341 research outputs found
Seasonality of coastal upwelling trends in the Mauritania-Senegalese region under RCP8.5 climate change scenario
The Mauritania-Senegalese upwelling region (MSUR), the southernmost region of the Canary current upwelling system, is well-known for its coastal productivity and the key role it plays in enriching the oligotrophic open ocean through the offshore transport of the upwelled coastal waters. The great ecological and socio-economic importance makes it necessary to evaluate the impact of climate change on this region. Hence, our main objective is to examine the climate change signal over the MSUR with a high resolution regional climate system model (RCSM) forced by the Earth system model MPI-ESM-LR under RCP8.5 scenario. This RCSM has a regional atmosphere model (REMO) coupled to a global ocean model (MPIOM) with high-resolution in the MSUR, which allows us to evaluate the wind pattern, the ocean stratification, as well as the upwelling source water depth, while maintaining an ocean global domain. Under RCP8.5 scenario, our results show that the upwelling favourable winds of the northern MSUR are year-round intensified, while the southern MSUR presents a strengthening in winter and a weakening in MarchâApril. Along with changes in the wind pattern, we found increased ocean stratification in the spring months. In those months southern MSUR presents a shallowing of the upwelling source water depth associated to changes in both mechanisms. However, in winter the whole MSUR shows a deepening of the upwelling source water depth due to the intensification of the upwelling favourable winds, with the increased ocean stratification playing a secondary role. Our results demonstrate the need to evaluate the future evolution of coastal upwelling systems taking into account their latitudinal and seasonal variability and the joint contribution of both mechanisms.publishedVersio
Feature Extraction and Classification of Biosignals - Emotion Valence Detection from EEG Signals
In thisworkavalencerecognitionsystembasedonelectroencephalogramsispresented.Theperformanceof
the systemisevaluatedfortwosettings:singlesubjects(intra-subject)andbetweensubjects(inter-subject).
The featureextractionisbasedonmeasuresofrelativeenergiescomputedinshorttimeintervalsandcertain
frequencybands.Thefeatureextractionisperformedeitheronsignalsaveragedoveranensembleoftrialsor
on single-trialresponsesignals.Thesubsequentclassificationstageisbasedonanensembleclassifier,i.e.a
random forestoftreeclassifiers.Theclassificationisperformedconsideringtheensembleaverageresponsesof
all subjects(inter-subject)orconsideringthesingle-trialresponsesofsinglesubjects(intra-subject).Applying
a properimportancemeasureoftheclassifier,featureeliminationhasbeenusedtoidentifythemostrelevant
features of the decision making.info:eu-repo/semantics/publishedVersio
Characterization of neutrino signals with radiopulses in dense media through the LPM effect
We discuss the possibilities of detecting radio pulses from high energy
showers in ice, such as those produced by PeV and EeV neutrino interactions. It
is shown that the rich radiation pattern structure in the 100 MHz to few GHz
allows the separation of electromagnetic showers induced by photons or
electrons above 100 PeV from those induced by hadrons. This opens up the
possibility of measuring the energy fraction transmitted to the electron in a
charged current electron neutrino interaction with adequate sampling of the
angular distribution of the signal. The radio technique has the potential to
complement conventional high energy neutrino detectors with flavor information.Comment: 5 pages, 4 ps figures. Submitted to Phys. Rev. Let
Pilot study on university students' opinion about STEM studies at higher education
The percentages of women enrolled in higher education in the
STEM sector are significantly lower than those of men. Overall,
gender representation in science, technology, engineering and mathematics
degrees in Europe is not balanced. The Leaky Pipeline phenomenon,
marked by gender stereotypes, makes the latent gender
gap a relevant topic of study. Studies exist on academic performance,
self-perception, self-efficacy, outcome expectations; however, studying
gender stereotypes linked to STEM studies is also essential. It
is necessary to know the social and family context in which young
people have grown up, as well as their perception of such studies.
To study gender stereotypes of university students about STEM
studies, a questionnaire has been designed for empirical validation.
For the design of the instrument, to be validated, items from other
instruments have been taken and adapted to Spanish. After the
design of the instrument, an online pilot study has been applied
in the University of Salamanca, the University of Valencia and the
Polytechnic University of Valencia. A total of 115 people answered
the questionnaire. The results of the pilot study reveal that the
study sample is not particularly marked by gender stereotypes
about gender equality in STEM. Also, the sample is receptive to
learning about science and applying it in their lives. On the other
hand, the idea that women have to give up their studies and careers
to look after their families and children is rejected. The idea that
men are more interested in university studies than women is also
rejected. At the same time, the sample is aware of the difficulties
that women encounter in the STEM sector. Another optimistic point
of the results is that there are no alarming data on bad experiences
due to gender. In the future, the study will be replicated on a larger
scale
Search for and Using Genetic Programming Event Selection
We apply a genetic programming technique to search for the double Cabibbo
suppressed decays and .
We normalize these decays to their Cabibbo favored partners and find
\Lambda_c^+ \to p K^+ \pi^-\Lambda_c^+ \to p K^-
\pi^+ and D_s^+ \to K^+ K^+
\pi^-D_s^+ \to K^+ K^- \pi^+ where
the first errors are statistical and the second are systematic. Expressed as
90% confidence levels (CL), we find and respectively.
This is the first successful use of genetic programming in a high energy
physics data analysis.Comment: 10 page
Measurement of the D+ and Ds+ decays into K+K-K+
We present the first clear observation of the doubly Cabibbo suppressed decay
D+ --> K-K+K+ and the first observation of the singly Cabibbo suppressed decay
Ds+ --> K-K+K+. These signals have been obtained by analyzing the high
statistics sample of photoproduced charm particles of the FOCUS(E831)
experiment at Fermilab. We measure the following relative branching ratios:
Gamma(D+ --> K-K+K+)/Gamma(D+ --> K-pi+pi+) = (9.49 +/- 2.17(statistical) +/-
0.22(systematic))x10^-4 and Gamma(Ds+ --> K-K+K+)/Gamma(Ds+ --> K-K+pi+) =
(8.95 +/- 2.12(statistical) +2.24(syst.) -2.31(syst.))x10^-3.Comment: 10 pages, 8 figure
A Non-parametric Approach to the D+ to K*0bar mu+ nu Form Factors
Using a large sample of D+ -> K- pi+ mu+ nu decays collected by the FOCUS
photoproduction experiment at Fermilab, we present the first measurements of
the helicity basis form factors free from the assumption of spectroscopic pole
dominance. We also present the first information on the form factor that
controls the s-wave interference discussed in a previous paper by the FOCUS
collaboration. We find reasonable agreement with the usual assumption of
spectroscopic pole dominance and measured form factor ratios.Comment: 14 pages, 5 figures, and 2 tables. We updated the previous version by
changing some words, removing one plot, and adding two tables. These changes
are mostly stylisti
Measurements of Branching Ratios
Using data collected by the fixed target Fermilab experiment FOCUS, we
measure the branching ratios of the Cabibbo favored decays , , and relative to to be
, , and ,
respectively. We report the first observation of the Cabibbo suppressed decay
and we measure the branching ratio relative to
to be . We also set 90%
confidence level upper limits for and relative to to
be 0.12 and 0.05, respectively. We find an indication of the decays and and set
90% confidence level upper limits for the branching ratios with respect to
to be 0.12 and 1.72, respectively. Finally, we
determine the 90% C.L. upper limit for the resonant contribution relative to to be 0.10.Comment: 14 pages, 8 figure
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