5,445 research outputs found
Morphology of the larval stages of Macropodia czernjawskii (Brandt, 1880) (Decapoda, Brachyura, Inachidae) reared in the laboratory
The complete larval development of Macropodia czernjawskii (Brandt, 1880), is described and illustrated for the first time. Larvae were reared in the laboratory and development consisted of two zoeal stages and a megalopa. The main difference in the zoeal stages is the absence of lateral spines on the telson furcae, which allow it to be distinguished from the remaining species of Macropodia as well as from the zoeae of most majoids.This study was funded by the Spanish “Ministerio de Ciencia e Innovación, Plan Nacional I+D” and the European FEDER funds through project MEGALOPADN (CGL2009–11225).Peer reviewe
Soil-Structure Interaction Simulations Taking into Account the Transient Propagation of Seismic Waves
In this contribution we present a strategy to investigate the vibrations of build ings subjected to a transient seismic excitation, including the soil-structure inte ract ion . The proposed simulation method can be helpful during the design of earthquake-resistant structures in seismic active areas as well as for the design of vibration reduction measures for buildings subjected to surrounding emissions like vibrations induced by traffic or ma chine foundations. The structures and their foundation as well as parts of the soil arc modeled by Finite Element Method (FEM). The far field is idealized as an infinite half space and modeled with the Scaled Boundary Finite Element Method (SBFEM). Both methods arc coupled at the common inter face. This approach fulfills exactly the Sommer feld radiation condition. The seismic excitation is idealized as a plane wave propagating toward the structure with an arbitrary angle with respect to the soil surface. The 3D seismic wave field, caused by the wave passage at the near field boundary, is transformed into boundary tractions , which arc then applied at the interface between the near and far fields. We present an application of the proposed method for a group of three buildings, which interact with each other through the soil during the propagation of the transient seismic waves. Although not shown here, the proposed method can handle nonlinear material properties assigned to any clement of FEM part
Assessing Single Upconverting Nanoparticle Luminescence by Optical Tweezers
We report on stable, long-term immobilization and localization of a single colloidal Er3+/Yb3+ codoped upconverting fluorescent nanoparticle (UCNP) by optical trapping with a single infrared laser beam. Contrary to expectations, the single UCNP emission differs from that generated by an assembly of UCNPs. The experimental data reveal that the differences can be explained in terms of modulations caused by radiation-trapping, a phenomenon not considered before but that this work reveals to be of great relevanceThis work was supported by the Spanish Ministerio de Educación y Ciencia (MAT2010–16161 and MAT2013–47395-C4–1-R). P.H.G. thanks the Spanish Ministerio de Economía y Competitividad (MINECO) for the Juan de la Cierva program. P.R.S thanks the Spanish Ministerio de Economía y Competitividad (MINECO) for the “Promoción 14 del talento y su Empleabilidad en I+D+i” statal program. Fondazione Cariverona (Verona, Italy) is gratefully acknowledged for financial support in the frame of the project “Verona Nanomedicine Initiative
Inter-channel Granger Causality for Estimating EEG Phase Connectivity Patterns in Dyslexia
Methods like Electroencephalography (EEG) and magnetoencephalogram (MEG) record brain oscillations and provide an invaluable insight into healthy and pathological brain function. These signals are helpful to study and achieve an objective and early diagnosis of neural disorders as Developmental Dyslexia (DD). An atypical oscillatory sampling could cause the characteristic phonological difficulties of dyslexia at one or more temporal rates; in this sense, measuring the EEG signal can help to make an early diagnosis of DD. The LEEDUCA study conducted a series of EEG experiments on children listening to amplitude modulated (AM) noise with slow-rhythmic prosodic (0.5–1 Hz) to detect differences in perception of oscillatory ampling that could be associated with dyslexia. The evolution of each EEG channel has been studied in the frequency domain, obtaining the analytical phase using the Hilbert transform. Subsequently, the cause-effect relationships between channels in ach subject have been reflected thanks to Granger causality, obtaining matrices that reflect the interaction between the different parts of the brain. Hence, each subject was classified as belonging or not to the control group or the experimental group. For this purpose, two ensemble classification algorithms were compared, showing that both can reach acceptable classifying erformance in delta band with an accuracy up to 0.77, recall of 0.91 and AUC of 0.97 using Gradient Boosting classifier.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
¿Pueden los ordenadores aproximarnos al mundo físico? : análisis cualitativo de la integración de la computación creativa y la computación física en áreas no puramente tecnológicas
Treballs finals del Màster en Ensenyament i Aprenentatge en Entorns Digitals, Facultat de Pedagogia, Universitat de Barcelona, Any: 2015, Tutor: José Luis Rodríguez IlleraLa enseñanza de la programación en los centros escolares está ligada al desarrollo del
pensamiento computacional, de la capacidad de abstracción, de la algorítmica y de la
resolución de problemas. Pero la integración transversal de esta habilidad como medio
para expresar la creatividad, comunicar ideas e interaccionar tanto socialmente como
con otros ámbitos del conocimiento, es una aplicación a emergente de esta disciplina.
Este trabajo analiza a modo exploratorio algunos casos donde se utiliza la
computación creativa y la computación física como medio para conseguir aprendizajes
de otras disciplinas
Temperature dependence and temporal dynamics of Mn2+ upconversion luminescence sensitized by Yb3+ in codoped LaMgAl11O19
A detailed spectroscopic study of the upconversion properties in Mn2+-Yb3+ codoped LaMgAl11O19 is presented. Pulsed and continuous-wave infrared excitation in the 2F7/2--2F5/2 Yb3+ absorption peaks induces broad Mn2+ green emission at 19450 cm-1, which is assigned to the 4T1--6A1 transition in tetrahedral Mn2+ and sharp peaks associated with Yb3+-pairs luminescence. Both emissions have very different temporal evolution and can be separated by time-resolved spectroscopy. Among the different concentrations under investigation, the 2%Mn2+-5%Yb3+ codoped system presents the highest upconversion efficiency. The corresponding emission remains visible to the naked eye up to 650 K. The time dependence of the Mn2+ luminescence upon Yb3+ excitation shows distinct behaviors for different doping concentrations. The temporal evolution of the intensity for the diluted system doped with 2%Mn2+ and 5%Yb3+ together with the pure manganese compound doped with 1%Yb3+, as well as the temperature dependence of the upconversion emission intensity and lifetime are relevant to identify the underlying upconversion mechanisms. We show that the main processes responsible for upconversion in this doubly transition-metal rare-earth doped oxide are both ground-state absorption (GSA)/excited-state absorption and GSA/energy-transfer upconversion. An analysis of these processes yielding highly efficient luminescence is discussed on the basis of crystal structure and dopants.This work was financially supported by the Spanish Ministerio de Ciencia e Innovación (Project No. MAT2008-
06873-C02-01/MAT) and the MALTA-Consolider Ingenio 2010 (Reference No. CSD2007-00045). R.M.-R. thanks the
Spanish MEC for a FPI research grant (Reference No. BES-2006-13359)
Adiciones al catálogo pteridológico gallego
Se comenta la localización y ecología de las poblaciones de diversas especies de helechos del género Isoetes que constituyen novedades para el catálogo florístico gallego así como nuevas localidades de otros pteridófitos de distribución fragmentada o inclRomero M. I., Rodríguez Guitián M. A. & Rubinos M. 2004. Addenda to the pteridophyte catalogue of Galicia (NW of Iberian Peninsula). Bot. Complut. 28: 51-55 (2004). This paper comments on the distribution and ecology of six species of rare/threatened ferns in the northwest Iberian Peninsula, including two species of the genus Isoetes not previously recorded from this region. New locations are also reported for other pteridophytes with fragmented distribution or listed in the Habitats Directive 92/43/EEC (Annex II), namely Stegnogramma pozoi, Vandenboschia speciosa, and Culcita macrocarpa
The orientation of lugdunum conuenarum and the celtic feasts marking the start of the seasons in ancient gaul
There is a long-lasting debate, started in the nineteenth century by d‟Arbois de Jubainville and Jullian, among others, regarding the pan-Celtic nature of the mid-season (or rather, start of season) feasts known
from the Mediaeval Ireland (set on 1st November, February, May and August). D‟Arbois indicated that one of these feasts coincided with the festival celebrated during Roman times at Lugdunum (Lyon) on August 1st
from 12 BC onwards. We recently verified that the orientation of the earlier parts of this Roman colony were laid out facing the sunrise on this date since its foundation in 43 BC, prior to any possible link with Augustus.
This fact prompted us to investigate the orientation of other Roman cities in Gaul, particularly those named Lugdunum which still contain Roman buildings capable of being measured. The most complex of these is Lugdunum Conuerarum (present-day Saint-Bertrand-de-Comminges). With a Celtic name and mixed Aquitaine-Latin culture, it is oriented towards the sunrise on February 1st. Other cities in Gaul and Hispania have also been considered, which have similar orientations. We therefore verify the pan-Celtic character of the mid-season feasts. Finally, we present the hypothesis that the conversion of these feasts from a luni-solar calendar to the solar Julian calendar took place in the centre of Gaul at some time between the reigns of Caesar and Augustus. At a later stage, this model would be exported by early Christianity into Ireland, then serving as an interpretative inspiration for scholars such as d‟Arbois de Jubainville and othersS
Causal Mechanisms of Dyslexia Via Connectogram Modeling of Phase Synchrony.
This paper introduces connectogram modeling of electroencephalography (EEG) signals as a novel approach to represent causal relationships and information flow between different brain regions. Connectograms are graphical representations that map the connectivity between neural nodes or EEG channels through lines and arrows of varying thickness and directionality. Here, interchannel phase connectivity patterns were analyzed by computing Granger causality to quantify the magnitude and direction of causal effects. The resulting weighted, directed connectograms displayed differences in functional integration between individuals with developmental dyslexia versus fluent readers when processing 4.8 Hz amplitude-modulated noise, designed to elicit speech encoding mechanisms. Machine learning classification was subsequently implemented to distinguish participant groups based on characteristic connectivity fingerprints. The methodology integrates signal filtering, instantaneous phase analysis via Hilbert transform, Granger causality computation between all channel pairs, automated feature selection using novel mutual information filtering, construction of directed weighted connectograms, and Gradient Boosting classification. Classification analysis successfully discriminates connectivity patterns, directly implicating theta and gamma bands (AUC 0.929 and 0.911, respectively) resulting from rhythmic auditory stimulation. Results demonstrated altered cross-regional theta
and gamma band oscillatory connectivity in dyslexia during foundational auditory processing, providing perspectives on multisensory and temporal encoding inefficiencies underlying language difficultiesUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
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