bluuebunny/crossref_metadata_2025 huggingface dataset:
Pabellón polideportivo cubierto en Cuéllar/ Segovia/España
Authors: Olmos Martínez Pedro J. , Pantaleón Prieto Marcos J.
Published: April 2013

El presente trabajo pretende mostrar los criterios y adoptados para llevar a cabo el proyecto y ejecución de un pabellón cubierto para 1.000 espectadores, en Cuéllar, con tres objetivos básicos: seguridad, funcionalidad y economía.
Prefabricación y elevación de placas de hormigón armado en grandes chimeneas industriales
Authors: Del Solar Bermejo José
Published: April 2013

Las chimeneas proyectadas y construidas en los últimos años en España, se consideran de acuerdo al modelo de chimeneas con una cámara ventilada y accesible entre el conducto cerámico y el fuste de hormigón.
El conducto se construye normalmente por tramos. Cada tramo apoya en placas de hormigón armado soportadas por ménsulas del fuste.
Tradicionalmente estas placas de hormigón han sido construidas in situ con auxilio de una plataforma auxiliar suspendida de la coronación de la chimenea.
En el método desarrollado por Karman y Agromán, las placas son prefabricadas, una sobre otra, en el suelo de la chimenea y después son elevadas hasta su nivel definitivo apoyándolas en las ménsulas del fuste.
En este artículo se trata de describir nuestras experiencias en este campo, asi como los resultados obtenidos con este método de construcción.
Normativa
Authors: Editorial Equipo
Published: April 2013

No disponible.
Castillo
Authors: Marín Sánchez Juan Luis , Moreno Cobedo Sergio , Del Pozo Benito José Luis , Salazar Jiménez Antonio
Published: April 2013

No disponible.
Casa Fanlo
Authors: Gutiérrez Morales Francisco , De Pablo Ortega Miguel Ángel , Rodenas Moreno Fernando , San Vicente Aguirreurreta Gemma , Serrano Marcos Carlos
Published: April 2013

No disponible.
La estructura resistente de los edificios altos
Authors: Manterola Armisen Javier
Published: April 2013

Si consideramos únicamente el problema resistente, un edificio alto podría considerarse como una gran ménsula vertical. Las exigencias resistentes de esta gran ménsula son más apremiantes conforme el edificio crece en altura y su acoplamiento a las necesidades funcionales del edificio más difícil. En este artículo se pasa revista a las diversas tipologías resistentes, desde la estructura aporticada normal de los edificios de altura moderada hasta el "tubo en el tubo" y estructuras laminares totales correspondientes a los más altos edificios construidos y por construir. Se hace un análisis de la forma de resistir de cada una de las tipologías ilustrándolas con ejemplos de edificios construidos.
Fractura del hormigón en régimen no lineal. Intentos para medir la energía de fractura GF
Authors: Planas Jaime , Elices Manuel
Published: April 2013

El propósito de este artículo es doble: presentar un modelo de fractura no lineal y analizar la metodología seguida para medir GF.
El principal inconveniente para aplicar la mecánica de la fractura en régimen elástico y lineal al hormigón, reside en la naturaleza de la zona de fractura. Para superar esta dificultad se ha desarrollado el modelo de la fisura con cohesión, que se presenta y analiza en este trabajo. Este modelo se ha utilizado para deducir la influencia del tamaño en la carga de rotura, habiéndose obtenido resultados similares a los de Bazant.
A pesar de los numerosos experimentos sobre fractura de hormigones todavía no está claro cómo medir GF. En este artículo se analizan los fundamentos teóricos de estos métodos y se hace un estudio crítico de los resultados obtenidos por los autores siguiendo los métodos propuestos por la RILEM y por Bazant.
S3c, prototipos de vivienda construidos por componentes compatibles
Authors: Reyes González J. Miguel
Published: April 2013

¿Qué es la construcción por componentes compatibles?
¿En qué consiste?
¿Cuáles son sus planteamientos?
¿Qué resultados y respuestas aporta?
¿Qué consecuencias e implicaciones conlleva?
A estas y otras cuestiones relacionadas con el tema tratan de dar respuesta estas páginas, pero recurriendo para ello no a definiciones y generalidades que podrían sucumbir en el mundo de las disquisiciones teóricas, sino haciendo referencia a prototipos y proyectos concretos de vivienda realizados en la última década que servirán para, a partir de su descripción, exponer las particulares condiciones que de los mismos se desprenden:
— Metodológicas: ''órdenes abiertos".
— Tecnológicas: ''componentes compatibles".
— De mercado: "prefabricación abierta".
— Transformación: ¿actualización?
XII congreso internacional de la vivienda/Chile
Authors: Escorihuela M. José
Published: April 2013

En este artículo se resume el desarrollo del XII Congreso Internacional de la Vivienda, celebrado en Viña del Mar (Chile), en marzo de 1985, y que ha tenido como tema central: "Nuevos Métodos de Construcción y Financiamiento".
Los trabajos presentados han tratado de dar soluciones técnicas, sociales y financieras al problema de la vivienda, especialmente en los países en desarrollo.
La participación española ha consistido en dos trabajos, uno sobre la problemática concreta de las condensaciones en interiores de muros, y otro que expone un método gráfico que permite simplificar los procesos para adquirir mayor conocimiento de la radiación solar recibida sobre los distintos elementos de un edificio, con el fin de conseguir un mejor aprovechamiento de este tipo de energía y así obtener un mayor confort en el habitat humano.
Iglesia parroquial de la virgen de la consolación en Sassuolo de Modena (Italia)
Authors: Manfredini Enea , Casali Clito
Published: April 2013

La iglesia, realizada en el Norte de la ciudad e insertada en un magnifico parque secular, tiene una estructura enteramente de hormigón armado visto. La cubierta, independiente de la articulación de los espacios internos, consiste en una planta cuadrada con una abertura central. Cuatro columnas circulares sostienen las cuatro vigas principales sobre las cuales se sitúan, a cortos intervalos, las ménsulas de hormigón armado de ancho constante y de altura variable. Una banda alta acristalada entre el paramento perimetral externo y la cubierta completan la composición arquitectónica de la obra.
Edificio para la nueva sede social de la empresa nacional de electricidad, S. A. Madrid/España
Authors: Población Eleuterio
Published: April 2013

En el presente artículo se describe detalladamente el proyecto y ejecución del edificio ENDESA, en Madrid, compuesto por dos edificios de doce alturas uno, y dos el otro, unido por un espacio ajardinado.
En céntrica situación ha exigido una especial adaptación a las Ordenanzas Municipales en cuanto a condiciones de volumen y uso.
Entre sus características más notables pueden señalarse IQ sujeción a una red modular, la adecuación del espacio a las actividades que en él se desarrollarán y las soluciones adoptadas para su cerramiento.
Complejo en urbanización Beamonte Vigo/España
Authors: Bar Boo José
Published: April 2013

Este pequeño conjunto de edificios constituye un intento de integración -no adose o superposición o mera decoración tal como Henry Moore opinaba que hacían el 99% de arquitectos- de artes del diseño en el propio de la arquitectura.
Técnica electrodinámica para la medida del módulo de elasticidad de los materiales de construcción. (Equipo puesto a punto en el lETcc para la medida del módulo de elasticidad dinámico)
Authors: Del Olmo César
Published: April 2013

El presente trabajo puede dividirse en dos partes. La primera hace referencia a la utilidad de la medida del módulo de elasticidad dinámico de los materiales de construcción y contiene, además, una introducción del comportamiento elástico general de los materiales y, en particular, del hormigón. La segunda parte comprende una revisión del método de ensayo establecido por las normas, de uso más extendido, para la medida de esta característica; una descripción del equipo adoptado recientemente en el lET con esta finalidad, donde se señalan las novedades introducidas en el mismo; así como el estudio efectuado para la puesta a punto del equipo, que incluye la determinación de la repetibilidad (*) de resultados del ensayo.
El trabajo se articula en los siguientes apartados: 1. - Introducción. 2. - El hormigón como material elástico. 3. - Medida de las características elásticas del hormigón. 4. - Método electrodinámico para la medida del módulo de elasticidad de los materiales de construcción. 4.1. - Fundamento del método. 4.2. - Procedimiento de ensayo. 4.3. - Equipo del lET para la medida del módulo de elasticidad. 4.4. - Puesta a punto del equipo. 4.5. - Método operatorio. - 4.6. - Cálculo del módulo de elasticidad dinámico. 4.7. - Repetibilidad (*) de resultados. 5. - Conclusiones. - 6. - Agradecimiento. 7. - Bibliografía.
Un auditorio al aire libre en la antigua feria del campo en Madrid, España
Authors: Pérez Arroyo Salvador
Published: April 2013

Se presenta en este artículo el escenario y servicios complementarios construidos para acondicionar la Pista de Exposiciones de la Antigua Feria del Campo de Madrid, como recinto para conciertos Pop y otros espectáculos multitudinarios.
Su estudio despierta interés, no sólo por lo reciente de su realización, sino también por la tecnología que para la misma se empleó, tanto por los plazos de ejecución, como por sus singulares y extremas condiciones de uso previstas: soporte de amplias y aparatosas tecnologías contemporáneas de la comunicación.
Entre las peculiaridades que caracterizan el proyecto destacan:
- La solución de acceso y evacuación del público; así como de carga y descarga de mercancías, lo cual exige acondicionamiento del amplio entorno de influencia del recinto: modificación y construcción de edificaciones y pabellones de servicio adyacentes, junto con la jardinería.
- Las dimensiones de los elementos constructivos empleados, que han exigido el continuo estudio y modificación del proyecto a lo largo de su planteamiento en busca de los consabidos óptimos: función - economía - sencillez de planteamiento: 75 m de vano en una viga-puente.
- El proceso de montaje, que exigió una modulación de piezas operativa, exigió a la vez una independencia en la ejecución de los elementos constructivos
Teatro: ¿ilusión? o Tramoya
Authors: Reyes González José Miguel
Published: April 2013

Se describe en este artículo la técnica y procedimientos utilizados actualmente en la construcción de la tramoya teatral. Se les pone en relación y compara con otras construcciones «no teatrales» con las que guardan similitudes e influencias comunes.
Se destacan entre éstas: su ligereza, movilidad y facilidad de manejo para transformar y efectuar operaciones espaciales; y, desde aquí, es desde donde se efectúa su análisis constructivo. Para ello, se repasan tanto los sistemas materiales de construcción escénica (suelos, techos, paredes) como lumínicos y sonoros (diseño acústico y electrónico del «espacio sonoro»). Se pone de manifiesto la importancia de la electrónica en todos ellos, y por tanto en el control del medio ambiente y su manipulación en esta clase de definiciones espaciales, así como su relación con las teorías arquitectónicas de los 60 (Arquitectura-pop, Metabolismo, Megaestructuras, etc.). A lo largo del recorrido por ambas, se aprecia todo un abanico de realizaciones y recursos que hacen posible su aplicación y desarrollo recíproco a cualquier escala.
En definitiva, se trata de valorar la «escena teatral» y sus tecnologías como un posible laboratorio de «experiencia espacial directa», a partir de las siguientes cuestiones:
- ¿Qué definiciones espaciales y soluciones constructivas aporta la tramoya teatral a la experimentación espacial?
- Sus propuestas y soluciones, tanto espaciales como constructivas ¿son el resultado de la cultura y tecnología a que pertenecen?, o por el contrario, ¿generan a partir de sí mismas un continuo laboratorio de experiencias de inmediata aplicación sobre dicha cultura?
- ¿Es el recinto en que la escena se desarrolla, el que la condiciona?, o también por el contrario, ¿la definición espacial de ésta es la que influye sobre aquél?
- En suma: ¿de qué mecanismos y herramientas materiales se vale el teatro para transportarnos al mundo que desde su escena nos propone?
El yeso, un material apropiado para una construcción barata
Authors: Nolhier Marc
Published: April 2013

En este artículo se hace una valoración de las propiedades del yeso en cuanto a resistencia, trabajabilidad y bajo costo con el fin de aplicarlo a una construcción de viviendas baratas en países poco desarrollados.
Basándose en experimentos llevados a cabo en países africanos, se estudia el problema de tecnología, de la adaptación de la mano de obra al proceso de construcción con bloques de yeso prefabricados y de su rentabilidad.
Montaje para una exposición de pintura en el palacio de Villahermosa. Remodelado - Madrid
Authors: Rodríguez de Partearroyo Francisco
Published: April 2013

Se describen en este artículo los trabajos de remodelación del palacio de Villahermosa, con vistas a su integración como parte del complejo del Museo del Prado. El edificio había sido anteriormente acondicionado como sede de una entidad bancaria.
La remodelación ha consistido fundamentalmente en adecuar el interior del edificio para conseguir un ambiente análogo al de las salas del Museo mediante la disposición de muros, revestimientos, etc., capaces de crear dicho ambiente.
Customer loyalty in the South African long-term insurance industry
Authors: Du Plessis Leon , Roberts-Lombard Mornay
Published: April 2013

The primary objective of this study is to investigate the influence of selected independent variables, two-way communication and conflict handling on intentional customer loyalty via Customer Relationship Management (CRM) as the intervening variable within the South African long-term insurance environment. Primary data were gathered using a questionnaire, with items referring to Customer Relationship Management, customer loyalty, two-way communication and conflict handling. The sample consisted of 254 customers in four customer walk-in centres of a long-term insurance provider in South Africa. Data were factor-analysed. One independent variable, conflict handling, exerted a statistically significant positive influence on the intervening variable (CRM), whilst two-way communication exerted a statistically significant negative influence on the intervening variable. This variable (CRM) positively influenced the dependent variable (customer loyalty). If long-term insurance organisations communicate timeously and accurately, and are skilled in conflict handling, greater loyalty will be created amongst customers. The study revealed that the majority of customers (51.53%) strongly agree that two-way communication is an important dimension that underpins Customer Relationship Management and their relationship with a long-term insurance organisation. The empirical results indicate a negative relationship between the perceived two-way communication by a long-term insurance organisation and CRM at the insurance provider in South Africa. In terms of conflict handling, the study revealed that the majority of customers (45.69%) strongly agree that conflict handling is an important dimension that underpins Customer Relationship Management and their relationship with a long-term insurance organisation. The empirical results indicate a positive relationship between perceived conflict handling by a long-term insurance provider and CRM at the organisation in South Africa. Finally, the empirical results indicate a positive relationship between Customer Relationship Management and intentional customer loyalty at a long-term insurance provider in South Africa.
The level of organisational identification amongst students at a post-merged South African university
Authors: Breytenbach Nadia , Renard Michelle , Snelgar Robin
Published: April 2013

Orientation: Organisational  identification  (OI)  refers to individuals  perceiving  that  they belong  to and  are one with  their  organisation.  Limited  research  has  been conducted  on university students’ levels of OI within the South African context.Research purpose: The aim of the study was to determine the level of OI amongst students at a post-merged university in the Eastern Cape Province of South Africa.Motivation for the study: Levels of OI amongst students at a post-merged university could be low, as a result of students not yet adopting the values of the merged university. Yet, no such study has been undertaken at this university since the merger.Research design, approach and method: Mixed methods were used in this study, consisting of qualitative  research  (N = 16)  for  which  focus  group  discussions  were  used,  as  well as quantitative  research  (N =  603)  for  which  an  online questionnaire  was  sent  to  the student sample.Main  findings: The  level  of  OI  amongst  the  students  was found  to  be  high.  Furthermore, students’  race,  campus, university  tenure  and  residence  have  a  significant influence  on students’ levels of OI. Black students identified more with the university than other races and students who studied longer at this university had lower levels of OI. Residence students had a greater level of OI than those who stayed off-campus.Practical/managerial implications: Students should be encouraged to adopt the core values of this university to ensure that OI levels increase. In order to improve OI, university management should  implement  action  plans  for those  student  segments  who  have  exhibited  low  levels of OI.Contribution/value-add: This  research  contributes  to  the current  body  of  knowledge concerning OI which is under-researched within a post-merged university context.
Water footprint of individuals with different diet patterns
Authors: Da Silva Vicente De Paulo Rodrigues , Maracajá Kettrin Farias Bem , De Araújo Lincoln Eloi , Dantas Neto José , Aleixo Danilo De Oliveira , Campos João Hugo Baracuy da Cunha
Published: April 2013

The “water footprint” (WF) concept has been recently introduced as an important indicator of human water consumption. WF is defined as the total volume of water used during the production and consumption of goods and services as well as of direct water consumption by humans. The objective of this work was to use the WF concept to analyze vegetarian and non-vegetarian consumers with different levels of family income. A case study was conducted with residents of Caicó city (Brazil) in order to estimate total amount of water consumed or polluted while producing the goods and services utilized by these consumers. The results indicated that, on average, the WF of the vegetarian consumer represents 58% of non- vegetarian consumers. The WF of the non-vegetarian female consumer was 10-13% smaller than that of the male consumer while for vegetarian consumers the female’s WF was only 5.8% less than the male’s. The WF of the consumer increases linearly with the family income. A population’s water footprint increases as a function of family income and decreases according to eating habits.
Clinical Differentiation of Essential Tremor and Parkinson's Disease
Authors: Fekete Robert , Li Jin
Published: April 2013

We present clinical features and tremor characterization in a patient with Parkinson's disease (PD) as well as in two cases of essential tremor (ET) with some parkinsonian features but no evidence of dopaminergic terminal loss on 123I-FP-CIT Single Photon Emission Computed Tomography (SPECT). Relatively slow frequency rest tremor and bilateral upper extremity bradykinesia without decrementing amplitude were observed in the ET cases, with unilaterally decreased arm swing in case 3. Alternating rest tremor and re-emergent tremor with 13 second latency was confirmed in the PD case. Re-emergent tremor had alternating characteristics, which to our knowledge has not been previously reported. The ET cases had synchronous postural tremor. Alternating re-emergent tremor in PD provides further evidence for re-emergent tremor as an analogue of rest tremor in PD. Two cases of ET with synchronous postural tremor and one to two year history of parkinsonian features had no evidence of dopaminergic terminal loss up to 40 years after the initial onset of ET. Tremor synchronicity characterization can assist in differential diagnosis between the two disorders.
Ruptured Thoracic Aortic Aneurysm Infected with Listeria Monocytogenes: A Case Report and a Review of Literature
Authors: Masuda Shigeki , Takeuchi Nobuhiro , Takada Masanori , Fujita Koichi , Nishibori Yoshiharu , Maruyama Takao
Published: April 2013

A 75-year-old male with a history of alcoholic liver cirrhosis, sigmoid colon cancer, and metastatic liver cancer was admitted to our institution with a complaint of a prickly feeling in his chest. On admission, a chest radiograph revealed a normal cardio-thoracic ratio of 47%. Echocardiography revealed pericardial effusion and blood chemical analyses revealed elevated C-reactive protein levels (14.7 mg/dL). On day 3, chest radiography revealed cardiomegaly with a cardio-thoracic ratio of 58% and protrusion of the left first arch. Contrast-enhanced chest computed tomography revealed a saccular aneurysm in the aortic arch with surrounding hematoma; thus, a ruptured thoracic aortic aneurysm was suspected. Emergency surgery was performed, which revealed a ruptured aortic aneurysm with extensive local inflammation. The diagnosis of an infected aortic rupture was therefore confirmed. The aneurysm and abscess were resected, followed by prosthetic graft replacement and omental packing. Histopathology of the resected aneurysm revealed gram-positive bacilli; and Listeria monocytogenes was confirmed as the causative organism by culture. Postoperative course was uneventful; on postoperative day 60, the patient was ambulatory and was discharged. Here we report the case of a male with a ruptured thoracic aortic aneurysm infected with L. monocytogenes.
Genetic and Shared Environmental Influences on Interferon-γ Production in Response to Mycobacterium tuberculosis Antigens in a Ugandan Population
Authors: Tao Li , Zalwango Sarah , Chervenak Keith , Thiel Bonnie , Malone LaShaunda L. , Qiu Feiyou , Mayanja-Kizza Harriet , Boom W. Henry , Stein Catherine M. , _ _
Published: April 2013

Interferon-γ (IFN-γ) is a key cytokine in the immune response to Mycobacterium tuberculosis (Mtb). Many studies established IFN-γ responses are influenced by host genetics, however differed widely by the study design and heritability estimation method. We estimated heritability of IFN-γ responses to Mtb culture filtrate (CF), ESAT-6, and Antigen 85B (Ag85B) in 1,104 Ugandans from a household contact study. Our method separately evaluates shared environmental and genetic variance, therefore heritability estimates were not upwardly biased, ranging from 11.6% for Ag85B to 22.9% for CF. Subset analyses of individuals with latent Mtb infection or without human immunodeficiency virus infection yielded higher heritability estimates, suggesting 10–30% of variation in IFN-γ is caused by a shared environment. Immunosuppression does not negate the role of genetics on IFN-γ response. These estimates are remarkably close to those reported for components of the innate immune response. These findings have implications for the interpretation of IFN-γ response assays and vaccine studies.
A inadimplência nas instituições de ensino superior: um estudo de caso na instituição XZX
Authors: Herling Luiz Henrique , Moritz Gilberto de Oliveira , Santos Adelcio Machado dos , Soares Thiago Coelho , Back Rafael Bourdot
Published: April 2013

O crescimento do setor da educação superior privada no Brasil harmonizou uma chance para milhares de brasileiros terem acesso ao ensino superior, mas em compensação, surgiu e conjunto com este crescimento, o aumento da inadimplência estudantil. Com a finalidade de pesquisar quais os fatores que condicionam este fato, elaborou-se este Artigo em uma Instituição de Ensino Superior Privada. Averiguo-se que a produção acadêmica a respeito do tema no Brasil é insuficiente. Assim sendo utilizaram-se, como referencial teórico, material bibliográfico e o depoimento de colaboradores ligados a instituição pesquisada. Constatou-se ao decorrer deste artigo que a inadimplência tem relação com fatores pessoais, sócio-econômicos, acadêmicos e institucionais, portanto gerenciáveis. A conjetura de que a inadimplência estudantil está pautada exclusivamente com fatores financeiros não se confirmou.
Proposta de modelo de cadeia de valor para um centro universitário
Authors: Conto Samuel Martim de , Britto João Carlos , Schnorrenberger Adalberto
Published: April 2013

A concorrência é observada em todos os mercados, de maneira especial nos últimos anos também no Ensino Superior. A necessidade de maior profissionalização e competência gerencial nas Instituições de Ensino Superior (IES), proporciona por sua vez, a conquista de vantagens competitivas frente às demais organizações. O modelo de Cadeia de Valor originalmente proposto por Porter (1989), é uma estrutura composta por dois conjuntos de atividades, que integradas possibilitam à organização potencializar sua margem. A complexidade das atividades operacionais de uma Instituição de Ensino, intensiva em mão de obra qualificada, permite refletir a cerca de modelos e estruturas capazes de auxiliarem no oferecimento de ensino qualificado. Para o desenvolvimento desse estudo, o método utilizado foi a abordagem qualitativa e exploratória, utilizando procedimentos técnicos do tipo fontes secundárias e levantamentos bibliográficos sobre o assunto. Como resultado deste estudo é apresentado um modelo de cadeia de valor para uma Instituição de Ensino Superior.
Ensino superior à ordem do capital internacional
Authors: Borges Vanessa Maria de Oliveira , Aquino Edson Tomaz de
Published: April 2013

A formatação e o reordenamento de poder do mundo atual não excluem a organização universitária. O entorno político, econômico, social e cultural exercem um enorme impacto na educação superior, que não pode e nem deve ficar de fora das mudanças que se apresentam na sociedade. É por isso que a cooperação internacional vem se implantando como um processo de grande relevância no mundo universitário, sendo ponto de discussão acadêmica em diversos países. Por outro lado, a redução da interferência do Estado na economia e a internacionalização dos serviços, permite que o ensino superior seja tratado como uma commodity no comércio internacional. Nesse contexto, o presente estudo visa analisar os elementos políticos centrais do debate sobre a incorporação, cada vez maior, das demandas do capital internacional na educacional brasileira. Para viabilizar o alcance dos objetivos dessa pesquisa – dentre os quais, analisar a ação ofensiva do capital internacional no ensino superior brasileiro – será utilizado como referencial teórico, o Paradigma Globalista das Relações Internacionais, sob a perspectiva da Teoria da Dependência e as relações centro-periferia. Os procedimentos metodológicos utilizados para a realização deste artigo permitem qualificá-lo como resumo de assunto (quanto à sua natureza) e como explicativa (quanto aos seus objetivos). Os procedimentos de coleta de dados voltaram-se para a obtenção de dados secundários, já publicados em livros, artigos, periódicos, sites etc. Deste modo, este trabalho qualifica-se como bibliográfico, no que se refere ao seu objeto, e qualitativo no que diz respeito à sua abordagem, realizando, assim, uma análise interpretativa dos dados obtidos e dos fenômenos observados.
Evolution of Antarctic ozone in September–December predicted by CCMVal-2 model simulations for the 21st century
Authors: Siddaway J. M. , Petelina S. V. , Karoly D. J. , Klekociuk A. R. , Dargaville R. J.
Published: April 2013

Abstract. Chemistry-Climate Model Validation phase 2 (CCMVal-2) model simulations are used to analyze Antarctic ozone increases in 2000–2100 during local spring and early summer, both vertically integrated and at several pressure levels in the lower stratosphere. Multi-model median trends of monthly zonal mean total ozone column (TOC), ozone volume mixing ratio (VMR), wind speed and temperature poleward of 60° S are investigated. Median values are used to account for large variability in models, and the associated uncertainty is calculated using a bootstrapping technique. According to the trend derived from the twelve CCMVal-2 models selected, Antarctic TOC will not return to a 1965 baseline, an average of 1960–1969 values, by the end of the 21st century in September–November, but will return in ~2080 in December. The speed of December ozone depletion before 2000 was slower compared to spring months, and thus the decadal rate of December TOC increase after 2000 is also slower. Projected trends in December ozone VMR at 20–100 hPa show a much slower rate of ozone recovery, particularly at 50–70 hPa, than for spring months. Trends in temperature and winds at 20–150 hPa are also analyzed in order to attribute the projected slow increase of December ozone and to investigate future changes in the Antarctic atmosphere in general, including some aspects of the polar vortex breakup.
Four-dimensional distribution of the 2010 Eyjafjallajökull volcanic cloud over Europe observed by EARLINET
Authors: Pappalardo G. , Mona L. , D'Amico G. , Wandinger U. , Adam M. , Amodeo A. , Ansmann A. , Apituley A. , Alados Arboledas L. , Balis D. , Boselli A. , Bravo-Aranda J. A. , Chaikovsky A. , Comeron A. , Cuesta J. , De Tomasi F. , Freudenthaler V. , Gausa M. , Giannakaki E. , Giehl H. , Giunta A. , Grigorov I. , Groß S. , Haeffelin M. , Hiebsch A. , Iarlori M. , Lange D. , Linné H. , Madonna F. , Mattis I. , Mamouri R.-E. , McAuliffe M. A. P. , Mitev V. , Molero F. , Navas-Guzman F. , Nicolae D. , Papayannis A. , Perrone M. R. , Pietras C. , Pietruczuk A. , Pisani G. , Preißler J. , Pujadas M. , Rizi V. , Ruth A. A. , Schmidt J. , Schnell F. , Seifert P. , Serikov I. , Sicard M. , Simeonov V. , Spinelli N. , Stebel K. , Tesche M. , Trickl T. , Wang X. , Wagner F. , Wiegner M. , Wilson K. M.
Published: April 2013

Abstract. The eruption of the Icelandic volcano Eyjafjallajökull in April–May 2010 represents a "natural experiment" to study the impact of volcanic emissions on a continental scale. For the first time, quantitative data about the presence, altitude, and layering of the volcanic cloud, in conjunction with optical information, are available for most parts of Europe derived from the observations by the European Aerosol Research Lidar NETwork (EARLINET). Based on multi-wavelength Raman lidar systems, EARLINET is the only instrument worldwide that is able to provide dense time series of high-quality optical data to be used for aerosol typing and for the retrieval of particle microphysical properties as a function of altitude. In this work we show the four-dimensional (4-D) distribution of the Eyjafjallajökull volcanic cloud in the troposphere over Europe as observed by EARLINET during the entire volcanic event (15 April–26 May 2010). All optical properties directly measured (backscatter, extinction, and particle linear depolarization ratio) are stored in the EARLINET database available at http://www.earlinet.org. A specific relational database providing the volcanic mask over Europe, realized ad hoc for this specific event, has been developed and is available on request at http://www.earlinet.org. During the first days after the eruption, volcanic particles were detected over Central Europe within a wide range of altitudes, from the upper troposphere down to the local planetary boundary layer (PBL). After 19 April 2010, volcanic particles were detected over southern and south-eastern Europe. During the first half of May (5–15 May), material emitted by the Eyjafjallajökull volcano was detected over Spain and Portugal and then over the Mediterranean and the Balkans. The last observations of the event were recorded until 25 May in Central Europe and in the Eastern Mediterranean area. The 4-D distribution of volcanic aerosol layering and optical properties on European scale reported here provides an unprecedented data set for evaluating satellite data and aerosol dispersion models for this kind of volcanic events.
Stratospheric SO2 and sulphate aerosol, model simulations and satellite observations
Authors: Brühl C. , Lelieveld J. , Höpfner M. , Tost H.
Published: April 2013

Abstract. A multiyear study with the atmospheric chemistry general circulation model EMAC with the aerosol module GMXe at high altitude resolution demonstrates that the sulfur gases COS and SO2, the latter from low-latitude volcanic eruptions, predominantly control the formation of stratospheric aerosol. The model consistently uses the same parameters in the troposphere and stratosphere for 7 aerosol modes applied. Lower boundary conditions for COS and other long-lived trace gases are taken from measurement networks, while estimates of volcanic SO2 emissions are based on satellite observations. We show comparisons with satellite data for aerosol extinction (e.g. SAGE) and SO2 in the middle atmosphere (MIPAS on ENVISAT). This corroborates the interannual variability induced by the Quasi-Biennial Oscillation, which is internally generated by the model. The model also realistically simulates the radiative effects of stratospheric and tropospheric aerosol including the effects on the model dynamics. The medium strength volcanic eruptions of 2005 and 2006 exerted a nonnegligible radiative forcing of up to −0.6 W m−2 in the tropics, while the large Pinatubo eruption caused a maximum though short term tropical forcing of about −10 W m−2. The study also shows that observed upper stratospheric SO2 can be simulated accurately only when a sulphur sink on meteoritic dust is included and the photolysis of gaseous H2SO4 in the near infrared is higher than assumed previously.
Assessment of COSMIC radio occultation retrieval product using global radiosonde data
Authors: Wang B.-R. , Liu X.-Y. , Wang J.-K.
Published: April 2013

Abstract. The radio occultation retrieval product of the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Radio Occultation sounding system was verified using the global radiosonde data from 2007 to 2010. Samples of 4 yr were used to collect quantities of data using much stricter matching criteria than previous studies to obtain more accurate results. The horizontal distance between the radiosonde station and the occultation event is within 100 km, and the time window is 1 h. The comparison was performed from 925 hPa to 10 hPa. The results indicated that the COSMIC's temperature data agreed well with the radiosonde data. The global mean temperature bias was −0.09 K, with a standard deviation (SD) of 1.72 K. According to the data filtration used in this paper, the mean specific humidity bias of 925–200 hPa is −0.012 g kg−1, with a SD of 0.666 g kg−1, and the mean relative error of water vapor pressure is about 33.3%, with a SD of 107.5%. The COSMIC quality control process failed to detect some of the abnormal extremely small humidity data which occurred frequently in subtropical zone. Despite the large relative error of water vapor pressure, the relative error of refractivity is small. This paper also provides a comparison of eight radiosonde types with COSMIC product. Because the retrieval product is affected by the background error which differed between different regions, the COSMIC retrieval product could be used as a benchmark if the precision requirement is not strict.
Uncertainty characterization of AOD for the AATSR dual and single view retrieval algorithms
Authors: Kolmonen P. , Sundström A.-M. , Sogacheva L. , Rodriguez E. , Virtanen T. , de Leeuw G.
Published: April 2013

Abstract. The uncertainty associated with satellite-retrieved aerosol properties is needed when these data are used to constrain chemical transport or climate models by using data assimilation. Global uncertainty as provided by comparison with independent ground-based observations is usually not adequate for that purpose. Rather the per-pixel uncertainty is needed. In this work we describe how these are determined in the AATSR dual and single view aerosol retrieval algorithms (ADV and ASV) which are used to retrieve aerosol optical properties from reflectance measured at the top of the atmosphere. AATSR is the Aerosol Along-Track Scanning Radiometer which flies on the European Space Agency Environmental Satellite ENVISAT. In addition, issues related to multi-year retrievals are described and discussed. The aerosol optical depth (AOD) retrieved for the year 2008 is validated versus ground-based AERONET sun photometer measurements with good agreement (r = 0.85). The comparison of the AOD uncertainties with those provided by AERONET shows that they behave well in a statistical sense. Other considerations regarding global multi-year aerosol retrievals are presented and discussed.
Technical Note: Pitfalls with the use of enhancement ratios or normalized excess mixing ratios measured in plumes to characterize pollution sources and aging
Authors: Yokelson R. J. , Andreae M. O. , Akagi S. K.
Published: April 2013

Abstract. Normalized excess mixing ratios (NEMRs), also known as enhancement ratios, are a common way to characterize plumes of pollution in atmospheric research. As single-source pollutant plumes disperse in the atmosphere they are diluted by mixing with the adjacent background air. Changes in the composition of this background air can cause large changes to the NEMR that is subsequently measured by remote-sensing, airborne, or ground-based instruments. This scenario is common when boundary layer plumes enter the free troposphere and could also impact long range transport or plumes near the top of the troposphere. We provide a context for these issues and an example showing that neglect of this effect could lead to serious errors in data interpretation.
Land use change effects on runoff generation in a humid tropical montane cloud forest region
Authors: Muñoz-Villers L. E. , McDonnell J. J.
Published: April 2013

Abstract. While tropical montane cloud forests (TMCF) provide critical hydrological services to downstream regions throughout much of the humid tropics, catchment hydrology and impacts associated with forest conversion in these ecosystems remain poorly understood. Here, we compare the annual, seasonal and event-scale streamflow patterns and runoff generation processes of three neighbouring headwater catchments in central Veracruz (eastern Mexico) with similar pedological and geological characteristics, but different land cover: old-growth TMCF (MAT), 20 yr-old naturally regenerating TMCF (SEC) and a heavily grazed pasture (PAS). We used a 2 yr record of high resolution rainfall and stream flow data (2008–2010) in combination with stable isotope and chemical tracer data collected for a series of storms during a 6-week period of increasing antecedent wetness (wetting-up cycle). Our results showed that annual and seasonal streamflow patterns of the MAT and SEC were similar. In contrast, the PAS showed a 10% higher mean annual streamflow, most likely because of a lower rainfall interception. During the wetting-up cycle, storm runoff ratios increased at all three catchments (from 11 to 54% for the MAT, 7 to 52% for the SEC and 3 to 59% for the PAS). With the increasing antecedent wetness, hydrograph separation analysis showed progressive increases of pre-event water contributions to total stormflow (from 35 to 99% in the MAT, 26 to 92% in the SEC and 64 to 97% in the PAS). At all three sites, rainfall-runoff responses were dominated by subsurface flow generation processes for the majority of storms. However, for the largest and most intense storm (typically occurring once every 2 yr), sampled under wet antecedent conditions, the event water contribution in the PAS (34% on average) was much higher than in the forests (5% on average), indicating that rainfall infiltration capacity of the PAS was exceeded. This result suggests that despite the high permeability of the volcanic soils and underlying substrate in this TMCF environment, the conversion of forest to pasture may lead to important changes in runoff generation processes during large and high intensity storms. On the other hand, our results also showed that 20 yr of natural regeneration may be enough to largely restore the original hydrological conditions of this TMCF.
The influence of conceptual model structure on model performance: a comparative study for 237 French catchments
Authors: van Esse W. R. , Perrin C. , Booij M. J. , Augustijn D. C. M. , Fenicia F. , Lobligeois F.
Published: April 2013

Abstract. In hydrological studies models with a fixed structure are commonly used. For various reasons, these models do not always perform well. As an alternative, a flexible modelling approach could be followed, where the identification of the model structure is part of the model set-up procedure. In this study, the performance of twelve different conceptual model structures from the SUPERFLEX framework with varying complexity and the fixed model structure of GR4H were compared on a large set of 237 French catchments. The results showed that in general the flexible approach performs better than the fixed approach. However, the flexible approach has a higher chance of inconsistent results when implemented on two different periods. The same holds for more complex model structures. When for practical reasons a fixed model structure is preferred, this study shows that models with parallel reservoirs and a power function to describe the reservoir outflow perform best. In general, conceptual hydrological models perform better on large or wet catchments than on small or dry catchments. The model structures performed poorly when there was a climatic difference between the calibration and validation period, for catchments with flashy flows or disturbances in low flow measurements.
Flow resistance of vegetated oblique weir-like obstacles during high water stages
Authors: Ali S. , Uijttewaal W. S. J.
Published: April 2013

Abstract. At high water stages obstacles in the flood plains of a river contribute to the flow resistance and hamper the conveyance capacity. In particular the elevated vegetated parts are expected to play an important role. The objective of this research work is to determine the form drag due to vegetated oblique weir-like obstacles. The experiments have been performed to measure the energy head losses for a range of subcritical flow conditions, varying discharges and downstream water levels. The energy head loss caused by the submerged vegetated weir-like obstacle has been modeled using an expansion loss form drag model that has been derived from one dimensional momentum conservation equation and accounts for the energy loss associated with a deceleration of the flow downstream of a sudden expansion. The results have been compared with the experimental data and showed an overall good agreement.
Tidally-induced velocity variations of the Beardmore Glacier, Antarctica, and their representation in satellite measurements of ice velocity
Authors: Marsh O. J. , Rack W. , Floricioiu D. , Golledge N. R. , Lawson W.
Published: April 2013

Abstract. Ocean tides close to the grounding line of outlet glaciers around Antarctica have been shown to directly influence ice velocity, in both linear and non-linear patterns. These fluctuations can be significant and have the potential to affect satellite measurements of ice discharge which assume displacement between satellite passes to be consistent and representative of annual means. Satellite observations of horizontal velocity variation in the grounding zone are also contaminated by vertical tidal effects, shown here to be present in speckle tracking measurements. Eight TerraSAR-X scenes from the grounding zone of the Beardmore Glacier are analysed in conjunction with GPS measurements to determine short-term and decadal trends in ice velocity. Diurnal tides produce horizontal velocity fluctuations of >50% on the ice shelf, recorded in the GPS data 4 km downstream of the grounding line. This decreases rapidly to <5% only 15 km upstream of the grounding line. Daily fluctuations are smoothed to <1% in the 11 day repeat pass TerraSAR-X imagery but fortnightly variations over this period are still visible and show that satellite-velocity measurements can be affected by tides over longer periods. The measured tidal displacement observed in radar look direction over floating ice also allows a~new method of grounding line identification to be demonstrated, using differential speckle tracking where phase coherence is too poor for SAR interferometry.
Western Faculty Profile: Dr. Moshmi Bhattacharya
Authors: Yung Jason C
Published: April 2013

Dr. Moshmi Bhattacharya is an Associate Professor in the Departments of Physiology and Pharmacology, and Oncology at the Schulich School of Medicine and Dentistry, University of Western Ontario. Her research is directed on understanding the molecular mechanisms through which receptors expressed in breast cancer cells regulate cell migration, invasion, processes that lead to metastatic spread of breast cancer.
She currently teaches a 4th year Pharmacology Course "Mechanisms of Cancer Chemotherapy". She also participated heavily in undergraduate training, and also trains high school students. WURJ member, Jason Yung, had the pleasant opportunity to interview her to learn more about her as a person, researcher, and professor.
Quantifying the Characteristics of the Acetabulum and Proximal Femur using a Semi-automated Hip Morphology Software Programme (SHIPS)
Authors: Thiagarajah Shankar , MacInnes Scott , Yang Lang , Doherty Michael , Wilkinson Jeremy M.
Published: April 2013

Background

Hip-joint shape is an important factor that affects an individual's risk of developing osteoarthritis (OA). However, validated tools to quantify these morphological characteristics on clinical plain radiographs are few. We developed a Matlab-based Semi-automated HIP Software programme (SHIPS) that measures 10 morphologic characteristics of the hip that are risk factors for OA using a plain digitised antero-posterior pelvic radiograph. In this study we validated the accuracy and repeatability of this freeware-tool.

Methods

Software accuracy was assessed using a test pelvic radiograph, and by repeated measurements of an AP-pelvic radiograph digitally recreated from pelvis computed-tomography images reformatted to create images rotated in 2-dimensions (2.5° increments, range −15° to +15°). Intra- and inter-observer repeatability was assessed using pelvic radiographs from 30 subjects analysed twice using the software by two readers, and expressed as coefficient of variation (CV). Clinical-repeatability was assessed by measuring sequential pelvic radiographs taken on the same day after re-positioning in 23 subjects.

Results

Software accuracy was within 0.1% for linear-ratios and 0.4° for angular-measurements. Changes in pelvic inclination and rotation of ±15° resulted in <14% change in linear-measurement ratios and <7° change in angular-measurements. The intra-observer CV was between 0.3 to 4.1%, and inter-observer CV 0.7 to 9.7% with the exception of horizontal-toit-externa (HTE, 14.6 and 24.2% respectively). Short-term clinical-repeatability varied from 0.4 to 6.1%, with the exception of HTE (37.4%).

Conclusion

The software showed good accuracy and repeatability for measurement of most hip-joint morphologic risk factors for OA apart from HTE. This tool has particular value in studying large or retrospective datasets where cross-sectional imaging is not feasible or available.
In Search of America: Sidney Robertson Cowell in Ireland in 1955–1956
Authors: Ní Chonghaile Deirdre
Published: April 2013

This article discusses the American folk music collector and ethnomusicologist Sidney Robertson Cowell (1903-1995). It considers the work she conducted in Ireland in 1955 and 1956 in light of her twenty-one-year career from 1936 to 1957, during which she collected in America, Canada, Iran, Bangladesh, Thailand, and Malaysia. It investigates how her interest in the question of the identity of American music influenced her work.