The Physics of Liquid Para-Hydrogen

Macroscopic systems of hydrogen molecules exhibit a rich thermodynamic phase behavior. Due to the simplicity of the molecular constituents a detailed exploration of the thermal properties of these boson systems at low temperatures is of fundamental interest. Here,we report theoretical and experimental results on various spatial correlation functions and corresponding distributions in momentum space of liquid para-hydrogen close to the triple point. They characterize the structure of the correlated liquid and provide information on quantum effects present in this Bose fluid. Numerical calculations employ Correlated Density-Matrix(CDM)theory and Path-Integral Monte-Carlo(PIMC)simulations. A comparison of these theoretical results demonstrates the accuracy of CDM theory. This algorithm therefore permits a fast and efficient quantitative analysis of the normal phase of liquid para-hydrogen.We compare and discuss the theoretical results with available experimental data.Comment: 14 pages, 7 figure

Attitudes and motivation in SLA among Hispanics in New York City.

Sin resumenThe purpose of this study is on the one hand, to describe the attitudes and motivation in Second Language Acquisition (SLA) among I-lispanic inmigrants in New York. On the other hand, to point out possible causes why the individuals questioned did not speak English after baving lived in the US br many years. Conclusions are drawn concerning which attitudes lead to motivation and which ones hinder leaming the target language. Didáctica, 9,95-118. Servicio de Publicaciones UCM. Madrid, 1997 96 M. "Luisa Go,-cía Bermejo M. " Guadalupe Villarreal Giteva`a

Breathe: respiratory health and disability

The December issue of Breathe looks at respiratory health in people with disabilities http://ow.ly/Vn9y305KcL

Implanted muon spin spectroscopy on 2-O-adamantane: a model system that mimics the liquid

The transition taking place between two metastable phases in 2-O-adamantane, namely the [Formula: see text] cubic, rotator phase and the lower temperature P21/c, Z  =  4 substitutionally disordered crystal is studied by means of muon spin rotation and relaxation techniques. Measurements carried out under zero, weak transverse and longitudinal fields reveal a temperature dependence of the relaxation parameters strikingly similar to those exhibited by structural glass[Formula: see text]liquid transitions (Bermejo et al 2004 Phys. Rev. B 70 214202; Cabrillo et al 2003 Phys. Rev. B 67 184201). The observed behaviour manifests itself as a square root singularity in the relaxation rates pointing towards some critical temperature which for amorphous systems is located some tens of degrees above that shown as the characteristic transition temperature if studied by thermodynamic means. The implications of such findings in the context of current theoretical approaches concerning the canonical liquid-glass transition are discussed.Postprint (author's final draft

EFFECT OF AGE ON HIGH JUMP TAKEOFF BIOMECHANICS

The aim of the study was to analyse the differences in critical features of high jump take-off in different ages. 3D photogrammetry was used to analyse the best jump of the participants of 3 Spanish Indoor Championships (2009) (13-15 y, 17-18 y, and 18-34 y). The variables measured were horizontal velocity of the centre of mass (CM) at touchdown (VH0), knee angle at touchdown (K0), leg angle at touchdown (L0); height of the CM at touchdown (H0); and take-off angle (TOA). The three groups were compared with ANOVA and each variable was correlated with the maximum CM height. Statistical differences were found in VH0 and H0, but not in the variables directly related to the take-off technique. It is concluded that younger athletes use similar techniques than older ones. This might be a wrong strategy, as they should adapt it to their maturity limitations

Quantum Langevin equations for a two-mode parametric amplifier: Noise squeezing without negative diffusion

13 págs.; 5 figs,; PACS number(s): 42.50.Dv, 42.50.KbThe theory of a two-mode nondegenerate parametric amplifier in a cavity is reformulated in terms of quadrature-phase-amplitude variables. The corrrespondence with a genuine classical stochastic linear process is found (non-negative-definite diffusion matrices) for the case of a cavity device immersed in thermal or ordinary (nonsqueezed) vacuum sources. A special kind of squeezing, i.e., quadrature squeezing [B. L. Schumaker, Phys. Rep. 135, 318 (1986)], is found to be characteristic of the internal steady state for the case of a cavity model subjected to an additional phase-sensitive noise source coupled to one of the two internal modes. Finally, the usual squeezing spectrum of the output field is calculated in both cases by means of an input-output formalism based upon a symmetric ordering scheme of noncommuting operators, well adapted for the quadrature-phase description of the fields involved in the interaction. © 1992 The American Physical Society.Work supported in part by Grants No. TIC90-80, from DGICYT (Spain), and No. A-91002002-15, from U.P.M. (Madrid, Spain).Peer Reviewe

Contribution to phaneroptical study in andalusian hound dog breed

We have studied the type of hair and the coat colour of the Andalusian Hound breed with a view to characterise and typify the nine varieties recognised in the racial pattern. We have concluded the existence of highly significant differences between sizes for the variables type of hair and coat colour, what it is confirming the present reproductive separation and isolation of each variety in the management of the breed book. At the same time we have developed a study of the variable related to the mouth form obtaining the majority of the animal presenting correct mouth caught, but the defect prognatism appear in all the varieties, while the enogmatism only appear in the medium size varieties.Se estudia el tipo de pelo y la coloración de la capa dentro de la raza Podenco Andaluz con vistas a conseguir la caracterización y tipificación de las nueve variedades reconocidas en su patrón racial. Se concluye la existencia de diferencias altamente significativas entre la variable talla y las variables tipo de pelo y color de la capa lo que confirma el actual tratamiento en la separación y aislamiento reproductivo en cada una de las variedades dentro de la gestión de los registros genealógicos de la raza. Asimismo se realiza un estudio de las variables fanerópticas de la boca obteniendo una mayoría de animales que presentan un tipo de mordidas correctas si bien el defecto de mordida prognata está presente en todas las variedades mientras que el enogmatismo sólo aparece en las correspondientes a la talla media

Consideraciones didácticas sobre la enseñanza de lenguas extranjeras asistida por ordenador.

El desarrollo de las nuevas tecnologías en las últimas décadas nos ha impulsado a reflexionar sobre las posibilidades que la tecnología multimedia puede aportar a la enseñanza de la lengua extranjera, con sus ventajas y limitaciones. Partiendo de la evolución de los distintos enfoques en este campo, examinamos algunos programas actuales en CD-ROM y evaluamos sus diferentes actividades y contenidos. También consideramos de qué manera Internet está cambiando la concepción de la enseñanza y el papel del profesor y del alumno

Non-Normality as a Predictor of Participation in Bullying: Valuation in Victims and Aggressors

Bullying is related to several variables, including diversity and variables that place the victim outside of normality. However, it is not easy to find a single meaning of normality. The present study has two main objectives: to find out whether victims are evaluated as non-normal and to find out whether aggressors are evaluated as non-normal. A cross-sectional, correlational, and quantitative study was designed, focusing on a representative sample of secondary school students from the Community of Madrid. The sample consisted of 2076 participants and was constructed using a stratified, proportional, and random sampling technique. To gather this information, a questionnaire was constructed. It includes a first section where sociodemographic and normality information is collected, and a second section made up of the Defensor del pueblo-UNICEF Bullying Questionnaire. The reliability and consistency of the questionnaire are acceptable (Cronbach’s alpha 0.91). For the comparison of means between groups, a Student’s t-test was applied, and the correlation between variables was calculated by applying the bivariate correlation test. Results show that victims are evaluated as non-normal while aggressors are perceived as normal. This implies that the risk of being involved in bullying situations as a victim can be predicted. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Thermal study of a transport container

A thermal study of a container for international transport has been carried out in order to determine the temperature distributions. Several experimental conditions such as cooling modes, the onset of defrosting, the existence of cargo inside the container and two varying set points have been evaluated. It was observed that the difference between the temperature inside the container and the set point raised up to 30% of ambient temperature. Moreover, it was observed that the modulated cooling allowed to obtain a more homogeneous refrigeration. However, temperature differences up to 8 °C were observed under on–off control cooling