113 research outputs found
One Week of Motor Adaptation Induces Structural Changes in Primary Motor Cortex That Predict Long-Term Memory One Year Later
The neural bases of motor adaptation have been extensively explored in human and non-human primates. A network including the cerebellum, primary motor and the posterior parietal cortex appears to be crucial for this type of learning. Yet, to date, it is unclear whether these regions contribute directly or indirectly to the formation of motor memories. Here we trained subjects on a complex visuomotor rotation associated with long-term memory (in the order of months) to identify potential sites of structural plasticity induced by adaptation. One week of training led to i) an increment in local gray-matter concentration over the hand area of the contralateral primary motor cortex and ii) an increase in fractional anisotropy in an area underneath this region that correlated with the speed of learning. Moreover, the change in gray matter concentration measured immediately after training predicted improvements in the speed of learning during re-adaptation one year later. Our study suggests that motor adaptation induces structural plasticity in primary motor circuits. In addition, it provides the first piece of evidence indicating that early structural changes induced by motor learning may impact on behavior up to one year after training.Fil: Landi, Sofía Mariana. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Cátedra de Fisiologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Baguear, Miguel Federico. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Cátedra de Fisiologia; ArgentinaFil: Della Maggiore, Valeria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Cátedra de Fisiologia; Argentin
Catalytic Combustion of Waste Streams Coming from the Solvent Recovery Stage of a Packaging Industry
Esters and alcohols are widely used as solvents in the packaging industry. They contribute to the increase of volatile organic compound (VOC) emissions and, as such, represent a serious air pollution problem that must be faced. To this end, two main strategies can be pursued: solvent recovery and/or incineration, the former being of course preferred. Solvent recovery consists of an activated carbon plant, which adsorbs the post-printing exhaust solvents, and a distillation system, which separates the recovered solvent mixture. The waste streams coming from the solvent recovery stage need to be disposed, implying additional costs as well as safety issues. In this work, a low-cost perovskite-based catalyst, doped with a low amount of noble metal (Pt) and supported over a monolithic reactor, was used to run lab-scale combustion tests for waste streams coming from the solvent recovery stage of the packaging industry Icimendue (www.icimen.com). Results of experimental tests support the validity of catalytic combustion of the waste streams as an alternative approach to their disposal
Estimación de los betas patrimoniales de los principales sectores económicos del Ecuador
El presente trabajo estima los betas patrimoniales para diferentes sectores del Ecuador en el
periodo 2017-2021. Con este fin se recolecta información de empresas a nivel latinoamericano
que sean comparables al caso ecuatoriano, ya que, en Ecuador no existe un mercado de valores
desarrollado y suficientemente líquido. La metodología utilizada para estimar los betas está
sustentada en el modelo CAPM, misma que no se ha realizado de forma adecuada en el país.
Los resultados obtenidos muestran que el sector de Manufactura (excepto refinación de petróleo)
y construcción tienen betas superiores a 1, es decir estos sectores son más sensibles ante las
variaciones en el mercado. Los sectores de Enseñanza, Servicios sociales y de salud,
Transporte, Comercio y Agricultura, ganadería, caza y silvicultura tienen betas inferiores a 1 lo
que implica que son menos riesgosas y sus rendimientos son menos volátiles con respecto al
mercado. La información proporcionada sirve como referencia para inversionistas, reguladores,
autoridades financieras u otros grupos de interés, considerando la incertidumbre del mercado
estas pueden variar con el tiempo, dependiendo de las condiciones del mercado y de la evolución
del sector.This paper estimates the equity betas for different sectors in Ecuador during the period of 2017-
2021. To achieve this, information is collected from Latin American companies that are
comparable to the Ecuadorian case, since Ecuador does not have a developed and sufficiently
liquid stock market. The methodology used to estimate the betas is based on the CAPM model,
which has not been previously used in the country. The results obtained show that the
Manufacturing sector (excluding oil refining) and Construction have betas greater than 1, meaning
that these sectors are more sensitive to market fluctuations. The sectors of Education and Social
Services, Transportation, Commerce, and Agriculture, Livestock, Hunting, and Forestry have
betas less than 1, which implies that they are less risky and their returns are less volatile with
respect to the market. The information provided serves as a reference for investors, regulators,
financial authorities, or other stakeholders, considering the market uncertainty that can vary over
time, depending on market conditions and sector evolution.0000-0003-2218-621
La traduzione di un'oralità popolare mitica: Louis-Ferdinand Céline in italiano
Salt Stress Induces Differentiated Nitrogen Uptake and Antioxidant Responses in Two Contrasting Barley Landraces from MENA Region
Gli oli essenziali contro la mosca carnaria Lucilia sericata agente di miasi cutanea.
Introduzione. A livello mondiale, le miasi sono un grave problema sia medico che veterinario. Negli ospedali, le miasi provocano seri problemi ai pazienti allettati mentre, negli allevamenti ovini, provocano ingenti danni colpendo milioni di pecore ogni anno con riscontri economici che sono stati stimati in circa 280 milioni di $ nella sola Australia. Nella miasi, le femmine gravide di mosche carnarie, attratte da stimoli olfattivi, depongono le uova in prossimità di ferite aperte o di orifizi di mammiferi. Le larve penetrano nella cute lesionata, invadendo i tessuti dell’ospite nutrendosene e determinando lo stato patologico definito miasi.
Scopo. In questo lavoro la bioattività degli oli essenziali (OE) di Clinopodium nubigenum (Kunth) Kuntze e di Lavandula angustifolia Mill è stata valutata contro la mosca carnaria Lucilia sericata (Meigen) (Diptera: Calliphoridae), agente di miasi cutanee.
Materiali e metodi. Gli OE sono stati chimicamente analizzati e testati in laboratorio per l’attività ovideterrente e per la tossicità verso gli adulti e le uova di Lucilia sericata. Il possibile meccanismo di azione è stato valutato mediante test di inibizione dell’acetilcolinesterasi (AChE) ed, infine, gli OE sono stati saggiati per le proprietà antibatteriche e antimicotiche.
Risultati. I risultati hanno indicato che alla dose di 0,8 μL cm-2, entrambi gli OE sono in grado di inibire completamente l’ovideposizione di L. sericata fino a 3 ore e, dopo 24 ore, dell’82,7% e del 89,5% per L. angustifolia e per C. nubigenum, rispettivamente. I due OE sono risultati anche tossici per contatto/fumigazione sia per le uova che per gli adulti mostrando valori di CL50 embrionale di 0,07 e 0,48 μL cm-2 mentre, per gli adulti, i valori di DL50 erano 0,278 e 0,393 μL per individuo per C. nubigenum e L. angustifolia, rispettivamente. L'inibizione dell'AChE in L. sericata (IC50 = 67,450 e 79,495 mg L-1 per C. nubigenum e L. angustifolia, rispettivamente) indica un meccanismo di azione neurotossico indiretto.
Conclusioni. L’utilizzo degli OE di C. nubigenum e L. angustifolia come trattamento preventivo contro l’agente di miasi L. sericata potrebbe ampliare lo spettro molto ristretto di alternative ecologiche e rispettose del benessere degli animali ai fitofarmaci sintetici e alle cruente procedure chirurgiche (mulesing) attualmente praticate per il controllo delle miasi. Infine, le proprietà antibatteriche e antimicotiche osservate per gli OE di C. nubigenum e L. angustifolia suggeriscono che un trattamento topico potrebbe contribuire alla prevenzione di infezioni secondarie
Apicultura Argentina: contexto fundacional y elementos de resiliencia del sector
La apicultura en la Argentina se inició a mediados del siglo XIX con la introducción de un número pequeño de colmenas de Apis mellifera L. en eventos puntuales e históricamente registrados. El mito fundacional enuncia que proliferaron dada la abundancia de flora silvestre. El desarrollo técnico de la cadena de valor se potenció en las primeras décadas del siglo XX, apoyado por actores definidos, que convirtieron al sector en uno de los principales proveedores de miel en el mercado internacional. Adversidades sanitarias y alteraciones en las condiciones ambientales debidas, principalmente, a cambios en el uso de la tierra que condicionan la apicultura a escala global han tenido un impacto importante. Las estrategias desarrolladas en los sectores de investigación y desarrollo, su extensión y adopción por productores deseosos de continuar en la apicultura han permitido la resiliencia frente a diferentes crisis.Beekeeping in Argentina began in the middle of the 19th century with the introduction of a small number of hives of Apis mellifera L. in specific and historically recorded events. The founding myth states that they proliferated due to the abundance of wild flora. The technical development of the value chain was strengthened in the first decades of the 20th century, supported by defined actors, which led the sector to become one of the main suppliers of honey in the international market. Sanitary adversities and alterations in the environment mainly due to changes in land use, which condition beekeeping on a global scale, have had a significant impact. The strategies developed in the research and development sectors, their extension and adoption by producers eager to continue in beekeeping have allowed resilience in the face of different crises.EEA Delta del ParanáFil: Basilio, Alicia Mabel. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Lopez, Valeria Carolina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Delta del Paraná; Argentina.Fil: Lopez, Valeria Carolina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Landi, Lucas. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; ArgentinaFil: Landi, Lucas. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Mellado, Lorena M. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Pedraza, Facundo. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Molina, Gonzalo Alberto Roman. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Avicultura, Cunicultura y Apicultura; ArgentinaFil: Gurini, Laura Beatriz. Profesional independiente. Programa Apícola Nacional PROAPI-INTA; Argentin
Human iPSC modelling of a familial form of atrial fibrillation reveals a gain of function of I-f and I-CaL in patient-derived cardiomyocytes
Aims: Atrial fibrillation (AF) is the most common type of cardiac arrhythmias, whose incidence is likely to increase with the aging of the population. It is considered a progressive condition, frequently observed as a complication of other cardiovascular disorders. However, recent genetic studies revealed the presence of several mutations and variants linked to AF, findings that define AF as a multifactorial disease. Due to the complex genetics and paucity of models, molecular mechanisms underlying the initiation of AF are still poorly understood. Here we investigate the pathophysiological mechanisms of a familial form of AF, with particular attention to the identification of putative triggering cellular mechanisms, using patient's derived cardiomyocytes (CMs) differentiated from induced pluripotent stem cells (iPSCs). Methods and results: Here we report the clinical case of three siblings with untreatable persistent AF whose whole-exome sequence analysis revealed several mutated genes. To understand the pathophysiology of this multifactorial form of AF we generated three iPSC clones from two of these patients and differentiated these cells towards the cardiac lineage. Electrophysiological characterization of patient-derived CMs (AF-CMs) revealed that they have higher beating rates compared to control (CTRL)-CMs. The analysis showed an increased contribution of the If and ICaL currents. No differences were observed in the repolarizing current IKr and in the sarcoplasmic reticulum calcium handling. Paced AF-CMs presented significantly prolonged action potentials and, under stressful conditions, generated both delayed after-depolarizations of bigger amplitude and more ectopic beats than CTRL cells. Conclusions: Our results demonstrate that the common genetic background of the patients induces functional alterations of If and ICaL currents leading to a cardiac substrate more prone to develop arrhythmias under demanding conditions. To our knowledge this is the first report that, using patient-derived CMs differentiated from iPSC, suggests a plausible cellular mechanism underlying this complex familial form of AF
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