3,332 research outputs found
Recent Trends in the Distribution of Income: Labor, Wealth and More Complete Measures of Well Being
>The impact of the great recession on inequality is unclear. Because the crises in the housing and stock markets and mass job loss affect incomes from across the entire distribution, the overall impact on inequality is difficult to determine. Early speculation using a variety of narrow measures of earnings, income and consumption yield contradictory results. In this paper, we develop new estimates of income inequality based on ‘more complete income’ (MCI), which augments standard income measures with those that are accrued from the ownership of wealth. We use the 1989-2007 Surveys of Consumer Finances, and also construct MCI measures for 2009 based on projections of assets, income, and earnings. We investigate the level and trend in MCI inequality and compare it to other estimates of overall and ‘high incomes’ in the literature. Compared to standard measures of income, MCI suggests higher levels of inequality and slightly larger increases in inequality over time. Several MCI-based inequality measures peaked in 2007 at their highest levels in twenty years. The combined impact of the “great recession” on the housing, stock, and labor markets after 2007 has reduced some measures of income inequality at the top of the MCI distribution. Despite declining from the 2007 peak, however, inequality remains as high as levels experienced earlier in the decade, and much higher than most points over the last twenty years. In the middle of the income distribution, the declines in income from wealth after 2007 were the result of diminished value of residential real estate; at the top of the distribution declines in the value of business assets had the greatest impact. We also assess the level and trend in the functional distribution of income between capital and labor, and find a rising share of income accruing to real capital or wealth from 1989 to 2007. The recent economic crisis has diminished the capital share back to levels from 2004. Contrary to the findings of other researchers, we find that the labor share of income among high-income groups declined between 1992 and 2007.
Resistance to Fracture of Two All-Ceramic Crown Materials Following Endodontic Access
Statement of problem
There is currently no protocol for managing endodontic access openings for all-ceramic crowns. A direct restorative material is generally used to repair the access opening, rendering a repaired crown as the definitive restoration. This endodontic procedure, however, may weaken the restoration or initiate microcracks that may propagate, resulting in premature failure of the restoration. Purpose
The purpose of this in vitro study was to evaluate how an endodontic access opening prepared through an all-ceramic crown altered the structural integrity of the ceramic, and the effect of a repair of this access on the load to failure of an all-ceramic crown. Material and methods
Twenty-four alumina (Procera) and 24 zirconia (Procera) crowns were fabricated and cemented (Rely X Luting Plus Cement) onto duplicate epoxy resin dies. Twelve crowns of each were accessed to simulate root canal treatment therapy. Surface defects of all accessed specimens were evaluated with an environmental scanning electron microscope. The specimens were repaired with a porcelain repair system (standard adhesive resin/composite resin protocol) and were loaded to failure in a universal testing machine. Observations made visually and microscopically noted veneer delamination from the core, core fracture, shear within the veneer porcelain, or a combination thereof. A Kruskal-Wallis test was used to determine if a significant difference (α=.05) in load to failure existed between the 4 groups, and a Mann-Whitney test with a Bonferroni correction (P Results
All specimens exhibited edge chipping around the access openings. Some displayed larger chips within the veneering porcelain, and 4 zirconia crowns showed radial crack formation. There was a significant difference in load to failure among all groups with the exception of the alumina intact and repaired specimens (P=.695). The alumina crowns generally showed fracture of the coping with the veneering porcelain still bonded to the core, whereas the zirconia copings tended not to fracture but experienced veneering porcelain delamination. Conclusion
Endodontic access through all-ceramic crowns resulted in a significant loss of strength in the zirconia specimens but not in the alumina specimens
A vortex population viability analysis model for the Chacoan peccary (catagonus wagneri)
El quimilero o taguá (Catagonus wagneri) es una especie amenazada, endémica del Chaco Seco, para la cual disponemos de poca información. Para estimar cuantitativamente el riesgo de disminución y extinción de sus poblaciones silvestres generamos modelos de viabilidad poblacional. Con estos modelos matemáticos se pueden identificar factores naturales y antrópicos complejos que interactúan y que influyen en la persistencia y la salud de una población. Los modelos también se pueden utilizar para evaluar los efectos de diferentes estrategias de gestión, permitiendo identificar las acciones de conservación más efectivas para una población o especie. Además, estos modelos se pueden usar para identificar las necesidades de investigación debido a que ponen en evidencia los vacíos de información sobre la especie. Utilizando estos modelos, evaluamos la proyección poblacional en las condiciones actuales y en comparación con posibles variaciones existentes en el sistema. Para generar los parámetros ingresados en los modelos realizamos una reunión de especialistas y una revisión bibliográfica. Trabajó con valores de línea de base (base), mínimos (mín.) y máximos (máx.). Generamos diferentes modelos ante diferentes escenarios y testeamos la sensibilidad a la incertidumbre de cada modelo. Esto permitió establecer prioridades de investigación. Además, determinamos los tamaños mínimos de población viable considerando la incertidumbre y analizamos los posibles efectos de la caza en una población de esta especie.Fil: Leus, Kritin. International Union for Conservation of Nature. Species Survival Commission; DinamarcaFil: Altrichter, Mariana. International Union for Conservation of Nature. Species Survival Commission; Estados UnidosFil: Desbiez, Arnaud. International Union for Conservation of Nature. Species Survival Commission; BrasilFil: Camino, Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Giordano, Anthony J.. S.P.E.C.I.E.S.; Estados UnidosFil: Campos Krauer, Juan Manuel. University of Florida. Department of Wildlife Ecology and Conservation; Estados Unidos. Centro Chaqueño para la Conservación y la Investigación; ParaguayFil: Brooks, Daniel M.. Houston Museum Of Natural Science; Estados UnidosFil: Thompson, Jeffrey. Consejo Nacional de Ciencia y Tecnología; ParaguayFil: Núñez Regueiro, Mauricio Manuel. University of Florida. Department of Wildlife Ecology and Conservation; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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