccination and comments from producers about the rarity of observing hydatid cysts in goat viscera were considered. Objective: To identify causes which can still generate infection in dogs, and to detect species/genotypes in circulation in the province of Río Negro. Materials and methods: In indigenous reserves comprised within the area of lamb vaccination with 3 doses of EG95, (dose 1 in December, dose 2 in January and dose 3 in December of the year following, at the time of application of dose 1 to the new lambs). Prevalence in adult goats and sheep was determined by necropsy and serology (ELISA). Infective species/genotypes present in the work area and in the rest of the province of Río Negro were identified by Cox1 mitochondrial gene sequencing. Epidemiological analysis was completed with surveys among farmers about slaughter habits for human consumption. Results: Through serology and necropsy, infection rates in vaccinated and nonvaccinated sheep were significantly different (21% versus 66%). Non-vaccinated sheep and non-vaccinated goats were also significantly different in that there was less infection in goats compared to sheep (7% versus 66% for necropsy, 30% versus 61% for serology); After many years of sheep vaccination the infection positives were low, and differences between vaccinated sheep and non-vaccinated goats turned out non-significant (21% versus 7%). With reference to epidemiology and control along the period 2018–2022, PZQ dosing of dogs 4 times a year was maintained, and 2 extra deworming tasks were introduced together with dose 1 and 2 of EG95, performed by the veterinary vaccination team, ensuring the ingestion of PZQ by dogs. Assessment of animal slaughter for consumption in 41 producers showed that 21 of them slaughter a monthly average of 18 goats (an average of 0.43 goat per month per farm) and 36 in all slaughter 35 old sheep in a year (average of 0.85 sheep per month per farm). With respect to identification of species/genotypes as from 2010, genotypes G1 have been found in 11 sheep (out of which 6 belong to vaccination zone) and genotypes G7, in one pig. A goat cyst within vaccination zone turned out unfertile and it was not possible to sequence it. Conclusion: Design and implementation of a vaccine programme combined with the use of PZQ resulted as cost-effective, since it was possible to maintain the vaccine over time, with clear impact on prevalence decrease in sheep and goats.

Rebellion of the Girls: Traces of Feminist Memory in Argentina

Rebellion of the Girls: Traces of Feminist Memory in Argentina Lenguita, Paula Andrea Following the people s outcry of the Not One Less movement in Argentina the question has arisen of how to construct a history of Argentine feminism that contains the antecedents of this manifestation In this sense this paper has adopted a combination of theoretical approaches to the militant heritage of the political movement in the last half century re-establishing the contributions of the Argentine Feminist Union 1970-1976 and the National Encounters of Women 1986-2019 The hypothesis is that in these legacies lie the organisational keys to the women s movement and the antecedents of the so-called Rebellion of the Girls in the Not One Less movement This is a brand new political phenomenon for national feminism which has had international repercussions due to its narrative power through social networks Different testimonies of leading participants have been considered with the aim of contributing to a remembrance of the deliberative and narrative modes of the recent feminist experience in Argentina associated with horizontal participation and heterogeneity in ideological positions providing people support for the political scope of these manifestations.

Hybrid Meat Products: Incorporation of White Bean Flour in Lean Pork Burgers

Hybrid Meat Products: Incorporation of White Bean Flour in Lean Pork Burgers Argel, Natalia Soledad; Lorenzo, Gabriel; Domínguez, Rubén; Fraqueza, Maria João; Fernández López, Juana; Sosa, Maria Elena; Campagnol, Paulo Cesar Bastianello; Lorenzo, José Manuel; Andres, Silvina Cecilia The effect of partial lean pork-meat replacement by white Phaseolus vulgaris L. flour in hybrid burgers was studied. A multivariate regression model was used to test different bean flour levels (BF: 8–15 g/100 g) and water/bean flour ratios (W/BF: 1.2, 1.6, and 1.8 g/g). Process yield, texture profile analysis, color parameters, thermal transitions, and microstructure of the systems were analyzed. Respond Surface Methodology was used to model the response behaviors and optimization. Burgers with BF showed yields higher than 88%. Hardness and cohesiveness decreased as the BF level increased, with a more noticeable effect when the W/BF ratio became larger. Regarding color, the higher the BF and the W/BF ratio in burgers, the higher the L* obtained. The desirability optimization predicted an optimum formulation consisting of 15 g BF/100 g and 1.36 g/g W/BF with similar attributes to a commercial pork burger. The thermal analysis showed an increase in the enthalpy associated with the myosin denaturation and the interactions between meat proteins and BF led to higher temperatures for the starch gelatinization and protein denaturation. The microstructure of BF burgers presented a more stable coarse gel matrix derived from coagulated meat proteins combined with the flour components. The mathematical procedure adequately predicted the hybrid burger quality attributes.

The need for coordination to develop customized competitiveness in agrifood systems: lemon, pork, and dairy in Argentina

The need for coordination to develop customized competitiveness in agrifood systems: lemon, pork, and dairy in Argentina Gonzalez, Andrea Lorena; Hallak, Juan Carlos; Scattolo, Gabriel; Tacsir, Andrés Purpose: The purpose of this research is to analyze the ability of agrifood systems to construct “customized competitiveness” strategies that can allow firms to meet the specific and constantly changing demands of foreign markets. Design/methodology/approach: The research performs a comparative analysis of three case studies of agrifood systems in Argentina: lemon, pork, and dairy products. The authors obtained primary data from 79 semi-structured interviews with key persons in each agrifood system carried out online between March 2020 and February 2021. Secondary data was obtained from databases, academic studies, and reports from business associations and public agencies. Findings: The authors find wide disparities in the development of customized competitiveness strategies between the studied agrifood systems (higher in lemon, lower in dairy products, and incipient in pork). The authors attribute the disparity to the varying degrees in which these systems are capable of coordinating their own actions and their interactions with State agencies. Originality/value: The paper provides comparative evidence about the role of private coordination in the ability of agrifood systems to construct customized competitiveness strategies.

La construcción de capacidades en las industrias basadas en recursos naturales: la bioenergía en Argentina

La construcción de capacidades en las industrias basadas en recursos naturales: la bioenergía en Argentina; Building capabilities in natural resource-based industries: the bioenergy in Argentina Castelao Caruana, Maria Eugenia; de Vita, Mariel Soledad Las tendencias globales en materia de seguridad energética y mitigación del cambio climático representan un espacio de oportunidad para que los países de América Latina y el Caribe, especializados en la producción de recursos naturales, desarrollen nuevas ventajas competitivas y actividades de mayor valor agregado. El artículo identifica y analiza las capacidades productivas y tecnológicas que construyen las firmas que ingresan en la industria de la bioenergía con fines térmicos o eléctricos en Argentina, y las redes de colaboración que integran y facilitan el aprendizaje dentro y fuera de esta industria. El trabajo aplica un estudio de caso múltiple conformado por empresas ubicadas en las provincias de Santa Fe y Buenos Aires (Argentina) con diferentes trayectorias tecnológicas. La evidencia corrobora que las capacidades que adquieren las firmas están condicionadas por su trayectoria, pero también muestra que la interacción con entidades portadoras de otras bases de conocimiento facilita la creación de nuevo conocimiento en torno a la especificidad de los recursos naturales.; Global trends in energy security and climate change mitigation represent a space of opportunity for the countries of Latin America and the Caribbean, specialized in the production of natural resources, to develop new competitive advantages and higher value-added activities. The article identifies and analyzes the productive and technological capabilities built by firms when entering the bioenergy industry for thermal or electrical purposes in Argentina, and the collaboration networks that integrate and facilitate learning inside and outside this industry. The work applies a multiple case study composed by firms located in the provinces of Santa Fe and Buenos Aires (Argentina) with different technological trajectories. The evidence corroborates that the capacities that firms acquire are conditioned by their trajectory, but it also shows that the interaction with entities that carry other knowledge bases facilitates the creation of new knowledge around the specificity of natural resources.

Ocupaciones de cazadores-recolectores en el Campo de Dunas del Centro Pampeano durante el Holoceno tardío. El caso de la localidad arqueológica Laguna Giaccone (Buenos Aires, Argentina)

Ocupaciones de cazadores-recolectores en el Campo de Dunas del Centro Pampeano durante el Holoceno tardío. El caso de la localidad arqueológica Laguna Giaccone (Buenos Aires, Argentina); Hunter-gatherer occupations in the Central Pampean Dunefields during the late holocene: the laguna Giaccone archaeological locality as a case study (Buenos Aires, Argentina) Alvarez, María Clara; Santos Valero, María Florencia; Borges Vaz, Erika; Messineo, Pablo Geronimo Se presentan los primeros resultados de las investigaciones efectuadas en la localidad arqueológica Laguna Giaccone, ubicada en el Campo de Dunas del Centro Pampeano (Buenos Aires, Argentina). Los objetivos son evaluar los aspectos tafonómicos que afectaron el conjunto óseo y determinar las especies animales explotadas, identificar las materias primas líticas, las áreas de procedencia y las tendencias tecnológicas desarrolladas y analizar los aspectos tecno-morfológicos relacionados con la manufactura de la cerámica. Entre los procesos y agentes que más afectaron al conjunto faunístico se encuentran el manganeso, los roedores, el pisoteo y la acción de insectos. Se evidencia que el guanaco, el ñandú y un cormorán/biguá fueron procesados por los grupos cazadores-recolectores. Respecto al material lítico, predominan la ortocuarcita y la ftanita de las Sierras de Tandilia y se identificó una amplia diversidad de rocas procedentes de otras fuentes de la región pampeana. Están presentes las últimas etapas de las cadenas operativas y una amplia diversidad de instrumentos. Se registró un alto número de vasijas, algunas confeccionadas mediante la técnica de rollo y cocinadas bajo una atmosfera no oxidante. Las morfologías corresponden a contenedores abiertos y algunos tiestos están decorados. Las distintas líneas de evidencia sugieren que parte de las ocupaciones corresponderían a loci de actividades múltiples desarrolladas durante el Holoceno tardío donde se habrían efectuado diversas tareas vinculadas con el ámbito doméstico, como el procesamiento y consumo de los recursos animales, la manufactura y uso de instrumentos líticos y la preparación de los alimentos en los recipientes cerámicos.; We present the first results of the investigations carried out at the Laguna Giaccone archaeological locality, situated in the Central Pampean Dunefields (Buenos Aires, Argentina). The objectives are to evaluate the taphonomic processes that affected the bone assemblage and to determine the animal species exploited, to identify the lithic raw materials, their acquisition areas, and the technological trends developed, and to analyze the techno-morphological characteristics related to the manufacture of pottery. Among the processes and agents that most affected the faunal assemblage are manganese, rodents, trampling, and the action of insects. The guanaco, the greater Rhea and a cormorant were processed by the hunter-gatherer groups. Regarding the lithic material, orthoquartzite and chert from the Tandilia Hills are predominant and a wide diversity of rocks from other sources of the Pampas region were recorded. The last stages of the chaîne opérotoire and a wide variety of tools were identified. A high number of vessels was recorded, some made using the roll technique and cooked under a non-oxidizing atmosphere. The morphologies correspond to open containers and some potsherds are decorated. The different lines of evidence suggest that part of the occupations correspond to loci of multiple activities camps developed during the Late Holocene, where various tasks related to the domestic sphere were carried out, such as the processing and consumption of animal resources, the manufacture and use of lithic tools, and the preparation of food in ceramic containers.

Humedales en acción: Su función en la remoción de contaminantes

Humedales en acción: Su función en la remoción de contaminantes Primost, Jezabel Elena; Peluso, María Leticia; Sasal, María Carolina; Bonetto, Carlos Alberto Los humedales están siendo cada vez más reconocidos tanto por sus características particulares como por sus funciones ecosistémicas. Sin embargo, en las últimas décadas, la extensión de humedales naturales viene disminuyendo en todo el mundo a un ritmo acelerado, debido al impacto de las actividades humanas. En este artículo analizamos y enfatizamos sobre una de las funciones más importantes: la de depuración del agua debido a remoción de contaminantes, quecomprende diversos procesos biológicos y físico-químicos, que se traducen en bienes y servicios ecosistémicos muy valiosos. Para entender esta función, profundizamos en una investigación en el Delta del Paraná, uno de los deltas más importantes del mundo, donde se observó el rol de los humedales de su planicie de inundación en la retención y remoción de nutrientes y contaminantes. La pérdida de humedales en todo el mundo implica la pérdida de sus funciones, por lo que en distintas regiones se vienen realizando esfuerzos para su preservación y restauración, siendo la depuración del agua uno de los servicios más valiosos económicamente que brindan estos ecosistemas. En nuestro medio es necesario profundizar el conocimiento, la concientización y la valoración, con la finalidad de promover su preservación

La investigación social desde la perspectiva bourdieusiana: Desafíos y apuestas

La investigación social desde la perspectiva bourdieusiana: Desafíos y apuestas; Social Research from the Bourdieusian Perspective: Challenges and Proposals Gutiérrez, Alicia Beatriz La investigación social llevada adelante desde la perspectiva bourdieusiana supone enfrentar un conjunto de desafíos que refieren, por una parte, al propio proceso de construcción del objeto y de producción de conocimiento, y, por otra, a su articulación con el contexto de producción de ese conocimiento, como sistema de relaciones. Basándonos en nuestra experiencia en estudios concretos realizados desde este enfoque, proponemos aquí una serie de reflexiones sobre esos desafíos y las decisiones teóricas, metodológicas y empíricas que conllevan. Partiremos de nuestra propuesta de localización de la perspectiva general y de las categorías analíticas bourdieusianas, consideradas como caja de herramientas, y nos detendremos particularmente en las decisiones que hemos tomado en esos procesos y que constituyen, a la vez, apuestas de investigación y de lucha simbólica.; Social research carried out from the Bourdieusian perspective involves facing a set of challenges that refer, on the one hand, to the very process of object construction and production of knowledge and, on the other, to its articulation with the context of production of that knowledge as a system of relationships. Based on the experience of specific studies carried out from this perspective, we propose here a series of reflections on these challenges and the theoretical, methodological, and empirical decisions that they entail. The starting point is a proposal to locate the general perspective and the Bourdieusian analytical categories, considered as a toolbox, and then to focus specifically on the decisions that were made in these processes and that constitute, at the same time, proposals for investigation and symbolic fight.

On some long-forgotten propositions: Reflections on the Epilogue to Arendt's Eichmann in Jerusalem

On some long-forgotten propositions: Reflections on the Epilogue to Arendt's Eichmann in Jerusalem Hilb, Claudia Beatriz This contribution focuses on the last pages of the Epilogue of Eichmann in Jerusalem by Hannah Arendt, but it concerns a question that runs through Arendt’s work practically in its entirety, which can be put as follows: How can we judge when we can no longer rely on the certainties of tradition, when – with the emergence of totalitarianism – the categories and concepts with which we used to judge no longer help us to account for the horrifying reality of crimes of an unknown nature and of criminals who do not comply with the notion of criminals that we used to consider? The text aims to dwell on these somewhat strange final pages of Arendt’s chronicle of Eichmann’s trial to try to see how they nourish our reflection on how to confront an unknown evil of a new kind.

Subasta de inmuebles del Estado, selectividad de la obra pública y adecuación de la normativa urbana: claves para pensar la política de suelo en Argentina y la Ciudad de Buenos Aires entre 2015 y 2019

Subasta de inmuebles del Estado, selectividad de la obra pública y adecuación de la normativa urbana: claves para pensar la política de suelo en Argentina y la Ciudad de Buenos Aires entre 2015 y 2019 Baer, Luis Enrique; D Alessio, Francisco Las políticas de suelo urbano pueden mejorar las condiciones de acceso a un hábitat digno, pero también restringir las posibilidades de acceso residencial y promover procesos de exclusión socio-urbana. En este trabajo se problematiza un tipo específico de política de suelo llevado a cabo en el país y la Ciudad Autónoma de Buenos Aires (CABA) entre 2015 y 2019. Desde una perspectiva que enmarca las políticas de suelo en un contexto político de privatización de bienes comunes, se dimensiona la operatoria de subasta de inmuebles públicos a nivel nacional detallando las cantidades de inmuebles ofertados y los montos recaudados. Luego se hace lo propio en la CABA, comparando la operatoria de subasta con la oferta privada de suelo; y articulándola con la inversión selectiva de la obra pública, los cambios de la normativa urbana y los actores beneficiados por estas iniciativas. Se finaliza el artículo con algunas propuestas de políticas de suelo alternativas que buscan promover una ciudad más justa y democrática.; Urban land policies can improve the conditions of access to a decent habitat, but also restrict the possibilities of residential access and promote socio-urban exclusion processes. In this work, a specific type of land policy carried out in the country and the Autonomous City of Buenos Aires (CABA) between 2015 and 2019 is problematized. From a perspective that frames land policies in a political context of privatization of common goods, the auction operation of public real estate at a national level is dimensioned, detailing the quantities of real estate offered and the total amounts collected. Then the same is done in CABA, comparing the auction operation with the private offer of land; and articulating it with the selective investment of public works, changes in urban regulations and the actors benefited by these initiatives. The article ends with some proposals for alternative land policies that seek to promote a more just and democratic city.

Reflexiones sobre el poder evangélico en América Latina

Reflexiones sobre el poder evangélico en América Latina Goldstein, Ariel Alejandro La derecha católica vinculada al peronismo fue uno de los principales adversarios del argentino-italiano Gino Germani, quien fundó la carrera de sociología en la Universidad de Buenos Aires y fue su primer director. Por aquella misma época, uno de sus cercanos colaboradores, Torcuato Di Tella, señaló que “el estudio científico de la sociedad implica hundir el bisturí de la crítica en tejidos sensitivos y por lo tanto no puede menos que provocar una reacción violenta de los afectados” (Di Tella, citado en Germani, 2013, p. 257). En aquel contexto de posguerra, con los fascismos como telón de fondo de las indagaciones en ciencias sociales sobre el pasado inmediato, Germani se refería a la sociología como una “ciencia de la crisis” que podía plantear interpretaciones y soluciones racionales. Desde esa perspectiva, las ciencias sociales presentan un conflicto con el ejercicio del poder de los referentes religiosos, al buscar establecer racionalidad en la esfera pública y descubrir los mecanismos de construcción del poder y las formas de dominación.

Achievable Energy Efficiency in Massive MIMO: Impact of DAC Resolution and PAPR Reduction for Practical Network Topologies at mm-waves

Achievable Energy Efficiency in Massive MIMO: Impact of DAC Resolution and PAPR Reduction for Practical Network Topologies at mm-waves Schmidt, Christian Andrés; Schmidt, Jorge Friedrich; Figueroa, Jose Luis; Crussiere, M. This letter explores key parameters of a massive MIMO system and their impact on energy efficiency at transmission. In particular, the effect of the digital to analog converter resolution and peak to average power ratio reduction techniques are addressed, in the context of practical user location distributions for both line and non line of sight channels. Results show interesting design trade-offs, and highlight the relevance of an accurate model for the user locations for the correct evaluation of the achievable performance.

Systematics of vibrational properties of Au nanoparticles: a molecular dynamics approach

Systematics of vibrational properties of Au nanoparticles: a molecular dynamics approach Bertoldi, Dalía Surena; Fernandez Guillermet, Armando Jorge This paper reports the results of a Molecular Dynamics (MD) study of the vibrational properties of spherical Au nanoparticles with a number of atoms (N) varying in the range 1985 ≤ N ≤ 53 117. The LAMMPS code is adopted to calculate the vibrational density of states (VDOS), represented by D(ω) versus ω function. Two interatomic potentials, an EAM and a MEAM are used. The first part of the work is devoted to the D(ω) versus ω relation of macroscopic Au, which is obtained by MD simulations as well as by a density-functional-theory calculation using the Vienna Ab Initio Simulation Package and the PHONOPY code. Additional experimental and theoretical results on the VDOS of Au are used to compare with the present results. Next, the effect of changing N and the interatomic potential upon the VDOS of the nanoparticles is established. In particular, the effect of the surface vibrational modes upon the results is discussed. Various moment frequency parameters ωD(j) expressing averages of the D(ω) versus ω function are evaluated, and expressed as Debye temperatures θD(j), using standard relations. Attending to the relevance of these quantities in the description of the thermodynamic properties of macroscopic solids, values of θD(j) corresponding to j = −3, 0, 1, 2 and 4 are reported. On this basis, a picture of the systematic effects of changing N upon the θD(j) values is established both for the EAM and the MEAM potential. In addition, various interrelations between the θD(j) values for nanoparticles are presented. In particular, remarkably simple correlations are reported between the average quantities θD(0), θD(1), θD(2) and θD(4) and θD(−3) i.e., the Debye temperature which accounts for the low-frequency part of the spectrum. Finally, a discussion is reported of the relation between θD(−3) and other properties that are usually adopted as a measure of cohesion in macroscopic solids. To this aim, new correlations involving the nanoscopic counterpart of the temperature of fusion of macroscopic elements as well as the cohesive energy for Au nanoparticles are presented.

Perfil térmico Pedernal

Perfil térmico Pedernal Perfil térmico anual de la temperatura superficial de la localidad de los Berros en Pedernal, San Juan, Argentina. Estos datos permiten ajustar modelos termofisiologicos a escala local

Perfil térmico Matagusanos

Perfil térmico Matagusanos Perfiles térmicos anual de la localidad de Matagusanos, San Juan, Argentina. Esta caracterización temporal de la temperatura del suelo en la superficie en 2 puntos diferentes y en una cueva a 15cm de profundidad ayuda a modelar los recursos térmicos disponibles para los ectotermos de la region.

Macrohongos del NEA 2015-2021

Macrohongos del NEA 2015-2021 Se presenta el listado de especímenes de macrohongos recolectados en localidades del noreste argentino (principalmente provincias de Misioenes, Corrientes y Chaco), en campañas realizadas entre 2015 y 2021.

Bases de información para la construcción de circuitos de acceso y permanencia en escuelas secundarias provinciales: análisis por clúster según indicadores institucionales, de población escolar y del contexto social

Bases de información para la construcción de circuitos de acceso y permanencia en escuelas secundarias provinciales: análisis por clúster según indicadores institucionales, de población escolar y del contexto social Bases en formato .sav de las provincias de Chaco y Misiones elaboradas durante el año 2021, contienen un campo de ID ficticio que permite identificar a casa institución educativa. Cada base cuenta con indicadores institucionales, de población escolar y del contexto social y un campo que permite identificar a los circuitos educativos construidos en cada provincia según la técnica de two step cluster.

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