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Controlling Rotavirus-associated diarrhea: Could single-domain antibody fragments make the difference?

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Controlling Rotavirus-associated diarrhea: Could single-domain antibody fragments make the difference?; Hacia el control de la diarrea por rotavirus A: ¿podrían los nanoanticuerpos VHH marcar la diferencia? Maffey, Lucía; Vega, Celina Guadalupe; Parreño, Gladys Viviana; Garaicoechea, Lorena Laura Group A Rotavirus (RVA) remains a leading cause of severe diarrhea and child mortality. The variable domain of camelid heavy chain antibodies (VHH) display potent antigen-binding capacity, have low production costs and are suitable for oral therapies. Two sets of anti-RVA VHHs have been developed: ARP1-ARP3; 2KD1-3B2. Here, we explore the potential of both sets as a prevention strategy complementary to vaccination and a treatment option against RVA-associated diarrhea in endangered populations. Both sets have been expressed in multiple production systems, showing extensive neutralizing capacity against strains of RVA in vitro. They were also tested in the neonatal mouse model with various degrees of success in preventing or treating RVA-induced diarrhea. Interestingly, mitigation of the symptoms was also achieved with freeze-dried ARP1, so that it could be applied in areas where cold chains are difficult to maintain. 3B2 was tested in a pre-clinical trial involving gnotobiotic piglets where it conferred complete protection against RVA-induced diarrhea. ARP1 was used in the first clinical trial for anti-RVA VHHs, successfully reducing stool output in infants with RVA diarrhea, with no detected side effects.

Characterization of the Genetic Diversity of Trachemys dorbigni and Phrynops hilarii

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Characterization of the Genetic Diversity of Trachemys dorbigni and Phrynops hilarii Guidetti, Brenda Yamile; Siroski, Pablo Ariel; Amavet, Patricia Susana The utilization of RAPD and ISSR molecular markers is proposed to initiate studies of genetic variability in Phrynops hilarii (Chelidae) and Trachemys dorbigni (Emydidae), two species of fresh water turtles distributed in South America. Three primers of RAPD and four of ISSR were selected and the amplified products of these markers were evaluated by electrophoretic runs in agarose and polyacrylamide gels. The levels of heterozygosity, Shannon index and different allele numbers were slightly higher in P. hilarii for both types of markers. Levels of polymorphism were also higher in P. hilarii than T. dorbigni and both were elevated compared to those recorded for other species. The fact that similar results were obtained with both types of markers for all estimates of diversity highlights the usefulness and validity of the RAPD technique. The molecular markers used were found potentially useful for analysing future temporal and spatial distribution of genetic diversity in both species, expanding scales work.

Elementos de respuesta a estrés en el ovario y su implicancia en la fisiopatología ovárica en bovinos.

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Elementos de respuesta a estrés en el ovario y su implicancia en la fisiopatología ovárica en bovinos. Amweg, Ayelen Noelia; Salvetti, Natalia Raquel; Rey, Florencia; Ortega, Hugo Hector En respuesta a varios estresores, la hormonaadrenocorticotrópica estimula la síntesis y secreción de los glucocorticoides,los cuales pueden afectar la reproducción directamente por acción sobre el ejehipotálamo-hipófisis-ovario. En este sentido, es importante destacar que laovulación ha sido descripta como un proceso inflamatorio localizado, donde unasucesión de eventos lleva a la degradación proteolítica de un punto específicode la pared folicular para permitir la salida del ovocito. Por lo tanto, elcortisol liberado a causa del estrés podría actuar a nivel del sitio ovulatorioinhibiendo la ovulación al producir efectos antiinflamatorios locales. Si bienno ha sido demostrado que el ovario sea capaz de producir glucocorticoides denovo, la hormona adrenocorticotrópica, a través de su unión a los receptores demelanocortinas en el ovario bovino, es capaz de estimular la secreción dehormonas esteroides tanto in vivo como in vitro, principalmente la secreción decortisol, y producir cambios en la expresión de las enzimas11β-hidroxiesteroide deshidrogenasas responsables de la activación/inactivacióndel cortisol. Nuestros resultados indican que la hormona adrenocorticotrópicapuede estar implicada en los mecanismos regulatorios relacionados a la funciónovárica asociados con la ovulación, la esteroidogénesis y la fisiopatología dediferentes enfermedades reproductivas en bovinos.

Una "Casa de Piedra" en el sudoeste del Chubut

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Una "Casa de Piedra" en el sudoeste del Chubut Perez, Cecilia Beatriz; Castro, Analia; Casanueva, María Laura El artículo presenta las primeras etapas de excavación del sitio Casa de Piedra de Roselló, una cueva utilizada como habitación hasta el siglo XX. Ubicada en el ecotono estepa-bosque patagónico, cuenta con fuentes de agua cercanas y otros recursos naturales aptos para la habitación humana.

El nazismo como Stimmung: Los textos políticos del joven Emmanuel Levinas

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El nazismo como Stimmung: Los textos políticos del joven Emmanuel Levinas Rossi, Luis Alejandro El artículo reconstruye la interpretación del nacionalsocialismo derivada de los textos que Emmanuel Levinas publica en 1933 y 1939. En ella hay una primera confrontación con la filosofía de Martin Heidegger, en la medida en que el pensador francés buscó hallar el nexo de sentido que unía al nacionalsocialismo como «paganismo» con la afirmación del ser que creía encontrar en el pensamiento de Heidegger. Se examina la interpretación que hace Levinas de la tradición judeocristiana como opuesta al «paganismo» y qué contenidos atribuye el filósofo francés a esa tradición.

Circulación de información y representaciones del trabajo en el servicio

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Circulación de información y representaciones del trabajo en el servicio Gorban, Debora; Tizziani, Ania El trabajo en el servicio doméstico también transcurre en espacios que trascienden los límites de los domicilios particulares. Si bien a veces se trata de lugares en los que se permanece por poco tiempo, constituyen puntos de encuentro con otras trabajadoras que posibilitan el intercambio de experiencias de trabajo, intercambios en los que circula información sobre la actividad que resulta de un valor central para estas mujeres. Así, la circulación de información se insinúa como un componente de importancia tanto en la configuración de las relaciones de trabajo en las que se insertan las mujeres empleadas en el servicio doméstico, como en las posibilidades de organización colectiva. Sobre la base de un estudio cualitativo, el objetivo de este artículo es indagar en torno de la manera en que esta información afecta la configuración de la relación laboral entre trabajadoras y empleadores/as y en las condiciones de trabajo de las primeras. Para ello, en la primer sección nos centraremos en caracterizar la manera en que se configura el trabajo en el sector en la Argentina y los desafíos que esa configuración plantea a la organización colectiva de las trabajadoras. En un segundo momento, nos centraremos en el análisis de los espacios que habilitan los intercambios entre las empleadas domésticas, el tipo de información que allí circula y la especificidad del rol que cumplen las organizaciones colectivas. Abordaremos, por último, la manera en que esa información es movilizada por las empleadas en sus experiencias cotidianas de trabajo.; Working in the domestic service implies along with the tasks carried out in the particular address of the employer, displaying some others in spaces that extend this particular addresses limits. Although sometimes workers do not spend too much time in these places, they constitute points of contact with other workers, making possible the interchange of work experiences. And in these interchanges there is a circulation of information on the activity that has a central value for these women workers. In this way is that the circulation of information is insinuated not only as a component of importance in the configuration of the relationships in which domestic workers are inserted, but also in their possibilities of collective organization. Based on a qualitative study, the aim of this article is to analyse the way in which this information affects the configuration of the labor relation between workers and their employers and the working conditions of the first. In the first section of the article we will concentrate in how is characterized domestic work in Argentina and the challenges that its configuration raises to the collective organization process of the workers. At a second moment, we will concentrate in the analysis of the spaces that make possible the interaction between domestic workers, the type of information that circulate there and the specificity of the roll that collective organizations accomplished. In the last part we will depict the way in which these workers in their daily work experiences mobilize that information.; L'exercice du travail dans les services domestiques inclut des activités qui débordent les limites du domicile privé des employeurs. Les commerces, les espaces communs des immeubles, les aires de jeux pour enfants constituent des lieux de travail pour les employées domestiques et des espaces de rencontre avec d'autres travailleuses qui rendent possible des échanges sur leurs expériences de travail. La circulation d'information apparaît comme une dimension importante concernant la configuration des relations de travail des femmes qui s'insèrent dans le secteur, ainsi que les possibilités d'organisation collective de cette catégorie de travailleuses. Sur la base d'une étude qualitative, cet article s'interroge sur les effets de la circulation d'information sur la configuration des relations que les employées établissent avec leurs employeurs et sur leurs conditions de travail. Dans la première section, nous cherchons à caractériser ce secteur en Argentine et analyser les défis de l'organisation collective de ces travailleuses. Dans une deuxième section, nous étudions les espaces qui rendent possible les échanges entre les travailleuses, le type d'information qu'y circule et le rôle joué par les organisations syndicales dans ce circuit. Nous analysons, enfin, la manière dont ces informations sont mobilisées par les travailleuses au cours de leurs expériences quotidiennes de travail.

Trilobites epipelágicos del Ordovícico de Perú y Bolivia

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Trilobites epipelágicos del Ordovícico de Perú y Bolivia Gutierrez Marco, Juan Carlos; Rábano, Isabel; Aceñolaza, Guillermo Federico; Chacaltana, César Lostelefínidos espipelágicos son trilobites raros en Sudamérica, donde se conocen pocos ejemplares en elOrdovícico de la Precordillera, la cuenca de Famatina, la Puna oriental y la Cordillera Oriental argentina. En este trabajo se presentan los registros más septentrionales de los géneros Carolinites y Oopsites. El Ordovícico Inferior de la cuenca andina central, procedentes de la Formación Sella del sur de Bolivia(Carolinites genacinaca Ross s.l.) y de la Formación San José del suroeste del Perú (Oopsites sp. nov). El exiguo registro de estos telefínidos se halla vinculado con corrientes de aguas cálidas,que esporádicamente se dirigían hacia el sur a lo largo de lmargen gondwánico, transportando trilobites paleotropicales hacia paleolatitudes más elevadas con aguas templadas a frías.; Epipelagic telephinid trilobites rarely occur in the Ordovician of South America, being represented byfew specimens recorded from the ArgentinianPrecordillera, the Famatina Basin, eastern Puna and Cordillera Oriental. We here report the northernmost occurrences of the genera Carolinites and Oopsites in the Central Andean Basin, coming from the Lower Ordovician rocks of the Sella Formation of southern Bolivia (Carolinites genacinaca Ross s.l.) and from the San José Formation of southwestern Peru (Oopsites sp.nov). The scarce record of these telephinids has been related to warm water currents, that sporadically moving southwards along the Gondwanan margin,carrying palaeotropical trilobites into more temperate to cool-­‐water higher palaeolatitudes.

Función barorrefleja y variabilidad de la presión arterial evaluadas desde el consultorio clínico

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Función barorrefleja y variabilidad de la presión arterial evaluadas desde el consultorio clínico; Baroreflex function and blood pressure variability evaluated in the clinical consulting room Rodeles Antonelli, Luz María; Vicco, Miguel Hernán; Dorigo, Catalina Inés; Melo, Ludmila; Vivalda, Natalia Belén; Pessolani, María Florencia; Musacchio, Héctor Mario La variabilidad de la frecuencia cardíaca (FC) y de la presión arterial (PA) se evalúan por lo general mediante Holter y monitorización ambulatoria de la presión arterial (MAPA). Estos exámenes no se encuentran disponibles generalmente en el medio hospitalario. Objetivo: Evaluar los parámetros de la función barorrefleja determinada por electrocardiograma basal y durante la realización de la maniobra de Valsalva (MV), con los indicadores de variabilidad de FC por Holter y PA por MAPA. Métodos: Estudio transversal, observacional. Se incluyeron prospectivamente pacientes adultos, sin enfermedades ni utilización de fármacos que modifiquen la FC o la PA. Se realizó electrocardiograma (ECG) basal de 10 s. La respuesta cronotrópica se evaluó mediante MV estandarizada registrada en ECG. Se realizaron MAPA y Holter de 12 horas. Resultados: Se estudiaron 50 pacientes, observándose que el SDNN del ECG de 10 s y la variación de la FC intra/previa a la MV podrían resultar de utilidad para estimar el valor del SDNN del Holter, parámetro asociado con hipofunción barorrefleja y aumento de riesgo vascular. En cuanto a la PA, no pudo demostrarse mayor variabilidad de PA sistólica por MAPA en los pacientes con disminución de la respuesta cronotrópica. Conclusión: Indicadores simples de determinar en el consultorio clínico realizando ECG y MV podrían complementar la evaluación del riesgo cardiovascular y contribuir a seleccionar aquellos pacientes en quienes sería conveniente efectuar un estudio de MAPA, tanto para diagnóstico como para seguimiento.; Heart rate (HR) and blood pressure (BP) variability is generally assessed with Holter and ambulatory blood pressure monitoring (ABPM). These tests are not generally available in hospitals.Objective:To evaluate the baroreflex function parameters determined by baseline electrocardiogram and during Valsal vamaneuver (VM) with the variability indicators in HR from Holter and BP from ABPM.Methods: Cross sectional,observational study. Adult patients without conditions or drugs that might modify the HR and/or BP were included. Basal ECG in lead II for 10 sec was obtained. In order to evaluate chronotropic response, we performed standardized VM recorded in ECG. 12-hour ABPM and Holter were performed. Results: 50 patients were studied, showing that 10 sec ECG SDNN and variation of HR intra/pre-MV could be useful to estimate the value of SDNN Holter, parameter associated with baroreflex disfunction and increased vascular risk. In regard to BP, there was no correlation between ABPM BP variability and pathological chronotropic response in VM. Conclusion: Simple to determine indicators from ECG and MV can be useful in patients with suspected augmented lability of BP. They could complement cardiovascular risk assessment, and could assist the clinician in selecting those patients in which it should be more useful and cost effective to carry out an ABPM, both for diagnosis and monitoring.

La gobernabilidad local a través del prisma de la intervención comunal (Buenos Aires, 1954)

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La gobernabilidad local a través del prisma de la intervención comunal (Buenos Aires, 1954); A governabilidade local sob o prisma da intervenção municipal (Buenos Aires, 1954) Salomón, Alejandra Laura El debate acerca de la construcción del poder político durante la etapa peronista (Argentina, 1946-1955) provee buenas razones para detenerse a analizar el fenómeno en la esfera municipal. En este marco, el artículo analiza la política ?desde abajo? en situaciones conflictivas, en torno a las intervenciones comunales (decretadas en 1954) de tres localidades de la provincia de Buenos Aires presididas por intendentes oficialistas (Carlos Casares, Bartolomé Mitre y Luján). Con fuentes periodísticas y gubernamentales, el fin es estudiar la relación entre el poder provincial y el poder municipal con la atención puesta en aspectos inherentes al funcionamiento político del gobierno local. Para ello se examinan los motivos y justificaciones de las intervenciones y se focaliza en la gobernabilidad local, tanto desde el punto de vista de la representación como de la participación. ¿En qué medida el conflicto local y la ruptura de alineamientos políticos incidieron en la dinámica que adquirió la gobernabilidad en las comunas y, en última instancia, en el decreto de intervención? ¿De qué modo en un contexto político tenso militantes y dirigentes locales conjugaron la lealtad hacia la conducción del movimiento peronista y hacia figuras locales con capital social sustentado en vínculos tejidos en el Municipio?; O debate sobre a construção do poder político durante a era peronista (Argentina, 1946-1955) proporciona uma boa razão para nos atermos e analisarmos o fenômeno em nível municipal. Neste contexto, o artigo analisa a política “por baixo” em situações de conflito relacionadas às intervenções municipais (decretadas em 1954) em três localidades da província de Buenos Aires presididas por intendentes lealistas (Carlos Casares, Bartolome Mitre e Luján). Com base em fontes de mídia e do governo, o objetivo consiste em estudar a relação entre o poder provincial e o poder municipal, com foco em aspectos inerentes ao funcionamento político do governo local. Para tanto, são examinadas as motivações e justificativas das intervenções, com foco na governabilidade local, tanto do ponto de vista da representação quanto da participação. Em que medida o conflito local e a ruptura de alianças políticas afetaram a dinâmica da governabilidade nos municípios e, em última instância, o decreto de intervenção? De que modo, em um contexto de tensão, militantes e líderes locais conjugaram a lealdade com o movimento peronista e com figuras locais, cujo capital social se baseia em vínculos criados nesses municípios?

Horticultura de La Plata (Buenos Aires): Modelo productivo irracionalmente exitoso

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Horticultura de La Plata (Buenos Aires): Modelo productivo irracionalmente exitoso; Horticulture in La Plata (Buenos Aires): Irrational and successful production model García, Matías El presente artículo da cuenta de los fundamentos, relaciones, lógicas y consecuencias que hacen posible el aparentemente exitoso modelo de la horticultura de La Plata (Buenos Aires). En este sentido, se describen los tres pilares que sostienen a la horticultura platense para luego detallar las consecuencias locales, regionales y aun nacionales, analizando además su comportamiento de exacerbación cíclica. Con dichos elementos se discute la sustentabilidad, racionalidad y razonabilidad del modelo y de los sujetos que lo impulsan, para finalmente identificar el origen del problema de lo que sería la “tragedia” de la horticultura platense, justificándose así pensar alternativas.; This article reports on the fundamentals, relationships, logic and consequences that make possible the seemingly successful model of horticulture in La Plata. In this sense, the three pillars which support La Plata’s horticulture are described, and then detail the local, regional and even national consequences and analysis the cyclic exacerbation behavioral. These elements are used to discuss sustainability, rationality and reasonableness of the model and the subjects that drive, to finally identify the source of the problem of what would be the "tragedy" of horticulture from La Plata, thus justifying think discusses alternatives.

First Record of Paratenic Hosts of the Swimbladder Nematode Anguillicola crassus in North America

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First Record of Paratenic Hosts of the Swimbladder Nematode Anguillicola crassus in North America Li, Wenxiang; Arnott, Stephen A.; Jones, Katherine M. M.; Braicovich, Paola Elizabeth; De Buron, Isaure; Wang, Guitang; Marcogliese, David J. Anguillicola crassus is a non-native parasite of the American eel, Anguilla rostrata. Since being introduced into North America, the nematode has spread rapidly across the range of A. rostrata, but paratenic hosts, which may facilitate parasite dispersion, have yet to be identified in the region. We investigated infection of larval A. crassus in 261 fish specimens belonging to 23 species and 12 orders collected from estuarine habitats in South Carolina (salinities 0-9 ppt) and Nova Scotia (10-18 ppt). A total of 35 fish belonging to 5 species and 3 orders were infected with the third-stage larvae (L3) of A. crassus, providing the first record of paratenic hosts for the parasite in North America. In South Carolina, high prevalence and abundance of the worm were found in spot (Leiostomus xanthurus), silver perch (Bairdiella chrysoura), and highfin goby (Gobionellus oceanicus), and a high prevalence but lower abundance was found in mummichog (Fundulus heteroclitus). In Nova Scotia, 2 nematodes were found in a single specimen of tomcod (Microgadus tomcod). All of the infected species are associated with a benthic lifestyle, and some of them are known to move between estuaries along the coastline. Lower infection rates in Nova Scotia may be associated with lower water temperatures and/or higher salinity of the sampling site. Most of the L3 were found encapsulated in mesenteric tissue around the intestine and stomach. No L4 or pre-adult worms were found. Mean body length of the L3 was smaller than L3 stages found in American eels from Cape Breton. This suggests that development of A. crassus is arrested at the L3 in the 5 fish species reported here, supporting their status as paratenic hosts.

Nonlinear electrodynamics as a symmetric hyperbolic system

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Nonlinear electrodynamics as a symmetric hyperbolic system Abalos, Julio Fernando; Carrasco, Federico León; Goulart, Érico; Reula, Oscar Alejandro Nonlinear theories generalizing Maxwell's electromagnetism and arising from a Lagrangian formalism have dispersion relations in which propagation planes factor into null planes corresponding to two effective metrics which depend on the pointwise values of the electromagnetic field. These effective Lorentzian metrics share the null (generically two) directions of the electromagnetic field. We show that the theory is symmetric hyperbolic if and only if the cones these metrics give rise to have a nonempty intersection, namely, that there exist families of symmetrizers in the sense of Geroch [26] which are positive definite for all covectors in the interior of the cones intersection. Thus, for these theories, the initial value problem is well posed. We illustrate the power of this approach with several nonlinear models of physical interest such as Born-Infeld, Gauss-Bonnet, and Euler-Heisenberg.

Matching in vitro bioaccessibility of polyphenols and antioxidant capacity of soluble coffee by Boosted Regression Trees

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Matching in vitro bioaccessibility of polyphenols and antioxidant capacity of soluble coffee by Boosted Regression Trees Podio, Natalia Soledad; López Froilán, Rebeca; Ramirez Moreno, Esther; Bertrand, Lidwina; Baroni, María Verónica; Pérez Rodríguez, María L.; Sánchez Mata, María Cortes; Wunderlin, Daniel A. The aim of this study was to evaluate changes in polyphenol profile and antioxidant capacity of five soluble coffees throughout a simulated gastro-intestinal digestion, including absorption through a dialysis membrane. Our results demonstrate that both polyphenol content and antioxidant capacity were characteristic for each type of studied coffee, showing a drop after dialysis. Twenty-seven compounds were identified in coffee by HPLC-MS, while only 14 of them were found after dialysis. Green+roasted coffee blend and chicory+coffee blend showed the highest and lowest content of polyphenols and antioxidant capacity before in vitro digestion and after dialysis, respectively. Canonical correlation analysis showed significant correlation between the antioxidant capacity and the polyphenol profile before digestion and after dialysis. Furthermore, boosted regression trees analysis (BRT) showed that only four polyphenol compounds (5-p-coumaroylquinic acid, quinic acid, coumaroyl tryptophan conjugated, and 5-O-caffeoylquinic acid) appear to be the most relevant to explain the antioxidant capacity after dialysis, these compounds being the most bioaccessible after dialysis. To our knowledge, this is the first report matching the antioxidant capacity of foods with the polyphenol profile by BRT, which opens an interesting method of analysis for future reports on the antioxidant capacity of foods.

La palomita escamada (columbina squammata) ocupa pequeños claros de desmontes en el Chaco húmedo

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La palomita escamada (columbina squammata) ocupa pequeños claros de desmontes en el Chaco húmedo Gandoy, Facundo Ariel; Brissón Egli, Federico; Gorleri, Fabricio Carlos; Castillo, Leandro; Zalazar, Sofia La Palomita Escamada (Columbina squammata) es un columbiforme que se distribuye únicamente en Sudamérica y posee dos subespecies alopátricas: C. s. ridgwayi al norte del subcontinente, y C. s. squammata en el sudeste de Brasil, Paraguay, este de Bolivia y norte de Argentina (Estela et al. 2005, Rodríguez-Mata et al. 2006). En este último país se la ha reportado solo en la provincia de Misiones (Partridge 1961, Narosky & Yzurieta 2003, Rodríguez-Mata et al. 2006, Krauczuk 2008, Bodrati et al. 2010). A continuación presentamos nuevos registros que expanden la distribución conocida a las provincias de Formosa, Corrientes y Chaco.

Multiclass compatible sample preparation for UHPLC-MS/MS determination of aflatoxin M1 in raw milk

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Multiclass compatible sample preparation for UHPLC-MS/MS determination of aflatoxin M1 in raw milk Michlig, Nicolás; Repetti, María Rosa; Chiericatti, Carolina; García, Silvia R.; Gaggiotti, Mónica; Basilico, Juan Carlos; Beldomenico, Horacio Ramon A sample preparation method for aflatoxin M1 (AFM1) determination in raw milk was optimized following the quick, easy, cheap, effective, rugged and safe (QuEChERS) strategy, as an alternative to the classic immunoaffinity column clean-up (IAC). The method was adapted to address the complexity of the milk matrix, and to be suitable for final determination by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS). This approach proved also to be compatible with the simultaneous extraction of pesticide residues and other contaminants (mycotoxins). Regarding AFM1, satisfactory linearity was achieved and appropriate sensitivity was maintained, using matrix-matched calibration to compensate for the heavy ion suppression. The accuracy and precision, which were determined through recovery studies, were 70–95 %, with the relative standard deviation below 15 % in all of the cases. The limit of detection (LOD, 0.002 μg L−1) and limit of quantification (0.007 μg L−1) are compatible with current worldwide regulations (maximum levels of 0.5 and 0.05 μg L−1). The procedure was applied to samples that were naturally contaminated with a range of AFM1 at LOQ–0.187 μg L−1, with comparable results to IAC clean-up, which was employed as a reference method. Therefore, AFM1 determination in raw milk by UHPLC–MS/MS detection through the present QuEChERS extraction constitutes a reliable alternative to IAC clean-up and exhibits advantages related to cost, accessibility of materials and simplicity of operation.

An improvement of the sensitivity of GPS radio occultation data to detect gravity waves through observational and modeling factors

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An improvement of the sensitivity of GPS radio occultation data to detect gravity waves through observational and modeling factors Alexander, Pedro Manfredo; de la Torre, Alejandro; Hierro, Rodrigo Federico; Llamedo Soria, Pablo Martin There is a mid-latitude region to the East of the Andes Range in the Southern Hemisphere that exhibits ideal conditions for the generation of gravity waves (GW) by topography mainly during winter. The configuration favors the generation of wavefronts that are parallel to the North–South direction. Global Positioning System (GPS) radio occultation (RO) retrievals from the COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) mission exhibit in a large proportion of the soundings an orientation which should be favorable to the detection of these wavefronts. We try to verify if this GW activity surplus on the East with respect to the West in the studied zone in winter emerges clearly in the GPS RO data between years 2007 and 2012. We argue that the orientation of the soundings but also the mathematical model selected to represent the GW energy distribution can affect the possibility of detecting the signatures of the waves. In particular, we explore a new interpretation of the GW energy distribution observed by GPS RO at the lowest values, as they stay below the precision limit of the technique. We suggest to replace that part of the measured distribution by an exponential curve that in general suits the trend of all the other observed energies. In following this alternative it is shown that the calculated mountain wave activity in the studied sector is now even more clearly larger in the East than in the West during winter. Finally, we consider that energy distributions observed with any measurement technique should in general not be considered as the solely contribution from waves, as also other variable phenomena may be adding to the final outcome.

Compromiso conductual y desafección con las actividades escolares: Explorando un modelo de facilitadores motivacionales y resultados de rendimiento

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Compromiso conductual y desafección con las actividades escolares: Explorando un modelo de facilitadores motivacionales y resultados de rendimiento; Behavioral engagement and disaffection in school activities: Exploring a model of motivational facilitators and performance outcomes González, Antonio; Paoloni, Paola Veronica Rita; Donolo, Danilo Silvio; Rinaudo, María Cristina Investigaciones previas han mostrado que el control percibido, el valor de la tarea, el compromiso conductual y la desafección son determinantes personales del rendimiento académico. Sin embargo, pocas investigaciones han examinado simultáneamente estos constructos en educación secundaria. El presente estudio analizó las relaciones estructurales entre estas variables y el papel del compromiso y la desafección como mediadores de los efectos del control y el valor sobre el rendimiento. Los participantes fueron 446 estudiantes (51.3% chicas) con edades comprendidas entre 12 y 16 años que asistían a seis colegios de educación secundaria obligatoria (de 7º a 10º cursos; de 1º a 4º de ESO). Las variables se evaluaron a lo largo de nueve meses. Los resultados de los modelos de ecuaciones estructurales confirmaron las hipótesis: el control y el valor predijeron significativamente el compromiso, la desafección y el rendimiento; el compromiso y la desafección predijeron el rendimiento y mediaron parcialmente los efectos del control y el valor sobre el rendimiento. Se concluye discutiendo las implicaciones para la teoría y la práctica psicoeducativa.; Previous research has shown that perceived control, task value, behavioral engagement and disaffection are personal determinants of academic performance. However, little research has simultaneously examined these constructs in secondary education. The present study analyzed the structural relationships between these variables and the role of engagement and disaffection as mediators of control and value on performance. Participants were 446 students (51.3% girls) ranging in age from 12 to 16 years attending six Spanish compulsory secondary schools (from 7th to 10th grades). The variables were assessed over a nine-month period. Structural equation models results confirmed the hypotheses: control and value significantly predicted engagement, disaffection, and performance; engagement and disaffection predicted performance and partially mediated the effects from control and value on performance. Implications for psycho-educational theory and practice are discussed.

Carcinoma neuroendocrino de timo con enfermedad de pompe del adulto

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Carcinoma neuroendocrino de timo con enfermedad de pompe del adulto; Thymic neuroendocrine carcinoma with Pompe's disease of the adult Aruj, Patricia K.; Rausch, Silvia; de Vito, Eduardo La enfermedad de Pompe (glucogenosis tipo II) es una enfermedad de depósito lisosomal, autosómica recesiva causada por una deficiencia de ácido alfa-glucosidasa. Los tumores neuroendocrinos tímicos son neoplasias primarias con diferenciación neuroendocrina que generalmente se presentan como una masa en el mediastino anterior. Ambas enfermedades se consideran raras en sí mismas. En nuestro conocimiento, la enfermedad de Pompe y un tumor neuroendocrino del timo en el mismo paciente no ha sido antes comunicada. No pudimos encontrar la plausibilidad biológica entre ambas enfermedades. Se necesitan más estudios para confirmar el hallazgo y para aumentar aún más nuestra comprensión de esta asociación. Los datos clínicos de los estudios epidemiológicos, los informes de casos, las series de casos y los pequeños ensayos clínicos abiertos o controlados pueden definir tanto la plausibilidad clínica como la causalidad entre las dos enfermedades.; Pompe disease (glycogenosis type II) is an inherited autosomal recessive lysosomal storage disease caused by a deficiency of acid alpha-glucosidase. Thymic neuroendocrine tumors, are primary thymic neoplasms with neuroendocrine differentiation that generally present as a mass within the anterior mediastinum. Both diseases are considered rare. To our knowledge the co-existence of Pompe disease and thymic neuroendocrine tumor in the same patient has not been previously reported. We could not find biological plausibility between both diseases. Further studies are needed to confirm the finding and to further increase our understanding of this association. Clinical data from epidemiological studies, case reports, case series and small formal open or controlled clinical trials may define both clinical plausibility and causality between the two conditions.

Hypoxia-induced nitric oxide release by luminal cells stimulates proliferation and uPA secretion of myoepithelial cells in a bicellular murine mammary tumor

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Hypoxia-induced nitric oxide release by luminal cells stimulates proliferation and uPA secretion of myoepithelial cells in a bicellular murine mammary tumor Krasnapolski, Martin Alejandro; Lodillinsky, Catalina; Bal, Elisa Dora; Eijan, Ana Maria Introduction: LM38 murine mammary adenocarcinoma model is formed by LM38-LP (myoepithelial and luminal), LM38-HP (luminal) and LM38-D2 (myoepithelial) cell lines. In a previous work, we had shown that LM38-HP and LM38-D2 cell lines are less malignant than the bicellular LM38-LP cell line. Purpose: To study the role of nitric oxide (NO) as one of the mediators of functional interactions between malignant luminal and myoepithelial cells. Methods and results: Using immunohistochemistry, in vivo iNOS expression was only detected in the luminal cells of bicellular LM38-LP and most cells of LM38-HP tumors. In cobalt-induced pseudohypoxia, LM38-LP and LM38-HP cell lines significantly increased HIF-1α and iNOS expression (Western blotting) and therefore NO production (Griess method). This increase was inhibited by the iNOS inhibitor 1400 W. On the other side, NO was not detectable in LM38-D2 cells either in basal or in pseudohypoxia. In addition, pseudohypoxia increased urokinase-type plasminogen activator (uPA) secretion by LM38-LP and LM38-HP cells and migration in the LM38-LP cell line, without modulating these properties in LM38-D2 cells (radial caseinolysis). The NO donor DETA/NONOate (500 μM) was able to increase uPA secretion and in vitro growth of LM38-D2. In agreement, 1400 W prevented in vivo growth of the myoepithelial LM38-D2 cells. Conclusions: Hypoxia leads to an enhanced NO production by the luminal component, through HIF-1α and iNOS, which can stimulate myoepithelial cell proliferation and uPA secretion. In these new conditions, myoepithelial cells might act as an invasive forefront generating gaps that could help luminal cells to escape from the primary tumor.

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