On the instability and constraints of the interaction between number representation and spatial attention in healthy humans. A concise review of the literature and new experimental evidence

.The relationship between number and space representation is still one of the most debated topics in studies of mathematical cognition. Here we offer a concise review of two important behavioral effects that have pointed out the use of a spatially left-to-right oriented mental number line (MNL) in healthy participants: the SNARC effect and the attentional SNARC effect (Att-SNARC). Following a brief summary of seminal investigations on the introspective properties of the MNL, we review recent empirical evidence and theories on the functional origin of the SNARC effect, where upon left/right response choices faster reaction times are found for small numbers with left-side responses and for large numbers with right-side responses. Then we offer a summary of the studies that have investigated whether the mere perception of visual Arabic numbers presented at central fixation can engender spatially congruent lateral shifts of attention, ie, leftward for small numbers and rightward for large ones, ie, the Att-SNARC effect. Finally, we summarize four experiments that tested whether the Att-SNARC depends on an active rather than passive processing of centrally presented digit cues. In line with other recent studies, these experiment do not replicate the original Att-SNARC and show that the mere perception of Arabic numerals does not trigger automatic shifts of attention. These shifts are instead found when the task requires the explicit left/right spatial coding of digit cues, ie, Spatial Att-SNARC (Fattorini et al., 2015b). Nonetheless, the reliability of the Spatial Att-SNARC effect seems not as strong as that of conventional SNARC effects where left/ right codes are mapped onto responses rather than directly mapped on digit cues. Comparing the magnitude of digits to a numerical reference, ie, "5," also produced a Magnitude Comparison Att-SNARC that was weaker than the spatial one. However, the reliability of this Magnitude Comparison Att-SNARC should be considered with caution because, like in a study by Zanolie and Pecher (2014), we recently failed to replicate this effect in a separate behavioral-eventrelated potentials study in preparation (Fattorini et al., 2015a). All together the results from the present series of experiments support the hypothesis that spatial coding is not an intrinsic part of number representation and that number-space interaction is determined by the use of stimulus-or response-related spatial codes in the task at han

Type II Supernovae as Standardized Candles

We present evidence for a correlation between expansion velocities of the ejecta of Type II plateau supernovae and their bolometric luminosities during the plateau phase. This correlation permits one to standardize the candles and decrease the scatter in the Hubble diagram from ~1 mag to a level of 0.4 and 0.3 mag in the V and I bands, respectively. When we restrict the sample to the eight objects which are well in the Hubble flow (cz > 3,000 km/s) the scatter drops even further to only 0.2 mag (or 9% in distance), which is comparable to the precision yielded by Type Ia supernovae and far better than the ``expanding photosphere method'' applied to Type II supernovae. Using SN 1987A to calibrate the Hubble diagrams we get Ho=55+/-12.Comment: 9 pages, 3 figures, 1 table, accepted by ApJ

T-WAS and T-XAS algorithms for fiber-loop optical buffers

In optical packet/burst switched networks fiber loops provide a viable and compact means of contention resolution. For fixed size packets it is known that a basic void-avoiding schedule (VAS) can vastly outperform a more classical pre-reservation algorithm as FCFS. For the setting of a uniform distributed packet size and a restricted buffer size we proposed two novel forward-looking algorithms, WAS and XAS, that, in specific settings, outperform VAS up to 20% in terms of packet loss. This contribution extends the usage and improves the performance of the WAS and XAS algorithms by introducing an additional threshold variable. By optimizing this threshold, the process of selectively delaying packet longer than strictly necessary can be made more or less strict and as such be fitted to each setting. By Monte Carlo simulation it is shown that the resulting T-WAS and T-XAS algorithms are most effective for those instances where the algorithms without threshold can offer no or only limited performance improvement

Selection Effects, Biases, and Constraints in the Calan/Tololo Supernova Survey

We use Monte Carlo simulations of the Calan/Tololo photographic supernova survey to show that a simple model of the survey's selection effects accounts for the observed distributions of recession velocity, apparent magnitude, angular offset, and projected radial distance between the supernova and the host galaxy nucleus for this sample of Type Ia supernovae (SNe Ia). The model includes biases due to the flux-limited nature of the survey, the different light curve morphologies displayed by different SNe Ia, and the difficulty of finding events projected near the central regions of the host galaxies. From these simulations we estimate the bias in the zero-point and slope of the absolute magnitude-decline rate relation used in SNe Ia distance measurements. For an assumed intrinsic scatter of 0.15 mag about this relation, these selection effects decrease the zero-point by 0.04 mag. The slope of the relation is not significantly biased. We conclude that despite selection effects in the survey, the shape and zero-point of the relation determined from the Calan/Tololo sample are quite reliable. We estimate the degree of incompleteness of the survey as a function of decline rate and estimate a corrected luminosity function for SNe Ia in which the frequency of SNe appears to increase with decline rate (the fainter SNe are more common). Finally, we compute the integrated detection efficiency of the survey in order to infer the rate of SNe Ia from the 31 events found. For a value of Ho=65 km/sec/Mpc we obtain a SN Ia rate of 0.21(+0.30)(-0.13) SNu. This is in good agreement with the value 0.16+/-0.05 SNu recently determined by Capellaro et al. (1997).Comment: 36 pages, 19 figures as extra files, to appear in the A

Monitorización de señales biomédicas en sistemas Android

El propósito fundamental del proyecto es conseguir la lectura de muestras en tiempo real con unos plazos de captura de las mismas muy estrictos, con el fin de no perder ninguna muestra. El proyecto parte de una aplicación en espacio de usuario que presentaba unas pérdidas en la recepción de muestras de entre un 1 y un 2 % respecto al conjunto total de muestras enviadas originalmente. Se observó que si además de ejecutar esta aplicación en espacio de usuario, se ejecutaba otra tarea en paralelo, el número de muestras perdidas se disparaba. Era necesario realizar una descarga de la CPU. Para conseguirlo, se ha utilizado la Unidad Programable en Tiempo-real de la BeagleBone Black, que es un hardware específicamente diseñado para este tipo de operaciones, es decir, para realizar tareas sencillas en tiempo real; principalmente se programa en ensamblador y facilita la interacción entre el código ensamblador y una aplicación en espacio de usuario. Una vez implementada la solución con éxito, se evita la pérdida muestras en el proceso. Además, se consigue descargar la CPU, de manera que es posible ejecutar otras tareas de forma paralela. Finalmente, se consigue que la BeagleBone Black se comunique con una aplicación Android mediante Bluetooth. Esta aplicación facilita a un paciente la recogida de información de su electrocardiograma, para que posteriormente, o incluso en tiempo real, sea un médico el que trate de analizarla e interpretarla. Para que la comunicación entre médico y paciente sea posible, es necesario que ambos dispongan de conexión a internet, ya que la interacción se realiza a través de un servidor, el cual recibe la información de un dispositivo y la retransmite al otro

Environmental education and the valuation of São Tomé and Príncipe’s natural heritage: contributions and challenges for local development

[Resumo] O património natural de São Tomé e Príncipe tem vindo a ser identificado e reconhecido pela comunidade científica, processo em que se tem destacado mais a sua riquíssima diversidade biológica que a geológica, não obstante a sua relativa importância. O relacionamento da comunidade com os recursos naturais do arquipélago tem vindo a intensificar-se e a promover impactos significativos, como o atestam a progressiva depleção da floresta, a erosão costeira e a extração furtiva de inertes, entre outras situações identificadas. Promover um maior e melhor conhecimento do património natural de São Tomé e Príncipe, bem como de modelos de relacionamento mais harmoniosos entre a comunidade e este património, é um desígnio da Educação Ambiental. A Educação Ambiental torna-se promotora da sensibilização, formação, divulgação, promoção e valorização do conhecimento relativo ao património natural/ambiental, tornando-se um veículo de intervenção e desenvolvimento comunitário. Pode contribuir, assim, para o desenvolvimento do arquipélago aos seus vários níveis -abarcando múltiplos atores nesse processo educativo, nomeadamente estabelecimentos de ensino, organizações não-governamentais com preocupações ambientais e de desenvolvimento, ordens profissionais e poder político, entre outros– exigindo também o estabelecimento de uma rede de cooperação/parcerias essencial ao país e à defesa do seu património natural.[Abstract] The natural heritage of São Tomé and Príncipe archipelago has been identifed and recognized by the scientifc community, a process in which its rich biological diversity has been more prominent than geological diversity, despite its relative importance. The community’s relationship with the natural resources of the archipelago has been intensifying and promoting signifcant impacts, as evidenced by the progressive depletion of the forest, coastal erosion and furtive extraction of aggregates, among other identifed situations. To promote a greater and better knowledge of the natural heritage of São Tomé and Príncipe, as well as more harmonious relationship models between the community and this heritage, is a design of Environmental Education. Environmental Education becomes a promoter of the awareness, formation, dissemination, promotion and valorization of knowledge related to the natural / environmental heritage, becoming a vehicle for intervention and community development. It may contributes to the development of the archipelago at its various levels - encompassing multiple actors in this educational process, including educational establishments, non-governmental organizations with environmental and development concerns, professional orders and political power, among others - of a network of cooperation/partnerships essential to the country and the defense of its natural heritage

Conflictividad y derechos humanos en Ecuador

Analiza la conflictividad socio política expresada en la conflictividad con las oposiciones de derecha desplegada en el campo ideológico y el económico, destacando que con los actores empresariales se ha dado apertura al diálogo; y la conflictividad con los movimientos sociales, expresada en la criminalización de la protesta social y la judicialización, enfatizando en los conflictos con el movimiento indígena y los trabajadores públicos, evidenciando que con estos sectores no se propició el diálogo. Presenta la relación de los conflictos con los derechos constitucionales, evidenciado que los derechos de libertad, buen vivir y participación son los más afectados. Concluye señalando que para consolidar el modelo hegemónico se privilegia la versión antidialógica del conflicto

The Influence of 150-Cavity Binders on the Dynamics of Influenza A Neuraminidases as Revealed by Molecular Dynamics Simulations and Combined Clustering

Neuraminidase inhibitors are the main pharmaceutical agents employed for treatments of influenza infections. The neuraminidase structures typically exhibit a 150-cavity, an exposed pocket that is adjacent to the catalytic site. This site offers promising additional contact points for improving potency of existing pharmaceuticals, as well as generating entirely new candidate inhibitors. Several inhibitors based on known compounds and designed to interact with 150-cavity residues have been reported. However, the dynamics of any of these inhibitors remains unstudied and their viability remains unknown. This work reports the outcome of long-term, all-atom molecular dynamics simulations of four such inhibitors, along with three standard inhibitors for comparison. Each is studied in complex with four representative neuraminidase structures, which are also simulated in the absence of ligands for comparison, resulting in a total simulation time of 9.6µs. Our results demonstrate that standard inhibitors characteristically reduce the mobility of these dynamic proteins, while the 150-binders do not, instead giving rise to many unique conformations. We further describe an improved RMSD-based clustering technique that isolates these conformations – the structures of which are provided to facilitate future molecular docking studies – and reveals their interdependence. We find that this approach confers many advantages over previously described techniques, and the implications for rational drug design are discussed