81,315 research outputs found
Increasing Public Perceptions of Stroke
Analysis of publicly available data for the selected county of Rutland Vermont was performed to understand the underlying health problems affecting the county. Although VT overall has better health status indicators, including better access to care, and lower rates of chronic diseases than the nation, pockets of the state have higher rates of chronic diseases including obesity, DM, and cerebrovascular accidents.
Increasing awareness of stroke risk factors and symptoms is a cost-effective method to reduced stroke burden and provide successful treatment.https://scholarworks.uvm.edu/fmclerk/1621/thumbnail.jp
Immigration and the pension system in Spain
In this paper we use a large overlapping generations model with individuals that differ across age, productivity and native status to assess the effects on the pension system of different immigration quotas in the context of an aging population by computing how much should social security taxes be rised in order to pay for the pension burden in two model economies. The first one is the standard model pioneered by Auerbach and Kotlikoff (1987) where skilled and unskilled workers are perfect substitutes in the production process. In the second model economy, individuals with different skill levels are imperfect substitutes as in Canova and Ravn (1998). The main result of the paper is that half of the reduction of the social security tax rate associated with immigration in the standard model is lost when skilled and unskilled individual are imperfect substitutes. Consequently, the standard model with perfect substitution overestimates the ability of immigration inflows to sustain the pension system in Spain
Non-symmetric gravity waves on water of infinite depth
Two different numerical methods are used to demonstrate the existence of and calculate non-symmetric gravity waves on deep water. It is found that they appear via spontaneous symmetry-breaking bifurcations from symmetric waves. The structure of the bifurcation tree is the same as the one found by Zufiria (1987) for waves on water of finite depth using a weakly nonlinear Hamiltonian model. One of the methods is based on the quadratic relations between the Stokes coefficients discovered by Longuet-Higgins (1978a). The other method is a new one based on the Hamiltonian structure of the water-wave problem
Symmetry breaking in periodic and solitary gravity-capillary waves on water of finite depth
A weakly nonlinear model is developed from the Hamiltonian formulation of water waves, to study the bifurcation structure of gravity-capillary waves on water of finite depth. It is found that, besides a very rich structure of symmetric solutions, non-symmetric Wilton's ripples exist. They appear via a spontaneous symmetry breaking bifurcation from symmetric solutions. The bifurcation tree is similar to that for gravity waves. The solitary wave with surface tension is studied with the same model close to a critical depth. It is found that the solution is not unique, and that further non-symmetric solitary waves are possible. The bifurcation tree has the same structure as for the case of periodic waves. The possibility of checking these results in low-gravity experiments is postulated
Decreasing Inequality Under Latin America's "Social Democratic" and " Populist" Govenments: Is the Difference Real?
This paper addresses the claim that the governments of Argentina, Bolivia, Ecuador and Venezuela, Latin America's so-called "left-populist" governments, have failed to effectively reduce inequality in the 2000s and have only benefitted from high commodity prices and other benign external conditions. In particular, it examines the econometric evidence presented by McLeod and Lustig (2011) that the "social democratic" governments of Brazil, Chile and Uruguay were more successful and finds that their original results are highly sensitive to the use of data from the Socioeconomic Database for Latin America and the Caribbean (SEDLAC). Conducting the same analysis using data on income inequality from the Economic Commission for Latin America and the Caribbean (ECLAC) leads to the exact opposite result: it is the so-called "left-populist" governments who appear to have effectively reduced income inequality over the last decade. The key difference between data from SEDLAC and ECLAC is that the latter corrects for income underreporting -- when households in an income survey underreport their true amount of income, thus biasing the measurement of inequality -- while the former does not. Absent reasonable criteria for choosing one dataset over the other, the paper suggests that any econometric results based on income inequality data should prove robust to both sources
Oscillatory spatially periodic weakly nonlinear gravity waves on deep water
A weakly nonlinear Hamiltonian model is derived from the exact water wave equations to study the time evolution of spatially periodic wavetrains. The model assumes that the spatial spectrum of the wavetrain is formed by only three free waves, i.e. a carrier and two side bands. The model has the same symmetries and invariances as the exact equations. As a result, it is found that not only the permanent form travelling waves and their stability are important in describing the time evolution of the waves, but also a new kind of family of solutions which has two basic frequencies plays a crucial role in the dynamics of the waves. It is also shown that three is the minimum number of free waves which is necessary to have chaotic behaviour of water waves
Polyhomogeneous expansions close to null and spatial infinity
A study of the linearised gravitational field (spin 2 zero-rest-mass field)
on a Minkowski background close to spatial infinity is done. To this purpose, a
certain representation of spatial infinity in which it is depicted as a
cylinder is used. A first analysis shows that the solutions generically develop
a particular type of logarithmic divergence at the sets where spatial infinity
touches null infinity. A regularity condition on the initial data can be
deduced from the analysis of some transport equations on the cylinder at
spatial infinity. It is given in terms of the linearised version of the Cotton
tensor and symmetrised higher order derivatives, and it ensures that the
solutions of the transport equations extend analytically to the sets where
spatial infinity touches null infinity. It is later shown that this regularity
condition together with the requirement of some particular degree of tangential
smoothness ensures logarithm-free expansions of the time development of the
linearised gravitational field close to spatial and null infinities.Comment: 24 pages, 5 figures. To appear in: The Conformal Structure of
Spacetimes. Geometry, Analysis, Numerics. J. Frauendiner and H. Friedrich
eds. Springe
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