24,526 research outputs found

    Human Development of Peoples

    Get PDF
    This paper provides a framework and estimates of Enrollment Rates per natural and combines them with previous Income and Child Mortality per natural estimates by Clemens and Pritchett (2008) to produce a Human Development Index Per Natural. The methodology is applied for 1990 and 2000 to provide estimates of growth rates of this measure over the period. The paper also develops and illustrates a framework for estimating an education place premium, and discusses how it is related to per natural measures. The peoples of the least developed countries stand to gain the most from international migration, but there are potentially significant gains to migration between developing countries as well.Migration, Human Development, Education

    Human Development of Peoples

    Get PDF
    This paper provides a framework and estimates of Enrollment Rates per natural and combines them with previous Income and Child Mortality per natural estimates by Clemens and Pritchett (2008) to produce a Human Development Index Per Natural. The methodology is applied for 1990 and 2000 to provide estimates of growth rates of this measure over the period. The paper also develops and illustrates a framework for estimating an education place premium, and discusses how it is related to per natural measures. The peoples of the least developed countries stand to gain the most from international migration, but there are potentially significant gains to migration between developing countries as well.Migration, Human Development, Education

    Unveiling the circumstellar environment towards a massive young stellar object

    Get PDF
    As a continuation of a previous work, in which we found strong evidence of massive molecular outflows towards a massive star forming site, we present a new study of this region based on very high angular resolution observations with the aim of discovering the outflow driven mechanism. Using near-IR data acquired with Gemini-NIRI at the broad H- and Ks-bands, we study a region of 22" x 22" around the UCHII region G045.47+0.05, a massive star forming site at the distance of about 8 kpc. To image the source with the highest spatial resolution possible we employed the adaptative optic system ALTAIR, achieving an angular resolution of about 0.15". We discovered a cone-like shape nebula with an opening angle of about 90 degree extending eastwards the IR source 2MASS J19142564+1109283, a very likely MYSO. This morphology suggests a cavity that was cleared in the circumstellar material and its emission may arise from scattered continuum light, warm dust, and likely emission lines from shock-excited gas. The nebula, presenting arc-like features, is connected with the IR source through a jet-like structure, which is aligned with the blue shifted CO outflow found in a previous study. The near-IR structure lies ~3" north of the radio continuum emission, revealing that it is not spatially coincident with the UCHII region. The observed morphology and structure of the near-IR nebula strongly suggest the presence of a precessing jet. In this study we have resolved the circumstellar ambient (in scale of a thousand A.U.) of a distant MYSO, indeed one of the farthest cases.Comment: Accepted in A&A Letters (October 2013

    The performance of decentralized school systems : evidence from Fe y Alegría in Venezuela

    Get PDF
    This program evaluation estimates the effects on standardized test scores of graduating from the Fe y Alegría private school system in Venezuela. The authors find an Average Treatment Effect on the order of 0.1 standard deviations (approximately 16 percent of the average score), using a control group of public school students. These effects are significantly larger for households at the bottom of the distribution, and smaller for those at the top. The authors posit that the better performance of the Fe y Alegría system stems from their labor contract flexibility and decentralized administrative structure.Tertiary Education,Education For All,Secondary Education,Primary Education,Teaching and Learning

    Discriminating dynamical from additive noise in the Van der Pol oscillator

    Full text link
    We address the distinction between dynamical and additive noise in time series analysis by making a joint evaluation of both the statistical continuity of the series and the statistical differentiability of the reconstructed measure. Low levels of the latter and high levels of the former indicate the presence of dynamical noise only, while low values of the two are observed as soon as additive noise contaminates the signal. The method is presented through the example of the Van der Pol oscillator, but is expected to be of general validity for continuous-time systems.Comment: 12 pages (Elsevier LaTeX class), 4 EPS figures, submitted to Physica D (4 july 2001

    Mapping the 13CO/C18O abundance ratio in the massive star forming region G29.96-0.02

    Full text link
    Estimating molecular abundances ratios from the direct measurement of the emission of the molecules towards a variety of interstellar environments is indeed very useful to advance in our understanding of the chemical evolution of the Galaxy, and hence of the physical processes related to the chemistry. It is necessary to increase the sample of molecular clouds, located at different distances, in which the behavior of molecular abundance ratios, such as the 13CO/C18O ratio (X), is studied in detail. We selected the well-studied high-mass star-forming region G29.96-0.02, located at a distance of about 6.2 kpc, which is an ideal laboratory to perform this kind of studies. To study the X towards this region it was used 12CO J=3-2 data obtained from COHRS, 13CO and C18O J=3-2 data from CHIMPS, and 13CO and C18O J=2-1 data retrieved from the CDS database (observed with the IRAM 30m telescope). The distribution of column densities and X throughout the molecular cloud was studied based on LTE and non-LTE methods. Values of X between 1.5 to 10.5, with an average of 5, were found, showing that, besides the dependency between X and the galactocentric distance, the local physical conditions may strongly affect this abundance ratio. We found that correlating the X map with the location of the ionized gas and dark clouds allows us to suggest in which regions the far-UV radiation stalls in dense gaseous components, and in which ones it escapes and selectively photodissociates the C18O isotope. The non-LTE analysis shows that the molecular gas has very different physical conditions, not only spatially across the cloud, but also along the line of sight. This kind of studies may represent a tool to indirectly estimate (from molecular lines observations) the degree of photodissociation in molecular clouds, which is indeed useful to study the chemistry in the interstellar medium.Comment: Accepted in A&A (July 10, 2018

    Regularity of solutions to a fractional elliptic problem with mixed Dirichlet-Neumann boundary data

    Get PDF
    In this work we study regularity properties of solutions to fractional elliptic problems with mixed Dirichlet-Neumann boundary data when dealing with the Spectral Fractional Laplacian
    corecore