Correlations between trabecular bone score, measured using anteroposterior dual-energy x-ray absorptiometry acquisition, and 3-dimensional parameters of bone microarchitecture: an experimental study on human cadaver vertebrae.

Developing a novel technique for the efficient, noninvasive clinical evaluation of bone microarchitecture remains both crucial and challenging. The trabecular bone score (TBS) is a new gray-level texture measurement that is applicable to dual-energy X-ray absorptiometry (DXA) images. Significant correlations between TBS and standard 3-dimensional (3D) parameters of bone microarchitecture have been obtained using a numerical simulation approach. The main objective of this study was to empirically evaluate such correlations in anteroposterior spine DXA images. Thirty dried human cadaver vertebrae were evaluated. Micro-computed tomography acquisitions of the bone pieces were obtained at an isotropic resolution of 93μm. Standard parameters of bone microarchitecture were evaluated in a defined region within the vertebral body, excluding cortical bone. The bone pieces were measured on a Prodigy DXA system (GE Medical-Lunar, Madison, WI), using a custom-made positioning device and experimental setup. Significant correlations were detected between TBS and 3D parameters of bone microarchitecture, mostly independent of any correlation between TBS and bone mineral density (BMD). The greatest correlation was between TBS and connectivity density, with TBS explaining roughly 67.2% of the variance. Based on multivariate linear regression modeling, we have established a model to allow for the interpretation of the relationship between TBS and 3D bone microarchitecture parameters. This model indicates that TBS adds greater value and power of differentiation between samples with similar BMDs but different bone microarchitectures. It has been shown that it is possible to estimate bone microarchitecture status derived from DXA imaging using TBS.

One Unshakable Vision: World Class Schools for Iowa, October 3, 2011

Iowans have long shared a deep commitment to giving our children the best education possible. We recognize young people today must meet higher expectations than ever to thrive in this global, knowledge-based economy. For the sake of our children and our state, it is vitally important that we build on our tradition of excellence to improve our schools. Iowa’s house of education still has a strong foundation, but it is also in need of a major remodel to be ready for the days ahead.

Analysis and spatial modeling of the indoor radon Swiss data

The present research deals with an important public health threat, which is the pollution created by radon gas accumulation inside dwellings. The spatial modeling of indoor radon in Switzerland is particularly complex and challenging because of many influencing factors that should be taken into account. Indoor radon data analysis must be addressed from both a statistical and a spatial point of view. As a multivariate process, it was important at first to define the influence of each factor. In particular, it was important to define the influence of geology as being closely associated to indoor radon. This association was indeed observed for the Swiss data but not probed to be the sole determinant for the spatial modeling. The statistical analysis of data, both at univariate and multivariate level, was followed by an exploratory spatial analysis. Many tools proposed in the literature were tested and adapted, including fractality, declustering and moving windows methods. The use of Quan-tité Morisita Index (QMI) as a procedure to evaluate data clustering in function of the radon level was proposed. The existing methods of declustering were revised and applied in an attempt to approach the global histogram parameters. The exploratory phase comes along with the definition of multiple scales of interest for indoor radon mapping in Switzerland. The analysis was done with a top-to-down resolution approach, from regional to local lev¬els in order to find the appropriate scales for modeling. In this sense, data partition was optimized in order to cope with stationary conditions of geostatistical models. Common methods of spatial modeling such as Κ Nearest Neighbors (KNN), variography and General Regression Neural Networks (GRNN) were proposed as exploratory tools. In the following section, different spatial interpolation methods were applied for a par-ticular dataset. A bottom to top method complexity approach was adopted and the results were analyzed together in order to find common definitions of continuity and neighborhood parameters. Additionally, a data filter based on cross-validation was tested with the purpose of reducing noise at local scale (the CVMF). At the end of the chapter, a series of test for data consistency and methods robustness were performed. This lead to conclude about the importance of data splitting and the limitation of generalization methods for reproducing statistical distributions. The last section was dedicated to modeling methods with probabilistic interpretations. Data transformation and simulations thus allowed the use of multigaussian models and helped take the indoor radon pollution data uncertainty into consideration. The catego-rization transform was presented as a solution for extreme values modeling through clas-sification. Simulation scenarios were proposed, including an alternative proposal for the reproduction of the global histogram based on the sampling domain. The sequential Gaussian simulation (SGS) was presented as the method giving the most complete information, while classification performed in a more robust way. An error measure was defined in relation to the decision function for data classification hardening. Within the classification methods, probabilistic neural networks (PNN) show to be better adapted for modeling of high threshold categorization and for automation. Support vector machines (SVM) on the contrary performed well under balanced category conditions. In general, it was concluded that a particular prediction or estimation method is not better under all conditions of scale and neighborhood definitions. Simulations should be the basis, while other methods can provide complementary information to accomplish an efficient indoor radon decision making.

Association between substance use and psychosocial characteristics among adolescents of the Seychelles.

BACKGROUND: We examined the associations between substance use (cigarette smoking, alcohol drinking, and cannabis use) and psychosocial characteristics at the individual and family levels among adolescents of the Seychelles, a rapidly developing small island state in the African region. METHODS: A school survey was conducted in a representative sample of 1432 students aged 11-17 years from all secondary schools. Data came from a self-administered anonymous questionnaire conducted along a standard methodology (Global School-based Health Survey, GSHS). Risk behaviors and psychosocial characteristics were dichotomized. Association analyses were adjusted for a possible classroom effect. RESULTS: The prevalence of cigarette smoking, alcohol drinking and cannabis use was higher in boys than in girls and increased with age. Age-adjusted and multivariate analyses showed that several individual level characteristics (e.g. suicidal ideation and truancy) and family level characteristics (e.g. poor parental monitoring) were associated with substance use among students. CONCLUSIONS: Our results suggest that health promotion programs should simultaneously address multiple risk behaviors and take into account a wide range of psychosocial characteristics of the students at the individual and family levels.

Unconventional Determinants of Greenhouse Gas Emissions: The Role of Trust

[cat] Les normes socials han estat incloses en la teoria de l’acció col.lectiva per a superar les dificultats per explicar perquè la gestió del béns comuns podria ser més efectiva quan s’autoregula per les mateixes comunitats. El paper rellevant de la confiança en els altres s’ha identificat en diversos contextos d’acció social a nivell local, però només recentment s’ha considerat la idea que també podria ser rellevant en el cas de béns comuns de caire global, seguint l’evidència bàsicament descriptiva recollida per Elinor Ostrom. Però fins ara no hi havia proves quantitatives disponibles d’aquesta idea. Utilitzant un conjunt de dades de 29 països europeus durant el període 1990-2007, donem evidència empírica a favor del paper del nivell de confiança en els altres en el context dels béns públics globals. Concloem que el nivell de confiança en els altres té un impacte reductor de les emissions de gasos d’efecte hivernacle; per exemple, l’extrapolació dels resultats implicaria una reducció d’emissions d’Espanya del 12,5% si el nivell mitjà de confiança en els altres dels espanyols fos tan elevat com els dels suecs.

Unconventional Determinants of Greenhouse Gas Emissions: The Role of Trust

[cat] Les normes socials han estat incloses en la teoria de l’acció col.lectiva per a superar les dificultats per explicar perquè la gestió del béns comuns podria ser més efectiva quan s’autoregula per les mateixes comunitats. El paper rellevant de la confiança en els altres s’ha identificat en diversos contextos d’acció social a nivell local, però només recentment s’ha considerat la idea que també podria ser rellevant en el cas de béns comuns de caire global, seguint l’evidència bàsicament descriptiva recollida per Elinor Ostrom. Però fins ara no hi havia proves quantitatives disponibles d’aquesta idea. Utilitzant un conjunt de dades de 29 països europeus durant el període 1990-2007, donem evidència empírica a favor del paper del nivell de confiança en els altres en el context dels béns públics globals. Concloem que el nivell de confiança en els altres té un impacte reductor de les emissions de gasos d’efecte hivernacle; per exemple, l’extrapolació dels resultats implicaria una reducció d’emissions d’Espanya del 12,5% si el nivell mitjà de confiança en els altres dels espanyols fos tan elevat com els dels suecs.

Standardikustannusten ja toteutuneiden kustannusten erotus

Työn tarkoituksena oli selvittää, eroavatko toteutuneet kustannukset standardikustannuksista sähkötarviketeollisuudessa. Kustannusten eroa, varianssia, pyrittiin analysoimaan mahdollisimman tarkasti, jotta varianssien tyyppi ja niiden lähteet selviäisivät. Tavoitteena oli myös selvittää, miten varianssi vaikuttaa standardien laskentaan ja siirtohinnoitteluun. Tutkimus tehtiin tapaustutkimuksena eräästä sähkötarviketeollisuuden yrityksestä. Toteutuneet kustannukset saatiin suoraan kirjanpidosta ja niitä verrattiin standardikustannuksiin. Standardikustannukset jaettiin eri kustannuskomponentteihin, jotka otettiin kohdeyrityksen toiminnanohjausjärjestelmästä. Kustannuskomponenttitasoista tietoa muokattiin tuloslaskentamuotoiseen muotoon, jotta toteutuneita kustannuksia voitiin verrata kerättyyn tietoon. Varianssianalyysistä selvisi, että toteutuneiden kustannusten ja standardikustannusten välillä on varianssia. Se jakautuu materiaalivarianssiin, työvarianssiin, ja yleiskustannuslisävarianssiin. Varianssien perusteella analysoitiin vaikutuksia standardien ja siirtohintojen laskentaan. Näiden tietojen perusteella työn lopuksi on mietitty parantamistoimenpiteitä varianssien ehkäisemiseksi.

Globalization and Its Impact on Assessment: Moving Toward a New Story

Globalization has resulted in large-scale international and local assessments closely tied to notions of accountability and competitiveness in a globalized economy. Although policy makers seek to ensure citizens meet the demands of a global knowledge-based economy, such assessments may also impede the development of requisite 21st century skills. While standardization currently is viewed as the most effective measurement of student achievement, several Canadian and international jurisdictions are moving toward assessment for learning (AfL). This conceptual study sought to identify whether AfL or standardized assessment most effectively meets 21st century learning goals in the wake of rapid global change. It applies a Story Model theoretical framework to understand the current, the new emerging, and the future ideal story of education from a personal, cultural, and global lens. The study examines the main critiques and/or challenges of standardized testing, the benefits of AfL for student learning, and new teaching and assessment approaches to the development of 21st century learning goals. The study applies the Story Model’s inside-outside/past-future approach to determine the future direction of assessment. Results show that the new story of assessment will most likely entail a model that integrates both standardized testing and in-class assessments in the form of AfL and PBL.

Prevalencia de factores de riesgo cardiovascular en niños de 3 a 17 años

Introducción: Los factores de riesgo de la enfermedad cardiovascular (FRECV) pueden estar presentes desde la infancia y predicen la enfermedad cardiovascular del adulto. Objetivo: Evaluar la prevalencia de FRECV en niños de 3 a 17 años hijos de Enfermeras de la Fundación CardioInfantil - Instituto de cardiología (FCI). Métodos: Estudio de corte transversal analítico. Resultados: 118 niños, edad promedio 7,4 años, desviación estándar 3,86, la mayoría eutróficos 72,0%. Presentaron FRECV como malos hábitos alimenticios 89,0%, sedentarismo 78,8%, exposición a tabaco 19,5%, historia familiar de riesgo cardiovascular 16,1%, sobrepeso 15,3% y obesidad 12,7%. No se encontraron diferencias entre factores de riesgo entre niños y niñas.El sedentarismo en niños con sobrepeso u obesidad fue del 90,9% y en niños eutróficos del 36,5%. Los malos hábitos alimentarios en niños con sobrepeso u obesidad fueron 84,8% y en niños eutróficos 42,4%. Los adolescentes presentaron una mayor exposición a tabaco en comparación con los preescolares y escolares, al igual que una mayor proporción de malos hábitos alimenticios en comparación con ambos grupos. De la totalidad de la población de estudio, el 97,5% presentó al menos un FRECV, y el 42,4% 3 o más FRECV. La presencia de ≥3 FRECV fue mayor en obesos al compararlos con los niños en sobrepeso y eutróficos. Conclusiones: Los resultados del estudio indican que los niños de 3 a 17 años evaluados presentan una alta carga de FRECV, en especial en aquellos con sobrepeso y obesidad.

Construcción de un instrumento para identificar el perfil de emprendedores bogotanos de la última década

El proyecto de investigación que se trabaja centra su atención en la siguiente cuestión: determinar un instrumento de recolección que permita identificar cuáles son las competencias que caracterizan a los emprendedores bogotanos creadores de empresas de rápido crecimiento. La presente es una investigación cualitativa que busca la mejor manera de preparar a los futuros emprendedores desde la educación superior. Si se conocen las competencias que acompañan al emprendedor se puede comprender mejor su capacidad de crear empresa y así buscar una mejor manera de preparar a los futuros emprendedores. Esto es importante para la economía de un país en general, máxime cuando se dan situaciones de depresión económica como el desempleo que se vive en la actualidad. “La creación y el desarrollo de nuevas empresas contribuye decisivamente a lograr el deseado bienestar para la sociedad, dado que permite incrementar el nivel de empleo, impulsar la innovación y mejorar la competitividad” (Acs, Audretch, & Braunerhjelm, 2006, pág. 83). La investigación abarca la búsqueda de competencias a nivel mundial basándose en estudios realizados por diferentes autores (Alles, Durán, Goleman, Shipmann, Varela, Boyatsis, Mc. Clelland y Blancero). El objetivo es desarrollar un instrumento que permita recolectar información de emprendedores bogotanos exitosos, con base en la clasificación de competencias que se realice a lo largo de la investigación.

Lógica en la toma de decisiones de inversión en el sector de extracción de petróleo y gas natural

Este documento se centra en la presentación de información y análisis de la misma a la hora de establecer la manera en que empresas del sector de extracción de gas natural y generación de energía a base de dicho recurso, toman decisiones en cuanto a inversión, centrándose en la lógica que usan a la hora de emprender este proceso. Esto debido a la constante necesidad de establecer procesos que permitan tomar decisiones más acertadas, incluyendo todas las herramientas posibles para tal fin. La lógica es una de estas herramientas, pues permite encadenar factores con el fin de obtener resultados positivos. Por tal razón, se hace importante conocer el uso de esta herramienta, teniendo en cuentas de qué manera y en que contextos es usada. Con el fin de tener una mayor orientación, este estudio estará centrado en un sector específico, el cual es el de la extracción de petróleo y gas natural. Lo anterior entendiendo la necesidad existente de fundamentación teórica que permita establecer de manera clara la forma apropiada de tomar decisiones en un sector tan diverso y complejo como lo es el mencionado. El contexto empresarial actual exige una visión global, no basada en la lógica lineal causal que hoy se tiene como referencia. El sector de extracción de petróleo y gas natural es un ejemplo particular en cuanto a la manera en cuanto se toman decisiones en inversión, puesto que en su mayoría son empresas de capital intensivo, las cuales mantienen un flujo elevado de recursos monetarios.

Perceptual grouping and distance estimates in typical and atypical development: comparing performance across perception, drawing and construction tasks

Perceptual grouping is a pre-attentive process which serves to group local elements into global wholes, based on shared properties. One effect of perceptual grouping is to distort the ability to estimate the distance between two elements. In this study, biases in distance estimates, caused by four types of perceptual grouping, were measured across three tasks, a perception, a drawing and a construction task in both typical development (TD: Experiment 1) and in individuals with Williams syndrome (WS: Experiment 2). In Experiment 1, perceptual grouping distorted distance estimates across all three tasks. Interestingly, the effect of grouping by luminance was in the opposite direction to the effects of the remaining grouping types. We relate this to differences in the ability to inhibit perceptual grouping effects on distance estimates. Additive distorting influences were also observed in the drawing and the construction task, which are explained in terms of the points of reference employed in each task. Experiment 2 demonstrated that the above distortion effects are also observed in WS. Given the known deficit in the ability to use perceptual grouping in WS, this suggests a dissociation between the pre-attentive influence of and the attentive deployment of perceptual grouping in WS. The typical distortion in relation to drawing and construction points towards the presence of some typical location coding strategies in WS. The performance of the WS group differed from the TD participants on two counts. First, the pattern of overall distance estimates (averaged across interior and exterior distances) across the four perceptual grouping types, differed between groups. Second, the distorting influence of perceptual grouping was strongest for grouping by shape similarity in WS, which contrasts to a strength in grouping by proximity observed in the TD participants. (c) 2008 Elsevier Inc. All rights reserved.

Bioclimatic envelope model of climate change impacts on blanket peatland distribution in Great Britain

Blanket peatlands are rain-fed mires that cover the landscape almost regardless of topography. The geographical extent of this type of peatland is highly sensitive to climate. We applied a global process-based bioclimatic envelope model, PeatStash, to predict the distribution of British blanket peatlands. The model captures the present areal extent (Kappa = 0.77) and is highly sensitive to both temperature and precipitation changes. When the model is run using the UKCIP02 climate projections for the time periods 2011–2040, 2041–2070 and 2071–2100, the geographical distribution of blanket peatlands gradually retreats towards the north and the west. In the UKCIP02 high emissions scenario for 2071–2100, the blanket peatland bioclimatic space is ~84% smaller than contemporary conditions (1961–1990); only parts of the west of Scotland remain inside this space. Increasing summer temperature is the main driver of the projected changes in areal extent. Simulations using 7 climate model outputs resulted in generally similar patterns of declining aereal extent of the bioclimatic space, although differing in degree. The results presented in this study should be viewed as a first step towards understanding the trends likely to affect the blanket peatland distribution in Great Britain. The eventual fate of existing blanket peatlands left outside their bioclimatic space remains uncertain.

Concepção, desenvolvimento e validação de instrumentos de coleta de dados para estudar a percepção do processo decisório e as diferenças culturais

A presente dissertação insere-se no contexto de um projeto global de pesquisa, em desenvolvimento no GESID-PPGA/EA/UFRGS, com a cooperação de algumas universidades estrangeiras. Tal projeto tem como tema a percepção do processo decisório individual e a influência da cultura nacional e da experiência decisória. Para estudar a inter-relação destes assuntos é preciso, antes de mais nada, elaborar um conjunto de instrumentos que permitam investigar a percepção das pessoas sobre a tomada de decisão. Este é o objetivo principal do presente trabalho, que refere-se à primeira fase desse projeto global: a partir da literatura, e do conhecimento de um grupo de pesquisadores, conceber e desenvolver um conjunto de instrumentos (quantitativos e qualitativos) válidos para estudar a decisão. E ainda estabelecer uma metodologia de aplicação desse instrumental, a qual possa determinar uma seqüência (ordem) e forma de aplicação mais adequada. Para tanto, primeiramente foram definidas as 3 questões de pesquisa, que nortearam o desenvolvimento dos instrumentos de pesquisa, as quais deverão ser investigadas no contexto do projeto global de pesquisa, e que podem ser resumidas da seguinte forma: (1) Independentemente da cultura nacional ou do nível de experiência decisória dos indivíduos é possível identificar fatores comuns (passos, princípios, insights) a respeito da forma como as pessoas percebem o processo decisório individual, especialmente se tomado o modelo de processo decisório da “Racionalidade limitada” de Simon (1947) como padrão de comparação? (2) A cultura atua como fator de diferenciação na percepção do processo decisório individual? (3) A Experiência Decisória (vivência) dos indivíduos influencia a forma como eles percebem o processo decisório individual? A definição destas 3 questões de pesquisa possibilitou a concepção dos instrumentos, nos quais posteriormente foi realizada uma validação de conteúdo (por uma comissão de juízes) e de sua seqüência de aplicação (testando-se diferentes ordens), bem como a verificação da sua fidedignidade (através do Teste-reteste). Com este processo obteve-se os seguintes resultados: (1) projeto global consolidado; (2) conjunto de instrumentos de pesquisa concebido e validado; (3) seqüência de aplicação do instrumental definida e validada; (4) quadro de construtos definido fornecendo subsídios para a definição de um protocolo de análise de dados; (5) concepção de um método para verificação da "contaminação" de instrumentos de pesquisa.

Incerteza e dívida pública prefixada no Brasil

This study analyses the bids¿ dispersion in fixed income government securities auctions issued by the National Treasury of Brazil. We try to estimate the bids¿ variance based on factors that may forecast its movement. We hope to help the security issuer by offering more data before the auction. The basic idea is to relate the market uncertainty with the primary auction of government securities. Results indicates the importance of uncertainty on the bidding decisions. It shows also the need for a liquid secondary market to the selling of long-term fixed income securities.