Age and growth parameters of cachara Pseudoplastystoma reticulatum (Siluriformes, Pimelodidae) from the Cuiabá River, Brazil

Age and growth parameters of cachara Pseudoplatystoma reticulatum (Eigenmann & Eigenmann, 1889) (Siluriformes, Pimelodidae) (males and females) were estimated through the analysis of growth rings in spines of pectoral fins. Fish were collected from January to December 2007, in the area directly influenced by the Aproveitamento Múltiplo de Manso (APM Manso) and in the Cuiabá River (upper parts of the Pantanal). The maximum number of growth rings was seven for males, and eight, for females. The analysis of temporal variations in mean marginal increment showed that rings found in the spines were formed annually, in December. Growth rings were associated to spawning (in the study region from November to March) of the species. The growth curve in length was obtained by the von Bertalanffy model adjusted by the Ford-Walford transformation. The equations are: Ls = 72.7*[1-e-0.44(t+1.5974)] for males, and Ls = 84.5*[1-e-0.33(t+2.0943)] for females. The equations that describe the growth curve in weight are: Wt = 4991.61*[1-e-0.44 (t+1.5974] 2.70 for males and Wt = 7503.17*[1-e-0.33 (t+2.0943] 2.99 for females.

A territorial approach to firm entry: The effect of city size

This paper concerns the effects of territorial factors on the processes involved in the creation of manufacturing firms in Spanish cities. Most contributions have focused on regional factors rather than urban ones. Here we assume that it is possible to identify certain urban factors that attract new firms. We use data for the entry of firms in Spanish manufacturing industries between 1994 and 2002. This paper contributes to the existing literature on market entry. Key words: cities, regions, firm entry and Spanish economy. JEL: R0, R12, L60

User-friendly parallel computations with econometric examples

This paper shows how a high level matrix programming language may be used to perform Monte Carlo simulation, bootstrapping, estimation by maximum likelihood and GMM, and kernel regression in parallel on symmetric multiprocessor computers or clusters of workstations. The implementation of parallelization is done in a way such that an investigator may use the programs without any knowledge of parallel programming. A bootable CD that allows rapid creation of a cluster for parallel computing is introduced. Examples show that parallelization can lead to important reductions in computational time. Detailed discussion of how the Monte Carlo problem was parallelized is included as an example for learning to write parallel programs for Octave.

Urban spatial structure and suburbanisation. The case of the Barcelona Metropolitan

The metropolitan spatial structure displays various patterns, sometimes monocentricity and sometimes multicentricity, which seems much more complicated than the exponential density function used in classic works such as Clark (1961), Muth (1969) or Mills (1973) among others, can effectively represent. It seems that a more flexible density function,such as cubic spline function (Anderson (1982), Zheng (1991), etc.) to describe the density-accessibility relationship is needed. Also, accessibility, the fundamental determinant of density variations, is only partly captured by the inclusion of distance to the city centre as an explanatory variable. Steen (1986) has proposed to correct that miss-especification by including an additional gradient for distance to the nearest transportation axis. In identifying the determinants of urban spatial structure in the context of inter-urban systems, some of the variables proposed by Muth (1969), Mills (1973) and Alperovich (1983) such as city age or population, make no sense in the case of a single urban system. All three criticism to the exponential density function and its determinants apply for the Barcelona Metropolitan Region, a polycentric conurbation structured on well defined transportation axes.

The black-white test score gap widens with age?

We re-examine the theoretical concept of a production function for cognitive achievement, and argue that an indirect production function that depends upon the variables that constrain parents' choices is both moretractable from an econometric point of view, and more interesting from an economic point of view than is a direct production function that depends upon a detailed list of direct inputs such as number of books in the household. We estimate flexible econometric models of indirect production functions for two achievement measures from the Woodcock-Johnson Revised battery, using data from two waves of the Child Development Supplement to the PSID. Elasticities of achievement measures with respect to family income and parents' educational levels are positive and significant. Gaps between scores of black and white children narrow or remain constant as children grow older, a result that differs from previous findings in the literature. The elasticities of achievement scores with respect to family income are substantially higher for children of black families, and there are some notable difference in elasticities with respect to parents' educational levels across blacks and whites.

Poliomyelitis: epidemiological aspects in Rio de Janeiro (Guanabara State) and adjacent areas in the period from 1961 to 1970

Based on the available data from the Hospital responsible for the care of paralitic poliomyelitis cases in Rio de Janeiro City (Guanabara State) and adjacent areas, and the laboratory studies carried out on these patients, the authors analize epidemiological aspects of poliomyelitis in a period of ten years (1961 to 1970). Paralitic poliomyelitis remains a public health problem, with a typical incidence in the less than 4 year age group. All three poliovirus types have been prevalent for at least one period of time during the last ten years. Trivalent oral vaccine has been used since 1961 but the vaccination levels achieved were not enough to a permanent control of the disease. A definite seasonal distribution of cases could not be observed with the available data. Active mass campaign vaccinations with previous motivation of all segments of the population, specially the low-income groups instead of passive waiting of children in Vaccination Centers seems to be the best aproach to control poliomyelitis in this area.

Regulation in the Age of Globalization: The Difussion of Regulatory Agencies across Europe and Latin America

One of the most notable characteristics of the change in governance of the past two decades has been the restructuring of the state, most notably the delegation of authority from politicians and ministries to technocrats and regulatory agencies. Our unique dataset on the extent of these reforms in seven sectors in 36 countries reveals the widespread diffusion of these reforms in recent decades. In 1986 there were only 23 agencies across these sectors and countries (less than one agency per country); by 2002 this number had increased more than seven-fold, to 169. On average these 36 countries each have more than four agencies in the seven sectors studied. Yet the widespread diffusion of these reforms is characterized by cross-regional and cross-sectoral variations. Our data reveal two major variations: first, reforms are more widespread in economic regulation that in social spheres; second, regulatory agencies in the social spheres are more widespread in Europe than in Latin America. Why these variations in the spread of the reforms? In this paper we present for the first time the regulatory gaps across regions and sectors and then move on to offer some explanations for these gaps in a way that sheds some light on the nature of these reforms and on their limits. Our explanatory framework combines diffusion and structural explanations and in doing so sheds new light on the global diffusion of public policy ideas.

The Paralympic Village: a barrier-free city

Article describing the design standards and their use for Paralympic facilities. This article was published in the book entitled Olympic Villages: a hundred years of urban planning and shared experiences compiling the papers given at the 1997 International Symposium on International Chair in Olympism (IOC-UAB).

Retinal pigment epithelium tears after intravitreal injection of ranibizumab for predominantly classic neovascular membranes secondary to age-related macular degeneration.

PURPOSE: Retinal pigment epithelium (RPE) tear is an extremely rare complication in patients with classic neovascular membranes without RPE detachment. We evaluate their incidence and functional outcome following treatment with intravitreal ranibizumab. METHODS: Observational study of 72 consecutive patients (74 eyes) treated at Jules Gonin University Eye Hospital, Lausanne, with intravitreal ranibizumab 0.5 mg for classic choroidal neovascularization (CNV) between March 2006 and February 2008. Best-corrected visual acuity (BCVA), fundus examination and optical coherence tomography were recorded monthly; fluorescein angiography was performed at baseline and repeated at least every 3 months. RESULTS: RPE tears occurred in four (5.4%) eyes temporal to the fovea, after a mean of four injections (range 3-6). Mean baseline BCVA was 0.25 decimal equivalent (logMAR 0.67) and improved despite the RPE tear to 0.6 decimal equivalent (logMAR 0.22). CONCLUSION: RPE tears following intravitreal ranibizumab injections for classic CNV can occur in about 5% of patients, even in the absence of baseline RPE detachment. Nevertheless, vision may improve provided the fovea is not involved.

New York City: "gilt cage" or "promised land" ? : representations of urban space in Edith Wharton and Anzia Yezierska

This thesis explores the importance of literary New York City in the urban narratives of Edith Wharton and Anzia Yezierska. It specifically looks at the Empire City of the Progressive Period when the concept of the city was not only a new theme but also very much a typical American one which was as central to the American experience as had been the Western frontier. It could be argued, in fact, that the American city had become the new frontier where modern experiences like urbanization, industrialization, immigration, and also women's emancipation and suffrage, caused all kinds of sensations on the human scale from smoothly lived assimilation and acculturation to deeply felt alienation because of the constantly shifting urban landscape. The developing urban space made possible the emergence of new female literary protagonists like the working girl, the reformer, the prostitute, and the upper class lady dedicating her life to 'conspicuous consumption'. Industrialization opened up city space to female exploration: on the one hand, upper and middle class ladies ventured out of the home because of the many novel urban possibilities, and on the other, lower class and immigrant girls also left their domestic sphere to look for paid jobs outside the home. New York City at the time was not only considered the epicenter of the world at large, it was also a city of great extremes. Everything was constantly in flux: small brownstones made way for ever taller skyscrapers and huge waves of immigrants from Europe pushed native New Yorkers further uptown on the island, adding to the crowdedness and intensity of the urban experience. The city became a polarized urban space with Fifth Avenue representing one end of the spectrum and the Lower East Side the other. Questions of space and the urban home greatly mattered. It has been pointed out that the city setting functions as an ideal means for the display of human nature as well as social processes. Narrative representations of urban space, therefore, provide a similar canvas for a protagonist's journey and development. From widely diverging vantage points both Edith Wharton and Anzia Yezierska thus create a polarized city where domesticity is a primal concern. Looking at all of their New York narratives by close readings of exterior and interior city representations, this thesis shows how urban space greatly affects questions of identity, assimilation, and alienation in literary protagonists who cannot escape the influence of their respective urban settings. Edith Wharton's upper class "millionaire" heroines are framed and contained by the city interiors of "old" New York, making it impossible for them to truly participate in the urban landscape in order to develop outside of their 'Gilt Cages'. On the other side are Anzia Yezierska's struggling "immigrant" protagonists who, against all odds, never give up in their urban context of streets, rooftops, and stoops. Their New York City, while always challenging and perpetually changing, at least allows them perspectives of hope for a 'Promised Land' in the making. Central for both urban narrative approaches is the quest for a home as an architectural structure, a spiritual resting place, and a locus for identity forming. But just as the actual city embraces change, urban protagonists must embrace change also if they desire to find fulfillment and success. That this turns out to be much easier for Anzia Yezierska's driven immigrants rather than for Edith Wharton's well established native New Yorkers is a surprising conclusion to this urban theme.

Age-related change in melanin-based coloration of Barn owls (Tyto alba): females that become more female-like and males that become more male-like perform better

Ornament expression fluctuates with age in many organisms. Whether these changes are adaptively plastic is poorly known. In order to understand the ultimate function of melanin-based ornaments, we studied their within-individual fluctuations and their covariation with fitness-related traits. In barn owls (Tyto alba), individuals vary from reddish-brown pheomelanic to white and from immaculate to marked with black eumelanic spots, males being less reddish and less spotted than females. During the first molt, both sexes became less pheomelanic, females displayed larger spots and males fewer spots, but the extent of these changes was not associated with reproduction. At subsequent molts, intra-individual changes in melanin-based traits covaried with simultaneous reproduction changes. Adult females bred earlier in the season and laid larger eggs when they became scattered with larger spots, while adults of both sexes produced larger broods when they became whiter. These results suggest that the production of melanin pigments and fitness-related life history traits are concomitantly regulated in a sex-specific way.

Percepción de riesgo, estrés y consumo de drogas. Estudio transcultural entre adolescentes de Barcelona y Bogotá

Este estudio explora las diferencias en los hábitos de consumo de sustancias psicoactivas, entre jóvenes de Barcelona y Bogotá. Evalúa la influencia de la percepción de riesgo sobre hábitos de consumo y estrategias de afrontamiento. Adicionalmente examina la influencia de la gravedad percibida de una situación estresante sobre estas últimas. Participaron 865 jóvenes de ambas ciudades, entre los 15 y los 18 años. Se utilizaron las variables de riesgo estudiadas por Benthin, Slovic y Severson (1993) para evaluar la percepción de riesgo. Los hábitos de consumo se evaluaron mediante la frecuencia, la intención de consumo, así como la edad de inicio. Se utilizó el CRI:Youth de Moos (1992) para determinar las estrategias de afrontamiento y la valoración del problema estresante. Se encontró que existen diferencias en la edad en que se inicia el consumo de alcohol y en la que se embriagan por primera vez según el género, la ciudad donde residen y la edad del adolescente. Los jóvenes de Barcelona tienen una propensión y un consumo real de marihuana y tabaco mayor que los jóvenes de Bogotá. Percibir placer o beneficios predice un incremento en la intención y la frecuencia de consumo de la mayoría de las sustancias. La facilidad para acceder a éstas sólo presenta una asociación con el uso frecuente del tabaco. Los datos sugieren que la gravedad percibida de estresores relativos a las drogas y la ciudad de residencia tienen un efecto sobre la utilización de las estrategias de evitación y aproximación cognitiva. Adicionalmente no se detectaron diferencias en función de las estrategias de afrontamiento empleadas según las variables de percepción de riesgo a excepción de la presión percibida, la cual aumenta el uso de la reevaluación del problema y la búsqueda de recompensas.