A new cosmic microwave background constraint to primordial gravitational waves

Primordial gravitational waves (GWs) with frequencies > 10^{-15} Hz contribute to the radiation density of the Universe at the time of decoupling of the cosmic microwave background (CMB). The effects of this GW background on the CMB and matter power spectra are identical to those due to massless neutrinos, unless the initial density-perturbation amplitude for the gravitational-wave gas is non-adiabatic, as may occur if such GWs are produced during inflation or some post-inflation phase transition. In either case, current observations provide a constraint to the GW amplitude that competes with that from big-bang nucleosynthesis (BBN), although it extends to much lower frequencies (~10^{-15} Hz rather than the ~10^{-10} Hz lower limit from BBN): at 95% confidence-level, Omega_gw h^2 < 6.9 x 10^{-6} for homogeneous (i.e., non-adiabatic) initial conditions. Future CMB experiments, like Planck and CMBPol, should allow sensitivities to Omega_gw h^2 < 1.4 x 10^{-6} and Omega_gw h^2 < 5 x 10^{-7}, respectively.Comment: 5 pages, 2 figures, submitted to Phys. Rev. Let

BLENDING PEDAGOGY AND DIGITAL TECHNOLOGY TO TRANSFORM EDUCATIONAL ENVIRONMENT

This article shows efficacy of competences-oriented education model, representing effectiveness of pedagogy technology and digital tools blending in transforming education while using tutor’s support. In correspondence to contemporary requirements and education system special features, connection between digital education tools and tutor technology contributing to students’ key competences development is determined. The paper contributes to the field by summarizing some theoretical issues and offering implementation suggestions for effectively integrating digital technologies into teaching and learning. The use of digital technologies in educational activities opens up new opportunities, adequate methods for dissemination and management of digital information, development of necessary competencies on the basis of digital literacy, ensuring equitable access for all who wish to obtain necessary knowledge and decision-making skills, ensuring demand for school graduates in the world labor market in situation of digital economy. Innovative technologies become a problem adding difficulties to students’ burden. Tutor becomes an intermediary between students and digital technologies to promote students’ active learning practices; there are not so many students who can appreciate digital learning practices and get the most of it. The role of tutoring in digital literacy promotion is hard to overestimate. Tutor support is a pedagogical activity in individualization of education aimed at identifying and developing students’ educational motives and interests. To form students’ key competencies in education system, it is necessary to supplement traditional education with tools of digital educational technologies, new trends in pedagogies such as tutoring, which is becoming an integral part of modern learning process

Still flat after all these years

The Universe could be spatially flat, positively curved or negatively curved. Each option has been popular at various times, partly affected by an understanding that models tend to evolve away from flatness. The curvature of the Universe is amenable to measurement, through tests such as the determination of the angles of sufficiently large triangles. The angle subtended by the characteristic scale on the Cosmic Microwave sky provides a direct test, which has now been realised through a combination of exquisite results from a number of CMB experiments. After a long and detailed investigation, with many false clues, it seems that the mystery of the curvature of the Universe is now solved. It's an open and shut case: the Universe is flat.Comment: 7 pages, 2 figures, submitted to the Gravity Research Foundation Essay Competition for 200

Three-dimensional matter-wave vortices in optical lattices

We predict the existence of spatially localized nontrivial vortex states of a Bose-Einstein condensate with repulsive atomic interaction confined by a three-dimensional optical lattice. Such vortex-like structures include planar vortices, their co- and counter-rotating bound states, and distinctly three-dimensional non-planar vortex states. We demonstrate numerically that many of these vortex structures are remarkably robust, and therefore can be generated and observed in experiment.Comment: 4 pages, 6 figure

36 Months Survivability And Its Predictors In Patients With Chronic Heart Failure And Decreased Fraction Of Left Ventricular Ejection Depending On Sex

Aim of the work: to compare survivability parameters during 36 months and their predictors among men and women with chronic heart failure and decreased fraction of left ventricular ejection.Materials and methods: the research included 356 patients with CHF (NYHA ІІ –ІV) with decreased LVEF&lt;40 %, 18–75 years old. Using Kaplan-Meier method, there was analyzed the survivability in men and women during 36 months, then there were analyzed independent factors that influenced survivability terms depending on sex using the multiple logistic regression.Results. Our analysis of the survivability of patients with CHF with decreased LVEF demonstrated that the cumulative survival after 3 years of observation was 49 and 51 % for men and women, respectively. The curves of 36 months survivability didn\u27t reliably differ. At the analysis of factors, associated with the bad prognosis, there were observed differences between groups of men and women with CHF. Thus, in men the predictors of 36 month survival were: the thickness of the right ventricle wall, size of the right atrium, end-diastolic volume and end-systolic volume of LV, indices of EDV and ESV of LV, urinary acid level, value of LVEF. In women the predictors of survivability during 3 years were the following parameters: BMI, DM type 2 in an anamnesis, end-diastolic size of LV, end-systolic size of LV, blood glucose level, LVEF.Conclusion. The survivability of men and women with CHF with decreased LVEF during 36 months didn\u27t reliably differ and was 49 and 51 % respectively. But predictors of the lethal outcome in men and women essentially differed during 36 months, and their number is essentially higher in men

Prompt photon yield and v2v_2 coefficient from gluon fusion induced by magnetic field in heavy-ion collision

We compute the production of prompt photons and the $v_2$ harmonic coefficient in relativistic heavy-ion collisions induced by gluon fusion in the presence of an intense magnetic field, during the early stages of the reaction. The calculations take into account several parameters which are relevant to the description of the experimental transverse momentum distribution, and elliptic flow for RHIC and LHC energies. The main imput is the strength of the magnetic field which varies in magnitude from 1 to 3 times the pion mass squared, and allows the gluon fusion that otherwise is forbidden in the absence of the field. The high gluon occupation number and the value of the saturation scale also play an important role in our calculation, as well as a flow velocity and geometrical factors. Our results support the idea that the origin of at least some of the photon excess observed in heavy-ion experiments may arise from magnetic field induced processes, and gives a good description of the experimental data.Comment: 6 pages, 2 figures, conference paper from ISMD 201

Multiplane 3D superresolution optical fluctuation imaging

By switching fluorophores on and off in either a deterministic or a stochastic manner, superresolution microscopy has enabled the imaging of biological structures at resolutions well beyond the diffraction limit. Superresolution optical fluctuation imaging (SOFI) provides an elegant way of overcoming the diffraction limit in all three spatial dimensions by computing higher-order cumulants of image sequences of blinking fluorophores acquired with a conventional widefield microscope. So far, three-dimensional (3D) SOFI has only been demonstrated by sequential imaging of multiple depth positions. Here we introduce a versatile imaging scheme which allows for the simultaneous acquisition of multiple focal planes. Using 3D cross-cumulants, we show that the depth sampling can be increased. Consequently, the simultaneous acquisition of multiple focal planes reduces the acquisition time and hence the photo-bleaching of fluorescent markers. We demonstrate multiplane 3D SOFI by imaging the mitochondria network in fixed C2C12 cells over a total volume of $65\times65\times3.5 \mu\textrm{m}^3$ without depth scanning.Comment: 7 pages, 3 figure