863 research outputs found

    Proposed pre-penance catechesis for the mentally retarded at the pre-operational stage

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    ...The writer set about to develop a pre-penance catechesis for mentally retarded children. It was proposed that a set of lessons at the preoperative stage could be developed, aimed at fostering a more refined sense of morality as reflected in gratitude responses

    Sulfur degassing at Erta Ale (Ethiopia) and Masaya (Nicaragua) volcanoes: Implications for degassing processes and oxygen fugacities of basaltic systems

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    We investigate the relationship between sulfur and oxygen fugacity at Erta Ale and Masaya volcanoes. Oxygen fugacity was assessed utilizing Fe 3+/ΣFe and major element compositions measured in olivine-hosted melt inclusions and matrix glasses. Erta Ale

    Sulfur degassing at Erta Ale (Ethiopia) and Masaya (Nicaragua) volcanoes: Implications for degassing processes and oxygen fugacities of basaltic systems

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    We investigate the relationship between sulfur and oxygen fugacity at Erta Ale and Masaya volcanoes. Oxygen fugacity was assessed utilizing Fe3+/∑Fe and major element compositions measured in olivine‐hosted melt inclusions and matrix glasses. Erta Ale melts have Fe3+/∑Fe of 0.15–0.16, reflecting fO2 of ΔQFM 0.0 ± 0.3, which is indistinguishable from fO2 calculated from CO2/CO ratios in high‐temperature gases. Masaya is more oxidized at ΔQFM +1.7 ± 0.4, typical of arc settings. Sulfur isotope compositions of gases and scoria at Erta Ale (δ34Sgas − 0.5‰; δ34Sscoria + 0.9‰) and Masaya (δ34Sgas + 4.8‰; δ34Sscoria + 7.4‰) reflect distinct sulfur sources, as well as isotopic fractionation during degassing (equilibrium and kinetic fractionation effects). Sulfur speciation in melts plays an important role in isotope fractionation during degassing and S6+/∑S is 0.67 in Masaya melt inclusions. No change is observed in Fe3+/∑Fe or S6+/∑S with extent of S degassing at Erta Ale, indicating negligible effect on fO2, and further suggesting that H2S is the dominant gas species exsolved from the S2−‐rich melt (i.e., no redistribution of electrons). High SO2/H2S observed in Erta Ale gas emissions is due to gas re‐equilibration at low pressure and fixed fO2. Sulfur budget considerations indicate that the majority of S injected into the systems is emitted as gas, which is therefore representative of the magmatic S isotope composition. The composition of the Masaya gas plume (+4.8‰) cannot be explained by fractionation effects but rather reflects recycling of high δ34S oxidized sulfur through the subduction zone

    Impaired Collateral Recruitment and Outward Remodeling in Experimental Diabetes

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    OBJECTIVE—In this study, the effect of chronic hyperglycemia on acute ligation-induced collateral vasodilation, on monocyte chemotaxis, and on structural outward remodeling of collaterals was investigated

    Homocysteine levels in preterm infants: is there an association with intraventricular hemorrhage? A prospective cohort study.

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    BACKGROUND: The purpose of this study was to characterize total homocysteine (tHcy) levels at birth in preterm and term infants and identify associations with intraventricular hemorrhage (IVH) and other neonatal outcomes such as mortality, sepsis, necrotizing enterocolitis, bronchopulmonary dysplasia, and thrombocytopenia. METHODS: 123 infants \u3c 32 weeks gestation admitted to our Level III nursery were enrolled. A group of 25 term infants were enrolled for comparison. Two blood spots collected on filter paper with admission blood drawing were analyzed by a high performance liquid chromatography (HPLC) method. Statistical analysis included ANOVA, Spearman\u27s Rank Order Correlation and Mann-Whitney U test. RESULTS: The median tHcy was 2.75 micromol/L with an interquartile range of 1.34 - 4.96 micromol/L. There was no difference between preterm and term tHcy (median 2.76, IQR 1.25 - 4.8 micromol/L vs median 2.54, IQR 1.55 - 7.85 micromol/L, p = 0.07). There was no statistically significant difference in tHcy in 31 preterm infants with IVH compared to infants without IVH (median 1.96, IQR 1.09 - 4.35 micromol/L vs median 2.96, IQR 1.51 - 4.84 micromol/L, p = 0.43). There was also no statistically significant difference in tHcy in 7 infants with periventricular leukomalacia (PVL) compared to infants without PVL (median 1.55, IQR 0.25 - 3.45 micromol/L vs median 2.85, IQR 1.34 - 4.82 micromol/L, p = 0.07). Male infants had lower tHcy compared to female; prenatal steroids were associated with a higher tHcy. CONCLUSION: In our population of preterm infants, there is no association between IVH and tHcy. Male gender, prenatal steroids and preeclampsia were associated with differences in tHcy levels

    Monitoreo de procesos de ecológicos del Bosque Seco Tropical: Aplicaciones de sensores remotos para estimaciones a nivel de paisaje y el cambio global

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    Proyecto de Investigación. y extensión (Código VIE: 5402-1401-1012) Instituto Tecnológico de Costa Rica. Vicerrectoría de Investigación y Extensión (VIE). Escuela de Ingeniería Forestal; Alberta University, Canadá; University of Wisconsin; University of Virginia; Universidad Nacional Autónoma de México; Instituto Venezolano de Investigaciones Científicas; Agencia de Medio Ambiente. Cuba; Universidad Estatal de Belo Horizonte. Brasil; Universidad de Montes Claros. Brasil; Universidad de Pernambuco. Brasil; Universidad Estatal de Río de Janeiro. Brasil, 2014Este proyecto se encadenó al proyecto ya concluido "Dimensiones humanas, ecológicas y biofísicas de los bosques secos tropicales (código VIE 5402-1401-9001)". Durante su ejecución fue posible dar continuidad al análisis de datos y preparación de publicaciones científicas y académicas pendientes como fenología, dinámica de hojarasca, tasas de crecimiento, mortalidad y reingreso en el bosque seco tropical. También el proyecto trabajo en la preparación de artículos que integran los resultados de tres países: México, Costa Rica y Brasil. Así mismo se continuó con las mediciones de campo de las parcelas y procesos ecológicos para crear una base de datos robusta, actualmente y después de 10 años, estas bases permiten modelar los efectos de cambios climáticos en el comportamiento de los procesos ecológicos de los bosques secos tropicales (Bst). El elemento novedoso de este proyecto fue la instalación de torres de fenología por medio de financiamiento externo y que miden sobre el dosel del bosques seco tropical los cambios temporales de la radiación de onda corta y onda larga, tanto de entrada como de salida. Los cambios en la reflectancia de las hojas se relacionan tanto con el ángulo del sol (que podemos corregir automáticamente) como con la biomasa de hojas. Las torres permiten la colección de datos de campo a cada 15 minutos y estos datos se pueden calibrar con los índices de reflectancia de varios sensores espaciales. Una buena calibración para los diferentes tipos de bosques secos tropicales (las torres operan en Brasil, México y Costa Rica) puede permitir hacer simulaciones del efecto del cambio climático en la productividad de los bosques, su impacto en el ciclo del agua y por ende en las capacidades de fijar carbono. Además, el proyecto fue capaz de instalar una torre con equipo altamente especializado que permite determinar los flujos de CO2 y de vapor de agua del bosque seco tropical mediante la técnica de Covarianza de Flujos Turbulentos. Asociada a esta torre de 22 metros se estableció una parcela de una hectárea que permite caracterizar la huella de CO2 del ecosistema de forma más precisa. Esta hectárea permitirá mejorar la clasificación de imágenes satelitales y aéreas, así como también facilitara el uso de sensores remotos y otras técnicas de teledetección. Desde la perspectiva de los recursos naturales, se aplicó un protocolo comprensivo y estandarizado para reconocer y comparar las clasificaciones espaciales de los Bst, la estructura y composición florística de sus etapas sucesionales, dinámica de la hojarasca, fenología y tasas de crecimiento. Desde la perspectiva de las ciencias sociales, el trabajo que se realizó fue innovador dado que se crearon vínculos con el gobierno, los científicos y las comunidades. Se estudió las interacciones de las comunidades vecinas con los Bst, así como los factores socioeconómicos, políticos y legales que controlan su conservación y manejo. El proyecto fue capaz de generar la siguiente producción académica y científica: 9 artículos indexados, 2 artículos en español, 5 capítulos en libros en inglés, 1 capitulo en un enciclopedia, 20 ponencias en evento nacional, 6 ponencias en eventos internacionales, 10 artículos en borrador, 5 Tesis de pregrado y 2 Tesis de Doctorado. En medios de comunicación, el proyecto decidió ser más austero debido al alto valor de los equipos instalados en el Parque Nacional Santa Rosa para así no llamar la atención para provocar los robos o daños, sin embargo fue posible generar 7 publicaciones en medios impresos/Web y una intervención en radio nacional. En cuanto a la participación de talleres de incidencia política fueron organizados 3 talleres con decisores sobre el estado de los bosques secos en Costa Rica y sobre el potencial de trabajo conjunto entre organizaciones y el proyecto de investigación. Además se organizó una sesión de Simposio en el Congreso indexado de la ATBC y la OET en el año 2013. Adicionalmente se participó en otros 5 talleres organizados por otras instituciones. En total el proyecto recibió y entrenó a 29 estudiantes, de los cuales 9 fueron extranjeros y 20 del TEC, los cuales trabajaron como asistentes de laboratorio y campo entrenándose en el uso de instrumentos, montaje y medición de diseños experimentales, colección y procesamiento de datos y muestras. Actualmente se cuenta con una base de datos de crecimiento de 10 años, así como 4 años de datos de torres de fenología y 1 año y 3 meses de datos de flujos de carbono y vapor de agua, los cuales continuaran siendo analizados en la siguiente etapa del proyecto (código VIE 5402-1401-1028).Instituto Tecnológico de Costa Rica

    Father's occupational exposure to carcinogenic agents and childhood acute leukemia: a new method to assess exposure (a case-control study)

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    <p>Abstract</p> <p>Background</p> <p>Medical research has not been able to establish whether a father's occupational exposures are associated with the development of acute leukemia (AL) in their offspring. The studies conducted have weaknesses that have generated a misclassification of such exposure. Occupations and exposures to substances associated with childhood cancer are not very frequently encountered in the general population; thus, the reported risks are both inconsistent and inaccurate. In this study, to assess exposure we used a new method, an exposure index, which took into consideration the industrial branch, specific position, use of protective equipment, substances at work, degree of contact with such substances, and time of exposure. This index allowed us to obtain a grade, which permitted the identification of individuals according to their level of exposure to known or potentially carcinogenic agents that are not necessarily specifically identified as risk factors for leukemia. The aim of this study was to determine the association between a father's occupational exposure to carcinogenic agents and the presence of AL in their offspring.</p> <p>Methods</p> <p>From 1999 to 2000, a case-control study was performed with 193 children who reside in Mexico City and had been diagnosed with AL. The initial sample-size calculation was 150 children per group, assessed with an expected odds ratio (OR) of three and a minimum exposure frequency of 15.8%. These children were matched by age, sex, and institution with 193 pediatric surgical patients at secondary-care hospitals. A questionnaire was used to determine each child's background and the characteristics of the father's occupation(s). In order to determine the level of exposure to carcinogenic agents, a previously validated exposure index (occupational exposure index, OEI) was used. The consistency and validity of the index were assessed by a questionnaire comparison, the sensory recognition of the work area, and an expert's opinion.</p> <p>Results</p> <p>The adjusted ORs and 95% confidence intervals (CI) were 1.69 (0.98, 2.92) during the preconception period; 1.98 (1.13, 3.45) during the index pregnancy; 2.11 (1.17, 3.78) during breastfeeding period; 2.17 (1.28, 3.66) after birth; and 2.06 (1.24, 3.42) for global exposure.</p> <p>Conclusion</p> <p>This is the first study in which an OEI was used to assess a father's occupational exposure to carcinogenic agents as a risk factor for the development of childhood AL in his offspring. From our results, we conclude that children whose fathers have been exposed to a high level of carcinogenic agents seem to have a greater risk of developing acute leukemia. However, confounding factors cannot be disregarded due to an incomplete control for confounding.</p

    Unravelling causal and temporal influences underpinning monitoring systems success: a typological approach

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    This paper is concerned with the causal and temporal underpinnings of Information Systems (IS) success. It uses a typological approach based on fuzzy-set Qualitative Comparative Analysis (fsQCA) and process tracing. It investigates success across multiple cases of IS adopted for monitoring the disbursement and use of resources within the European Social Fund (ESF). The study unravels the causal mechanisms and temporal pathways underpinning success in these systems. It develops a typological theory of monitoring systems success that reveals the temporal pathways embedded within individual cases, as well as broader theoretical patterns emerging across cases. Theoretical, methodological and practical implications are discussed

    Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathy

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    <p>Abstract</p> <p>Background</p> <p>Breast cancers are more frequently diagnosed at an early stage and currently have improved long term outcomes. Late normal tissue complications induced by adjuvant radiotherapy like secondary cancers or cardiomyopathy must now be avoided at all cost. Several new breast radiotherapy techniques have been developed and this work aims at comparing the scatter doses of internal organs for those techniques.</p> <p>Methods</p> <p>A CT-scan of a typical early stage left breast cancer patient was used to describe a realistic anthropomorphic phantom in the MCNP Monte Carlo code. Dose tally detectors were placed in breasts, the heart, the ipsilateral lung, and the spleen. Five irradiation techniques were simulated: whole breast radiotherapy 50 Gy in 25 fractions using physical wedge or breast IMRT, 3D-CRT partial breast radiotherapy 38.5 Gy in 10 fractions, HDR brachytherapy delivering 34 Gy in 10 treatments, or Permanent Breast <sup>103</sup>Pd Seed Implant delivering 90 Gy.</p> <p>Results</p> <p>For external beam radiotherapy the wedge compensation technique yielded the largest doses to internal organs like the spleen or the heart, respectively 2,300 mSv and 2.7 Gy. Smaller scatter dose are induced using breast IMRT, respectively 810 mSv and 1.1 Gy, or 3D-CRT partial breast irradiation, respectively 130 mSv and 0.7 Gy. Dose to the lung is also smaller for IMRT and 3D-CRT compared to the wedge technique. For multicatheter HDR brachytherapy a large dose is delivered to the heart, 3.6 Gy, the spleen receives 1,171 mSv and the lung receives 2,471 mSv. These values are 44% higher in case of a balloon catheter. In contrast, breast seeds implant is associated with low dose to most internal organs.</p> <p>Conclusions</p> <p>The present data support the use of breast IMRT or virtual wedge technique instead of physical wedges for whole breast radiotherapy. Regarding partial breast irradiation techniques, low energy source brachytherapy and external beam 3D-CRT appear safer than <sup>192</sup>Ir HDR techniques.</p
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