2,514 research outputs found
VISIR federation: Initial building steps (PILAR experience – work in progress)
Collaborative working as well as sharing resources and knowledge represent key points in today's development in all fields, including education. Know-how transfer and collaboration in learning and teaching are aspects promoted and sustained by institutional management as well as the European initiatives. Thus, leading to the idea of a federation which will facilitate engineering education. A consortium formed by five European universities decided to join efforts to provide to the community a federation, which could be used by different stakeholders interest in teaching, learning or developing new skills in the field of electronics. The proposed remote system, Virtual Instruments System in Reality, or VISIR in short, offers the possibility of working with real equipment and obtain the real-world/ real-time measurements. By developing such a VISIR federation some of the constraints of using remote labs, the ones associated with development and maintenance costs, and scalability, will be minimized.info:eu-repo/semantics/publishedVersio
Consumption of Acorns by Finishing Iberian Pigs and Their Function in the Conservation of the Dehesa Agroecosystem
Ameliorate QSPR Study of Alkyl Hydroperoxides
A set of linear and nonlinear functions of one and several variables are determined to predict refractive index, molar refraction, and density for a representative set of alkyl hydroperoxides. Quite satisfactory predictions can be made on the basis of these equations and in some cases it is necessary to resort to higher-order equations to get a very good quantitative description of physical properties. Some possible further extensions of this study are pointed out in order to get a step head in the understanding of the quan- titative structure-property relationships of alkyl hydroperoxides.Facultad de Ciencias Exacta
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Correlations between psychological tests and physiological responses during fear conditioning and renewal
Background: Anxiety disorders are characterized by specific emotions, thoughts and physiological responses. Little is known, however, about the relationship between psychological/personality indices of anxiety responses to fear stimuli. Methods: We studied this relationship in healthy subjects by comparing scores on psychological and personality questionnaires with results of an experimental fear conditioning paradigm using a visual conditioned stimulus (CS). We measured skin conductance response (SCR) during habituation, conditioning, and extinction; subsequently testing for recall and renewal of fear 24 hours later. Results: We found that multiple regression models explained 45% of the variance during conditioning to the CS+, and 24% of the variance during renewal of fear to the CS+. Factors that explained conditioning included lower levels of conscientiousness, increased baseline reactivity (SCL), and response to the shock (UCR). Low levels of extraversion correlated with greater renewal. No model could be found to explain extinction learning or extinction recall to the CS+. Conclusions: The lack of correlation of fear extinction with personality and neuropsychological indices suggests that extinction may be less determined by trait variables and cognitive state, and may depend more on the subject’s current emotional state. The negative correlation between fear renewal and extraversion suggests that this personality characteristic may protect against post-treatment relapse of symptoms of anxiety disorders
AE Aurigae: First detection of non-thermal X-ray emission from a bow shock produced by a runaway star
Runaway stars produce shocks when passing through interstellar medium at supersonic velocities. Bow shocks have been detected in the mid-infrared for several high-mass runaway stars and in radio waves for one star. Theoretical models predict the production of high-energy photons by non-thermal radiative processes in a number sufficiently large to be detected in X-rays. To date, no stellar bow shock has been detected at such energies. We present the first detection of X-ray emission from a bow shock produced by a runaway star. The star is AE Aur, which was likely expelled from its birthplace due to the encounter of two massive binary systems and now is passing through the dense nebula IC 405. The X-ray emission from the bow shock is detected at 30″ northeast of the star, coinciding with an enhancement in the density of the nebula. From the analysis of the observed X-ray spectrum of the source and our theoretical emission model, we confirm that the X-ray emission is produced mainly by inverse Compton upscattering of infrared photons from dust in the shock front.Instituto Argentino de RadioastronomíaFacultad de Ciencias Astronómicas y Geofísica
Systematic assessment of fluid responsiveness during early septic shock resuscitation: secondary analysis of the ANDROMEDA-SHOCK trial
BACKGROUND: Fluid boluses are administered to septic shock patients with the purpose of increasing cardiac output as a means to restore tissue perfusion. Unfortunately, fluid therapy has a narrow therapeutic index, and therefore, several approaches to increase safety have been proposed. Fluid responsiveness (FR) assessment might predict which patients will effectively increase cardiac output after a fluid bolus (FR+), thus preventing potentially harmful fluid administration in non-fluid responsive (FR-) patients. However, there are scarce data on the impact of assessing FR on major outcomes. The recent ANDROMEDA-SHOCK trial included systematic per-protocol assessment of FR. We performed a post hoc analysis of the study dataset with the aim of exploring the relationship between FR status at baseline, attainment of specific targets, and clinically relevant outcomes. METHODS: ANDROMEDA-SHOCK compared the effect of peripheral perfusion- vs. lactate-targeted resuscitation on 28-day mortality. FR was assessed before each fluid bolus and periodically thereafter. FR+ and FR- subgroups, independent of the original randomization, were compared for fluid administration, achievement of resuscitation targets, vasoactive agents use, and major outcomes such as organ dysfunction and support, length of stay, and 28-day mortality. RESULTS: FR could be determined in 348 patients at baseline. Two hundred and forty-two patients (70%) were categorized as fluid responders
Functional hybrid nanoemulsions for sumatriptan intranasal delivery
In recent years, advanced nanohybrid materials processed as pharmaceuticals have proved to be very advantageous. Triptans, such as the commercially available intranasal sumatriptan (SMT), are drugs employed in the treatment of painful migraine symptoms. However, SMT effectiveness by the intranasal route is limited by its high hydrophilicity and poor mucoadhesion. Therefore, we designed hybrid nanoemulsions (NE) composed of copaiba oil as the organic component plus biopolymers (xanthan, pectin, alginate) solubilized in the continuous aqueous phase, aiming at the intranasal release of SMT (2% w/v). Firstly, drug-biopolymer complexes were optimized in order to decrease the hydrophilicity of SMT. The resultant complexes were further encapsulated in copaiba oil-based nanoparticles, forming NE formulations. Characterization by FTIR-ATR, DSC, and TEM techniques exposed details of the molecular arrangement of the hybrid systems. Long-term stability of the hybrid NE at 25°C was confirmed over a year, regarding size (~ 120 nm), polydispersity (~ 0.2), zeta potential (~ −25 mV), and nanoparticle concentration (~ 2.1014 particles/mL). SMT encapsulation efficiency in the formulations ranged between 41–69%, extending the in vitro release time of SMT from 5 h (free drug) to more than 24 h. The alginate-based NE was selected as the most desirable system and its in vivo nanotoxicity was evaluated in a zebrafish model. Hybrid NE treatment did not affect spontaneous movement or induce morphological changes in zebrafish larvae, and there was no evidence of mortality or cardiotoxicity after 48 h of treatment. With these results, we propose alginate-based nanoemulsions as a potential treatment for migraine pain.Fil: Ribeiro, Lígia N. M.. Universidade Estadual de Campinas; BrasilFil: Rodrigues da Silva, Gustavo H.. Universidade Estadual de Campinas; BrasilFil: Couto, Verônica M.. Universidade Estadual de Campinas; BrasilFil: Castro, Simone R.. Universidade Estadual de Campinas; BrasilFil: Breitkreitz, Márcia C.. Universidade Estadual de Campinas; BrasilFil: Martinez, Carolina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Igartúa, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Prieto, Maria Jimena. Universidad Nacional de Quilmes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: de Paula, Eneida. Universidade Estadual de Campinas; Brasi
Multiplus: a modular high-performance multiprocessor
The MULTIPLUS project is currently under development at NCE/UFRJ, Brazil, aims at the study of parallel processing problems in MIMD environments. The project includes the development of a parallel shared-memory architecture and a UNIX-like operating operating system called MULTIPLIX. The MULTIPLUS achitecture uses an inverted n-cube multistage network to interconnect clusters of processing nodes designed around a double-bus system. As a consequence, the architecture is partitionable and modular. It cas easily and efficiently supportconfigurations ranging from workstations to powerful parallel supercomputers with up to 2048 processing nodes. The MULTIPLix operating system provides MULTIPLUS with an efficient computing environment for parallel scientific applications. MULTIPLIX uses the concept of thread, implements busy-waiting synchronization primitives very efficiently and carefully considers data locality and scientific processing requirements in the policies adopted for memory management and thread scheduling.O projeto MULTIPLUS, que está atualmente em desenvolvimento no NCE/UFRJ, objetiva o estudo de problemas de processamento paralelo em ambiente MIMD. O projeto inclui o desenvolvimento de uma arquitetura paralela com memória compartilhada e um sistema operacional tipo UNIX chamado MULTIPLIX. A arquitetura do MULTIPLUS usa uma rede de interconexão multiestágio do tipo n-cubo invertido para interligar clusters de nós de processamento projetados em torno de um sistema de barramento duplo. Como consequência a arquitetura é patrocinável e modular. Ela pode suportar eficientemente configurações cobrindo um espectro que vai desde estações de trabalho até poderosos supercomputadores contendo 2048 nós de processamento trabalhando em paralelo. O sistema operacional MULTIPLIX provê o MULTIPLUS com um ambiente eficiente de computação para aplicações científicas paralelas.O MULTIPLIX usa o conceito de "thread", implementa primitivas de sincronização de espera ocupara muito eficientemente e considera fortemente aspectos de localidade dos dados e requisitos de processamento científico nas políticas adotadas para gerenciamento de memória e escalonamento de "threads"
Relationships between Kováts retention indices and molecular descriptors of 1-(2-hydroxy)-3-arylpropane-1,3-diones
Experimental and theoretical results for retention index of a set of 20 beta-diketones are given. The quantitative structure-chromatographic retention relationships (QSRR) theory is employed and six molecular descriptors are chosen to compute the fitting polynomials. Multiple regression analysis yields satisfactory results when one resorts to several variables equations, instead of computing just one-variable formulae. Average absolute deviations from experimental results are rather low, which seems to point out the suitability of the present approach.Facultad de Ciencias Exacta
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