Cultura cooperativa y gestión empresarial en la cuenca lechera cordobesa-santafecina. Argentina, fines del s. XIX a 1970; Cooperative Culture and Business Management in the Dairy Region of Córdoba and Santa Fe. Argentina, from the End of the 19th Century to 1970 Olivera, Gabriela Este artículo presenta resultados de una investigación basada en fuentes primarias. Revaloriza el conocimiento de procesos históricos espacial y temporalmente particularizados. Apunta a explicar las transformaciones históricas que tenían lugar en la cuenca lechera cordobesa-santafecina en Argentina cuando se intensificaba la actividad agroindustrial bajo el liderazgo de la empresa cooperativa Sancor (Fábrica de manteca Sancor Cooperativas limitadas).; This article presents results of an investigation based on primary sources. Revalues the historical process knowledge particularized space and time. It aims to explain the historical changes taking place in Cordoba- Santa Fe dairy area in Argentina when agroindustrial activity intensified under the leadership of the cooperative enterprise Sancor (Sancor Butter Factory Co Limited).

Performance of low frequency magnetometers to non-sinusoidal magnetic fields Cortés, C. A.; Brüggemeyer, H.; Dib, R.; Mombello, Enrique Esteban; Ratta, Giuseppe This paper presents the second part of a research work dealing with the performance assessment of commercially available magnetometers. The aim of the article is to continue a comparative study of a magnetometer set, but now using non-sinusoidal signals. Nineteen magnetometers were tested using signals with two and more frequency components; some features of the meters were investigated: fft, rms value, peak value and wave capture functions.

El primado del espacio en la fenomenología del cuerpo de Maurice Merleau-Ponty Garcia, Esteban Andres Los trabajos exégeticos acerca de la filosofía de Merleau-Ponty a menudo se refieren a la centralidad que en ésta adquiere la cuestión de la temporalidad. Sin duda, lo hacen apoyándose en el mismo filósofo, quien parece subrayar explícitamente esta primacía de la cuestión del tiempo por ejemplo al afirmar en la primera parte de la Phénoménologie de la Perception que “la ambigüedad del ser-del-mundo se traduce por la del cuerpo, y ésta se comprende por la del tiempo. [...] A partir de este fenómeno central [el tiempo] las relaciones de lo ‘psíquico’ y lo ‘fisiológico’- se vuelven pensables”1 . En su exposición acerca del mundo percibido, en la segunda parte de la obra, Merleau-Ponty reiterará que "la síntesis perceptiva es para nosotros una síntesis temporal, la subjetividad [...] no es nada más que la temporalidad"2 . También afirma que "la síntesis espacial y la síntesis de objeto se fundan en este despliegue del tiempo"3 . Al finalizar la segunda parte de la obra Merleau-Ponty reitera que "si encontramos de nuevo el tiempo bajo el sujeto, si vinculamos a la paradoja del tiempo las del cuerpo, del mundo, de la cosa y del otro, comprenderemos que, más allá, nada hay por comprender"4 . Todos los problemas claves de toda su Fenomenología, según estas afirmaciones, desembocarían y se resolverían aparentemente en torno a la cuestión del tiempo. Sin embargo, nos propondremos primeramente mostrar que posiblemente el mismo filósofo no describía cabalmente en estas afirmaciones el verdadero resultado que arrojarían sus análisis acerca del tiempo y el espacio, la corporalidad y la percepción, ni su específico abordaje de la temporalidad en el capítulo expresamente dedicado al tema, puesto que estos desarrollos no nos guían hacia la conclusión de la necesaria "temporalización" del espacio o del cuerpo, sino en igual o incluso mayor medida, hacia la "espacialización" del tiempo. Observaremos en segundo lugar de qué modo este movimiento de la reflexión merleaupontyana se distancia de la intuición bergsoniana del tiempo como propiedad distintiva de la interioridad de la conciencia, así como de la concepción reticular de la temporalidad husserliana en que los momentos y las perspectivas armonizan entre sí. Por último, el análisis de la particular concepción del espacio como simultaneidad de perspectivas incomposibles desarrollada por el último Merleau-Ponty y relacionada explícitamente con la experiencia onírica e infantil nos permitirá esclarecer ciertas relaciones de cercanía y de contraste con el proyecto freudiano de una topología psíquica.

Exfoliative cytology and titanium dental implants: A pilot study Olmedo, Daniel Gustavo; Nalli, Gabriela; Verdú, Sergio; Paparella, María Luisa; Cabrini, Rómulo L. Background: Oral exfoliative cytology is a diagnostic method that involves the study of cells exfoliated from the oral mucosa. Ions/particles released from metallic implants can remain in the peri-implant milieu. The aim of the present study is to assess the presence of metal particles in cells exfoliated from peri-implant oral mucosa around titanium dental implants. Methods: The study comprised 30 patients carrying titanium dental implants, who had neither a metallic prosthesis nor metal restorations in neighboring teeth. Individuals undergoing orthodontic therapy and those who had oral piercing were also excluded from the study. The study sample included patients with and without peri-implantitis. Cytologic samples of the peri-implant area were collected. Samples of the marginal gingiva on the contralateral side of the implant were taken from the same individuals to serve as control. Cytologic analysis was performed using light microscopy. Titanium concentration was determined using inductively coupled plasma-mass spectrophotometry. Results: Metal-like particles were observed inside and outside epithelial cells and macrophages in cytologic smears of peri-implant mucosa of both patients with and without peri-implantitis. No particles were found in the control cytologic samples. The concentration of titanium was higher in the peri-implantitis group compared with the group without peri-implantitis; no traces of titanium were observed in controls. Conclusions: Regardless of an inflammatory response, ions/particles are released from the surface of the implant into the biologic milieu. Exfoliative cytology is a simple technique that may be used to detect metal particles in cells exfoliated from the peri-implant mucosa.

Evidence of structural changes of an enzymatic extract entrapped into alginate beads Illanes, Cristian Omar; Quiroga, Evelina; Camí, Gerardo Enrique; Ochoa, Nelio Ariel In this work, we analyzed the structural changes of araujiain entrapped into alginate beads. Araujiain is an enzymatic preparation containing three known enzymatic fractions with each fraction individually presenting a similar catalytic performance. Fluorescence and infrared spectroscopy, thermal analysis and residual catalytic activity studies were carried out. A small red shift in the spectrum of araujiain was observed after the entrapment process. Changes in the polarity around the tryptophan (Trp) residues were associated with an enzyme conformational change. From the Fourier transform infrared spectroscopy (FTIR) analysis, it was demonstrated that interactions between the enzyme extract and Ca alginate caused different structural behavior in araujiain. According to the diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) study, it was possible to conclude that a secondary structure with a high α-helical character was responsible for the highest activity of entrapped araujiain. Finally, from thermal analysis measurements, it was proved that entrapment of araujiain augments the thermal stability of both the enzyme extract and Ca alginate, indicating a possible interaction between enzyme extract and its support.

Fungal and mycotoxins contamination in corn silage: Monitoring risk before and after fermentation Keller, L. A. M.; Gonzalez Pereyra, Maria Laura; Keller, K. M.; Alonso, Veronica Andrea; Oliveira, A. A.; Almeida, T. X.; Barbosa, T. S.; Nunes, L. M. T.; Cavaglieri, Lilia Reneé; Rosa, C. A. R. Silage is a widespread practice to preserve forage. Poor storage conditions can lead to mold contamination and mycotoxin production. The aim of this study was to establish the occurrence of toxigenic fungal species and to determine aflatoxins (AFs), ochratoxin A (OTA), fumonisin B1 (FB1) and deoxinivalenol (DON) in corn silage intended for bovines before and after fermentation in farms located in São Paulo and Rio de Janeiro States, Brazil. Fungal counts were done by surface-spread method. Toxigenic ability of isolates was evaluated in vitro. AFs natural contamination was determined by TLC and HPLC. Total fungal counts were generally high. Aspergillus flavus, Penicillium citrinum, and Fusarium verticillioides were the prevalent species. Toxigenic strains were isolated. Aflatoxin levels differed (P < 0.0001) from 2 to 45 μg g-1 and from 2 to 100 μg g-1 in pre and post-fermentation samples, respectively. Ochratoxin A, FB1 and DON levels found in pre-fermentation samples were higher than in post-fermentation (P < 0.0001). Mycotoxins and toxigenic fungi were present before and after fermentation in corn silage intended for bovines in Brazil. Aflatoxin B1 (AFB1) increased during storage whereas OTA, FB1 and DON decreased. Determination of mycotoxin levels and their occurrence in corn silage are important to provide information so that the assessments of risk for animal feed and livestock environment could be made.

Diacronías en negativos de campaña: un recorrido por la historia de la arqueología argentina del NOA a través de sus fotografías de trabajo de campo entre los años 1905 y 1930 Saletta, María José Este artículo se propone indagar el proceso de conformación de la arqueología argentina, como disciplina así como de su objeto de estudio, mediante el análisis de su desarrollo histórico en el Noroeste argentino (en adelante NOA) entre 1905 y 1930, a partir de las fotografías que registraron el trabajo de campo de trece expediciones organizadas por el Museo Etnográfico de la Facultad de Filosofía y Letras de la Universidad de Buenos Aires. En ellas se busca rastrear si, durante el período relevado, hubo variaciones en las prácticas de los investigadores que indiquen el inicio de la aplicación de principios derivados del positivismo y del razonamiento inductivo. En trabajos previos (Saletta 2010, 2011) se presentó un análisis del total de la muestra de imágenes de trabajo de campo de las expediciones organizadas por el Museo Etnográfico durante ese mismo período. En ambos artículos se buscó rastrear la existencia de un habitus de visión disciplinar y, de existir, si éste reflejaba la objetivación del artefacto arqueológico por sobre sus relaciones contextuales. En cambio, en la presente investigación el objetivo consiste en analizar si durante los veinticinco años analizados se inició el proceso de sistematización –el disciplinamiento de la arqueología– en los métodos de trabajo de campo registrados en las fotografías y en el uso de la misma como registro “objetivo” de ese trabajo de campo.

Comparative cytogenetics in Cyclopogon (Orchidaceae) Grabiele, Mauro; Cerutti, Juan Carlos; Hojsgaard, Diego Hernan; Almada, Rubén D.; Daviña, Julio Rubén; Honfi, Ana Isabel A cytotaxonomical description of Cyclopogon (Spiranthinae, Orchidaceae) is carried out through a deep karyotype analysis of four species from NE Argentina. Distinctive karyotype parameters concerning the chromosomes number, morphology, size and symmetry and the genome size associate to each taxon. Cyclopogon calophyllus (2n = 2x =28; 18m + 10sm), C. congestus (2n = 2x = 32; 26m + 6sm), C. elatus (2n = 2x = 28; 18m + 10sm) and C. oliganthus (2n = 4x = 64; 40m + 24sm) possess symmetrical karyotypes (i-mean = 40. 01-42. 84; A1 = 0. 24-032; r>2 = 0. 06-0. 29) and excluding C. congestus (A2 = 0. 26; R = 2. 62) unimodality is the rule (A2 = 0. 12-0. 20; R = 1. 73-1. 92). Diploid taxa show a terminal macrosatellite in the m pair no. 2 (large arm) and share a comparable mean chromosome length (ca. 2. 75 μm) and genome size (ca. 40 μm), superior to the tetraploid C. oliganthus (ca. 2 and 32 μm, respectively). The novel data added to preceding cytological, morphological and molecular approaches involving Cyclopogon and those related taxa of Spiranthinae largely based on x = 23 support the hypothesis that the unusual 2n and the karyotype morphology of Cyclopogon is an evolutionary advance within Spiranthinae with a basic reduction to x = 14 or 16 by chromosome fusions. A polyploid-dysploid series added to dibasic hybridization explain the extant 2n diversity though a paleopolyploid series on x = 7-8 is also possible. © 2013 Versita Warsaw and Springer-Verlag Wien.

El Desarrollismo y el problema agrario durante las décadas de 1950 y 1960; Development Policy and Agrarian Problems during the 1950s and 1960s Lazzaro, Silvia Beatriz El propósito del artículo se orienta al estudio de la proyección de las ideas desarrollistas sobre la economía y la sociedad argentina, particularmente en el ámbito del sector agropecuario durante las décadas de 1950 y 1960: las proposiciones, las estrategias implementadas y las secuelas más significativas. El criterio a utilizar pone énfasis en la consideración de las políticas públicas, no meramente como procesos determinados por factores que operan dentro de los límites territoriales y legales del Estado, sino analizadas como componentes y dimensiones de una red global de relaciones de poder e intereses que condicionan la lógica y la racionalidad que definen las articulaciones entre el Estado y la sociedad dentro del marco internacional.; The purpose of this article is to study the projection of development ideas on the Argentinean economy and society, particularly withinthe sphere of the dynamic agricultural sector,from 1950 to 1960: the goals, the strategiesimplemented and the most significant effects.The criterion to be used emphasizes the consideration of public policies not only as processesdetermined by factors that operate within theterritorial and legal limits of the state but analyzed as components and dimensions of aglobal network of power relations and intereststhat determine the logic and rationality thatdefine the links between state and societywithin the international framework.

Updated analyses of temperature and precipitation extreme indices since the beginning of the twentieth century: the HadEX2 dataset Donat, M. G.; Alexander, L. V.; Yang, H.; Durre, I.; Vose, R.; Dunn, R. J. H.; Willet, K. M.; Aguilar, E.; Brunet, M.; Caesar, J.; Hewitson, B.; Jack, C.; Klein Tank, A. M. G.; Kruger, A. C.; Marengo, José A.; Peterson, T. C.; Renom, Madeleine; Oria Rojas, C.; Rusticucci, Matilde Monica; Salinger, J.; Elrayah, A. S.; Sekele, S. S.; Srivastava, A. K.; Trewin, B.; Villarroel, C.; Vincent, L. A.; Zhai, P.; Zhang, X.; Kitching, S. In this study, we present the collation and analysis of the gridded land-based dataset of indices of temperature and precipitation extremes: HadEX2. Indices were calculated based on station data using a consistent approach recommended by the World Meteorological Organization (WMO) Expert Team on Climate Change Detection and Indices, resulting in the production of 17 temperature and 12 precipitation indices derived from daily maximum and minimum temperature and precipitation observations. High-quality in situ observations from over 7000 temperature and 11,000 precipitation meteorological stations across the globe were obtained to calculate the indices over the period of record available for each station. Monthly and annual indices were then interpolated onto a 3.75° × 2.5° longitude-latitude grid over the period 1901–2010. Linear trends in the gridded fields were computed and tested for statistical significance. Overall there was very good agreement with the previous HadEX dataset during the overlapping data period. Results showed widespread significant changes in temperature extremes consistent with warming, especially for those indices derived from daily minimum temperature over the whole 110 years of record but with stronger trends in more recent decades. Seasonal results showed significant warming in all seasons but more so in the colder months. Precipitation indices also showed widespread and significant trends, but the changes were much more spatially heterogeneous compared with temperature changes. However, results indicated more areas with significant increasing trends in extreme precipitation amounts, intensity, and frequency than areas with decreasing trends.

Los hermanos sean unidos... Frontera e identidad. Misiones 1870- 1953 Rodríguez, Lisandro Ramon La actual provincia fronteriza de Misiones —en el nordeste argentino (nea)— constituyó hasta fines del siglo xix una zona de disputa que involucró a la Argentina, Paraguay y Brasil. El objetivo de estos países consistía en ejercer algún control sobre este espacio, cuya ubicación estratégica lo convertía en un punto clave del tráfico comercial de la región. La trama de relaciones regionales está enraizada con mayor profundidad que los límites fijados por los nuevos Estados; como se demuestra en el caso de Misiones, donde la existencia de numerosos circuitos de intercambio, códigos e historias compartidas da cuenta del carácter socio- histórico de la frontera y de la construcción social del espacio. El objetivo de este ensayo histórico, es analizar el accionar del Estado argentino en los procesos de definición de las fronteras de Misiones, particularmente en la demarcación de límites con Brasil y Paraguay. El enunciado de que las fronteras interestatales “no son naturales ni esenciales”, sino producto de acuerdos históricos surgidos de relaciones de fuerza entre los Estados y su relación con las poblaciones locales, es uno de los componentes conceptuales de este estudio.

Comunicación para el cambio social y educación.ambiental: reflexiones para la construcción colectiva del desarrollo a partir de un estudio de caso en Salta, Argentina; Communication for social change and environmental education: thoughts for the collective construction of development from a case in Salta, Argentina Elbirt, Ana Laura En este artículo presenta reflexiones acerca de las contribuciones de la educación ambiental como espacio de formación política necesario ante los conflictos socio-ambientales actuales. Para ello se expone, con perspectiva histórica, las distintas concepciones de desarrollo, desde las nociones economicistas hasta las actuales sobre el lugar central de la participación y la construcción de ciudadanía como condición para el desarrollo local. Las reflexiones teóricas expuestas están hechas sobre la base de un estudio de caso en la capital de la provincia de Salta. Este estudio se centró en el análisis de la primera medida gubernamental de Recolección Diferenciada de los Residuos Domiciliarios en la ciudad. Se trabajó la temática de la educación ambiental , a partir de los siguientes ejes: planificación participativa en los proyectos, capital social, rol del comunicador y medios de comunicación como promotores del desarrollo.; In this article we present reflections about the contributions of environmental education as a space for political formation necessary to the current socio-environmental conflicts. So we expose historical perspective of the different conceptions of development, since economic notions to the current on the central place of participation and the construction of citizenship as a condition for local development. Theoretical reflections are made on the basis of a case study in the capital of the province of Salta. This study focused on the analysis of the first public politic for differentiated collection of the domestic waste in the city. We worked with the following subjects: participative projects planning, social capital, role of communicator and the media as promoters of development.; Cet article propose des réflexions au sujet des contributions de l éducation sur l environnement, comme un espace de formation politique qui se rend nécessaire devant les conflits socio-environnementaux de nos jours. Pour cela, on expose, avec une perspective historique, les différentes conceptions du développement, depuis les notions de l économie classique d avant jusqu á celles d aujourd hui qui versent sur la place centrale de la participation et la construction de citoyenneté, comme l'une des conditions pour le développement local. Les réflexions théoriques qui y sont exposées ont été extraites sur la base d'une étude de cas dans la capitale de la province de Salta, Argentine. Cette étude a été faite autour de l analyse de la premiére disposition gouvernementale sur le Ramassage Différencié des Résidus Domiciliaires de la ville. On a travaillé la thématique de « l éducation á l environnement », á partir des points qui suivent : planification participative dans les projets, capital social, róle du communicateur et des médias en tant que promoteurs du développement.

Vulneración de derechos y alternativas de exigibilidad en salud comunitaria; Right's infirgment and alternatives to exigibility in communitarian health Zaldua, Graciela; Longo, Roxana; Sopransi, María Belén; Lenta, María Malena Desde la Epidemiología Crítica, el proceso de salud-enfermedad-atención-cuidado es considerado como un proceso singular y colectivo que acontece en un territorio. La Psicología Crítica aporta tanto la elucidación de dimensiones participativas y dialogales, como el compromiso con la transformación de contextos socioeconómicos, ecológicos, simbólicos y subjetivos. Ambas perspectivas aportan al abordaje de la salud como un campo de confluencia e intersección de sentidos, prácticas y saberes de diferentes actores sociales en territorios particulares. Con un enfoque cualitativo y la modalidad de estudio de casos múltiple, este trabajo se propone elucidar obstáculos y facilitadores en la exigibilidad de la salud como derecho en las comunas 3 y 4 de la Ciudad de Buenos Aires. Entre los resultados se visibilizaron como principales obstáculos: aspectos socioeconómicos, institucionales, epistémicos y tecnocráticos. Mientras que la existencia de actores con implicación crítica y el sostén de redes sociales-comunitarias aparecieron como principales facilitadores en el acceso al derecho a la salud.; From Critical Epidemiology, health-disease-care process is considered a singular and collective process that occurs in a territory. Critical Psychology brings elucidating of participatory, dialogic and commitment dimensions to transformation of socio-economic, ecological, symbolic and subjective contexts. Both approaches contribute to addressing health as a field of convergence and intersection of meanings, practices and knowledge of different social actors in specific territories. With a qualitative approach and a multiples cases study, this paper intends to elucidate barriers and facilitators in the exigibility of health's right in Buenos Aires City, districts 3 and 4. As results it became visible socio-economic, institutional, epistemological and technocratic dimensions as obstacles; while actors with critical involvement and community social networks appeared as main facilitators in accessing to health's right.

El enfrentamiento discursivo en el proceso de autonomización sindical de los trabajadores del Subterráneo de Buenos Aires (2009-2010); Discursive confrontation in the process of union autonomy of the Buenos Aires subway workers (2009‐2010) Artese, Matias Cosme; Castro Rubel, Jorge Daniel Luego de varios años de mantener una tensa relación con la dirección del sindicato que los representaba, la Unión Tranviarios Automotor (UTA), los trabajadores del Subterráneo de Buenos Aires decidieron en febrero de 2009 escindirse del mismo y conformar la Asociación Gremial de Trabajadores del Subterráneo y el Premetro (AGTSyP). A partir de allí, los trabajadores de este sector iniciaron un proceso de luchas -que los enfrentó principalmente con la UTA, el Estado nacional y la empresa concesionaria del servicio de Subtes- en la dirección de obtener el reconocimiento de su nuevo sindicato. En este artículo nos proponemos explorar el proceso de luchas a través del plano discursivo. El conflicto fue rastreado a lo largo de una periodización que atraviesa los años 2009 y 2010. Tomando como soporte el diario La Nación, construimos una base de declaraciones contenciosas que nos permitió analizar las personificaciones involucradas, sus destinatarios y sus objetivos.; After several years of maintaining a tense relationship with the leadership of the union that represented the Unión Tranviarios Automotor (UTA), workers in the Buenos Aires Underground in February 2009 decided to secede from it and form Asociación Gremial de Trabajadores del Subterráneo y el Premetro (AGTSyP). From there, workers in this sector began a process of struggle -that confronted primarily with UTA, the national state and the concessionaire-Subway service in the direction of obtaining recognition of their new union. In this article we propose to explore this process of struggle through the discursive level. The conflict was tracked over a periodization that spans the years 2009 and 2010. Taking as support the daily La Nación, we build a base of contentious statements which allowed us to analyze the personifications envolved, their recipients and the sense of their actions.

Endoparasitic infections in dogs from rural areas in the Lobos District, Buenos Aires province, Argentina Dopchiz, Marcela Cecilia; Lavallén, Carla Mariela; Bongiovanni, Roberto Antonio; Gonzalez, Patricia Verónica; Elissondo, María Celina; Yannarella, Francisco; Denegri, Guillermo Maria Dogs are definite hosts for several zoonotic helminthes and protozoan. Rural areas from the Lobos District in the northeast of Buenos Aires province, Argentina, are mainly used for livestock activity, increasing in this way the number of dogs on farms as well as the human risk of parasitic infections. The aims of this research were to evaluate the endoparasitic infections in dogs from farms in the Lobos District and analyze their zoonotic importance as well as several risk practices and habits of the rural population. Forty-two dog fecal samples obtained in 21 farms were analyzed through coproparasitological methods and coproantigen tests, which resulted in an overall parasite prevalence of 69.05% and 80.95% of the parasitized farms. The most frequent parasites were Trichuris vulpis and Eucoleus aerophila (26.19%), Echinococcus granulosus (19.05%), Uncinaria stenocephala and coccids (14.29%). The analysis of epidemiological files showed several habits of the rural population considered as risk factors associated with the presence of fecal samples parasitized and the presence of E. granulosus on the farms. It is clear that people involved with the farms studied were exposed to several helminthes that could cause serious diseases like cystic echinococcosis, which can become an important public health issue and affect the economy worldwide; Os cães são hospedeiros definitivos de vários helmintos e protozoários zoonóticos. As áreas rurais do distrito de Lobos, no nordeste da província de Buenos Aires, Argentina, destinam-se principalmente à atividade pecuária aumentando desta forma o número de cães em fazendas, bem como o risco humano de infecções parasitárias. Os objetivos desta pesquisa foram avaliar as infecções endoparasitas em cães de fazendas do distrito de Lobos e analisar a sua importância zoonótica, bem como as práticas de risco e hábitos da população rural. Quarenta e duas amostras de fezes de cães obtidos em 21 fazendas foram analisadas pelos métodos coproparasitológicos e testes de coproantígenos, resultando numa prevalência de parasitas de 69,05% e 80,95% das propriedades parasitados. Os parasitas mais frequentes foram Trichuris vulpis e Eucoleus aerophila (26,19%), Echinococcus granulosus (19,05%), Uncinaria stenocephala e coccídeos (14,29%). A análise dos arquivos epidemiológicos mostraram vários hábitos da população rural como fatores de risco associados com a presença de amostras fecais parasitadas e a presença de E. granulosus em propriedades rurais. É evidente que as pessoas das fazendas estudadas foram expostas a vários helmintos que podem causar doenças graves como equinococose cística, que constitui importante problema de saúde pública e econômico a nível mundial.

The role of ad-atoms in the coalescence of alkanethiol-passivated gold nanoparticles Gutierrez Wing, C.; Olmos Asar, Jimena Anahí; Esparza, R.; Mariscal, Marcelo; Yacaman, M. J. In the present work we show how the role of ad-atoms and surface imperfections play a key role during the coalescence of thiol-passivated Au nanoparticles (NPs) below 4 nm in diameter. Using spherical aberration corrected scanning transmission electron microscopy (STEM) with ultra-high resolution and computer simulations we reveal the main structural and energetic changes throughout the diffusion/migration of surface atoms during coalescence of monolayer-protected NPs. The sintering process of nanoparticles with similar size (diameter) follows a neck-formation mechanism. However, in the case of thiol-protected Au NPs with different size (i.e. with dissimilar surface curvature) the Ostwald ripening mechanism has been detected with atomic resolution in situ STEM measurements for the first time. In particular we have observed how the larger particles grow in size at the expense of the smaller ones, until the latter completely disappear. The experimental findings have been supported with the aid of state-of-the-art computer simulations.

Photoreduction of aliphatic and aromatic thioketals: new access to the reduction of carbonyl groups by a desulfurization chain process Oksdath Mansilla, Gabriela; Argüello, Juan Elias; Peñeñory, Alicia Beatriz Aromatic and aliphatic ketones can be converted to methylene groups by desulfurization of the corresponding dithioketals in moderate to good yields. The reaction proceeds by photoinduced electron transfer from tert-BuOK in the presence of 1,4-dicyclohexadiene as hydrogen atom donor. The diene is able to trigger and keep a chain process by hydrogen transfer–proton transfer reactions.

Dwarf galaxies and the cosmic web Benítez Llambay, Alejandro; Navarro, Julio F.; Abadi, Mario Gabriel; Gottlöber, Stefan; Yepes, Gustavo; Hoffman, Yehuda; Steinmetz, Matthias We use a cosmological simulation of the formation of the Local Group of Galaxies to identify a mechanism that enables the removal of baryons from low-mass halos without appealing to feedback or reionization. As the Local Group forms, matter bound to it develops a network of filaments and pancakes. This moving web of gas and dark matter drifts and sweeps a large volume, overtaking many halos in the process. The dark matter content of these halos is unaffected but their gas can be efficiently removed by ram pressure. The loss of gas is especially pronounced in low-mass halos due to their lower binding energy and has a dramatic effect on the star formation history of affected systems. This "cosmic web stripping" may help to explain the scarcity of dwarf galaxies compared with the numerous low-mass halos expected in ΛCDM and the large diversity of star formation histories and morphologies characteristic of faint galaxies. Although our results are based on a single high-resolution simulation, it is likely that the hydrodynamical interaction of dwarf galaxies with the cosmic web is a crucial ingredient so far missing from galaxy formation models.

Integrating mitochondrial energetics, Redox and ROS metabolic networks: a two-compartment model Kembro, Jackelyn Melissa; Aon, Miguel A.; Winslow, Raimond L.; O'Rourke, Brian; Cortassa, Sonia del Carmen To understand the mechanisms involved in the control and regulation of mitochondrial reactive oxygen species (ROS) levels, a two-compartment computational mitochondrial energetic-redox (ME-R) model accounting for energetic, redox, and ROS metabolisms is presented. The ME-R model incorporates four main redox couples (NADH/NAD+, NADPH/NADP+, GSH/GSSG, Trx(SH)2/TrxSS). Scavenging systems—glutathione, thioredoxin, superoxide dismutase, catalase—are distributed in mitochondrial matrix and extra-matrix compartments, and transport between compartments of ROS species (superoxide: O2⋅−, hydrogen peroxide: H2O2), and GSH is also taken into account. Model simulations are compared with experimental data obtained from isolated heart mitochondria. The ME-R model is able to simulate: i), the shape and order of magnitude of H2O2 emission and dose-response kinetics observed after treatment with inhibitors of the GSH or Trx scavenging systems and ii), steady and transient behavior of ΔΨm and NADH after single or repetitive pulses of substrate- or uncoupler-elicited energetic-redox transitions. The dynamics of the redox environment in both compartments is analyzed with the model following substrate addition. The ME-R model represents a useful computational tool for exploring ROS dynamics, the role of compartmentation in the modulation of the redox environment, and how redox regulation participates in the control of mitochondrial function.

Supramolecular complexes of maltodextrin and furosemide polymorphs: a new approach for delivery systems Garnero, Claudia; Chattah, Ana Karina; Longhi, Marcela Raquel We present new supramolecular complexes of two different solid forms of furosemide (I or II) with maltodextrin, in order to explore their application as delivery systems improving the bioavailability of the drug. The complexation in solution was evaluated by 1H nuclear magnetic resonance experiments and phase solubility studies. The products in solid state were exhaustively characterized by using spectroscopic techniques (13C solid state nuclear magnetic resonance, infrared, scanning electron microscopy, X-ray powder diffractometry) and thermal analysis. 1H relaxation times experiments gave further support in distinguishing the new solid forms. Dissolution studies in simulated gastric fluid showed that both supramolecular complexes presented significant increase in the dissolution, while the corresponding physical mixtures exhibited the most discriminating conditions between the furosemide forms I and II. Our results suggest the enhancement of the solubility and the dissolution of furosemide in the new complexes, making them promising candidates for the preparation of alternative matrices in oral pharmaceutical formulations.