Gender Differences in Response to a School-Based Mindfulness Training Intervention for Early Adolescents

Mindfulness training has been used to improve emotional wellbeing in early adolescents. However, little is known about treatment outcome moderators, or individual differences that may differentially impact responses to treatment. The current study focused on gender as a potential moderator for affective outcomes in response to school-based mindfulness training. Sixth grade students (N = 100) were randomly assigned to either the six weeks of mindfulness meditation or the active control group as part of a history class curriculum. Participants in the mindfulness meditation group completed short mindfulness meditation sessions four to five times per week, in addition to didactic instruction (Asian history). The control group received matched experiential activity in addition to didactic instruction (African history) from the same teacher with no meditation component. Self-reported measures of emotional wellbeing/affect, mindfulness, and self-compassion were obtained at pre and post intervention. Meditators reported greater improvement in emotional wellbeing compared to those in the control group. Importantly, gender differences were detected, such that female meditators reported greater increases in positive affect compared to females in the control group, whereas male meditators and control males displayed equivalent gains. Uniquely among females but not males, increases in self-reported self-compassion were associated with improvements in affect. These findings support the efficacy of school-based mindfulness interventions, and interventions tailored to accommodate distinct developmental needs of female and male adolescents

Comparison of Predicted and Experimental Behaviour of RC Slabs Subjected to Blast using SDOF Analysis

Explosions emanating from terrorist attacks or military weapons cause damage to civilian and military facilities. Understanding the mechanical behaviour of reinforced concrete structures subjected to blast is of paramount importance for minimizing the possible blast damage. A full-scale experimental program consisting of six reinforced concrete slabs with compressive strengths of 60 MPa, 50 MPa and 40 MPa, measuring 1.0 m × 1.0 m × 0.08 m, and subjected to 2.7 kg of non-confined plastic bonded explosive, was conducted in blast test area of Science and Technology Aerospace Department (Brazilian Air Force). This paper compares experimentally measured peak displacement values with theoretical values. Theoretical analysis was carried out using single degree of freedom (SDOF) models. The comparison showed that SDOF analysis worked very well in predicting the reinforced concrete slab peak displacement against blast effects. Qualitative analysis after the experiments showed that the blast wave shape generated by the cylindrical explosive was not uniformly distributed on the slabs for the standoff distance of 0.927 m∕kg1/3

Internal kinematics of spiral galaxies in distant clusters III. Velocity fields from FORS2/MXU spectroscopy

(Abridged) We study the impact of cluster environment on the evolution of spiral galaxies by examining their structure and kinematics. Rather than two-dimensional rotation curves, we observe complete velocity fields by placing three adjacent and parallel FORS2 MXU slits on each object, yielding several emission and absorption lines. The gas velocity fields are reconstructed and decomposed into circular rotation and irregular motions using kinemetry. To quantify irregularities in the gas kinematics, we define three parameters: sigma_{PA} (standard deviation of the kinematic position angle), Delta phi (the average misalignment between kinematic and photometric position angles) and k_{3,5} (squared sum of the higher order Fourier terms). Using local, undistorted galaxies from SINGS, these can be used to establish the regularity of the gas velocity fields. Here we present the analysis of 22 distant galaxies in the MS0451.6-0305 field with 11 members at z=0.54. In this sample we find both field (4 out of 8) and cluster (3 out of 4) galaxies with velocity fields that are both irregular and asymmetric. We show that these fractions are underestimates of the actual number of galaxies with irregular velocity fields. The values of the (ir)regularity parameters for cluster galaxies are not very different from those of the field galaxies, implying that there are isolated field galaxies that are as distorted as the cluster members. None of the deviations in our small sample correlate with photometric/structural properties like luminosity or disk scale length in a significant way. Our 3D-spectroscopic method successfully maps the velocity field of distant galaxies, enabling the importance and efficiency of cluster specific interactions to be assessed quantitatively.Comment: accepted for publication in A&A, high resolution version available at http://www.astro.rug.nl/~kutdemir/papers

Efficiency of natural clay and titania P25 composites in the decolouring of methylene blue (MB) from aqueous solutions: dual adsorption and photocatalytic processes

In this paper, we use Tunisian clay materials as alternative low-cost adsorbents, as well as substrates to immobilise TiO2 for the decolouration of methylene blue (MB) dye solutions. The collected raw clay from the mine of Tamra was characterised by various techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray fluorescence (XRF). XRD patterns of the raw clay showed halloysite as the main phase (61%), with a lower content of kaolinite (39%). For MB adsorption, the experimental data were fitted by Langmuir and Freundlich adsorption equations. It was found that the studied clays alone were not very efficient at adsorbing MB dye molecules. The decolouration of MB was improved by adding a photocatalytic function to the clay, by adding various amounts of TiO2 nanopowder (20–80 wt%) to the clay, imbuing it with photocatalytic capabilities. These combined effects of the phenomena of adsorption and photocatalysis for MB removal by the TiO2-doped clay resulted in a very satisfactory performance, even with the relatively low quantity of 20 wt% added TiO2 photocatalyst. This gave 48.6% removal after only 30-min adsorption in the dark, increasing to 84.1% removal after a further 3 h under UV light, through combined chemo-physical adsorption and photocatalytic decolouration phenomena

Divergência genético-morfológica entre acessos de feijão caupi de porte semi-ereto e ereto.

O estudo da divergência é essencial para o melhoramento vegetal, pois possibilita a quantificação da variabilidade genética..

Biometria de frutos em um plantio de açaí em Porto Velho, Rondônia.

O objetivo deste trabalho foi realizar a biometria de frutos em um plantio de açaí em Porto Velho, Rondônia

Radial stability analysis of the continuous pressure gravastar

Radial stability of the continuous pressure gravastar is studied using the conventional Chandrasekhar method. The equation of state for the static gravastar solutions is derived and Einstein equations for small perturbations around the equilibrium are solved as an eigenvalue problem for radial pulsations. Within the model there exist a set of parameters leading to a stable fundamental mode, thus proving radial stability of the continuous pressure gravastar. It is also shown that the central energy density possesses an extremum in rho_c(R) curve which represents a splitting point between stable and unstable gravastar configurations. As such the rho_c(R) curve for the gravastar mimics the famous M(R) curve for a polytrope. Together with the former axial stability calculations this work completes the stability problem of the continuous pressure gravastar.Comment: 17 pages, 5 figures, References corrected, minor changes wrt v1, matches published versio

Magnetic Fields of Spherical Compact Stars in Braneworld

We study the dipolar magnetic field configuration in dependence on brane tension and present solutions of Maxwell equations in the internal and external background spacetime of a magnetized spherical star in a Randall-Sundrum II type braneworld. The star is modelled as sphere consisting of perfect highly magnetized fluid with infinite conductivity and frozen-in dipolar magnetic field. With respect to solutions for magnetic fields found in the Schwarzschild spacetime brane tension introduces enhancing corrections both to the interior and the exterior magnetic field. These corrections could be relevant for the magnetic fields of magnetized compact objects as pulsars and magnetars and may provide the observational evidence for the brane tension through the modification of formula for magneto-dipolar emission which gives amplification of electromagnetic energy loss up to few orders depending on the value of the brane tension.Comment: 11 pages, 5 figures, 1 tabl

The Effect of Star Formation History on the Inferred Initial Stellar Mass Function

Peaks and lulls in the star formation rate (SFR) over the history of the Galaxy produce plateaux and declines in the present day mass function (PDMF) where the main-sequence lifetime overlaps the age and duration of the SFR variation. These PDMF features can be misinterpreted as the form of the intrinsic stellar initial mass function (IMF) if the star formation rate is assumed to be constant or slowly varying with time. This effect applies to all regions that have formed stars for longer than the age of the most massive stars, including OB associations, star complexes, and especially galactic field stars. Related problems may apply to embedded clusters. Evidence is summarized for temporal SFR variations from parsec scales to entire galaxies, all of which should contribute to inferred IMF distortions. We give examples of various star formation histories to demonstrate the types of false IMF structures that might be seen. These include short-duration bursts, stochastic histories with log-normal amplitude distributions, and oscillating histories with various periods and phases. The inferred IMF should appear steeper than the intrinsic IMF over mass ranges where the stellar lifetimes correspond to times of decreasing SFRs; shallow portions of the inferred IMF correspond to times of increasing SFRs. If field regions are populated by dispersed clusters and defined by their low current SFRs, then they should have steeper inferred IMFs than the clusters. The SFRs required to give the steep field IMFs in the LMC and SMC are determined. Structure observed in several determinations of the Milky Way field star IMF can be accounted for by a stochastic and bursty star formation history.Comment: accepted by ApJ for 1 Jan 2006, Vol 636, 12 pages + 6 figure

The effects of a Variable IMF on the Chemical Evolution of the Galaxy

In this work we explore the effects of adopting an initial mass function (IMF) variable in time on the chemical evolution of the Galaxy. In order to do that we adopt a chemical evolution model which assumes two main infall episodes for the formation of the Galaxy. We study the effects on such a model of different IMFs. First, we use a theoretical one based on the statistical description of the density field arising from random motions in the gas. This IMF is a function of time as it depends on physical conditions of the site of star formation. We also investigate the behaviour of the model predictions using other variable IMFs, parameterized as a function of metallicity. Our results show that the theoretical IMF when applied to our model depends on time but such time variation is important only in the early phases of the Galactic evolution, when the IMF is biased towards massive stars. We also show that the use of an IMF which is a stronger function of time does not lead to a good agreement with the observational constraints suggesting that if the IMF varied this variation should have been small. Our main conclusion is that the G-dwarf metallicity distribution is best explained by infall with a large timescale and a constant IMF, since it is possible to find variable IMFs of the kind studied here, reproducing the G-dwarf metallicity but this worsens the agreement with other observational constraints.Comment: 7 pages, to appear in "The Chemical Evolution of the Milky Way: Stars vs Clusters", Vulcano, September 1999, F. Giovannelli and F. Matteucci eds. (Kluwer, Dordrecht) in pres