1,507 research outputs found
Perceptions of professional competences in Physical Education Teacher Education (PETE)
Students' skills acquisition is one of the main aims of higher education institutions. On the one hand, the development of professional competences is important, but on the other hand, it is known that professionals who feel competent have a more intrinsic motivation in their jobs. The goal of this study was to describe and detail the perceptions of students, graduates, and their university tutors about the level of acquisition by students of professional competences. The methodology was based on a descriptive and comparative study that included a total sample of 2075 participants of the Degree in Primary Teaching and the Degree in Physical Activity and Sport Science. All of them came from 21 different universities of Spain: 345 university tutors, 1243 students, and 487 graduates. The instrument used was a competences perception questionnaire. The statistical analysis included means, standard deviations, and an ANOVA analysis. The results show discrepancies in the perceptions of proficiency levels between students and graduates, on one hand, and university tutors, on the other. Likewise, there was general agreement that competences related to critic capacity and motor games were the most acquired and programs for individuals with special needs were the least acquired
Adiabatic Approximation in the Density Matrix Approach: Non-Degenerate Systems
We study the adiabatic limit in the density matrix approach for a quantum
system coupled to a weakly dissipative medium. The energy spectrum of the
quantum model is supposed to be non-degenerate. In the absence of dissipation,
the geometric phases for periodic Hamiltonians obtained previously by M.V.
Berry are recovered in the present approach. We determine the necessary
condition satisfied by the coefficients of the linear expansion of the
non-unitary part of the Liouvillian in order to the imaginary phases acquired
by the elements of the density matrix, due to dissipative effects, be
geometric. The results derived are model-independent. We apply them to spin 1/2
model coupled to reservoir at thermodynamic equilibrium.Comment: 24 pages (new version), accepted for publication in Physica
Berry's Phase in the Presence of a Dissipative Medium
We consider the spin 1/2 model coupled to a slowly varying magnetic field in
the presence of a weak damping represented by a Lindblad-form operators. We
show that Berry's geometrical phase remains unaltered by the two dissipation
mechanism considered. Dissipation effects are twofold: a shrinking in the
modulus of the Bloch's vector, which characterizes coherence loss and a time
dependent (dissipation related) precession angle. We show that the line
broadening of the Fourier transformation of the components of magnetization is
only due to the presence of dissipation.Comment: 19 pages, 2 figure
Evolution and morphology of 2d chiral structures of quinoline derivatives at the air-water interface
Folding of cytosine-based nucleolipid monolayer by guanine recognition at the air-water interface
Monolayers of a cytosine-based nucleolipid (1,2-dipalmitoyl-sn-glycero-3-(cytidine diphosphate) (ammonium salt), CDP-DG) at basic subphase have been prepared at the air-water interface both in absence and presence of guanine. The formation of the complementary base pairing is demonstrated by combining surface experimental techniques, i.e., surface pressure (π)–area (A), Brewster angle microscopy (BAM), infrared spectroscopy (PM-IRRAS) and computer simulations. A folding of the cytosine-based nucleolipid molecules forming monolayer at the air-water interface occurs during the guanine recognition as absorbate host and is kept during several compression-expansion processes under set experimental conditions. The specificity between nitrogenous bases has been also registered. Finally, mixed monolayers of CDP-DG and a phospholipid (1,2-dimyristoyl-sn-glycero-3-phosphate (sodium salt), DMPA) has been studied and a molecular segregation of the DMPA molecules has been inferred by the additivity rule
Surface-Active Fluorinated Quantum Dots for Enhanced Cellular Uptake
Fluorescent nanoparticles, such as quantum dots, hold great potential for biomedical applications,
mainly sensing and bioimaging. However, the inefficient cell uptake of some nanoparticles hampers their application in clinical practice. Here, the effect of the modification of the quantum dot surface with fluorinated ligands to increase their surface activity and, thus, enhance their cellular uptake was explored
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