207 research outputs found
Sexo, sexismo y acoso escolar entre iguales
This research approaches the study of the relationship, first between sex and sexism, and then between these two variables and bullying. This study could show that boys are more involved in bullying situations more because of their sexist beliefs than for the biological fact of to be a boy.El presente trabajo aborda el estudio de la relación, primero, entre sexo y sexismo, y después entre estas dos variables y las conductas de acoso escolar entres iguales. Este estudio parece apuntar en la dirección de que los chicos participan con más frecuencia en situaciones de acoso escolar, más que por el hecho biológico de ser chicos, por sus creencias sexistas
Sex, Sexism and bullying
This research approaches the study of the relationship, first between sex and sexism, and then between these two variables and bullying. This study could show that boys are more involved in bullying situations more because of their sexist beliefs than for the biological fact of to be a boy.</span
Quantum advantage from energy measurements of many-body quantum systems
The problem of sampling outputs of quantum circuits has been proposed as a
candidate for demonstrating a quantum computational advantage (sometimes
referred to as quantum "supremacy"). In this work, we investigate whether
quantum advantage demonstrations can be achieved for more physically-motivated
sampling problems, related to measurements of physical observables. We focus on
the problem of sampling the outcomes of an energy measurement, performed on a
simple-to-prepare product quantum state -- a problem we refer to as energy
sampling. For different regimes of measurement resolution and measurement
errors, we provide complexity theoretic arguments showing that the existence of
efficient classical algorithms for energy sampling is unlikely. In particular,
we describe a family of Hamiltonians with nearest-neighbour interactions on a
2D lattice that can be efficiently measured with high resolution using a
quantum circuit of commuting gates (IQP circuit), whereas an efficient
classical simulation of this process should be impossible. In this high
resolution regime, which can only be achieved for Hamiltonians that can be
exponentially fast-forwarded, it is possible to use current theoretical tools
tying quantum advantage statements to a polynomial-hierarchy collapse whereas
for lower resolution measurements such arguments fail. Nevertheless, we show
that efficient classical algorithms for low-resolution energy sampling can
still be ruled out if we assume that quantum computers are strictly more
powerful than classical ones. We believe our work brings a new perspective to
the problem of demonstrating quantum advantage and leads to interesting new
questions in Hamiltonian complexity.Comment: Comments are welcom
Strategies to enhance properties of 3D-printed ceramics
Technologies of additive manufacturing (AM) impress with the ability of fabricating ceramic parts of high precision and complexity. However, their mechanical performance may be affected by printing process-related parameters as compared to conventionally processed ceramics. To improve strength and damage tolerance of 3D-printed alumina-based ceramics, two different approaches have been investigated, focusing on microstructural and architectural design. (i) High strength alumina based on a multilayer design: A-B-A laminates of (A) alumina and (B) alumina-zirconia materials were additive manufactured using the 2K-lithography-based ceramic manufacturing (LCM) technology. Through mismatching thermal expansions of the different materials, compressive residual stresses were induced into the surface alumina layers during cooling after sintering. A biaxial strength of 1 GPa was obtained, in comparison to 650 MPa on 3D-printed bulk alumina.[1] (ii) Damage tolerance alumina: Textured alumina ceramics were 3D-printed by applying the method of templated grain growth. Through shear forces, occurring during the printing process, aligned high aspect ratio templates grew due to the dissolution and precipitation of surrounding submicron-sized powder particles. As a result, anisotropic crystallographic properties as well as the morphology of the textured grains led to a biaxial strength of 670 MPa, compared to 570 MPa measured on equiaxed alumina sintered under the same conditions. Additionally, toughening mechanisms as crack deflection, bifurcation and even crack arrest could be observed, leading to an enhanced damage tolerance.[2] These two strategies may be applied to other 3D-printed ceramic materials and systems of more complex geometry to enhance their structural properties
Aproximación al concepto de emocionalidad. El estereotipo emocional del sexismo || Approach to the concept of emotionality. The emotional stereotype of sexism
This work has two main objectives: The first one is to understand the emotional stereotype of sexism, or what is the same, to know the expectations and beliefs that sexism shows about what should be the emotional behavior in women and men from this ideological position. The second objective is to propose a first approach and definition of the emotional dimension of sexism within the framework of the theory of Ambivalent Sexism, that we will call emotionality. For the development of this work we have selected a sample of 1608 students located on the four provinces and five Education Faculties from Castilla La Mancha. 1308 participants are those who have fulfilled all the conditions to join the study. The results show that sexism presents a stereotype of emotional management very clear and different for men and women as well as complementary as sexist ideology itself, where women get their highest score in emotional care and its lowest score in emotional regulation. By contrast, men get the highest score in emotional regulation and its lowest score in emotional care. This sexist emotional stereotype is also significantly different, from our results perspective, of the stereotype of study population that has not sexist beliefs. Our results suggest, therefore, the existence of this sexist emotional stereotype and the need to include a new dimension, the emotionality, in the definition of sexism.Este trabajo persigue dos objetivos fundamentales: El primer objetivo es conocer el estereotipo emocional del sexismo, o lo que es igual, las expectativas y creencias que el sexismo tiene acerca de lo que debe ser el comportamiento emocional en mujeres y hombres desde esta posición ideológica. El segundo objetivo es proponer una primera aproximación y definición de la dimensión emocional del sexismo en el marco de la teoría del sexismo ambivalente, a la que llamamos Emocionalidad. Para el desarrollo de este trabajo se ha seleccionado una muestra de 1608 estudiantes de Magisterio de la comunidad de Castilla la Mancha, repartidos en las cuatro provincias y los cinco campus con Facultad de Educación. Han sido 1308 participantes los que han cumplido todas las condiciones para poder formar parte del estudio. Los resultados muestran que el sexismo presenta un estereotipo de gestión emocional muy claro y diferente para hombres y mujeres, además de complementario según la propia ideología sexista, donde las mujeres obtienen su puntuación más alta en atención emocional y su puntuación más baja en regulación emocional. Por el contrario, los hombres obtienen su puntuación más alta en regulación emocional y su puntuación más baja en atención emocional. Este estereotipo emocional sexista es, además, significativamente diferente según nuestros resultados al que presenta la población estudiada no sexista. Nuestros resultados apuntan, por tanto, a la existencia de este estereotipo emocional sexista y a la necesidad de incluir la dimensión emocional, la emocionalidad, en la definición de sexismo
Mosses as an integrating tool for monitoring PAH atmospheric deposition: Comparison with total deposition and evaluation of bioconcentration factors. A year-long case-study
Polycyclic aromatic hydrocarbon (PAH) atmospheric deposition was evaluated at a remote site in Northern Spain using moss biomonitoring with Hylocomium splendens (Hedw.) Schimp., and by measuring the total deposition fluxes of PAHs. The year-long study allowed seasonal variations of PAH content in mosses to be observed, and these followed a similar trend to those of PAH fluxes in total deposition. Generally, atmospheric deposition of PAHs is greater in winter than in summer, due to more PAH emissions from domestic heating, less photoreactivity of the compounds, and intense leaching of the atmosphere by wet deposition. However, fractionation of these molecules between the environmental compartments occurs: PAH fluxes in total deposition and PAH concentrations in mosses are correlated with their solubility (r=0.852, p<0.01) and lipophilic properties (KOW, r=0.768, p<0.01), respectively. This annual study therefore showed that atmospheric PAH fluxes can be estimated with moss biomonitoring data if the bioconcentration or ‘enriching’ factors are known
Drug absorption through a cell monolayer: a theoretical work on a non-linear three-compartment model
The subject of analysis is a non-linear three-compartment model, widely used
in pharmacological absorption studies. It has been transformed into a general
form, thus leading automatically to an appropriate approximation. This made the
absorption profile accessible and expressions for absorption times, apparent
permeabilities and equilibrium values were given. These findings allowed a
profound analysis of results from non-linear curve fits and delivered the
dependencies on the systems' parameters over a wide range of values. The
results were applied to an absorption experiment with multidrug
transporter-affected antibiotic CNV97100 on Caco-2 cell monolayers.Comment: 21 pages, 8 figures (v4: detailed definition of the treated model -
additional information about limitations
Residual stresses in Al2O3-ZrO2 multilayered ceramics: nature, evaluation and influence on the structural integrity
[ES] El presente trabajo comprende el diseño y procesamiento por colaje de suspensiones de sistemas multicapa basados en
capas gruesas de alúmina y capas finas de alúmina-circona. Durante el enfriamiento desde la temperatura de sinterización
se generan tensiones residuales en las capas debido a la expansión asociada a la transformación martensítica de la circona.
En esta investigación se estudian los parámetros de procesamiento para la fabricación de estos sistemas laminados y se
caracterizan microestructuralmente las capas que lo componen. Como resultado se obtienen multicapas cerámicas con
diferente relación de espesores entre capas adyacentes utilizando como método de control las cinéticas de colaje de los
correspondientes monolíticos. Adicionalmente, se determinan analíticamente las tensiones residuales generadas en los
laminados por medio de las diferencias volumétricas determinadas en ensayos dilatométricos y del módulo elástico de cada
capa. Se encuentra que en las capas delgadas se desarrollan elevadas tensiones de compresión mientras que en las gruesas
se inducen tensiones residuales de tracción. El efecto de estas tensiones sobre la integridad mecánica del material se discute
en términos de las observaciones de fenómenos de fisuración intrínseca: tanto de grietas de borde o “edge cracks” en la
superficie libre de las capas delgadas como de fisuras túnel o “tunneling cracks” en las capas gruesas.[EN] This work studies the design and processing by slip casting of multilayered systems based on thick alumina and thin aluminazirconia
layers. During cooling from the sintering temperature residual stresses may arise due to expansion associated to
the martensitic transformation of the zirconia. In this investigation, the processing parameters involved in the fabrication of
theses layered systems are studied and the respective layers microstructurally characterized. As a result, several multilayered
ceramics in terms of thickness ratio between adjacent layers are obtained by means of the casting kinetics of the corresponding
monoliths. Additionally, the residual stresses generated in the laminates are analytically determined through the difference
in shrinkage assessed with dilatometric tests and the elastic modulus corresponding to each layer. It is found that in the thin
layers elevated residual compressive stresses are generated whilst in the thick ones tensile residual stresses are induced.
The effect of these stresses on the mechanical integrity of the material is discussed in terms of the observations of intrinsic
cracking phenomena: both edge cracks at the free surface of the thin layers and tunneling cracks in the thick layers.El presente trabajo ha sido financiado por el Ministerio de Ciencia y Tecnología (MCYT) en el marco del proyecto Nº MAT2002-00368, así como por el programa de la Comunidad Europea bajo el contrato HPRN-CT-2002-00203, [SICMAC].Peer reviewe
Squeezing resulting from a fourth-order interaction in a degenerate parametric amplifier with absorption losses
7 págs.; 8 figs.The squeezing properties of a model of a degenerate parametric amplifier with absorption losses and an added fourth-order nonlinearity have been analyzed. The approach used consists of obtaining the Langevin equation for the optical field from the Heisenberg equation provided that a linearization procedure is valid. The steady states of the deterministic equations have been obtained and their local stability has been analyzed. The stationary covariance matrix has been calculated below and above threshold. Below threshold, a squeezed vacuum state is obtained and the nonlinear effects in the fluctuations have been taken into account by a Gaussian decoupling. In the case above threshold, a phase-squeezed coherent state is obtained and numerical simulations allowed to compute the time interval, depending on the loss parameter, on which the system jumps from one stable state to the other. Finally, the variances numerically determined have been compared with those obtained from the linearized theory and the limits of validity of the linear theory have been analyzed. It has become clear that the nonlinear contribution may perhaps be profitably used for the construction of above-threshold squeezing devices. © 1991 The American Physical Society.Peer Reviewe
High resolution infrared and Raman spectra of 13C12CD2: The CD stretching fundamentals and associated combination and hot bands
11 pags.; 4 figs.; 9 tabs.© 2015 AIP Publishing LLC. Infrared and Raman spectra of mono 13C fully deuterated acetylene, 13C12CD2, have been recorded and analysed to obtain detailed information on the C—D stretching fundamentals and associated combination, overtone, and hot bands. Infrared spectra were recorded at an instrumental resolution ranging between 0.006 and 0.01 cm−1 in the region 1800–7800 cm−1. Sixty new bands involving the ν 1 and ν 3 C—D stretching modes also associated with the ν 4 and ν 5 bending vibrations have been observed and analysed. In total, 5881 transitions have been assigned in the investigated spectral region. In addition, the Q branch of the ν 1 fundamental was recorded using inverse Raman spectroscopy, with an instrumental resolution of about 0.003 cm−1. The transitions relative to each stretching mode, i.e., the fundamental band, its first overtone, and associated hot and combination bands involving bending states with υ 4 + υ 5 up to 2 were fitted simultaneously. The usual Hamiltonian appropriate to a linear molecule, including vibration and rotation l-type and the Darling–Dennison interaction between υ 4 = 2 and υ 5 = 2 levels associated with the stretching states, was adopted for the analysis. The standard deviation for each global fit is ≤0.0004 cm−1, of the same order of magnitude of the measurement precision. Slightly improved parameters for the bending and the ν 2 manifold have been also determined. Precise values of spectroscopic parameters deperturbed from the resonance interactions have been obtained. They provide quantitative information on the anharmonic character of the potential energy surface, which can be useful, in addition to those reported in the literature, for the determination of a general anharmonic force field for the molecule. Finally, the obtained values of the Darling–Dennison constants can be valuable for understanding energy flows between independent vibrations.The Bologna authors acknowledge the Università di
Bologna and the financial support of the Ministero dell’
Istruzione dell’Università e della Ricerca (PRIN 2012 “Spettroscopia
e Tecniche computazionali per la ricerca Astrofisica,
atmosferica e Radioastronomica”). D.B. and R.Z.M. acknowledge
the financial support of the Ministry of Economy and
Competitiveness through Research Grant No. FIS2012-38175.Peer Reviewe
- …