Saturated operation of a transient collisional x-ray laser

Saturation of a low pump energy x-ray laser utilizing a transient inversion mechanism on the 3p-3s transition at 32.63 nm in Ne-like Ti has been demonstrated. A close to saturation amplification was simultaneously achieved for the 3d-3p, J=1-->1 transition at 30.15 nm. Small signal effective transient gain coefficients of g similar to 46 and similar to 35 cm(-1) and gain-length products of 16.7 and 16.9 for these lines were obtained. Experiments demonstrate that it is possible to achieve saturated laser action in a transient regime with Ne-like Ti for a pump energy as low as similar to 5 J.

Novel ruthenium-terpyridyl complex for direct oxidation of amines to nitriles

High catalytic activity and selectivity has been demonstrated for the oxidation of both aliphatic and aromatic amines to nitriles under benign conditions with dioxygen or air using the Ru2Cl4(az-tpy)(2) complex. The conversion was found to be strongly influenced by the alkyl chain length of the reactant with shorter chain amines found to have lower conversions than those with longer chains. Importantly, by using the ruthenium terpyridine complex functionalized with azulenyl moiety at the 4 position of central pyridine core provided a much higher reactivity catalyst compared with a series of ruthenium terpyridine-based ligand complexes reported. Mechanistic studies using deuterated benzylamine demonstrated the importance of RuOH in this reaction.

Prevención de drogodependencias : intervención educativa versus comportamental.

Comprobar la eficacia de un programa de aprendizaje estructurado de habilidades sociales frente a otro de formación-cambio de actitud más enmarcado en la corriente pedagógica, frente a la no intervención en alumnos de séptimo curso de EGB. 71 alumnos (39 varones y 32 mujeres) de séptimo curso de EGB pertenecientes al colegio público La Paz de Callosa del Segura (Alicante) cuyas edades escilaban entre los 11 y 13 años. La intervención duró un mes, se distribuyeron al azar los grupos experimentales (dos) y el de control. El grupo experimental I, contó con 23 alumnos (intervención educativa), el grupo experimental II, con 24 (intervención comportamental) y el grupo de control con 24 alumnos. Cada grupo se dividió en dos para que el grupo de sujetos a intervenir fuera lo más reducido posible y la intervención provechosa. Evaluación antes y después del tratamiento. El programa pedagógico constó de ocho temas y se aplicó en 8 sesiones (grupo I) y el entrenamiento en habilidades sociales (grupo II) se realizó en 9 sesiones, constando de 9 tipos de habilidades. Cuestionario de Información para evaluar el nivel de conocimientos de los sujetos sobre tabaco, alcohol y otras drogas (cuestionario reforzado de Maciá, 1986), Cuestionario de Hábitos de Consumo de distintos tipos de drogas (tabaco, alcohol, fármacos), Cuestionario de Actitudes, Escala de Actitud tipo Lickert, Cuestionario de Habilidades Sociales (derivado de la Escala de Asertividad de Rathus, 1980), Sistema de Evaluación Conductual de la Habilidad Social (SECHS, de Caballo, 1988), Cuestionario de Alternativas de Tiempo Libre (elaboración propia). La información general sobre drogas se ve mejorada tras el tratamiento, el grupo II destaca por encima del I y el de control en las actitudes ante las drogas. El grupo II obtiene la medida más alta en el cuestionario de habilidades sociales, en el SECHS y en las alternativas de ocio, los sujetos del grupo II se muestran más interesados en realizar más actividades en su tiempo libre. Se puede apreciar una superioridad en la Intervención Comportamental respecto a la educativa en cuanto a efectividad, en cualquier caso, tratándose de intervenciones complementarias, se sugiere su aplicación conjunta como dos fases del mismo programa de prevención del consumo de drogas, dedicando el tiempo necesario a profundizar en cada una de ellas, para posteriores investigaciones.

Termografia digital por infravermelho do escroto e qualidade do sêmen em touros nelore (bos taurus indicus)

Aimed to study the relationship between scrotal temperature on semen quality by use of infrared thermography in Nelore bulls bred extensively. There were scrotal thermography and semen collection. Climatic data were collected by means of globe thermometer. The thermograms of the scrotum were obtained by digital infrared thermography. We carried out ejaculates through electroejaculation for analysis of quantitative and qualitative characteristics. For the data, we used analysis of variance and subsequently applied the Tukey test at 5%. (p <0.05) between animals for sperm vigor, sperm motility between animals and between crops, sperm concentration, total sperm and total viable sperm between groups, between harvests for the scrotum temperatures and climate data. It was concluded that the surface temperatures of the scrotum and climatic factors influence the quality of semen. Thermography is recommended as a complementary test in the evaluation of reproductive bulls.

Theoretical models of planetary system formation: mass vs. semi-major axis

Context. Planet formation models have been developed during the past years to try to reproduce what has been observed of both the solar system and the extrasolar planets. Some of these models have partially succeeded, but they focus on massive planets and, for the sake of simplicity, exclude planets belonging to planetary systems. However, more and more planets are now found in planetary systems. This tendency, which is a result of radial velocity, transit, and direct imaging surveys, seems to be even more pronounced for low-mass planets. These new observations require improving planet formation models, including new physics, and considering the formation of systems. Aims: In a recent series of papers, we have presented some improvements in the physics of our models, focussing in particular on the internal structure of forming planets, and on the computation of the excitation state of planetesimals and their resulting accretion rate. In this paper, we focus on the concurrent effect of the formation of more than one planet in the same protoplanetary disc and show the effect, in terms of architecture and composition of this multiplicity. Methods: We used an N-body calculation including collision detection to compute the orbital evolution of a planetary system. Moreover, we describe the effect of competition for accretion of gas and solids, as well as the effect of gravitational interactions between planets. Results: We show that the masses and semi-major axes of planets are modified by both the effect of competition and gravitational interactions. We also present the effect of the assumed number of forming planets in the same system (a free parameter of the model), as well as the effect of the inclination and eccentricity damping. We find that the fraction of ejected planets increases from nearly 0 to 8% as we change the number of embryos we seed the system with from 2 to 20 planetary embryos. Moreover, our calculations show that, when considering planets more massive than ~5 M⊕, simulations with 10 or 20 planetary embryos statistically give the same results in terms of mass function and period distribution.

Always looking on the bright side of life? : Exploring optimism and health in three UK post-industrial urban settings

The survey was jointly funded by NHS Health Scotland and the Glasgow Centre for Population Health.

Always looking on the bright side of life? : Exploring optimism and health in three UK post-industrial urban settings

The survey was jointly funded by NHS Health Scotland and the Glasgow Centre for Population Health.

Always looking on the bright side of life? : Exploring optimism and health in three UK post-industrial urban settings

The survey was jointly funded by NHS Health Scotland and the Glasgow Centre for Population Health.

The VLT-FLAMES tarantula survey:X. Evidence for a bimodal distribution of rotational velocities for the single early B-type stars

Aims. Projected rotational velocities (ve sin i) have been estimated for 334 targets in the VLT-FLAMES Tarantula Survey that do not manifest significant radial velocity variations and are not supergiants. They have spectral types from approximately O9.5 to B3. The estimates have been analysed to infer the underlying rotational velocity distribution, which is critical for understanding the evolution of massive stars. Methods. Projected rotational velocities were deduced from the Fourier transforms of spectral lines, with upper limits also being obtained from profile fitting. For the narrower lined stars, metal and non-diffuse helium lines were adopted, and for the broader lined stars, both non-diffuse and diffuse helium lines; the estimates obtained using the different sets of lines are in good agreement. The uncertainty in the mean estimates is typically 4% for most targets. The iterative deconvolution procedure of Lucy has been used to deduce the probability density distribution of the rotational velocities. Results. Projected rotational velocities range up to approximately 450 kms-1 and show a bi-modal structure. This is also present in the inferred rotational velocity distribution with 25% of the sample having 0 <ve <100 km s^-1 and the high velocity component having v_e ∼ 250 km s^-1. There is no evidence from the spatial and radial velocity distributions of the two components that they represent either field and cluster populations or different episodes of star formation. Be-type stars have also been identified. Conclusions. The bi-modal rotational velocity distribution in our sample resembles that found for late-B and early-A type stars.While magnetic braking appears to be a possible mechanism for producing the low-velocity component, we can not rule out alternative explanations. © ESO 2013.