Intervención sobre la suma mediante el uso combinado de regletas y TIC’s

Se trata de una investigación empírico-cuantitativa que pretende comprobar que las claves de Driver y Bell (1986) sobre aprendizaje manipulativo y significativo son efectivas para el aprendizaje de la suma en alumnos de 4º de Primaria que presentan dificultades de aprendizaje (Radatz, 1979, 1980). Esta intervención se realizó en el último semestre del curso 2014/2015 en el colegio de la Asunción de Ponferrada. El grupo-clase está formado por 25 alumnos (14 niñas y 11 niños) de 4º de Primaria en donde se aprecia en general déficit de atención, acentuado en tres alumnos, uno de ellos diagnosticado

Harvesting Thermal Fluctuations: Activation Process Induced by a Nonlinear Chain in Thermal Equilibrium

We present a model in which the immediate environment of a bistable system is a molecular chain which in turn is connected to a thermal environment of the Langevin form. The molecular chain consists of masses connected by harmonic or by anharmonic springs. The distribution, intensity, and mobility of thermal fluctuations in these chains is strongly dependent on the nature of the springs and leads to different transition dynamics for the activated process. Thus, all else (temperature, damping, coupling parameters between the chain and the bistable system) being the same, the hard chain may provide an environment described as diffusion-limited and more effective in the activation process, while the soft chain may provide an environment described as energy-limited and less effective. The importance of a detailed understanding of the thermal environment toward the understanding of the activation process itself is thus highlighted

Influence of parent's eating attitudes on eating disorders in school adolescents

Objective: To investigate the relationship between parents' cognitive and behavioural dimensions and the risk of eating disorders (ED) in non-clinical adolescents. Methods: From an initial sample of 1,336 boys and girls with a mean age of 11.37, a total of 258 subjects were selected either as being at risk of ED or as controls. These subjects and their parents comprised the sample at T1 and were followed-up 2 years later (T2). We examined disordered eating attitudes, body dissatisfaction (BD), body mass index (BMI) and ED diagnoses in the adolescents at two points in time. We also used the Eating Disorder Inventory-2 to examine the disordered eating attitudes of their parents at T1. Results: The mother's BD, drive for thinness (DT), ineffectiveness and interoceptive awareness, and the father's DT and perfectionism were related to long-term ED. Logistic regression showed that predictors of ED were being female, mother's DT and social insecurity, and adolescent's BD. The BMI was not a predictor in this model. Father's perfectionism was a risk factor of ED. Conclusion: Specific cognitive and behavioural dimensions of ED in both parents can influence the development of an ED in early adolescents. This should be taken into account in the prevention and family oriented treatment of ED

Osteoma osteoide de paleta humeral con síndrome paraarticular

Los autores presentan un caso de osteoma osteoide de paleta humeral. Destacan el problema diagnóstico que plantean los osteomas osteoides yuxta-articulares y la importancia que tiene la tomografía axial computarizada (TAC) para el diagnóstico y localización de la lesión, siendo esto último fundamental para planificar el tratamiento quirúrgico.The authors show an intraarticular osteoid osteoma of the elbow. They emphasize the diagnostic problem that it pos e and the importance of CT Scann to diagnosis and localization of the lesion, being this important to the surgical procedure

Use of quadrupole time-of-flight mass spectrometry for proposal of transformation products of the herbicide bromacil after water chlorination

The herbicide bromacil has been extensively used in the Spanish Mediterranean region, and although plant protection products containing bromacil have been withdrawn by the European Union, this compound is still frequently detected in surface and ground water of this area. However, the fast and complete disappearance of this compound has been observed in water intended for human consumption, after it has been subjected to chlorination. There is a concern about the possible degradation products formed, since they might be present in drinking water and might be hazardous. In this work, the sensitive full-spectrum acquisition, high resolution and exact mass capabilities of hybrid quadrupole time-of-flight (QTOF) mass spectrometry have allowed the discovery and proposal of structures of transformation products (TPs) of bromacil in water subjected to chlorination. Different ground water samples spiked at 0.5 µg/mL were subjected to the conventional chlorination procedure applied to drinking waters, sampling 2-mL aliquots at different time intervals (1, 10 and 30 min). The corresponding non-spiked water was used as control sample in each experiment. Afterwards, 50 μL of the water was directly injected into an ultra-high-pressure liquid chromatography (UHPLC)/electrospray ionization (ESI)-(Q)TOF system. The QTOF instrument enabled the simultaneous recording of two acquisition functions at different collision energies (MSE approach): the low-energy (LE) function, fixed at 4 eV, and the high-energy (HE) function, with a collision energy ramp from 15 to 40 eV. This approach enables the simultaneous acquisition of both parent (deprotonated and protonated molecules) and fragment ions in a single injection. The low mass errors observed for the deprotonated and protonated molecules (detected in LE function) allowed the assignment of a highly probable molecular formula. Fragment ions and neutral losses were investigated in both LE and HE spectra to elucidate the structures of the TPs found. For those compounds that displayed poor fragmentation, product ion scan (MS/MS) experiments were also performed. On processing the data with specialized software (MetaboLynx), four bromacil TPs were detected and their structures were elucidated. To our knowledge, two of them had not previously been reported

Quiste óseo esencial: Resultados del tratamiento mediante punción intracavitaria con corticoides

Se presenta n los resultado s de l tratamient o de treint a quiste s óseo s esenciales mediante punción intracavitaria con acetato de metil-prednisolona. Se ha obtenido una respuesta favorable en el 93% de los casos con curación completa en el 77% de los casos. Estos resultados apoyan que debe ser el tratamiento inicial de elección en este tipo de lesiones.The results of 30 unicameral bone cyst treated by intracavitary injection of methylprednisolone acetate wer e reviewed. Satisfactory respons e was found in 93% of the cases. Complete restoration of bone architecture was observed in 77% of the cases. These results strongly support the local injection of steroids as the primary elective treatment for unicameral bone cyst

Hole Pairs in the Two-Dimensional Hubbard Model

The interactions between holes in the Hubbard model, in the low density, intermediate to strong coupling limit, are investigated. Dressed spin polarons in neighboring sites have an increased kinetic energy and an enhanced hopping rate. Both effects are of the order of the hopping integral and lead to an effective attraction at intermediate couplings. Our results are derived by systematically improving mean field calculations. The method can also be used to derive known properties of isolated spin polarons.Comment: 4 page

Molecular gyroscopes and biological effects of weak ELF magnetic fields

Extremely-low-frequency magnetic fields are known to affect biological systems. In many cases, biological effects display `windows' in biologically effective parameters of the magnetic fields: most dramatic is the fact that relatively intense magnetic fields sometimes do not cause appreciable effect, while smaller fields of the order of 10--100 $\mu$T do. Linear resonant physical processes do not explain frequency windows in this case. Amplitude window phenomena suggest a nonlinear physical mechanism. Such a nonlinear mechanism has been proposed recently to explain those `windows'. It considers quantum-interference effects on protein-bound substrate ions. Magnetic fields cause an interference of ion quantum states and change the probability of ion-protein dissociation. This ion-interference mechanism predicts specific magnetic-field frequency and amplitude windows within which biological effects occur. It agrees with a lot of experiments. However, according to the mechanism, the lifetime $\Gamma^{-1}$ of ion quantum states within a protein cavity should be of unrealistic value, more than 0.01 s for frequency band 10--100 Hz. In this paper, a biophysical mechanism has been proposed that (i) retains the attractive features of the ion interference mechanism and (ii) uses the principles of gyroscopic motion and removes the necessity to postulate large lifetimes. The mechanism considers dynamics of the density matrix of the molecular groups, which are attached to the walls of protein cavities by two covalent bonds, i.e., molecular gyroscopes. Numerical computations have shown almost free rotations of the molecular gyros. The relaxation time due to van der Waals forces was about 0.01 s for the cavity size of 28 angstr\"{o}ms.Comment: 10 pages, 7 figure

Pinning and switching of magnetic moments in bilayer graphene

We examine the magnetic properties of the localized states induced by lattice vacancies in bilayer graphene with an unrestricted Hartree-Fock calculation. We show that with realistic values of the parameters and for experimentally accessible gate voltages we can have a magnetic switching between an unpolarized and a fully polarized system.Comment: 9 pages, 4 figure