Baseline evaluation of environmental physical activity and nutrition support of Texas Medical Center hospital worksites

Background: Obesity is a major health problem in the United States that has reached epidemic proportions. With most U.S adults spending the majority of their waking hours at work, the influence of the workplace environment on obesity is gaining in importance. Recent research implicates worksites as providing an 'obesogenic' environment as they encourage overeating and reduce the opportunity for physical activity. Objective: The aim of this study is to describe the nutrition and physical activity environment of Texas Medical Center (TMC) hospitals participating in the Shape Up Houston evaluation study to develop a scoring system to quantify the environmental data collected using the Environmental Assessment Tool (EAT) survey and to assess the inter-observer reliability of using the EAT survey. Methods: A survey instrument that was adapted from the Environmental Assessment Tool (EAT) developed by Dejoy DM et al in 2008 to measure the hospital environmental support for nutrition and physical activity was used for this study. The inter-observer reliability of using the EAT survey was measured and total percent agreement scores were computed. Most responses on the EAT survey are dichotomous (Yes and No) and these responses were coded with a '0' for a 'no' response and a '1' for a 'yes' response. A summative scoring system was developed to quantify these responses. Each hospital was given a score for each scale and subscale on the EAT survey in addition to a total score. All analyses were conducted using Stata 11 software. Results: High inter-observer reliability is observed using EAT. The percentage agreement scores ranged from 94.4%–100%. Only 2 of the 5 hospitals had a fitness facility onsite and scores for exercise programs and outdoor facilities available for hospital employees ranged from 0–62% and 0–37.5%, respectively. The healthy eating percentage for hospital cafeterias range from 42%–92% across the different hospitals while the healthy vending scores were 0%–40%. The total TMC 'healthy hospital' score was 49%. Conclusion: The EAT survey is a reliable instrument for measuring the physical activity and nutrition support environment of hospital worksites. The study results showed a large variability among the TMC hospitals in the existing physical activity and nutrition support environment. This study proposes cost effective policy changes that can increase environmental support to healthy eating and active living among TMC hospital employees.^

Volumetric Modulated Arc Therapy Evaluation with the Radiological Physics Center Head and Neck Phantom

Validation of treatment plan quality and dose calculation accuracy is essential for new radiotherapy techniques, including volumetric modulated arc therapy (VMAT). VMAT delivers intensity modulated radiotherapy treatments while simultaneously rotating the gantry, adding an additional level of complexity to both the dose calculation and delivery of VMAT treatments compared to static gantry IMRT. The purpose of this project was to compare two VMAT systems, Elekta VMAT and Varian RapidArc, to the current standard of care, IMRT, in terms of both treatment plan quality and dosimetric delivery accuracy using the Radiological Physics Center (RPC) head and neck (H&N) phantom. Clinically relevant treatment plans were created for the phantom using typical prescription and dose constraints for Elekta VMAT (planned with Pinnacle3 Smart Arc) and RapidArc and IMRT (both planned with Eclipse). The treatment plans were evaluated to determine if they were clinically comparable using several dosimetric criteria, including ability to meet dose objectives, hot spots, conformity index, and homogeneity index. The planned treatments were delivered to the phantom and absolute doses and relative dose distributions were measured with thermoluminescent dosimeters (TLDs) and radiochromic film, respectively. The measured and calculated doses of each treatment were compared to determine if they were clinically acceptable based upon RPC criteria of ±7% dose difference and 4 mm distance-to-agreement. Gamma analysis was used to assess dosimetric accuracy, as well. All treatment plans were able to meet the dosimetric objectives set by the RPC and had similar hot spots in the normal tissue. The Elekta VMAT plan was more homogenous but less conformal than the RapidArc and IMRT plans. When comparing the measured and calculated doses, all plans met the RPC ±7%/4 mm criteria. The percent of points passing the gamma analysis for each treatment delivery was acceptable. Treatment plan quality of the Elekta VMAT, RapidArc and IMRT treatments were comparable for consistent dose prescriptions and constraints. Additionally, the dosimetric accuracy of the Elekta VMAT and RapidArc treatments was verified to be within acceptable tolerances.

A simulation study of the effects of small center enrollment in multi -center clinical trials

Multi-center clinical trials are very common in the development of new drugs and devices. One concern in such trials, is the effect of individual investigational sites enrolling small numbers of patients on the overall result. Can the presence of small centers cause an ineffective treatment to appear effective when treatment-by-center interaction is not statistically significant?^ In this research, simulations are used to study the effect that centers enrolling few patients may have on the analysis of clinical trial data. A multi-center clinical trial with 20 sites is simulated to investigate the effect of a new treatment in comparison to a placebo treatment. Twelve of these 20 investigational sites are considered small, each enrolling less than four patients per treatment group. Three clinical trials are simulated with sample sizes of 100, 170 and 300. The simulated data is generated with various characteristics, one in which treatment should be considered effective and another where treatment is not effective. Qualitative interactions are also produced within the small sites to further investigate the effect of small centers under various conditions.^ Standard analysis of variance methods and the "sometimes-pool" testing procedure are applied to the simulated data. One model investigates treatment and center effect and treatment-by-center interaction. Another model investigates treatment effect alone. These analyses are used to determine the power to detect treatment-by-center interactions, and the probability of type I error.^ We find it is difficult to detect treatment-by-center interactions when only a few investigational sites enrolling a limited number of patients participate in the interaction. However, we find no increased risk of type I error in these situations. In a pooled analysis, when the treatment is not effective, the probability of finding a significant treatment effect in the absence of significant treatment-by-center interaction is well within standard limits of type I error. ^

Gestión de la mano de obra, flexibilidad y precariedad en el sector comercio : Heterogeneidad de situaciones. Un análisis en los shopping center

En esta ponencia presentamos un primer acercamiento exploratorio en el sector comercio. Concretamente, y a partir del análisis de un subsector -shopping centers-, buscamos observar cuestiones vinculadas con las estrategias de flexibilidad laboral, precariedad y subcontratación a través del estudio de las modalidades de gestión de mano de obra que allí operan. Para ello, analizamos algunas de las formas contractuales y las condiciones de trabajo que se presentan en un sector caracterizado por la heterogeneidad de los actores, la multiplicidad de actividades y el relevante lugar que ocupa en la economía argentina. La elección del sector mercantil parte de considerar las grandes transformaciones que la actividad ha experimentado a lo largo de su historia. E0sto se debe, entre otros factores, a los cambios económicos y sociales que impactaron directamente en las actividades comerciales. Y, a su vez, incidieron en la composición de los trabajadores y en la organización del trabajo que integran el sector. Dada la complejidad de la actividad seleccionada, distinguimos para el análisis del presente trabajo el subsector centros de compras (shopping centers). En primer lugar, nos proponemos una presentación general del sector comercio. Luego, nos focalizaremos en el subsector seleccionado a fin de identificar las principales características que operan en él

Christos C. Tsagalis. The Oral Palimsest. Exploring Intertextuality in the Homeric Epics. Center for Hellenic Studies, Harvard University Press, Cambridge, Massachusetts, and London, England, 2008, ix+325 pp.

Fil: Zecchin de Fasano, Graciela Cristina. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Christos C. Tsagalis. The Oral Palimsest. Exploring Intertextuality in the Homeric Epics. Center for Hellenic Studies, Harvard University Press, Cambridge, Massachusetts, and London, England, 2008, ix+325 pp.

Fil: Zecchin de Fasano, Graciela Cristina. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Gestión de la mano de obra, flexibilidad y precariedad en el sector comercio : Heterogeneidad de situaciones. Un análisis en los shopping center

En esta ponencia presentamos un primer acercamiento exploratorio en el sector comercio. Concretamente, y a partir del análisis de un subsector -shopping centers-, buscamos observar cuestiones vinculadas con las estrategias de flexibilidad laboral, precariedad y subcontratación a través del estudio de las modalidades de gestión de mano de obra que allí operan. Para ello, analizamos algunas de las formas contractuales y las condiciones de trabajo que se presentan en un sector caracterizado por la heterogeneidad de los actores, la multiplicidad de actividades y el relevante lugar que ocupa en la economía argentina. La elección del sector mercantil parte de considerar las grandes transformaciones que la actividad ha experimentado a lo largo de su historia. E0sto se debe, entre otros factores, a los cambios económicos y sociales que impactaron directamente en las actividades comerciales. Y, a su vez, incidieron en la composición de los trabajadores y en la organización del trabajo que integran el sector. Dada la complejidad de la actividad seleccionada, distinguimos para el análisis del presente trabajo el subsector centros de compras (shopping centers). En primer lugar, nos proponemos una presentación general del sector comercio. Luego, nos focalizaremos en el subsector seleccionado a fin de identificar las principales características que operan en él

Gestión de la mano de obra, flexibilidad y precariedad en el sector comercio : Heterogeneidad de situaciones. Un análisis en los shopping center

En esta ponencia presentamos un primer acercamiento exploratorio en el sector comercio. Concretamente, y a partir del análisis de un subsector -shopping centers-, buscamos observar cuestiones vinculadas con las estrategias de flexibilidad laboral, precariedad y subcontratación a través del estudio de las modalidades de gestión de mano de obra que allí operan. Para ello, analizamos algunas de las formas contractuales y las condiciones de trabajo que se presentan en un sector caracterizado por la heterogeneidad de los actores, la multiplicidad de actividades y el relevante lugar que ocupa en la economía argentina. La elección del sector mercantil parte de considerar las grandes transformaciones que la actividad ha experimentado a lo largo de su historia. E0sto se debe, entre otros factores, a los cambios económicos y sociales que impactaron directamente en las actividades comerciales. Y, a su vez, incidieron en la composición de los trabajadores y en la organización del trabajo que integran el sector. Dada la complejidad de la actividad seleccionada, distinguimos para el análisis del presente trabajo el subsector centros de compras (shopping centers). En primer lugar, nos proponemos una presentación general del sector comercio. Luego, nos focalizaremos en el subsector seleccionado a fin de identificar las principales características que operan en él

Major and trace element composition of melts from the Gorely volcanic center, southern Kamchatka

Melt inclusions in olivine and plagioclase phenocrysts from rocks (magnesian basalt, basaltic andesite, andesite, ignimbrite, and dacite) of various age from the Gorely volcanic center, southern Kamchatka, were studied by means of their homogenization and by analyzing the glasses in 100 melt inclusions on an electron microprobe and 24 inclusions on an ion probe. The SiO2 concentrations of the melts vary within a broad range of 45-74 wt%, as also are the concentrations of other major components. According to their SiO2, Na2O, K2O, TiO2, and P2O5 concentrations, the melts are classified into seven groups. The mafic melts (45-53 wt% SiO2) comprise the following varieties: potassic (on average 4.2 wt% K2O, 1.7 wt% Na2O, 1.0 wt% TiO2, and 0.20 wt% P2O5), sodic (3.2% Na2O, 1.1% K2O, 1.1% TiO2, and 0.40% P2O5), and titaniferous with high P2O5 concentrations (2.2% TiO2, 1.1% P2O5, 3.8% Na2O, and 3.0% K2O). The melts of intermediate composition (53-64% SiO2) also include potassic (5.6% K2O, 3.4% Na2O, 1.0% TiO2, and 0.4% P2O5) and sodic (4.3% Na2O, 2.8% K2O, 1.3% TiO2, and 0.4% P2O5) varieties. The acid melts (64-74% SiO2) are either potassic (4.5% K2O, 3.6% Na2O, 0.7% TiO2, and 0.15% P2O5) or sodic (4.5% Na2O, 3.1% K2O, 0.7% TiO2, and 0.13% P2O5). A distinctive feature of the Gorely volcanic center is the pervasive occurrence of K-rich compositions throughout the whole compositional range (silicity) of the melts. Melt inclusions of various types were sometimes found not only in a single sample but also in the same phenocrysts. The sodic and potassic types of the melts contain different Cl and F concentrations: the sodic melts are richer in Cl, whereas the potassic melts are enriched in F. We are the first to discover potassic melts with very high F concentrations (up to 2.7 wt%, 1.19 wt% on average, 17 analyses) in the Kuriles and Kamchatka. The average F concentration in the sodic melts is 0.16 wt% (37 analyses). The melts are distinguished for their richness in various groups of trace elements: LILE, REE (particularly HREE), and HFSE (except Nb). All of the melts share certain geochemical features. The concentrations of elements systematically increase from the mafic to acid melts (except only for the Sr and Eu concentrations, because of active plagioclase fractionation, and Ti, an element contained in ore minerals). The paper presents a review of literature data on volcanic rocks in the Kurile-Kamchatka area in which melt inclusions with high K2O concentrations (K2O/Na2O > 1) were found. K-rich melts are proved to be extremely widespread in the area and were found on such volcanoes as Avachinskii, Bezymyannyi, Bol'shoi Semyachek, Dikii Greben', Karymskii, Kekuknaiskii, Kudryavyi, and Shiveluch and in the Valaginskii and Tumrok Ranges.