Distribution of Oikopleura Dioica (Tunicata, Appendicularia) associated with a coastal frontal system (39°- 41°s) of the SW Atlantic ocean in the spawning area of Engraulis Anchoita anchovy

Among tunicates, the small planktonic appendicularians generally comprise a significant fraction of the mesozooplankton in frontal systems. The summer 2011 distribution (vertical and spatial) of Oikopleura dioica was studied in terms of abundance, biomass, estimation of egg production and population structure in the different sectors of the El Rincón coastal front, in the light of thermal and salinity gradients. Peaks of abundance of Engraulis anchoita larvae were compared to O. dioica patterns. Samples were collected with plankton nets of 67 µm and 200 µm at two layers, below and above the thermocline depth. CTD data profiles were also recorded. During this campaign high salinity waters were predominant in the estuarine area. Conversely, a thermal stratification was found, being more marked at the external stations of the front where the highest densities and biomass of O. dioica coincided with the highest E. anchoita larvae densities. The size structure of O. dioica was also associated with the thermal gradient. The smaller sizes were found in the homogeneous area at the coast where the temperature was higher around 22ºC. This front constitutes a suitable environment for O. dioica reproduction enhancing the survival rate and growth of several small pelagic fishes such as E. anchoita.Entre os tunicados, as pequenas apendiculárias planctônicas geralmente compreendem uma fração significativa do mesozooplâncton nos sistemas frontais. Foi estudada a distribuição (vertical e espacial) durante o verão de 2011 de Oikopleura dioica, em termos de abundância, biomassa, estimativa da produção de ovos e estrutura da população em diferentes setores da frente costeiro de El Rincón, segundo os gradientes de temperatura e salinidade. Picos de abundância de larvas de Engraulis anchoita foram comparados com os padrões de O. dioica. As amostras foram coletadas com redes planctônicas de 67 e 200 µm em duas profundidades, acima e abaixo da termoclina. Também foram registrados perfis de dados obtidos com CTD. Durante essa campanha, aguas de alta salinidade foram predominantes na área estuarina. No entanto, foi encontrada uma estratificação térmica, sendo mais acentuado nas estações externas da frente, onde as maiores densidades e biomassa de O. dioica foram registradas, coincidindo também com as maiores densidades de larvas de E. anchoita. A distribuição de tamanhos de O. dioica também foi associada ao gradiente térmico. Os menores tamanhos foram encontrados na região mais homogênea da costa, onde a temperatura apresentou cerca de 22ºC. Essa frente é um ambiente propício para a reprodução de O. dioica o que favorece também o aumento da sobrevivência e o crescimento de muitas espécies de pequenos peixes pelágicos, tais como E. anchoita.Fil: Spinelli, Mariela Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Guerrero, Raul Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; ArgentinaFil: Pajaro, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; ArgentinaFil: Capitanio, Fabiana Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentin

Mortality in low- and very low-risk patients undergoing cardiac surgery: Evaluation according to the EuroSCORE II as a new standard

Background: Only a few reports have analyzed low-risk patient outcomes and in every case, the risk was based on a logistic EuroSCORE ≤ 2. Since this original EuroSCORE overestimates surgical risk, we developed this study to prospectively evaluate the immediate results of cardiac surgery in patients with an expected mortality risk ≤ 2% according to the EuroSCORE II as a new gold standard. We also examined the cause of death and whether it could be considered preventable. Methods: A prospective risk stratification of all cardiac surgical patients treated at the Bue­nos Aires University Hospital of Argentina was performed between 2012 and 2014 using the EuroSCORE II. Causes of death were classified as preventable or not preventable. Results: From a total of 990 patients, 63.2% had EuroSCORE II ≤ 2 (low-risk group) and 32.5% EuroSCORE II < 1 (very low-risk group). In the low-risk group, in-hospital mortal­ity was 1.8%, whereas predicted mortality was 1.04% (AUC 0.765). The observed/expected ratio was 1.73 (95% CI 0.68–4.43) and the observed-expected difference was 0.76 (95% CI –0.68–2.10). Fifty-four percent of deaths were considered preventable. Conclusions: We propose to use and further validate the EuroSCORE II as a new standard for assessing low-risk patients. This model proved to be useful in evaluating the quality standards of local cardiac surgery. The review of cause of death in low-risk patients provided valuable information, which revealed potentially correctable issues. Adoption of a more demanding standard, as the EuroSCORE II to identify low-risk patients, avoids the sense of safety offered by previous versions of the score

Upwelling, a common phenomenon in the northern coast of the Rio de la Plata?

En este trabajo se estudiaron las escalas de variabilidad de la temperatura superficial del mar (TSM) en el Río de la Plata y los procesos físicos que las producen. Se utilizaron datos diarios satelitales de TSM y viento en superficie, con resoluciones espaciales de 10 y 25 kilómetros respectivamente, y datos de caudal de los tributarios para el período julio 2002 - julio 2008. Los resultados fueron validados con datos in situ. Se encuentra que la mayor parte de la varianza está asociada al ciclo anual, sencillamente porque la amplitud de la señal de verano a invierno es grande (mayor de 13°C). Sin embargo, ocurre abundante variabilidad en la escala sub-anual, fundamentalmente vinculada a la variabilidad sinóptica del viento, en el Río Exterior. El primer modo de variabilidad en esta escala está relacionado con vientos anómalamente intensos del este o el oeste, que fuerzan la ocurrencia de núcleos más cálidos o más fríos, respecto a la temperatura del agua circundante a lo largo de la costa norte del Río Exterior, entre Montevideo y Punta del Este. Los eventos fríos se observan con mayor frecuencia en los meses de primavera y verano, con anomalías de temperatura de hasta -5.5ºC y ocurren bajo condiciones de vientos intensos del este/noreste paralelos a la costa, lo que sugiere surgencia de agua más profunda. Los eventos de surgencia observados resultaron de gran persistencia, alcanzando en varios casos una duración mayor a un mes. También presentan un marcado ciclo estacional, resultando un fenómeno muy común en la estación cálida. Su ocurrencia también parece estar modulada por la descarga continental, en la medida que ésta modifica las condiciones de estratificación a lo largo de la costa.Fil: Luz Clara Tejedor, Moira. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Simionato, Claudia Gloria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Campetella, Claudia Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Moreira, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Guerrero, Raul Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; Argentin

síntesis, caracterización y aplicaciones

La Nanotecnología es un área de la ciencia relativamente nueva. No obstante, una gran parte de la comunidad científica considera que es la base del desarrollo tecnológico de los próximos años. Dentro del campo de estu dio de la nanotecnología encontramos las nanoestructuras metálicas. Estos nanomateriales presentan propiedades muy interesantes y diferentes a los materiales “en bulto” o a escala macroscópica; entre ellas, la conductividad eléctrica y las propiedades magnéticas, ópticas y de catálisis, propiedades que las hacen candidatas a innumerables aplicaciones en todos los campos de la tecnología. Desafortunadamente, como suele suceder en muchos ámbitos de la ciencia y la tecnología, es la comunidad científica que estudia un área concreta quien conoce en exclusiva esa información. Por ello, nuestro grupo de investigación ha escrito este libro intentando cum Nanoestructuras metálicas: síntesis, caracterización y aplicaciones viii plir dos objetivos principales: el primero, dar a conocer los últimos resultados de nuestras investigaciones con nanoestructuras metálicas y algunas de sus aplicaciones, dicha información va dirigida a la comunidad científica interesada en el área; el segundo objetivo es redactar un libro que sea útil para quienes estén interesados en esta ciencia aunque no tengan demasiada experiencia en el tema, para ello, cada capítulo cuenta con una parte introductoria en la que se presentan aspectos generales del tema que se trata. A su vez, se ha intentado emplear un lenguaje de fácil comprensión pero sin que se pierda la especificidad de cada tema. Finalmente, los autores de este libro queremos agradecer a nuestra alma mater, la Universidad Autónoma del Estado de México, por el apoyo recibido para la publicación del mismo, esperando poder contribuir así al fortalecimiento del área científica.El desarrollo de la tecnología siempre ha estado íntimamente relacionado con las necesidades del ser humano por controlar su entorno y los fenómenos naturales, esto con el objeto de lograr una mejor calidad de vida para las personas. Muchos de los descubrimientos científicos más importantes, como es el caso de las leyes de Newton o la teoría de la relatividad de Einstein, revolucionaron la tecnología dando paso a una nueva era, en la que todo se explica desde el principio fundamental de los átomos. Ello provocó que científicos como Richard Feyman, ganador del Premio Nobel de Física en 1965, empezaran a vislumbrar las posibilidades que presentaba la nanotecnología. Feyman mencionó que, al poder estudiar y entender el comportamiento de los átomos y las moléculas, se podrían interpretar de mejor manera los fenómenos en el universo, dando paso a la frase: “En el fondo hay espacio de sobra”

The salinity signature of the cross-shelf exchanges in the Southwestern Atlantic Ocean: Satellite observations

Satellite-derived sea surface salinity (SSS) data from Aquarius and SMOS are used to study the shelf-open ocean exchanges in the western South Atlantic near 35°S. Away from the tropics, these exchanges cause the largest SSS variability throughout the South Atlantic. The data reveal a well-defined seasonal pattern of SSS during the analyzed period and of the location of the export of low-salinity shelf waters. In spring and summer, low-salinity waters over the shelf expand offshore and are transferred to the open ocean primarily southeast of the river mouth (from 36°S to 37°30′S). In contrast, in fall and winter, low-salinity waters extend along a coastal plume and the export path to the open ocean distributes along the offshore edge of the plume. The strong seasonal SSS pattern is modulated by the seasonality of the along-shelf component of the wind stress over the shelf. However, the combined analysis of SSS, satellite-derived sea surface elevation and surface velocity data suggest that the precise location of the export of shelf waters depends on offshore circulation patterns, such as the location of the Brazil Malvinas Confluence and mesoscale eddies and meanders of the Brazil Current. The satellite data indicate that in summer, mixtures of low-salinity shelf waters are swiftly driven toward the ocean interior along the axis of the Brazil/Malvinas Confluence. In winter, episodic wind reversals force the low-salinity coastal plume offshore where they mix with tropical waters within the Brazil Current and create a warmer variety of low-salinity waters in the open ocean.Fil: Guerrero, Raul Alfredo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Piola, Alberto Ricardo. Ministerio de Defensa. Armada Argentina. Servicio de Hidrografia Naval; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Fenco, Harold. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Matano, Ricardo. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: Combes, Vincent. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: Chao, Yi. University of California at Los Angeles; Estados Unidos. Remote Sensing Solutions Inc.; Estados UnidosFil: James, Corinne. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: Palma, Elbio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Nacional del Sur. Departamento de Física; ArgentinaFil: Saraceno, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera; ArgentinaFil: Strub, P. Ted. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados Unido

The Salinity Signature of the Cross-Shelf Exchanges in the Southwestern Atlantic Ocean: Numerical Simulations

A high-resolution model is used to characterize the dominant patterns of sea surface salinity (SSS) variability generated by the freshwater discharges of the Rio de la Plata (RdlP) and the Patos/Mirim Lagoon in the southwestern Atlantic region. We identify three dominant modes of SSS variability. The first two, which have been discussed in previous studies, represent the seasonal variations of the freshwater plumes over the continental shelf. The third mode of SSS variability, which has not been discussed hitherto, represents the salinity exchanges between the shelf and the deep ocean. A diagnostic study using floats and passive tracers identifies the pathways taken by the freshwater plumes. During the austral winter (JJA) the plumes leave the shelf region north of the BMC. During the austral summer (DJF), the plumes are entrained more directly into the BMC. A sensitivity study indicates that the high frequency component of the wind stress forcing controls the vertical structure of the plumes while the low-frequency component of the wind stress forcing and the inter- annual variations of the RdlP discharge controls the horizontal structure of the plumes. Dynamical analysis reveals that the cross-shelf flow has a dominant barotropic structure and, therefore, the SSS anomalies detected by Aquarius represent net mass exchanges between the shelf and the deep ocean. The net cross-shelf volume flux is 1.21 Sv. This outflow is largely compensated by an inflow from the Patagonian shelf.Fil: Matano, Ricardo. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: Combes, Vincent. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: Piola, Alberto Ricardo. Ministerio de Defensa. Armada Argentina. Servicio de Hidrografia Naval; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Guerrero, Raul Alfredo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Palma, Elbio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Nacional del Sur. Departamento de Física; ArgentinaFil: Strub, P. Ted. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: James, Corinne. Oregon State University. College of Earth, Ocean and Atmospheric Sciences; Estados UnidosFil: Fenco, Harold. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Chao, Yi. Remote Sensing Solutions; Estados UnidosFil: Saraceno, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentin

Facile solventless synthesis of a nylon-6,6/silver nanoparticles composite and its XPS study

SINTESIS DE NANOPARTICULASSilver nanoparticles were synthesized and supported on thin nylon membranes by means of a simple method of impregnation and chemical reduction of Ag ions at ambient conditions. Particles of less than 10nm were obtained using this methodology, in which the nylon fibers behave as constrained nanoreactors. Pores on nylon fibres along with oxygen and nitrogen from amide moieties in nylon provide effective sites for in situ reduction of silver ions and for the formation and stabilization of Ag nanoparticles. Transmission electron microscopy (TEM) analysis showed that silver nanoparticles are well dispersed throughout the nylon fibers. Furthermore, an interaction betweenUAEME

Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action

Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or “golden rules,” for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Environmental factors that define the spawning and nursery areas for Percophis brasiliensis (Teleostei: Percophididae) in a multispecific reproductive coastal zone, El Rincón (39°–41°S), Argentina

The spatial distribution of Percophis brasiliensis at different maturity stages and its relationship to environmental factors was evaluated in the El Rincon area (39°–41°S) between 1994 and 2008 during eight cruises carried out in spring. For this, a canonical correspondence analysis was used. Results indicate that bottom temperature and bottom salinity horizontal gradient (BSHG) were the most important variables affecting the spatial distribution of P. brasiliensis maturity stages. Juveniles were mainly located in shallow waters with low salinity, high temperatures and vertical stratification. Conversely, gravid and running individuals were found in high BSHG and low temperatures. This link suggests that adults spawn in a well-defined area of hydrographic conditions that would tend to retain pelagic eggs and larvae, thus minimizing dispersal, and ensuring their transport from the spawning to nursery areas. On the coastal shelf of El Rincon, the water mass circulation shows an anti-cyclonic gyre whose recirculation cell during spring and summer is more constrained to inshore areas than during winter. Maximum reproductive activity of P. brasiliensis coincides with the highest retention period; therefore, dispersal of early-life stages (eggs) depends on the circulation pattern and transport pathway which would contribute importantly to its recruitment variability.Fil: Rodrigues, Karina Andrea. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jaureguizar, Andrés Javier. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Guerrero, Raul Alfredo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Universidad Nacional de Mar del Plata; Argentin