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Trophic ecology of the yellowfin notothen, Patagonotothen guntheri (Norman, 1937) at the Marine Protected Area Namuncurá-Burdwood Bank, Argentina

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Trophic ecology of the yellowfin notothen, Patagonotothen guntheri (Norman, 1937) at the Marine Protected Area Namuncurá-Burdwood Bank, Argentina Covatti Ale, Marina; Fischer, Luciana Stefania; Deli Antoni, Mariana Yanel; Díaz de Astarloa, Juan Martín; Delpiani, Gabriela Elina The yellowfin notothen Patagonotothen guntheri is an important fish species in the Marine Protected Area Namuncurá-Burdwood Bank (MPAN-BB) due to its high abundance and significant ecological role. Thus, diet composition and feeding habits were analyzed. To fulfill this purpose, percentage frequency of occurrence, prey-specific abundance, and prey-specific index of relative importance (%PSIRI) were calculated. Generalized linear models were built for the defined prey categories to assess changes in feeding associated with total length, sex, depth, and zone of capture. Two hundred fifty-two specimens were sampled (69–256 mm total length), of which 186 contained food (73.41%). According to PSIRI, ophiuroids (23.28%), unidentified polychaetes (17.92%), and Munida gregaria (12.73%) were the main prey items. However, yellowfin notothen showed variations in diet composition according to their length and the depth of capture. The consumption of decapods and other invertebrates increased with depth, while the ingestion of ophiuroids decreased. Also, the number of polychaetes was higher in the stomach content of larger specimens. The present work provides the first description and analysis of P. guntheri trophic ecology in the MPAN-BB, concluding that it is a species with a generalist diet, which feeds on a great diversity of both benthic and pelagic organisms depending on availability.

Persian Walnut (Juglans regia L.) Bud Dormancy Dynamics in Northern Patagonia, Argentina

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Persian Walnut (Juglans regia L.) Bud Dormancy Dynamics in Northern Patagonia, Argentina del Barrio, Ricardo Alfredo; Orioli, Gustavo Adolfo; Brendel, Andrea Soledad; Lindström, Lilia Ivone; Pellegrini, Cecilia; Campoy, José Antonio Temperate deciduous fruit trees survive winter temperatures by entering a dormant phase in their aerial meristematic organs. Release from bud dormancy occurs after chill requirements (CR) have been satisfied, whereas bud burst/flowering follows heat requirement (HR) fulfillment. The physiological basis behind these metrics remains elusive. In this study, we are presenting the first multidisciplinary dormancy progression analysis in northern Patagonia, linking (1) forcing/field phenology, (2) bud anatomical development, and (3) soluble sugar (sucrose, glucose, and fructose) dynamics in Juglans regia L. CR and HR were determined for ‘Chandler’ and ‘Franquette,’ two walnut cultivars with markedly different CR, in artificial chill/forced heat trials (three seasons) and in-field chill/forced heat tests (five seasons) using excised twigs either with or without apical buds (non-decapitated and decapitated). The soluble sugar dynamics of ‘Chandler’ (high-performance liquid chromatography) and the anatomical changes of the buds (light microscopy) of the two cultivars were analyzed during endo-ecodormancy progression in one and two seasons, respectively. The CR defined by artificial chill tests proved to be an overestimation compared to the field determinations. Moreover, HR was the main driver in the phenology dynamics, as expected for a high-chill region. ‘Chandler’ showed an average of 10.3 field chill portions (CP) and 2,163 Growing Degree Hours (GDH°C) less than ‘Franquette’ for dormancy release and bud burst, respectively. These results were consistent with the transition of the shoot apex from the vegetative to the reproductive phase and the soluble sugar profile. The decrease in sucrose between 15 and 30 days after CR fulfillment could be a reliable biological marker for endodormancy release in walnut, while the increase in fructose and glucose is likely an osmolyte and cellulosic carbon source in pre-sprouting. In addition, we discuss the effect of paradormancy thanks to our apical bud experiment (with or without). Our results improve the current understanding of endo-ecodormancy progression in walnut and provide insightful results for walnut production (i.e., cultivation practices such as pruning) as well as for further application in dormancy modeling, to infer the ideotypes that should be bred for future climate conditions.

Consumo de información en redes sociales en tiempos de pandemia: Evidencias del caso argentino

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Consumo de información en redes sociales en tiempos de pandemia: Evidencias del caso argentino; Information consumption on social networks in times of a pandemic: Evidence from the Argentine case; Consumo de informações nas redes sociais em tempos de pandemia: Provas do caso argentino Zunino, Esteban; Kessler, Gabriel; Vommaro, Gabriel Alejandro Este artículo estudia los contenidos de la información más consumida por parte de las/los usuarios/as de Facebook en Argentina, en el contexto de la pandemia por COVID-19. Se indagan: 1) los asuntos que mayor nivel de involucramiento generaron en esa red social; 2) la procedencia de las piezas informativas más relevantes; y 3) el tipo de encuadres que predominaron en el tratamiento de los diferentes problemas. Mostramos, primero, que el COVID-19 adquirió mayor relevancia que el resto de los asuntos en Facebook, aunque el nivel de involucramiento de las/ los usuarios/as sobre el tema se relacionó con la ocurrencia de diferentes eventos críticos asociados a la pandemia. Segundo, que las noticias más relevantes provinieron de medios de comunicación con marcas consolidadas, por lo que la lectura de información en la red social estuvo concentrada. Por último, que la proximidad geográfica, el conflicto, el interés humano y los rasgos afectivos explícitos en los posteos informativos constituyen rasgos de la información que explican su relevancia en la red social. El estudio consiste en un análisis de los contenidos informativos que mayor nivel de involucramiento alcanzaron (likes, comments y shares) en Facebook entre enero de 2020 y junio de 2021.; Este artigo estuda o conteúdo das informações mais consumidas pelos usuários do Facebook na Argentina, no contexto da pandemia de COVID-19. São investigados: 1) as questões que geraram o maior grau de envolvimento naquela rede social; 2) a origem das informações mais relevantes; e 3) o tipo de ambiente que predominou no tratamento dos diferentes problemas. Mostramos, em primeiro lugar, que o COVID-19 adquiriu maior relevância do que os demais problemas do Facebook, embora o nível de envolvimento dos usuários sobre o assunto estivesse relacionado à ocorrência de diversos eventos críticos associados à pandemia. Em segundo lugar, que as notícias mais relevantes vieram da mídia com marcas consolidadas, então concentrouse a leitura de informações na rede social. Por fim, que proximidade geográfica, conflito, interesse humano e traços afetivos explícitos nas postagens de notícias constituem características da informação que explicam sua relevância na rede social. O estudo consiste na análise do conteúdo informativo que atingiu o maior nível de engajamento no Facebook entre janeiro de 2020 e junho de 2021.; This article studies the contents of the most consumed information by Facebook users in Argentina, in the context of the COVID-19 pandemic. We investigate: 1) the issues that generated the highest level of engagement in this social media; 2) the origin of the most relevant pieces of information; and 3) the type of framing that predominated in the treatment of topics associated with the pandemic. We show, first, that COVID-19 acquired greater relevance than the other issues on Facebook, although the level of engagement of users on the subject was related to several critical events associated with the pandemic. Second, the most releant news came from media outlets with consolidated brands, so that news consumption on the social media was concentrated. Finally, geographic proximity, conflict, human interest and explicit affective features in the posts are features of the news that explain its relevance in the social media. The study consists in analyzing the news content that achieved the highest level of engagement (likes, comments and shares) on Facebook between January 2020 and June 2021.

La ciencia jurídica en la enseñanza del derecho

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La ciencia jurídica en la enseñanza del derecho Richter, Anna Erna Marianne Una de las preguntas más desconcertantes que se nos puede hacer a quienes investigamos y escribimos sobre el derecho es la pregunta por la utilidad de la ciencia jurídica. Más allá del disfrute personal de obtener conocimiento y agrandar las bibliotecas jurídicas con artículos que llevan nuestros nombres, ¿cuál es el aporte que brinda esta tarea a la comunidad jurídica y a toda la sociedad? En este trabajo intentaré argumentar que lacienciajurídica, y con ello la dogmática penal, no solo brinda un servicio importante a la sociedad, sino también que esa tarea requiere de un tipo de enseñanza jurídica específica, que se podría llamar el método de casos. Para ello presentaré primero algunas observaciones sobre las posibles tareas de la ciencia jurídica y, segundo, analizaré qué tipo de formación se requiere para realizar tales tareas. En un tercer punto me ocuparé de algunos desafíos pendientes respecto de la investigación y enseñanza jurídica que todavía no parecen recibir la atención que merecen.; One of the most perplexing questions that can be asked of those of us who research and write about the law is the question of the usefulness of legal scholarship. Beyond the personal pleasure of gaining knowledge and adding to law libraries with articles bearing our names, what contribution does it make to the legal profession and to society as a whole? In this paper I will try to argue that legal scholarship, and with it criminal law theory, not only provides an important service to society, but also that this task requires a particular kind of legal teaching, which could be called the case method. To this end, I will first make some remarks about the possible tasks of legal scholarship, and secondly, I will analyse what kind of training is required to carry out such tasks. Thirdly, I will address some outstanding challenges to legal research and teaching that still do not seem to receive the attention they deserve.

Binding of the angiogenic/senescence inducer CCN1/CYR61 to integrin α6β1 drives endocrine resistance in breast cancer cells

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Binding of the angiogenic/senescence inducer CCN1/CYR61 to integrin α6β1 drives endocrine resistance in breast cancer cells Espinoza, Ingrid; Yang, Lin; Steen, Travis Vander; Vellón, Luciano; Cuyàs, Elisabet; Verdura, Sara; Lau, Lester; Menendez, Javier A.; Lupu, Ruth CCN1/CYR61 promotes angiogenesis, tumor growth and chemoresistance by binding to its integrin receptor αvβ3 in endothelial and breast cancer (BC) cells. CCN1 controls also tissue regeneration by engaging its integrin receptorα6β1 to induce fibroblast senescence. Here, we explored if the ability of CCN1 to drive an endocrine resistancephenotype in estrogen receptor-positive BC cells relies on interactions with either αvβ3 or α6β1. First, we tookadvantage of site-specific mutagenesis abolishing the CCN1 receptor-binding sites to αvβ3 and α6β1 to determine theintegrin partner responsible for CCN1-driven endocrine resistance. Second, we explored a putative nuclear role ofCCN1 in regulating ERα-driven transcriptional responses. Retroviral forced expression of a CCN1 derivative with asingle amino acid change (D125A) that abrogates binding to αvβ3 partially phenocopied the endocrine resistancephenotype induced upon overexpression of wild-type (WT) CCN1. Forced expression of the CCN1 mutant TM,which abrogates all the T1, H1, and H2 binding sites to α6β1, failed to bypass the estrogen requirement foranchorage-independent growth or to promote resistance to tamoxifen. Wild-type CCN1 promoted estradiol-independent transcriptional activity of ERα and enhanced ERα agonist response to tamoxifen. The α6β1-binding-defective TM-CCN1 mutant lost the ERα co-activator-like behavior of WT-CCN1. Co-immunoprecipitation assaysrevealed a direct interaction between endogenous CCN1 and ERα, and in vitro approaches confirmed the ability ofrecombinant CCN1 to bind ERα. CCN1 signaling via α6β1, but not via αvβ3, drives an endocrine resistance phenotypethat involves a direct binding of CCN1 to ERα to regulate itstranscriptional activity in ER+ BC cells.

Broadly neutralizing antibodies overcome SARS-CoV-2 Omicron antigenic shift

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Broadly neutralizing antibodies overcome SARS-CoV-2 Omicron antigenic shift Cameroni, Elisabetta; Bowen, John E.; Rosen, Laura E.; Saliba, Christian; Zepeda, Samantha K.; Culap, Katja; Pinto, Dora; VanBlargan, Laura A.; De Marco, Anna; di Iulio, Julia; Zatta, Fabrizia; Kaiser, Hannah; Noack, Julia; Farhat, Nisar; Czudnochowski, Nadine; Havenar Daughton, Colin; Sprouse, Kaitlin R.; Dillen, Josh R.; Powell, Abigail E.; Chen, Alex; Maher, Cyrus; Yin, Li; Sun, David; Soriaga, Leah; Bassi, Jessica; Silacci Fregni, Chiara; Gustafsson, Claes; Franko, Nicholas M.; Logue, Jenni; Geffner, Jorge Raúl The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593 and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.

Feeding strategies and ageing time alter calpain system proteins activities and meat quality of Braford steers

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Feeding strategies and ageing time alter calpain system proteins activities and meat quality of Braford steers Coria, Maria Sumampa; Pighín, Darío Gabriel; Grigioni, Gabriela Maria; Palma, Gustavo Adolfo Objective: The aim of this study was to evaluate the effect of ageing and feeding strategies on the calpain protease system and meat quality traits in Braford steers. Methods: Thirty Braford steers were employed; 15 animals were supplemented with corn silage during finishing and 15 were kept only on pasture. Meat quality traits and calpain system protein activity were evaluated in longissimus thoracis et lumborum (LTL) steaks aged for 2, 7, 14, and 21 days. Results: Aged meat showed higher pH and calcium content, while Warner Bratzler shear force (WBSF) decreased to day 21. No interaction between ageing and diet was seen for quality traits. Steers finished with corn silage showed higher values of water holding capacity, WBSF and free calcium, and lower values of pH and cooking loss. Calpain and calpastatin activities decreased with ageing. Finishing steers on pasture produced higher values of calpains and lower values of calpastatin activities. The higher values of calpain 1 activity were observed in muscles aged 2 days from pasture finished animals, and the lower activity of the inhibitor in the 21 days aged samples of the same group. Conclusion: These results suggest a diet by ageing interaction in calpains and calpastatin and this interaction impact in Warner Bratzler Shear Force in Braford LTL muscle.

Evaluación de Arundo Donax L. como biocombustible para la producción de energía térmica

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Evaluación de Arundo Donax L. como biocombustible para la producción de energía térmica; Evaluation of Arundo Donax L. as a biofuel for thermal energy production Pereyra Müller, Nahuel; Manzur, Alejandra Marisa; Santalla, Estela Mercedes; Córdoba, Verónica Elizabeth Se estudió el comportamiento de Arundo donax L., cultivo perenne conocido como caña de Castilla, que puede crecer en una amplia variedad de suelos, como potencial biocombustible para uso directo como fuente de energía térmica. Se determinó contenido de humedad, cenizas, sólidos volátiles, composición química y elemental y poder calorífico utilizando técnicas estándares sobre muestras de fardos de biomasa. Se evaluó el comportamiento térmico a partir de la combustión directa en equipo convencional de uso doméstico. Se analizó la eficiencia del proceso a partir de la prueba de ebullición del agua y se midieron las emisiones gaseosas en forma comparativa con otras biomasas convencionales. Los resultados del estudio indicaron que Arundo donax L. presenta un poder calorífico superior de 19,1 MJ/kg y una composición elemental con más de 45% de carbono. El test de ebullición de agua mostró para esta biomasa el menor tiempo (28 min) y consumo de combustible (1119 g/L) y la mayor velocidad de combustión (90,2 g/min) respecto a otras biomasas convencionales, mientras que el perfil de gases de combustión reveló emisiones de CO2 similares a pellets y leña (2,2%), porcentaje de CO inferior a marlos, aunque algo inestable en el tiempo y baja emisión de NOx (22,5 ppm).; The behavior of Arundo donax L., a perennial crop known as Caña de Castilla, which can grow in a wide variety of soils, was studied as a potential biofuel for direct use as a source of thermal energy. Moisture content, ash, volatile solids, chemical and elemental composition and calorific value were determined using standard techniques on samples of biomass bales. The thermal behavior was evaluated from direct combustion in conventional equipment for domestic use. The efficiency of the process was evaluated from the Water Boiling Test and the gaseous emissions from combustion were measured in comparison with other conventional biomass. The results of the study indicated that Arundo donax L. has a higher calorific value of 19.1 MJ/kg and an elemental composition with more than 45% carbon. The Water Boiling Test showed the shortest time (28 min) and fuel consumption (1119 g / L) and the highest combustion rate (90.2 g/min) compared to other conventional biomass, while the combustion gas profile showed CO2 emissions similar to pellets and firewood (2.2%), lower percentage of CO than marlos, although somewhat unstable over time, and low NOx emissions (22.5 ppm).

Defining multiple inhabitations of a cave environment using interdisciplinary archaeometry: the ‘Christmas Cave’ of the Wadi en-Nar/Nahal Qidron, West of the Dead Sea

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Defining multiple inhabitations of a cave environment using interdisciplinary archaeometry: the ‘Christmas Cave’ of the Wadi en-Nar/Nahal Qidron, West of the Dead Sea Rasmussen, Kaare Lund; van der Plicht, Johannes; Degano, Ilaria; Modugno, Francesca; Colombini, Maria Perla; de la Fuente, Guillermo Adrian; Delbey, Thomas; Frumkin, Amos; Davidovich, Uri; Porat, Roi; Shamir, Orit; Sukenik, Naama; Doudna, Greg; Taylor, Joan; Popović, Mladen The present study reports a series of interdisciplinary archaeometrical analyses of objects found in the Christmas Cave, which was discovered by John Allegro and his team in 1960 on the West Bank of the Dead Sea and assumed to be inhabited only in the Chalcolithic era and by Jewish refugees of the second century CE, at the end of the Bar Kokhba Revolt. Like many other Judaean desert caves, there was an abundance of organic material, especially textiles, surviving in the dry environment. In the absence of clear stratigraphy and even a proper publication of the finds, the present study shows how archaeometry can provide important insights. We analysed food crusts on ceramics by gas chromatography with mass spectrometric detection (GC–MS), made petrographic descriptions to estimated provenance of the ceramics, produced new radiocarbon dates from organic material and thermoluminescence (TL) dates from the pottery. It appears from the data that the Christmas Cave has been briefly inhabited or visited intermittently over a very long time, starting ca. 4000 BCE (the Chalcolithic period), and extending all the way to the Medieval period, even though there is also a concentration of dates near the period of the Bar Kokhba Revolt (132–136 CE). We argue, through a detailed analysis of the radiometric and TL-datings and by the artefactual evidence, that there was likely another refuge episode connected with the First Jewish Revolt during which people fled to this cave. However, we see no material connection to Qumran and nearby caves. Overall, our study demonstrates the importance of archaeometric studies in cave environments where stratigraphy is veritably absent.

In silico Analysis of the Entire P. glaucum Genome Identifies Regulatory Genes of the bZIP Family Modulated in Response Pathways to Water Stress

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In silico Analysis of the Entire P. glaucum Genome Identifies Regulatory Genes of the bZIP Family Modulated in Response Pathways to Water Stress Garay Farías, Laura Beatriz; Litwiñiuk, Sergio Leandro; Rojas, Cristian Antonio The literature reviewed places P. glaucum as a cereal characterized by its nutritional quality and high tolerance to drought stress. However, very little is known about the fine mechanism it uses in response to water stress. To try to clarify this point, we carried out an analysis of the modulation of the expression of regulatory genes of the FT bZIP family. A full genome screening of P. glaucum identified 52 putative FT bZIPs, identifying 9 FT PgbZIP differentially expressed under water stress conditions filtered from RNA-seq data from a Transcriptome deposited at the NCBI. The promoter regions of these genes presented multiple elements or cis ABREs and DRE motifs, thus suggesting their double modulated participation in the slow or adaptive response and in the rapid response of this cereal to water stress. The findings of this study provide complementary data for the understanding of the mechanism behind the adaptation of P. glaucum under water stress, and may be relevant for molecular applications of potential crops.

Consumers’ Opinion and Perception toward a Convenience Food through Projective Techniques

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Consumers’ Opinion and Perception toward a Convenience Food through Projective Techniques Abalos, Rosa Ana; Naef, Elisa Fernanda; Aviles, Maria Victoria; Gómez, María Beatriz Convenience food cooked by sous vide has been developing in the field of high cuisine and restaurants. In this paper the perception of Argentinian consumers of a convenience food cooked by sous vide was explored through the use of projective techniques. The results demonstrated that good taste and convenience were the principal positive characteristics that promoted the intent to purchase a convenience food cooked by sous vide, whereas mistrust and lack of knowledge of the preparation and composition of the product discouraged the consumption.

El derecho a la educación en Argentina en tiempos de virtualidad forzada: Un supuesto de judicialización de la inclusión digital

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El derecho a la educación en Argentina en tiempos de virtualidad forzada: Un supuesto de judicialización de la inclusión digital; The right to education in argentina in times of forced virtuality: A case of judicialization of digital inclusion Torres, Miguel Agustín; Ibañez, Cecilia Elizabeth Como es sabido, la instalación de la pandemia implicó en muchos escenarios la imposición de restricciones a la movilidad y al desempeño, en condiciones de normalidad, con respecto a determinadas actividades. La sociedad argentina no fue ajena a este proceso, el cual, en materia de educación, se tradujo en la suspensión de la presencialidad de las clases áulicas, y por consiguiente, en la implementación forzada, de un trayecto de enseñanza y aprendizaje de naturaleza remota. Teniendo en cuenta ellos, en este trabajo nos proponemos caracterizar, desde una perspectiva jurídica, el acceso a los medios y recursos digitales, en tanto manifestación del derecho a la educación, en el marco del complejo contexto impuesto por la pandemia. Para ello procedemos a analizar un fallo relevante en la materia correspondiente al ámbito judicial del principal distrito del país.; As is known, the installation of the pandemic implied in many scenarios the imposition of restrictions on mobility and performance, under normal conditions, with respect to certain activities. Argentine society was not aloof to this process, which, in terms of education, resulted in the suspension of face-to-face classes, and therefore, in the forced implementation of a remote teaching and learning process. Considering this, in this work we propose to characterize, from a legal perspective, access to digital media and resources, as a manifestation of the right to education, within the framework of the harsh context generated by the pandemic. For this, we proceed to analyze a relevant ruling in the matter corresponding to the judicial sphere of the main district of the country.

Enhanced Thermal Stability in Dielectric Properties of NaNbO3 –Modified BaTiO3 –BiMg1/2 Ti1/2 O3 Ceramics for X9R-MLCC Applications

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Enhanced Thermal Stability in Dielectric Properties of NaNbO3 –Modified BaTiO3 –BiMg1/2 Ti1/2 O3 Ceramics for X9R-MLCC Applications Muhammad, Raz; Ali, Asif; Camargo, Javier Eduardo; Castro, Miriam Susana; Lei, Wen; Song, Kaixin; Wang, Dawei 0.5BaTiO3 –(0.5 − x)BiMg1/2 Ti1/2 O3 –xNaNbO3 (x = 0.10–0.30) ceramics were processed via a conventional solid state sintering route. X-ray diffraction analysis and Raman spectroscopy showed the formation of a cubic perovskite structure. Microstructural analysis of the samples revealed densely packed grains. The addition of NaNbO3 resulted in the enhancement in dielectric properties as a function of temperature. Relative permittivity decreased from 850 to 564 (at room temperature) with an increase in x; however, the stability in dielectric properties was improved with an increase in NaNbO3 concentration. At x = 0.25, relative permittivity (εr ) was ~630 ± 15% in a temperature range of −70–220◦ C with low dielectric loss (tan δ) < 0.025 (−57 to 350◦ C) and high recoverable energy density ~0.55 J/cm3 which meet the criterion for X9R MLCC applications.

Revisiting the influence of learning in predator functional response, how it can lead to shapes different from type III

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Revisiting the influence of learning in predator functional response, how it can lead to shapes different from type III Bruzzone, Octavio Augusto; Aguirre, María Belén; Hill, Jorge Guillermo; Virla, Eduardo Gabriel; Logarzo, Guillermo Alejandro Predator/parasitoid functional response is one of the main tools used to study predation behavior, and in assessing the potential of biological control candidates. It is generally accepted that predator learning in prey searching and manipulation can produce the appearance of a type III functional response. Holling proposed that in the presence of alternative prey, at some point the predator would shift the preferred prey, leading to the appearance of a sigmoid function that characterized that functional response. This is supported by the analogy between enzyme kinetics and functional response that Holling used as the basis for developing this theory. However, after several decades, sigmoidal functional responses appear in the absence of alternative prey in most of the biological taxa studied. Here, we propose modeling the effect of learning on the functional response by using the explicit incorporation of learning curves in the parameters of the Holling functional response, the attack rate (a), and the manipulation time (h). We then study how the variation in the parameters of the learning curves causes variations in the shape of the functional response curve. We found that the functional response product of learning can be either type I, II, or III, depending on what parameters act on the organism, and how much it can learn throughout the length of the study. Therefore, the presence of other types of curves should not be automatically associated with the absence of learning. These results are important from an ecological point of view because when type III functional response is associated with learning, it is generally accepted that it can operate as a stabilizing factor in population dynamics. Our results, to the contrary, suggest that depending on how it acts, it may even be destabilizing by generating the appearance of functional responses close to type I.

Opportunities and challenges for newborn screening and early diagnosis of rare diseases in Latin America

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Opportunities and challenges for newborn screening and early diagnosis of rare diseases in Latin America Giugliani, Roberto; Castillo Taucher, Silvia; Hafez, Sylvia; Oliveira, Joao Bosco; Rico-Restrepo, Mariana; Rozenfeld, Paula Adriana; Zarante, Ignacio; Gonzaga Jauregui, Claudia Rare diseases (RDs) cause considerable death and disability in Latin America. Still, there is no consensus on their definition across the region. Patients with RDs face a diagnostic odyssey to find a correct diagnosis, which may last many years and creates a burden for caregivers, healthcare systems, and society. These diagnostic delays have repercussions on the health and economic burden created by RDs and continue to represent an unmet medical need. This review analyzes barriers to the widespread adoption of newborn screening (NBS) programs and early diagnostic methods for RDs in Latin America and provides recommendations to achieve this critical objective. Increasing the adoption of NBS programs and promoting early diagnosis of RDs are the first steps to improving health outcomes for patients living with RDs. A coordinated, multistakeholder effort from leaders of patient organizations, government, industry, medical societies, academia, and healthcare services is required to increase the adoption of NBS programs. Patients’ best interests should remain the guiding principle for decisions regarding NBS implementation and early diagnosis for RDs.

Strongyloides stercoralis and Trypanosoma cruzi coinfections in a highly endemic area in Argentina

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Strongyloides stercoralis and Trypanosoma cruzi coinfections in a highly endemic area in Argentina Fleitas, Pedro Emanuel; Floridia Yapur, Noelia Aldana del Rosario; Nieves, Elvia Ester; Echazú, Adriana; Vargas, Paola Anahí; Caro, Reynaldo Nicolás; Aveldaño, Ramiro; Lopez, Walter; Fernandez, Mariana; Crudo, Favio; Cimino, Rubén Oscar; Krolewiecki, Alejandro Javier Background Strongyloidiasis and Chagas disease are endemic in northern Argentina. In this study we evaluate the association between S. stercoralis and T. cruzi infections in villages with diverse prevalence levels for these parasites. Further understanding in the relationship between these Neglected Tropical Diseases of South America is relevant for the design of integrated control measures as well as exploring potential biologic interactions. Methodology Community based cross-sectional studies were carried in different villages of the Chaco and Yungas regions in Argentina. Individuals were diagnosed by serology for S. stercoralis and T. cruzi. The association between S. stercoralis and T. cruzi, and between anemia and the two parasites was evaluated using two approaches: marginal (Ma) and multilevel regression (Mu). Results A total of 706 individuals from six villages of northern Argentina were included. A total of 37% were positive for S. stercoralis, 14% were positive for T. cruzi and 5% were positive for both. No association was found between infection with S. stercoralis and T. cruzi in any of the models, but we found a negative correlation between the prevalence of these species in the different villages (r =-0.91). Adults (> 15 years) presented association with S. stercoralis (Ma OR = 2.72; Mu OR = 2.84) and T. cruzi (Ma OR = 5.12; Mu OR = 5.48). Also, 12% and 2% of the variance of infection with S. stercoralis and T. cruzi, respectively, could be explained by differences among villages. On the other hand, anemia was associated with infection with S. stercoralis (Ma OR = 1.73; Mu OR = 1.78) and was more prevalent in adults (Ma OR = 2.59; Mu OR = 2.69). Conclusion We found that coinfection between S. stercoralis and T. cruzi is not more frequent than chance in endemic areas. However, the high prevalence for both parasites, raises the need for an integrated strategy for the control of STH and Chagas disease.

Hydrogeomorphological control over groundwater composition in littoral environments in the outer estuary of the Rio de la Plata

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Hydrogeomorphological control over groundwater composition in littoral environments in the outer estuary of the Rio de la Plata Tanjal, Carolina Verónica; Galliari, Maria Julieta; Borzi, Guido Esteban; Santucci, Lucía; Villalba, Esteban; Richiano, Sebastián Miguel; Carol, Eleonora Silvina The aim of this work is to determine the hydrochemical characteristics of groundwater in littoral ridges, sand sheets, and lunettes environments to evaluate the control that hydro-geomorphological features exert over salinity and water chemistry. To achieve this, geomorphological units were mapped and a groundwater monitoring network was established comprising shallow exploration wells and pre-existing deeper wells. Hydrolithological characteristics of sediments were described during field surveys, and also analyzed by XRD technique and binocular magnifying glass observation. Physicochemical parameters of water were measured in situ and samples were taken for major and trace elements (As, Sr, Fe, and Mn) analysis. Both littoral ridges and sand sheets are constituted by shell fragments and sands which are highly permeable sediments where thicker and freshwater lenses are stored. Conversely, lunettes develop smaller lenses due to the presence of silty sediments, which are shallow salinized. Additionally, water—sediment interaction determines geochemical processes like precipitation—dissolution of minerals (mainly carbonates), cation exchange, amorphous and biogenic silica dissolution, and silicate weathering which also regulate the presence of elements, such as As, Fe, and Mn. Given the relevance of littoral ridges, sand sheets, and lunettes in the development of freshwater lenses for water supply for the population and ecological sustenance, it is important to understand the factors and processes which regulate groundwater quality, primarily in sectors where freshwater sources are scarce.

On Tycho's Calculation of the Coordinates of Hamal, the Fundamental Star of Tycho's Catalog

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On Tycho's Calculation of the Coordinates of Hamal, the Fundamental Star of Tycho's Catalog Carman, Christian Carlos Tycho's star catalog enjoyed enormous prestige for centuries due to its accuracy. The entire catalog depends on the coordinates of one single star, Hamal (α Arietis), which explains why Tycho was so scrupulous in determining its coordinates using two different methods applied to more than 50 observations, as he described in his Progymnasmata. One of them proposed an ingenious way of dealing with refraction and parallax, two factors that he knew he could not control. Selecting particular observations, he was able to cancel out the effects of both refraction and parallax. Still, the entire calculation starts from the coordinates of the Sun calculated from his solar model. But Tycho's solar model assumes too large of an eccentricity, producing errors in the predictions of the solar longitude that can reach up to 8'. In this paper, I analyze Tycho's method for calculating the coordinates of α Arietis and explain how the method he proposed unintentionally avoided transferring the error of his solar model to his catalog.

Postharvest Ultraviolet Radiation in Fruit and Vegetables: Applications and Factors Modulating Its Efficacy on Bioactive Compounds and Microbial Growth

CONICET Digital -

Postharvest Ultraviolet Radiation in Fruit and Vegetables: Applications and Factors Modulating Its Efficacy on Bioactive Compounds and Microbial Growth Darré, Magalí; Vicente, Ariel Roberto; Cisneros Zevallos, Luis; Artés Hernández, Francisco Ultraviolet (UV) radiation has been considered a deleterious agent that living organisms must avoid. However, many of the acclimation changes elicited by UV induce a wide range of positive effects in plant physiology through the elicitation of secondary antioxidant metabolites and natural defenses. Therefore, this fact has changed the original UV conception as a germicide and potentially damaging agent, leading to the concept that it is worthy of application in harvested commodities to take advantage of its beneficial responses. Four decades have already passed since postharvest UV radiation applications began to be studied. During this time, UV treatments have been successfully evaluated for different purposes, including the selection of raw materials, the control of postharvest diseases and human pathogens, the elicitation of nutraceutical compounds, the modulation of ripening and senescence, and the induction of cross-stress tolerance. Besides the microbicide use of UV radiation, the effect that has received most attention is the elicitation of bioactive compounds as a defense mechanism. UV treatments have been shown to induce the accumulation of phytochemicals, including ascorbic acid, carotenoids, glucosinolates, and, more frequently, phenolic compounds. The nature and extent of this elicitation have been reported to depend on several factors, including the product type, maturity, cultivar, UV spectral region, dose, intensity, and radiation exposure pattern. Even though in recent years we have greatly increased our understanding of UV technology, some major issues still need to be addressed. These include defining the operational conditions to maximize UV radiation efficacy, reducing treatment times, and ensuring even radiation exposure, especially under realistic processing conditions. This will make UV treatments move beyond their status as an emerging technology and boost their adoption by industry.

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