Solución a un problema estático en un área con topografía abrupta usando una velocidad de reemplazamiento variable

Directory of Open Access Journals (Sweden)

Castillo López Luis Antonio

2002-08-01

calculate with variable velocity is proposed.

margin: 0cm 0cm 0pt; mso-layout-grid-align: none;">This method have been development in the processing data in areas with irregular surface. For instance, Piedemonte Llanero. The software calculation is ProMAX, algorithm Gauss-Sediel.

margin: 0cm 0cm 0pt; mso-layout-grid-align: none;">Teniendo en cuenta que para poder obtener una buena imagen del subsuelo, es necesario que las soluciones estáticas sean las mas acertadas posibles en la etapa inicial del procesamiento, y no gastar tiempo en ensayos con procesos mas sofisticados, sin tener resuelto el problema estático, se propone implantar un método de procesamiento usando un modelo de velocidad de reemplazamiento variable en el cálculo de la solución estática. Se pretende explicar que el valor de la velocidad de reemplazamiento influye notoriamente en la imagen de la estructura, la cual puede verse deformada en gran magnitud. Tambien puede ser cuestionado cómo ha sido asignado este valor de manera constante en los proyectos, dando más importancia al amarre con áreas cercanas que a la solución misma del problema estático.

margin: 0cm 0cm 0pt; mso-layout-grid-align: none;">Se mostrara un estudio en que se emplea una serie de datos reales procesados a partir de un modelo de velocidad de reemplazamiento variable y otra con un modelo de velocidad constante, las que -al ser comparadas y analizadas- dan como resultado grandes contrastes en las imageries obtenidas.

margin: 0cm 0cm 0pt; mso-layout-grid-align: none;">Este método se ha ido desarrollando durante el procesamiento de

Effect of Margin Designs on the Marginal Adaptation of Zirconia Copings.

Science.gov (United States)

Habib, Syed Rashid; Al Ajmi, Mohammed Ginan; Al Dhafyan, Mohammed; Jomah, Abdulrehman; Abualsaud, Haytham; Almashali, Mazen

2017-09-01

The aim of this in vitro study was to investigate the effect of Shoulder versus Chamfer margin design on the marginal adaptation of zirconia (Zr) copings. 40 extracted molar teeth were mounted in resin and prepared for zirconia crowns with two margin preparation designs (20=Shoulder and 20=Chamfer). The copings were manufactured by Cercon® (DeguDent GmbH, Germany) using the CAD/CAM system for each tooth. They were tried on each tooth, cemented, thermocycled, re-embedded in resin and were subsequently cross sectioned centrally into two equal mesial and distal halves. They were examined under electron microscope at 200 X magnification and the measurements were recorded at 5 predetermined points in micrometers (µm). The o verall mean marginal gap for the two groups was found to be 206.98+42.78µm with Shoulder margin design (Marginal Gap=199.50+40.72µm) having better adaptation compared to Chamfer (Marginal Gap=214.46+44.85µm). The independent-samples t-test showed a statistically non-significant difference (p=.113) between the means of marginal gap for Shoulder and Chamfer margin designs and the measurements were recorded at 5 predetermined points for the two groups. The Chamfer margin design appeared to offer the same adaptation results as the Shoulder margin design.

O doador marginal: experiência de um centro de transplante de fígado The marginal donor: a single-center experience in orthotopic liver transplantation

Directory of Open Access Journals (Sweden)

Olival Cirilo Lucena da Fonseca-Neto

2008-03-01

Full Text Available RACIONAL: Desde que o uso de enxertos marginais é solução aceita para escassez de órgãos para transplante, ele tornou-se muito comum em todo mundo e a literatura vem mostrando efetividade desses enxertos no transplante de fígado. OBJETIVO: Apresentar a experiência do Serviço de Transplante Hepático do Hospital Universitário Oswaldo Cruz, em transplante de fígado com o uso de doadores marginais. MÉTODOS: Estudo retrospectivo em 137 transplantes ortotópicos de fígado, usando enxertos marginais entre 1999 e 2006, com acompanhamento mínimo de 180 dias. Os receptores foram classificados de acordo com a função inicial do enxerto no pós-operatório como normal (FN e disfunção primária (DP. RESULTADOS: Não foi observada diferença estatisticamente significante entre os grupos FN e DP com os seguintes parâmetros dos doadores: idade, sódio sérico, tempo de protrombina, esteatose hepática, transaminases sérica, pressão sanguínea, drogas vasoativas, índice de massa corpórea, parada cardíaca antes da doação de órgão, doador em assistolia e tempo de isquemia quente. Análise da curva de sobrevida (Kaplan-Meier de pacientes e de enxertos de fígado de pacientes que receberam fígado de doadores ideais versus doadores marginais não mostrou diferença com significância estatística. CONCLUSÃO: Pode ser recomendado o uso de enxertos marginais para transplantes hepáticos, inclusive os provenientes de doadores com o coração parado.BACKGROUND: Since marginal grafts are a solution to deal with the shortage of organ donors, its use became more common worldwide, and the literature had shown its effectiveness in the liver transplantation (LT outcomes. AIM: To present a single center experience, at the Liver Transplantation Unit of Oswaldo Cruz University Hospital, with orthotopic LT using marginal organ donors. METHODS: Retrospectivety review of 137 orthotopic LT using marginal grafts between 1999 and 2006, with a minimum 180

Matthew and marginality

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Denis C. Duling

1995-12-01

Full Text Available This article explores marginality theory as it was first proposed in  the social sciences, that is related to persons caught between two competing cultures (Park; Stonequist, and, then, as it was developed in sociology as related to the poor (Germani and in anthropology as it was related to involuntary marginality and voluntary marginality (Victor Turner. It then examines a (normative scheme' in antiquity that creates involuntary marginality at the macrosocial level, namely, Lenski's social stratification model in an agrarian society, and indicates how Matthean language might fit with a sample inventory  of socioreligious roles. Next, it examines some (normative schemes' in  antiquity for voluntary margi-nality at the microsocial level, namely, groups, and examines how the Matthean gospel would fit based on indications of factions and leaders. The article ,shows that the author of the Gospel of Matthew has an ideology of (voluntary marginality', but his gospel includes some hope for (involuntary  marginals' in  the  real world, though it is somewhat tempered. It also suggests that the writer of the Gospel is a (marginal man', especially in the sense defined by the early theorists (Park; Stone-quist.

Construcción de Distribuciones Multivariadas con Marginales Dependientes Usando Cópulas en R

OpenAIRE

Jaramillo-Elorza, M. C; Lozano, J. A

2014-01-01

Las cópulas se han convertido en una herramienta popular para la construcción de modelos multivariados en campos donde la dependencia multivariada es de gran interés. El propósito de este trabajo es presentar las cópulas tanto en su concepto teórico, como en su implementación en el software estadístico R y profundizar en la construcción de distribuciones multivariadas con marginales dependientes, usando la clase mvdc del paquete copula, la cual permite utilizar varias y diferentes marginales ...

Marginal and happy? The need for uniqueness predicts the adjustment of marginal immigrants.

Science.gov (United States)

Debrosse, Régine; de la Sablonnière, Roxane; Rossignac-Milon, Maya

2015-12-01

Marginalization is often presented as the strategy associated with the worst adjustment for immigrants. This study identifies a critical variable that buffers marginal immigrants from the negative effects of marginalization on adjustment: The need for uniqueness. In three studies, we surveyed immigrants recruited on university campuses (n = 119, n = 116) and in the field (n = 61). Among marginal immigrants, a higher need for uniqueness predicted higher self-esteem (Study 1), affect (Study 2), and life satisfaction (Study 3), and marginally higher happiness (Study 2) and self-esteem (Study 3). No relationship between the need for uniqueness and adjustment was found among non-marginal immigrants. The adaptive value of the need for uniqueness for marginal immigrants is discussed. © 2015 The British Psychological Society.

Guía metodológica para obtener patrones de accidentabilidad laboral usando Data Mining

OpenAIRE

Cevallos Chacón, Alvaro

2013-01-01

El objetivo de esta investigación es desarrollar y proponer una metodología clara y objetiva que permita a las empresas de cualquier industria, investigar sobre patrones de accidentabilidad laboral usando la minería de datos como herramienta de análisis. Para tal efecto se combina los conceptos de seguridad industrial relacionados con la investigación de accidentes y toma como marco principal, la normatividad nacional vigente en materia de seguridad y salud en el trabajo. Estos conceptos son ...

SISTEMA DE MODELAGEM DE FIGURAS TRIDIMENSIONAIS USANDO RECONHECIMENTO DE VOZ

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Kauan Cristiano De Souza

2017-01-01

Full Text Available Atualmente o mercado de Sistemas de Desenho auxiliado por Computador (CAD, sofre extrema carência de processos automatizados de reconhecimento de fala. O surgimento de tecnologias de automação facilita no desenvolvimento de aplicações capazes de auxiliar nestes processos. Baseando-se nestas afirmações construiu-se um modelo utilizando tecnologias capazes de transformar fala em sinais digitais, sendo possível a interpretação por sofisticados computadores. Observando ausência de tais ferramentas, o presente trabalho busca uma proposta capaz de acrescentar mecanismos os quais possibilitem a criação de modelos tridimensionais usando tecnologias como servidores HTTP, dispositivos moveis, linguagens de programação Java e PHP, Computação Gráfica e linguagem de interpretação por blocos. Os resultados obtidos na confecção do presente trabalho corroboram com as necessidades atuais representadas na sociedade propondo sustentabilidade, acessibilidade, portabilidade e facilidade de comunicação.

"We call ourselves marginalized"

DEFF Research Database (Denmark)

Jørgensen, Nanna Jordt

2014-01-01

of the people we refer to as marginalized. In this paper, I discuss how young secondary school graduates from a pastoralist community in Kenya use and negotiate indigeneity, marginal identity, and experiences of marginalization in social navigations aimed at broadening their current and future opportunities. I...

Marginal Matter

Science.gov (United States)

van Hecke, Martin

2013-03-01

All around us, things are falling apart. The foam on our cappuccinos appears solid, but gentle stirring irreversibly changes its shape. Skin, a biological fiber network, is firm when you pinch it, but soft under light touch. Sand mimics a solid when we walk on the beach but a liquid when we pour it out of our shoes. Crucially, a marginal point separates the rigid or jammed state from the mechanical vacuum (freely flowing) state - at their marginal points, soft materials are neither solid nor liquid. Here I will show how the marginal point gives birth to a third sector of soft matter physics: intrinsically nonlinear mechanics. I will illustrate this with shock waves in weakly compressed granular media, the nonlinear rheology of foams, and the nonlinear mechanics of weakly connected elastic networks.

Marginalization of the Youth

DEFF Research Database (Denmark)

Jensen, Niels Rosendal

2009-01-01

The article is based on a key note speach in Bielefeld on the subject "welfare state and marginalized youth", focusing upon the high ambition of expanding schooling in Denmark from 9 to 12 years. The unintended effect may be a new kind of marginalization.......The article is based on a key note speach in Bielefeld on the subject "welfare state and marginalized youth", focusing upon the high ambition of expanding schooling in Denmark from 9 to 12 years. The unintended effect may be a new kind of marginalization....

Convexity and Marginal Vectors

NARCIS (Netherlands)

van Velzen, S.; Hamers, H.J.M.; Norde, H.W.

2002-01-01

In this paper we construct sets of marginal vectors of a TU game with the property that if the marginal vectors from these sets are core elements, then the game is convex.This approach leads to new upperbounds on the number of marginal vectors needed to characterize convexity.An other result is that

Contributions to knowledge of the continental margin of Uruguay. Uruguayan continental margin: Physiographic and seismic analysis

International Nuclear Information System (INIS)

Preciozzi, F

2014-01-01

This work is about the kind of continental margins such as a )Atlantic type passive margins which can be hard or soft b) An active or Pacific margins that because of the very frequent earthquakes develop a morphology dominated by tectonic processes. The Uruguayan continental margin belongs to a soft Atlantic margin

Fixing soft margins

NARCIS (Netherlands)

P. Kofman (Paul); A. Vaal, de (Albert); C.G. de Vries (Casper)

1993-01-01

textabstractNon-parametric tolerance limits are employed to calculate soft margins such as advocated in Williamson's target zone proposal. In particular, the tradeoff between softness and zone width is quantified. This may be helpful in choosing appropriate margins. Furthermore, it offers

SOCIAL MARGINALIZATION AND HEALTH

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Marjana Bogdanović

2007-04-01

Full Text Available The 20th century was characterized by special improvement in health. The aim of WHO’s policy EQUITY IN HEALTH is to enable equal accessibility and equal high quality of health care for all citizens. More or less some social groups have stayed out of many social systems even out of health care system in the condition of social marginalization. Phenomenon of social marginalization is characterized by dynamics. Marginalized persons have lack of control over their life and available resources. Social marginalization stands for a stroke on health and makes the health status worse. Low socio-economic level dramatically influences people’s health status, therefore, poverty and illness work together. Characteristic marginalized groups are: Roma people, people with AIDS, prisoners, persons with development disorders, persons with mental health disorders, refugees, homosexual people, delinquents, prostitutes, drug consumers, homeless…There is a mutual responsibility of community and marginalized individuals in trying to resolve the problem. Health and other problems could be solved only by multisector approach to well-designed programs.

Pickering seismic safety margin

International Nuclear Information System (INIS)

Ghobarah, A.; Heidebrecht, A.C.; Tso, W.K.

1992-06-01

A study was conducted to recommend a methodology for the seismic safety margin review of existing Canadian CANDU nuclear generating stations such as Pickering A. The purpose of the seismic safety margin review is to determine whether the nuclear plant has sufficient seismic safety margin over its design basis to assure plant safety. In this review process, it is possible to identify the weak links which might limit the seismic performance of critical structures, systems and components. The proposed methodology is a modification the EPRI (Electric Power Research Institute) approach. The methodology includes: the characterization of the site margin earthquake, the definition of the performance criteria for the elements of a success path, and the determination of the seismic withstand capacity. It is proposed that the margin earthquake be established on the basis of using historical records and the regional seismo-tectonic and site specific evaluations. The ability of the components and systems to withstand the margin earthquake is determined by database comparisons, inspection, analysis or testing. An implementation plan for the application of the methodology to the Pickering A NGS is prepared

Indian Ocean margins

Digital Repository Service at National Institute of Oceanography (India)

Naqvi, S.W.A

in the latter two areas. Some of these fluxes are expected to be substantial in the case of Indonesian continental margins and probably also across the eastern coasts of Africa not covered in this chapter. However, a dearth of information makes these margins...

Síntesis de oxitocina en fase sólida usando derivados de terbutoxicarbonilo y fluorenilmetoxicarbonilo

OpenAIRE

Calvo, Julio C; Barrera, Nubia F.; García, Josué A.; Guzman, Fanny; Espejo, Fabiola; Patarroyo, Manuel E.

2010-01-01

La oxitocina, péptido cíclico cuya secuencia es CYIQNCPLG, fué el primer péptido de importancia biológica que pudo ser sintetizado. En este trabajo se compara la síntesis de la oxitocina usando resina p metilbenzhidrilamina (MBHA) para la síntesis por estrategia t-Boc y resina Rink p-metilbenzhidrilamina (Rink MBHA) para la síntesis por estrategia Fmoc, con altos rendimientos. El péptido crudo se ciclizó en una disolución acuosa de dimetilsulfóxido al 10%. La caracterización se llevó a cabo p...

Marginal kidney donor

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Ganesh Gopalakrishnan

2007-01-01

Full Text Available Renal transplantation is the treatment of choice for a medically eligible patient with end stage renal disease. The number of renal transplants has increased rapidly over the last two decades. However, the demand for organs has increased even more. This disparity between the availability of organs and waitlisted patients for transplants has forced many transplant centers across the world to use marginal kidneys and donors. We performed a Medline search to establish the current status of marginal kidney donors in the world. Transplant programs using marginal deceased renal grafts is well established. The focus is now on efforts to improve their results. Utilization of non-heart-beating donors is still in a plateau phase and comprises a minor percentage of deceased donations. The main concern is primary non-function of the renal graft apart from legal and ethical issues. Transplants with living donors outnumbered cadaveric transplants at many centers in the last decade. There has been an increased use of marginal living kidney donors with some acceptable medical risks. Our primary concern is the safety of the living donor. There is not enough scientific data available to quantify the risks involved for such donation. The definition of marginal living donor is still not clear and there are no uniform recommendations. The decision must be tailored to each donor who in turn should be actively involved at all levels of the decision-making process. In the current circumstances, our responsibility is very crucial in making decisions for either accepting or rejecting a marginal living donor.

On marginal regeneration

NARCIS (Netherlands)

Stein, H.N.

1991-01-01

On applying the marginal regeneration concept to the drainage of free liquid films, problems are encountered: the films do not show a "neck" of minimum thickness at the film/border transition; and the causes of the direction dependence of the marginal regeneration are unclear. Both problems can be

Indigenous women's voices: marginalization and health.

Science.gov (United States)

Dodgson, Joan E; Struthers, Roxanne

2005-10-01

Marginalization may affect health care delivery. Ways in which indigenous women experienced marginalization were examined. Data from 57 indigenous women (18 to 65 years) were analyzed for themes. Three themes emerged: historical trauma as lived marginalization, biculturalism experienced as marginalization, and interacting within a complex health care system. Experienced marginalization reflected participants' unique perspective and were congruent with previous research. It is necessary for health care providers to assess the detrimental impact of marginalization on the health status of individuals and/or communities.

Refining margins and prospects

International Nuclear Information System (INIS)

Baudouin, C.; Favennec, J.P.

1997-01-01

Refining margins throughout the world have remained low in 1996. In Europe, in spite of an improvement, particularly during the last few weeks, they are still not high enough to finance new investments. Although the demand for petroleum products is increasing, experts are still sceptical about any rapid recovery due to prevailing overcapacity and to continuing capacity growth. After a historical review of margins and an analysis of margins by regions, we analyse refining over-capacities in Europe and the unbalances between production and demand. Then we discuss the current situation concerning barriers to the rationalization, agreements between oil companies, and the consequences on the future of refining capacities and margins. (author)

Safety margins in deterministic safety analysis

International Nuclear Information System (INIS)

Viktorov, A.

2011-01-01

The concept of safety margins has acquired certain prominence in the attempts to demonstrate quantitatively the level of the nuclear power plant safety by means of deterministic analysis, especially when considering impacts from plant ageing and discovery issues. A number of international or industry publications exist that discuss various applications and interpretations of safety margins. The objective of this presentation is to bring together and examine in some detail, from the regulatory point of view, the safety margins that relate to deterministic safety analysis. In this paper, definitions of various safety margins are presented and discussed along with the regulatory expectations for them. Interrelationships of analysis input and output parameters with corresponding limits are explored. It is shown that the overall safety margin is composed of several components each having different origins and potential uses; in particular, margins associated with analysis output parameters are contrasted with margins linked to the analysis input. While these are separate, it is possible to influence output margins through the analysis input, and analysis method. Preserving safety margins is tantamount to maintaining safety. At the same time, efficiency of operation requires optimization of safety margins taking into account various technical and regulatory considerations. For this, basic definitions and rules for safety margins must be first established. (author)

Marginal Models for Categorial Data

NARCIS (Netherlands)

Bergsma, W.P.; Rudas, T.

2002-01-01

Statistical models defined by imposing restrictions on marginal distributions of contingency tables have received considerable attention recently. This paper introduces a general definition of marginal log-linear parameters and describes conditions for a marginal log-linear parameter to be a smooth

Digital Margins : How spatially and socially marginalized communities deal with digital exclusion

NARCIS (Netherlands)

Salemink, Koen

2016-01-01

The increasing importance of the Internet as a means of communication has transformed economies and societies. For spatially and socially marginalized communities, this transformation has resulted in digital exclusion and further marginalization. This book presents a study of two kinds of

Informing practice regarding marginalization: the application of the Koci Marginality Index.

Science.gov (United States)

Koci, Anne Floyd; McFarlane, Judith; Nava, Angeles; Gilroy, Heidi; Maddoux, John

2012-12-01

The 49th World Health Assembly of the World Health Organization (WHO) declared violence as the leading worldwide public health problem with a focus on the increase in the incidence of injuries to women. Violence against women is an international epidemic with specific instruments required to measure the impact on women's functioning. This article describes the application of the Koci Marginality Index (KMI), a 5-item scale to measure marginality, to the baseline data of a seven-year prospective study of 300 abused women: 150 first time users of a shelter and 150 first time applicants for a protection order from the justice system. Validity and reliability of the Koci Marginality Index and its usefulness for best clinical practice and for policy decisions for abused women's health are discussed. The 49th World Health Assembly of the World Health Organization (WHO) declared violence as the leading worldwide public health problem and focused on the increase in the incidence of injuries to women (Krug et al., 2002 ). Violence against women in the form of intimate partner violence (IPV) is costly in terms of dollars and health. In the United States in 2003, estimated costs of IPV approached $8.3 billion (Centers for Disease Control and Prevention [CDC], 2011). Outcomes related to severity of IPV vary but in 2003 victims suffering severe IPV lost nearly 8 million days of paid work, and greater than 5 million days of household productivity annually (CDC, 2011). Besides the evident financial cost of IPV, research confirms that exposure to IPV impacts a woman's health immediately and in the long-term (Breiding, Black, & Ryan, 2008 ; Campbell, 2002 ; CDC, 2011). Such sequela adversely affect the health of women and may increase their marginalization, a concept akin to isolation that may further increase negative effects on health outcomes. Immigrant women are at high risk for IPV (Erez, 2002 ) and those without documentation are at higher risk for marginalization (Montalvo

Task Group on Safety Margins Action Plan (SMAP). Safety Margins Action Plan - Final Report

International Nuclear Information System (INIS)

Hrehor, Miroslav; Gavrilas, Mirela; Belac, Josef; Sairanen, Risto; Bruna, Giovanni; Reocreux, Michel; Touboul, Francoise; Krzykacz-Hausmann, B.; Park, Jong Seuk; Prosek, Andrej; Hortal, Javier; Sandervaag, Odbjoern; Zimmerman, Martin

2007-01-01

The international nuclear community has expressed concern that some changes in existing plants could challenge safety margins while fulfilling all the regulatory requirements. In 1998, NEA published a report by the Committee on Nuclear Regulatory Activities on Future Nuclear Regulatory Challenges. The report recognized 'Safety margins during more exacting operating modes' as a technical issue with potential regulatory impact. Examples of plant changes that can cause such exacting operating modes include power up-rates, life extension or increased fuel burnup. In addition, the community recognized that the cumulative effects of simultaneous changes in a plant could be larger than the accumulation of the individual effects of each change. In response to these concerns, CSNI constituted the safety margins action plan (SMAP) task group with the following objectives: 'To agree on a framework for integrated assessments of the changes to the overall safety of the plant as a result of simultaneous changes in plant operation / condition; To develop a CSNI document which can be used by member countries to assess the effect of plant change on the overall safety of the plant; To share information and experience.' The two approaches to safety analysis, deterministic and probabilistic, use different methods and have been developed mostly independently of each other. This makes it difficult to assure consistency between them. As the trend to use information on risk (where the term risk means results of the PSA/PRA analysis) to support regulatory decisions is growing in many countries, it is necessary to develop a method of evaluating safety margin sufficiency that is applicable to both approaches and, whenever possible, integrated in a consistent way. Chapter 2 elaborates on the traditional view of safety margins and the means by which they are currently treated in deterministic analyses. This chapter also discusses the technical basis for safety limits as they are used today

Validación de la escala para manía de la Universidad Nacional de Colombia usando el análisis de Rasch

Directory of Open Access Journals (Sweden)

Ricardo Sánchez

2011-03-01

Conclusiones. En este primer estudio de la escala para manías usando el análisis de Rasch, se detectó mal ajuste y redundancia de algunos ítems. El síndrome maníaco no queda completamente evaluado por la escala. El instrumento podría mejorarse agregando síntomas depresivos.

[Not Available].

Science.gov (United States)

Germán Díaz, Marta; Moreno Villares, José Manuel; Gomis Muñoz, Pilar

2016-07-19

Introducción: la nutrición parenteral domiciliaria se ha convertido en un punto clave en el tratamiento de pacientes con fracaso intestinal crónico. A pesar de los importantes avances que se han producido en las últimas décadas, tanto en los accesos vasculares, como en las soluciones empleadas, las infecciones asociadas a catéter venoso central siguen constituyendo una de las complicaciones más importantes. Dentro de las estrategias para la prevención o el tratamiento de estas infecciones se encuentra el empleo de sellados con antisépticos, como el etanol o la taurolidina, o de antibióticos.Objetivo: el objetivo de este artículo es revisar la evidencia disponible sobre el empleo de sellados con antisépticos o antibióticos en el manejo de pacientes pediátricos con nutrición parenteral domiciliaria.Material y métodos: el uso de sellados con etanol o taurolidina para prevenir el desarrollo de infecciones asociadas a catéter central estaría indicado en pacientes con nutrición parenteral domiciliaria que hayan tenido más de una infección en el año anterior o que se consideren pacientes de riesgo. Los sellados con antibióticos están indicados en el tratamiento de bacteriemias asociadas a catéter central producidas por S. coagulasa-negativo o gramnegativos, asociados a un tratamiento sistémico, siempre que sea posible, con el fin de salvar el catéter. Se debería llevar a cabo la retirada del mismo cuando existan signos de infección del punto de entrada o del trayecto subcutáneo, o cuando el germen responsable de la infección sea S. aureus o Cándida.Conclusión: a pesar de que la fuerza de la evidencia sobre la eficacia del sellado en la prevención o el tratamiento de infecciones asociadas al catéter es limitada, tanto en el niño como en el adulto, cada vez existen más datos a usar esta alternativa en pacientes con nutrición parenteral domiciliaria en los que la atención y salvaguarda de los catéteres es primordial.

Aulas-laboratorios de bajo costo, usando TIC

Directory of Open Access Journals (Sweden)

Silvia E. Calderón

2015-01-01

Full Text Available En este trabajo se presentan los resultados de una propuesta educativa orientada a promover el desarrollo de un pensamiento critico y un mayor interes por las ciencias experimentales. Con este fin desarrollamos propuestas de proyectos educativos susceptibles de ser destinadas a las aulas y laboratorios de las escuelas secundarias y primeros anos de la universidad, que resaltan los aspectos metodologicos de las ciencias. Aqui, realizamos una compilacion de varios proyectos, que ilustran formas de incorporar las tecnologias de la informacion y la comunicacion (TIC en diversos experimentos de ciencias, muchos de ellos publicados individualmente anteriormente, y que en conjunto se pueden utilizar para implementar un aula-laboratorio de bajo costo. Con TIC hacemos referencia a la convergencia de computadoras, sistemas audiovisuales, Internet, telefonia, y diversos equipos que se integran con algunos de ellos. Los proyectos intentan integrar areas como fisica, matematica, quimica, informatica, arte, etc. y apuntan a que los estudiantes puedan responder a las preguntas: .Como sabemos esto?, .Por que creemos en aquello? Preguntas que ilustran la naturaleza del pensamiento cientifico. Nuestra contribucion mas significativa es haber desarrollado ≪aulas-laboratorios≫ de muy bajo costo, usando TIC. Con el advenimiento de programas como ≪Una Laptop por Nino≫ que se estan implementando en varios paises de Latinoamerica, resulta oportuno utilizar este recurso como base para generar laboratorios de bajo costo, que creemos pueden ser una herramienta util para mejorar el aprendizaje de las ciencias, incentivar vocaciones y contribuir a desarrollar un pensamiento critico, a la par de desarrollar habilidades con el uso de las TIC que pueden ser de utilidad en diversos ambitos academicos y laborales.

Producción de carbones ultralimpios usando flotación burbujeante y lixiviación con ácidos

Directory of Open Access Journals (Sweden)

Juan Barraza

2009-01-01

Full Text Available Los carbones ultralimpios representan una importante materia prima para la elaboración de productos de alto valor agregado tales como fibra de carbono, electrodos, espumas de carbón, entre otros. En este trabajo, carbones ultralimpios con concentraciones menores a 0,50% de ceniza (p/p, base seca, bs se obtuvieron usando flotación burbujeante en columna y lixiviación con ácidos fluorhídrico (HF y nítrico (HNO3. Los contenidos de ceniza se redujeron desde 19,60 % en los carbones alimentados hasta 8,70 % en los carbones flotados usando tres etapas en serie en una columna de flotación. Al usar lixiviación química con HF 7,53M y HNO3 2,3M, los carbones presentaron contenidos de 1,42% de ceniza, 0,86% de azufre y 2,00% de materia mineral, mientras que cuando se usó un proceso combinado de flotación seguido de lixiviación ácida con HF 19,2M y HNO3 8,12M se obtuvo un carbón con 0,48 % de ceniza 0,71 % de azufre y 0,96 % de materia mineral. Sin embargo, al usar carbón original (no flotado a las mismas concentraciones ácidas utilizadas en el proceso combinado se produjo un carbón ultralimpio de contenido de ceniza 0,33%.

Margin improvement initiatives: realistic approaches

Energy Technology Data Exchange (ETDEWEB)

Chan, P.K.; Paquette, S. [Royal Military College of Canada, Chemistry and Chemical Engineering Dept., Kingston, ON (Canada); Cunning, T.A. [Department of National Defence, Ottawa, ON (Canada); French, C.; Bonin, H.W. [Royal Military College of Canada, Chemistry and Chemical Engineering Dept., Kingston, ON (Canada); Pandey, M. [Univ. of Waterloo, Waterloo, ON (Canada); Murchie, M. [Cameco Fuel Manufacturing, Port Hope, ON (Canada)

2014-07-01

With reactor core aging, safety margins are particularly tight. Two realistic and practical approaches are proposed here to recover margins. The first project is related to the use of a small amount of neutron absorbers in CANDU Natural Uranium (NU) fuel bundles. Preliminary results indicate that the fuelling transient and subsequent reactivity peak can be lowered to improve the reactor's operating margins, with minimal impact on burnup when less than 1000 mg of absorbers is added to a fuel bundle. The second project involves the statistical analysis of fuel manufacturing data to demonstrate safety margins. Probability distributions are fitted to actual fuel manufacturing datasets provided by Cameco Fuel Manufacturing, Inc. They are used to generate input for ELESTRES and ELOCA. It is found that the fuel response distributions are far below industrial failure limits, implying that margin exists in the current fuel design. (author)

The marginal costs of greenhouse gas emissions

International Nuclear Information System (INIS)

Tol, R.S.J.

1999-01-01

Estimates of the marginal costs of greenhouse gas emissions are on important input to the decision how much society would want to spend on greenhouse gas emission reduction. Marginal cost estimates in the literature range between $5 and $25 per ton of carbon. Using similar assumptions, the FUND model finds marginal costs of $9--23/tC, depending on the discount rate. If the aggregation of impacts over countries accounts for inequalities in income distribution or for risk aversion, marginal costs would rise by about a factor of 3. Marginal costs per region are an order of magnitude smaller than global marginal costs. The ratios between the marginal costs of CO 2 and those of CH 4 and N 2 O are roughly equal to the global warming potentials of these gases. The uncertainty about the marginal costs is large and right-skewed. The expected value of the marginal costs lies about 35% above the best guess, the 95-percentile about 250%

Refining margins: recent trends

International Nuclear Information System (INIS)

Baudoin, C.; Favennec, J.P.

1999-01-01

Despite a business environment that was globally mediocre due primarily to the Asian crisis and to a mild winter in the northern hemisphere, the signs of improvement noted in the refining activity in 1996 were borne out in 1997. But the situation is not yet satisfactory in this sector: the low return on invested capital and the financing of environmental protection expenditure are giving cause for concern. In 1998, the drop in crude oil prices and the concomitant fall in petroleum product prices was ultimately rather favorable to margins. Two elements tended to put a damper on this relative optimism. First of all, margins continue to be extremely volatile and, secondly, the worsening of the economic and financial crisis observed during the summer made for a sharp decline in margins in all geographic regions, especially Asia. Since the beginning of 1999, refining margins are weak and utilization rates of refining capacities have decreased. (authors)

Producción de carbones ultralimpios usando flotación burbujeante y lixiviación con ácidos

OpenAIRE

Barraza, Juan; Mejía, Isabel

2009-01-01

Los carbones ultralimpios representan una importante materia prima para la elaboración de productos de alto valor agregado tales como fibra de carbono, electrodos, espumas de carbón, entre otros. En este trabajo, carbones ultralimpios con concentraciones menores a 0,50% de ceniza (p/p, base seca, bs) se obtuvieron usando flotación burbujeante en columna y lixiviación con ácidos fluorhídrico (HF) y nítrico (HNO3). Los contenidos de ceniza se redujeron desde 19,60 % en los carbones alimentados ...

Margin Requirements and Equity Option Returns

DEFF Research Database (Denmark)

Hitzemann, Steffen; Hofmann, Michael; Uhrig-Homburg, Marliese

In equity option markets, traders face margin requirements both for the options themselves and for hedging-related positions in the underlying stock market. We show that these requirements carry a significant margin premium in the cross-section of equity option returns. The sign of the margin...... premium depends on demand pressure: If end-users are on the long side of the market, option returns decrease with margins, while they increase otherwise. Our results are statistically and economically significant and robust to different margin specifications and various control variables. We explain our...... findings by a model of funding-constrained derivatives dealers that require compensation for satisfying end-users’ option demand....

Margin Requirements and Equity Option Returns

DEFF Research Database (Denmark)

Hitzemann, Steffen; Hofmann, Michael; Uhrig-Homburg, Marliese

In equity option markets, traders face margin requirements both for the options themselves and for hedging-related positions in the underlying stock market. We show that these requirements carry a significant "margin premium" in the cross-section of equity option returns. The sign of the margin...... premium depends on demand pressure: If end-users are on the long side of the market, option returns decrease with margins, while they increase otherwise. Our results are statistically and economically significant and robust to different margin specifications and various control variables. We explain our...... findings by a model of funding-constrained derivatives dealers that require compensation for satisfying end-users’ option demand....

Decoding the Margins: What Can the Fractal Geometry of Basaltic Flow Margins Tell Us?

Science.gov (United States)

Schaefer, E. I.; Hamilton, C.; Neish, C.; Beard, S. P.; Bramson, A. M.; Sori, M.; Rader, E. L.

2016-12-01

Studying lava flows on other planetary bodies is essential to characterizing eruption styles and constraining the bodies' thermal evolution. Although planetary basaltic flows are common, many key features are not resolvable in orbital imagery. We are thus developing a technique to characterize basaltic flow type, sub-meter roughness, and sediment mantling from these data. We will present the results from upcoming fieldwork at Craters of the Moon National Monument and Preserve with FINESSE (August) and at Hawai'i Volcanoes National Park (September). We build on earlier work that showed that basaltic flow margins are approximately fractal [Bruno et al., 1992; Gaonac'h et al., 1992] and that their fractal dimensions (D) have distinct `a`ā and pāhoehoe ranges under simple conditions [Bruno et al., 1994]. Using a differential GPS rover, we have recently shown that the margin of Iceland's 2014 Holuhraun flow exhibits near-perfect (R2=0.9998) fractality for ≥24 km across dm to km scales [Schaefer et al., 2016]. This finding suggests that a fractal-based technique has significant potential to characterize flows at sub-resolution scales. We are simultaneously seeking to understand how margin fractality can be modified. A preliminary result for an `a'ā flow in Hawaii's Ka'ū Desert suggests that although aeolian mantling obscures the original flow margin, the apparent margin (i.e., sediment-lava interface) remains fractal [Schaefer et al., 2015]. Further, the apparent margin's D is likely significantly modified from that of the original margin. Other factors that we are exploring include erosion, transitional flow types, and topographic confinement. We will also rigorously test the intriguing possibility that margin D correlates with the sub-meter Hurst exponent H of the flow surface, a common metric of roughness scaling [e.g., Shepard et al., 2001]. This hypothesis is based on geometric arguments [Turcotte, 1997] and is qualitatively consistent with all results so far.

SÍNTESIS DE OXITOCINA EN FASE SÓLIDA USANDO DERIVADOS DE TERBUTOXICARBONILO Y FLUORENILMETOXICARBONILO

Directory of Open Access Journals (Sweden)

Julio C Calvo

2010-08-01

Full Text Available La oxitocina, péptido cíclico cuya secuencia es CYIQNCPLG, fué el primer péptido de importancia biológica que pudo ser sintetizado. En este trabajo se compara la síntesis de la oxitocina usando resina p metilbenzhidrilamina (MBHA para la síntesis por estrategia t-Boc y resina Rink p-metilbenzhidrilamina (Rink MBHA para la síntesis por estrategia Fmoc, con altos rendimientos. El péptido crudo se ciclizó en una disolución acuosa de dimetilsulfóxido al 10%. La caracterización se llevó a cabo por espectrometría de masas y resonancia magnética nuclear, y se logró detectar la presencia de dos isómeros.

Transmisión de audio usando redes Zigbee

Directory of Open Access Journals (Sweden)

David Delgado León

2011-03-01

Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Zigbee es un protocolo de comunicaciones basado en el estándar para redes inalámbricas IEEE_802.15.4. Concebido para el control y la monitorización de redes de sensores tanto en entornos industriales, médicos, como domóticos, ha existido un creciente interés por evaluarlo en aplicaciones de multimedia. Aun sin garantizar QoS (Quality of service por su limitado ancho de banda existen un conjunto de aplicaciones para vigilancia, grupos de rescate y salvamento, seguridad en entornos domóticos, grupos desplegados en un área limitada con necesidad de comunicación donde un sistema de audio y video en tiempo real de bajo costo basado en tecnología Zigbee es una idea sumamente atractiva.   Se presenta el diseño de un sistema que permita la comunicación de un grupo de usuarios desplegadas en un área limitada. Utiliza Microcontroladores RISC y tecnología Zigbee. Se investiga la factibilidad de usar la tecnología Zigbee para la transmisión de audio, se analizan

Splenic marginal zone lymphoma.

Science.gov (United States)

Piris, Miguel A; Onaindía, Arantza; Mollejo, Manuela

Splenic marginal zone lymphoma (SMZL) is an indolent small B-cell lymphoma involving the spleen and bone marrow characterized by a micronodular tumoral infiltration that replaces the preexisting lymphoid follicles and shows marginal zone differentiation as a distinctive finding. SMZL cases are characterized by prominent splenomegaly and bone marrow and peripheral blood infiltration. Cells in peripheral blood show a villous cytology. Bone marrow and peripheral blood characteristic features usually allow a diagnosis of SMZL to be performed. Mutational spectrum of SMZL identifies specific findings, such as 7q loss and NOTCH2 and KLF2 mutations, both genes related with marginal zone differentiation. There is a striking clinical variability in SMZL cases, dependent of the tumoral load and performance status. Specific molecular markers such as 7q loss, p53 loss/mutation, NOTCH2 and KLF2 mutations have been found to be associated with the clinical variability. Distinction from Monoclonal B-cell lymphocytosis with marginal zone phenotype is still an open issue that requires identification of precise and specific thresholds with clinical meaning. Copyright © 2016 Elsevier Ltd. All rights reserved.

Categorical marginal models: quite extensive package for the estimation of marginal models for categorical data

OpenAIRE

Wicher Bergsma; Andries van der Ark

2015-01-01

A package accompanying the book Marginal Models for Dependent, Clustered, and Longitudinal Categorical Data by Bergsma, Croon, & Hagenaars, 2009. It’s purpose is fitting and testing of marginal models.

Characterizing Convexity of Games using Marginal Vectors

NARCIS (Netherlands)

van Velzen, S.; Hamers, H.J.M.; Norde, H.W.

2003-01-01

In this paper we study the relation between convexity of TU games and marginal vectors.We show that if specfic marginal vectors are core elements, then the game is convex.We characterize sets of marginal vectors satisfying this property, and we derive the formula for the minimum number of marginal

12 CFR 220.4 - Margin account.

Science.gov (United States)

2010-01-01

... Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM CREDIT BY... securities. The required margin on a net long or net short commitment in a when-issued security is the margin...) Interest charged on credit maintained in the margin account; (ii) Premiums on securities borrowed in...

Conference Report: The New Discovery of Margins: Theory-Based Excursions in Marginal Social Fields

Directory of Open Access Journals (Sweden)

Babette Kirchner

2014-05-01

Full Text Available At this year's spring conference of the Sociology of Knowledge Section of the German Sociological Association, a diverse range of theoretical concepts and multiple empirical insights into different marginal social fields were presented. As in everyday life, drawing a line between center and margin can be seen as an important challenge that must equally be faced in sociology. The socially constructed borderline appears to be highly variable. Therefore it has to be delineated or fixed somehow. The construction of margins is necessary for society in general and smaller social groupings alike to confirm one's own "normal" identity, or one's own membership on the fringes. The different contributions exemplify what was established at the beginning of the conference: Namely that society and its margins are defined differently according to the empirical as well as conceptual focus. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1402148

NRC Seismic Design Margins Program Plan

International Nuclear Information System (INIS)

Cummings, G.E.; Johnson, J.J.; Budnitz, R.J.

1985-08-01

Recent studies estimate that seismically induced core melt comes mainly from earthquakes in the peak ground acceleration range from 2 to 4 times the safe shutdown earthquake (SSE) acceleration used in plant design. However, from the licensing perspective of the US Nuclear Regulatory Commission, there is a continuing need for consideration of the inherent quantitative seismic margins because of, among other things, the changing perceptions of the seismic hazard. This paper discusses a Seismic Design Margins Program Plan, developed under the auspices of the US NRC, that provides the technical basis for assessing the significance of design margins in terms of overall plant safety. The Plan will also identify potential weaknesses that might have to be addressed, and will recommend technical methods for assessing margins at existing plants. For the purposes of this program, a general definition of seismic design margin is expressed in terms of how much larger that the design basis earthquake an earthquake must be to compromise plant safety. In this context, margin needs to be determined at the plant, system/function, structure, and component levels. 14 refs., 1 fig

Medición de microdeformaciones en losas viales usando sensores de redes de Bragg en fibras ópticas

OpenAIRE

Vélez-Hoyos, Francisco Javier; Serpa-Imbet, Claudia Milena; Gómez-Cardona, Nelson Darío

2010-01-01

En este trabajo se presenta un método no invasivo para la medición de microdeformaciones en estructuras de concreto usando sensores de redes de Bragg en fibras ópticas adheridos a su superficie. Se realizan mediciones en losas viales de concreto bajo una carga estática de 10 kN, encontrándose una relación aproximada de 2 : 1 entre la deformación registrada por los sensores y los valores arrojados por una simulación computacional con el método de elementos finitos. Se propone el uso de estos s...

The marginal band system in nymphalid butterfly wings.

Science.gov (United States)

Taira, Wataru; Kinjo, Seira; Otaki, Joji M

2015-01-01

Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.

Assessment of seismic margin calculation methods

International Nuclear Information System (INIS)

Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.

1989-03-01

Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs

MARGINS: Toward a novel science plan

Science.gov (United States)

Mutter, John C.

A science plan to study continental margins has been in the works for the past 3 years, with almost 200 Earth scientists from a wide variety of disciplines gathering at meetings and workshops. Most geological hazards and resources are found at continental margins, yet our understanding of the processes that shape the margins is meager.In formulating this MARGINS research initiative, fundamental issues concerning our understanding of basic Earth-forming processes have arisen. It is clear that a business-as-usual approach will not solve the class of problems defined by the MARGINS program; the solutions demand approaches different from those used in the past. In many cases, a different class of experiment will be required, one that is well beyond the capability of individual principle investigators to undertake on their own. In most cases, broadly based interdisciplinary studies will be needed.

Reliabilityy and operating margins of LWR fuels

International Nuclear Information System (INIS)

Strasser, A.A.; Lindquist, K.O.

1977-01-01

The margins to fuel thermal operating limits under normal and accident conditions are key to plant operating flexibility and impact on availability and capacity factor. Fuel performance problems that do not result in clad breach, can reduce these margins. However, most have or can be solved with design changes. Regulatory changes have been major factors in eroding these margins. Various methods for regaining the margins are discussed

Marginal cost application in the power industry

International Nuclear Information System (INIS)

Twardy, L.; Rusak, H.

1994-01-01

Two kind of marginal costs, the short-run and the long-run, are defined. The former are applied in conditions when the load increase is not accompanied neither by the increase of the transmission capacity not the installed capacity while the latter assume new investments to expand the power system. The long-run marginal costs be used to forecast optimized development of the system. They contain two main components: the marginal costs of capacity and the marginal costs of energy. When the long-run marginal costs are calculated, each component is considered for particular voltage levels, seasons of the year, hours of the day - selected depending on the system reliability factor as well as on its load level. In the market economy countries the long-run marginal costs can be used for setting up the electric energy tariffs. (author). 7 refs, 11 figs

Lei da gravitação universal e os satélites: uma abordagem histórico-temática usando multimídia

Directory of Open Access Journals (Sweden)

Elvis Vilela Rodrigues

2012-01-01

Full Text Available Examina-se, neste artigo, o desenvolvimento de aulas de Física em que, usando-se uma multimídia, a Lei da Gravitação Universal é abordada de forma contextualizada a partir da História da Ciência e de um tema atual (os satélites. O objetivo foi examinar como estudantes de Ensino Médio aceitam e se envolvem nesse estudo. Usando uma abordagem metodológica qualitativa, a multimídia apresenta o que são e como funcionam os satélites artificiais, trazendo uma narrativa histórica desde as ideias de movimento do sistema planetário de Ptolomeu até as de Isaac Newton sobre o movimento dos corpos, culminando na Lei da Gravitação Universal. Entrevistas, observações de sala de aula e documentos produzidos pelos estudantes mostram que as imagens, os filmes e os textos contidos na multimídia enriquecem, de modo significativo, o conteúdo, facilitando o entendimento de conceitos da Física. A contextualização histórico-temática, por sua vez, produz maior envolvimento dos alunos no estudo da Física.

IMPLEMENTACIÓN DE UN SERVICIO EN LA WEB –MASHUP– PARA LA FUSIÓN DE IMÁGENES SATELITALES USANDO LA TRANSFORMADA RÁPIDA DE WAVELET HAAR

Directory of Open Access Journals (Sweden)

Rubén Medina

2014-05-01

Full Text Available En este artículo se implementa un nuevo servicio en la Web que ofrece a los usuarios la posibilidad de realizar la fusión de imágenes de satélite provenientes de diferentes sensores remotos y/o con diferentes resoluciones espaciales. A lo largo del artículo tres temáticas importantes son abordadas. La primera temática corresponde al servicio Web, éste servicio es implementado usando software libre y cuenta con una sencilla interfaz donde el usuario puede interactuar y principalmente puede realizar una solicitud del servicio de fusión. Adicionalmente, en la aplicación Web se desarrolló un módulo que permite obtener datos georreferenciados de diferentes fuentes externas para crear un nuevo servicio (Mashup a través de las API’s, de manera rápida y fácil utilizando OpenStreetMaps. La segunda temática se ocupa del análisis de la transformada rápida de wavelet haar (TRWH, estos conceptos matemáticos se abordan a partir de un ejemplo usando una matriz que se descompone en coeficientes de detalle y de aproximación de segundo nivel. La última temática detalla la metodología propuesta, paso a paso, para realizar la fusión de imágenes usando la TRWH. Igualmente con el fin de determinar la eficiencia de la TRWH cinco wavelets diferentes fueron implementadas en Matlab para fusionar el mismo par de imágenes satelitales. Las imágenes resultantes fueron evaluadas tanto en la calidad espacial como en la espectral a través de cuatro índices. Los mejores resultados de la evaluación fueron obtenidos con la TRWH la cual preserva la riqueza espectral de la imagen multiespectral original y mejora su calidad espacial.

Workers' marginal costs of commuting

DEFF Research Database (Denmark)

van Ommeren, Jos; Fosgerau, Mogens

2009-01-01

This paper applies a dynamic search model to estimate workers' marginal costs of commuting, including monetary and time costs. Using data on workers' job search activity as well as moving behaviour, for the Netherlands, we provide evidence that, on average, workers' marginal costs of one hour...

Pathology of nodal marginal zone lymphomas.

Science.gov (United States)

Pileri, Stefano; Ponzoni, Maurilio

Nodal marginal zone B cell lymphomas (NMZLs) are a rare group of lymphoid disorders part of the spectrum of marginal zone B-cell lymphomas, which encompass splenic marginal one B-cell lymphoma (SMZL) and extra nodal marginal zone of B-cell lymphoma (EMZL), often of MALT-type. Two clinicopathological forms of NMZL are recognized: adult-type and pediatric-type, respectively. NMZLs show overlapping features with other types of MZ, but distinctive features as well. In this review, we will focus on the salient distinguishing features of NMZL mostly under morphological/immunophenotypical/molecular perspectives in views of the recent acquisitions and forthcoming updated 2016 WHO classification of lymphoid malignancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biodiversity and agro-ecology in field margins.

Science.gov (United States)

De Cauwer, B; Reheul, D; Nijs, I; Milbau, A

2005-01-01

This multidisciplinary study investigates agro-ecological functions (nature conservation, agriculture, environment) and implications of newly created, mown sown and unsown field margin strips installed on ex-arable land to increase biodiversity. From conservational concern, the development of species rich field margin strips was not strongly affected by the installed type of margin strip since species diversity converged over time, whether strips were sown or not. Convergence between unsown and sown margin strips occurred also in terms of species composition: unsown and sown strips became similar over time. Mowing without removal of cuttings significantly reduced species richness, yielded more grassy margin strips and delayed similarity in species composition between sown and unsown margin strips. Species richness on the longer term was not significantly affected by light regime nor by disturbance despite significant temporary effects shortly after the disturbance event. On the contrary vegetation composition in terms of importance of functional groups changed after disturbance: the share of spontaneous species within functional groups increased resulting in higher similarity between the sown and unsown vegetation. Furthermore risk of invasion was highest in the disturbed unsown community on the unshaded side of a tree lane. A positive effect of botanical diversity on insect number and diversity was found. However the effects of botanical diversity on insect number was mediated by light regime. At high light availability differences between plant communities were more pronounced compared to low light availablilty. The abundance of some insect families was dependent on the vegetation composition. Furthermore light availability significantly influenced insect diversity as well as the spatial distribution of families. From agricultural concern, installing margin strips by sowing a species mixture and a mowing regime with removal of cuttings are good practices to

Risk insights from seismic margin reviews

International Nuclear Information System (INIS)

Budnitz, R.J.

1990-01-01

This paper discusses the information that has been derived from the three seismic-margin reviews conducted so far, and the information that is potentially available from using the seismic-margin method more generally. There are two different methodologies for conducting seismic margin reviews of nuclear power plants, one developed under NRC sponsorship and one developed under sponsorship of the Electric Power Research Institute. Both methodologies will be covered in this paper. The paper begins with a summary of the steps necessary to complete a margin review, and will then outline the key technical difficulties that need to be addressed. After this introduction, the paper covers the safety and operational insights derived from the three seismic-margin reviews already completed: the NRC-sponsored review at Maine Yankee; the EPRI-sponsored review at Catawba; and the joint EPRI/NRC/utility effort at Hatch. The emphasis is on engineering insights, with attention to the aspects of the reviews that are easiest to perform and that provide the most readily available insights

Exactly marginal deformations from exceptional generalised geometry

Energy Technology Data Exchange (ETDEWEB)

Ashmore, Anthony [Merton College, University of Oxford,Merton Street, Oxford, OX1 4JD (United Kingdom); Mathematical Institute, University of Oxford,Andrew Wiles Building, Woodstock Road, Oxford, OX2 6GG (United Kingdom); Gabella, Maxime [Institute for Advanced Study,Einstein Drive, Princeton, NJ 08540 (United States); Graña, Mariana [Institut de Physique Théorique, CEA/Saclay,91191 Gif-sur-Yvette (France); Petrini, Michela [Sorbonne Université, UPMC Paris 05, UMR 7589, LPTHE,75005 Paris (France); Waldram, Daniel [Department of Physics, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom)

2017-01-27

We apply exceptional generalised geometry to the study of exactly marginal deformations of N=1 SCFTs that are dual to generic AdS{sub 5} flux backgrounds in type IIB or eleven-dimensional supergravity. In the gauge theory, marginal deformations are parametrised by the space of chiral primary operators of conformal dimension three, while exactly marginal deformations correspond to quotienting this space by the complexified global symmetry group. We show how the supergravity analysis gives a geometric interpretation of the gauge theory results. The marginal deformations arise from deformations of generalised structures that solve moment maps for the generalised diffeomorphism group and have the correct charge under the generalised Reeb vector, generating the R-symmetry. If this is the only symmetry of the background, all marginal deformations are exactly marginal. If the background possesses extra isometries, there are obstructions that come from fixed points of the moment maps. The exactly marginal deformations are then given by a further quotient by these extra isometries. Our analysis holds for any N=2 AdS{sub 5} flux background. Focussing on the particular case of type IIB Sasaki-Einstein backgrounds we recover the result that marginal deformations correspond to perturbing the solution by three-form flux at first order. In various explicit examples, we show that our expression for the three-form flux matches those in the literature and the obstruction conditions match the one-loop beta functions of the dual SCFT.

RISK-INFORMED SAFETY MARGIN CHARACTERIZATION

International Nuclear Information System (INIS)

Dinh, Nam; Szilard, Ronaldo

2009-01-01

The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system's 'loading' and its 'capacity', plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons

Professional Commitment and Professional Marginalism in Teachers

Directory of Open Access Journals (Sweden)

Kalashnikov A.I.

2017-11-01

Full Text Available The article reviews teachers' attitudes towards the teaching profession which can be expressed both in professional commitment and in professional marginalism. The dominance of professional marginalism could affect destructively the students as well as the teacher’s personality, hence the issues related to the content of personal position of a marginal and the rate of marginalism among teachers. It was suggested that marginalism could be revealed in the study of professional commitment. The study involved 81 teachers of Sverdlovsk secondary schools aged 21—60 years with work experience ranging from 1 month to 39 years. The Professional Commitment Questionnaire was used as the study technique. The results showed that negative emotional attitude towards the profession and reluctance to leave the profession were grouped as a separate factor. The dispersion factor was 12,5%. The factor loadings ranged from 0.42 to 0.84. The study proved that professional marginalism in teachers includes dissatisfaction with work, feelings of resentment against profession and an unwillingness to leave the profession.

A quantitative analysis of transtensional margin width

Science.gov (United States)

Jeanniot, Ludovic; Buiter, Susanne J. H.

2018-06-01

Continental rifted margins show variations between a few hundred to almost a thousand kilometres in their conjugated widths from the relatively undisturbed continent to the oceanic crust. Analogue and numerical modelling results suggest that the conjugated width of rifted margins may have a relationship to their obliquity of divergence, with narrower margins occurring for higher obliquity. We here test this prediction by analysing the obliquity and rift width for 26 segments of transtensional conjugate rifted margins in the Atlantic and Indian Oceans. We use the plate reconstruction software GPlates (http://www.gplates.org) for different plate rotation models to estimate the direction and magnitude of rifting from the initial phases of continental rifting until breakup. Our rift width corresponds to the distance between the onshore maximum topography and the last identified continental crust. We find a weak positive correlation between the obliquity of rifting and rift width. Highly oblique margins are narrower than orthogonal margins, as expected from analogue and numerical models. We find no relationships between rift obliquities and rift duration nor the presence or absence of Large Igneous Provinces (LIPs).

On the evaluation of marginal expected shortfall

DEFF Research Database (Denmark)

Caporin, Massimiliano; Santucci de Magistris, Paolo

2012-01-01

In the analysis of systemic risk, Marginal Expected Shortfall may be considered to evaluate the marginal impact of a single stock on the market Expected Shortfall. These quantities are generally computed using log-returns, in particular when there is also a focus on returns conditional distribution....... In this case, the market log-return is only approximately equal to the weighed sum of equities log-returns. We show that the approximation error is large during turbulent market phases, with a subsequent impact on Marginal Expected Shortfall. We then suggest how to improve the evaluation of Marginal Expected...

[Resection margins in conservative breast cancer surgery].

Science.gov (United States)

Medina Fernández, Francisco Javier; Ayllón Terán, María Dolores; Lombardo Galera, María Sagrario; Rioja Torres, Pilar; Bascuñana Estudillo, Guillermo; Rufián Peña, Sebastián

2013-01-01

Conservative breast cancer surgery is facing a new problem: the potential tumour involvement of resection margins. This eventuality has been closely and negatively associated with disease-free survival. Various factors may influence the likelihood of margins being affected, mostly related to the characteristics of the tumour, patient or surgical technique. In the last decade, many studies have attempted to find predictive factors for margin involvement. However, it is currently the new techniques used in the study of margins and tumour localisation that are significantly reducing reoperations in conservative breast cancer surgery. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

Ferritin associates with marginal band microtubules

International Nuclear Information System (INIS)

Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich

2007-01-01

We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir

Methylation patterns in marginal zone lymphoma.

Science.gov (United States)

Arribas, Alberto J; Bertoni, Francesco

Promoter DNA methylation is a major regulator of gene expression and transcription. The identification of methylation changes is important for understanding disease pathogenesis, for identifying prognostic markers and can drive novel therapeutic approaches. In this review we summarize the current knowledge regarding DNA methylation in MALT lymphoma, splenic marginal zone lymphoma, nodal marginal zone lymphoma. Despite important differences in the study design for different publications and the existence of a sole large and genome-wide methylation study for splenic marginal zone lymphoma, it is clear that DNA methylation plays an important role in marginal zone lymphomas, in which it contributes to the inactivation of tumor suppressors but also to the expression of genes sustaining tumor cell survival and proliferation. Existing preclinical data provide the rationale to target the methylation machinery in these disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Limitations of ''margin'' in qualification tests

International Nuclear Information System (INIS)

Clough, R.L.; Gillen, K.T.

1984-01-01

We have carried out investigations of polymer radiation degradation behaviors which have brought to light a number of reasons why this concept of margin can break down. First of all, we have found that dose-rate effects vary greatly in magnitude. Thus, based on high dose-rate testing, poor materials with large dose-rate effects may be selected over better materials with small effects. Also, in certain cases, material properties have been found to level out (as with PVC) or reverse trend (as with buna-n) at high doses, so that ''margin'' may be ineffective, misleading, or counterproductive. For Viton, the material properties were found to change in opposite directions at high and low dose rates, making ''margin'' inappropriate. The underlying problem with the concept of ''margin'' is that differences in aging conditions can lead to fundamental differences in degradation mechanisms

Silenced, Silence, Silent: Motherhood in the Margins

Science.gov (United States)

Carpenter, Lorelei; Austin, Helena

2007-01-01

This project explores the experiences of women who mother children with ADHD. The authors use the metaphor of the text and the margin. The text is the "motherhood myth" that describes a particular sort of "good" mothering. The margin is the space beyond that text. This marginal space is inhabited by some or all of the mothers they spoke with, some…

Continental transform margins : state of art and future milestones

Science.gov (United States)

Basile, Christophe

2010-05-01

Transform faults were defined 45 years ago as ‘a new class of fault' (Wilson, 1965), and transform margins were consequently individualized as a new class of continental margins. While transform margins represent 20 to 25 % of the total length of continent-ocean transitions, they were poorly studied, especially when compared with the amount of data, interpretations, models and conceptual progress accumulated on divergent or convergent continental margins. The best studied examples of transform margins are located in the northern part of Norway, south of South Africa, in the gulf of California and on both sides of the Equatorial Atlantic. Here is located the Côte d'Ivoire - Ghana margin, where the more complete data set was acquired, based on numerous geological and geophysical cruises, including ODP Leg 159. The first models that encompassed the structure and evolution of transform margins were mainly driven by plate kinematic reconstructions, and evidenced the diachronic end of tectonic activity and the non-cylindrical character of these margins, with a decreasing strike-slip deformation from the convex to the concave divergent-transform intersections. Further thermo-mechanical models were more specifically designed to explain the vertical displacements along transform margins, and especially the occurrence of high-standing marginal ridges. These thermo-mechanical models involved either heat transfer from oceanic to continental lithospheres across the transform faults or tectonically- or gravity-driven mass transfer in the upper crust. These models were far from fully fit observations, and were frequently dedicated to specific example, and not easily generalizable. Future work on transform continental margins may be expected to fill some scientific gaps, and the definition of working directions can benefit from the studies dedicated to other types of margins. At regional scale the structural and sedimentological variability of transform continental margins has

Aspects of marginal expenditures in energy sector

International Nuclear Information System (INIS)

Stojchev, D.; Kynev, K.

1994-01-01

Technical and economical problems of marginal analysis methodology, its application procedure in energy sector and marginal expenditures determination are outlined. A comparative characteristics of the application is made for different periods of time. The differences in calculation of the marginal expenditures and prices are discussed. The operational costs, investments and inflation are analyzed. The mechanism of application of this approach in different planing horizon is outlined. The role of the change in the costs in time, the time unit, volume, the scope of application, etc. are determined. The areas of transition from one to other form of marginal expenditures are shown. 4 refs. (orig.)

Characterizing entanglement with global and marginal entropic measures

International Nuclear Information System (INIS)

Adesso, Gerardo; Illuminati, Fabrizio; De Siena, Silvio

2003-01-01

We qualify the entanglement of arbitrary mixed states of bipartite quantum systems by comparing global and marginal mixednesses quantified by different entropic measures. For systems of two qubits we discriminate the class of maximally entangled states with fixed marginal mixednesses, and determine an analytical upper bound relating the entanglement of formation to the marginal linear entropies. This result partially generalizes to mixed states the quantification of entanglement with marginal mixednesses holding for pure states. We identify a class of entangled states that, for fixed marginals, are globally more mixed than product states when measured by the linear entropy. Such states cannot be discriminated by the majorization criterion

Steel Industry Marginal Opportunity Analysis

Energy Technology Data Exchange (ETDEWEB)

none,

2005-09-01

The Steel Industry Marginal Opportunity Analysis (PDF 347 KB) identifies opportunities for developing advanced technologies and estimates both the necessary funding and the potential payoff. This analysis determines what portion of the energy bandwidth can be captured through the adoption of state-of-the-art technology and practices. R&D opportunities for addressing the remainder of the bandwidth are characterized and plotted on a marginal opportunity curve.

Steep microbial boundstone-dominated plaform margins

NARCIS (Netherlands)

Kenter, J.A.M.; Harris, P.M.; Della Porta, G.P.

2005-01-01

Seaward progradation of several kilometers has been documented mostly for leeward margin low-angle carbonate slope systems with a dominant platform top sediment source. However, steep and high-relief margins fronting deep basins can also prograde and as such are somewhat perplexing. Characteristics

Conference Report: The New Discovery of Margins: Theory-Based Excursions in Marginal Social Fields

OpenAIRE

Kirchner, Babette; Lorenzen, Jule-Marie; Striffler, Christine

2014-01-01

At this year's spring conference of the Sociology of Knowledge Section of the German Sociological Association, a diverse range of theoretical concepts and multiple empirical insights into different marginal social fields were presented. As in everyday life, drawing a line between center and margin can be seen as an important challenge that must equally be faced in sociology. The socially constructed borderline appears to be highly variable. Therefore it has to be delineated or fixed somehow. ...

Evaluating the marginal utility principle for long-term hydropower scheduling

International Nuclear Information System (INIS)

Zhao, Tongtiegang; Zhao, Jianshi; Liu, Pan; Lei, Xiaohui

2015-01-01

Highlights: • Analysis of one-, two- and multi-period hydropower scheduling. • Derivation of marginal cost and marginal return of carry-over storage. • Evaluation of the marginal utility principle in a case study of the Three Gorges Reservoir. - Abstract: The conversion of the potential energy of dammed water into hydropower depends on both reservoir storage and release, which are the major difficulties in hydropower reservoir operation. This study evaluates the marginal utility principle, which determines the optimal carry-over storage between periods, for long-term hydropower scheduling. Increasing marginal cost and decreasing marginal return are two important characteristics that determine the marginal utility principle in water supply. However, the notion of decreasing marginal return is inapplicable in hydropower scheduling. Instead, the carry-over storage from one period has an increasing marginal contribution to the power generation in the next period. Although carry-over storage incurs an increasing marginal cost to the power generation in the current period, the marginal return is higher than the marginal cost. The marginal return from the carry-over storage further increases in the multi-period case. These findings suggest saving as much carry-over storage as possible, which is bounded by the operational constraints of storage capacity, environmental flow, and installed capacity in actual hydropower scheduling. The marginal utility principle is evaluated for a case study of the Three Gorges Reservoir, and the effects of the constraints are discussed. Results confirm the theoretical findings and show that the marginal return from carry-over storage is larger than the marginal cost. The operational constraints help determine the optimal carry-over storage.

Sobre el estudio de la función cuadrática y su relación con el área de algunas figuras y su visualización usando Cabri II Plus

OpenAIRE

Vera Barrios, Dídimo

2013-01-01

Propuesta didáctica en donde se presentan algunas actividades dinámicas usando Cabri II Plus con el fin de relacionar algunos aspectos que tienen que ver con el área de algunas figuras y la función cuadrática.

From Borders to Margins

DEFF Research Database (Denmark)

Parker, Noel

2009-01-01

of entities that are ever open to identity shifts.  The concept of the margin possesses a much wider reach than borders, and focuses continual attention on the meetings and interactions between a range of indeterminate entities whose interactions may determine both themselves and the types of entity...... upon Deleuze's philosophy to set out an ontology in which the continual reformulation of entities in play in ‘post-international' society can be grasped.  This entails a strategic shift from speaking about the ‘borders' between sovereign states to referring instead to the ‘margins' between a plethora...

Mental Depreciation and Marginal Decision Making

Science.gov (United States)

Heath; Fennema

1996-11-01

We propose that individuals practice "mental depreciation," that is, they implicitly spread the fixed costs of their expenses over time or use. Two studies explore how people spread fixed costs on durable goods. A third study shows that depreciation can lead to two distinct errors in marginal decisions: First, people sometimes invest too much effort to get their money's worth from an expense (e.g., they may use a product a lot to spread the fixed expense across more uses). Second, people sometimes invest too little effort to get their money's worth: When people add a portion of the fixed cost to the current costs, their perceived marginal (i.e., incremental) costs exceed their true marginal costs. In response, they may stop investing because their perceived costs surpass the marginal benefits they are receiving. The latter effect is supported by two field studies that explore real board plan decisions by university students.

Marginal and Interaction Effects in Ordered Response Models

OpenAIRE

Debdulal Mallick

2009-01-01

In discrete choice models the marginal effect of a variable of interest that is interacted with another variable differs from the marginal effect of a variable that is not interacted with any variable. The magnitude of the interaction effect is also not equal to the marginal effect of the interaction term. I present consistent estimators of both marginal and interaction effects in ordered response models. This procedure is general and can easily be extended to other discrete choice models. I ...

CRBRP structural and thermal margin beyond the design base

International Nuclear Information System (INIS)

Strawbridge, L.E.

1979-01-01

Prudent margins beyond the design base have been included in the design of Clinch River Breeder Reactor Plant to further reduce the risk to the public from highly improbable occurrences. These margins include Structural Margin Beyond the Design Base to address the energetics aspects and Thermal Margin Beyond the Design Base to address the longer term thermal and radiological consequences. The assessments that led to the specification of these margins are described, along with the experimental support for those assessments. 8 refs

AUTOMATIZACIÓN DE LA ARQUITECTURA DE COMPONENTES GENÉRICOS USANDO UML

Directory of Open Access Journals (Sweden)

Noel Fuentes Ramírez

2006-04-01

Full Text Available

La arquitectura de componentes genéricos permite chequear la consistencia interna de sus elementos arquitectónicos (componentes y conectores a partir de las relaciones internas en sus respectivas estructuras, que pueden ser de inclusión y transformación. También permite verificar la conexión entre componentes y conectores a partir de las relaciones de transformación entre sus interfaces respectivas. Las ideas que se presentan aquí constituyen una propuesta para la automatización de la descripción de esta arquitectura usando el lenguaje de modelado unificado (UML a partir de la descripción formal de sus diagramas de clases y de secuencia, así como para el chequeo de la consistencia. En este artículo se muestra la aplicación de esta propuesta mediante una extensión de la herramienta Visual Paradigm, por medio de un módulo de software conectable.

Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

Science.gov (United States)

Mercado, Catherine E; Drew, Peter A; Morris, Christopher G; Dziegielewski, Peter T; Mendenhall, William M; Amdur, Robert J

2018-04-16

The significance of positive margin in favorable-stage well-differentiated thyroid cancer is controversial. We report outcomes of positive-margin patients with a matched-pair comparison to a negative-margin group. A total of 25 patients with classic-histology papillary or follicular carcinoma, total thyroidectomy +/- node dissection, stage T1-3N0-1bM0, positive surgical margin at primary site, adjuvant radioactive iodine (I-131), and age older than 18 years were treated between 2003 and 2013. Endpoints were clinical and biochemical (thyroglobulin-only) recurrence-free survival. Matched-pair analysis involved a 1:1 match with negative-margin cases matched for overall stage and I-131 dose. Recurrence-free survival in positive-margin patients was 71% at 10 years. No patient was successfully salvaged with additional treatment. Only 1 patient died of thyroid cancer. Recurrence-free survival at 10 years was worse with a positive (71%) versus negative (90%) margin (P=0.140). Cure with a microscopically positive margin was suboptimal (71%) despite patients having classic-histology papillary and follicular carcinoma, favorable stage, and moderate-dose I-131 therapy.

Learning Convex Inference of Marginals

OpenAIRE

Domke, Justin

2012-01-01

Graphical models trained using maximum likelihood are a common tool for probabilistic inference of marginal distributions. However, this approach suffers difficulties when either the inference process or the model is approximate. In this paper, the inference process is first defined to be the minimization of a convex function, inspired by free energy approximations. Learning is then done directly in terms of the performance of the inference process at univariate marginal prediction. The main ...

Efeito de instruções usando DVD-ROM no desempenho técnico de massoterapia miofascial e sua retenção

OpenAIRE

Luiz Francisco Cachoni

2014-01-01

Contextualização: Existem poucas investigações sobre recursos didáticos modernos para o ensino de habilidades técnicas de massoterapia. Objetivo: Avaliar o efeito de instruções usando filme no formato DVD associado ao ensino tradicional (aula expositiva com demonstração do instrutor em um voluntário), no aprendizado e na retenção de massagem miofascial (MM). Método: Estudo retrospectivo e duplo cego. Uma fisioterapeuta experiente que atuou como professora (cega ao objetivo do estudo) e 60 fis...

Spectrum estimation method based on marginal spectrum

International Nuclear Information System (INIS)

Cai Jianhua; Hu Weiwen; Wang Xianchun

2011-01-01

FFT method can not meet the basic requirements of power spectrum for non-stationary signal and short signal. A new spectrum estimation method based on marginal spectrum from Hilbert-Huang transform (HHT) was proposed. The procession of obtaining marginal spectrum in HHT method was given and the linear property of marginal spectrum was demonstrated. Compared with the FFT method, the physical meaning and the frequency resolution of marginal spectrum were further analyzed. Then the Hilbert spectrum estimation algorithm was discussed in detail, and the simulation results were given at last. The theory and simulation shows that under the condition of short data signal and non-stationary signal, the frequency resolution and estimation precision of HHT method is better than that of FFT method. (authors)

MODELACIÓN NUMÉRICA DE PROCESOS DE ESTERILIZACIÓN TÉRMICA DE ALIMENTOS USANDO VOLUMENES DE CONTROL: APROXIMACIÓN CILÍNDRICA

OpenAIRE

HÉCTOR J. CIRO-VELÁSQUEZ; CARLOS GONZÁLEZ; EDUARD GARCÍA

2009-01-01

Un proceso de esterilización térmica de alimentos fue modelado usando la técnica de diferenciación finita aplicada a volúmenes de control. El modelo de simulación fue desarrollado en coordenadas cilíndricas con un ejemplo de aplicación tomando como referencia un producto cárnico (carne de res). Los resultados de la simulación mostraron que el algoritmo desarrollado es independiente de la red nodal seleccionada, permitiendo cuantificar las curvas de penetración de calor en el punto crítico del...

Thermal margin model for transition core of KSNP

International Nuclear Information System (INIS)

Nahm, Kee Yil; Lim, Jong Seon; Park, Sung Kew; Chun, Chong Kuk; Hwang, Sun Tack

2004-01-01

The PLUS7 fuel was developed with mixing vane grids for KSNP. For the transition core partly loaded with the PLUS7 fuels, the procedure to set up the optimum thermal margin model of the transition core was suggested by introducing AOPM concept into the screening method which determines the limiting assembly. According to the procedure, the optimum thermal margin model of the first transition core was set up by using a part of nuclear data for the first transition and the homogeneous core with PLUS7 fuels. The generic thermal margin model of PLUS7 fuel was generated with the AOPM of 138%. The overpower penalties on the first transition core were calculated to be 1.0 and 0.98 on the limiting assembly and the generic thermal margin model, respectively. It is not usual case to impose the overpower penalty on reload cores. It is considered that the lack of channel flow due to the difference of pressure drop between PLUS7 and STD fuels results in the decrease of DNBR. The AOPM of the first transition core is evaluated to be about 135% by using the optimum generic thermal margin model which involves the generic thermal margin model and the total overpower penalty. The STD fuel is not included among limiting assembly candidates in the second transition core, because they have much lower pin power than PLUS7 fuels. The reduced number of STD fuels near the limiting assembly candidates the flow from the limiting assembly to increase the thermal margin for the second transition core. It is expected that cycle specific overpower penalties increase the thermal margin for the transition core. Using the procedure to set up the optimum thermal margin model makes sure that the enhanced thermal margin of PLUS7 fuel can be sufficiently applied to not only the homogeneous core but also the transition core

Reconstructing Rodinia by Fitting Neoproterozoic Continental Margins

Science.gov (United States)

Stewart, John H.

2009-01-01

Reconstructions of Phanerozoic tectonic plates can be closely constrained by lithologic correlations across conjugate margins by paleontologic information, by correlation of orogenic belts, by paleomagnetic location of continents, and by ocean floor magmatic stripes. In contrast, Proterozoic reconstructions are hindered by the lack of some of these tools or the lack of their precision. To overcome some of these difficulties, this report focuses on a different method of reconstruction, namely the use of the shape of continents to assemble the supercontinent of Rodinia, much like a jigsaw puzzle. Compared to the vast amount of information available for Phanerozoic systems, such a limited approach for Proterozoic rocks, may seem suspect. However, using the assembly of the southern continents (South America, Africa, India, Arabia, Antarctica, and Australia) as an example, a very tight fit of the continents is apparent and illustrates the power of the jigsaw puzzle method. This report focuses on Neoproterozoic rocks, which are shown on two new detailed geologic maps that constitute the backbone of the study. The report also describes the Neoproterozoic, but younger or older rocks are not discussed or not discussed in detail. The Neoproterozoic continents and continental margins are identified based on the distribution of continental-margin sedimentary and magmatic rocks that define the break-up margins of Rodinia. These Neoproterozoic continental exposures, as well as critical Neo- and Meso-Neoproterozoic tectonic features shown on the two new map compilations, are used to reconstruct the Mesoproterozoic supercontinent of Rodinia. This approach differs from the common approach of using fold belts to define structural features deemed important in the Rodinian reconstruction. Fold belts are difficult to date, and many are significantly younger than the time frame considered here (1,200 to 850 Ma). Identifying Neoproterozoic continental margins, which are primarily

Análisis de un sistema de almacenamiento de energía térmica usando cloruro de magnesio hexahidratado

Directory of Open Access Journals (Sweden)

Andrés Felipe Macía

2010-01-01

Full Text Available Se simuló el comportamiento del cloruro de magnesio hexahidratado (MgCl2*6H2O como almacenador de energía térmica, que posee una temperatura de transición de fase de 117ºC; lo que lo convierte en un material con gran potencial en el área de las aplicaciones de mediana temperatura (aplicaciones industriales. Se desarrolló una simulación CFD usando el software FLUENT para describir la fusión/solidificación de la sal hidratada. Se observó el efecto del uso de aletas y las fuerzas boyantes producidas por los efectos gravitacionales.

Margins for treatment planning of proton therapy

International Nuclear Information System (INIS)

Thomas, Simon J

2006-01-01

For protons and other charged particles, the effect of set-up errors on the position of isodoses is considerably less in the direction of the incident beam than it is laterally. Therefore, the margins required between the clinical target volume (CTV) and planning target volume (PTV) can be less in the direction of the incident beam than laterally. Margins have been calculated for a typical head plan and a typical prostate plan, for a single field, a parallel opposed and a four-field arrangement of protons, and compared with margins calculated for photons, assuming identical geometrical uncertainties for each modality. In the head plan, where internal motion was assumed negligible, the CTV-PTV margin reduced from approximately 10 mm to 3 mm in the axial direction for the single field and parallel opposed plans. For a prostate plan, where internal motion cannot be ignored, the corresponding reduction in margin was from 11 mm to 7 mm. The planning organ at risk (PRV) margin in the axial direction reduced from 6 mm to 2 mm for the head plan, and from 7 mm to 4 mm for the prostate plan. No reduction was seen on the other axes, or for any axis of the four-field plans. Owing to the shape of proton dose distributions, there are many clinical cases in which good dose distributions can be obtained with one or two fields. When this is done, it is possible to use smaller PTV and PRV margins. This has the potential to convert untreatable cases, in which the PTV and PRV overlap, into cases with a gap between PTV and PRV of adequate size for treatment planning

Clasificación digital de masas nubosas a partir de imágenes meteorológicas usando algoritmos de aprendizaje de máquina

Directory of Open Access Journals (Sweden)

Salomón Einstein Ramírez-Fernández

2014-01-01

Full Text Available La identificación exacta de nubes precipitantes es una tarea difícil. En el presente trabajo se aplicaron los algoritmos Máquinas de Soporte Vectorial, Árboles de Decisión y Bosques Aleatorios para discriminar entre nubes precipitantes y nubes no precipitantes, a partir de una imagen meteorológica del satélite GOES-13 que cubre el territorio colombiano. El objetivo del trabajo fue evaluar el desempeño de los algoritmos de aprendizaje de máquina (ML, para la clasificación digital de masas nubosas, en términos de la exactitud temática de la clasificación usando como referencia el algoritmo convencional distancia de Mahalanobis. Los resultados muestran que los algoritmos ML proporcionan una clasificación de masas de nubes más exacta que la obtenida por algoritmos convencionales. La mejor exactitud fue obtenida usando Bosques Aleatorios (RF, con una exactitud temática global de 97%. Adicionalmente, la clasificación obtenida con RF fue comparada pixel a pixel con estimaciones de precipitación de la NASA Tropical Rainfall Measurement Mission (TRMM obteniendo una exactitud global del 94%. De acuerdo con este estudio, los algoritmos ML pueden ser usados para mejorar los actuales métodos de identificación de nubes precipitantes.

Margins in breast conserving surgery: The financial cost & potential savings associated with the new margin guidelines.

Science.gov (United States)

Singer, Lauren; Brown, Eric; Lanni, Thomas

2016-08-01

In this study, we compare the indications for re-excision, the findings of additional tumor in the re-excision specimen as they relate to margin status, and costs associated with re-excision based on recent new consensus statements. A retrospective analysis was performed on 462 patients with invasive breast carcinoma who underwent at least one lumpectomy between January 2011 and December 2013. Postoperative data was analyzed based on where additional disease was found, as it relates to the margin status of the initial lumpectomy and the additional direct costs associated with additional procedures. Of the 462 patients sampled, 149 underwent a re-excision surgery (32.2%). Four patients underwent mastectomy as their second operation. In the 40 patients with additional disease found on re-excision, 36 (90.0%) of them had a positive margin on their initial lumpectomy. None of the four mastectomy patients had residual disease. The mean cost of the initial lumpectomy for all 462 patients was $2118.01 plus an additional $1801.92 for those who underwent re-excision. A positive margin was most predictive of finding residual tumor on re-excision as would be expected. Using old criteria only 0.07% (4/61) of patients who had undergone re-excision with a 'clear' margin, had additional tumor found, at a total cost of $106,354.11. Thus, the new consensus guidelines will lead to less overall cost, at no clinical risk to patients while reducing a patient's surgical risk and essentially eliminating delays in adjuvant care. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plasticity margin recovery during annealing after cold deformation

International Nuclear Information System (INIS)

Bogatov, A.A.; Smirnov, S.V.; Kolmogorov, V.L.

1978-01-01

Restoration of the plasticity margin in steel 20 after cold deformation and annealing at 550 - 750 C and soaking for 5 - 300 min was investigated. The conditions of cold deformation under which the metal acquires microdefects unhealed by subsequent annealing were determined. It was established that if the degree of utilization of the plasticity margin is psi < 0.5, the plasticity margin in steel 20 can be completely restored by annealing. A mathematical model of restoration of the plasticity margin by annealing after cold deformation was constructed. A statistical analysis showed good agreement between model and experiment

Reinforcing marginality? Maternal health interventions in rural Nicaragua.

Science.gov (United States)

Kvernflaten, Birgit

2017-06-23

To achieve Millennium Development Goal 5 on maternal health, many countries have focused on marginalized women who lack access to care. Promoting facility-based deliveries to ensure skilled birth attendance and emergency obstetric care has become a main measure for preventing maternal deaths, so women who opt for home births are often considered 'marginal' and in need of targeted intervention. Drawing upon ethnographic data from Nicaragua, this paper critically examines the concept of marginality in the context of official efforts to increase institutional delivery amongst the rural poor, and discusses lack of access to health services among women living in peripheral areas as a process of marginalization. The promotion of facility birth as the new norm, in turn, generates a process of 're-marginalization', whereby public health officials morally disapprove of women who give birth at home, viewing them as non-compliers and a problem to the system. In rural Nicaragua, there is a discrepancy between the public health norm and women's own preferences and desires for home birth. These women live at the margins also in spatial and societal terms, and must relate to a health system they find incapable of providing good, appropriate care. Strong public pressure for institutional delivery makes them feel distressed and pressured. Paradoxically then, the aim of including marginal groups in maternal health programmes engenders resistance to facility birth.

Effect of posterior crown margin placement on gingival health.

Science.gov (United States)

Reitemeier, Bernd; Hänsel, Kristina; Walter, Michael H; Kastner, Christian; Toutenburg, Helge

2002-02-01

The clinical impact of posterior crown margin placement on gingival health has not been thoroughly quantified. This study evaluated the effect of posterior crown margin placement with multivariate analysis. Ten general dentists reviewed 240 patients with 480 metal-ceramic crowns in a prospective clinical trial. The alloy was randomly selected from 2 high gold, 1 low gold, and 1 palladium alloy. Variables were the alloy used, oral hygiene index score before treatment, location of crown margins at baseline, and plaque index and sulcus bleeding index scores recorded for restored and control teeth after 1 year. The effect of crown margin placement on sulcular bleeding and plaque accumulation was analyzed with regression models (Prisk of bleeding at intrasulcular posterior crown margins was approximately twice that at supragingival margins. Poor oral hygiene before treatment and plaque also were associated with sulcular bleeding. Facial sites exhibited a lower probability of sulcular bleeding than lingual surfaces. Type of alloy did not influence sulcular bleeding. In this study, placement of crown margins was one of several parameters that affected gingival health.

Colorado Basin Structure and Rifting, Argentine passive margin

Science.gov (United States)

Autin, Julia; Scheck-Wenderoth, Magdalena; Loegering, Markus; Anka, Zahie; Vallejo, Eduardo; Rodriguez, Jorge; Marchal, Denis; Reichert, Christian; di Primio, Rolando

2010-05-01

The Argentine margin presents a strong segmentation with considerable strike-slip movements along the fracture zones. We focus on the volcanic segment (between the Salado and Colorado transfer zones), which is characterized by seaward dipping reflectors (SDR) all along the ocean-continent transition [e.g. Franke et al., 2006; Gladczenko et al., 1997; Hinz et al., 1999]. The segment is structured by E-W trending basins, which differs from the South African margin basins and cannot be explained by classical models of rifting. Thus the study of the relationship between the basins and the Argentine margin itself will allow the understanding of their contemporary development. Moreover the comparison of the conjugate margins suggests a particular evolution of rifting and break-up. We firstly focus on the Colorado Basin, which is thought to be the conjugate of the well studied Orange Basin [Hirsch et al., 2009] at the South African margin [e.g. Franke et al., 2006]. This work presents results of a combined approach using seismic interpretation and structural, isostatic and thermal modelling highlighting the structure of the crust. The seismic interpretation shows two rift-related discordances: one intra syn-rift and the break-up unconformity. The overlying sediments of the sag phase are less deformed (no sedimentary wedges) and accumulated before the generation of oceanic crust. The axis of the Colorado Basin trends E-W in the western part, where the deepest pre-rift series are preserved. In contrast, the basin axis turns to a NW-SE direction in its eastern part, where mainly post-rift sediments accumulated. The most distal part reaches the margin slope and opens into the oceanic basin. The general basin direction is almost orthogonal to the present-day margin trend. The most frequent hypothesis explaining this geometry is that the Colorado Basin is an aborted rift resulting from a previous RRR triple junction [e.g. Franke et al., 2002]. The structural interpretation

The Seismicity of Two Hyperextended Margins

Science.gov (United States)

Redfield, Tim; Terje Osmundsen, Per

2013-04-01

A seismic belt marks the outermost edge of Scandinavia's proximal margin, inboard of and roughly parallel to the Taper Break. A similar near- to onshore seismic belt runs along its inner edge, roughly parallel to and outboard of the asymmetric, seaward-facing escarpment. The belts converge at both the northern and southern ends of Scandinavia, where crustal taper is sharp and the proximal margin is narrow. Very few seismic events have been recorded on the intervening, gently-tapering Trøndelag Platform. Norway's distribution of seismicity is systematically ordered with respect to 1) the structural templates of high-beta extension that shaped the thinning gradient during Late Jurassic or Early Cretaceous time, and 2) the topographically resurgent Cretaceous-Cenozoic "accommodation phase" family of escarpments that approximate the innermost limit of crustal thinning [See Redfield and Osmundsen (2012) for diagrams, definitions, discussion, and supporting citations.] Landwards from the belt of earthquake epicenters that mark the Taper Break the crust consistently thickens, and large fault arrays tend to sole out at mid crustal levels. Towards the sea the crystalline continental crust is hyperextended, pervasively faulted, and generally very thin. Also, faulting and serpentinization may have affected the uppermost parts of the distal margin's lithospheric mantle. Such contrasting structural conditions may generate a contrasting stiffness: for a given stress, more strain can be accommodated in the distal margin than in the less faulted proximal margin. By way of comparison, inboard of the Taper Break on the gently-tapered Trøndelag Platform, faulting was not penetrative. There, similar structural conditions prevail and proximal margin seismicity is negligible. Because stress concentration can occur where material properties undergo significant contrast, the necking zone may constitute a natural localization point for post-thinning phase earthquakes. In Scandinavia

The Marginal Source of Finance

OpenAIRE

Lindhe, Tobias

2002-01-01

This paper addresses the ongoingdebate on which view of equity, traditional or new, that best describes firm behavior. According to the traditional view, the marginal source of finance is new equity, whereas under to the new view, marginal financing comes from retained earnings. In the theoretical part, we set up a model where the firm faces a cost of adjusting the dividend level because of an aggravated free cash flow problem. The existence of such a cost - which has been used in arguing the...

Estructura y diversidad genética en vacas Holstein de Antioquia usando un polimorfismo del gen bGH

Directory of Open Access Journals (Sweden)

Juan Rincon F.

2013-03-01

Full Text Available Objetivo. Determinar las frecuencias alélicas y genotípicas del polimorfismo del intrón 3 del gen bGH y estimar algunos parámetros de estructura poblacional en ganado Holstein. Materiales y métodos. El estudio se realizó con 1366 vacas Holstein en 120 hatos de 11 municipios del departamento de Antioquia. Se extrajo DNA por el método de Salting out y la genotipificación se realizó usando la técnica de PCR-RFLPs. La diversidad genética se determinó mediante la comparación de las heterocigosidades, El equilibrio de Hardy-Weinberg (HW y la diferenciación genética entre las poblaciones se realizó usando el software Arlequín 2.0 Las frecuencias alélicas y genotípicas se evaluaron mediante el paquete estadístico SAS®. Resultados. Las frecuencias genotípicas encontradas fueron 0.764 (+/+, 0.223 (+/- y 0.013 (-/- y las frecuencias alélicas 0.876 (+ y 0.124 (-. No se encontraron desviaciones del Equilibrio de Hardy Weinberg en ninguna de las subpoblaciones. La diversidad genética determinada mediante la comparación de las heterocigosidades fue relativamente baja entre poblaciones pero al interior de estas no. El valor de FST de toda la población fue de 0.0068 y significativo (p<0.05, algunos FST pareados también lo fueron, tomando valores desde 0.0 a 0.13. Los estadísticos FIT y FIS no fueron significativos. Conclusiones. El gen bGH es un candidato interesante para evaluar características de importancia económica ya que no parece haber sido sometido a selección directa, presenta una variabilidad media en las poblaciones, observándose diferenciación genética significativa entre distintos municipios, producto de los diferentes sistemas de producción y acceso a las biotecnologías.

On probabilistically defined margins in radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Papiez, Lech; Langer, Mark [Department of Radiation Oncology, Indiana University, Indianapolis, IN (United States)

2006-08-21

Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem

On probabilistically defined margins in radiation therapy

International Nuclear Information System (INIS)

Papiez, Lech; Langer, Mark

2006-01-01

Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem

The homogeneous marginal utility of income assumption

NARCIS (Netherlands)

Demuynck, T.

2015-01-01

We develop a test to verify if every agent from a population of heterogeneous consumers has the same marginal utility of income function. This homogeneous marginal utility of income assumption is often (implicitly) used in applied demand studies because it has nice aggregation properties and

Implementación de un mantenimiento basado en la condición usando modelado y simulación: caso de estudio de un motor sin-crónico de imanes permanentes

Directory of Open Access Journals (Sweden)

Jabid Quiroga Méndez

2011-05-01

Full Text Available Este artículo introduce la arquitectura de un CBM (mantenimiento basado en la condición en una aplicación eléctrica. La detección de fallas de manera oportuna y eficiente constituye uno de los retos más importantes asociados al CBM y el enfoque basado en modelos en el medio para conseguirlo. Un caso de estudio en un motor sincrónico de imanes permanentes (PMSM es ejecutado para ilustrar cómo el modelado es utilizado en la implementación de un CBM. El monitoreo fue implementado en tiempo real usando Matlab® y dSpace®. Se emplea como indicadora de falla la diferencia entre los valores de la componente secuencial negativa para las corrientes predichas usando una red neuronal multicapa y la corriente obtenida del motor. Resultados experimentales demostraron la efectividad del modelo propuesto en la detección de la falla de cortocircuito en el estator en distintos niveles de severidad y carga, obteniendo una confiabilidad en la detección mayor al 95%.

Evaluation of margining algorithms in commercial treatment planning systems

International Nuclear Information System (INIS)

Pooler, Alistair M.; Mayles, Helen M.; Naismith, Olivia F.; Sage, John P.; Dearnaley, David P.

2008-01-01

Introduction: During commissioning of the Pinnacle (Philips) treatment planning system (TPS) the margining algorithm was investigated and was found to produce larger PTVs than Plato (Nucletron) for identical GTVs. Subsequent comparison of PTV volumes resulting from the QA outlining exercise for the CHHIP (Conventional or Hypofractionated High Dose IMRT for Prostate Ca.) trial confirmed that there were differences in TPS's margining algorithms. Margining and the clinical impact of the different PTVs in seven different planning and virtual simulation systems (Pinnacle, Plato, Prosoma (MedCom), Eclipse (7.3 and 7.5) (Varian), MasterPlan (Nucletron), Xio (CMS) and Advantage Windows (AW) (GE)) is investigated, and a simple test for 3D margining consistency is proposed. Methods: Using each TPS, two different sets of prostate GTVs on 2.5 mm and 5 mm slices were margined according to the CHHIP protocol to produce PTV3 (prostate + 5 mm/0 mm post), PTV2 (PTV3 + 5 mm) and PTV1 (prostate and seminal vesicles + 10 mm). GTVs and PTVs were imported into Pinnacle for volume calculation. DVHs for 5 mm slice plans, created using the smallest PTVs, were recalculated on the largest PTV dataset and vice versa. Since adding a margin of 50 mm to a structure should give the same result as adding five margins of 10 mm, this was tested for each TPS (consistency test) using an octahedron as the GTV and CT datasets with 2.5 mm and 5 mm slices. Results: The CHHIP PTV3 and PTV1 volumes had a standard deviation, across the seven systems, of 5% and PTV2 (margined twice) 9%, on the 5 mm slices. For 2.5 mm slices the standard deviations were 4% and 6%. The ratio of the Pinnacle and the Eclipse 7.3 PTV2 volumes was 1.25. Rectal doses were significantly increased when encompassing Pinnacle PTVs (V 50 42.8%), compared to Eclipse 7.3 PTVs (V 50 = 36.4%). Conversely, fields that adequately treated an Eclipse 7.3 PTV2 were inadequate for a Pinnacle PTV2. AW and Plato PTV volumes were the most consistent

Large margin image set representation and classification

KAUST Repository

Wang, Jim Jing-Yan; Alzahrani, Majed A.; Gao, Xin

2014-01-01

In this paper, we propose a novel image set representation and classification method by maximizing the margin of image sets. The margin of an image set is defined as the difference of the distance to its nearest image set from different classes and the distance to its nearest image set of the same class. By modeling the image sets by using both their image samples and their affine hull models, and maximizing the margins of the images sets, the image set representation parameter learning problem is formulated as an minimization problem, which is further optimized by an expectation - maximization (EM) strategy with accelerated proximal gradient (APG) optimization in an iterative algorithm. To classify a given test image set, we assign it to the class which could provide the largest margin. Experiments on two applications of video-sequence-based face recognition demonstrate that the proposed method significantly outperforms state-of-the-art image set classification methods in terms of both effectiveness and efficiency.

Large margin image set representation and classification

KAUST Repository

Wang, Jim Jing-Yan

2014-07-06

In this paper, we propose a novel image set representation and classification method by maximizing the margin of image sets. The margin of an image set is defined as the difference of the distance to its nearest image set from different classes and the distance to its nearest image set of the same class. By modeling the image sets by using both their image samples and their affine hull models, and maximizing the margins of the images sets, the image set representation parameter learning problem is formulated as an minimization problem, which is further optimized by an expectation - maximization (EM) strategy with accelerated proximal gradient (APG) optimization in an iterative algorithm. To classify a given test image set, we assign it to the class which could provide the largest margin. Experiments on two applications of video-sequence-based face recognition demonstrate that the proposed method significantly outperforms state-of-the-art image set classification methods in terms of both effectiveness and efficiency.

Single-Center Experience Using Marginal Liver Grafts in Korea.

Science.gov (United States)

Park, P-J; Yu, Y-D; Yoon, Y-I; Kim, S-R; Kim, D-S

2018-05-01

Liver transplantation (LT) is an established therapeutic modality for patients with end-stage liver disease. The use of marginal donors has become more common worldwide due to the sharp increase in recipients, with a consequent shortage of suitable organs. We analyzed our single-center experience over the last 8 years in LT to evaluate the outcomes of using so-called "marginal donors." We retrospectively analyzed the database of all LTs performed at our institution from 2009 to 2017. Only patients undergoing deceased-donor LTs were analyzed. Marginal grafts were defined as livers from donors >60 years of age, livers from donors with serum sodium levels >155 mEq, graft steatosis >30%, livers with cold ischemia time ≥12 hours, livers from donors who were hepatitis B or C virus positive, livers recovered from donation after cardiac death, and livers split between 2 recipients. Patients receiving marginal grafts (marginal group) were compared with patients receiving standard grafts (standard group). A total of 106 patients underwent deceased-donor LT. There were 55 patients in the standard group and 51 patients in the marginal group. There were no significant differences in terms of age, sex, Model for End-Stage Liver Disease score, underlying liver disease, presence of hepatocellular carcinoma, and hospital stay between the 2 groups. Although the incidence of acute cellular rejection, cytomegalovirus infection, and postoperative complications was similar between the 2 groups, the incidence of early allograft dysfunction was higher in the marginal group. With a median follow-up of 26 months, the 1-, 3-, and 5-year overall and graft (death-censored) survivals in the marginal group were 85.5%, 75%, and 69.2% and 85.9%, 83.6%, and 77.2%, respectively. Patient overall survival and graft survival (death-censored) were significantly lower in the marginal group (P = .023 and P = .048, respectively). On multivariate analysis, receiving a marginal graft (hazard ratio [HR

Marginal-cost pricing for Hydro-Quebec residential customers

International Nuclear Information System (INIS)

Paquin, C.

1994-02-01

An option available to governments and to utilities such as Hydro-Quebec for responding to objectives of energy efficiency is the adoption of marginal cost pricing. Compared to currently used price structures, marginal cost pricing will allow improvement of price signals and assure an optimal utilization of the resource. That type of pricing could be economically beneficial but may not be desirable from the point of view of revenue distribution. Taking account of Hydro-Quebec's cost structure, pure marginal cost pricing would generate an income that would be strongly contested on equity grounds. For example, it would raise prices 60% for residential customers. Faced with this possibility, an analysis is presented of the impact of a peak-offpeak pricing (or pure marginal cost pricing) on Hydro-Quebec's residential customer energy bills. The marginal costs of Hydro-Quebec are calculated by the method of Bernard and Chatel (1985) and analysis of the results is based on Friedman and Weare (1993). A sample of 28,417 residential customers from a 1989 Hydro-Quebec survey is used in the study. Two scenarios are analyzed; the first allowing comparison of the energy bill only on the basis of marginal costs and of average costs, and the second allowing comparison of the impact of marginal cost pricing on the total bill. In the first scenario, the impact translates into a 31% increase in energy bills for the entire customer class considered; in addition, this impact is inversely proportional to the revenue class. In the second scenario, the increase is 24%. 33 refs., 10 figs., 53 tabs

How to make offshore marginal fields work for everyone

International Nuclear Information System (INIS)

Blandford, P.R.

1995-01-01

Marginal fields make positive impact on certain oil and gas companies' financial performances. These developments are integrated into the operator's operational and philosophical mindset, so that they optimize return and establish a reasonable reserve base for the company. Having a portfolio of marginal field developments is definitely a part of the offshore business, and oil field suppliers and subcontractors will continue to develop technology and methods to ensure the fields are exploited. It goes without saying that the continued production of marginal fields helps a lot of consumers and the companies that make up the energy chain that gets it to them. There are marginal fields all over the world and the market can only grow as more and more of the resources decline and industrialization expands demand. The projections for 2020 state that fossil fuels will remain the major supply link to dependable and affordable energy, particularly as additional oil and gas infrastructures are built and installed. Likened to the commodity, oil and gas companies and the energy industry have slowly evolved to the point where they are making a difference for people worldwide. As long as there is product to produce, most companies and consumers do not really care what type of reservoir started it all. More often then not, it probably started out as a marginal prospect. The paper discusses the energy picture today, marginal field update, offshore marginal field geography, and independent and marginal field developments

Exploring the Subtleties of Inverse Probability Weighting and Marginal Structural Models.

Science.gov (United States)

Breskin, Alexander; Cole, Stephen R; Westreich, Daniel

2018-05-01

Since being introduced to epidemiology in 2000, marginal structural models have become a commonly used method for causal inference in a wide range of epidemiologic settings. In this brief report, we aim to explore three subtleties of marginal structural models. First, we distinguish marginal structural models from the inverse probability weighting estimator, and we emphasize that marginal structural models are not only for longitudinal exposures. Second, we explore the meaning of the word "marginal" in "marginal structural model." Finally, we show that the specification of a marginal structural model can have important implications for the interpretation of its parameters. Each of these concepts have important implications for the use and understanding of marginal structural models, and thus providing detailed explanations of them may lead to better practices for the field of epidemiology.

Values and marginal preferences in international business

NARCIS (Netherlands)

Maseland, Robbert; van Hoorn, Andre

2010-01-01

In a recent paper in this journal, Maseland and van Hoorn argued that values surveys tend to conflate values and marginal preferences. This assertion has been challenged by Brewer and Venaik, who claim that the wording of most survey items does not suggest that these elicit marginal preferences.

Recent progress in Pacific-Asian Marginal Seas (PAMS) studies

Science.gov (United States)

Matsuno, Takeshi; Hirose, Naoki; Zhang, Jing; Cho, Yang-Ki; Chen, Dake; Yuan, Dongliang; Hung, Chin-Chang; Jan, Sen

2017-07-01

Marginal seas which represent the buffer zones between land and the pelagic ocean are being increasingly influenced by human activity. The role of the marginal seas is important for many reasons, among which are biological resources and climate change. In East Asia, we have marginal seas between the Asian Continent and the Pacific Ocean, where various countries and areas form complicated territories and EEZ. To understand the marine environment of marginal seas, international cooperative scientific activities are necessary, and it is essential to share the latest information and knowledge.

The stability margin on EAST tokamak

International Nuclear Information System (INIS)

Jin-Ping, Qian; Bao-Nian, Wan; Biao, Shen; Bing-Jia, Xiao; Walker, M.L.; Humphreys, D.A.

2009-01-01

The experimental advanced superconducting tokamak (EAST) is the first full superconducting tokamak with a D-shaped cross-sectional plasma presently in operation. Its poloidal coils are relatively far from the plasma due to the necessary thermal isolation from the superconducting magnets, which leads to relatively weaker coupling between plasma and poloidal field. This may cause more difficulties in controlling the vertical instability by using the poloidal coils. The measured growth rates of vertical stability are compared with theoretical calculations, based on a rigid plasma model. Poloidal beta and internal inductance are varied to investigate their effects on the stability margin by changing the values of parameters α n and γ n (Howl et al 1992 Phys. Fluids B 4 1724), with plasma shape fixed to be a configuration with k = 1.9 and δ = 0.5. A number of ways of studying the stability margin are investigated. Among them, changing the values of parameters κ and l i is shown to be the most effective way to increase the stability margin. Finally, a guideline of stability margin M s (κ, l i , A) to a new discharge scenario showing whether plasmas can be stabilized is also presented in this paper

Fedme og risiko for marginal parodontitis

DEFF Research Database (Denmark)

Kongstad, Johanne; Keller, Amélie Cléo; Rohde, Jeanett Friis

2017-01-01

Oversigtsartiklen, der er af narrativ karakter, beskriver sammenhængen mellem overvægt/ fedme og marginal parodontitis. Artiklen er baseret på et udvalg af nyere engelsksproget litteratur og motiveres af den øgede forekomst af overvægtige og fede i befolkningen. Desuden er det afgørende, at tandl......Oversigtsartiklen, der er af narrativ karakter, beskriver sammenhængen mellem overvægt/ fedme og marginal parodontitis. Artiklen er baseret på et udvalg af nyere engelsksproget litteratur og motiveres af den øgede forekomst af overvægtige og fede i befolkningen. Desuden er det afgørende......, at tandlæger forholder sig kritisk til systemiske tilstandes mulige konsekvens for udvikling, forværring og behandling af marginal parodontitis. Der nævnes forskellige mål for fedme, hvor body mass index (BMI) og taljeomkreds er de mest anvendte. Problematikken vedrørende tidligere studiers anvendelse af...... forskellige kriterier for marginal parodontitis berøres. Litteraturgennemgangen tager udgangspunkt i de biologiske mekanismer, der udløses i fedtvæv ved overvægt/fedme og medfører en kronisk inflammatorisk tilstand med frigivelse af bl.a. adipokiner. Epidemiologiske tværsnitsog longitudinelle studier af...

Refining prices and margins in 1998

International Nuclear Information System (INIS)

Favennec, J.P.; Baudoin, C.

1999-01-01

Despite a business environment that was globally mediocre due primarily to the Asian crisis and to a mild winter in the northern hemisphere, the signs of improvement noted in the refining activity in 1996 were borne out in 1997. But the situation is not yet satisfactory in this sector: the low return on invested capital and the financing of environmental protection expenditure are giving cause for concern. In 1998, the drop in crude oil prices and the concomitant fall in petroleum product prices was ultimately rather favorable to margins. Two elements tended to put a damper on this relative optimism. First of all, margins continue to be extremely volatile and, secondly, the worsening of the economic and financial crisis observed during the summer made for a sharp decline in margins in all geographic regions, especially Asia

Variantes del problema del cartero mixto que se pueden resolver usando programación lineal

Directory of Open Access Journals (Sweden)

Francisco Javier Zaragoza Martínez

2012-07-01

Full Text Available Dada una gráfica mixta y conexa con costos en sus aristas y arcos, el problema del cartero mixto consiste en encontrar un circuito cerrado de la gráfica mixta que recorra sus aristas y arcos a costo mínimo. Se sabe que este problema es NP-duro. Sin embargo, bajo ciertas condiciones adicionales, el problema se puede resolver en tiempo polinomial usando programación lineal, en otras palabras, los poliedros correspondientes son enteros. Algunas de estas condiciones son: la gráfica mixta es serie paralelo o la gráfica mixta tiene grado total par en todos sus vértices. Además, mostramos que si agregamos la restricción adicional de que cada arista se recorra exactamente una vez entonces el problema se puede resolver en tiempo polinomial si el conjunto de arcos forma un bosque. Palabras clave: Gráfica mixta, problema de cartero, programación lineal. Mathematics Subject Classification: 05C45, 90C35.

Realistic respiratory motion margins for external beam partial breast irradiation

Energy Technology Data Exchange (ETDEWEB)

Conroy, Leigh; Quirk, Sarah [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta T2N 4N2 (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Smith, Wendy L., E-mail: wendy.smith@albertahealthservices.ca [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta T2N 4N2 (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Department of Oncology, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

2015-09-15

Purpose: Respiratory margins for partial breast irradiation (PBI) have been largely based on geometric observations, which may overestimate the margin required for dosimetric coverage. In this study, dosimetric population-based respiratory margins and margin formulas for external beam partial breast irradiation are determined. Methods: Volunteer respiratory data and anterior–posterior (AP) dose profiles from clinical treatment plans of 28 3D conformal radiotherapy (3DCRT) PBI patient plans were used to determine population-based respiratory margins. The peak-to-peak amplitudes (A) of realistic respiratory motion data from healthy volunteers were scaled from A = 1 to 10 mm to create respiratory motion probability density functions. Dose profiles were convolved with the respiratory probability density functions to produce blurred dose profiles accounting for respiratory motion. The required margins were found by measuring the distance between the simulated treatment and original dose profiles at the 95% isodose level. Results: The symmetric dosimetric respiratory margins to cover 90%, 95%, and 100% of the simulated treatment population were 1.5, 2, and 4 mm, respectively. With patient set up at end exhale, the required margins were larger in the anterior direction than the posterior. For respiratory amplitudes less than 5 mm, the population-based margins can be expressed as a fraction of the extent of respiratory motion. The derived formulas in the anterior/posterior directions for 90%, 95%, and 100% simulated population coverage were 0.45A/0.25A, 0.50A/0.30A, and 0.70A/0.40A. The differences in formulas for different population coverage criteria demonstrate that respiratory trace shape and baseline drift characteristics affect individual respiratory margins even for the same average peak-to-peak amplitude. Conclusions: A methodology for determining population-based respiratory margins using real respiratory motion patterns and dose profiles in the AP direction was

Realistic respiratory motion margins for external beam partial breast irradiation

International Nuclear Information System (INIS)

Conroy, Leigh; Quirk, Sarah; Smith, Wendy L.

2015-01-01

Purpose: Respiratory margins for partial breast irradiation (PBI) have been largely based on geometric observations, which may overestimate the margin required for dosimetric coverage. In this study, dosimetric population-based respiratory margins and margin formulas for external beam partial breast irradiation are determined. Methods: Volunteer respiratory data and anterior–posterior (AP) dose profiles from clinical treatment plans of 28 3D conformal radiotherapy (3DCRT) PBI patient plans were used to determine population-based respiratory margins. The peak-to-peak amplitudes (A) of realistic respiratory motion data from healthy volunteers were scaled from A = 1 to 10 mm to create respiratory motion probability density functions. Dose profiles were convolved with the respiratory probability density functions to produce blurred dose profiles accounting for respiratory motion. The required margins were found by measuring the distance between the simulated treatment and original dose profiles at the 95% isodose level. Results: The symmetric dosimetric respiratory margins to cover 90%, 95%, and 100% of the simulated treatment population were 1.5, 2, and 4 mm, respectively. With patient set up at end exhale, the required margins were larger in the anterior direction than the posterior. For respiratory amplitudes less than 5 mm, the population-based margins can be expressed as a fraction of the extent of respiratory motion. The derived formulas in the anterior/posterior directions for 90%, 95%, and 100% simulated population coverage were 0.45A/0.25A, 0.50A/0.30A, and 0.70A/0.40A. The differences in formulas for different population coverage criteria demonstrate that respiratory trace shape and baseline drift characteristics affect individual respiratory margins even for the same average peak-to-peak amplitude. Conclusions: A methodology for determining population-based respiratory margins using real respiratory motion patterns and dose profiles in the AP direction was

17 CFR 41.47 - Withdrawal of margin.

Science.gov (United States)

2010-04-01

... PRODUCTS Customer Accounts and Margin Requirements § 41.47 Withdrawal of margin. (a) By the customer... positions in the account under this Regulation (Subpart E, §§ 41.42 through 41.49). (b) By the security...) Interest charged on credit maintained in the account; (3) Communication or shipping charges with respect to...

Double-sided Moral Hazard and Margin-based Royalty

OpenAIRE

NARIU, Tatsuhiko; UEDA, Kaoru; LEE, DongJoon

2009-01-01

This paper analyzes royalty modes in the franchise arrangements of convenience stores under double-sided moral hazard. In Japan, the majority of franchisors charge margin-based royalties based on net margins rather than sales-based royalties based on sales. We show that the franchisor can attain the first-best outcome by adopting margin-based royalties under double-sided moral hazard. We consider a case where a franchisee sells two kinds of goods; one is shipped from its franchisor and the ot...

Extração do óleo de manjericão usando fluido supercrítico: analise experimental e matemática

Directory of Open Access Journals (Sweden)

Nídia Alves de Barros

2014-01-01

Full Text Available O óleo essencial de manjericão (Ocimum basilicum L. é valorizado no mercado internacional e amplamente usado nas indústrias de condimentos, cosméticos e medicinais. Entre todos os processos que podem ser aplicados na obtenção do óleo, a extração usando fluido supercrítico (EFS pode ser um método seletivo e eficiente, dependendo das condições operacionais, como temperatura e pressão, que precisam ser otimizadas. O objetivo deste estudo foi comparar a eficiência da extração supercrítica, utilizando planejamento experimental, na extração do óleo de manjericão com os métodos convencionais (hidrodestilação e soxhlet. Para a realização da parte experimental, foi utilizado dióxido de carbono como solvente para a EFS e hexano, para aplicação no soxhlet. Foi realizado um delineamento central composto rotacional (DCCR, aplicando três pressões (100, 200 e 300 bar e três temperaturas (30, 40 e 50ºC. Através da hidrodestilação, obteve-se o menor rendimento (0,26%, usando o Soxhlet, o rendimento foi de 2,39% sendo superior, comparado á EFS, que foi de 0,43%. O DCCR mostrou que, para otimizar o processo, é necessário aumentar a pressão e a temperatura para o alcance de maiores rendimentos. Foi possível constatar que o modelo matemático representou bem o processo de extração, propiciando o "scale-up" deste.

Desarrollo de herramienta de gestión de proyectos RUP usando metodologías Scrum + XP : gestión del proyecto y requisitos

OpenAIRE

Molina Romero, Javier; Quishpi Betún, Luis

2016-01-01

Una de las principales causas por las que los proyectos de desarrollo software fracasan es la ausencia de metodología en su desarrollo. La motivación que hay detrás de este proyecto es el desarrollo de una aplicación web usando la metodología Rational Unified Process (RUP) y aprender, en una situación real, cómo desarrollar utilizando las metodologías Scrum + XP. El principal objetivo de este proyecto es el seguimiento y documentación de una aplicación web para gestionar proyectos mediant...

Modelos de pérdida de masa de acero por corrosión atmosférica en Colombia usando inteligencia computacional

Directory of Open Access Journals (Sweden)

Esteban Velilla

2009-01-01

Full Text Available Con el fin de clasificar la corrosividad de las diferentes atmósferas colombianas, como parte de un proyecto de investigación extenso [1], se expusieron placas de acero al carbono en 21 estaciones distribuidas a lo largo de la infraestructura eléctrica del país (líneas de transmisión y subestaciones. En estas estaciones se midieron entre otros, el tiempo de humectación y la deposición de sulfatos y cloruros durante 12 meses; además, bimensualmente se tomaban placas de acero para medir en laboratorio la pérdida de masa sufrida por estas durante el tiempo de exposición. La clasificación de las 21 estaciones se hizo en 4 grupos, considerando: el tiempo de humectación, contenidos de cloruros y sulfatos, la altura sobre el nivel del mar y el tiempo de exposición de las placas; variables consideradas linealmente independientes según la técnica de descomposición en valores singulares (SVD realizada. El criterio utilizado para la clasificación fue el de similitud de las variables utilizando la norma Euclidiana considerada en la red neuronal no supervisada tipo Kohonen. Adicionalmente, se implementaron modelos para la pérdida de masa del acero para cada uno de los grupos usando redes neuronales (RN tipo Feed-Forward, definiéndose como entradas las variables antes mencionadas y como única salida la pérdida de masa. Complementariamente se presenta una comparación entre el modelo de RN para el grupo 1, con otros modelos obtenidos usando Algoritmos Genéticos (AG y el método Simplex.

Time Safety Margin: Theory and Practice

Science.gov (United States)

2016-09-01

Air Education and Training Command Handbook 99-107, T-38 Road to Wings, Randolph Air Force Base, Texas, July 2013. 65 This page was intentionally left...412TW-TIH-16-01 TIME SAFETY MARGIN: THEORY AND PRACTICE WILLIAM R. GRAY, III Chief Test Pilot USAF Test Pilot School SEPTEMBER 2016... Safety Margin: The01y and Practice) was submitted by the Commander, 4 I 2th Test Wing, Edwards AFB, Ca lifornia 93524-6843. Foreign announcement and

Benefit–cost analysis of non-marginal climate and energy projects

International Nuclear Information System (INIS)

Dietz, Simon; Hepburn, Cameron

2013-01-01

Conventional benefit–cost analysis incorporates the normally reasonable assumption that the policy or project under examination is marginal. Among the assumptions this entails is that the policy or project is small, so the underlying growth rate of the economy does not change. However, this assumption may be inappropriate in some important circumstances, including in climate-change and energy policy. One example is global targets for carbon emissions, while another is a large renewable energy project in a small economy, such as a hydropower dam. This paper develops some theory on the evaluation of non-marginal projects, with empirical applications to climate change and energy. We examine the conditions under which evaluation of a non-marginal project using marginal methods may be wrong, and in our empirical examples we show that both qualitative and large quantitative errors are plausible. - Highlights: • This paper develops the theory of the evaluation of non-marginal projects. • It also includes empirical applications to climate change and energy. • We show when evaluation of a non-marginal project using marginal methods is wrong

30 CFR 204.3 - What alternatives are available for marginal properties?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What alternatives are available for marginal... MINERALS REVENUE MANAGEMENT ALTERNATIVES FOR MARGINAL PROPERTIES General Provisions § 204.3 What alternatives are available for marginal properties? If you have production from a marginal property, MMS and...

Margination of Stiffened Red Blood Cells Regulated By Vessel Geometry.

Science.gov (United States)

Chen, Yuanyuan; Li, Donghai; Li, Yongjian; Wan, Jiandi; Li, Jiang; Chen, Haosheng

2017-11-10

Margination of stiffened red blood cells has been implicated in many vascular diseases. Here, we report the margination of stiffened RBCs in vivo, and reveal the crucial role of the vessel geometry in the margination by calculations when the blood is seen as viscoelastic fluid. The vessel-geometry-regulated margination is then confirmed by in vitro experiments in microfluidic devices, and it establishes new insights to cell sorting technology and artificial blood vessel fabrication.

Criticality safety margins for mixtures of fissionable materials

International Nuclear Information System (INIS)

Williamson, T.G.; Mincey, J.F.

1992-01-01

In the determination of criticality safety margins, approximations for combinations of fissile and fissionable isotopes are sometimes used that go by names such as the rule of fractions or equivalency relations. Use of the rule of fractions to ensure criticality safety margins was discussed in an earlier paper. The purpose of this paper is to correct errors and to clarify some of the implications. Deviations of safety margins from those calculated by the rule of fractions are still noted; however, the deviations are less severe. Caution in applying such rules is still urged. In general, these approximations are based on American National Standard ANSI/ANS-8.15, Sec. 5.2. This section allows that ratios of material masses to their limits may be summed for fissile nuclides in aqueous solutions. It also allows the addition of nonfissile nuclides if an aqueous moderator is present and addresses the effects of infinite water or equivalent reflector. Water-reflected binary combinations of aqueous solutions of fissile materials, as well as binary combinations of fissile and fissionable metals, were considered. Some combinations were shown to significantly decrease the margin of subcriticality compared to the single-unit margins. In this study, it is confirmed that some combinations of metal units in an optimum geometry may significantly decrease the margin of subcriticality. For some combinations of aqueous solutions of fissile materials, the margin of subcriticality may also be reduced by very small amounts. The conclusion of Ref. 1 that analysts should be careful in applying equivalency relations for combining materials remains valid and sound advice. The ANSI/ANS standard, which allows the use of ratios of masses to their limits, applies to aqueous, fully water-reflected, single-unit solutions. Extensions to other situations should be considered with extreme care

Implementação da Técnica de Dessorção Térmica Programada (TPD) usando Espectrometria de Massa Quadrupolo

OpenAIRE

Barreto, Ana Marta Fortunato

2011-01-01

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do Grau de Mestre em Engenharia Física O projecto “Implementação da Técnica de Dessorção Térmica Programada (TPD) usando Espectrometria de Massa Quadrupolo”, apresentado nesta Dissertação de Mestrado em Engenharia Física, surgiu como uma proposta de requalificação ao aparelho de análise de superfícies Multitécnica. A dessorção térmica é o fenómeno que permite a separação física de ...

Evaluation of motion management strategies based on required margins

International Nuclear Information System (INIS)

Sawkey, D; Svatos, M; Zankowski, C

2012-01-01

Strategies for delivering radiation to a moving lesion each require a margin to compensate for uncertainties in treatment. These motion margins have been determined here by separating the total uncertainty into components. Probability density functions for the individual sources of uncertainty were calculated for ten motion traces obtained from the literature. Motion margins required to compensate for the center of mass motion of the clinical treatment volume were found by convolving the individual sources of uncertainty. For measurements of position at a frequency of 33 Hz, system latency was the dominant source of positional uncertainty. Averaged over the ten motion traces, the motion margin for tracking with a latency of 200 ms was 4.6 mm. Gating with a duty cycle of 33% required a mean motion margin of 3.2–3.4 mm, and tracking with a latency of 100 ms required a motion margin of 3.1 mm. Feasible reductions in the effects of the sources of uncertainty, for example by using a simple prediction algorithm to anticipate the lesion position at the end of the latency period, resulted in a mean motion margin of 1.7 mm for tracking with a latency of 100 ms, 2.4 mm for tracking with a latency of 200 ms, and 2.1–2.2 mm for the gating strategies with duty cycles of 33%. A crossover tracking latency of 150 ms was found, below which tracking strategies could take advantage of narrower motion margins than gating strategies. The methods described here provide a means to guide selection of a motion management strategy for a given patient. (paper)

Sustainable food production in marginal lands—Case of GDLA member countries

Directory of Open Access Journals (Sweden)

Shabbir A. Shahid

2013-06-01

Full Text Available Sustainable food production in the changing climate and dwindling water resources in the Global Dry Land Alliance (GDLA member countries is a real challenge, especially when considering marginal lands in dryland systems. The definition of marginal land is very vague and defined from different perspectives (pragmatism about marginal lands. Dryland itself indicates "marginality" due to water stress. In general, the abandoned agriculture land where food production is not economical, and has low inherent productivity potential is considered marginal; however, a land may be marginal for agriculture but vital for grazing. In this paper attempts have been made to give review of literature (water stress, extent of marginal saline lands, marginality. Policy matters (development of soil, water and agriculture strategies that GDLA and member countries should consider for future sustainable food production in their countries, including but not limited to, assessment of land resources for agriculture potential, defining, mapping and characterizing marginal lands, and use of innovative technologies (conservation agriculture, climate smart agriculture, integrated soil reclamation program and capacity building for food production, are discussed. The international perception (FAO, UNEP, CGIAR on marginal lands is also described. An innovative approach of using national biocapacity and ecological footprint is used to assess marginality of GDLA member countries. Ecological overshoot (using 1.5 earth planets and biocapacity debtor and creditor countries are highlighted. Challenges and best management practices for food production in marginal lands are included. Other important issues, like leasing land abroad, GDLA strategic food reserves and best management practices, innovative ideas for food production are shared. Finally recommendations are drafted for actions by GDLA, its member countries and the partners.

Identifying technology innovations for marginalized smallholders-A conceptual approach.

Science.gov (United States)

Malek, Mohammad Abdul; Gatzweiler, Franz W; Von Braun, Joachim

2017-05-01

This paper adds a contribution in the existing literature in terms of theoretical and conceptual background for the identification of idle potentials of marginal rural areas and people by means of technological and institutional innovations. The approach follows ex-ante assessment for identifying suitable technology and institutional innovations for marginalized smallholders in marginal areas-divided into three main parts (mapping, surveying and evaluating) and several steps. Finally, it contributes to the inclusion of marginalized smallholders by an improved way of understanding the interactions between technology needs, farming systems, ecological resources and poverty characteristics in the different segments of the poor, and to link these insights with productivity enhancing technologies.

Simulación de la señalización de un usuarío móvil y un usuario fijo usando simulación de la señalización de un usuario móvil y un usuario fijo usandosimulación de la señalización de un usuario móvil y un usuario fijo usando simulación de la señalización de un usuario móvil y un usuario fijo usando ss7

OpenAIRE

Lopez Masabanda, Reina Azucena; Escalante Guzman, Betsy Rosa; Medina Moreira, Washington

2014-01-01

El presente proyecto consiste en realizar la simulación de la señalización entre un usuario de telefonía móvil y un usuario de telefonía fija usando el protocolo SS7, el cual ilustrará el proceso de una llamada. El software a utilizar, conocido como OMNET ++, es un simulador discreto de redes, usado habitualmente para modelar el tráfico de redes de telecomunicaciones, protocolos, sistemas multiprocesadores y distribuidos, que permite representar de manera real diferentes tipos de procesos de ...

Evaluation of the marginal fit of metal copings fabricated on three different marginal designs using conventional and accelerated casting techniques: An in vitro study

Directory of Open Access Journals (Sweden)

Sharad Vaidya

2014-01-01

Conclusion: Among the three marginal designs studied, shoulder with bevel showed the best marginal fit with conventional as well as accelerated casting techniques. Accelerated casting technique could be a vital alternative to the time-consuming conventional casting technique. The marginal fit between the two casting techniques showed no statistical difference.

Marginal Accuracy of Castings Produced with Different Investment Systems.

Science.gov (United States)

Yadav, R K

2009-04-01

The use of casting ring to produce accurate castings has been challenged with the introduction of a ringless casting technique. This study compared the marginal accuracy of all - metal complete coverage crowns fabricated with ringless, split plastic ring and metal ring investment systems. A total of 40 all- metal complete coverage crowns were fabricated on a metal die. The crowns were divided in 4 groups (Group A, B, C and D) of 10 patterns each. A ringless system of investing and casting was used for group A whereas a split plastic ring system was used for group B. Groups C and D utilized metal ring with single and double layers of asbestos free cellulose acetate liner respectively for investing and casting procedures. The restorations were seated on the metal die and the vertical marginal discrepancy was evaluated by measuring the gap between the finish line on the die and the margins of the crown on four specific sites with an optical microscope. Statistical analysis was carried out using ANOVA and multiple comparison "t" test. The mean vertical marginal discrepancy for groups A, B, C and D was 95μm, 136μm, 128μm and 104μm respectively. Vertical marginal discrepancy on each surface was compared among the four groups. Difference of vertical marginal discrepancy on buccal surface (p0.05). Accurate castings with better marginal fit can be produced with ringless casting technique.

Influence of Crack Morphology on Leak Before Break Margins

International Nuclear Information System (INIS)

Weilin Zang

2007-11-01

The purpose of the project is to evaluate the deterministic LBB-margins for different pipe systems in a Swedish PWR-plant and using different crack morphology parameters. Results: - The influence of crack morphology on Leak Before Break (LBB) margins is studied. The subject of the report is a number of LBB-submittals to SKI where deterministic LBB-margins are reported. These submittals typically uses a surface roughness of 0.0762 mm (300 microinch) and number of turns equal to zero and an in-house code for the leak rate evaluations. The present report has shown that these conditions give the largest LBB-margins both in terms of the quotient between the critical crack length and the leakage crack size and for the leak rate margin. - Crack morphology parameters have a strong influence on the leak rate evaluations. Using the SQUIRT code and more recent recommendations for crack morphology parameters, it is shown that in many cases the evaluated margins, using 1 gpm as the reference leak rate detection limit, are below the safety factor of 2 on crack size and 10 on leak rate, which is generally required for LBB approval. - The effect of including weld residual stresses on the LBB margins is also investigated. It is shown that for the two examples studied, weld residual stresses were important for the small diameter thin wall pipe whereas it was negligible for the large diameter thick wall pipe which had a self-balanced weld residual stress distribution

Marginal adaptation of composite resins under two adhesive techniques.

Science.gov (United States)

Dačić, Stefan; Veselinović, Aleksandar M; Mitić, Aleksandar; Nikolić, Marija; Cenić, Milica; Dačić-Simonović, Dragica

2016-11-01

In the present research, different adhesive techniques were used to set up fillings with composite resins. After the application of etch and rinse or self etch adhesive technique, marginal adaptation of composite fillings was estimated by the length of margins without gaps, and by the microretention of resin in enamel and dentin. The study material consisted of 40 extracted teeth. Twenty Class V cavities were treated with 35% phosphorous acid and restored after rinsing by Adper Single Bond 2 and Filtek Ultimate-ASB/FU 3M ESPE composite system. The remaining 20 cavities were restored by Adper Easy One-AEO/FU 3M ESPE composite system. Marginal adaptation of composite fillings was examined using a scanning electron microscope (SEM). The etch and rinse adhesive technique showed a significantly higher percentage of margin length without gaps (in enamel: 92.5%, in dentin: 57.3%), compared with the self-etch technique with lower percentage of margin length without gaps, in enamel 70.4% (p resin tugs in interprismatic spaces of enamel, while the dentin microretention was composed of adhesive and hybrid layers with resin tugs in dentin canals. In the second technique, resin tugs were rarely seen and a microgap was dominant along the border of restoration margins. The SEM analysis showed a better marginal adaptation of composite resin to enamel and dentin with better microretention when the etch and rinse adhesive procedure was applied. © 2016 Wiley Periodicals, Inc.

Technical specification improvement through safety margin considerations

International Nuclear Information System (INIS)

Howard, R.C.; Jansen, R.L.

1986-01-01

Westinghouse has developed an approach for utilizing safety analysis margin considerations to improve plant operability through technical specification revision. This approach relies on the identification and use of parameter interrelations and sensitivities to identify acceptable operating envelopes. This paper summarizes technical specification activities to date and presents the use of safety margin considerations as another viable method to obtain technical specification improvement

Pattern of Failure After Limited Margin Radiotherapy and Temozolomide for Glioblastoma

International Nuclear Information System (INIS)

McDonald, Mark W.; Shu, Hui-Kuo G.; Curran, Walter J.; Crocker, Ian R.

2011-01-01

Purpose: To evaluate the pattern of failure after limited margin radiotherapy for glioblastoma. Methods and Materials: We analyzed 62 consecutive patients with newly diagnosed glioblastoma treated between 2006 and 2008 with standard fractionation to a total dose of 60Gy with concurrent temozolomide (97%) or arsenic trioxide (3%). The initial clinical target volume included postoperative T2 abnormality with a median margin of 0.7cm. The boost clinical target volume included residual T1-enhancing tumor and resection cavity with a median margin of 0.5cm. Planning target volumes added a 0.3- or 0.5-cm margin to clinical target volumes. The total boost planning target volume (PTV boost ) margin was 1cm or less in 92% of patients. The volume of recurrent tumor (new T1 enhancement) was categorized by the percent within the 60-Gy isodose line as central (>95%), infield (81-95%), marginal (20-80%), or distant ( boost with a 2.5-cm margin were created for each patient. Results: With a median follow-up of 12 months, radiographic tumor progression developed in 43 of 62 patients. Imaging was available for analysis in 41: 38 (93%) had central or infield failure, 2 (5%) had marginal failure, and 1 (2%) had distant failure relative to the 60-Gy isodose line. The treated PTV boost (median, 140cm 3 ) was, on average, 70% less than the PTV boost with a 2.5-cm margin (median, 477cm 3 ) (p boost margin of 1cm or less did not appear to increase the risk of marginal and/or distant tumor failures compared with other published series. With careful radiation planning and delivery, it appears that treatment margins for glioblastoma can be reduced.

Stroke: a Hidden Danger of Margin Trading in Stock Markets.

Science.gov (United States)

Lin, Shu-Hui; Wang, Chien-Ho; Liu, Tsai-Ching; Chen, Chin-Shyan

2015-10-01

Using 10-year population data from 2000 through 2009 in Taiwan, this is the first paper to analyze the relationship between margin trading in stock markets and stroke hospitalizations. The results show that 3 and 6 days after an increase of margin trading in the Taiwan stock markets are associated with greater stoke hospitalizations. In general, a 1 % increase in total margin trading positions is associated with an increment of 2.5 in the total number of stroke hospitalizations, where the mean number of hospital admissions is 233 cases a day. We further examine the effects of margin trading by gender and age groups and find that the effects of margin trading are significant for males and those who are 45-74 years old only. In summary, buying stocks with money you do not have is quite risky, especially if the prices of those stocks fall past a certain level or if there is a sudden and severe drop in the stock market. There is also a hidden danger to one's health from margin trading. A person should be cautious before conducting margin trading, because while it can be quite profitable, danger always lurks just around the corner.

Studying media at The Margins: learning from the field

Directory of Open Access Journals (Sweden)

Clemencia Rodríguez

2016-07-01

Full Text Available This article, informed by ethnographic research on media at the margins, proposes a shift in perspective at several different levels: 1 instead of focusing on individual technologies, our research should examine how grassroots communicators operating at the margins exist in a media ecology that offers different potentialities in each historical situation; 2 instead of trying to determine if the media technologies used at the margin are old or new, digital or not digital, we need to explore how embedded community communicators detect local information or communication needs and use available technologies to address these needs; 3 our research on media at the margins should shed light on how grassroots communicators re-invent, hybridize, converge, and bridge technologies from one platform to another. In sum, understanding media at the margins is about embracing complexity, maintaining the notion of media ecologies, and understanding how grassroots communicators, deeply embedded in local contexts, wedge media technologies into everyday life.

Uplift history of a transform continental margin revealed by the stratigraphic record: The case of the Agulhas transform margin along the Southern African Plateau

Science.gov (United States)

Baby, Guillaume; Guillocheau, François; Boulogne, Carl; Robin, Cécile; Dall'Asta, Massimo

2018-04-01

The south and southeast coast of southern Africa (from 28°S to 33°S) forms a high-elevated transform passive margin bounded to the east by the Agulhas-Falkland Fracture Zone (AFFZ). We analysed the stratigraphic record of the Outeniqua and Durban (Thekwini) Basins, located on the African side of the AFFZ, to determine the evolution of these margins from the rifting stage to present-day. The goal was to reconstruct the strike-slip evolution of the Agulhas Margin and the uplift of the inland high-elevation South African Plateau. The Agulhas transform passive margin results from four successive stages: Rifting stage, from Late Triassic to Early Cretaceous ( 200?-134 Ma), punctuated by three successive rifting episodes related to the Gondwana breakup; Wrench stage (134-131 Ma), evidenced by strike- and dip-slip deformations increasing toward the AFFZ; Active transform margin stage (131-92 Ma), during which the Falkland/Malvinas Plateau drifts away along the AFFZ, with an uplift of the northeastern part of the Outeniqua Basin progressively migrating toward the west; Thermal subsidence stage (92-0 Ma), marked by a major change in the configuration of the margin (onset of the shelf-break passive margin morphology). Two main periods of uplift were documented during the thermal subsidence stage of the Agulhas Margin: (1) a 92 Ma short-lived margin-scale uplift, followed by a second one at 76 Ma located along the Outeniqua Basin and; (2) a long-lasting uplift from 40 to 15 Ma limited to the Durban (Thekwini) Basin. This suggests that the South African Plateau is an old Upper Cretaceous relief (90-70 Ma) reactivated during Late Eocene to Early Miocene times (40-15 Ma).

Esquema de redundancia y distribución de carga de alta disponibilidad para la prestación de telefonía ip usando sip (junio 2009)

OpenAIRE

PARRA L., ANDRÉS; GUERRERO, FABIO G.

2010-01-01

En este artículo se presenta un esquema de distribución de carga y redundancia en la infraestructura de un ISP (Internet Service Provider) para la prestación de servicios de telefonía IP (ITSPs) sobre Internet usando el protocolo SIP (Session Initiation Protocol) garantizando niveles de acceso al servicio similares a la PSTN (Public Switched Telephone Network) y brindando una infraestructura de red escalable. La solución se plantea en tres partes: redundancia del servicio y distribución de ca...

The determinants of intermediaries’ power over farmers’ margin-related activities

DEFF Research Database (Denmark)

Xhoxhi, Orjon; Pedersen, Søren Marcus; Lind, Kim Martin Hjorth

2014-01-01

This paper investigates the determinants of intermediaries’ power over farmers’ margin-related activities in Adana, Turkey. In doing so, a holistic model of intermediaries’ power over farmers’ margin-related activities is proposed. The objective of this model is to contribute to a better understa......This paper investigates the determinants of intermediaries’ power over farmers’ margin-related activities in Adana, Turkey. In doing so, a holistic model of intermediaries’ power over farmers’ margin-related activities is proposed. The objective of this model is to contribute to a better...

Volcanic passive margins: another way to break up continents.

Science.gov (United States)

Geoffroy, L; Burov, E B; Werner, P

2015-10-07

Two major types of passive margins are recognized, i.e. volcanic and non-volcanic, without proposing distinctive mechanisms for their formation. Volcanic passive margins are associated with the extrusion and intrusion of large volumes of magma, predominantly mafic, and represent distinctive features of Larges Igneous Provinces, in which regional fissural volcanism predates localized syn-magmatic break-up of the lithosphere. In contrast with non-volcanic margins, continentward-dipping detachment faults accommodate crustal necking at both conjugate volcanic margins. These faults root on a two-layer deformed ductile crust that appears to be partly of igneous nature. This lower crust is exhumed up to the bottom of the syn-extension extrusives at the outer parts of the margin. Our numerical modelling suggests that strengthening of deep continental crust during early magmatic stages provokes a divergent flow of the ductile lithosphere away from a central continental block, which becomes thinner with time due to the flow-induced mechanical erosion acting at its base. Crustal-scale faults dipping continentward are rooted over this flowing material, thus isolating micro-continents within the future oceanic domain. Pure-shear type deformation affects the bulk lithosphere at VPMs until continental breakup, and the geometry of the margin is closely related to the dynamics of an active and melting mantle.

Preoperative imaging and surgical margins in maxillectomy patients

NARCIS (Netherlands)

Kreeft, Anne Marijn; Smeele, Ludwig E.; Rasch, Coen R. N.; Hauptmann, Michael; Rietveld, Derk H. F.; Leemans, C. René; Balm, Alfons J. M.

2012-01-01

Background High rates of positive surgical margins are reported after a maxillectomy. A large part of tumors that are preoperatively considered operable can thus not be resected with tumor-free margins. Methods This was a retrospective study on medical files of 69 patients that underwent

Effect of post-implant edema on prostate brachytherapy treatment margins

International Nuclear Information System (INIS)

Reed, Daniel R.; Wallner, Kent; Ford, Eric; Mueller, Amy; Merrick, Gregory; Maki, Jeffrey; Sutlief, Steven; Butler, Wayne

2005-01-01

Purpose: To determine if postimplant prostate brachytherapy treatment margins calculated on Day 0 differ substantially from those calculated on Day 30. Methods: Thirty patients with 1997 American Joint Commission on Cancer clinical stage T1-T2 prostatic carcinoma underwent prostate brachytherapy with I-125 prescribed to 144 Gy. Treatment planning methods included using loose seeds in a modified peripheral loading pattern and treatment margins (TMs) of 5-8 mm. Postimplant plain radiographs, computed tomography scans, and magnetic resonance scans were obtained 1-4 hours after implantation (Day 0). A second set of imaging studies was obtained at 30 days after implantation (Day 30) and similarly analyzed. Treatment margins were measured as the radial distance in millimeters from the prostate edge to the 100% isodose line. The TMs were measured and tabulated at 90 o intervals around the prostate periphery at 0.6-cm intervals. Each direction was averaged to obtain the mean anterior, posterior, left, and right margins. Results: The mean overall TM increased from 2.6 mm (±2.3) on Day 0 to 3.5 mm (±2.4) on Day 30. The mean anterior margin increased from 1.2 mm on Day 0 to 1.8 mm on Day 30. The posterior margin increased from 1.2 mm on Day 0 to 2.8 mm on Day 30. The lateral treatment margins increased most over time, with mean right treatment margin increasing from 3.9 mm on Day 0 to 4.7 mm on Day 30. Conclusion: Treatment margins appear to be durable in the postimplant period, with a clinically insignificant increase from Day 0 to Day 30

STUDI PERBANDINGAN ANTARA ALGORITMA BIVARIATE MARGINAL DISTRIBUTION DENGAN ALGORITMA GENETIKA

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Chastine Fatichah

2006-01-01

Full Text Available Bivariate Marginal Distribution Algorithm is extended from Estimation of Distribution Algorithm. This heuristic algorithm proposes the new approach for recombination of generate new individual that without crossover and mutation process such as genetic algorithm. Bivariate Marginal Distribution Algorithm uses connectivity variable the pair gene for recombination of generate new individual. Connectivity between variable is doing along optimization process. In this research, genetic algorithm performance with one point crossover is compared with Bivariate Marginal Distribution Algorithm performance in case Onemax, De Jong F2 function, and Traveling Salesman Problem. In this research, experimental results have shown performance the both algorithm is dependence of parameter respectively and also population size that used. For Onemax case with size small problem, Genetic Algorithm perform better with small number of iteration and more fast for get optimum result. However, Bivariate Marginal Distribution Algorithm perform better of result optimization for case Onemax with huge size problem. For De Jong F2 function, Genetic Algorithm perform better from Bivariate Marginal Distribution Algorithm of a number of iteration and time. For case Traveling Salesman Problem, Bivariate Marginal Distribution Algorithm have shown perform better from Genetic Algorithm of optimization result. Abstract in Bahasa Indonesia : Bivariate Marginal Distribution Algorithm merupakan perkembangan lebih lanjut dari Estimation of Distribution Algorithm. Algoritma heuristik ini mengenalkan pendekatan baru dalam melakukan rekombinasi untuk membentuk individu baru, yaitu tidak menggunakan proses crossover dan mutasi seperti pada Genetic Algorithm. Bivariate Marginal Distribution Algorithm menggunakan keterkaitan pasangan variabel dalam melakukan rekombinasi untuk membentuk individu baru. Keterkaitan antar variabel tersebut ditemukan selama proses optimasi berlangsung. Aplikasi yang

Consideration of margins for hypo fractionated radiotherapy

International Nuclear Information System (INIS)

Herschtal, A.; Foroudi, F.; Kron, T.

2010-01-01

Full text: Geographical misses of the tumour are of concern in radiotherapy and are typically accommodated by introducing margins around the target. However, there is a trade-off between ensuring the target receives sufficient dose and minimising the dose to surrounding normal structures. Several methods of determining margin width have been developed with the most commonly used one proposed by M. VanHerk (VanHerk UROBP 52: 1407, 2002). VanHerk's model sets margins to achieve 95% of dose coverage for the target in 90% of patients. However, this model was derived assuming an infinite number of fractions. The aim of the present work is to estimate the modifications necessary to the model if a finite number of fractions are given. Software simulations were used to determine the true probability of a patient achieving 95% target coverage if different fraction numbers are used for a given margin width. Model parameters were informed by a large data set recently acquired at our institution using daily image guidance for prostate cancer patients with implanted fiducial markers. Assuming a 3 mm penumbral width it was found that using the VanHerk model only 74 or 54% of patients receive 95% of the prescription dose if 20 or 6 fractions are given, respectively. The steep dose gradients afforded by IMRT are likely to make consideration of the effects of hypofractionation more important. It is necessary to increase the margins around the target to ensure adequate tumour coverage if hypofractionated radiotherapy is to be used for cancer treatment. (author)

Influence of Different Ceramic Systems on Marginal Misfit.

Science.gov (United States)

Vargas, S P; Neves, A C C; Vitti, R; Amaral, M; Henrique, M N; Silva-Concílio, L R

2017-09-01

the aim of this study was to evaluate the marginal misfit at the interface between a ceramic coping and its abutment. Twenty-four specimens were made with solid abutments. The specimens were divided into 3 groups according to the ceramic system (n = 8): Lava (zirconia), IPS e.max Press (lithium disilicate), and IPS Empress Esthetic (leucite). All copings were cemented with resin luting agent (RelyX U200) and the marginal misfit were evaluated at 3 different times: initial, after cementation, and after mechanical cycling using a linear measuring microscope (Measuring Microscope STM-Olympus) at a magnification of 40x. All specimens were subjected to mechanical cycling (1 million cycles) by an universal testing machine (Instron 8800). The results were statistically analyzed using Analysis of Variance and Student's t-test (α = 0.05). all groups showed an increase in the marginal misfit after cementation. The lithium disilicate group demonstrated the lowest interacial gap values at each evaluation (p = 0.001). The zirconia and leucite groups showed similar interfacial gap values (initial, p = 0.244; and post cementation, p = 0.751). the cementation increase the marginal misfit, but the mechanical cycling did not influence the marginal misfit of the ceramics systems evaluated. Copyright© 2017 Dennis Barber Ltd.

Validação de simulações combinadas usando programas de simulação de energia do edifício e programas de transferência de calor, ar e umidade em componentes construtivos

NARCIS (Netherlands)

Costola, D.; Blocken, B.J.E.; Hensen, J.L.M.

2011-01-01

Desempenho higrotérmico dos edifícios tem sido estudado usando uma variedade de programas de computador, os quais consideram determinados domínios geométricos (exterior, envelope e interior) e físicos (calor, ar e umidade). Estes programas podem ser classificados em três principais grupos: programas

Determinants of banks’ net interest margins in Central and Eastern Europe

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Tomislav Rizdak

2013-03-01

Full Text Available This research analyzes the main determinants of the net interest margin of banks operating in Central and Eastern European (CEE countries in the period from 1999 to 2010. The results reveal several main drivers of net interest margins in the CEE. Prior to 2008 the net interest margins declined primarily due to strong capital inflows and stable macroeconomic environment. In the crisis period, significant rise in government debt accompanied by the increase in macroeconomic risks and abating capital inflows were pushing margins up while other factors such as low credit demand, higher capitalization and significantly increased share of non-performing loans pressured banks’ margins down. The results also confirm the important contribution of higher efficiency to lowering banks’ margins.

Marginal Assessment of Crowns by the Aid of Parallel Radiography

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Farnaz Fattahi

2015-03-01

Full Text Available Introduction: Marginal adaptation is the most critical item in long-term prognosis of single crowns. This study aimed to assess the marginal quality as well asthe discrepancies in marginal integrity of some PFM single crowns of posterior teeth by employing parallel radiography in Shiraz Dental School, Shiraz, Iran. Methods: In this descriptive study, parallel radiographies were taken from 200 fabricated PFM single crowns of posterior teeth after cementation and before discharging the patient. To calculate the magnification of the images, a metallic sphere with the thickness of 4 mm was placed in the direction of the crown margin on the occlusal surface. Thereafter, the horizontal and vertical space between the crown margins, the margin of preparations and also the vertical space between the crown margin and the bone crest were measured by using digital radiological software. Results: Analysis of data by descriptive statistics revealed that 75.5% and 60% of the cases had more than the acceptable space (50µm in the vertical (130±20µm and horizontal (90±15µm dimensions, respectively. Moreover, 85% of patients were found to have either horizontal or vertical gap. In 77% of cases, the margins of crowns invaded the biologic width in the mesial and 70% in distal surfaces. Conclusion: Parallel radiography can be expedient in the stage of framework try-in to yield some important information that cannot be obtained by routine clinical evaluations and may improve the treatment prognosis

Supervised linear dimensionality reduction with robust margins for object recognition

Science.gov (United States)

Dornaika, F.; Assoum, A.

2013-01-01

Linear Dimensionality Reduction (LDR) techniques have been increasingly important in computer vision and pattern recognition since they permit a relatively simple mapping of data onto a lower dimensional subspace, leading to simple and computationally efficient classification strategies. Recently, many linear discriminant methods have been developed in order to reduce the dimensionality of visual data and to enhance the discrimination between different groups or classes. Many existing linear embedding techniques relied on the use of local margins in order to get a good discrimination performance. However, dealing with outliers and within-class diversity has not been addressed by margin-based embedding method. In this paper, we explored the use of different margin-based linear embedding methods. More precisely, we propose to use the concepts of Median miss and Median hit for building robust margin-based criteria. Based on such margins, we seek the projection directions (linear embedding) such that the sum of local margins is maximized. Our proposed approach has been applied to the problem of appearance-based face recognition. Experiments performed on four public face databases show that the proposed approach can give better generalization performance than the classic Average Neighborhood Margin Maximization (ANMM). Moreover, thanks to the use of robust margins, the proposed method down-grades gracefully when label outliers contaminate the training data set. In particular, we show that the concept of Median hit was crucial in order to get robust performance in the presence of outliers.

Influence of margin segmentation and anomalous volcanism upon the break-up of the Hatton Bank rifted margin, west of the UK

Science.gov (United States)

Elliott, G. M.; Parson, L. M.

2007-12-01

The Hatton Bank margin, flanking the Iceland Basin is a widely cited example of a volcanic rifted margin. Prior to this study insights into the break-up history of the margin have been limited to profiles in the north and south, yet whilst valuable, the along margin tectono-magmatic variability has not been revealed. Over 5660 line km of high quality reflection seismic profiles with supplementary multibeam bathymetry were collected to support the UK's claim to Hatton region under the United Nations Convention on Law of the Sea (UNCLOS). Integration of this new data with existing profiles, allowed the margin to be divided into three segments, each of which are flanked by oceanic crust with a smooth upper surface and internal dipping reflectors. The southernmost segment is characterised by a series of inner and outer seaward dipping reflector (SDR) packages, which are separated by an outer high feature. The outer SDR are truncated by Endymion Spur, a chain of steep sided, late stage volcanic cones linked with necks. The central sector has no inner SDR package and is characterised by the presence of a highly intruded continental block, the Hatton Bank Block (HBB). The northern sector is adjacent to Lousy Bank, with a wider region of SDR recognised than to the south and a high amount of volcanic cones imaged. The variations in the distribution of the SDR's along the margin, the presence of the HBB and Endymion Spur all suggest that the break-up process was not uniform alongstrike. The division of the margin into three sectors reveals that structural segmentation played an important role in producing the variations along the margin. Break- up initiated in the south and progressed north producing the SDR packages witnessed, when the HBB was encountered the focus of break-up moved seaward of the block. The northern sector was closer to the Iceland Hotspot and hence a greater amount of volcanism is encountered. The smooth oceanic basement also indicates a high thermal flux

Slope failure of chalk channel margins

DEFF Research Database (Denmark)

Gale, A.; Anderskouv, Kresten; Surlyk, Finn

2015-01-01

provide evidence for recurring margin collapse of a long-lived Campanian channel. Compressionally deformed and thrust chalk hardgrounds are correlated to thicker, non-cemented chalk beds that form a broad, gentle anticline. These chalks represent a slump complex with a roll-over anticline of expanded, non......-cemented chalk in the head region and a culmination of condensed hardgrounds in the toe region. Observations strongly suggest that the slumping represents collapse of a channel margin. Farther northwards, the contemporaneous succession shows evidence of small-scale penecontemporaneous normal faulting towards...

Perennial Grass Bioenergy Cropping on Wet Marginal Land

NARCIS (Netherlands)

Das, Srabani; Teuffer, Karin; Stoof, Cathelijne R.; Walter, Michael F.; Walter, M.T.; Steenhuis, Tammo S.; Richards, Brian K.

2018-01-01

The control of soil moisture, vegetation type, and prior land use on soil health parameters of perennial grass cropping systems on marginal lands is not well known. A fallow wetness-prone marginal site in New York (USA) was converted to perennial grass bioenergy feedstock production. Quadruplicate

Helping Students on the Margin Succeed in Schools.

Science.gov (United States)

Langenfeld, Michelle Schoen; Cumming, Brenda

1996-01-01

Addresses how Apple Valley High School (Minnesota) has been able to help marginal students succeed in school. The fundamental actions that contributed to the effectiveness of study-team efforts to help marginal students are discussed, and what has been learned through these efforts is considered. (GR)

Principals' Perceived Supervisory Behaviors Regarding Marginal Teachers in Two States

Science.gov (United States)

Range, Bret; Hewitt, Paul; Young, Suzie

2014-01-01

This descriptive study used an online survey to determine how principals in two states viewed the supervision of marginal teachers. Principals ranked their own evaluation of the teacher as the most important factor when identifying marginal teachers and relied on informal methods to diagnose marginal teaching. Female principals rated a majority of…

Predicción de los precios de contratos de electricidad usando una red neuronal con arquitectura dinámica

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Juan David Velásquez Henao

2010-04-01

Full Text Available Los contratos en los mercados liberalizados de electricidad constituyen una herramienta para proteger a los agentes de la volatilidad; en este contexto, los pronósticos de los precios son una entrada clave para la toma de decisiones estratégicas y operativas de los agentes. En este artículo, se pronostican los precios promedios de los contratos despachados en el mercado eléctrico colombiano, usando una red neuronal con arquitectura dinámica conocida como DAN2. El modelo desarrollado es capaz de capturar la dinámica intrínseca de la serie de precios y de pronosticar el precio para el siguiente mes con más precisión que la metodología ARIMA clásica, para horizontes de predicción de 12 y 24 meses

Quantifying Safety Margin Using the Risk-Informed Safety Margin Characterization (RISMC)

Energy Technology Data Exchange (ETDEWEB)

Grabaskas, David; Bucknor, Matthew; Brunett, Acacia; Nakayama, Marvin

2015-04-26

The Risk-Informed Safety Margin Characterization (RISMC), developed by Idaho National Laboratory as part of the Light-Water Reactor Sustainability Project, utilizes a probabilistic safety margin comparison between a load and capacity distribution, rather than a deterministic comparison between two values, as is usually done in best-estimate plus uncertainty analyses. The goal is to determine the failure probability, or in other words, the probability of the system load equaling or exceeding the system capacity. While this method has been used in pilot studies, there has been little work conducted investigating the statistical significance of the resulting failure probability. In particular, it is difficult to determine how many simulations are necessary to properly characterize the failure probability. This work uses classical (frequentist) statistics and confidence intervals to examine the impact in statistical accuracy when the number of simulations is varied. Two methods are proposed to establish confidence intervals related to the failure probability established using a RISMC analysis. The confidence interval provides information about the statistical accuracy of the method utilized to explore the uncertainty space, and offers a quantitative method to gauge the increase in statistical accuracy due to performing additional simulations.

Development and function of the splenic marginal zone

NARCIS (Netherlands)

Mebius, Reina E.; Nolte, Martijn A.; Kraal, Georg

2004-01-01

The marginal zone of the spleen is a crucial region where blood-borne pathogens are sequestered by macrophages with unique arrays of scavenger molecules. In addition, a special population of B cells, which is capable of rapid activation, resides in this region. Marginal zone B cells and macrophages

Marginal Leakage of Class V Composite Resin Restorations

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Maryam Khoroushi

2018-01-01

Full Text Available >Introduction: Marginal leakage is one of the significant causes of restoration failure. This in-vitro study was conducted to compare cone beam computed tomography (CBCT and dye-penetration methods for determining marginal leakage at gingival surface of class V resin composite restorations.Materials and Methods: Class V cavities were prepared on the buccal surfaces of nineteen caries-free extracted human molar teeth. Cavities were conditioned and filled. The teeth were immersed in a 50% w/w aqueous silver nitrate solution for 24 h and were taken out and rinsed with distilled water. Then, they were put into a developing solution. Whole specimens were first viewed with CBCT and were then sectioned and evaluated by stereomicroscope.Results: Measurement of agreement between CBCT and stereomicroscope revealed that 15 (78.9% teeth had score 0, 1 (5.3% tooth had score 1, and 1 (5.3% tooth had score 2 in both techniques. Measurement of agreement between CBCT and stereomicroscope techniques, in the detection of marginal leakage, was 89.5% (Kappa coefficient = 0.627, P = 0.00. The Wilcoxon paired rank test revealed no significant difference between the results of CBCT and stereomicroscope in measuring the leakage at gingival margin (P = 0.157.Conclusion: Considering the limitations of the study, there was no significant difference between the results of CBCT and stereomicroscope in measuring the leakage at gingival margin of class V composite restorations. CBCT can be used noninvasively to detect the marginal leakage of gingival wall of class V composite restorations using aqueous silver nitrate solution as a tracer.

Marginally Deformed Starobinsky Gravity

DEFF Research Database (Denmark)

Codello, A.; Joergensen, J.; Sannino, Francesco

2015-01-01

We show that quantum-induced marginal deformations of the Starobinsky gravitational action of the form $R^{2(1 -\\alpha)}$, with $R$ the Ricci scalar and $\\alpha$ a positive parameter, smaller than one half, can account for the recent experimental observations by BICEP2 of primordial tensor modes....

Komorbiditet ved marginal parodontitis

DEFF Research Database (Denmark)

Holmstrup, Palle; Damgaard, Christian; Olsen, Ingar

2017-01-01

Nærværende artikel præsenterer en oversigt over den foreliggende væsentligste viden om sammenhængen mellem marginal parodontitis og en række medicinske sygdomme, herunder hjerte-kar-sygdomme, diabetes mellitus, reumatoid arthritis, osteoporose, Parkinsons sygdom, Alzheimers sygdom, psoriasis og...

From marginality to further marginalization: Experiences from the victims of the July 2000 Payatas trashslide in the Philippines

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JC Gaillard

2009-04-01

Full Text Available Victims of disasters are disproportionately drawn from the marginalized segments of society. Disaster victims are marginalized geographically because they live in hazardous places, socially because they are members of minority groups, economically because they are poor, and marginalized politically because their voice is disregarded by those with political power. #e victims of the July 2000 Payatas trash slide in the Philippines show all these characteristics. Most of the victims of the disaster were urban migrants who came all the way from their poor provinces to settle on the lower slopes of the largest dumpsite of the country. #ey scavenged recyclable materials to sell as a way to make a living, but their limited incomes did not allow them to a$ord safer locations for their homes, farther removed from the slopes of the dumpsite. On the morning of 10 July 2000, 300 of them lost their lives when a large section of the dumpsite collapsed in a massive debris %ow which buried their houses. In the aftermath of the disaster, the survivors who used to live on the dumpsite, and who were the poorest victims, were also those who were relocated by the Philippine government. In the present case, the most vulnerable families in the face of the trash slide were eventually those who had to su#er again from life-disrupting relocation while being the less able to recover quickly from the disaster. Daily incomes of relocated families are today much lower than those who remained in the vicinity of the dumpsite. For the victims of the July 2000 Payatas tragedy, poverty thus acted as a vicious, worsening circle which ranged from vulnerability to poor recovery, or from marginality to further marginalization.

Intraoperative monitoring of marginal mandibular nerve during neck dissection.

Science.gov (United States)

Tirelli, Giancarlo; Bergamini, Pier Riccardo; Scardoni, Alessandro; Gatto, Annalisa; Boscolo Nata, Francesca; Marcuzzo, Alberto Vito

2018-05-01

The purpose of this study was to assess the efficacy of intraoperative nerve integrity monitoring (NIM) to prevent marginal mandibular nerve injuries during neck dissection. This prospective study compared 36 patients undergoing NIM-assisted neck dissection from July 2014 to March 2015 to a cohort of 35 patients subjected to neck dissection over an identical period of time before the technique was introduced. We also assessed possible correlations between marginal mandibular nerve injuries and other factors, such as anthropometric measurements, presence of clinical neck metastases, type of neck dissection, and site of primary tumor. The incidence of marginal mandibular nerve paralyses was significantly lower among the group of patients undergoing NIM-assisted neck dissection (P = .021). There was no significant difference in the duration of the procedure, and the technique resulted in a limited increase of cost. No other factor seemed to influence the onset of marginal mandibular nerve palsy. In our opinion, NIM is a valuable aid for preventing marginal mandibular nerve injuries during neck dissection. © 2018 Wiley Periodicals, Inc.

Radiotherapy Results of Carcinoma of Cervix with positive Resection Margin

International Nuclear Information System (INIS)

Huh, Seung Jae; Kim, Dae Yong; Ahn, Yong Chan; Kim, Won Dong; Wu, Hong Gyun; Ha, Sung Whan; Kim, Il Han; Park, Charn Il

1996-01-01

Purpose : Patients with cervical cancer who have positive resection margins after radical hysterectomy are at increased risk for local recurrence. The results of postoperative pelvic radiotherapy for cervix cancer with positive resection margins were analyzed to evaluated the role of radiotherapy. Materials and Methods : Between 1979 and 1992, 60 patients of cervix carcinoma were treated with postoperative radiotherapy after radical hysterectomy because of positive vaginal(48 patients) or parametrial resection margins(12 patients). Patients were treated with external beam radiation therapy(EBRT) alone (12 patients) or EBRT plus vaginal ovoid irradiation (VOI) (48 patients). The median follow-up period was 5 months. Results : The 5-year actuarial disease free and overall survival rates for all patients were 75.2%, 84.1%, respectively. The overall recurrence rate was 23%(14/60). In 48 patients with positive vaginal resection margins, the pelvic recurrence was 8%(4/48). Distant metastasis was 15%(7/48). Of the 43 patients with positive vaginal resection margins treated with EBRT and VOI, recurrence rate was 21%(9/43), while recurrence rate was 40%(2/5) in the EBRT only treated group. In 12 patients with positive parametrial margins, three patients (25%) had distant metastases. The most significant prognostic factor was lymph node metastasis. Complications resulting from radiotherapy occurred at a rate of 32%(19/60) and grade III complications occurred in three patients (5%). Conclusion : Postoperative radiotherapy can produce excellent pelvic control rates in patients with positive resection margins. In patients with positive vaginal margins, whole pelvic EBRT and BOI is recommended

Marginal pricing of transmission services: An analysis of cost recovery

Energy Technology Data Exchange (ETDEWEB)

Perez-Arriaga, I.J.; Rubio, F.J. [Univ. Pontificia Comillas, Madrid (Spain); Puerta, J.F.; Arceluz, J.; Marin, J. [IBERDROLA, Bilbao (Spain). Unidad de Planificacion Estrategica

1995-02-01

This paper presents an in-depth analysis of network revenues computed with marginal pricing, and in particular it investigates the reasons why marginal prices fail to recover the total incurred network costs in actual power systems. The basic theoretical results are presented and the major causes of the mismatch between network costs and marginal revenues are identified and illustrated with numerical examples, some tutorial and others of realistic size. The regulatory implications of marginal network pricing in the context of competitive electricity markets are analyzed, and suggestions are provided for the meaningful allocation of the costs of the network among its users.

Marginal pricing of transmission services: An analysis of cost recovery

International Nuclear Information System (INIS)

Perez-Arriaga, I.J.; Rubio, F.J.; Puerta, J.F.; Arceluz, J.; Marin, J.

1995-01-01

This paper presents an in-depth analysis of network revenues computed with marginal pricing, and in particular it investigates the reasons why marginal prices fail to recover the total incurred network costs in actual power systems. The basic theoretical results are presented and the major causes of the mismatch between network costs and marginal revenues are identified and illustrated with numerical examples, some tutorial and others of realistic size. The regulatory implications of marginal network pricing in the context of competitive electricity markets are analyzed, and suggestions are provided for the meaningful allocation of the costs of the network among its users

Evaluation of the marginal fit of metal copings fabricated on three different marginal designs using conventional and accelerated casting techniques: an in vitro study.

Science.gov (United States)

Vaidya, Sharad; Parkash, Hari; Bhargava, Akshay; Gupta, Sharad

2014-01-01

Abundant resources and techniques have been used for complete coverage crown fabrication. Conventional investing and casting procedures for phosphate-bonded investments require a 2- to 4-h procedure before completion. Accelerated casting techniques have been used, but may not result in castings with matching marginal accuracy. The study measured the marginal gap and determined the clinical acceptability of single cast copings invested in a phosphate-bonded investment with the use of conventional and accelerated methods. One hundred and twenty cast coping samples were fabricated using conventional and accelerated methods, with three finish lines: Chamfer, shoulder and shoulder with bevel. Sixty copings were prepared with each technique. Each coping was examined with a stereomicroscope at four predetermined sites and measurements of marginal gaps were documented for each. A master chart was prepared for all the data and was analyzed using Statistical Package for the Social Sciences version. Evidence of marginal gap was then evaluated by t-test. Analysis of variance and Post-hoc analysis were used to compare two groups as well as to make comparisons between three subgroups . Measurements recorded showed no statistically significant difference between conventional and accelerated groups. Among the three marginal designs studied, shoulder with bevel showed the best marginal fit with conventional as well as accelerated casting techniques. Accelerated casting technique could be a vital alternative to the time-consuming conventional casting technique. The marginal fit between the two casting techniques showed no statistical difference.

Efectividad de una intervención comunitaria en salud oral: resultados después de 18 meses.

Directory of Open Access Journals (Sweden)

Eduardo BERNABÉ ORTIZ

2006-07-01

Full Text Available Objetivo: Evaluar la efectividad de una intervención comunitaria en salud oral, dirigida a niños entre 6 y 14 años de edad de comunidades urbano-marginales de Sol Naciente (Carabayllo, realizada por estudiantes de pregrado de la Facultad de Estomatología Roberto Beltrán Neira de la Universidad Peruana Cayetano Heredia. Materiales y métodos: Ciento doce niños fueron cubiertos en la intervención preventivo-promocional hasta la evaluación a los 18 meses. La efectividad fue evaluada midiendo la variación en la prevalencia y experiencia de caries dental, así como también en el nivel de obturaciones, higiene oral y proporción de molares permanentes sellados y obturados al inicio y a los 18 meses de la intervención. Resultados: No hubo variación significativa en la prevalencia y experiencia de caries dental entre ambas evaluaciones. Sin embargo, se encontró una mejora significativa en la proporción de dientes y superficies cariadas que fueron obturados (p < 0,001 y p = 0,015 respectivamente, en el nivel de higiene oral (p < 0,001 y en la proporción de molares permanentes sellados y obturados (p < 0,001 en ambos casos. Conclusiones: Los presentes resultados indican que la intervención fue efectiva en el control de caries dental y en la mejora de los niveles de obturaciones e higiene oral así como de la proporción de molares permanentes sellados y obturados en los niños evaluados. Se requieren futuros estudios para evaluar la efectividad y costos de intervenciones similares en el Perú (Rev Med Hered 2006;17:170-176.

Systems considerations in seismic margin evaluations

International Nuclear Information System (INIS)

Buttermer, D.R.

1987-01-01

Increasing knowledge in the geoscience field has led to the understanding that, although highly unlikely, it is possible for a nuclear power plant to be subjected to earthquake ground motion greater than that for which the plant was designed. While it is recognized that there are conservatisms inherent in current design practices, interest has developed in evaluating the seismic risk of operating plants. Several plant-specific seismic probabilistic risk assessments (SPRA) have been completed to address questions related to the seismic risk of a plant. The results from such SPRAs are quite informative, but such studies may entail a considerable amount of expensive analysis of large portions of the plant. As an alternative to an SPRA, it may be more practical to select an earthquake level above the design basis for which plant survivability is to be demonstrated. The principal question to be addressed in a seismic margin evaluation is: At what ground motion levels does one have a high confidence that the probability of seismically induced core damage is sufficiently low? In a seismic margin evaluation, an earthquake level is selected (based on site-specific geoscience considerations) for which a stable, long-term safe shutdown condition is to be demonstrated. This prespecified earthquake level is commonly referred to as the seismic margin earthquake (SME). The Electric Power Research Institute is currently supporting a research project to develop procedures for use by the utilities to allow them to perform nuclear plant seismic margin evaluations. This paper describes the systems-related aspects of these procedures

Radiotherapy margin design with particular consideration of high curvature CTVs

International Nuclear Information System (INIS)

Herschtal, Alan; Kron, Tomas; Fox, Chris

2009-01-01

In applying 3D conformal radiation therapy to a tumor clinical target volume (CTV), a margin is added around the CTV to account for any sources of error in the application of treatment which may result in misalignment between the CTV and the dose distribution actually delivered. The volume enclosed within the CTV plus the margin is known as the PTV, or planning target volume. The larger the errors are anticipated to be, the wider the margin will need to be to accommodate those errors. Based on the approach of van Herk et al. [''The probability of correct target dosage: Dose-population histograms for deriving treatment margins in radiotherapy,'' Int. J. Radiat. Oncol. Biol., Phys. 47(4), 1121-1135 (2000)] this paper develops the mathematical theory behind the calculation of the margin width required to ensure that the entire CTV receives sufficiently high dose with sufficiently high probability. The margin recipe developed not only considers the magnitude of the errors but also includes a term to adjust for curved CTV surfaces. In doing so, the accuracy of the margin recipe is enhanced yet remains mathematically concise enough to be readily implemented in the clinical setting. The results are particularly relevant for clinical situations in which the uncertainties in treatment are large relative to the size of the CTV.

Marginal Pricing and Student Investment in Higher Education

Science.gov (United States)

Hemelt, Steven W.; Stange, Kevin M.

2016-01-01

This paper examines the effect of marginal price on students' educational investments using rich administrative data on students at Michigan public universities. Marginal price refers to the amount colleges charge for each additional credit taken in a semester. Institutions differ in how they price credits above the full-time minimum (of 12…

Short-term marginal costs in French agriculture

OpenAIRE

Latruffe, Laure; LETORT, Elodie

2011-01-01

The paper investigates short-term marginal costs in French agriculture for field cropping, beef cattle, and dairy farms during the period 1995-2006. The multi-input multi-output Symmetric Generalised MacFadden cost function is used, with three variable inputs (crop-specific, animal-specific, energy costs), four outputs and three quasi-fixed inputs. Results indicate that marginal costs are on average lower for crop farms than for livestock samples. However, for crop farms, Common Agricultural ...

Are subduction zones invading the atlantic? Evidence from the southwest iberia margin

NARCIS (Netherlands)

Duarte, João C.; Rosas, Filipe M.; Terrinha, Pedro; Schellart, Wouter P.; Boutelier, David; Gutscher, Marc André; Ribeiro, António

Subduction initiation at passive margins plays a central role in the plate tectonics theory. However, the process by which a passive margin becomes active is not well understood. In this paper we use the southwest Iberia margin (SIM) in the Atlantic Ocean to study the process of passive margin

Deregulated model and locational marginal pricing

International Nuclear Information System (INIS)

Sood, Yog Raj; Padhy, N.P.; Gupta, H.O.

2007-01-01

This paper presents a generalized optimal model that dispatches the pool in combination with privately negotiated bilateral and multilateral contracts while maximizing social benefit has been proposed. This model determines the locational marginal pricing (LMP) based on marginal cost theory. It also determines the size of non-firm transactions as well as pool demand and generations. Both firms as well as non-firm transactions are considered in this model. The proposed model has been applied to IEEE-30 bus test system. In this test system different types of transactions are added for analysis of the proposed model. (author)

Comportamiento del aluminio desnudo y anodizado en atmósferas con grados de contaminación muy diferentes

Directory of Open Access Journals (Sweden)

Bautista, A.

1998-05-01

Full Text Available In the present research, the responses of unprotected and anodized aluminium specimens are compared after they have been exposed to 12 different atmospheres. The significance of the anodizing and the sealing on the atmospheric corrosion behaviour is analysed. The results show that the anodizing and sealing of aluminium exclude the risk of pitting corrosion in marine atmospheres and that the oxide thickness is not determining, at least during the first year of exposure.

En la presente investigación, comparando las respuestas de muestras de aluminio desnudas y anodizadas, expuestas a 12 atmósferas diferentes, se analiza la repercusión del anodizado y sellado del aluminio en el comportamiento frente a la corrosión atmosférica. Se demuestra que la anodización y sellado del aluminio elimina el riesgo de corrosión por picaduras que afecta a estos materiales en atmósferas marinas, sin que el espesor del recubrimiento resulte determinante, al menos, en el primer año de exposición.

30 CFR 204.4 - What is a marginal property under this part?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What is a marginal property under this part... REVENUE MANAGEMENT ALTERNATIVES FOR MARGINAL PROPERTIES General Provisions § 204.4 What is a marginal property under this part? (a) To qualify as a marginal property eligible for royalty prepayment or...

Systematic reviews: I. The correlation between laboratory tests on marginal quality and bond strength. II. The correlation between marginal quality and clinical outcome.

Science.gov (United States)

Heintze, Siegward D

2007-01-01

An accepted principle in restorative dentistry states that restorations should be placed with the best marginal quality possible to avoid postoperative sensitivity, marginal discoloration, and secondary caries. Different laboratory methods claim to predict the clinical performance of restorative materials, for example, tests of bond strength and microleakage and gap analysis. The purpose of this review was twofold: (1) find studies that correlated the results of bond strength tests with either microleakage or gap analysis for the same materials, and (2) find studies that correlated the results of microleakage and/or gaps with the clinical parameters for the same materials. Furthermore, influencing factors on the results of the laboratory tests were reviewed and assessed. For the first question, searches for studies were conducted in the MEDLINE database and IADR/AADR abtracts online with specific search and inclusion criteria. The outcome for each study was assessed on the basis of the statistical test applied in the study, and finally the number of studies with or without correlation was compiled. For the second question, results of the quantitative marginal analysis of Class V restorations published by the University of Zürich with the same test protocol and prospective clinical trials were searched that investigated the same materials for at least 2 years in Class V cavities. Pearson correlation coefficients were calculated for pooled data of materials and clinical outcome parameters such as retention loss, marginal discoloration, marginal integrity, and secondary caries. For the correlation of dye penetration and clinical outcome, studies on Class V restorations published by the same research institute were searched in MEDLINE that examined the same adhesive systems as the selected clinical trials. For the correlation bond strength/microleakage, 30 studies were included into the review, and for the correlation bond strength/gap analysis 18 studies. For both

Testing for marginal linear effects in quantile regression

KAUST Repository

Wang, Huixia Judy

2017-10-23

The paper develops a new marginal testing procedure to detect significant predictors that are associated with the conditional quantiles of a scalar response. The idea is to fit the marginal quantile regression on each predictor one at a time, and then to base the test on the t-statistics that are associated with the most predictive predictors. A resampling method is devised to calibrate this test statistic, which has non-regular limiting behaviour due to the selection of the most predictive variables. Asymptotic validity of the procedure is established in a general quantile regression setting in which the marginal quantile regression models can be misspecified. Even though a fixed dimension is assumed to derive the asymptotic results, the test proposed is applicable and computationally feasible for large dimensional predictors. The method is more flexible than existing marginal screening test methods based on mean regression and has the added advantage of being robust against outliers in the response. The approach is illustrated by using an application to a human immunodeficiency virus drug resistance data set.

Testing for marginal linear effects in quantile regression

KAUST Repository

Wang, Huixia Judy; McKeague, Ian W.; Qian, Min

2017-01-01

The paper develops a new marginal testing procedure to detect significant predictors that are associated with the conditional quantiles of a scalar response. The idea is to fit the marginal quantile regression on each predictor one at a time, and then to base the test on the t-statistics that are associated with the most predictive predictors. A resampling method is devised to calibrate this test statistic, which has non-regular limiting behaviour due to the selection of the most predictive variables. Asymptotic validity of the procedure is established in a general quantile regression setting in which the marginal quantile regression models can be misspecified. Even though a fixed dimension is assumed to derive the asymptotic results, the test proposed is applicable and computationally feasible for large dimensional predictors. The method is more flexible than existing marginal screening test methods based on mean regression and has the added advantage of being robust against outliers in the response. The approach is illustrated by using an application to a human immunodeficiency virus drug resistance data set.

Preface: Biogeochemistry–ecosystem interaction on changing continental margins in the Anthropocene

Digital Repository Service at National Institute of Oceanography (India)

Liu, K-K.; Emeis, K.-C.; Levin, L.A.; Naqvi, S.W.A.; Roman, M.

and hypercapnia in upwelling systems • Interactions between natural and social sciences for better steward- ship of continental margins. It has long been acknowledged (e.g., Doney, 2010; Liu et al., 2010) that marine ecosystems on continental margins, including... and possibly manage margin ecosystems in a changing world. Effective governance of social–ecological systems on continental margins is key to reducing the pervasive over- exploitation, depletion and destruction of marine resources and http://dx.doi.org/10...

Criptosporidiose em paciente com espondilite anquilosante usando adalimumabe Cryptosporidiosis in a patient with ankylosing spondylitis treated with adalimumab

Directory of Open Access Journals (Sweden)

Fernando Augusto Chiuchetta

2010-06-01

Full Text Available A criptosporidiose é uma doença parasitária causada pelo protozoário Cryptosporidium sp. Observou-se um aumento no número de diagnósticos realizados nos últimos vinte anos, principalmente em pacientes que apresentam imunodeficiências como a síndrome da imunodeficiência humana adquirida e as imunodeficiências induzidas como em pacientes transplantados e nos que necessitam realizar hemodiálise frequentemente. Relata-se o caso de um jovem com espondilite anquilosante que, usando adalimumabe, apresentou diarreia devido à criptosporidiose.Cryptosporidiosis is a parasitic disease caused by a protozoan called Cryptosporidium sp. An increased number of diagnoses were made in the last 20 years, especially in patients with immunodeficiency like the acquired human immunodeficiency syndrome and induced immunodeficiency, such as in transplant patients and those who need frequent hemodialysis, has been observed. We report the case of a young patient with ankylosing spondylitis treated with adalimumab who developed chronic diarrhea secondary to cryptosporidiosis

Assessment of bioenergy potential on marginal land in China

Energy Technology Data Exchange (ETDEWEB)

Zhuang, Dafang; Jiang, Dong; Liu, Lei; Huang, Yaohuan [Data Center for Resources and Environmental Sciences, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 11A Datun Road, Chaoyang District, Beijing 100101 (China)

2011-02-15

Bioenergy developed from energy plants will play a more and more important role in future energy supply. Much attention has been paid to energy plants in recent years. As China has fairly limited cultivated land resources, the bioenergy development may mainly rely on the exploitation of marginal land. This study focused on the assessment of marginal land resources and bio-fuel potential in China using newly acquired data and Geographic Information System (GIS) techniques. A multi-factor analysis method was adopted to identify marginal lands for bioenergy development in China, with data of several main types of energy plants on the eco-environmental requirements and natural habits employed. A combined planting zonation strategy was proposed, which was targeted for five species of energy plants including Helianthus tuberous L., Pistacia chinensis, Jatropha curcas L., Cassava and Vernicia fordii. The results indicated that total area of marginal land exploitable for development of energy plants on a large scale was about 43.75 million ha. If 10% of this marginal land was fully utilized for growing the energy plants, the production of bio-fuel would be 13.39 million tons. (author)

Relief for marginal wells is better than energy tax

International Nuclear Information System (INIS)

Swords, J.; Wilson, D.

1993-01-01

By increasing production costs and reducing petroleum prices, President Bill Clinton's proposed energy tax would increase marginal well abandonments and hasten the decline of the US oil and gas industry. Instead, the US needs tax law changes to help counteract the increasing number of oil and gas well abandonments in the lower 48 states. The proposed tax would create potential difficulties, while three incentives could be introduced to reduce abandonments and at the same time preserve US government tax revenues that otherwise would be lost. Eliminating the net income limitation on percentage depletion allowances on wells that would otherwise be abandoned would be a great help for marginal well operators. Extended enhanced oil recovery (EOR) credits and broader investment tax credits could also serve the dual purpose of keeping marginal wells operating longer and generating more federal tax revenues. A marginal well investment tax credit should be provided that is not just a credit for incremented investments that exceed investment in prior years. An investment tax credit based on out-of-pocket costs of production, targeted for marginal wells, would be an important incentive to invest in, and continue to maintain, these properties. (author)

In silico particle margination in blood flow

OpenAIRE

Müller, Kathrin

2015-01-01

A profound knowledge of margination, the migration of blood components to the vessel wall in blood flow, is required in order to understand the genesis of various diseases, as e.g., cardiovascular diseases or bleeding disorders. Margination of particles is a pre-condition for potential adhesion. Adhesion to the vessel wall is required for platelets, the protein von Willebrand factor (VWF), but also for drug and imaging agent carriers in order to perform their particular tasks. In the haemosta...

Medición de microdeformaciones en losas viales usando sensores de redes de Braggen fibras ópticas Microdeformation measurement of concrete roadway slabs using fiber Bragg gratings

Directory of Open Access Journals (Sweden)

Francisco Javier Vélez Hoyos

2010-06-01

Full Text Available En este trabajo se presenta un método no invasivo para la medición de microdeformaciones en estructuras de concreto usando sensores de redes de Bragg en fibras ópticas adheridos a su superficie. Se realizan mediciones en losas viales de concreto bajo una carga estática de 10 kN, encontrándose una relación aproximada de 2 : 1 entre la deformación registrada por los sensores y los valores arrojados por una simulación computacional con el método de elementos finitos. Se propone el uso de estos sensores para el monitoreo estructural de losas en una malla vial con sensores distribuidos y multiplexados por longitud de onda. Este es el primer reporte en Colombia de medición de deformación de losas viales usando sensores de fibra óptica.This work shows a non–invasive method for micro–deformation measurements of concrete structures using Bragg grating sensors in optical fibers adhered to the surface. Measurements on roadway slabs under a 10 kN static load are made, finding an approximated ratio of 2 : 1 between the deformation registered by the sensors and the values from a computational simulation with the finite element method. We propose the use of these sensors for slab structural monitoring in a road network employing distributed and wavelength multiplexed sensors. This is a first report in Colombia of roadway slabs microdeformation measurement using fiber optic sensors.

Seaward dipping reflectors along the SW continental margin of India: Evidence for volcanic passive margin

Digital Repository Service at National Institute of Oceanography (India)

Ajay, K.K.; Chaubey, A.K.; Krishna, K.S.; Rao, D.G.; Sar, D.

Multi-channel seismic reflection profiles across the southwest continental margin of India (SWCMI) show presence of westerly dipping seismic reflectors beneath sedimentary strata along the western flank of the Laccadive Ridge-northernmost part...

Marginalization and School Nursing

Science.gov (United States)

Smith, Julia Ann

2004-01-01

The concept of marginalization was first analyzed by nursing researchers Hall, Stevens, and Meleis. Although nursing literature frequently refers to this concept when addressing "at risk" groups such as the homeless, gays and lesbians, and those infected with HIV/AIDS, the concept can also be applied to nursing. Analysis of current school nursing…

Margins for geometric uncertainty around organs at risk in radiotherapy

International Nuclear Information System (INIS)

McKenzie, Alan; Herk, Marcel van; Mijnheer, Ben

2002-01-01

Background and purpose: ICRU Report 62 suggests drawing margins around organs at risk (ORs) to produce planning organ at risk volumes (PRVs) to account for geometric uncertainty in the radiotherapy treatment process. This paper proposes an algorithm for drawing such margins, and compares the recommended margin widths with examples from clinical practice and discusses the limitations of the approach. Method: The use of the PRV defined in this way is that, despite the geometric uncertainties, the dose calculated within the PRV by the treatment planning system can be used to represent the dose in the OR with a certain confidence level. A suitable level is where, in the majority of cases (90%), the dose-volume histogram of the PRV will not under-represent the high-dose components in the OR. In order to provide guidelines on how to do this in clinical practice, this paper distinguishes types of OR in terms of the tolerance doses relative to the prescription dose and suggests appropriate margins for serial-structure and parallel-structure ORs. Results: In some instances of large and parallel ORs, the clinician may judge that the complication risk in omitting a margin is acceptable. Otherwise, for all types of OR, systematic, treatment preparation uncertainties may be accommodated by an OR→PRV margin width of 1.3Σ. Here, Σ is the standard deviation of the combined systematic (treatment preparation) uncertainties. In the case of serial ORs or small, parallel ORs, the effects of blurring caused by daily treatment execution errors (set-up and organ motion) should be taken into account. Near a region of high dose, blurring tends to shift the isodoses away from the unblurred edge as shown on the treatment planning system by an amount that may be represented by 0.5σ. This margin may be used either to increase or to decrease the margin already calculated for systematic uncertainties, depending upon the size of the tolerance dose relative to the detailed planned dose

PORTRAIT GRAFFITI IN MARGINS OF ANTIQUE LITHUANIAN BOOKS

Directory of Open Access Journals (Sweden)

Burba, Domininkas

2006-12-01

Full Text Available This article presents and discusses fourteen drawings that portray a human and were found in manuscripts and printed books (documents that were actively used in Lithuania from 17th to 19th centuries. All the drawings were made in the margins of the documents. For the authors the drawings were not planned work but more like quips, scribbles and doodles. Therefore the terms portrait graffiti and (as a synonym portrait marginalia are used to describe the discussed portraits. According to the formal classification of marginal drawings (suggested by J. Liskeviciene two of the examined marginal portraits (no. 10 and 14 are classed as seperate and finished works with their own composition; ten marginal portraits (no. 2, 4, 5, 6, 7, 8, 9, 11, 12 and 13 represent the readers (document users sketch like drawings. Two other portraits (no. 1 and 3 are just scribbles that have nothing to do with artictic perception and are very close to book graffiti. From the artistic approcah the most sophisticated of the marginal portraits are “the hunt scene” (no. 14 and the late (first half of the 19th century “portrait of the teacher” (no. 13. In the viewpoint of documentary and social communication the discussed marginal drawings did not have a direct addressee. They were made not for public but for personal use. Paleographical, structural and content analysis of the document showed that the author of the “bearded nobleman” portrait (no. 2 could have been the elder of Merkine Antanas Kazimieras Sapiega. The political realia of Grand Duchy of Lithuania (from now GDL are reflected by the heart shaped portrait of a youngster who we can guess is portrayed weeping over the countries misfortunes and internal disagreements duringthe period of foreight military interventions in the years from 1733 to 1736. It was forbiden for scribes to daub on court files and other official GDL documents therefore the discussed graffiti could be linked to psychological stress and

Application of matrix singular value properties for evaluating gain and phase margins of multiloop systems. [stability margins for wing flutter suppression and drone lateral attitude control

Science.gov (United States)

Mukhopadhyay, V.; Newsom, J. R.

1982-01-01

A stability margin evaluation method in terms of simultaneous gain and phase changes in all loops of a multiloop system is presented. A universal gain-phase margin evaluation diagram is constructed by generalizing an existing method using matrix singular value properties. Using this diagram and computing the minimum singular value of the system return difference matrix over the operating frequency range, regions of guaranteed stability margins can be obtained. Singular values are computed for a wing flutter suppression and a drone lateral attitude control problem. The numerical results indicate that this method predicts quite conservative stability margins. In the second example if the eigenvalue magnitude is used instead of the singular value, as a measure of nearness to singularity, more realistic stability margins are obtained. However, this relaxed measure generally cannot guarantee global stability.

Small cell lymphocytic variant of marginal zone lymphoma: A distinct form of marginal zone lymphoma derived from naïve B cells as a cutaneous counterpart to the naïve marginal zone lymphoma of splenic origin.

Science.gov (United States)

Magro, Cynthia M; Olson, Luke C

2018-02-21

Primary cutaneous marginal zone lymphoma most commonly represents an indolent form of cutaneous B cell lymphoma. However, epidermotropic marginal zone lymphoma, blastic marginal zone lymphoma and B cell dominant variants without isotype switching can be associated with extracutaneous dissemination. The presumptive cell of origin is a post germinal center B cell with plasmacytic features. In the extracutaneous setting, however, a naïve B cell origin has been proposed for a subset of marginal zone lymphomas, notably splenic marginal zone lymphoma. The author encountered 11 cases of atypical lymphocytic infiltration of the skin primarily occurring in older individuals with an upper arm and head and neck localization; there was a reproducible pattern of diffuse and nodular infiltration by small monomorphic-appearing B cells. Phenotypically, the infiltrate was one predominated by B cells exhibiting CD23 and IgD positivity without immunoreactivity for CD38 and there were either no plasma cells or only a few without light chain restriction. In cases presenting with a solitary lesion complete excision and/or radiation led to successful disease remission in all cases without recurrence or metastatic disease. Of three cases with multiple initial lesions, evidence of extracutaneous disease was seen in two cases and recurrence occurred in one case. No patients have died of lymphoma. Longer term follows up and additional cases are needed to determine if this subset of marginal zone lymphoma is associated with a worse prognosis. Copyright © 2018. Published by Elsevier Inc.

Seismic safety margins research program overview

International Nuclear Information System (INIS)

Tokarz, F.J.; Smith, P.D.

1978-01-01

A multiyear seismic research program has been initiated at the Lawrence Livermore Laboratory. This program, the Seismic Safety Margins Research Program (SSMRP) is funded by the U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research. The program is designed to develop a probabilistic systems methodology for determining the seismic safety margins of nuclear power plants. Phase I, extending some 22 months, began in July 1978 at a funding level of approximately $4.3 million. Here we present an overview of the SSMRP. Included are discussions on the program objective, the approach to meet the program goal and objectives, end products, the probabilistic systems methodology, and planned activities for Phase I

Marketing margins and agricultural technology in Mozambique

DEFF Research Database (Denmark)

Arndt, Channing; Jensen, Henning Tarp; Robinson, Sherman

2000-01-01

of improved agricultural technology and lower marketing margins yield welfare gains across the economy. In addition, a combined scenario reveals significant synergy effects, as gains exceed the sum of gains from the individual scenarios. Relative welfare improvements are higher for poor rural households......Improvements in agricultural productivity and reductions in marketing costs in Mozambique are analysed using a computable general equilibrium (CGE) model. The model incorporates detailed marketing margins and separates household demand for marketed and home-produced goods. Individual simulations...

New evidence on the asymmetry in gasoline price: volatility versus margin?

International Nuclear Information System (INIS)

Abosedra, S.; Radchenko, S.

2006-01-01

This paper examines recent evidence on the role that gasoline margins and volatility play in the asymmetric response of gasoline prices to changes in oil prices at different stages of distribution process. In a regression model with margins, we find that margins are statistically significant in explaining asymmetry between crude oil and spot gasoline prices, spot gasoline prices and wholesale gasoline prices, and wholesale gasoline prices and retail prices. In a regression model with input volatility, we find evidence that volatility is responsible for asymmetry between wholesale gasoline prices and retail gasoline prices. When both, gasoline margins and gasoline volatility are included in the regression, we find evidence supporting margins, the search theory, volatility, the oligopolistic coordination theory and an explanation of asymmetry. (author)

Interpreting Marginal Effects in the Multinomial Logit Model

DEFF Research Database (Denmark)

Wulff, Jesper

2014-01-01

with a substantial increase in the probability of entering a foreign market using a joint venture, while increases in the unpredictability in the host country environment are associated with a lower probability of wholly owned subsidiaries and a higher probability of exporting entries....... that have entered foreign markets. Through the application of a multinomial logit model, careful analysis of the marginal effects is performed through graphical representations, marginal effects at the mean, average marginal effects and elasticities. I show that increasing cultural distance is associated......This paper presents the challenges when researchers interpret results about relationships between variables from discrete choice models with multiple outcomes. The recommended approach is demonstrated by testing predictions from transaction cost theory on a sample of 246 Scandinavian firms...

The Effects of Marginal Deviations on Behavioral Development.

Science.gov (United States)

Caprara, Gian Vittorio; Dodge, Kenneth A; Pastorelli, Concetta; Zelli, Arnaldo

2006-01-01

This investigation was conceptually framed within the theory of marginal deviations (Caprara & Zimbardo, 1996) and sought evidence for the general hypothesis that some children who initially show marginal behavioral problems may, over time, develop more serious problems depending partly on other personal and behavioral characteristics. To this end, the findings of two studies conducted, respectively, with American elementary school children and Italian middle school students are reviewed. These two studies show that hyperactivity, cognitive difficulties, low special preference, and lack of prosocial behavior increase a child's risk for growth in aggressive behavior over several school years. More importantly, they also show that equivalent levels of these risk factors have a greater impact on the development of children who, early on, were marginally aggressive.

Calculating the marginal costs of a district-heating utility

International Nuclear Information System (INIS)

Sjoedin, Joergen; Henning, Dag

2004-01-01

District heating plays an important role in the Swedish heat-market. At the same time, the price of district heating varies considerably among different district-heating utilities. A case study is performed here in which a Swedish utility is analysed using three different methods for calculating the marginal costs of heat supply: a manual spreadsheet method, an optimising linear-programming model, and a least-cost dispatch simulation model. Calculated marginal-costs, obtained with the three methods, turn out to be similar. The calculated marginal-costs are also compared to the actual heat tariff in use by the utility. Using prices based on marginal costs should be able to bring about an efficient resource-allocation. It is found that the fixed rate the utility uses today should be replaced by a time-of-use rate, which would give a more accurate signal for customers to change their heat consumptions. (Author)

Containment safety margins

International Nuclear Information System (INIS)

Von Riesemann, W.A.

1980-01-01

Objective of the Containment Safety Margins program is the development and verification of methodologies which are capable of reliably predicting the ultimate load-carrying capability of light water reactor containment structures under accident and severe environments. The program was initiated in June 1980 at Sandia and this paper addresses the first phase of the program which is essentially a planning effort. Brief comments are made about the second phase, which will involve testing of containment models

Fission product margin in burnup credit analyses

International Nuclear Information System (INIS)

Finck, P.J.; Stenberg, C.G.

1998-01-01

The US Department of Energy (DOE) is currently working toward the licensing of a methodology for using actinide-only burnup credit for the transportation of spent nuclear fuel (SNF). Important margins are built into this methodology. By using comparisons with a representative experimental database to determine bias factors, the methodology ensures that actinide concentrations and worths are estimated conservatively; furthermore, the negative net reactivity of certain actinides and all fission products (FPs) is not taken into account, thus providing additional margin. A future step of DOE's effort might aim at establishing an actinide and FP burnup credit methodology. The objective of this work is to establish the uncertainty to be applied to the total FP worth in SNF. This will serve two ends. First, it will support the current actinide-only methodology by demonstrating the margin available from FPs. Second, it will identify the major contributions to the uncertainty and help set priorities for future work

On marginally resolved objects in optical interferometry

Science.gov (United States)

Lachaume, R.

2003-03-01

With the present and soon-to-be breakthrough of optical interferometry, countless objects shall be within reach of interferometers; yet, most of them are expected to remain only marginally resolved with hectometric baselines. In this paper, we tackle the problem of deriving the properties of a marginally resolved object from its optical visibilities. We show that they depend on the moments of flux distribution of the object: centre, mean angular size, asymmetry, and curtosis. We also point out that the visibility amplitude is a second-order phenomenon, whereas the phase is a combination of a first-order term, giving the location of the photocentre, and a third-order term, more difficult to detect than the visibility amplitude, giving an asymmetry coefficient of the object. We then demonstrate that optical visibilities are not a good model constraint while the object stays marginally resolved, unless observations are carried out at different wavelengths. Finally, we show an application of this formalism to circumstellar discs.

OTIMIZAÇÃO USANDO ALGORITMO GENÉTICO DE UM MODELO DE PROPAGÇÃO BASEADO EM EQUAÇÕES PARABÓLICAS

Directory of Open Access Journals (Sweden)

Antonio Carlos Vilanova

2013-01-01

Full Text Available Este artigo apresenta uma avaliação metodológica para otimizar parâmetros em um conhecido modelo de propagação de ondas de rádio na troposfera. O modelo de propagação é baseado no Divisor de passos de Fourier para resolver equações parabólicas. Nossa abordagem utiliza algoritmo genético para determinar os valores dos parâmetros que maximize a intensidade de campo em uma determinada posição do observador. Usando algoritmo genético o tempo necessário na busca dos parâmetros ótimos é reduzido significativamente. A avaliação preliminar dos resultados através da simulação mostra que a nossa abordagem é promissora.

Lithosphere structure and subsidence evolution of the conjugate S-African and Argentine margins

Science.gov (United States)

Dressel, Ingo; Scheck-Wenderoth, Magdalena; Cacace, Mauro; Götze, Hans-Jürgen; Franke, Dieter

2016-04-01

The bathymetric evolution of the South Atlantic passive continental margins is a matter of debate. Though it is commonly accepted that passive margins experience thermal subsidence as a result of lithospheric cooling as well as load induced subsidence in response to sediment deposition it is disputed if the South Atlantic passive margins were affected by additional processes affecting the subsidence history after continental breakup. We present a subsidence analysis along the SW African margin and offshore Argentina and restore paleobathymetries to assess the subsidence evolution of the margin. These results are discussed with respect to mechanisms behind margin evolution. Therefore, we use available information about the lithosphere-scale present-day structural configuration of these margins as a starting point for the subsidence analysis. A multi 1D backward modelling method is applied to separate individual subsidence components such as the thermal- as well as the load induced subsidence and to restore paleobathymetries for the conjugate margins. The comparison of the restored paleobathymetries shows that the conjugate margins evolve differently: Continuous subsidence is obtained offshore Argentina whereas the subsidence history of the SW African margin is interrupted by phases of uplift. This differing results for both margins correlate also with different structural configurations of the subcrustal mantle. In the light of these results we discuss possible implications for uplift mechanisms.

Molecular markers in the surgical margin of oral carcinomas

DEFF Research Database (Denmark)

Bilde, A.; Buchwald, C. von; Dabelsteen, E.

2009-01-01

epithelium in the surgical resection margin may explain the local recurrence rate. The purpose of this study is to investigate the presence of senescence markers, which may represent early malignant changes in the margin that in routine pathological evaluations are classified as histologically normal...

Marginal Fit Comparison of CAD/CAM Crowns Milled from Two Different Materials.

Science.gov (United States)

Azarbal, Atousa; Azarbal, Mohsen; Engelmeier, Robert L; Kunkel, Thomas C

2017-11-16

To evaluate the marginal fit of CAD/CAM copings milled from hybrid ceramic (Vita Enamic) blocks and lithium disilicate (IPS e.max CAD) blocks, and to evaluate the effect of crystallization firing on the marginal fit of lithium disilicate copings. A standardized metal die with a 1-mm-wide shoulder finish line was imaged using the CEREC AC Bluecam. The coping was designed using CEREC 3 software. The design was used to fabricate 15 lithium disilicate and 15 hybrid ceramic copings. Design and milling were accomplished by one operator. The copings were seated on the metal die using a pressure clamp with a uniform pressure of 5.5 lbs. A Macroview Microscope (14×) was used for direct viewing of the marginal gap. Four areas were imaged on each coping (buccal, distal, lingual, mesial). Image analysis software was used to measure the marginal gaps in μm at 15 randomly selected points on each of the four surfaces. A total of 60 measurements were made per specimen. For lithium disilicate copings the measurements for marginal gap were made before and after crystallization firing. Data were analyzed using paired t-test and Kruskal-Wallis test. The overall mean difference in marginal gap between the hybrid ceramic and crystallized lithium disilicate copings was statistically significant (p marginal gaps were measured for crystallized lithium disilicate copings. The overall mean difference in marginal gap before and after firing (precrystallized and crystallized lithium disilicate copings) showed an average of 62 μm increase in marginal gap after firing. This difference was also significant (p marginal gap discrepancy when comparing hybrid ceramic and lithium disilicate CAD/CAM crowns. Also crystallization firing can result in a significant increase in the marginal gap of lithium disilicate CAD/CAM crowns. © 2017 by the American College of Prosthodontists.

Air-sea interactions in the marginal ice zone

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Seth Zippel

2016-03-01

Full Text Available Abstract The importance of waves in the Arctic Ocean has increased with the significant retreat of the seasonal sea-ice extent. Here, we use wind, wave, turbulence, and ice measurements to evaluate the response of the ocean surface to a given wind stress within the marginal ice zone, with a focus on the local wind input to waves and subsequent ocean surface turbulence. Observations are from the Beaufort Sea in the summer and early fall of 2014, with fractional ice cover of up to 50%. Observations showed strong damping and scattering of short waves, which, in turn, decreased the wind energy input to waves. Near-surface turbulent dissipation rates were also greatly reduced in partial ice cover. The reductions in waves and turbulence were balanced, suggesting that a wind-wave equilibrium is maintained in the marginal ice zone, though at levels much less than in open water. These results suggest that air-sea interactions are suppressed in the marginal ice zone relative to open ocean conditions at a given wind forcing, and this suppression may act as a feedback mechanism in expanding a persistent marginal ice zone throughout the Arctic.

Predicción de la generación interna volumétrica de calor y la capacidad calorífica durante un tratamiento electromagnético del material usando algoritmos híbridos

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Edgar García-Morantes

2018-01-01

Full Text Available Este trabajo considera la estimación de la generación interna volumétrica de calor y la capacidad calorífica de una muestra esférica sólida calentada por un campo electromagnético homogéneo variante en el tiempo. Para tal fin, la estrategia numérica soluciona el correspondiente problema inverso. Tres formas funcionales (lineal, senoidal y exponencial para el campo electromagnético fueron considerados. Ruido blanco fue agregado al perfil de temperatura teórica (i.e. la solución del problema directo para simular una situación más realística. La temperatura se pretendió que fuera leída por cuatro sensores. El problema inverso fue solucionado a través de tres diferentes enfoques: usando un optimizador tradicional, usando técnicas modernas y usando una mezcla de ambos. En el primer caso, usamos un algoritmo determinístico tradicional como lo es el de Levenberg-Marquardt (LM. En el segundo, consideramos tres metaheurísticos estocásticos: El Algoritmo de optimización de la espiral (SOA, la Búsqueda en vórtice (VS, y el método de atracción ponderada (WAM. Para el caso final, proponemos híbridos entre el LM y los algoritmos metahehurísticos. Los resultados muestran que LM converge a la solución esperada solo si las condiciones iniciales (IC están dentro de un rango limitado. Por otra parte, los metaheurísticos convergen en un amplio rango de IC pero muestra baja precisión. Los enfoques híbridos convergen y mejoran la precisión obtenida con los metaheurísticos. La diferencia entre los valores esperados y obtenidos, así como, los errores RMS son reportados y comparados para los tres métodos.

Dopamine reward prediction error responses reflect marginal utility.

Science.gov (United States)

Stauffer, William R; Lak, Armin; Schultz, Wolfram

2014-11-03

Optimal choices require an accurate neuronal representation of economic value. In economics, utility functions are mathematical representations of subjective value that can be constructed from choices under risk. Utility usually exhibits a nonlinear relationship to physical reward value that corresponds to risk attitudes and reflects the increasing or decreasing marginal utility obtained with each additional unit of reward. Accordingly, neuronal reward responses coding utility should robustly reflect this nonlinearity. In two monkeys, we measured utility as a function of physical reward value from meaningful choices under risk (that adhered to first- and second-order stochastic dominance). The resulting nonlinear utility functions predicted the certainty equivalents for new gambles, indicating that the functions' shapes were meaningful. The monkeys were risk seeking (convex utility function) for low reward and risk avoiding (concave utility function) with higher amounts. Critically, the dopamine prediction error responses at the time of reward itself reflected the nonlinear utility functions measured at the time of choices. In particular, the reward response magnitude depended on the first derivative of the utility function and thus reflected the marginal utility. Furthermore, dopamine responses recorded outside of the task reflected the marginal utility of unpredicted reward. Accordingly, these responses were sufficient to train reinforcement learning models to predict the behaviorally defined expected utility of gambles. These data suggest a neuronal manifestation of marginal utility in dopamine neurons and indicate a common neuronal basis for fundamental explanatory constructs in animal learning theory (prediction error) and economic decision theory (marginal utility). Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Biological impact of geometric uncertainties: what margin is needed for intra-hepatic tumors?

International Nuclear Information System (INIS)

Kuo, Hsiang-Chi; Liu, Wen-Shan; Wu, Andrew; Mah, Dennis; Chuang, Keh-Shih; Hong, Linda; Yaparpalvi, Ravi; Guha, Chandan; Kalnicki, Shalom

2010-01-01

To evaluate and compare the biological impact on different proposed margin recipes for the same geometric uncertainties for intra-hepatic tumors with different tumor cell types or clinical stages. Three different margin recipes based on tumor motion were applied to sixteen IMRT plans with a total of twenty two intra-hepatic tumors. One recipe used the full amplitude of motion measured from patients to generate margins. A second used 70% of the full amplitude of motion, while the third had no margin for motion. The biological effects of geometric uncertainty in these three situations were evaluated with Equivalent Uniform Doses (EUD) for various survival fractions at 2 Gy (SF 2 ). There was no significant difference in the biological impact between the full motion margin and the 70% motion margin. Also, there was no significant difference between different tumor cell types. When the margin for motion was eliminated, the difference of the biological impact was significant among different cell types due to geometric uncertainties. Elimination of the motion margin requires dose escalation to compensate for the biological dose reduction due to the geometric misses during treatment. Both patient-based margins of full motion and of 70% motion are sufficient to prevent serious dosimetric error. Clinical implementation of margin reduction should consider the tumor sensitivity to radiation

Avaliação da capacidade resistente última de estacas em compressão usando análises em tensão/deformação

OpenAIRE

Vieira, Ana Rita Ribeiro

2013-01-01

Dissertação para obtenção do Grau de Mestre em Engenharia Civil - Ramo de Estruturas e Geotecnia Nesta dissertação avalia-se a capacidade resistente última de estacas em compressão usando análises em tensão/deformação. A capacidade resistente última das estacas é avaliada através do programa computacional de elementos finitos Plaxis 2D v. 8 e é comparada com a capacidade resistente última prevista por métodos de extrapolação da curva carga vs. assetamento de ensaios de carga que não ...

Regrounding in Place: Paths to Native American Truths at the Margins

Science.gov (United States)

Lucas, Michael

2013-01-01

Margin acts as ground to receive the figure of the text. Margin is initially unreadable, but as suggested by gestalt studies, may be reversed, or regrounded. A humanities course, "Native American Architecture and Place," was created for a polytechnic student population, looking to place as an inroad for access to the margins of a better…

IDENTIFICACIÓN EFICIENTE DE ERRORES EN ESTIMACIÓN DE ESTADO USANDO UN ALGORITMO GENÉTICO ESPECIALIZADO IDENTIFICAÇÃO EFICAZ DOS ERROS EM ESTIMATIVA DE ESTADO USANDO UM ALGORITMO GENÉTICO ESPECIALIZADO EFFICIENT IDENTIFICATION OF ERRORS IN STATE ESTIMATION THROUGH A SPECIALIZED GENETIC ALGORITHM

Directory of Open Access Journals (Sweden)

Hugo Andrés Ruiz

2012-06-01

Full Text Available En este artículo se presenta un método para resolver el problema de estimación de estado en sistemas eléctricos usando optimización combinatoria. Su objetivo es el estudio de mediciones con errores de difícil detección, que afectan el desempeño y calidad de los resultados cuando se emplea un estimador de estado clásico. Dada su complejidad matemática, se deducen indicadores de sensibilidad de la teoría de puntos de apalancamiento que se usan en el algoritmo de optimización de Chu-Beasley, con el fin de disminuir el esfuerzo computacional y mejorar la calidad de los resultados. El método propuesto se valida en un sistema IEEE de 30 nodos.Neste artigo apresenta-se um método para resolver o problema de estimativa de estado em sistemas elétricos usando otimização combinatória. Seu objetivo é o estudo de medidas com erros de difícil detecção, que afetam o desempenho e qualidade dos resultados quando se emprega um estimador de estado clássico. Dada sua complexidade matemática, deduzem-se indicadores de sensibilidade da teoria de pontos de alavancagem que se usam no algoritmo de otimização de Chu-Beasley, com o fim de diminuir o esforço computacional e melhorar a qualidade dos resultados. O método proposto se valida em um sistema IEEE de 30 nós.In this paper a method to solve the state estimation problem in electric systems applying combinatorial optimization is presented. Its objective is the study of measures with difficult detection errors, which affect the performance and quality of the results when a classic state estimator is used. Due to the mathematical complexity, sensibility indicators are deduced from the theory of leverage points used in the Chu-Beasley optimization algorithm with the purpose of reducing the computational effort and enhance the quality of the results. The proposed method is validated in a 30-node IEEE system.

Safety margins in older adults increase with improved control of a dynamic object

Science.gov (United States)

Hasson, Christopher J.; Sternad, Dagmar

2014-01-01

Older adults face decreasing motor capabilities due to pervasive neuromuscular degradations. As a consequence, errors in movement control increase. Thus, older individuals should maintain larger safety margins than younger adults. While this has been shown for object manipulation tasks, several reports on whole-body activities, such as posture and locomotion, demonstrate age-related reductions in safety margins. This is despite increased costs for control errors, such as a fall. We posit that this paradox could be explained by the dynamic challenge presented by the body or also an external object, and that age-related reductions in safety margins are in part due to a decreased ability to control dynamics. To test this conjecture we used a virtual ball-in-cup task that had challenging dynamics, yet afforded an explicit rendering of the physics and safety margin. The hypotheses were: (1) When manipulating an object with challenging dynamics, older adults have smaller safety margins than younger adults. (2) Older adults increase their safety margins with practice. Nine young and 10 healthy older adults practiced moving the virtual ball-in-cup to a target location in exactly 2 s. The accuracy and precision of the timing error quantified skill, and the ball energy relative to an escape threshold quantified the safety margin. Compared to the young adults, older adults had increased timing errors, greater variability, and decreased safety margins. With practice, both young and older adults improved their ability to control the object with decreased timing errors and variability, and increased their safety margins. These results suggest that safety margins are related to the ability to control dynamics, and may explain why in tasks with simple dynamics older adults use adequate safety margins, but in more complex tasks, safety margins may be inadequate. Further, the results indicate that task-specific training may improve safety margins in older adults. PMID:25071566

Safety Margins in Older Adults Increase with Improved Control of a Dynamic Object

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Christopher James Hasson

2014-07-01

Full Text Available Older adults face decreasing motor capabilities due to pervasive neuromuscular degradations. As a consequence errors in movement control increase. Thus, older individuals should maintain larger safety margins than younger adults. While this has been shown for object manipulation tasks, several reports on whole-body activities, such as posture and locomotion, however demonstrate age-related reductions in safety margins. This is despite increased costs for control errors, such as a fall. We posit that this paradox could be explained by the dynamic challenge presented by the body or an external object, and that age-related reductions in safety margins are in part due to a decreased ability to control dynamics. To test this conjecture we used a virtual ball-in-cup task that had challenging dynamics, yet afforded an explicit rendering of the physics and safety margin. The hypotheses were: 1 When manipulating an object with challenging dynamics, older adults have smaller safety margins than younger adults. 2 Older adults increase their safety margins with practice. Nine young and 10 healthy older adults practiced moving the virtual ball-in-cup to a target location in exactly two seconds. The accuracy and precision of the timing error quantified skill and the ball energy relative to an escape threshold quantified the safety margin. Compared to the young adults, older adults had increased timing errors, greater variability, and decreased safety margins. With practice, both young and older adults improved their ability to control the object with decreased timing errors and variability, and increased their safety margins. These results suggest that safety margins are related to the ability to control dynamics, and may explain why in tasks with simple dynamics older adults use adequate safety margins, but in more complex tasks, safety margins may be inadequate. Further, the results indicate that task-specific training may improve safety margins in older

Texas curve margin of safety.

Science.gov (United States)

2013-01-01

This software can be used to assist with the assessment of margin of safety for a horizontal curve. It is intended for use by engineers and technicians responsible for safety analysis or management of rural highway pavement or traffic control devices...

Marginality and Social Rejection in Amiri Baraka's Slave Ship

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Hamid Hammad Abed

2016-11-01

Full Text Available Marginality and social rejection are the most influential matters exploited by Baraka to intentionally criticize the American society.  More often than not, these two matters have become the scenes of major or minor acts of humiliation and dehumanization that threaten to violate the ethical rules of living. This paper aims at investigating the impact of marginality and social rejection on a number of black characters in Baraka's Slave Ship who are brought to America to be sold as commodities. It is divided into two sections and conclusion. Section one deals with Amiri Baraka’s dramatic thought and experience of marginality within the American society. The textual analysis of Slave Ship is investigated in section two. The significance of the study lies in its textual exploration of the impact of marginality and social rejection in subverting the American dream of democracy, freedom, and equality in Baraka’s Slave Ship.

Marginal Bone Loss after Ten Years in an Adult Danish Population: A Radiographic Study.

Science.gov (United States)

Bahrami, Golnosh; Vaeth, Michael; Wenzel, Ann; Isidor, Flemming

To evaluate marginal bone loss over a 10-year period in individuals and in tooth groups in relation to age and level of marginal bone. In 1997, 616 randomly selected individuals (mean age: 42 years, range: 21-63 years) underwent a full-mouth radiographic survey. In 2008, the survey was repeated in 362 of the same individuals (182 women and 180 men). The marginal bone level of each tooth was measured in mm from the cementoenamel junction to the marginal bone. These measurements were used to calculate marginal bone loss during the 10-year period for individuals and tooth groups in relation to age and to baseline marginal bone level, calculated as the average between measurements in 1997 and 2008 to circumvent regression towards the mean. The average annual marginal bone loss was 0.09 mm (SD ± 0.04 mm) during the 10-year study period. The association between marginal bone loss and baseline marginal bone level was more pronounced in the youngest age group, compared to the other age groups. Molars displayed the most severe bone loss during the study period. Marginal bone loss over a 10-year period is associated with age and baseline marginal bone level. Younger individuals with a reduced marginal bone level were at higher risk for further bone loss. Molars lose marginal bone more rapidly than other tooth groups.

The role of the margins in ice stream dynamics

Science.gov (United States)

Echelmeyer, Keith; Harrison, William

1993-07-01

At first glance, it would appear that the bed of the active ice stream plays a much more important role in the overall force balance than do the margins, especially because the ratio of the half-width to depth for a typical ice stream is large (15:1 to 50:1). On the other hand, recent observations indicate that at least part of the ice stream is underlain by a layer of very weak till (shear strength about 2 kPa), and this weak basal layer would then imply that some or all of the resistive drag is transferred to the margins. In order to address this question, a detailed velocity profile near Upstream B Camp, which extends from the center of the ice stream, across the chaotic shear margin, and onto the Unicorn, which is part of the slow-moving ice sheet was measured. Comparison of this observed velocity profile with finite-element models of flow shows several interesting features. First, the shear stress at the margin is on the order of 130 kPa, while the mean value along the bed is about 15 kPa. Integration of these stresses along the boundaries indicates that the margins provide 40 to 50 percent, and the bed, 60 to 40 percent of the total resistive drag needed to balance the gravitational driving stress in this region. (The range of values represents calculations for different values of surface slope.) Second, the mean basal stress predicted by the models shows that the entire bed cannot be blanketed by the weak till observed beneath upstream B - instead there must be a distribution of weak till and 'sticky spots' (e.g., 85 percent till and 15 percent sticky spots of resistive stress equal to 100 kPa). If more of the bed were composed of weak till, then the modeled velocity would not match that observed. Third, the ice must exhibit an increasing enhancement factor as the margins are approached (E equals 10 in the chaotic zone), in keeping with laboratory measurements on ice under prolonged shear strain. Also, there is either a narrow zone of somewhat stiffer ice (E

Participatory democracy and Hillary Clinton’s marginalized fandom

Directory of Open Access Journals (Sweden)

Abigail De Kosnik

2008-09-01

Full Text Available After the drawn-out, heated contest for the Democratic Party presidential nomination and Senator Obama's victory over Senator Clinton, a segment of Clinton's supporters are threatening to leave the party rather than fall in line behind the nominee. This essay argues that the battle between Clinton's and Obama's followers is best understood as a war between fan bases, with Obama enthusiasts constituting as the dominant fandom and Clinton voters occupying the position of marginalized fandom. Marginalized fandoms tend to blame the opposing fan base, intermediaries, and The Powers That Be for their fan campaigns' losses, and Clinton's fans are adhering to this pattern. However, the Clinton marginalized fandom's complaints can be regarded as valuable critiques that, if noted rather than dismissed, could greatly strengthen participatory democracy in the United States.

Planning target volumes for radiotherapy: how much margin is needed?

International Nuclear Information System (INIS)

Antolak, John A.; Rosen, Isaac I.

1999-01-01

Purpose: The radiotherapy planning target volume (PTV) encloses the clinical target volume (CTV) with anisotropic margins to account for possible uncertainties in beam alignment, patient positioning, organ motion, and organ deformation. Ideally, the CTV-PTV margin should be determined solely by the magnitudes of the uncertainties involved. In practice, the clinician usually also considers doses to abutting healthy tissues when deciding on the size of the CTV-PTV margin. This study calculates the ideal size of the CTV-PTV margin when only physical position uncertainties are considered. Methods and Materials: The position of the CTV for any treatment is assumed to be described by independent Gaussian distributions in each of the three Cartesian directions. Three strategies for choosing a CTV-PTV margin are analyzed. The CTV-PTV margin can be based on: 1. the probability that the CTV is completely enclosed by the PTV; 2. the probability that the projection of the CTV in the beam's eye view (BEV) is completely enclosed by the projection of the PTV in the BEV; and 3. the probability that a point on the edge of the CTV is within the PTV. Cumulative probability distributions are derived for each of the above strategies. Results: Expansion of the CTV by 1 standard deviation (SD) in each direction results in the CTV being entirely enclosed within the PTV 24% of the time; the BEV projection of the CTV is enclosed within the BEV projection of the PTV 39% of the time; and a point on the edge of the CTV is within the PTV 84% of the time. To have the CTV enclosed entirely within the PTV 95% of the time requires a margin of 2.8 SD. For the BEV projection of the CTV to be within the BEV projection of the PTV 95% of the time requires a margin of 2.45 SD. To have any point on the surface of the CTV be within the PTV 95% of the time requires a margin of 1.65 SD. Conclusion: In the first two strategies for selecting a margin, the probability of finding the CTV within the PTV is

Marginal Loss Calculations for the DCOPF

Energy Technology Data Exchange (ETDEWEB)

Eldridge, Brent [Federal Energy Regulatory Commission, Washington, DC (United States); Johns Hopkins Univ., Baltimore, MD (United States); O' Neill, Richard P. [Federal Energy Regulatory Commission, Washington, DC (United States); Castillo, Andrea R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-12-05

The purpose of this paper is to explain some aspects of including a marginal line loss approximation in the DCOPF. The DCOPF optimizes electric generator dispatch using simplified power flow physics. Since the standard assumptions in the DCOPF include a lossless network, a number of modifications have to be added to the model. Calculating marginal losses allows the DCOPF to optimize the location of power generation, so that generators that are closer to demand centers are relatively cheaper than remote generation. The problem formulations discussed in this paper will simplify many aspects of practical electric dispatch implementations in use today, but will include sufficient detail to demonstrate a few points with regard to the handling of losses.

Marginalism, quasi-marginalism and critical phenomena in micellar solutions

International Nuclear Information System (INIS)

Reatto, L.

1986-01-01

The observed nonuniversal critical behaviour of some micellar solutions is interpreted in terms of quasi-marginalism, i.e. the presence of a coupling which scales with an exponent very close to the spatial dimensionality. This can give rise to a preasymptotic region with varying effective critical exponents with a final crossover to the Ising ones. The reduced crossover temperature is estimated to be below 10 -6 . The exponents β and γ measured in C 12 e 5 are in good agreement with the scaling law expected to hold for the effective exponents. The model considered by Shnidman is found unable to explain the nonuniversal critical behaviour

Passive margins getting squeezed in the mantle convection vice

Science.gov (United States)

Yamato, Philippe; Husson, Laurent; Becker, Thorsten W.; Pedoja, Kevin

2014-05-01

Passive margins often exhibit uplift, exhumation and tectonic inversion. We speculate that the compression in the lithosphere gradually increased during the Cenozoic. In the same time, the many mountain belts at active margins that accompany this event seem readily witness this increase. However, how that compression increase affects passive margins remains unclear. In order to address this issue, we design a 2D viscous numerical model wherein a lithospheric plate rests above a weaker mantle. It is driven by a mantle conveyor belt, alternatively excited by a lateral downwelling on one side, an upwelling on the other side, or both simultaneously. The lateral edges of the plate are either free or fixed, representing the cases of free convergence, and collision or slab anchoring, respectively. This distinction changes the upper boundary condition for mantle circulation and, as a consequence, the stress field. Our results show that between these two regimes, the flow pattern transiently evolves from a free-slip convection mode towards a no-slip boundary condition above the upper mantle. In the second case, the lithosphere is highly stressed horizontally and deforms. For an equivalent bulk driving force, compression increases drastically at passive margins provided that upwellings are active. Conversely, if downwellings alone are activated, compression occurs at short distances from the trench and extension prevails elsewhere. These results are supported by Earth-like 3D spherical models that reveal the same pattern, where active upwellings are required to excite passive margins compression. These results support the idea that compression at passive margins, is the response to the underlying mantle flow, that is increasingly resisted by the Cenozoic collisions.

Pricing district heating by marginal cost

International Nuclear Information System (INIS)

Difs, Kristina; Trygg, Louise

2009-01-01

A vital measure for industries when redirecting the energy systems towards sustainability is conversion from electricity to district heating (DH). This conversion can be achieved for example, by replacing electrical heating with DH and compression cooling with heat-driven absorption cooling. Conversion to DH must, however, always be an economically attractive choice for an industry. In this paper the effects for industries and the local DH supplier are analysed when pricing DH by marginal cost in combination with industrial energy efficiency measures. Energy audits have shown that the analysed industries can reduce their annual electricity use by 30% and increase the use of DH by 56%. When marginal costs are applied as DH tariffs and the industrial energy efficiency measures are implemented, the industrial energy costs can be reduced by 17%. When implementing the industrial energy efficiency measures and also considering a utility investment in the local energy system, the local DH supplier has a potential to reduce the total energy system cost by 1.6 million EUR. Global carbon dioxide emissions can be reduced by 25,000 tonnes if the industrial energy efficiency measures are implemented and when coal-condensing power is assumed to be the marginal electricity source

Marginalized Student Access to Technology Education

Science.gov (United States)

Kurtcu, Wanda M.

The purpose of this paper is to investigate how a teacher can disrupt an established curriculum that continues the cycle of inequity of access to science, technology, engineering, and math (STEM) curriculum by students in alternative education. For this paper, I will focus on the technology components of the STEM curriculum. Technology in the United States, if not the world economy, is developing at a rapid pace. Many areas of day to day living, from applying for a job to checking one's bank account online, involve a component of science and technology. The 'gap' in technology education is emphasized between the 'haves and have-nots', which is delineated along socio-economic lines. Marginalized students in alternative education programs use this equipment for little else than remedial programs and credit recovery. This level of inequity further widens in alternative education programs and affects the achievement of marginalized students in credit recovery or alternative education classes instead of participation technology classes. For the purposes of this paper I focus on how can I decrease the inequity of student access to 21st century technology education in an alternative education program by addressing the established curriculum of the program and modifying structural barriers of marginalized student access to a technology focused curriculum.

Geomorphic response of a continental margin to tectonic and eustatic variations, the Levant margin during the Messinian Salinity Crisis

Science.gov (United States)

Ben Moshe, Liran; Ben-Avraham, Zvi; Enzel, Yehouda; Uri, Schattner

2017-04-01

During the Messinian Salinity Crisis (MSC, 5.97±0.01-5.33 Ma) the Mediterranean Levant margin experienced major eustatic and sedimentary cycles as well as tectonic motion along the nearby Dead Sea fault plate boundary. New structures formed along this margin with morphology responding to these changes. Our study focuses on changes in this morphology across the margin. It is based on interpretation of three 3D seismic reflection volumes from offshore Israel. Multi-attribute analysis aided the extraction of key reflectors. Morphologic analysis of these data quantified interacting eustasy, sedimentation, and tectonics. Late Messinian morphologic domains include: (a) continental shelf; (b) 'Delta' anticline, forming a ridge diagonal to the strike of the margin; (c) southward dipping 'Hadera' valley, separating between (a) and (b); (d) 'Delta Gap' - a water gap crossing perpendicular to the anticline axis, exhibiting a sinuous thalweg; (e) continental slope. Drainage across the margin developed in several stages. Remains of turbidite flows crossing the margin down-slope were spotted across the 'Delta' anticline. These flows accumulated with the MSC evaporate sequence and prior to the anticline folding. Rising of the anticline, above the then bathymetry, either blocked or diverted the turbidites. That rising also defined the Hadera valley. In-situ evaporates, covering the valley floor, are, in turn covered by a fan-delta at the distal end of the valley. The fan-delta complex contains eroded evaporites and Lago-Mare fauna. Its top is truncated by dendritic fluvial channels that drained towards the Delta Gap. The Delta Gap was carved through the Delta ridge in a morphological and structural transition zone. We propose that during the first stages of the MSC (5.97±0.01-5.59 ma) destabilization of the continental slope due to oscillating sea level produced gravity currents that flowed through the pre-existing Delta anticline. Subsequent folding of the Delta anticline

Deep continental margin reflectors

Science.gov (United States)

Ewing, J.; Heirtzler, J.; Purdy, M.; Klitgord, Kim D.

1985-01-01

In contrast to the rarity of such observations a decade ago, seismic reflecting and refracting horizons are now being observed to Moho depths under continental shelves in a number of places. These observations provide knowledge of the entire crustal thickness from the shoreline to the oceanic crust on passive margins and supplement Consortium for Continental Reflection Profiling (COCORP)-type measurements on land.

Estimate of DMFT index using teeth most affected by dental caries in twelve-year-old children Estimación del índice DMFT usando los dientes más afectados por caries dentales en niños de doce años Estimativa do Índice CPOD usando os dentes mais afetados pela cárie dentária aos doze anos

Directory of Open Access Journals (Sweden)

Stela Márcia Pereira

2009-02-01

Full Text Available The objective of the study was to develop regression models to describe the epidemiological profile of dental caries in 12-year-old children in an area of low prevalence of caries. Two distinct random probabilistic samples of schoolchildren (n=1,763 attending public and private schools in Piracicaba, Southeastern Brazil, were studied. Regression models were estimated as a function of the most affected teeth using data collected in 2005 and were validated using a 2001 database. The mean (SD DMFT index was 1.7 (2.08 in 2001 and the regression equations estimated a DMFT index of 1.67 (1.98, which corresponds to 98.2% of the DMFT index in 2001. The study provided detailed data on the caries profile in 12-year-old children by using an updated analytical approach. Regression models can be an accurate and feasible method that can provide valuable information for the planning and evaluation of oral health services.El objetivo de este estudio fue desarrollar modelos de regresión para describir el perfil epidemiológico de caries dentales en niños de 12 años en un área de baja prevalencia de caries. Fueron estudiados dos muestras distintas aleatorias y probabilísticas de niños escolares (n= 1.763 que estudiaban en colegios públicos y privados en Piracicaba, Sureste de Brasil. Modelos de regresión fueron estimados como una función de los dientes más afectados usando datos colectados en 2005 y fueron validados usando una base de datos del 2001. El índice promedio (SD de DMFT fue 1,7 (2,08 en 2001 y las ecuaciones de regresión estimaron un índice de DMFT de 1,67 (1,98, lo cual corresponde a 98,2% del índice en 2001. El estudio provee datos detallados sobre el perfil de caries en niños de 12 años usando una aproximación analítica. Los modelos de regresión pueden ser un método confiable y factible que puede proporcional información valiosa para la planificación y evaluación de servicios de cuidado oral.O objetivo do estudo foi

Perforated marginal ulcers after laparoscopic gastric bypass.

Science.gov (United States)

Felix, Edward L; Kettelle, John; Mobley, Elijah; Swartz, Daniel

2008-10-01

Perforated marginal ulcer (PMU) after laparoscopic Roux-en-Y gastric bypass (LRYGB) is a serious complication, but its incidence and etiology have rarely been investigated. Therefore, a retrospective review of all patients undergoing LRYGB at the authors' center was conducted to determine the incidence of PMU and whether any causative factors were present. A prospectively kept database of all patients at the authors' bariatric center was retrospectively reviewed. The complete records of patients with a PMU were examined individually for accuracy and analyzed for treatment, outcome, and possible underlying causes of the marginal perforation. Between April 1999 and August 2007, 1% of the patients (35/3,430) undergoing laparoscopic gastric bypass experienced one or more perforated marginal ulcers 3 to 70 months (median, 18 months) after LRYGB. The patients with and without perforation were not significantly different in terms of mean age (37 vs 41 years), weight (286 vs 287 lb), body mass index (BMI) (46 vs 47), or female gender (89% vs 83%). Of the patients with perforations, 2 (6%) were taking steroids, 10 (29%) were receiving nonsteroidal antiinflammatory drugs (NSAIDs) at the time of the perforation, 18 (51%) were actively smoking, and 6 of the smokers also were taking NSAIDs. Eleven of the patients (31%) who perforated did not have at least one of these possible risk factors, but 4 (36%) of the 11 patients in this group had been treated after bypass for a marginal ulcer. Only 7 (20%) of the 35 patients who had laparoscopic bypass, or 7 (0.2%) in the entire group of 3,430 patients, perforated without any warning. There were no deaths, but three patients reperforated. The incidence of a marginal ulcer perforating after LRYGB was significant (>1%) and appeared to be related to smoking or the use of NSAIDs or steroids. Because only 0.2% of all patients acutely perforated without some risk factor or warning, long-term ulcer prophylaxis or treatment may be necessary

Tiago Marques Aipobureu: um bororo marginal Tiago Marques Aipobureu: a Bororo on the margins

Directory of Open Access Journals (Sweden)

Florestan Fernandes

2007-11-01

Full Text Available O texto analisa a biografia de um membro da tribo dos Bororo, Tiago Marques Aipobureu, que, nascido no planalto oriental de Mato Grosso, foi levado pelos missionários para estudar em Cuiabá e depois viajou pela Europa. Quando de seu retorno ao Brasil, foi empregado como professor, mas não conseguiu adaptar-se à nova vida. Casado com uma mulher de sua tribo, buscou então reintegrar-se aos Bororo, igualmente sem sucesso. Permanecia, desse modo, no meio do caminho, incapaz de integrar-se plenamente tanto à sociedade e cultura "civilizadas" como à sociedade e cultura indígenas. O desajustamento de Tiago evidencia a situação do homem marginal, daquele que se situa na divisa de duas raças, na margem de duas culturas sem conseguir pertencer integralmente a nenhuma delas.The text analyzes the biography of a member of the Bororo tribe, Tiago Marques Aipobureu. Born on the eastern plateau of Mato Grosso, he was taken by missionaries to study in Cuiabá and later travelled through Europe. On returning to Brazil, he was employed as a teacher, but was unable to adapt to his new life. Married to a woman from his tribe, he tried to rejoin the Bororo, likewise without success. Thus he found himself midway between worlds, unable to join fully either 'civilized' society and culture, or indigenous society and culture. Tiago's maladjustment exemplifies the situation of the marginal person, someone situated on the dividing line between two races, on the margin of two cultures, unable to belong wholly to either.

Permian-Triassic Tethyan realm reorganization: Implications for the outward Pangea margin

Science.gov (United States)

Riel, Nicolas; Jaillard, Etienne; Martelat, Jean-Emmanuel; Guillot, Stéphane; Braun, Jean

2018-01-01

We present a new conceptual model to explain the first order Permian-Triassic evolution of the whole > 30 000 km long Pangea margin facing the Panthalassa ocean. Compilation of available geological, geochemical, geochronogical and paleomagnetic data all along this system allowed us to distinguish three part of the margin: western Laurentia, western Gondwana and eastern Gondwana. These segments record distinct tectonic and magmatic events, which all occur synchronously along the whole margin and correlate well with the main geodynamic events of this period, i.e. subduction of the Paleotethys mid-ocean ridge at 310-280 Ma, opening of the Neotethys at 280-260 Ma, counterclockwise rotation of Pangea at 260-230 Ma and closure of the Paleotethys at 230-220 Ma. Between 260 and 230 Ma, the reorganization of the Tethyan realm triggered the up to 35° rotation of Pangea around an Euler pole located in northernmost South America. This implied both an increase and a decrease of the convergence rate between the margin and the Panthalassa ocean, north and south of the Euler pole, respectively. Thus, the Permian-Triassic Pangean margin was marked: in western Laurentia by marginal sea closure, in western Gondwana by widespread bimodal magmatic and volcanic activity, in eastern Gondwana by transpressive orogenic phase. Therefore, we propose that the Permian-Triassic evolution of the outward margin of Pangea was controlled by the Tethyan realm reorganization.

Marginal pricing of transmission services. An analysis of cost recovery

Energy Technology Data Exchange (ETDEWEB)

Perez-Arriaga, I.J.., Rubio, F.J. [Instituto de Investigacion Technologica, Universidad Pontificia Comillas, Madrid (Spain); Puerta, J.F.; Arceluz, J.; Marin, J. [Unidad de Planificacion Estrategica, Iberdrola, Madrid (Spain)

1996-12-31

The authors present an in-depth analysis of network revenues that are computed with marginal pricing, and investigate the reasons why marginal prices in actual power systems fail to recover total incurred network costs. The major causes of the failure are identified and illustrated with numerical examples. The paper analyzes the regulatory implications of marginal network pricing in the context of competitive electricity markets and provides suggestions for the meaningful allocation of network costs among users. 5 figs., 9 tabs., 8 refs.

Marginal pricing of transmission services. An analysis of cost recovery

International Nuclear Information System (INIS)

Perez-Arriaga, I.J.., Rubio, F.J.; Puerta, J.F.; Arceluz, J.; Marin, J.

1996-01-01

The authors present an in-depth analysis of network revenues that are computed with marginal pricing, and investigate the reasons why marginal prices in actual power systems fail to recover total incurred network costs. The major causes of the failure are identified and illustrated with numerical examples. The paper analyzes the regulatory implications of marginal network pricing in the context of competitive electricity markets and provides suggestions for the meaningful allocation of network costs among users. 5 figs., 9 tabs., 8 refs

The origin of Karaj dam basement sill marginal reversal by Soret fractionation

Science.gov (United States)

Maghdour-Mashhour, Reza; Esmaeily, Dariush

2010-05-01

The Karaj dam basement sill (KDBS), located North West of Tehran, northern Iran, is one of the several E-W-trending plutons in the Albourz Mountains. The KDBS consists of a layered series between upper and lower chilled margins. The rocks of the chilled margins are gabbroic in composition and porphyritic, with euhedral to subhedral plagioclase and clinopyroxene megacrysts up to 5 mm long. The rocks become coarse-grained toward the center of the sill and show a gradual transition from porphyritic to equigranular texture. Field and petrographic observations reveal a reverse trend in marginal units crystallization from the eutectic point to the main magma composition; i.e., the olivine-bearing gabbro (porphyritic chilled margin), which has a eutectic composition, crystallized prior to the marginal gabbros, which have a cotectic or near-cotectic composition, as plagioclase laths in the gabbroic unit are embedded in large crystals of clinopyroxene and this phenomenon is believed to result from the cotectic crystallization of plagioclase and clinopyroxene. Four major mechanisms are proposed and discussed in order to find the exact mechanism responsible for marginal reversal formation as following: 1) Crystal settling is a gravity-dependent mechanism and phenocrysts must have settled to form a layer at the bottom of the sill, showing sharp upper boundary which is not observable in KDBS. Besides, the reverse fractionation of inwardly-dipping sequence of mentioned sill occurs in layers with primary dips up to 55°. Consequently capability of marginal reversals to develop along steeply inclined chamber margins, by this mechanism is implausible. 2) Multiple injections of successive magma pulses fails to explain the origin of marginal reversal since the transition along the entire length of marginal reversal is gradual also there is no compositional break or chilled contact between two mentioned units of KDBS margin (Olivine-gabbro and marginal gabbro). 3) The idea of

Diseño e implementación de una herramienta para analizar imágenes extraídas de redes sociales, usando la librería OpenCV

OpenAIRE

Ramos Alférez, Albert

2015-01-01

Diseño de una aplicación web que permite extraer información de redes sociales e internet para reconocimiento de personas desaparecidas Design and implementation of a tool for analyzing images taken from social networks, using the OpenCV library Diseño e implementación de una herramienta para analizar imágenes extraídas de redes sociales, usando la librería OpenCV Disseny e implementació d'una eina per analitzar imatges extretes de les xarxes socials, utilitzant la llibrería OpenCV...

Experimental validation of the van Herk margin formula for lung radiation therapy

International Nuclear Information System (INIS)

Ecclestone, Gillian; Heath, Emily; Bissonnette, Jean-Pierre

2013-01-01

Purpose: To validate the van Herk margin formula for lung radiation therapy using realistic dose calculation algorithms and respiratory motion modeling. The robustness of the margin formula against variations in lesion size, peak-to-peak motion amplitude, tissue density, treatment technique, and plan conformity was assessed, along with the margin formula assumption of a homogeneous dose distribution with perfect plan conformity.Methods: 3DCRT and IMRT lung treatment plans were generated within the ORBIT treatment planning platform (RaySearch Laboratories, Sweden) on 4DCT datasets of virtual phantoms. Random and systematic respiratory motion induced errors were simulated using deformable registration and dose accumulation tools available within ORBIT for simulated cases of varying lesion sizes, peak-to-peak motion amplitudes, tissue densities, and plan conformities. A detailed comparison between the margin formula dose profile model, the planned dose profiles, and penumbra widths was also conducted to test the assumptions of the margin formula. Finally, a correction to account for imperfect plan conformity was tested as well as a novel application of the margin formula that accounts for the patient-specific motion trajectory.Results: The van Herk margin formula ensured full clinical target volume coverage for all 3DCRT and IMRT plans of all conformities with the exception of small lesions in soft tissue. No dosimetric trends with respect to plan technique or lesion size were observed for the systematic and random error simulations. However, accumulated plans showed that plan conformity decreased with increasing tumor motion amplitude. When comparing dose profiles assumed in the margin formula model to the treatment plans, discrepancies in the low dose regions were observed for the random and systematic error simulations. However, the margin formula respected, in all experiments, the 95% dose coverage required for planning target volume (PTV) margin derivation, as

Energy system analysis of marginal electricity supply in consequential LCA

DEFF Research Database (Denmark)

Lund, Henrik; Mathiesen, Brian Vad; Christensen, Per

2010-01-01

Background, aim and scope This paper discusses the identification of the environmental consequences of marginal electricity supplies in consequential life cycle assessments (LCA). According to the methodology, environmental characteristics can be examined by identifying affected activities, i...... in capacity but can be characterised as a complex set of affected electricity and heat supply technologies. A long-term YAM technology is identified for the Danish BAU2030 system in the case of three different long-term marginal changes in capacity, namely coal, natural gas or wind power. Discussion Four...... of four different situations are provided. We suggest that the technology mix with the installation of natural gas or coal power plant is applied as the marginal capacity. Conclusions The environmental consequences of marginal changes in electricity supply cannot always be represented solely by long...

Can pro-marriage policies work? An analysis of marginal marriages.

Science.gov (United States)

Frimmel, Wolfgang; Halla, Martin; Winter-Ebmer, Rudolf

2014-08-01

Policies to promote marriage are controversial, and it is unclear whether they are successful. To analyze such policies, one must distinguish between a marriage that is created by a marriage-promoting policy (marginal marriage) and a marriage that would have been formed even in the absence of a state intervention (average marriage). We exploit the suspension of a cash-on-hand marriage subsidy in Austria to examine the differential behavior of marginal and average marriages. The announcement of an impending suspension of this subsidy led to an enormous marriage boom among eligible couples that allows us to locate marginal marriages. Applying a difference-in-differences approach, we show that marginal marriages are surprisingly as stable as average marriages but produce fewer children, children later in marriage, and children who are less healthy at birth.

Marginal Teachers from the Eyes of School Principals: Concept, Problems and Management Strategies

Science.gov (United States)

Erdogan, Cetin; Demirkasimoglu, Nihan

2016-01-01

This research aimed to determine how Turkish principals define marginal teachers and which strategies they use to deal with them. Within this purpose, the following points are examined: (a) the concept of marginal teacher, (b) the underlying reasons for marginal teacher behaviors, (c) the problems marginal teachers cause in school settings, (d)…

Seismic margin review of the Maine Yankee Atomic Power Station: Fragility analysis

International Nuclear Information System (INIS)

Ravindra, M.K.; Hardy, G.S.; Hashimoto, P.S.; Griffin, M.J.

1987-03-01

This Fragility Analysis is the third of three volumes for the Seismic Margin Review of the Maine Yankee Atomic Power Station. Volume 1 is the Summary Report of the first trial seismic margin review. Volume 2, Systems Analysis, documents the results of the systems screening for the review. The three volumes are part of the Seismic Margins Program initiated in 1984 by the Nuclear Regulatory Commission (NRC) to quantify seismic margins at nuclear power plants. The overall objectives of the trial review are to assess the seismic margins of a particular pressurized water reactor, and to test the adequacy of this review approach, quantification techniques, and guidelines for performing the review. Results from the trial review will be used to revise the seismic margin methodology and guidelines so that the NRC and industry can readily apply them to assess the inherent quantitative seismic capacity of nuclear power plants

Seismic margin review of the Maine Yankee Atomic Power Station: Fragility analysis

Energy Technology Data Exchange (ETDEWEB)

Ravindra, M. K.; Hardy, G. S.; Hashimoto, P. S.; Griffin, M. J.

1987-03-01

This Fragility Analysis is the third of three volumes for the Seismic Margin Review of the Maine Yankee Atomic Power Station. Volume 1 is the Summary Report of the first trial seismic margin review. Volume 2, Systems Analysis, documents the results of the systems screening for the review. The three volumes are part of the Seismic Margins Program initiated in 1984 by the Nuclear Regulatory Commission (NRC) to quantify seismic margins at nuclear power plants. The overall objectives of the trial review are to assess the seismic margins of a particular pressurized water reactor, and to test the adequacy of this review approach, quantification techniques, and guidelines for performing the review. Results from the trial review will be used to revise the seismic margin methodology and guidelines so that the NRC and industry can readily apply them to assess the inherent quantitative seismic capacity of nuclear power plants.

Tratamiento de enfermedad de aorta torácica con afectación de troncos supraaórticos usando técnica combinada de cirugía convencional y tratamiento endovascular

Directory of Open Access Journals (Sweden)

Antonio Jiménez Aceituno

2007-04-01

Conclusiones: El abordaje del arco aórtico usando técnicas endovasculares presenta el problema de la oclusión de TSA. El uso de derivaciones quirúrgicas hace posible esto. El abordaje combinado es aún una técnica nueva pero que podría ser una alternativa válida a la cirugía abierta de arco y aorta torácica descendente. Nuestra experiencia es satisfactoria, aunque no concluyente por tratarse sólo de dos casos.

Margin of Valuation Error Among Nigerian Valuers: Postulating an ...

African Journals Online (AJOL)

Study on margin of error aims at capturing the response of Nigerian valuers and their clients from the financial sector to their permissable margin of error with a view to establishing the bracket outside which the valuer is considered incompetent. The opinion of 300 Estate Surveyors and Valuers were sampled using simple ...

Ethnographies of marginality [Review article

NARCIS (Netherlands)

Beuving, J.J.

2016-01-01

Africanist discourse today displays a strong, widespread and growing sense of optimism about Africa's economic future. After decades of decline and stagnation in which Africa found itself reduced to the margins of the global economic stage, upbeat Afro-optimism seems fully justified. One only needs

Influence of abutment screw preload on stress distribution in marginal bone.

Science.gov (United States)

Khraisat, Ameen

2012-01-01

Changes in an implant assembly after abutment connection might possibly cause deformation in the implant/abutment joint and even in the marginal bone. The aim of this study was to evaluate the influence of abutment screw preload through the implant collar on marginal bone stress without external load application. Models of three implant parts made of titanium (implant, abutment, and abutment screw) and cortical bone were built and positioned with computer-aided design software. Meshing and generation of boundary conditions, loads, and interactions were performed. Each part was meshed independently. The sole load applied to the model was a torque of 32 Ncm on the abutment screw about its axis of rotation. The implant collar was deformed axially after the screw was tightened (3 μm). This deformation resulted in 60 MPa of stress in the marginal bone. Moreover, pressure on the marginal bone in a radial direction was observed. It can be concluded that, without any external load application, abutment screw preload exerts stresses on the implant collar and the marginal bone. These findings should help guide the development of new implant/abutment joint designs that exert less stress on the marginal bone.

A Longitudinal View of the Relationship Between Social Marginalization and Obesity

Science.gov (United States)

Apolloni, Andrea; Marathe, Achla; Pan, Zhengzheng

We use 3 Waves of the Add Health data collected between 1994 and 2002 to conduct a longitudinal study of the relationship between social marginalization and the weight status of adolescents and young adults. Past studies have shown that overweight and obese children are socially marginalized. This research tests (1) if this is true when we account for the sample size of each group, (2) does this phenomenon hold over time and (3) is it obesity or social marginalization that precedes in time. Our results show that when the sample size for each group is considered, the share of friendship is conforming to the size of the group. This conformity seems to increase over time as the population becomes more obese. Finally, we find that obesity precedes social marginalization which lends credence to the notion that obesity causes social marginalization and not vice versa.

A brief introduction to marginal analysis for the micro-economics principles course

OpenAIRE

Burkey, Mark L.

2008-01-01

This brief note provides a simple, yet powerful example of how the marginal cost/marginal benefit principle can be used in everyday life. Using the decision of the optimal choice of speed on the highway, this note was developed for use as one of the first readings in an introductory microeconomics course. It is clear in this demonstration that marginal cost is increasing, while marginal benefit is decreasing, and how the intersection of these two curves shows the optimal choice. In addition, ...

Role of specimen US for predicting resection margin status in breast conserving therapy.

Science.gov (United States)

Moschetta, M; Telegrafo, M; Introna, T; Coi, L; Rella, L; Ranieri, V; Cirili, A; Stabile Ianora, A A; Angelelli, G

2015-01-01

To assess the diagnostic accuracy of specimen ultrasound (US) for predicting resection margin status in women undergoing breast conserving therapy for US-detected cancer, having the histological findings as the reference standard. A total of 132 consecutive patients (age range, 34-87 years; mean, 51 years) underwent breast-conserving surgery for US-detected invasive breast cancer. All surgical specimens underwent US examination. The presence of lesion within the specimen and its distance from the specimen margins were assessed considering a threshold distance between the lesion and specimen margins of 10 mm. US findings were then compared with the pathological ones and specimen US. Sensitivity, specificity, diagnostic accuracy, positive (PPV) and negative predictive values (NPV) for predicting histological margin status were evaluated, having the histological findings as the reference standard. The histological examination detected invasive ductal carcinoma in 96/132 (73%) cases, invasive lobular carcinoma in 32/132 (24%), mucinous carcinoma in 4/132 (3%). The pathological margin analysis revealed 96/132 (73%) negative margins and 36 (27%) close/positive margins. US examination detected all 132 breast lesions within the surgical specimens. 110 (83%) negative margins and 22 (17%) positive margins were found on US. Sensitivity, specificity, diagnostic accuracy, PPV and NPV of 44%, 94%, 80%, 73% and 82%, respectively, were found for specimen US. Specimen US represents a time and cost saving imaging tool for evaluating the presence of US detected-breast lesion within surgical specimen and for predicting the histological margin status.

Patterns of failure for glioblastoma multiforme following limited-margin radiation and concurrent temozolomide

International Nuclear Information System (INIS)

Gebhardt, Brian J; Dobelbower, Michael C; Ennis, William H; Bag, Asim K; Markert, James M; Fiveash, John B

2014-01-01

To analyze patterns of failure in patients with glioblastoma multiforme (GBM) treated with limited-margin radiation therapy and concurrent temozolomide. We hypothesize that patients treated with margins in accordance with Adult Brain Tumor Consortium guidelines (ABTC) will demonstrate patterns of failure consistent with previous series of patients treated with 2–3 cm margins. A retrospective review was performed of patients treated at the University of Alabama at Birmingham for GBM between 2000 and 2011. Ninety-five patients with biopsy-proven disease and documented disease progression after treatment were analyzed. The initial planning target volume includes the T1-enhancing tumor and surrounding edema plus a 1 cm margin. The boost planning target volume includes the T1-enhancing tumor plus a 1 cm margin. The tumors were classified as in-field, marginal, or distant if greater than 80%, 20-80%, or less than 20% of the recurrent volume fell within the 95% isodose line, respectively. The median progression-free survival from the time of diagnosis to documented failure was 8 months (range 3–46). Of the 95 documented recurrences, 77 patients (81%) had an in-field component of treatment failure, 6 (6%) had a marginal component, and 27 (28%) had a distant component. Sixty-three patients (66%) demonstrated in-field only recurrence. The low rate of marginal recurrence suggests that wider margins would have little impact on the pattern of failure, validating the use of limited margins in accordance ABTC guidelines

Whipple Resection: Concordance Between Frozen Section And Permanent Section Diagnosis Of Surgical Margins.

Science.gov (United States)

Bilal, Muhammad; Tariq, Hina; Mamoon, Nadira

2018-01-01

Margin assessment is done in Whipple procedures which are usually performed to resect tumours of head of pancreas and ampullary/periampullary region. Aims and objective of the study are to determine the concordance between frozen sections (FS) and permanent sections (PS) of surgical margins in Whipple resections. It is a retrospective study, from January 2008 to January 2015 (07 years). It includes the specimen with malignancy in final report and for which FS of pancreatic and/or CBD margin(s) were requested. Data was retrieved from Laboratory information system (LIS) database. Of the 41 bile duct margins in cases of ampullary tumours, 03 were positive on FS as well as PS, 35 were negative on FS as well as on PS. Results showed 100% sensitivity, 92.1% specificity, 50% PPV and 100% NPV. Results of 36 pancreatic margins in cases of ampullary showed 100% sensitivity, 97.1% specificity, 50% PPV and 100% NPV. In pancreatic carcinoma cases, none of CBD margins were reported as positive on FS, 02 margins reported as negative were found positive on PS, while 17 were negative on FS as well as PS. Results showed 100% specificity and 89.5% NPV. Of the 27 pancreatic margins tested in pancreatic tumours 100% sensitivity, 94.1% specificity, 88.9% PPV and 100% NPV was found. Factors such as absent prior tissue diagnosis and/or inflammatory processes make margin diagnosis difficult. However, a high concordance was observed between our FS and PS diagnosis.

Atlantic continental margin of the United States

Science.gov (United States)

Grow, John A.; Sheridan, Robert E.; Palmer, A.R.

1982-01-01

The objective of this Decade of North American Geology (D-NAG) volume will be to focus on the Mesozoic and Cenozoic evolution of the U.S. Atlantic continental margin, including the onshore coastal plain, related onshore Triassic-Jurassic rift grabens, and the offshore basins and platforms. Following multiple compressional tectonic episodes between Africa and North America during the Paleozoic Era that formed the Appalachian Mountains, the Mesozoic and Cenozoic Eras were dominated by tensional tectonic processes that separated Africa and North America. Extensional rifting during Triassic and Early Jurassic times resulted in numerous tensional grabens both onshore and offshore, which filled with nonmarine continental red beds, lacustrine deposits, and volcanic flows and debris. The final stage of this breakup between Africa and North America occurred beneath the present outer continental shelf and continental slope during Early or Middle Jurassic time when sea-floor spreading began to form new oceanic crust and lithosophere between the two continents as they drifted apart. Postrift subsidence of the marginal basins continued in response to cooling of the lithosphere and sedimentary loading.Geophysical surveys and oil-exploration drilling along the U.S. Atlantic continental margin during the past 5 years are beginning to answer many questions concerning its deep structure and stratigraphy and how it evolved during the rifting and early sea-floor-spreading stages of the separation of this region from Africa. Earlier geophysical studies of the U.S. continental margin used marine refraction and submarine gravity measurements. Single-channel seismic-reflection, marine magnetic, aeromagnetic, and continuous gravity measurements became available during the 1960s.

SU-F-BRD-07: Empirical Derivation of Site-Specific Margin Formulas

International Nuclear Information System (INIS)

Conroy, L; Smith, W; Quirk, S

2014-01-01

Purpose: To empirically derive margin formulas from existing clinical radiotherapy plans accounting for respiratory motion and setup uncertainties. Methods: We simulated realistic treatment scenarios, including respiratory motion and setup errors. Individual probability density functions (PDF) from respiratory data were used to simulate respiratory motion. Random (σ) and systematic (Σ) setup errors were modeled as Gaussian distributions. One-dimensional dose profiles were extracted from existing radiotherapy plans and convolved with respiratory PDFs and random error distributions to produce blurred dose profiles. Each blurred dose profile was then shifted 1000 times by randomly sampling the simulated systematic error distribution. Margins were determined from the distance between the simulated treatment and the original 95% isodose level. An equation was fit for each (σ, Σ) combination to derive margin formulas for 90% of the population receiving 95% dose. This methodology can be applied to different tumor sites. Here, dose profiles were extracted from partial breast 3DCRT plans in the anterior-posterior (AP) and superior-inferior (SI) directions. Respiratory motion data was from healthy volunteers, and a clinically relevant range of random and systematic setup errors (standard deviations 1 – 4 mm) was determined from the literature. Results: The PBI margin formulas in the AP and SI directions for 95% dose coverage for 90% of the population were very similar: M= 0.68σ + 1.54Σ and M= 0.72σ + 1.50Σ, respectively. Systematic setup errors had the largest influence on required margin size, whereas realistic respiratory amplitude had minimal impact. The derived formulas resulted in a smaller systematic component than commonly-used theoretical margin recipes. Conclusion: We have demonstrated a method to derive empirical margin formulas from existing patient radiotherapy plans, incorporating realistic respiratory motion and appropriate ranges of random and

Deoxycholic Acid and the Marginal Mandibular Nerve: A Cadaver Study.

Science.gov (United States)

Blandford, Alexander D; Ansari, Waseem; Young, Jason M; Maley, Bruce; Plesec, Thomas P; Hwang, Catherine J; Perry, Julian D

2018-06-04

One of the rare but serious complications observed with deoxycholic acid administration is damage to the marginal mandibular nerve. In this study, we evaluated if deoxycholic acid directly induces histologic damage to fresh cadaveric marginal mandibular nerve. A segment of marginal mandibular nerve was harvested from 12 hemifaces of 6 fresh cadavers. The nerve specimen was exposed to either 0.9% sterile saline for 24 h, deoxycholic acid (10 mg/ml) for 20 min, or deoxycholic acid (10 mg/ml) for 24 h. The nerve specimens were then fixed in glutaraldehyde for a minimum of 24 h. Toluidine blue stained sections were evaluated for stain intensity using light microscopy and color deconvolution image analysis. Supraplatysmal fat was harvested as a positive control and exposed to the same treatments as the marginal mandibular nerve specimens, then evaluated using transmission electron microscopy. Toluidine blue staining was less in the marginal mandibular nerve exposed to deoxycholic acid when compared to saline. The specimen exposed to deoxycholic acid for 24 h showed less toluidine blue staining than that of the nerve exposed to deoxycholic acid for 20 min. Transmission electron microscopy of submental fat exposed to deoxycholic acid revealed disruption of adipocyte cell membrane integrity and loss of cellular organelles when compared to specimens only exposed to saline. Deoxycholic acid (10 mg/ml) damages the marginal mandibular nerve myelin sheath in fresh human cadaver specimens. Direct deoxycholic acid neurotoxicity may cause marginal mandibular nerve injury clinically. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The stability margin of elongated plasmas

International Nuclear Information System (INIS)

Portone, Alfredo

2005-01-01

Passive stabilization is a key feature in tokamak design since it indicates the efficiency of the metallic structures to 'oppose' plasma displacements. As far as plasma vertical displacement modes are concerned, usually their passive stabilization is characterized in terms of two main indices, namely the instability growth time and the stability margin. In this study-after recalling the governing equations-we extend the definition of the stability margin given in the literature (Lazarus E. et al 1990 Nucl. Fusion 30 111, Albanese R. et al 1990 IEEE Trans. Magn. 26, Kameari A. et al 1985 Nucl. Eng. Des./Fusion 365-73) for the rigid body displacement model to the non-rigid plasma model. Numerical examples are also given for the reduced task objectives/reduced cost ITER design

Seismic margin analysis technique for nuclear power plant structures

International Nuclear Information System (INIS)

Seo, Jeong Moon; Choi, In Kil

2001-04-01

In general, the Seismic Probabilistic Risk Assessment (SPRA) and the Seismic Margin Assessment(SAM) are used for the evaluation of realistic seismic capacity of nuclear power plant structures. Seismic PRA is a systematic process to evaluate the seismic safety of nuclear power plant. In our country, SPRA has been used to perform the probabilistic safety assessment for the earthquake event. SMA is a simple and cost effective manner to quantify the seismic margin of individual structural elements. This study was performed to improve the reliability of SMA results and to confirm the assessment procedure. To achieve this goal, review for the current status of the techniques and procedures was performed. Two methodologies, CDFM (Conservative Deterministic Failure Margin) sponsored by NRC and FA (Fragility Analysis) sponsored by EPRI, were developed for the seismic margin review of NPP structures. FA method was originally developed for Seismic PRA. CDFM approach is more amenable to use by experienced design engineers including utility staff design engineers. In this study, detailed review on the procedures of CDFM and FA methodology was performed

Determinants of the net interest margins in BH banks

Directory of Open Access Journals (Sweden)

Plakalović Novo

2015-01-01

Full Text Available In this paper, the subject of analysis is influence of certain macroeconomic and microeconomic variables on bank net interest margins in Bosnia and Herzegovina (BH for the period from 2008 to 2013 through a multiple linear regression models. The level and dynamics of NIM indicate the efficiency of financial intermediation. The observed period is characterized by the reduction in net interest margins of banks over the previous decade, which was characterized by high GDP growth, bank loans and high-interest rates and high profitability. Therefore, this study examines the factors that affect the level of net interest margins in the domestic banking industry. The main objective of this paper is to determine whether there is interdependence in the movement between the independent and dependent variables through a multiple linear regression. The net interest margin will be observed as a dependent variable, and liquidity risk, operating costs, credit risk, the index of market concentration, funding risk, the growth rate of gross domestic product and consumer price index will be used as independent variables.

A simple model for enamel fracture from margin cracks.

Science.gov (United States)

Chai, Herzl; Lee, James J-W; Kwon, Jae-Young; Lucas, Peter W; Lawn, Brian R

2009-06-01

We present results of in situ fracture tests on extracted human molar teeth showing failure by margin cracking. The teeth are mounted into an epoxy base and loaded with a rod indenter capped with a Teflon insert, as representative of food modulus. In situ observations of cracks extending longitudinally upward from the cervical margins are recorded in real time with a video camera. The cracks appear above some threshold and grow steadily within the enamel coat toward the occlusal surface in a configuration reminiscent of channel-like cracks in brittle films. Substantially higher loading is required to delaminate the enamel from the dentin, attesting to the resilience of the tooth structure. A simplistic fracture mechanics analysis is applied to determine the critical load relation for traversal of the margin crack along the full length of the side wall. The capacity of any given tooth to resist failure by margin cracking is predicted to increase with greater enamel thickness and cuspal radius. Implications in relation to dentistry and evolutionary biology are briefly considered.

“Marginal land” for energy crops: Exploring definitions and embedded assumptions

International Nuclear Information System (INIS)

Shortall, O.K.

2013-01-01

The idea of using less productive or “marginal land” for energy crops is promoted as a way to overcome the previous land use controversies faced by biofuels. It is argued that marginal land use would not compete with food production, is widely available and would incur fewer environmental impacts. This term is notoriously vague however, as are the details of how marginal land use for energy crops would work in practice. This paper explores definitions of the term “marginal land” in academic, consultancy, NGO, government and industry documents in the UK. It identifies three separate definitions of the term: land unsuitable for food production; ambiguous lower quality land; and economically marginal land. It probes these definitions further by exploring the technical, normative and political assumptions embedded within them. It finds that the first two definitions are normatively motivated: this land should be used to overcome controversies and the latter definition is predictive: this land is likely to be used. It is important that the different advantages, disadvantages and implications of the definitions are spelled out so definitions are not conflated to create unrealistic expectations about the role of marginal land in overcoming biofuels land use controversies. -- Highlights: •Qualitative methods were used to explore definitions of the term “marginal land”. •Three definitions were identified. •Two definitions focus on overcoming biomass land use controversies. •One definition predicts what land will be used for growing biomass. •Definitions contain problematic assumptions

Marginality and Variability in Esperanto.

Science.gov (United States)

Brent, Edmund

This paper discusses Esperanto as a planned language and refutes three myths connected to it, namely, that Esperanto is achronical, atopical, and apragmatic. The focus here is on a synchronic analysis. Synchronic variability is studied with reference to the structuralist determination of "marginality" and the dynamic linguistic…

Pushing the Margins of Responsibility

DEFF Research Database (Denmark)

Santoni de Sio, Filippo; Di Nucci, Ezio

2018-01-01

David Shoemaker has claimed that a binary approach to moral responsibility leaves out something important, namely instances of marginal agency, cases where agents seem to be eligible for some responsibility responses but not others. In this paper we endorse and extend Shoemaker’s approach by pres...

Medición de microdeformaciones en losas viales usando sensores de redes de Braggen fibras ópticas Microdeformation measurement of concrete roadway slabs using fiber Bragg gratings

OpenAIRE

Francisco Javier Vélez Hoyos; Claudia Milena Serpa Imbet; Nelson Darío Gómez Cardona

2010-01-01

En este trabajo se presenta un método no invasivo para la medición de microdeformaciones en estructuras de concreto usando sensores de redes de Bragg en fibras ópticas adheridos a su superficie. Se realizan mediciones en losas viales de concreto bajo una carga estática de 10 kN, encontrándose una relación aproximada de 2 : 1 entre la deformación registrada por los sensores y los valores arrojados por una simulación computacional con el método de elementos finitos. Se propone el uso de estos s...

Contrasting evidence of Holocene ice margin retreat, south-western Greenland

DEFF Research Database (Denmark)

Levy, L. B.; Larsen, N. K.; Davidson, T. A.

2017-01-01

Constraining the Greenland Ice Sheet's (GrIS) response to Holocene climate change provides calibrations for ice sheet models that hindcast past ice margin fluctuations. Ice sheet models predict enhanced ice retreat in south-western Greenland during the middle Holocene; however, few geological...... observations corroborating the extensive retreat are available. We present new data from lake sediment cores from the Isua region, south-western Greenland, which provide constraints on Holocene fluctuations of the GrIS margins. Our data indicate that the main GrIS margin was 30 km west of its present...

Analysis of safety margins for PuO2 containers

International Nuclear Information System (INIS)

Hubert, P.; Tomachevsky, E.

1987-11-01

In the regular manner the containers for PuO 2 transport are type B(U) and give satisfaction to the AIEA proofs. However the vigour of this conception's containers and the analysis of other radioactive containers permit to think that large safety margins exist. In this paper, the importance and the kind of these margins are studied [fr

Extensive management of field margins enhances their potential for off-site soil erosion mitigation.

Science.gov (United States)

Ali, Hamada E; Reineking, Björn

2016-03-15

Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mapping Mesophotic Reefs Along the Brazilian Continental Margin

Science.gov (United States)

Bastos, A.; Moura, R.; Amado Filho, G.; Ferreira, L.; Boni, G.; Vedoato, F.; D'Agostini, D.; Lavagnino, A. C.; Leite, M. D.; Quaresma, V.

2017-12-01

Submerged or drowned reefs constitute an important geological record of sea level variations, forming the substrate for the colonization of modern benthic mesophotic communities. Although mapping mesophotic reefs has increased in the last years, their spatial distribution is poorly known and the worldwide occurrence of this reef habitat maybe underestimated. The importance in recognizing the distribution of mesophotic reefs is that they can act as a refuge for corals during unsuitable environmental conditions and a repository for shallow water corals. Here we present the result of several acoustic surveys that mapped and discovered new mesophotic reefs along the Eastern and Equatorial Brazilian Continental Margin. Seabed mapping was carried out using multibeam and side scan sonars. Ground truthing was obtained using drop camera or scuba diving. Mesophotic reefs were mapped in water depths varying from 30 to 100m and under distinct oceanographic conditions, especially in terms of river load input and shelf width. Reefs showed distinct morphologies, from low relief banks and paleovalleys to shelf edge ridges. Extensive occurrence of low relief banks were mapped along the most important coralline complex province in the South Atlantic, the Abrolhos Shelf. These 30 to 40m deep banks, have no more than 3 meters in height and may represent fringing reefs formed during sea level stabilization. Paleovalleys mapped along the eastern margin showed the occurrence of coralgal ledges along the channel margins. Paleovalleys are usually deeper than 45m and are associated with outer shelf rhodolith beds. Shelf edge ridges (80 to 120m deep) were mapped along both margins and are related to red algal encrusting irregular surfaces that have more than 3m in height, forming a rigid substrate for coral growth. Along the Equatorial Margin, off the Amazon mouth, shelf edge patch reefs and rhodolith beds forming encrusting surfaces and shelf edge ridges were mapped in water depths greater

In vitro evaluation of marginal adaptation in five ceramic restoration fabricating techniques.

Science.gov (United States)

Ural, Cağri; Burgaz, Yavuz; Saraç, Duygu

2010-01-01

To compare in vitro the marginal adaptation of crowns manufactured using ceramic restoration fabricating techniques. Fifty standardized master steel dies simulating molars were produced and divided into five groups, each containing 10 specimens. Test specimens were fabricated with CAD/CAM, heat-press, glass-infiltration, and conventional lost-wax techniques according to manufacturer instructions. Marginal adaptation of the test specimens was measured vertically before and after cementation using SEM. Data were statistically analyzed by one-way ANOVA with Tukey HSD tests (a = .05). Marginal adaptation of ceramic crowns was affected by fabrication technique and cementation process (P cementation (P cementation. Marginal adaptation values obtained in the compared systems were within clinically acceptable limits. Cementation causes a significant increase in the vertical marginal discrepancies of the test specimens.

City and sea margins. Porto’s Marginal as scale and measure of new spaces

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Giuseppe Parità

2014-06-01

Full Text Available The city has always been confronting with its own end and the beginning of the water system. Among the different kind of margin areas, the ones that border the cities on their watersides are particularly interesting. These new liminal territories are rich in variety and differences and are set up of several elements made of different morphologies that should be carefully read and interpreted: the need of re-thinking the morphological elements that mark an urban edge leads to the identification of several shapes and forms of the water borderlands. Borders, limits, boundaries, edges, margin areas - usually considered as an obstacle to the construction of the city - turn themselves as new possible “design materials” for building that ambiguous distance between city and the sea. The article aims to focus on the case-study of Porto’s Marginal that well explain how many ways a city can live its water edges. On a large scale, it is configured as a strip of 15 kilometers of public space. Within this continuity, the different extent of the distance between city and water leads to reflect on the different types of relationships (and therefore projects between the end of one side and the beginning of another. For Porto, those are not only urban parts, but also different geographical parts (sea, rivers, topography that distance puts in relation through the design sometimes of the line, at time of the border or of a surface. So, the analysis of these heterogeneous but continuous projects aim to focus on the several techniques of urban composition to build contemporary public spaces. On one hand they give form to a continuous “public figure”, on the other hand each one of the project can be considered as part of a “atlas” of liminal places, giving form to public spaces. 

Ecological and evolutionary processes at expanding range margins

OpenAIRE

Thomas, C.D.; Bodsworth, E.J.; Wilson, R.J.; Simmons, A.D.; Davies, Z.G.; Musche, M.; Conradt, L.

2001-01-01

Many animals are regarded as relatively sedentary and specialized in marginal parts of their geographical distributions. They are expected to be slow at colonizing new habitats. Despite this, the cool margins of many species' distributions have expanded\\ud rapidly in association with recent climate warming3±10. We examined four insect species that have expanded their geographical\\ud ranges in Britain over the past 20 years. Here we report that two butterfly species have increased the variety ...

Contributions to knowledge of the continental margin of Uruguay. Uruguayan continental margin: morphology, geology and identification of the base of the slope

International Nuclear Information System (INIS)

Preciozzi, F.

2014-01-01

This work is about the morphology, geology and the identification of the base of the slope in the The Uruguayan continental margin which corresponds to the the type of divergent, volcanic and segmented margins. Morphologically is constituted by a clearly defined continental shelf, as well as a continental slope that presents configuration changes from north to south and passes directly to the abyssal plain

A comparison of pay-as-bid and marginal pricing in electricity markets

Science.gov (United States)

Ren, Yongjun

This thesis investigates the behaviour of electricity markets under marginal and pay-as-bid pricing. Marginal pricing is believed to yield the maximum social welfare and is currently implemented by most electricity markets. However, in view of recent electricity market failures, pay-as-bid has been extensively discussed as a possible alternative to marginal pricing. In this research, marginal and pay-as-bid pricing have been analyzed in electricity markets with both perfect and imperfect competition. The perfect competition case is studied under both exact and uncertain system marginal cost prediction. The comparison of the two pricing methods is conducted through two steps: (i) identify the best offer strategy of the generating companies (gencos); (ii) analyze the market performance under these optimum genco strategies. The analysis results together with numerical simulations show that pay-as-bid and marginal pricing are equivalent in a perfect market with exact system marginal cost prediction. In perfect markets with uncertain demand prediction, the two pricing methods are also equivalent but in an expected value sense. If we compare from the perspective of second order statistics, all market performance measures exhibit much lower values under pay-as-bid than under marginal pricing. The risk of deviating from the mean is therefore much higher under marginal pricing than under pay-as-bid. In an imperfect competition market with exact demand prediction, the research shows that pay-as-bid pricing yields lower consumer payments and lower genco profits. This research provides quantitative evidence that challenges some common claims about pay-as-bid pricing. One is that under pay-as-bid, participants would soon learn how to offer so as to obtain the same or higher profits than what they would have obtained under marginal pricing. This research however shows that, under pay-as-bid, participants can at best earn the same profit or expected profit as under marginal

Maximum Margin Clustering of Hyperspectral Data

Science.gov (United States)

Niazmardi, S.; Safari, A.; Homayouni, S.

2013-09-01

In recent decades, large margin methods such as Support Vector Machines (SVMs) are supposed to be the state-of-the-art of supervised learning methods for classification of hyperspectral data. However, the results of these algorithms mainly depend on the quality and quantity of available training data. To tackle down the problems associated with the training data, the researcher put effort into extending the capability of large margin algorithms for unsupervised learning. One of the recent proposed algorithms is Maximum Margin Clustering (MMC). The MMC is an unsupervised SVMs algorithm that simultaneously estimates both the labels and the hyperplane parameters. Nevertheless, the optimization of the MMC algorithm is a non-convex problem. Most of the existing MMC methods rely on the reformulating and the relaxing of the non-convex optimization problem as semi-definite programs (SDP), which are computationally very expensive and only can handle small data sets. Moreover, most of these algorithms are two-class classification, which cannot be used for classification of remotely sensed data. In this paper, a new MMC algorithm is used that solve the original non-convex problem using Alternative Optimization method. This algorithm is also extended for multi-class classification and its performance is evaluated. The results of the proposed algorithm show that the algorithm has acceptable results for hyperspectral data clustering.

Profit margins in Japanese retailing

NARCIS (Netherlands)

J.C.A. Potjes; A.R. Thurik (Roy)

1993-01-01

textabstractUsing a rich data source, we explain differences and developments in profit margins of medium-sized stores in Japan. We conclude that the protected environment enables the retailer to pass on all operating costs to the customers and to obtain a relatively high basic income. High service

Influence of radiation dose on positive surgical margins in women undergoing breast conservation therapy

International Nuclear Information System (INIS)

DiBiase, Steven J.; Komarnicky, Lydia T.; Heron, Dwight E.; Schwartz, Gordon F.; Mansfield, Carl M.

2002-01-01

Purpose: Positive surgical margins adversely influence local tumor control in breast conservation therapy (BCT). However, reports have conflicted regarding whether an increased radiation dose can overcome this poor prognostic factor. In this study, we evaluated the influence of an increased radiation dose on tumor control in women with positive surgical margins undergoing BCT. Methods and Materials: Between 1978 and 1994, 733 women with pathologic Stage I-II breast cancer and known surgical margin status were treated at Thomas Jefferson University Hospital with BCT. Of these 733 patients, 641 women had a minimal tumor bed dose of 60 Gy and had documentation of their margin status; 509 had negative surgical margins, and 132 had positive surgical margins before definitive radiotherapy. Complete gross excision of the tumor and axillary lymph node sampling was obtained in all patients. The median radiation dose to the primary site was 65.0 Gy (range 60-76). Of the women with positive margins (n=132), the influence of higher doses of radiotherapy was evaluated. The median follow-up time was 52 months. Results: The local tumor control rate for patients with negative margins at 5 and 10 years was 94% and 88%, respectively, compared with 85% and 67%, respectively, for those women with positive margins (p=0.001). The disease-free survival rate for the negative margin group at 5 and 10 years was 91% and 82%, respectively, compared with 76% and 71%, respectively, for the positive margin group (p = 0.001). The overall survival rate of women with negative margins at 5 and 10 years was 95% and 90%, respectively. By comparison, for women with positive surgical margins, the overall survival rate at 5 and 10 years was 86% and 79%, respectively (p=0.008). A comparison of the positive and negative margin groups revealed that an increased radiation dose (whether entered as a dichotomous or a continuous variable) >65.0 Gy did not improve local tumor control (p=0.776). On Cox

Terraced margins of inflated lava flows on Earth and Mars

Science.gov (United States)

Zimbelman, J. R.; Garry, W. B.; Bleacher, J. E.; Crumpler, L. S.

2011-12-01

When fluid basaltic lava flows are emplaced over a shallow regional slope (typically much less than one degree), the lava flows often display impressive characteristics of inflation. Here we describe a distinctive marginal characteristic that is often developed along the margins of endogenously inflated basaltic lava flows; discreet topographic levels of the emplaced lava that are here termed 'terraced margins'. Terraced margins were first noted at the distal end of the Carrizozo lava flow in central New Mexico, where they are particularly well expressed, but terraces have also been observed along some margins of the McCartys lava flow (NM), the distal end of the 1859 Mauna Loa lava flow (HI), and lava flows at Craters of the Moon (ID). Differential Global Positioning System surveys across several terraced margins reveal consistent topographic characteristics: the upper surface of each terrace level is at roughly one half the height of the sheet lobe from which it emerges; when a terrace becomes the source of an additional outbreak, the upper surface of the second terrace is at roughly one half the height of the source terrace; often a subtle topographic depression is present along the contact between a terrace and its source sheet lobe, suggesting that the terrace outflow starts at a level roughly one-third the height of the source lobe; the upper surfaces of both the source sheet lobe and associated terraces are level to within tens of centimeters across length scales of many tens to hundreds of meters, indicative of inflation of all components. The field observations will be used as the constraints for modeling of the inflation and terracing mechanisms, an effort that has only recently started. The multiple imaging data sets now available for Mars have revealed the presence of terraced margins on some lava flows on Mars. Although detailed topographic data are not currently available for the Martian examples identified so far, the presence of terraced margins for

Nonlinear dynamics near the stability margin in rotating pipe flow

Science.gov (United States)

Yang, Z.; Leibovich, S.

1991-01-01

The nonlinear evolution of marginally unstable wave packets in rotating pipe flow is studied. These flows depend on two control parameters, which may be taken to be the axial Reynolds number R and a Rossby number, q. Marginal stability is realized on a curve in the (R, q)-plane, and the entire marginal stability boundary is explored. As the flow passes through any point on the marginal stability curve, it undergoes a supercritical Hopf bifurcation and the steady base flow is replaced by a traveling wave. The envelope of the wave system is governed by a complex Ginzburg-Landau equation. The Ginzburg-Landau equation admits Stokes waves, which correspond to standing modulations of the linear traveling wavetrain, as well as traveling wave modulations of the linear wavetrain. Bands of wavenumbers are identified in which the nonlinear modulated waves are subject to a sideband instability.

Centrifugal Compressor Surge Margin Improved With Diffuser Hub Surface Air Injection

Science.gov (United States)

Skoch, Gary J.

2002-01-01

Aerodynamic stability is an important parameter in the design of compressors for aircraft gas turbine engines. Compression system instabilities can cause compressor surge, which may lead to the loss of an aircraft. As a result, engine designers include a margin of safety between the operating line of the engine and the stability limit line of the compressor. The margin of safety is typically referred to as "surge margin." Achieving the highest possible level of surge margin while meeting design point performance objectives is the goal of the compressor designer. However, performance goals often must be compromised in order to achieve adequate levels of surge margin. Techniques to improve surge margin will permit more aggressive compressor designs. Centrifugal compressor surge margin improvement was demonstrated at the NASA Glenn Research Center by injecting air into the vaned diffuser of a 4:1-pressure-ratio centrifugal compressor. Tests were performed using injector nozzles located on the diffuser hub surface of a vane-island diffuser in the vaneless region between the impeller trailing edge and the diffuser-vane leading edge. The nozzle flow path and discharge shape were designed to produce an air stream that remained tangent to the hub surface as it traveled into the diffuser passage. Injector nozzles were located near the leading edge of 23 of the 24 diffuser vanes. One passage did not contain an injector so that instrumentation located in that passage would be preserved. Several orientations of the injected stream relative to the diffuser vane leading edge were tested over a range of injected flow rates. Only steady flow (nonpulsed) air injection was tested. At 100 percent of the design speed, a 15-percent improvement in the baseline surge margin was achieved with a nozzle orientation that produced a jet that was bisected by the diffuser vane leading edge. Other orientations also improved the baseline surge margin. Tests were conducted at speeds below the

Impact of organ shape variations on margin concepts for cervix cancer ART.

Science.gov (United States)

Seppenwoolde, Yvette; Stock, Markus; Buschmann, Martin; Georg, Dietmar; Bauer-Novotny, Kwei-Yuang; Pötter, Richard; Georg, Petra

2016-09-01

Target and organ movement motivate adaptive radiotherapy for cervix cancer patients. We investigated the dosimetric impact of margin concepts with different levels of complexity on both organ at risk (OAR) sparing and PTV coverage. Weekly CT and daily CBCT scans were delineated for 10 patients. The dosimetric impact of organ shape variations were evaluated for four (isotropic) margin concepts: two static PTVs (PTV 6mm and PTV 15mm ), a PTV based on ITV of the planning CT and CBCTs of the first treatment week (PTV ART ITV ) and an adaptive PTV based on a library approach (PTV ART Library ). Using static concepts, OAR doses increased with large margins, while smaller margins compromised target coverage. ART PTVs resulted in comparable target coverage and better sparing of bladder (V40Gy: 15% and 7% less), rectum (V40Gy: 18 and 6cc less) and bowel (V40Gy: 106 and 15cc less) compared to PTV 15mm . Target coverage evaluation showed that for elective fields a static 5mm margin sufficed. PTV ART Library achieved the best dosimetric results. However when weighing clinical benefit against workload, ITV margins based on repetitive movement evaluation during the first week also provide improvements over static margin concepts. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Middlemen Margins and Globalization

OpenAIRE

Pranab Bardhan; Dilip Mookherjee; Masatoshi Tsumagari

2013-01-01

We develop a theory of trading middlemen or entrepreneurs who perform financing, quality supervision and marketing roles for goods produced by suppliers or workers. Brand-name reputations are necessary to overcome product quality moral hazard problems; middlemen margins represent reputational incentive rents. We develop a two sector North-South model of competitive equilibrium, with endogenous sorting of agents with heterogenous entrepreneurial abilities into sectors and occupations. The Sout...

Monitoreo de cambios en la densidad de cobertura forestal en bosque templado usando fotografías aéreas digitales de alta resolución

Directory of Open Access Journals (Sweden)

José López García

2016-08-01

Full Text Available Se utilizaron series multitemporales de fotografías aéreas digitales de alta resolución de pequeño formato para evaluar los cambios en la densidad de cobertura forestal en un bosque templado. Una combinación de técnicas convencionales y adaptadas de fotogrametría y fotointerpretación fueron utilizadas para establecer un método específico de evaluación.  Este método ha sido probado en un periodo de doce años (1999-2011 en la zona núcleo de la Reserva de la Biósfera Mariposa Monarca, localizada en los estados de México y Michoacán, en México, usando mosaicos ortorectificados como mapas base para evaluar cambios bienales. Las imágenes fueron fotointerpretadas de manera tradicional marcando los cambios sobre acetatos, colocados sobre las imágenes impresas, creando así nuevos polígonos. Estos fueron transferidos directamente de los acetatos al ortomosaico a través de la pantalla de la computadora, usando al menos tres puntos de control, cumpliendo así con el principio de triangulación radial. El bosque fue separado en las siguientes clases de cobertura forestal: cerrada, semi-cerrada, semi-abierta, abierta y deforestada. La evaluación en la exactitud en la clasificación de densidad de cobertura fue estimada a través de muestreos en campo, empleando matrices de confusión, siendo del 95%. A partir de 2003, este método ha sido utilizado para determinar el pago por servicios ambientales. Dicho pago, junto con una gran interacción con las comunidades, se ha traducido en una reducción en la degradación forestal y la deforestación en la zona núcleo de la Reserva.

Export Margins, Price and Quantity of Belarus’s Export Growth

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Otamurodov Shavkat

2017-03-01

Full Text Available This paper examines the sources of Belarus’s export growth and decomposes export growth into extensive and intensive margins. This study also aims to determine export margins for intermediate and final goods and to determine the price and quantity components of the intensive export margin. In order to achieve the desired objectives, we use two methods for decomposing export growth, the count method and the export shares method. We analyse Belarus's export growth using export data at the HS-6 digit level for the 2004-2014 period. Our results show that Belarus's exports grew mainly due to growth in the price margin during the studied period 2004-2014. However, the extensive margin was important in export growth to some extent. Comparing the growth rate across final and intermediate goods reveals that although the share of final products in Belarus’s exports is not very big (18.9% in 2014, the average annual growth in exports of final products is higher than that of intermediate goods. Our investigation also shows that Belarus produces a wide range of commodities, but the share of the most of these commodities is not large; its exports depend on a restricted range of commodities. Moreover, most of the commodities are exported to Russia and Ukraine. Our results give us reason to assume that finding new markets for their new products is one of the main challenges for developing countries wishing to increase their exports by an extensive margin. This has important implications for how policy makers promote the trade and diversification of exports.

Effect of two prophylaxis methods on marginal gap of Cl Vresin-modified glass-ionomer restorations.

Science.gov (United States)

Kimyai, Soodabeh; Pournaghi-Azar, Fatemeh; Daneshpooy, Mehdi; Abed Kahnamoii, Mehdi; Davoodi, Farnaz

2016-01-01

Background. This study evaluated the effect of two prophylaxis techniques on the marginal gap of CI V resin-modified glass-ionomer restorations. Methods. Standard Cl V cavities were prepared on the buccal surfaces of 48 sound bovine mandibular incisors in this in vitro study. After restoration of the cavities with GC Fuji II LC resin-modified glass-ionomer, the samples were randomly assigned to 3 groups of 16. In group 1, the prophylactic procedures were carried out with rubber cup and pumice powder and in group 2 with air-powder polishing device (APD). In group 3 (control), the samples did not undergo any prophylactic procedures. Then the marginal gaps were measured. Two-way ANOVA was used to compare marginal gaps at the occlusal and gingival margins between the groups. Post hoc Tukey test was used for two-by-two comparisons. Statistical significance was set at P marginal gaps in terms of prophylactic techniques (P marginal gaps in the APD group compared to the pumice and rubber cup group, which in turn exhibited significantly larger marginal gaps compared to the control group (P marginal gaps were significant in terms of the margin type (P margins compared to the occlusal margins (P marginal gaps of Cl V resin-modified glass-ionomer restorations.

APROXIMACIÓN AL ANÁLISIS DE LA VALORACIÓN DE LA PRUEBA USANDO MODIFIED WIGMOREAN ANALYSIS (MWA

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Carlos del Valle Rojas

2009-01-01

Full Text Available El presente trabajo muestra cómo el análisis de la valoración de la prueba, usando herramientas de diagramación argumental, puede ayudar a los operadores jurídicos a evaluar la calidad de la argumentación del razonamiento jurídico. Se aplica el Modified Wigmorean Analysis (MWA a un caso penal hipotético y a un caso real, ensayando el proceso de análisis y diagramación y probando su utilidad. La conclusión reseña las ventajas y debilidades del análisis y sugiere ajustes al proceso de diagramación.The present work shows how the analysis of the valuation of the proof, using tools of plot diagramming, can help the juridical operators to evaluate the quality of the argumentation of the juridical reasoning. There is applied the Modified Wigmorean Analysis (MWA to a penal hypothetical case and to a real case, testing the process of analysis and diagramming and proving his utility. The conclusion outlines the advantages and weaknesses of the analysis and suggests adjustments to the process of diagramming.

Pirólise catalítica do PEBD usando como catalisador a vermiculita modificada

Directory of Open Access Journals (Sweden)

Franciel Aureliano Bezerra

2016-01-01

Full Text Available Resumo O polietileno de baixa densidade (PEBD é um dos polímeros mais usados atualmente, e a grande quantidade desse polímero produzida resulta em toneladas de resíduos, que necessitam ser tratados. Neste trabalho foi realizada a pirólise termocatalítica do PEBD usando como catalisador a argila vermiculita modificada, como alternativa para o tratamento dos resíduos. A argila foi tratada com solução de ácido nítrico a diferentes concentrações e calcinada a 400 °C. Os materiais foram caracterizados por técnicas de difratometria de raios X, termogravimetria, adsorção de nitrogênio e espectroscopia de energia dispersiva. A pirólise térmica e termocatalítica foi realizada em um micro reator acoplado com GC/MS, a 500 °C. O intuito da pirólise de resíduos poliméricos é a obtenção de hidrocarbonetos leves (C<16, que possam ser empregados na indústria química e petroquímica, através de quebras na cadeia polimérica. Os resultados foram satisfatórios, com aumento no rendimento para hidrocarbonetos leves ao empregar os catalisadores chegando a 71,4% de produtos com C<16, enquanto a pirólise térmica resultou apenas de 25,8%.

Negotiating autonomy at the margins of the state

DEFF Research Database (Denmark)

Eilenberg, Michael

2009-01-01

Recent processes of decentralization have dramatically changed local political configurations and access to resources throughout Indonesia. In particular, the resource-rich regions at the margins of the state have, in the name of regional autonomy, experienced new spaces for manoeuvre in their cl......Recent processes of decentralization have dramatically changed local political configurations and access to resources throughout Indonesia. In particular, the resource-rich regions at the margins of the state have, in the name of regional autonomy, experienced new spaces for manoeuvre...

Air-Sea Interactions in the Marginal Ice Zone

Science.gov (United States)

2016-03-31

elementascience.org Air-sea interactions in the marginal ice zoneAir-Sea interactions in the Marginal Ice Zone Seth Zippel1* • Jim Thomson1 1Applied...Bidlot, 2013; Collins -III et al., 2015). Spectral wave directions and spread are given in Figure 5, where the difference in wave and wind direction...359219a0. Chalikov DV, Belevich MY. 1993. One-dimensional theory of the wave boundary layer. Bound-Lay Meteor 63: 65–96. Collins -III CO, Rogers WE

Univariate decision tree induction using maximum margin classification

OpenAIRE

Yıldız, Olcay Taner

2012-01-01

In many pattern recognition applications, first decision trees are used due to their simplicity and easily interpretable nature. In this paper, we propose a new decision tree learning algorithm called univariate margin tree where, for each continuous attribute, the best split is found using convex optimization. Our simulation results on 47 data sets show that the novel margin tree classifier performs at least as good as C4.5 and linear discriminant tree (LDT) with a similar time complexity. F...

Excision margin status: does it impact on local control of breast cancer?

International Nuclear Information System (INIS)

Lamoury, G.; Morgan, G.; Ward, R.

2003-01-01

Whilst many patients treated with breast conservation undergo re-excision(s) to obtain clear margins, the relationship between clear margins and local recurrence remains unclear. We aimed to determine the impact of final pathological margin status on local recurrence and other breast cancer outcomes. Our study cohort consisted of 755 consecutive patients treated with breast conservation between January 1984 and December 1995. Pathology reports were available for review in 681subjects (90%). Patients were stratified into 8 groups based on final pathological margin status: 1) negative (>3mm, n = 307), close [further divided into two groups 2) >0 1< 2mm, (n = 67)], 4) positive (n= 79), 5) indeterminate (n= 144), 6) low grade DCIS at the margin (n= 3), 7) high grade DCIS at the margin (n= 23) and 8) LCIS at the margin (n= 4). There were no differences between the groups based on histology, T size, grade, LN positivity or total radiation dose. At a median follow-up of 71 months, the breast relapse free survival (BRFS) was 97%, the distant metastasis free survival (DMFS) 78% and the overall survival (OS) 86%, for the entire cohort. There were no statistically significant differences between the negative, close, and positive groups in terms of BRFS: 96% vs. 94% vs. 93% (p=0.59), MFS: 98% vs. 97% vs. 98% (p=0.87) or OS: 84%vs. 85% vs. 86% (p=0.78). Although not statistically significant, the presence of EIC, in the context of close or positive margins, impacted adversely upon local and overall disease free survival. Patients undergoing breast conservation carry a lifelong risk of local recurrence. It is still not clear whether obtaining a radical margin decreases this risk. Tissue microarray analysis will be performed to further elucidate the causes of ipsilateral recurrence at a molecular and genetic level

Geomorphology and Neogene tectonic evolution of the Palomares continental margin (Western Mediterranean)

Science.gov (United States)

Gómez de la Peña, Laura; Gràcia, Eulàlia; Muñoz, Araceli; Acosta, Juan; Gómez-Ballesteros, María; R. Ranero, César; Uchupi, Elazar

2016-10-01

The Palomares continental margin is located in the southeastern part of Spain. The margin main structure was formed during Miocene times, and it is currently part of the wide deformation zone characterizing the region between the Iberian and African plates, where no well-defined plate boundary occurs. The convergence between these two plates is here accommodated by several structures, including the left lateral strike-slip Palomares Fault. The region is characterized by sparse, low to moderate magnitude (Mw shallow instrumental earthquakes, although large historical events have also occurred. To understand the recent tectonic history of the margin we analyze new high-resolution multibeam bathymetry data and re-processed three multichannel seismic reflection profiles crossing the main structures. The analysis of seafloor morphology and associated subsurface structure provides new insights of the active tectonic features of the area. In contrast to other segments of the southeastern Iberian margin, the Palomares margin contains numerous large and comparatively closely spaced canyons with heads that reach near the coast. The margin relief is also characterized by the presence of three prominent igneous submarine ridges that include the Aguilas, Abubacer and Maimonides highs. Erosive processes evidenced by a number of scars, slope failures, gullies and canyon incisions shape the present-day relief of the Palomares margin. Seismic images reveal the deep structure distinguishing between Miocene structures related to the formation of the margin and currently active features, some of which may reactivate inherited structures. The structure of the margin started with an extensional phase accompanied by volcanic accretion during the Serravallian, followed by a compressional pulse that started during the Latemost Tortonian. Nowadays, tectonic activity offshore is subdued and limited to few, minor faults, in comparison with the activity recorded onshore. The deep Algero

Overview of seismic margin insights gained from seismic PRA results

International Nuclear Information System (INIS)

Kennedy, R.P.; Sues, R.H.; Campbell, R.D.

1986-01-01

This paper presents the findings of a study conducted under NRC and EPRI sponsorship in which published seismic PRAs were reviewed in order to gain insight to the seismic margins inherent in existing nuclear plants. The approach taken was to examine the fragilities of those components which have been found to be dominant contributors to seismic risk at plants in low-to-moderate seismic regions (SSE levels between 0.12g and 0.25g). It is concluded that there is significant margin inherent in the capacity of most critical components above the plant design basis. For ground motions less than about 0.3g, the predominant sources of seismic risk are loss of offsite power coupled with random failure of the emergency diesels, non-recoverable circuit breaker trip due to relay chatter, unanchored equipment, unreinforced non-load bearing block walls, vertical water storage tanks, systems interactions and possibly soil liquefaction. Recommendations as to which components should be reviewed in seismic margin studies for margin earthquakes less than 0.3g, between 0.3g and 0.5g, and greater than 0.5g, developed by the NRC expert panel on the quantification of seismic margins (based on the review of past PRA data, earthquake experience data, and their own personal experience) are presented

Ocean Margins Programs, Phase I research summaries

Energy Technology Data Exchange (ETDEWEB)

Verity, P. [ed.

1994-08-01

During FY 1992, the DOE restructured its regional coastal-ocean programs into a new Ocean Margins Program (OMP), to: Quantify the ecological and biogeochemical processes and mechanisms that affect the cycling, flux, and storage of carbon and other biogenic elements at the land/ocean interface; Define ocean-margin sources and sinks in global biogeochemical cycles, and; Determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or export to the interior ocean. Currently, the DOE Ocean Margins Program supports more than 70 principal and co-principal investigators, spanning more than 30 academic institutions. Research funded by the OMP amounted to about $6.9M in FY 1994. This document is a collection of abstracts summarizing the component projects of Phase I of the OMP. This phase included both research and technology development, and comprised projects of both two and three years duration. The attached abstracts describe the goals, methods, measurement scales, strengths and limitations, and status of each project, and level of support. Keywords are provided to index the various projects. The names, addresses, affiliations, and major areas of expertise of the investigators are provided in appendices.

Policy Implementation, Role Conflict and Marginalization

African Journals Online (AJOL)

Prince Acheampong

governance, their role has been politically, administratively, and financially ... of marginalization of the Traditional Systems in terms of legal, financial and ..... the President as the Chief Executive Officer of the district is another controlling factor.

Asymmetric rifting, breakup and magmatism across conjugate margin pairs: insights from Newfoundland to Ireland

Science.gov (United States)

Peace, Alexander L.; Welford, J. Kim; Foulger, Gillian R.; McCaffrey, Ken J. W.

2017-04-01

Continental extension, subsequent rifting and eventual breakup result in the development of passive margins with transitional crust between extended continental crust and newly created oceanic crust. Globally, passive margins are typically classified as either magma-rich or magma-poor. Despite this simple classification, magma-poor margins like the West Orphan Basin, offshore Newfoundland, do exhibit some evidence of localized magmatism, as magmatism to some extent invariably accompanies all continental breakup. For example, on the Newfoundland margin, a small volcanic province has been interpreted near the termination of the Charlie Gibbs Fracture Zone, whereas on the conjugate Irish margin within the Rockall Basin, magmatism appears to be more widespread and has been documented both in the north and in the south. The broader region over which volcanism has been identified on the Irish margin is suggestive of magmatic asymmetry across this conjugate margin pair and this may have direct implications for the mechanisms governing the nature of rifting and breakup. Possible causes of the magmatic asymmetry include asymmetric rifting (simple shear), post-breakup thermal anomalies in the mantle, or pre-existing compositional zones in the crust that predispose one of the margins to more melting than its conjugate. A greater understanding of the mechanisms leading to conjugate margin asymmetry will enhance our fundamental understanding of rifting processes and will also reduce hydrocarbon exploration risk by better characterizing the structural and thermal evolution of hydrocarbon bearing basins on magma-poor margins where evidence of localized magmatism exists. Here, the latest results of a conjugate margin study of the Newfoundland-Ireland pair utilizing seismic interpretation integrated with other geological and geophysical datasets are presented. Our analysis has begun to reveal the nature and timing of rift-related magmatism and the degree to which magmatic asymmetry

Marginal cost and congestion in the Italian electricity market: An indirect estimation approach

International Nuclear Information System (INIS)

Bigerna, Simona; Andrea Bollino, Carlo; Polinori, Paolo

2015-01-01

In this paper we construct an indirect measure of the supply marginal cost function for the main generators from the observed bid data in the Italian electricity market in the period 2004–2007. We compute the residual demand function for each generator, taking explicitly into account the issue of transmission line congestion. This procedure allows recovering correct zonal Lerner index and the implied measure of the marginal cost function. We find evidence of a stable U-shaped marginal cost function for three main Italian generators, but a flat function for ENEL, the former national monopolist. The policy relevance of our approach lies in the possibility to offer some empirical knowledge of the marginal cost function of each generator to the regulator to design appropriate policy measures geared to the promotion of competitive market conditions. We propose a new market surveillance mechanism, which is based on the principle of sanctioning excessive deviations from the estimated measure of the marginal cost function presented in this work. -- Highlights: •We construct an indirect measure of the supply marginal cost function. •We compute the residual demand function taking into account transmission line congestion. •We find a general evidence of a stable U-shaped marginal cost function for Italian generators. •We find flat marginal cost function for the former national monopolist. •We use excessive deviations from estimated marginal cost function as a new market surveillance mechanism

Real analytic solutions for marginal deformations in open superstring field theory

International Nuclear Information System (INIS)

Okawa, Yuji

2007-01-01

We construct analytic solutions for marginal deformations satisfying the reality condition in open superstring field theory formulated by Berkovits when operator products made of the marginal operator and the associated superconformal primary field are regular. Our strategy is based on the recent observation by Erler that the problem of finding solutions for marginal deformations in open superstring field theory can be reduced to a problem in the bosonic theory of finding a finite gauge parameter for a certain pure-gauge configuration labeled by the parameter of the marginal deformation. We find a gauge transformation generated by a real gauge parameter which infinitesimally changes the deformation parameter and construct a finite gauge parameter by its path-ordered exponential. The resulting solution satisfies the reality condition by construction

Real analytic solutions for marginal deformations in open superstring field theory

International Nuclear Information System (INIS)

Okawa, Y.

2007-04-01

We construct analytic solutions for marginal deformations satisfying the reality condition in open superstring field theory formulated by Berkovits when operator products made of the marginal operator and the associated superconformal primary field are regular. Our strategy is based on the recent observation by Erler that the problem of finding solutions for marginal deformations in open superstring field theory can be reduced to a problem in the bosonic theory of finding a finite gauge parameter for a certain pure-gauge configuration labeled by the parameter of the marginal deformation. We find a gauge transformation generated by a real gauge parameter which infinitesimally changes the deformation parameter and construct a finite gauge parameter by its path-ordered exponential. The resulting solution satisfies the reality condition by construction. (orig.)

Evaluation of thermal margin for HANARO core

Energy Technology Data Exchange (ETDEWEB)

Park, Cheol; Chae, Hee Taek; Kim Heon Il; Lim, I. C.; Lee, C. S.; Kim, H

1999-08-01

During the commissioning and the start-up of the HANARO, various design parameters were confirmed and measured. For safer operation of HANARO and resolution of the CHF penalty issue which is one of unresolved licensing problems, thermal margins for normal and transient conditions were re-evaluated reflecting the commissioning and the start-up test results and the design modifications during operation. The re-evaluation shows that the HANARO meets the design criteria for ONB margin and fuel centerline temperature under normal condition. For upset condition, it also satisfies the safety limits for CHFR and fuel centerline temperature. (Author). 11 refs., 13 tabs., 4 figs.

MODELAMIENTO DE LA CINÉTICA DE BIOADSORCIÓN DE Cr (III USANDO CÁSCARA DE NARANJA

Directory of Open Access Journals (Sweden)

MARTHA LUCIA PINZÓN-BEDOYA

2009-01-01

Full Text Available En este trabajo se utilizó como material bioadsorbente cáscara naranja con el fin de remover iones cromo presentes en soluciones hipotéticas diluidas, utilizadas como modelo de aguas contaminadas con bajas concentraciones de este metal. Las condiciones de operación utilizadas fueron: relación sólido/líquido 4 g/l, tamaño de partícula ??0,425 mm, concentración inicial de disolución de Cr(III 100 mg/l, tiempo de contacto 60 h y pH constante (4 y 5. Los modelos cinéticos escogidos para identificar el mecanismo de reacción del proceso de bioadsorción usando cáscara de naranja fueron: primer orden reversible, pseudo- segundoorden, Elovich y difusión intraparticular. Los resultados indican que la ecuación de Elovich proporciona mayor exactitud en el ajuste de los datos experimentales del equilibrio a este modelo cinético. La bondad del ajuste de los datos se realizó por regresión no-lineal utilizando como criterio la minimización de la función objeto suma de los cuadrados del error, SCE, haciendo uso de la herramienta matemática MATLAB.

The role of the extensive margin in export of Turkey: A comparative analysis

Directory of Open Access Journals (Sweden)

Altan Aldan

2016-06-01

Full Text Available We examine the role of extensive margin, in other words, new export products and destinations, on Turkish export performance between 1995 and 2013, in comparison with some other countries. We use two complementary methods together with several extensions taking into account critiques in the literature. Our results suggest that, Turkey was quite successful in extending its extensive margin compared to other developing countries. The growth of extensive margin mostly comes from entering into new markets. Nevertheless, the level of the extensive margin is still low as of 2013 compared to the other countries. Turkey still has important opportunities to increase its exports via extensive margin especially in products.

Assessment of Biomass Resources from Marginal Lands in APEC Economies

Energy Technology Data Exchange (ETDEWEB)

Milbrandt, A.; Overend, R. P.

2009-08-01

The goal of this study is to examine the marginal lands in Asia-Pacific Economic Cooperation (APEC) economies and evaluate their biomass productivity potential. Twelve categories of marginal lands are identified using the Global Agro-Ecological Zones system of the United Nations Food and Agriculture Organization.

Street Sex Work: Re/Constructing Discourse from Margin to Center

Science.gov (United States)

McCracken, Jill Linnette

2009-01-01

Newspaper media create interpretations of marginalized groups that require rhetorical analysis so that we can better understand these representations. This article focuses on how newspaper articles create interpretations of sex work that affect both the marginalized and mainstream communities. My ethnographic case study argues that the material…

Un estudio sobre el desarrollo del pensamiento aleatorio usando recursos educativos abiertos

Directory of Open Access Journals (Sweden)

Yenny Patricia Pinzón Triana

2015-04-01

Full Text Available Este estudio presenta los resultados de un proyecto de investigación sobre la implementación de la enseñanza probabilística con recursos educativos abiertos (REA, diseñados en la plataforma Edmodo, y que está dirigido a estudiantes de tercer grado de educación básica secundaria de Bogotá, Colombia, y Tuxtepec, México. El fin era evidenciar sus preconceptos, nociones y evaluar el resultado de la instrucción en términos de su pensamiento probabilístico y dar respuesta a la interrogante ¿cuál es el efecto de la instrucción en probabilidad usando Edmodo en estudiantes de tercer grado de educación básica secundaria respecto a la valoración de fenómenos aleatorios de la vida cotidiana, sus conjeturas y la toma de decisiones? Se empleó un enfoque cualitativo a partir del método de estudio de casos, desde el análisis particular a lo general (Stake, 2005. Para la implementación, se consideró el estudio de Fishbein (1975 sobre el desarrollo del pensamiento probabilístico y el de Marzano (2000, relacionado con las dimensiones del aprendizaje. Estos elementos sirvieron para establecer el impacto del uso de los REA, en especial el de la plataforma Edmodo en el desarrollo de competencias en los estudiantes. Los instrumentos consistieron en una prueba de entrada, actividades de apoyo interactivo desde Edmodo y una prueba de salida para determinar los niveles de aprendizaje; mediante triangulación de datos, se evidenciaron alcances de niveles adecuados de desempeño acordes con los requerimientos de los estándares nacionales e internacionales.

The marginal social cost of headway for a scheduled service

DEFF Research Database (Denmark)

Fosgerau, Mogens

2009-01-01

waiting time costs as well as schedule delay costs measured relative to their desired time of arrival at the destination. They may either arrive at the station to choose just the next departure or they may plan for a specific departure in which case they incur also a planning cost. Then planning......This brief paper derives the marginal social cost of headway for a scheduled service, i.e. the cost for users of marginal increases to the time interval between departures. In brief we may call it the value of headway in analogy with the value of travel time and the value of reliability. Users have...... for a specific departure is costly but becomes more attractive at longer headways. Simple expressions for the user cost result. In particular, the marginal cost of headway is large at short headways and smaller at long headways. The difference in marginal costs is the value of time multiplied by half the headway....

Seismic Margin of 500MWe PFBR Beyond Safe Shutdown Earthquake

International Nuclear Information System (INIS)

Sajish, S.D.; Chellapandi, P.; Chetal, S.C.

2012-01-01

Summary: • Seismic design aspects of safety related systems and components of PFBR is discussed with a focus on reactor assembly components. • PFBR is situated in a low seismic area with a peak ground acceleration value of 0.156 g. • The design basis ground motion parameters for the seismic design are evaluated by deterministic method and confirmed by probabilistic seismic hazard analysis. • Review of the seismic design of various safety related systems and components indicate that margin is available to meet any demand due to an earthquake beyond SSE. • Reactor assembly vessels are the most critical components w.r.t seismic loading. • Minimum safety margin is 1.41 for plastic deformation and 1.46 against buckling. • From the preliminary investigation we come to the conclusion that PFBR can withstand an earthquake up to 0.22 g without violating any safety limits. • Additional margin can be estimated by detailed fragility analysis and seismic margin assessment methods

Late Cenozoic flexural deformation of the middle U.S. Atlantic passive margin

Science.gov (United States)

Pazzaglia, Frank J.; Gardner, Thomas, W.

1994-01-01

Despite the century-long recognition of regional epeirogeny along the middle Atlantic passive margin, relatively few studies have focused on understanding postrift uplift mechanisms. Here, we demonstrate that epeirogenic uplift of the central Appalachian Piedmont and subsidence of the Salisbury Embayment represent first-order, flexural isostatic processes driven by continental denudation and offshore deposition. Our results show that regional epeirogenic processes, present on all Atlantic-type passive margins, are best resolved by specific stratigraphic and geomorphic relationships, rather than topography. A simple one-dimensional geodynamic model, constrained by well-dated Baltimore Canyon trough, Coastal Plain, and lower Susquehanna River (piedmont) stratigraphy, simulates flexural deforamtion of the U.S. Atlantic margin. The model represents the passive margin lithosphree as a uniformly thick elastic plate, without horizontal compressive stresses, that deforms flexurally under the stress of strike-averaged, vertically applied line loads. Model results illustrate a complex interaction among margin stratigraphy and geomorphology, the isostatic repsonse to denudational and depositional processes, and the modulating influence of exogenic forces such as eustasy. The current elevation, with respect to modern sea level, of fluvial terraces and correlateive Coastal Plain deposits or unconformities is successfully predicted through the synthesis of paleotopography, eustatic change, and margin flexure. Results suggest that the middle U.S. Atlantic margin landward of East Coast Magnetic Anomaly is underlain by lithoshpere with an average elastic thickness of 40 km (flexural rigidity, D = 4 X 10(exp 23) N m), the margin experience an average, long-term denudation rate of approximately 10m/m.y., and the Piedmont has been flexurally upwaped between 35 and 130 meters in the last 15 m.y. Long term isostatic continental uplift resulting rom denudation and basin subsidence

Long-term outcome for gastric marginal zone lymphoma treated with radiotherapy

DEFF Research Database (Denmark)

Wirth, A; Gospodarowicz, M; Aleman, B M P

2013-01-01

We evaluated the long-term results of radiotherapy for patients with gastric marginal zone lymphoma (GMZL).......We evaluated the long-term results of radiotherapy for patients with gastric marginal zone lymphoma (GMZL)....

Energy system analyses of the marginal energy technology in life cycle assessments

DEFF Research Database (Denmark)

Mathiesen, B.V.; Münster, Marie; Fruergaard, Thilde

2007-01-01

in historical and potential future energy systems. Subsequently, key LCA studies of products and different waste flows are analysed in relation to the recom- mendations in consequential LCA. Finally, a case of increased waste used for incineration is examined using an energy system analysis model......In life cycle assessments consequential LCA is used as the “state-of-the-art” methodology, which focuses on the consequences of decisions made in terms of system boundaries, allocation and selection of data, simple and dynamic marginal technology, etc.(Ekvall & Weidema 2004). In many LCA studies...... marginal technology? How is the marginal technology identified and used today? What is the consequence of not using energy system analy- sis for identifying the marginal energy technologies? The use of the methodology is examined from three angles. First, the marginal electricity technology is identified...

Confinement margins for ignition and driven operation in Iter Eda ID

International Nuclear Information System (INIS)

Johner, J.

1995-09-01

Preliminary calculations for ITER EDA ID have been performed using the 1/2D thermal equilibrium code HELIOS. It is found that: - The maximum ignition margin for ITER ID (29%) is 6% less than for ITER OD (35%) and 5% less than for ITER CDA (34%). - Decreasing the ration τ * He /τ E from the nominal value 10 to a value of 5 gives a 12% gain in the maximum ignition margin. Increasing the ration from 10 to 15 causes a 22% loss in the margin. Furthermore, ignited equilibria non longer exist for τ * He /τ E ≥ 17.6. - Operation in driven mode with 50 MW of external power increases the confinement capability by 13%. With 100 MW, the improvement is 24%. - Lowering the fusion power from 1500 to 1000 MW slightly improves the maximum ignition margin (+5%) and allows operation below the Greenwald density limit. - A 10% reduction of the toroidal magnetic field with a correlative diminution of the plasma current for constant safety factor operation, causes a dramatic reduction (-18%) of the maximum ignition margin. - A fraction of neon of 0.68% would completely suppress the ignition margin. Furthermore, ignited equilibria, with the nominal fusion power and τ * He /τ E , no longer exist when the neon fraction exceeds 0.75%. (Author). 2 refs., 10 figs

Anticipation and the adaptive control of safety margins in driving

NARCIS (Netherlands)

van der Hulst, M.; Meijman, T.F.; Rothengatter, J.A.

Driving is a task that requires the timely detection of critical events and relevant changes in traffic circumstances. Adaptation of speed and safety margins allows drivers to control the time available to react to potential hazards. One of the basic safety margins in driving is the time headway

Significance of post-resection tissue shrinkage on surgical margins of oral squamous cell carcinoma.

Science.gov (United States)

El-Fol, Hossam Abdelkader; Noman, Samer Abduljabar; Beheiri, Mohamed Galal; Khalil, Abdalla M; Kamel, Mahmoud Mohamed

2015-05-01

Resecting oral squamous cell carcinoma (SCC) with an appropriate margin of uninvolved tissue is critical in preventing local recurrence and in making decisions regarding postoperative radiation therapy. This task can be difficult due to the discrepancy between margins measured intraoperatively and those measured microscopically by the pathologist after specimen processing. A total of 61 patients underwent resective surgery with curative intent for primary oral SCC were included in this study. All patients underwent resection of the tumor with a measured 1-cm margin. Specimens were then submitted for processing and reviewing, and histopathologic margins were measured. The closest histopathologic margin was compared with the in situ margin (1 cm) to determine the percentage discrepancy. The mean discrepancy between the in situ margins and the histopathological margins of all close and positive margins were 47.6% for the buccal mucosa (with a P value corresponding to 0.05 equaling 2.1), which is statistically significant, 4.8% for the floor of mouth, 9.5% for the mandibular alveolus, 4.8% for the retromolar trigon, and 33.3% for the tongue. There is a significant difference among resection margins based on tumor anatomical location. Margins shrinkage after resection and processing should be considered at the time of the initial resection. Tumors located in the buccal mucosa show significantly greater discrepancies than tumors at other sites. These findings suggest that it is critical to consider the oral site when outlining margins to ensure adequacy of resection. Buccal SCC is an aggressive disease, and should be considered as an aggressive subsite within the oral cavity, requiring a radical and aggressive resective approach. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Marginal adaptation of four inlay casting waxes on stone, titanium, and zirconia dies.

Science.gov (United States)

Michalakis, Konstantinos X; Kapsampeli, Vassiliki; Kitsou, Aikaterini; Kirmanidou, Yvone; Fotiou, Anna; Pissiotis, Argirios L; Calvani, Pasquale Lino; Hirayama, Hiroshi; Kudara, Yukio

2014-07-01

Different inlay casting waxes do not produce copings with satisfactory marginal accuracy when used on different die materials. The purpose of this study was to evaluate the marginal accuracy of 4 inlay casting waxes on stone dies and titanium and zirconia abutments and to correlate the findings with the degree of wetting between the die specimens and the inlay casting waxes. The inlay casting waxes tested were Starwax (Dentaurum), Unterziehwachs (Bredent), SU Esthetic wax (Schuler), and Sculpturing wax (Renfert). The marginal opening of the waxes was measured with a stereomicroscope on high-strength stone dies and on titanium and zirconia abutments. Photographic images were obtained, and the mean marginal opening for each specimen was calculated. A total of 1440 measurements were made. Wetting between die materials and waxes was determined after fabricating stone, titanium, and zirconia rectangular specimens. A calibrated pipette was used to place a drop of molten wax onto each specimen. The contact angle was calculated with software after an image of each specimen had been made with a digital camera. Collected data were subjected to a 2-way analysis of variance (α=.05). Any association between marginal accuracy and wetting of different materials was found by using the Pearson correlation. The wax factor had a statistically significant effect both on the marginal discrepancy (F=158.31, P<.001) and contact angle values (F=68.09, P<.001). A statistically significant effect of the die material factor both on the marginal adaptation (F=503.47, P<.001) and contact angle values (F=585.02, P<.001) was detected. A significant correlation between the marginal accuracy and the contact angle values (Pearson=0.881, P=.01) was also found. Stone dies provided wax copings with the best marginal integrity, followed by titanium and zirconia abutments. Unterziehwachs (Bredent), wax produced the best marginal adaptation on different die materials. A significant correlation was found

Marginal zone in femoral head avascular necrosis: scintigraphic characteristics and clinical prognostic value

International Nuclear Information System (INIS)

Milcinski, M.; Sedonja, I.; Dolinar, D.; Jevtic, V.

2002-01-01

Aim: Marginal zone, seen on magnetic resonance imaging (MRI) in femoral head avascular necrosis, consists of granulation tissue and sclerosis at the junction of necrotic and normal bone. Prognostic value of this finding is not clear. Aim of our study was to evaluate osteoblastic activity of marginal zone with bone scintigraphy and to assess prognostic importance of marginal zone for further evolution of femoral head necrosis. Material and methods: MRI was performed in 37 hips in 26 patients (17 m, 9 f, 20-64 y, mean 42,9 y) with Ficat 0-II avascular necrosis (SE T1W, STIR and SE T1W FAT.SAT after Gd DTPA in the coronal plane and GE FLASH in the sagittal plane). In 26 hips of 17 patients planar and pinhole scintigraphy with 99mTc-DPD was performed. Results: On MRI, marginal zone divided necrotic and normal bone in 26/37 (70,3%) hips, in 14/26 it was thin (2% of femoral head diameter or less), but in 12/26 it was wide (more than 2% of femoral head diameter). In 11/37 (29,7%) hips marginal zone was not seen. Pinhole scintigraphy was performed in 26 hips; in all 10/10 (100%) hips with wide marginal zone, seen on MRI, increased osteoblastic activity was detected, while only in 1/9 (11,1%) hips with thin marginal zone on MRI osteoblastic activity was increased. Patients were followed 1 to 5 years (mean 2,2 y). In hips without marginal zone no collapse of femoral head was seen until now, in 2/11 (18,2%) femoral heads MRI and clinical regression was observed. Ten of 12 lesions with wide marginal zone (83,3 %) collapsed 0,25 to 2,5 (mean 1) years after onset of pain. Two of 12 lesions with wide marginal zone (16,7%) have not collapsed until now. From lesions with thin marginal zone, 4/14 (28,6 %) collapsed 0,7 to 3 (mean 1,9) years after onset of pain, 10/14 (71,4%) did not collapse until now. Conclusion: Increased osteoblastic activity in wide marginal zone between necrotic and vital bone in hip avascular necrosis is bad prognostic factor for femoral head collapse

In vitro evaluation of the marginal fit of different all-ceramic crowns

Directory of Open Access Journals (Sweden)

Munir Tolga Yucel

2013-09-01

Conclusion: In-Ceram all-ceramic crowns showed the largest marginal gap, and Celay crowns showed the smallest marginal gap in both die groups. The marginal discrepancies found in this study were all within the clinically acceptable standard of 120 μm.

Calculo y comparacion de la prima de un reaseguro de salud usando el modelo de opciones de Black-Scholes y el modelo actuarial

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Luis Eduardo Giron

2015-12-01

Full Text Available La presente investigación pretende calcular y comparar la prima de un reaseguro  usando el modelo de opciones de Black-Scholes y el modelo clásico actuarial tradicional. El período de análisis va desde enero de 2011 hasta diciembre de 2012. Los resultados obtenidos muestran que el modelo de Black-Scholes, que se utiliza normalmente para valorar opciones financieras, puede ser también usado para la estimación de primas de reaseguros de salud; y que la prima neta estimada a partir de este modelo se aproxima a las establecidas por el método actuarial, excepto cuando el deducible del reaseguro es muy alto (por encima de $200.000.000.

Surgical Margins and the Risk of Local-Regional Recurrence After Mastectomy Without Radiation Therapy

International Nuclear Information System (INIS)

Childs, Stephanie K.; Chen Yuhui; Duggan, Margaret M.; Golshan, Mehra; Pochebit, Stephen; Wong, Julia S.; Bellon, Jennifer R.

2012-01-01

Purpose: Although positive surgical margins are generally associated with a higher risk of local-regional recurrence (LRR) for most solid tumors, their significance after mastectomy remains unclear. We sought to clarify the influence of the mastectomy margin on the risk of LRR. Methods and Materials: The retrospective cohort consisted of 397 women who underwent mastectomy and no radiation for newly diagnosed invasive breast cancer from 1998-2005. Time to isolated LRR and time to distant metastasis (DM) were evaluated by use of cumulative-incidence analysis and competing-risks regression analysis. DM was considered a competing event for analysis of isolated LRR. Results: The median follow-up was 6.7 years (range, 0.5-12.8 years). The superficial margin was positive in 41 patients (10%) and close (≤2 mm) in 56 (14%). The deep margin was positive in 23 patients (6%) and close in 34 (9%). The 5-year LRR and DM rates for all patients were 2.4% (95% confidence interval, 0.9-4.0) and 3.5% (95% confidence interval, 1.6-5.3) respectively. Fourteen patients had an LRR. Margin status was significantly associated with time to isolated LRR (P=.04); patients with positive margins had a 5-year LRR of 6.2%, whereas patients with close margins and negative margins had 5-year LRRs of 1.5% and 1.9%, respectively. On univariate analysis, positive margins, positive nodes, lymphovascular invasion, grade 3 histology, and triple-negative subtype were associated with significantly higher rates of LRR. When these factors were included in a multivariate analysis, only positive margins and triple-negative subtype were associated with the risk of LRR. Conclusions: Patients with positive mastectomy margins had a significantly higher rate of LRR than those with a close or negative margin. However, the absolute risk of LRR in patients with a positive surgical margin in this series was low, and therefore the benefit of postmastectomy radiation in this population with otherwise favorable features

A comparison of the marginal fit of In-Ceram, IPS Empress, and Procera crowns.

Science.gov (United States)

Sulaiman, F; Chai, J; Jameson, L M; Wozniak, W T

1997-01-01

The in vitro marginal fit of three all-ceramic crown systems (In-Ceram, Procera, and IPS Empress) was compared. All crown systems were significantly different from each other at P = 0.05. In-Ceram exhibited the greatest marginal discrepancy (161 microns), followed by Procera (83 microns), and IPS Empress (63 microns). There were no significant differences among the various stages of the crown fabrication: core fabrication, porcelain veneering, and glazing. The facial and lingual margins exhibited significantly larger marginal discrepancies than the mesial and distal margins.

Talking (and Not Talking) about Race, Social Class and Dis/Ability: Working Margin to Margin

Science.gov (United States)

Ferri, Beth A.; Connor, David J.

2014-01-01

In this article we examine some of the omnipresent yet unacknowledged discourses of social and economic disadvantage and dis/ability within schools in the US. First, we document ways that social class, race, and dis/ability function within schools to further disadvantage and exclude already marginalized students. Next, we show how particular ways…

A Semiparametric Marginalized Model for Longitudinal Data with Informative Dropout

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Mengling Liu

2012-01-01

Full Text Available We propose a marginalized joint-modeling approach for marginal inference on the association between longitudinal responses and covariates when longitudinal measurements are subject to informative dropouts. The proposed model is motivated by the idea of linking longitudinal responses and dropout times by latent variables while focusing on marginal inferences. We develop a simple inference procedure based on a series of estimating equations, and the resulting estimators are consistent and asymptotically normal with a sandwich-type covariance matrix ready to be estimated by the usual plug-in rule. The performance of our approach is evaluated through simulations and illustrated with a renal disease data application.

Advancing Understanding of Earthquakes by Drilling an Eroding Convergent Margin

Science.gov (United States)

von Huene, R.; Vannucchi, P.; Ranero, C. R.

2010-12-01

A program of IODP with great societal relevance is sampling and instrumenting the seismogenic zone. The zone generates great earthquakes that trigger tsunamis, and submarine slides thereby endangering coastal communities containing over sixty percent of the earth’s population. To asses and mitigate this endangerment it is urgent to advance understanding of fault dynamics that allows more timely anticipation of hazardous seismicity. Seismogenesis on accreting and eroding convergent plate boundaries apparently differ because of dissimilar materials along the interplate fault. As the history of instrumentally recorded earthquakes expands the difference becomes clearer. The more homogeneous clay, silt and sand subducted at accreting margins is associated with great earthquakes (M 9) whereas the fragmented upper plate rock that can dominate subducted material along an eroding margin plate interface is associated with many tsunamigenic earthquakes (Bilek, 2010). Few areas have been identified where the seismogenic zone can be reached with scientific drilling. In IODP accreting margins are studied on the NanTroSeize drill transect off Japan where the ultimate drilling of the seismogenic interface may occur by the end of IODP. The eroding Costa Rica margin will be studied in CRISP where a drill program will begin in 2011. The Costa Rican geophysical site survey will be complete with acquisition and processing of 3D seismic data in 2011 but the entire drilling will not be accomplished in IODP. It is appropriate that the accreting margin study be accomplished soon considering the indications of a pending great earthquake that will affect a country that has devoted enormous resources to IODP. However, understanding the erosional end-member is scientifically as important to an understanding of fault mechanics. Transoceanic tsunamis affect the entire Pacific rim where most subduction zones are eroding margins. The Costa Rican subduction zone is less complex operationally and

The Role of Field Margins in Agro-biodiversity Management at the Farm Level

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Giulio Lazzerini

2007-06-01

Full Text Available The agroecosystem could be considered as a mosaic so large to involve fields with annual and perennial crops, pastures, spots of wildwood, semi-natural habitats, vegetation in the edges of fields. In the agroecosystem these ecological infrastructures have a positive effects on the crops because of the exchange among community of organisms, materials and energy. The aim of this research is to evaluate the effects of field margins on some biodiversity components (plant species and carabid beetles of four farms located in Val d’Orcia (Tuscany. We compared three types of field margins: 1. Cultivated margin strips; 2. Sown grass margin strips; 3. Wild margin strips with hedgerow. In a very simplified typology of farming system, like the one studied (Val d’Orcia, the presence of field margins (hedges, margin strips and semi-natural habitats associated with the boundary is very important for its ecological effects: it improves the planned biodiversity, gives habitat, refuge, food and corridors for the movement to the different species of organisms in the area. Applying the multivariate analysis to the experimental data, we can notice a positive effect of the presence of field margins on the trend of both components of biodiversity. This positive effect, which support the mechanisms of autoregulation of the agroecosystems, is very important especially for organic and biodynamic agriculture, where the use of pesticides is not allowed.

Research on the margin of futures markets and the policy spillover effect

Institute of Scientific and Technical Information of China (English)

Difang Wan; Yang Yang; Dong Fang; Guang Yang

2011-01-01

Purpose-The purpose of this paper is to investigate whether the change of margin in Chinese futures markets has policy spillover effects.Design/methodology/approach-The paper constructs a model based on Harzmark and on Chng,taking Chinese futures markets status quo as a single species and restrictions on foreign investment into consideration,introduces the assumptions of spillover effect of speculators,then obtains investor's demand function.Subsequently,the effects of Shanghai Futures Exchange's 11 instances of margin changing are analyzed.Findings-The paper finds that in the Chinese futures market,margin changing has impact on the open interest (OI) and the speculator spillover effect is validated.Research limitations/implications-The irrational behavior of investors in markets is not taken into account in the model and data about spillover speculators were not directly available.Originality/value-The paper usefully analyzes the effects of the Shanghai Futures Exchange's 11 instances of margin changing from 2000 to 2007 and examines the actual effects of margin-changing policy,in the views of OI,trading volume and the externality,the results showing that margin changing has impact on investor structure and validates the existence of the assumed speculator spillover effect.

PENDIDIKAN ALTERNATIF UNTUK PEREMPUAN MARGINAL DI PEDESAAN

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Ratnawati Tahir

2011-11-01

Full Text Available Abstract: Alternative Education for Marginalized Women in Rural Areas. The study aims to find alter­native forms of education for marginalized women, the process of forming study groups and gender based learning process that serves the center of the development of education, leadership and a source of economic empowerment. The study uses qualitative methods, involving a group of women who have attended an al­ternative education. Researchers and informants from community leaders. The results showed that the form of alternative education is a method of adult education or andragogy. Study groups consisted of basic literacy and functional literacy. The learning process begins with the sharing of learning, reflection on life experience and role play method. The result is 65% of participants have increased the ability of reading, writing and numeracy, and understanding of the issues of women who have confidence in the decision making of households and communities. Abstrak: Pendidikan Alternatif untuk Perempuan Marginal di Pedesaan. Penelitian ini bertujuan mengetahui bentuk pendidikan alternatif untuk perempuan marginal, proses pembentukan kelompok belajar, dan proses pembelajaran berperspektif gender yang berfungsi menjadi pusat pengembangan pendidikan, kepemimpinan, dan sumber penguatan ekonomi. Penelitian menggunakan metode kualitatif, mengambil satu kelompok perempuan yang telah mengikuti pendidikan alternatif. Informan terdiri atas tokoh masyarakat, seperti Kepala Desa, Ketua RT/RW, dan ibu rumah tangga. Hasil penelitian menunjukkan bahwa bentuk pembelajaran pendidikan alternatif adalah metode pendidikan orang dewasa atau andragogy. Pembentukan kelompok belajar terdiri atas; kelompok baca tulis dan keaksaraan fungsional. Proses pembe­lajaran dimulai dengan sharing pembelajaran, refleksi pengalaman hidup, dan metode role play. Hasilnya 65% peserta pembelajaran mengalami peningkatan kemampuan membaca, menulis, dan berhitung, serta pema

Evaluación tomográfica y radiográfica de la obturación radicular tridimensional de conductos radiculares únicos tratados con tres técnicas de obturación radicular: Estudio in Vitro

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Mónica Alexandra Pavón Granja

2016-09-01

Full Text Available El principal reto durante la terapia endodóntica es la obturación radicular, considerada como fase crítica ya que de esta va a depender el éxito o el fracaso. Por varios años se ha investigado tanto materiales como técnicas que permitan el sellado hermético tridimensional del sistema de conductos radiculares, biocompatibilidad que permita la adecuada reparación de los tejidos periapicales y que la obturación se mantenga con el tiempo proporcionando salud. Objetivo: Evaluar la adaptación tridimensional de tres técnicas de obturación radicular definitiva a nivel del tercio apical de conductos radiculares únicos. Materiales y métodos: Estudio de tipo experimental y aleatorizado, la muestra fue de 42 raíces de dientes uniradiculares divididos en 3 grupos de estudio (n=14, previamente se realizó un registro radiográfico periapical digital de toda la muestra posteriormente fueron instrumentados con técnica hibrida, desinfectados con NaOCl al 5,25% + activación ultrasónica y EDTA al 17%, GA fue sometido a técnica de obturación lateral en frío, GB aplicado técnica de obturación termomecánica McSpadden y GC se obturó con técnica termoplastificada (BeFill-VDW. Resultados: Los grupos C y B observados a través de tomografía computarizada presentaron mejores resultados de obturación radicular que el grupo A que no presentó un buen sellado apical, sin embargo, en el grupo C se observó mejores resultados que en A y B Conclusiones: Las técnicas de obturación radicular definitivas con la técnica termoplastificada mostraron ser ideales para proporcionar un sellado apical hermético durante el tratamiento endodóntico en la fase de obturación

Stability of marginally outer trapped surfaces and symmetries

Energy Technology Data Exchange (ETDEWEB)

Carrasco, Alberto; Mars, Marc, E-mail: acf@usal.e, E-mail: marc@usal.e [Facultad de Ciencias, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca (Spain)

2009-09-07

We study the properties of stable, strictly stable and locally outermost marginally outer trapped surfaces in spacelike hypersurfaces of spacetimes possessing certain symmetries such as isometries, homotheties and conformal Killings. We first obtain results for general diffeomorphisms in terms of the so-called metric deformation tensor and then particularize to different types of symmetries. In particular, we find restrictions at the surfaces on the vector field generating the symmetry. Some consequences are discussed. As an application, we present a result on non-existence of stable marginally outer trapped surfaces in slices of FLRW.

Manipulating field margins to increase predation intensity in fields of winter wheat (Triticum eastivum)

DEFF Research Database (Denmark)

Mansion-Vaquie, Agathe; Ferrante, Marco; Cook, S M

2017-01-01

, intraguild predation, hyperparasitism) may complicate the assumption that a higher density of natural enemies would increase the level of biological control. We investigated the natural enemy guild composition and the predation rate along flower vs. grass margins at the edge of winter wheat (Triticum...... to the two margin types: specialists (mostly parasitic wasps) were attracted by the flower margins, while generalists (ground beetles, rove beetles and spiders) were more active in grass margins. The number of artificial caterpillars attacked was significantly greater in grass margins (mean = 48.9%, SD = 24...

Passive target tracking using marginalized particle filter

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A marginalized particle filtering(MPF)approach is proposed for target tracking under the background of passive measurement.Essentially,the MPF is a combination of particle filtering technique and Kalman filter.By making full use of marginalization,the distributions of the tractable linear part of the total state variables are updated analytically using Kalman filter,and only the lower-dimensional nonlinear state variable needs to be dealt with using particle filter.Simulation studies are performed on an illustrative example,and the results show that the MPF method leads to a significant reduction of the tracking errors when compared with the direct particle implementation.Real data test results also validate the effectiveness of the presented method.

Analytic solutions for marginal deformations in open superstring field theory

International Nuclear Information System (INIS)

Okawa, Y.

2007-04-01

We extend the calculable analytic approach to marginal deformations recently developed in open bosonic string field theory to open superstring field theory formulated by Berkovits. We construct analytic solutions to all orders in the deformation parameter when operator products made of the marginal operator and the associated superconformal primary field are regular. (orig.)

Marginalized Youth. An Introduction.

OpenAIRE

Kessl, Fabian; Otto, Hans-Uwe

2009-01-01

The life conduct of marginalized groups has become subject to increasing levels of risk in advanced capitalist societies. In particular, children and young people are confronted with the harsh consequences of a “new poverty” in the contemporary era. The demographic complexion of today’s poverty is youthful, as a number of government reports have once again documented in recent years in Australia, Germany, France, Great Britain, the US or Scandinavian countries. Key youth studies have shown a ...

Regional Marginal Abatement Cost Curves for NOx

Data.gov (United States)

U.S. Environmental Protection Agency — Data underlying the figures included in the manuscript "Marginal abatement cost curve for NOx incorporating controls, renewable electricity, energy efficiency and...

Maximización de la función de Verosimilitud de Distribuciones de Probabilidad usando Algoritmos Genéticos

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Oscar Arturo Fuentes Mariles

2015-01-01

Full Text Available Tradicionalmente, para obtener los parámetros de una función de distribución con el método de máxima verosimilitud se acostumbra igualar a cero la derivada del logaritmo de la función de verosimilitud y resolver el sistema de ecuaciones no lineales que resulta. La popularidad del procedimiento se debe a su sencillez; sin embargo, cuando la función de verosimilitud no es suficientemente regular, puede llevar a obtener un valor muy alejado del máximo Por ese motivo, en este documento se presenta el uso de un algoritmo genético que permite encontrar los parámetros de la función de distribución (con los que se maximiza directamente la función de verosimilitud, o su logaritmo, sin recurrir a la derivada de los logaritmos de dicha función. Se halló buena concordancia de los resultados respecto a los obtenidos usando un software de uso frecuente en México, para el caso las funciones Gumbel y Gumbel de dos poblaciones. 

Variability of the geothermal gradient across two differently aged magma-rich continental rifted margins of the Atlantic Ocean: the Southwest African and the Norwegian margins

Science.gov (United States)

Gholamrezaie, Ershad; Scheck-Wenderoth, Magdalena; Sippel, Judith; Strecker, Manfred R.

2018-02-01

The aim of this study is to investigate the shallow thermal field differences for two differently aged passive continental margins by analyzing regional variations in geothermal gradient and exploring the controlling factors for these variations. Hence, we analyzed two previously published 3-D conductive and lithospheric-scale thermal models of the Southwest African and the Norwegian passive margins. These 3-D models differentiate various sedimentary, crustal, and mantle units and integrate different geophysical data such as seismic observations and the gravity field. We extracted the temperature-depth distributions in 1 km intervals down to 6 km below the upper thermal boundary condition. The geothermal gradient was then calculated for these intervals between the upper thermal boundary condition and the respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal boundary condition). According to our results, the geothermal gradient decreases with increasing depth and shows varying lateral trends and values for these two different margins. We compare the 3-D geological structural models and the geothermal gradient variations for both thermal models and show how radiogenic heat production, sediment insulating effect, and thermal lithosphere-asthenosphere boundary (LAB) depth influence the shallow thermal field pattern. The results indicate an ongoing process of oceanic mantle cooling at the young Norwegian margin compared with the old SW African passive margin that seems to be thermally equilibrated in the present day.

A method of accurate determination of voltage stability margin

Energy Technology Data Exchange (ETDEWEB)

Wiszniewski, A.; Rebizant, W. [Wroclaw Univ. of Technology, Wroclaw (Poland); Klimek, A. [AREVA Transmission and Distribution, Stafford (United Kingdom)

2008-07-01

In the process of developing power system disturbance, voltage instability at the receiving substations often contributes to deteriorating system stability, which eventually may lead to severe blackouts. The voltage stability margin at receiving substations may be used to determine measures to prevent voltage collapse, primarily by operating or blocking the transformer tap changing device, or by load shedding. The best measure of the stability margin is the actual load to source impedance ratio and its critical value, which is unity. This paper presented an accurate method of calculating the load to source impedance ratio, derived from the Thevenin's equivalent circuit of the system, which led to calculation of the stability margin. The paper described the calculation of the load to source impedance ratio including the supporting equations. The calculation was based on the very definition of voltage stability, which says that system stability is maintained as long as the change of power, which follows the increase of admittance is positive. The testing of the stability margin assessment method was performed in a simulative way for a number of power network structures and simulation scenarios. Results of the simulations revealed that this method is accurate and stable for all possible events occurring downstream of the device location. 3 refs., 8 figs.

Marginal Consistency: Upper-Bounding Partition Functions over Commutative Semirings.

Science.gov (United States)

Werner, Tomás

2015-07-01

Many inference tasks in pattern recognition and artificial intelligence lead to partition functions in which addition and multiplication are abstract binary operations forming a commutative semiring. By generalizing max-sum diffusion (one of convergent message passing algorithms for approximate MAP inference in graphical models), we propose an iterative algorithm to upper bound such partition functions over commutative semirings. The iteration of the algorithm is remarkably simple: change any two factors of the partition function such that their product remains the same and their overlapping marginals become equal. In many commutative semirings, repeating this iteration for different pairs of factors converges to a fixed point when the overlapping marginals of every pair of factors coincide. We call this state marginal consistency. During that, an upper bound on the partition function monotonically decreases. This abstract algorithm unifies several existing algorithms, including max-sum diffusion and basic constraint propagation (or local consistency) algorithms in constraint programming. We further construct a hierarchy of marginal consistencies of increasingly higher levels and show than any such level can be enforced by adding identity factors of higher arity (order). Finally, we discuss instances of the framework for several semirings, including the distributive lattice and the max-sum and sum-product semirings.

Constraints Imposed by Rift Inheritance on the Compressional Reactivation of a Hyperextended Margin: Mapping Rift Domains in the North Iberian Margin and in the Cantabrian Mountains

Science.gov (United States)

Cadenas, P.; Fernández-Viejo, G.; Pulgar, J. A.; Tugend, J.; Manatschal, G.; Minshull, T. A.

2018-03-01

The Alpine Pyrenean-Cantabrian orogen developed along the plate boundary between Iberia and Europe, involving the inversion of Mesozoic hyperextended basins along the southern Biscay margin. Thus, this margin represents a natural laboratory to analyze the control of structural rift inheritance on the compressional reactivation of a continental margin. With the aim to identify former rift domains and investigate their role during the subsequent compression, we performed a structural analysis of the central and western North Iberian margin, based on the interpretation of seismic reflection profiles and local constraints from drill-hole data. Seismic interpretations and published seismic velocity models enabled the development of crustal thickness maps that helped to constrain further the offshore and onshore segmentation. Based on all these constraints, we present a rift domain map across the central and western North Iberian margin, as far as the adjacent western Cantabrian Mountains. Furthermore, we provide a first-order description of the margin segmentation resulting from its polyphase tectonic evolution. The most striking result is the presence of a hyperthinned domain (e.g., Asturian Basin) along the central continental platform that is bounded to the north by the Le Danois High, interpreted as a rift-related continental block separating two distinctive hyperextended domains. From the analysis of the rift domain map and the distribution of reactivation structures, we conclude that the landward limit of the necking domain and the hyperextended domains, respectively, guide and localize the compressional overprint. The Le Danois block acted as a local buttress, conditioning the inversion of the Asturian Basin.

Circumferential scouting punch biopsies to delineate surgical margin for dermatofibrosarcoma protuberans

Directory of Open Access Journals (Sweden)

Tsung-Mao Huang

2012-03-01

Full Text Available Dermatofibrosarcoma protuberans (DFSP is an uncommon soft-tissue tumor involving the dermis and subcutaneous tissue with a high local recurrence rate after standard excision. Mohs micrographic surgery offers a lower recurrence rate. However, the procedure requires multiple stages of excision with intraoperative histopathological mapping, which is time consuming and expensive. We report our experience of using circumferential scouting punch biopsy technique in five patients to determine in advance the resection margins for DFSP prior to wide excision. Multiple 4 mm punches, usually eight in number, were performed 1–2.5 cm around the palpable borders of DFSP to delineate the resection margins in five consecutive patients. Tumors were excised at a later date along the margin defined by these biopsies and the wounds were repaired with skin graft. The operation was completed in 2 hours in all cases excluding one that required frozen sections for deep margin. No recurrence was noted 2–10 years after the operations. The results suggest that circumferential scouting punch biopsies before wide excision may be an alternative method to define the resection margins for DFSP when Mohs surgery is not available.

Wintertime pytoplankton bloom in the Subarctic Pacific supportedby continental margin iron

Energy Technology Data Exchange (ETDEWEB)

Lam, Phoebe J.; Bishop, James K.B.; Henning, Cara C.; Marcus,Matthew A.; Waychunas, Glenn A.; Fung, Inez

2004-06-08

Heightened biological activity was observed in February 1996in the high-nutrient low-chlorophyll (HNLC) subarctic North PacificOcean, a region that is thought to beiron-limited. Here we provideevidence supporting the hypothesis that Ocean Station Papa (OSP) in thesubarctic Pacific received a lateral supply of particulate iron from thecontinental margin off the Aleutian Islands in the winter, coincidentwith the observed biological bloom. Synchrotron X-ray analysis was usedto describe the physical form, chemistry, and depth distributions of ironin size fractionated particulate matter samples. The analysis revealsthat discrete micron-sized iron-rich hotspots are ubiquitous in the upper200m at OSP, more than 900km from the closest coast. The specifics of thechemistry and depth profiles of the Fe hot spots trace them to thecontinental margins. We thus hypothesize that iron hotspots are a markerfor the delivery of iron from the continental margin. We confirm thedelivery of continental margin iron to the open ocean using an oceangeneral circulation model with an iron-like tracer source at thecontinental margin. We suggest that iron from the continental marginstimulated a wintertime phytoplankton bloom, partially relieving the HNLCcondition.

Model-Based Systems Engineering Approach to Managing Mass Margin

Science.gov (United States)

Chung, Seung H.; Bayer, Todd J.; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Christopher; Lam, Doris

2012-01-01

When designing a flight system from concept through implementation, one of the fundamental systems engineering tasks ismanaging the mass margin and a mass equipment list (MEL) of the flight system. While generating a MEL and computing a mass margin is conceptually a trivial task, maintaining consistent and correct MELs and mass margins can be challenging due to the current practices of maintaining duplicate information in various forms, such as diagrams and tables, and in various media, such as files and emails. We have overcome this challenge through a model-based systems engineering (MBSE) approach within which we allow only a single-source-of-truth. In this paper we describe the modeling patternsused to capture the single-source-of-truth and the views that have been developed for the Europa Habitability Mission (EHM) project, a mission concept study, at the Jet Propulsion Laboratory (JPL).

Pathologic margin involvement and the risk of recurrence in patients treated with breast-conserving therapy

International Nuclear Information System (INIS)

Gage, Irene; Nixon, Asa J.; Schnitt, Stuart J.; Recht, Abram; Gelman, Rebecca; Silver, Barbara; Connolly, James L.; Harris, Jay R.

1995-01-01

PURPOSE: To assess the relationship between microscopic margin status and recurrence after breast-conserving therapy for tumors with or without an extensive intraductal component (EIC). MATERIALS AND METHODS: During the years 1968 to 1986, 1865 women with unilateral clinical stage I or II breast cancer were treated with radiation therapy for breast conservation. Of these, 340 received ≥60 Gy to the tumor bed and had margins that were evaluable on review of their pathologic slides; these constitute the study population. The median follow-up was 109 months. All available slides were reviewed by one of the study pathologists (SS, JC). Final radial margins of excision were classified as negative >1 mm (no invasive or ductal carcinoma in-situ within 1 mm of the inked margin), negative ≤1 mm (any carcinoma ≤1 mm of the inked margin but not at ink) or positive (any carcinoma at the inked margin). A focally positive margin was defined as any invasive or in-situ carcinoma at the margin in ≤3 LPF. The extent of positivity was not evaluable in 2 patients and the distance of the tumor from the margin was not evaluable in 48 patients with a negative margin. Thirty-nine percent of EIC-negative and 46% of EIC-positive patients underwent a re-excision and, for these, the final margin analyzed was from the re-excised specimen. The median dose to the tumor bed was 63 Gy for patients with positive margins and 62 Gy for patients with negative margins. Recurrent disease was classified as ipsilateral breast recurrence (IBR) or distant metastasis/regional nodal failure (DM/RNF). RESULTS: Five year crude rates for the first site of recurrence were calculated for 340 patients evaluable at 5 years. Results were tabulated separately for all patients, EIC-negative and EIC-positive. All p-values tested for differences in the distribution of sites of first failure. CONCLUSIONS: The risk of ipsilateral breast recurrence is equally low for patients with close (≤1 mm) or negative (>1 mm

Evaluation of seismic margins for an in-plant piping system

International Nuclear Information System (INIS)

Kot, C.A.; Srinivasan, M.G.; Hsieh, B.J.

1991-01-01

Earthquake experience as well as experiments indicate that, in general, piping systems are quite rugged in resisting seismic loadings. Therefore there is a basis to hold that the seismic margin against pipe failure is very high for systems designed according to current practice. However, there is very little data, either from tests or from earthquake experience, on the actual margin or excess capacity (against failure from seismic loading) of in-plant piping systems. Design of nuclear power plant piping systems in the US is governed by the criteria given in the ASME Boiler and Pressure Vessel (B ampersand PV) Code, which assure that pipe stresses are within specified allowable limits. Generally linear elastic analytical methods are used to determine the stresses in the pipe and forces in pipe supports. The objective of this study is to verify that piping designed according to current practice does indeed have a large margin against failure and to quantify the excess capacity for piping and dynamic pipe supports on the basis of data obtained in a series of high-level seismic experiments (designated SHAM) on an in-plant piping system at the HDR (Heissdampfreaktor) Test Facility in Germany. Note that in the present context, seismic margin refers to the deterministic excess capacities of piping or supports compared to their design capacities. The excess seismic capacities or margins of a prototypical in-plant piping system and its components are evaluated by comparing measured inputs and responses from high-level simulated seismic experiments with design loads and allowables. Large excess capacities are clearly demonstrated against pipe and overall system failure with the lower bound being about four. For snubbers the lower bound margin is estimated at two and for rigid strut supports at five. 4 refs., 2 figs., 2 tabs

Estimating Marginal Returns to Education. NBER Working Paper No. 16474

Science.gov (United States)

Carneiro, Pedro; Heckman, James J.; Vytlacil, Edward J.

2010-01-01

This paper estimates the marginal returns to college for individuals induced to enroll in college by different marginal policy changes. The recent instrumental variables literature seeks to estimate this parameter, but in general it does so only under strong assumptions that are tested and found wanting. We show how to utilize economic theory and…

Correlation between margin fit and microleakage in complete crowns cemented with three luting agents

Directory of Open Access Journals (Sweden)

Paulo Henrique Orlato Rossetti

2008-02-01

Full Text Available Microleakage can be related to margin misfit. Also, traditional microleakage techniques are time-consuming. This study evaluated the existence of correlation between in vitro margin fit and a new microleakage technique for complete crowns cemented with 3 different luting agents. Thirty human premolars were prepared for full-coverage crowns with a convergence angle of 6 degrees, chamfer margin of 1.2 mm circumferentially, and occlusal reduction of 1.5 mm. Ni-Cr cast crowns were cemented with either zinc phosphate (ZP (S.S. White, resin-modified glass-ionomer (RMGI (Rely X Luting Cement or a resin-based luting agent (RC (Enforce. Margin fit (seating discrepancy and margin gap was evaluated according to criteria in the literature under microscope with 0.001 mm accuracy. After thermal cycling, crowns were longitudinally sectioned and microleakage scores at tooth-cement interface were obtained and recorded at ×100 magnification. Margin fit parameters were compared with the one-way ANOVA test and microleakage scores with Kruskal-Wallis and Dunn's tests (alpha=0.05. Correlation between margin fit and microleakage was analyzed with the Spearman's test (alpha=0.05. Seating discrepancy and marginal gap values ranged from 81.82 µm to 137.22 µm (p=0.117, and from 75.42 µm to 78.49 µm (p=0.940, respectively. Marginal microleakage scores were ZP=3.02, RMGI=0.35 and RC=0.12 (p0.05. Conclusion: Margin fit parameters and microleakage showed no strong correlations; cast crowns cemented with RMGI and RC had lower microleakage scores than ZP cement.

Glacitectonic deformation around the retreating margin of the last Irish ice sheet

Science.gov (United States)

Knight, J.

2008-12-01

Evidence for ice-marginal glacitectonic shunting and deformation of bedrock slabs is described from three sites around the west coast of Ireland. These sites (Brandon Bay, County Kerry; Pigeon Point, County Mayo; Inishcrone, County Sligo) are all locations where the late Devensian ice margin retreated on land and was confined to within limestone bedrock embayments. At these sites, flat-lying bedrock slabs (bedrock slabs have been variously stacked, rotated, deformed into open folds, and brecciated. Separating the bedrock slabs is either a thin layer (bedrock that shows internal folding; or a thicker (bedrock fractures and bedding planes and away from the ice margin, and that bedrock slabs were moved in part by hydraulic lift as well as thrust-style ice-marginal tectonics. The presence of a mosaic of warm and frozen ice-bed patches, in combination with strong geologic control and meltwater generation from behind the ice margin, can help explain formation of these unusual bedrock slab features.

New examples of marginally trapped surfaces and tubes in warped spacetimes

International Nuclear Information System (INIS)

Flores, J L; Haesen, S; Ortega, M

2010-01-01

In this paper we provide new examples of marginally trapped surfaces and tubes in FLRW spacetimes by using a basic relation between these objects and CMC surfaces in 3-manifolds. We also provide a new method to construct marginally trapped surfaces in closed FLRW spacetimes, which is based on the classical Hopf map. The utility of this method is illustrated by providing marginally trapped surfaces crossing the expanding and collapsing regions of a closed FLRW spacetime. The approach introduced in this paper is also extended to twisted spaces.

Denying Foreign Bank Entry: Implications For Bank Interest Margins

OpenAIRE

Ross Levine

2003-01-01

This paper examines the impact of restricting foreign bank entry on bank net interest margins while controlling for (a) impediments to domestic bank entry, (b) the degree of foreign bank ownership of the domestic banking industry, (c) an array of bank-specific characteristics, (c) banking sectorconcentration, and (d) various country traits. Using data on almost 1200 banks across 47 countries, the results suggest that restricting foreign bank entry boosts bank net interest margins. Also, restr...

Splenic marginal zone lymphoma: comprehensive analysis of gene expression and miRNA profiling.

Science.gov (United States)

Arribas, Alberto J; Gómez-Abad, Cristina; Sánchez-Beato, Margarita; Martinez, Nerea; Dilisio, Lorena; Casado, Felipe; Cruz, Miguel A; Algara, Patrocinio; Piris, Miguel A; Mollejo, Manuela

2013-07-01

Splenic marginal zone lymphoma is a small B-cell neoplasm whose molecular pathogenesis is still essentially unknown and whose differentiation from other small B-cell lymphomas is hampered by the lack of specific markers. We have analyzed the gene expression and miRNA profiles of 31 splenic marginal zone lymphoma cases. For comparison, 7 spleens with reactive lymphoid hyperplasia, 10 spleens infiltrated by chronic lymphocytic leukemia, 12 spleens with follicular lymphoma, 6 spleens infiltrated by mantle cell lymphoma and 15 lymph nodes infiltrated by nodal marginal zone lymphoma were included. The results were validated by qRT-PCR in an independent series including 77 paraffin-embedded splenic marginal zone lymphomas. The splenic marginal zone lymphoma miRNA signature had deregulated expression of 51 miRNAs. The most highly overexpressed miRNAs were miR-155, miR-21, miR-34a, miR-193b and miR-100, while the most repressed miRNAs were miR-377, miR-27b, miR-145, miR-376a and miR-424. MiRNAs located in 14q32-31 were underexpressed in splenic marginal zone lymphoma compared with reactive lymphoid tissues and other B-cell lymphomas. Finally, the gene expression data were integrated with the miRNA profile to identify functional relationships between genes and deregulated miRNAs. Our study reveals miRNAs that are deregulated in splenic marginal zone lymphoma and identifies new candidate diagnostic molecules for splenic marginal zone lymphoma.

Carfilzomib With or Without Rituximab in the Treatment of Waldenstrom Macroglobulinemia or Marginal Zone Lymphoma

Science.gov (United States)

2018-02-05

Marginal Zone Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Waldenstrom Macroglobulinemia; Refractory Marginal Zone Lymphoma; Refractory Waldenstrom Macroglobulinemia; Waldenstrom Macroglobulinemia

Wavelet Filtering to Reduce Conservatism in Aeroservoelastic Robust Stability Margins

Science.gov (United States)

Brenner, Marty; Lind, Rick

1998-01-01

Wavelet analysis for filtering and system identification was used to improve the estimation of aeroservoelastic stability margins. The conservatism of the robust stability margins was reduced with parametric and nonparametric time-frequency analysis of flight data in the model validation process. Nonparametric wavelet processing of data was used to reduce the effects of external desirableness and unmodeled dynamics. Parametric estimates of modal stability were also extracted using the wavelet transform. Computation of robust stability margins for stability boundary prediction depends on uncertainty descriptions derived from the data for model validation. F-18 high Alpha Research Vehicle aeroservoelastic flight test data demonstrated improved robust stability prediction by extension of the stability boundary beyond the flight regime.

Measure of departure from marginal point-symmetry for two-way contingency tables

Directory of Open Access Journals (Sweden)

Kouji Yamamoto

2013-05-01

Full Text Available For two-way contingency tables, Tomizawa (1985 considered the point-symmetry and marginal point-symmetry models, and Tomizawa, Yamamoto and Tahata (2007 proposed a measure to represent the degree of departure from point-symmetry. The present paper proposes a measure to represent the degree of departure from marginal pointsymmetry for two-way tables. The proposed measure is expressed by using Cressie-Read power-divergence or Patil-Taillie diversity index. This measure would be useful for comparing the degrees of departure from marginal point-symmetry in several tables. The relationship between the degree of departure from marginal point-symmetry and the measure is shown when it is reasonable to assume underlying bivariate normal distribution. Examples are shown.

Geophysical constraints on geodynamic processes at convergent margins: A global perspective

Science.gov (United States)

Artemieva, Irina; Thybo, Hans; Shulgin, Alexey

2016-04-01

Convergent margins, being the boundaries between colliding lithospheric plates, form the most disastrous areas in the world due to intensive, strong seismicity and volcanism. We review global geophysical data in order to illustrate the effects of the plate tectonic processes at convergent margins on the crustal and upper mantle structure, seismicity, and geometry of subducting slab. We present global maps of free-air and Bouguer gravity anomalies, heat flow, seismicity, seismic Vs anomalies in the upper mantle, and plate convergence rate, as well as 20 profiles across different convergent margins. A global analysis of these data for three types of convergent margins, formed by ocean-ocean, ocean-continent, and continent-continent collisions, allows us to recognize the following patterns. (1) Plate convergence rate depends on the type of convergent margins and it is significantly larger when, at least, one of the plates is oceanic. However, the oldest oceanic plate in the Pacific ocean has the smallest convergence rate. (2) The presence of an oceanic plate is, in general, required for generation of high-magnitude (M N 8.0) earthquakes and for generating intermediate and deep seismicity along the convergent margins. When oceanic slabs subduct beneath a continent, a gap in the seismogenic zone exists at depths between ca. 250 km and 500 km. Given that the seismogenic zone terminates at ca. 200 km depth in case of continent-continent collision, we propose oceanic origin of subducting slabs beneath the Zagros, the Pamir, and the Vrancea zone. (3) Dip angle of the subducting slab in continent-ocean collision does not correlate neither with the age of subducting oceanic slab, nor with the convergence rate. For ocean-ocean subduction, clear trends are recognized: steeply dipping slabs are characteristic of young subducting plates and of oceanic plates with high convergence rate, with slab rotation towards a near-vertical dip angle at depths below ca. 500 km at very high

Geochemical evidences of methane hydrate dissociation in Alaskan Beaufort Margin during Holocene

Science.gov (United States)

Uchida, M.; Rella, S.; Kubota, Y.; Kumata, H.; Mantoku, K.; Nishino, S.; Itoh, M.

2017-12-01

Alaskan Beaufort margin bear large abundances of sub-sea and permafrost methane hydrate[Ruppel, 2016]. During the Last Glacial, previous reported direct and indirect evidences accumulated from geochemical data from marginal sea sediment suggests that methane episodically released from hydrate trapped in the seafloor sediments[Kennett et al., 2000; Uchida et al., 2006, 2008; Cook et al, 2011]. Here we analyzed stable isotopes of foraminifera and molecular marker derived from the activity of methanotrophic bacteria from piston cores collected by the 2010 R/V Mirai cruise in Alaskan Beaufort Margin. Our data showed highly depleted 13C compositions of benthic foraminifera, suggesting indirect records of enhanced incorporation of 13C-depleted CO2 formed by methanotrophic process that use 12C-enriched methane as their main source of carbon. This is the first evidence of methane hydrate dissociation in Alaskan margin. Here we discussed timing of signals of methane dissociation with variability of sea ice and intermediate Atlantic water temperature. The dissociation of methane hydrate in the Alaskan Margin may be modulated by Atlantic warm intermediate water warming. Our results suggest that Arctic marginal regions bearing large amount methane hydrate may be a profound effect on future warming climate changes.

Marginal adaptation of newer root canal sealers to dentin: A SEM study.

Science.gov (United States)

Polineni, Swapnika; Bolla, Nagesh; Mandava, Pragna; Vemuri, Sayesh; Mallela, Madhusudana; Gandham, Vijaya Madhuri

2016-01-01

This in vitro study evaluated and compared the marginal adaptation of three newer root canal sealers to root dentin. Thirty freshly extracted human single-rooted teeth with completely formed apices were taken. Teeth were decoronated, and root canals were instrumented. The specimens were randomly divided into three groups (n = 10) based upon the sealer used. Group 1 - teeth were obturated with epoxy resin sealer (MM-Seal). Group 2 - teeth were obturated with mineral trioxide aggregate (MTA) based sealer (MTA Fillapex), Group 3 - teeth were obturated with bioceramic sealer (EndoSequence BC sealer). Later samples were vertically sectioned using hard tissue microtome and marginal adaptation of sealers to root dentin was evaluated under coronal and apical halves using scanning electron microscopy (SEM) and marginal gap values were recorded. The data were statistically analyzed by two-way ANOVA and Tukey's multiple post hoc test. The highest marginal gap was seen in Group 2 (apical-16680.00 nm, coronal-10796 nm) and the lowest marginal gap was observed in Group 1 (apical-599.42 nm, coronal-522.72 nm). Coronal halves showed superior adaptation compared to apical halves in all the groups under SEM. Within the limitations of this study epoxy resin-based MM-Seal showed good marginal adaptation than other materials tested.

The Effect of Sintering Time on the Marginal Fit of Zirconia Copings.

Science.gov (United States)

Khaledi, Amir Ali Reza; Vojdani, Mahroo; Farzin, Mitra; Pirouzi, Sudabeh; Orandi, Sepideh

2018-01-03

This study analyzed the effect of different sintering times on the marginal adaptation of zirconia ceramic copings. Thirty copings of pre-sintered 3Y-TZP blanks were milled and subsequently sintered in a special furnace for three different durations (n = 10 per group). The sintering time was 1 hour, 15 minutes for IPS e.max ZirCAD, 4 hours 20 minutes for Speed ZrO 2, and 7 hours 20 minutes for the conventional ZrO 2 group. The marginal gaps of specimens were measured at 18 spots on the master die by employing a digital microscope. One-way ANOVA test compared the mean differences among the 3 groups (α = 0.05). The mean values for the marginal gap of the IPS e.max ZirCAD, Speed ZrO 2 , and conventional ZrO 2 groups were 41.06 ± 14.03, 43.03 ± 11.67, and 39.88 ± 15.23 μm, respectively. There was no statistically significant difference among the groups regarding the marginal gap. Different sintering times did not alter the marginal fit of the zirconia copings. The mean values of the marginal gap were within the clinically acceptable level for all three groups. © 2018 by the American College of Prosthodontists.

Wintertime phytoplankton bloom in the Subarctic Pacific supported by continental margin iron

International Nuclear Information System (INIS)

Lam, Phoebe J.; Bishop, James K.B.; Henning, Cara C.; Marcus, Matthew A.; Waychunas, Glenn A.; Fung, Inez

2004-01-01

Heightened biological activity was observed in February 1996 in the high-nutrient low-chlorophyll (HNLC) subarctic North Pacific Ocean, a region that is thought to be iron-limited. Here we provide evidence supporting the hypothesis that Ocean Station Papa (OSP) in the subarctic Pacific received a lateral supply of particulate iron from the continental margin off the Aleutian Islands in the winter, coincident with the observed biological bloom. Synchrotron X-ray analysis was used to describe the physical form, chemistry, and depth distributions of iron in size fractionated particulate matter samples. The analysis reveals that discrete micron-sized iron-rich hotspots are ubiquitous in the upper 200m at OSP, more than 900km from the closest coast. The specifics of the chemistry and depth profiles of the Fe hot spots trace them to the continental margins. We thus hypothesize that iron hotspots are a marker for the delivery of iron from the continental margin. We confirm the delivery of continental margin iron to the open ocean using an ocean general circulation model with an iron-like tracer source at the continental margin. We suggest that iron from the continental margin stimulated a wintertime phytoplankton bloom, partially relieving the HNLC condition

An optimisation algorithm for determination of treatment margins around moving and deformable targets

International Nuclear Information System (INIS)

Redpath, Anthony Thomas; Muren, Ludvig Paul

2005-01-01

Purpose: Determining treatment margins for inter-fractional motion of moving and deformable clinical target volumes (CTVs) remains a major challenge. This paper describes and applies an optimisation algorithm designed to derive such margins. Material and methods: The algorithm works by expanding the CTV, as determined from a pre-treatment or planning scan, to enclose the CTV positions observed during treatment. CTV positions during treatment may be obtained using, for example, repeat CT scanning and/or repeat electronic portal imaging (EPI). The algorithm can be applied to both individual patients and to a set of patients. The margins derived will minimise the excess volume outside the envelope that encloses all observed CTV positions (the CTV envelope). Initially, margins are set such that the envelope is more than adequately covered when the planning CTV is expanded. The algorithm uses an iterative method where the margins are sampled randomly and are then either increased or decreased randomly. The algorithm is tested on a set of 19 bladder cancer patients that underwent weekly repeat CT scanning and EPI throughout their treatment course. Results: From repeated runs on individual patients, the algorithm produces margins within a range of ±2 mm that lie among the best results found with an exhaustive search approach, and that agree within 3 mm with margins determined by a manual approach on the same data. The algorithm could be used to determine margins to cover any specified geometrical uncertainty, and allows for the determination of reduced margins by relaxing the coverage criteria, for example disregarding extreme CTV positions, or an arbitrarily selected volume fraction of the CTV envelope, and/or patients with extreme geometrical uncertainties. Conclusion: An optimisation approach to margin determination is found to give reproducible results within the accuracy required. The major advantage with this algorithm is that it is completely empirical, and it is

Polyphase Rifting and Breakup of the Central Mozambique Margin

Science.gov (United States)

Senkans, Andrew; Leroy, Sylvie; d'Acremont, Elia; Castilla, Raymi

2017-04-01

The breakup of the Gondwana supercontinent resulted in the formation of the Central Mozambique passive margin as Africa and Antarctica were separated during the mid-Jurassic period. The identification of magnetic anomalies in the Mozambique Basin and Riiser Larsen Sea means that post-oceanisation plate kinematics are well-constrained. Unresolved questions remain, however, regarding the initial fit, continental breakup process, and the first relative movements of Africa and Antarctica. This study uses high quality multi-channel seismic reflection profiles in an effort to identify the major crustal domains in the Angoche and Beira regions of the Central Mozambique margin. This work is part of the integrated pluri-disciplinary PAMELA project*. Our results show that the Central Mozambique passive margin is characterised by intense but localised magmatic activity, evidenced by the existence of seaward dipping reflectors (SDR) in the Angoche region, as well as magmatic sills and volcanoclastic material which mark the Beira High. The Angoche region is defined by a faulted upper-continental crust, with the possible exhumation of lower crustal material forming an extended ocean-continent transition (OCT). The profiles studied across the Beira high reveal an offshore continental fragment, which is overlain by a pre-rift sedimentary unit likely to belong to the Karoo Group. Faulting of the crust and overlying sedimentary unit reveals that the Beira High has recorded several phases of deformation. The combination of our seismic interpretation with existing geophysical and geological results have allowed us to propose a breakup model which supports the idea that the Central Mozambique margin was affected by polyphase rifting. The analysis of both along-dip and along-strike profiles shows that the Beira High initially experienced extension in a direction approximately parallel to the Mozambique coastline onshore of the Beira High. Our results suggest that the Beira High results

Effect of different resin luting cements on the marginal fit of lithium disilicate pressed crowns.

Science.gov (United States)

Mounajjed, Radek; Salinas, Thomas J; Ingr, Tomas; Azar, Basel

2017-11-15

The vertical marginal discrepancy of restorations can increase upon cementation, and poor marginal fit can lead to cement dissolution, marginal discoloration, microleakage, and secondary caries. The amount of increase is related to the type of luting cement used, but how lithium disilicate pressed crowns are affected by different resin cements is unclear. The purpose of this in vitro study was to compare the effect of using different resin luting cements on the vertical marginal discrepancy of lithium disilicate pressed crowns. A total of 18 intact extracted mandibular third molars were disinfected in a solution of 10% formalin for 7 days and were then prepared to receive a ceramic crown. Impressions were made with polyvinyl siloxane and lithium disilicate pressed crowns made and cemented with 1 of 3 resin luting cements. The marginal discrepancy was measured at 4 points on the finishing line of each tooth, with optical microscopy at ×200 magnification before and after cementation. Statistical analysis was done with the Kruskal-Wallis test to compare the median marginal increase among the 3 groups. The least amount of marginal increase after cementation was with Harvard PremiumFlow cement, with an average marginal increase of 42 ±11 μm. RelyX Ultimate cement increased the margins by an average 45 ±29 μm. The highest marginal increase was found in the Enamel Plus HRi preheated composite resin group (116 ±47 μm). The marginal increase of pressed crowns cemented with preheated composite resin (Enamel Plus HRi) exceeded the clinically acceptable range of marginal discrepancy. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

A Directed Acyclic Graph-Large Margin Distribution Machine Model for Music Symbol Classification.

Science.gov (United States)

Wen, Cuihong; Zhang, Jing; Rebelo, Ana; Cheng, Fanyong

2016-01-01

Optical Music Recognition (OMR) has received increasing attention in recent years. In this paper, we propose a classifier based on a new method named Directed Acyclic Graph-Large margin Distribution Machine (DAG-LDM). The DAG-LDM is an improvement of the Large margin Distribution Machine (LDM), which is a binary classifier that optimizes the margin distribution by maximizing the margin mean and minimizing the margin variance simultaneously. We modify the LDM to the DAG-LDM to solve the multi-class music symbol classification problem. Tests are conducted on more than 10000 music symbol images, obtained from handwritten and printed images of music scores. The proposed method provides superior classification capability and achieves much higher classification accuracy than the state-of-the-art algorithms such as Support Vector Machines (SVMs) and Neural Networks (NNs).

17 CFR 31.18 - Margin calls.

Science.gov (United States)

2010-04-01

... transaction merchant is unable to effect personal contact with a leverage customer, a telegram sent to the....18 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION LEVERAGE TRANSACTIONS § 31.18 Margin calls. (a) No leverage transaction merchant shall liquidate a leverage contract because of...

Análisis de la calidad de servicio al cliente que se oferta en las agencias de registro civil de las ciudades de Riobamba, Ambato, Guaranda y Latacunga usando el modelo SERVQUAL.

OpenAIRE

Haro Sosa, Giovanny Lenin

2017-01-01

La investigación tiene por objetivo analizar la calidad de servicio al cliente que se oferta en las agencias de Registro Civil de las ciudades de Riobamba, Ambato, Guaranda y Latacunga usando el modelo SERVQUAL. Registro Civil ha implementado grandes cambios en los últimos años referente a infraestructura, innovación tecnológica y talento humano, sin embargo, de ello no existe un modelo de aseguramiento de la calidad del servicio, por lo cual se hace necesario visitar a cada un...

New Insights into Passive Margin Development from a Global Deep Seismic Reflection Dataset

Science.gov (United States)

Bellingham, Paul; Pindell, James; Graham, Rod; Horn, Brian

2014-05-01

The kinematic and dynamic evolution of the world's passive margins is still poorly understood. Yet the need to replace reserves, a high oil price and advances in drilling technology have pushed the international oil and gas industry to explore in the deep and ultra-deep waters of the continental margins. To support this exploration and help understand these margins, ION-GXT has acquired, processed and interpreted BasinSPAN surveys across many of the world's passive margins. Observations from these data lead us to consider the modes of subsidence and uplift at both volcanic and non-volcanic margins. At non-volcanic margins, it appears that frequently much of the subsidence post-dates major rifting and is not thermal in origin. Rather the subsidence is associated with extensional displacement on a major fault or shear zone running at least as deep as the continental Moho. We believe that the subsidence is structural and is probably associated with the pinching out (boudinage) of the Lower Crust so that the Upper crust effectively collapses onto the mantle. Eventually this will lead to the exhumation of the sub-continental mantle at the sea bed. Volcanic margins present more complex challenges both in terms of imaging and interpretation. The addition of volcanic and plutonic material into the system and dynamic effects all impact subsidence and uplift. However, we will show some fundamental observations regarding the kinematic development of volcanic margins and especially SDRs which demonstate that the process of collapse and the development of shear zones within and below the crust are also in existence at this type of margin. A model is presented of 'magma welds' whereby packages of SDRs collapse onto an emerging sub-crustal shear zone and it is this collapse which creates the commonly observed SDR geometry. Examples will be shown from East India, Newfoundland, Brazil, Argentina and the Gulf of Mexico.

Anisotropic Margin Expansions in 6 Anatomic Directions for Oropharyngeal Image Guided Radiation Therapy

International Nuclear Information System (INIS)

Yock, Adam D.; Garden, Adam S.; Court, Laurence E.; Beadle, Beth M.; Zhang, Lifei; Dong, Lei

2013-01-01

Purpose: The purpose of this work was to determine the expansions in 6 anatomic directions that produced optimal margins considering nonrigid setup errors and tissue deformation for patients receiving image-guided radiation therapy (IGRT) of the oropharynx. Methods and Materials: For 20 patients who had received IGRT to the head and neck, we deformably registered each patient's daily images acquired with a computed tomography (CT)-on-rails system to his or her planning CT. By use of the resulting vector fields, the positions of volume elements within the clinical target volume (CTV) (target voxels) or within a 1-cm shell surrounding the CTV (normal tissue voxels) on the planning CT were identified on each daily CT. We generated a total of 15,625 margins by dilating the CTV by 1, 2, 3, 4, or 5 mm in the posterior, anterior, lateral, medial, inferior, and superior directions. The optimal margins were those that minimized the relative volume of normal tissue voxels positioned within the margin while satisfying 1 of 4 geometric target coverage criteria and 1 of 3 population criteria. Results: Each pair of geometric target coverage and population criteria resulted in a unique, anisotropic, optimal margin. The optimal margin expansions ranged in magnitude from 1 to 5 mm depending on the anatomic direction of the expansion and on the geometric target coverage and population criteria. Typically, the expansions were largest in the medial direction, were smallest in the lateral direction, and increased with the demand of the criteria. The anisotropic margin resulting from the optimal set of expansions always included less normal tissue than did any isotropic margin that satisfied the same pair of criteria. Conclusions: We demonstrated the potential of anisotropic margins to reduce normal tissue exposure without compromising target coverage in IGRT to the head and neck

Geophysical constraints on geodynamical processes at convergent margins

DEFF Research Database (Denmark)

Artemieva, Irina; Thybo, Hans; Shulgin, Alexey

2016-01-01

Convergent margins, being the boundaries between colliding lithospheric plates, form the most disastrous areas in the world due to intensive, strong seismicity and volcanism. We review global geophysical data in order to illustrate the effects of the plate tectonic processes at convergent margins......, at least, one of the plates is oceanic. However, the oldest oceanic plate in the Pacific ocean has the smallest convergence rate. (2) The presence of an oceanic plate is, in general, required for generation of high-magnitude (M>8.0) earthquakes and for generating intermediate and deep seismicity along...... to shallow mantle levels....

Marginal Congestion Cost on a Dynamic Expressway Network

DEFF Research Database (Denmark)

Fosgerau, Mogens; Small, Kenneth A.

2012-01-01

a dynamic econometric model using unusually complete and accurate data from Danish motorways. We use the results to estimate the marginal external cost of adding a vehicle to a link's entry flow, finding it is highly influenced by the dynamic properties of the system of relationships between travel times......We formulate an empirical model of congestion for a series of sequential expressway links where queues may form and spill back. Its purpose is to disentangle the dynamic effect that a marginal vehicle has on the distribution of travel times experienced there and on connected links. We estimate...

An Evaluation of the Marginal Sharpness of the Porcelain Labial Margin Metal Ceramic Restoration

Science.gov (United States)

1991-05-01

these subgingival margins are open, significant bone resorption can result (Bjorn et al., 1969). Larato (1969a) examined 546 cast gold crowns and found...platinum foil was welded to the casting at three locations approximately 1.5 to 2 mm apart using an orthodontic spotwelder (Rocky Mountain Associates...individual stone dies with an autopolymerizing unfilled resin (Concise Orthodontic Bonding System, Dental Products/3M, St. Paul, MN). This Bis-GMA resin

Safety margin evaluation concepts for plant Up rates and life extension. Results of the OECD/NEA/CSNI working group on Safety Margin Action Plan (SMAP)

International Nuclear Information System (INIS)

Belac, J

2006-01-01

This presentation summarizes results of the OECD/NEA/CSNI working group on Safety Margin Action Plan (SMAP) aimed to develop generalized safety margin concept and means of its quantification for the process of evaluating plant safety in the frame of plant life extension and power up rating activities to be used by OECD member countries. (author)

Evaluation of marginal fit of two all-ceramic copings with two finish lines

Science.gov (United States)

Subasi, Gulce; Ozturk, Nilgun; Inan, Ozgur; Bozogullari, Nalan

2012-01-01

Objectives: This in-vitro study investigated the marginal fit of two all-ceramic copings with 2 finish line designs. Methods: Forty machined stainless steel molar die models with two different margin designs (chamfer and rounded shoulder) were prepared. A total of 40 standardized copings were fabricated and divided into 4 groups (n=10 for each finish line-coping material). Coping materials tested were IPS e.max Press and Zirkonzahn; luting agent was Variolink II. Marginal fit was evaluated after cementation with a stereomicroscope (Leica MZ16). Two-way analysis of variance and Tukey-HSD test were performed to assess the influence of each finish line design and ceramic type on the marginal fit of 2 all-ceramic copings (α =.05). Results: Two-way analysis of variance revealed no statistically significant differences for marginal fit relative to finish lines (P=.362) and ceramic types (P=.065). Conclusion: Within the limitations of this study, both types of all-ceramic copings demonstrated that the mean marginal fit was considered acceptable for clinical application (⩽120 μm). PMID:22509119

Veblen effect, marginal utility of money, and money illusion

OpenAIRE

Malakhov, Sergey

2013-01-01

The paper discovers microeconomic mechanism of Veblen effect as well as of Giffen case as results of the negative marginal utility of money. The marginal utility of consumption also becomes negative. The total consumption-leisure utility is increased due to the increase in leisure time. This overall effect results in the phenomenon of money illusion on the macroeconomic level. This general effect has deep historical and institutional grounds and, in order to minimize its disequilibrium econom...

Marginal versus Average Beta of Equity under Corporate Taxation

OpenAIRE

Lund, Diderik

2009-01-01

Even for fully equity-financed firms there may be substantial effects of taxation on the after-tax cost of capital. Among the few studies of these effects, even fewer identify all effects correctly. When marginal investment is taxed together with inframarginal, marginal beta differs from average if there are investment-related deductions like depreciation. To calculate asset betas, one should not only 'unlever observed equity betas, but 'untax' and 'unaverage' them. Risky tax claims are value...

Variability of the geothermal gradient across two differently aged magma-rich continental rifted margins of the Atlantic Ocean: the Southwest African and the Norwegian margins

Directory of Open Access Journals (Sweden)

E. Gholamrezaie

2018-02-01

Full Text Available The aim of this study is to investigate the shallow thermal field differences for two differently aged passive continental margins by analyzing regional variations in geothermal gradient and exploring the controlling factors for these variations. Hence, we analyzed two previously published 3-D conductive and lithospheric-scale thermal models of the Southwest African and the Norwegian passive margins. These 3-D models differentiate various sedimentary, crustal, and mantle units and integrate different geophysical data such as seismic observations and the gravity field. We extracted the temperature–depth distributions in 1 km intervals down to 6 km below the upper thermal boundary condition. The geothermal gradient was then calculated for these intervals between the upper thermal boundary condition and the respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal boundary condition. According to our results, the geothermal gradient decreases with increasing depth and shows varying lateral trends and values for these two different margins. We compare the 3-D geological structural models and the geothermal gradient variations for both thermal models and show how radiogenic heat production, sediment insulating effect, and thermal lithosphere–asthenosphere boundary (LAB depth influence the shallow thermal field pattern. The results indicate an ongoing process of oceanic mantle cooling at the young Norwegian margin compared with the old SW African passive margin that seems to be thermally equilibrated in the present day.

An IGRT margin concept for pelvic lymph nodes in high-risk prostate cancer

International Nuclear Information System (INIS)

Groher, M.; Kopp, P.; Deutschmann, H.; Sedlmayer, F.; Wolf, Frank; Drerup, M.

2017-01-01

Gold-marker-based image-guided radiation therapy (IGRT) of the prostate allows to correct for inter- and intrafraction motion and therefore to safely reduce margins for the prostate planning target volume (PTV). However, pelvic PTVs, when coadministered in a single plan (registered to gold markers [GM]), require reassessment of the margin concept since prostate movement is independent from the pelvic bony anatomy to which the lymphatics are usually referenced to. We have therefore revisited prostate translational movement relative to the bony anatomy to obtain adequate margins for the pelvic PTVs compensating mismatch resulting from referencing pelvic target volumes to GMs in the prostate. Prostate movement was analyzed in a set of 28 patients (25 fractions each, totaling in 684 fractions) and the required margins calculated for the pelvic PTVs according to Van Herk's margin formula M = 2.5 Σ + 1.64 (σ ' -σ p ). The overall mean prostate movement relative to bony anatomy was 0.9 ± 3.1, 0.6 ± 3.4, and 0.0 ± 0.7 mm in anterior/posterior (A/P), inferior/superior (I/S) and left/right (L/R) direction, respectively. Calculated margins to compensate for the resulting mismatch to bony anatomy were 9/9/2 mm in A/P, I/S, and L/R direction and 10/11/6 mm if an additional residual error of 2 mm was assumed. GM-based IGRT for pelvic PTVs is feasible if margins are adapted accordingly. Margins could be reduced further if systematic errors which are introduced during the planning CT were eliminated. (orig.) [de

PRE-RIFT COMPRESSIONAL STRUCTURES AS A CONTROL ON PASSIVE MARGIN FORMATION

DEFF Research Database (Denmark)

Schiffer, Christian; Petersen, Kenni Dinesen

Passive margins are commonly separated into volcanic and non-volcanic modes, each with a distinct formation mechanism and structure. Both form the transition from continental to oceanic crust. Large amounts of geophysical data at passive margins show that the tapering continental crust is often u...

Simulación y validación de modelos de destilación por lotes usando Aspen Batch Modeler: recuperación de epóxido de limoneno

OpenAIRE

Yeison Agudelo; Rolando Barrera Zapata

2016-01-01

Se desarrolló el modelado y simulación de una columna de destilación por lotes para la recuperación de epóxido de limoneno de una mezcla multicomponente, usando el software especializado Aspen Batch Modeler. Para la validación de los modelos se desarrolló el proceso experimental en un equipo de roto-evaporación, donde se varió la composición inicial de la mezcla, temperatura y presión de operación. La composición final de fondos y destilado se determinó a través de cromatografía de gases. Los...

Primary cutaneous marginal zone B-cell lymphoma: clinical and histological aspects.

Science.gov (United States)

Khaled, A; Sassi, S; Fazaa, B; Ben Hassouna, J; Ben Romdhane, K; Kamoun, M R

2009-02-01

According to the WHO-EORTC classification of cutaneous lymphomas, primary cutaneous marginal zone B-cell lymphoma are now well characterized. We report here a case of primary cutaneous marginal zone B-cell lymphoma in a 51 year-old man in which the diagnosis was made using both histology and immunopathology. The patient had no remarkable medical history, no history of either acute inflammation or insect bite, and presented with a 5 cm solitary asymptomatic erythematous firm, multinodular and infiltrated plaque on the back for 12 months. Histological examination and immunohistochemical study of a cutaneous biopsy provided a differential diagnosis between B cell lymphoma and lymphocytoma cutis. Full body work up revealed no signs of extracutaneous dissemination. The patient underwent surgical excision of the nodule. Histological examination showed a histological and immunophenotyping profile typical of primary cutaneous marginal zone B-cell lymphoma. The lesion was completely excised with clear margins and no recurrence occurred after a 12 month-follow-up period. Primary cutaneous marginal zone B-cell lymphoma are low-grade lymphomas that have an indolent course and a high tendency to recur. They should be differentiated from lymphocytoma cutis and from the other types of cutaneous B cell lymphomas that have a different course and prognosis.

Operational margin monitoring system for boiling water reactor power plants

International Nuclear Information System (INIS)

Fukutomi, S.; Takigawa, Y.

1992-01-01

This paper reports on an on-line operational margin monitoring system which has been developed for boiling water reactor power plants to improve safety, reliability, and quality of reactor operation. The system consists of a steady-state core status prediction module, a transient analysis module, a stability analysis module, and an evaluation and guidance module. This system quantitatively evaluates the thermal margin during abnormal transients as well as the stability margin, which cannot be evaluated by direct monitoring of the plant parameters, either for the current operational state or for a predicted operating state that may be brought about by the intended operation. This system also gives operator guidance as to appropriate or alternate operations when the operating state has or will become marginless

Deformation patterns and seismic hazard along the eastern Sunda margin

Science.gov (United States)

Kopp, Heidrun; Djajadihardja, Yusuf; Flueh, Ernst R.; Hindle, David; Klaeschen, Dirk; Mueller, Christian; Planert, Lars; Reichert, Christian; Shulgin, Alexey; Wittwer, Andreas

2010-05-01

The eastern Sunda margin offshore Java, Bali, Lombok and Sumba is the site of oceanic subduction of the Indo-Australian plate underneath the Indonesian archipelago. Data from a suite of geophysical experiments conducted between 1997-2006 using RV SONNE as platform include seismic and seismological studies, potential field measurements and high-resolution seafloor bathymetry mapping. Tomographic inversions provide an image of the ongoing deformation of the forearc and the deep subsurface. We investigate the role of various key mechanisms that shape the first-order features characterizing the present margin architecture. Our contribution evaluates the differences in architecture and evolution along the Java forearc from a marine perspective to better understand the variation in tectonic styles and segmentation of the convergent margin, including its seismic risk potential.

JMat - Herramienta remota de cálculo y multiusuario para el aprendizaje basado en problemas usando Matlab

Directory of Open Access Journals (Sweden)

Bladimir Bacca Cortes

2011-01-01

Full Text Available JMat es una herramienta de cálculo basada en JAVA y EJS (Easy Java Simulations, con un esquema cliente / servidor, soporte multi-usuario y acceso remoto a Matlab. La aplicación está orientada a brindar a los usuarios una interacción con Matlab usando tres interfaces: Consola de Comandos, donde se invocan remotamente comandos de texto compatibles con Matlab. Espacio de Trabajo y Graficación, donde se mantiene un registro automático de las variables de usuario y se grafican individualmente. Funciones de usuario y Transferencia de Archivos, donde el usuario crea sus funciones, envía y recibe datos hacia y desde el servidor. JMat requiere un acceso a Internet, un servidor remoto donde esté instalado Matlab y un cliente (Navegador WEB o aplicación. No se requiere Matlab en el cliente. JMat está siendo usada actualmente en la Universidad del Valle en los cursos de Control Automático de Procesos, Control Inteligente, Redes Neuronales Artificiales, Procesamiento de Señales y Tratamiento Digital de Imágenes como herramienta para el aprendizaje basado en problemas empleando la plataforma de eLearning de la Universidad del Valle.

Application of fermionic marginal constraints to hybrid quantum algorithms

Science.gov (United States)

Rubin, Nicholas C.; Babbush, Ryan; McClean, Jarrod

2018-05-01

Many quantum algorithms, including recently proposed hybrid classical/quantum algorithms, make use of restricted tomography of the quantum state that measures the reduced density matrices, or marginals, of the full state. The most straightforward approach to this algorithmic step estimates each component of the marginal independently without making use of the algebraic and geometric structure of the marginals. Within the field of quantum chemistry, this structure is termed the fermionic n-representability conditions, and is supported by a vast amount of literature on both theoretical and practical results related to their approximations. In this work, we introduce these conditions in the language of quantum computation, and utilize them to develop several techniques to accelerate and improve practical applications for quantum chemistry on quantum computers. As a general result, we demonstrate how these marginals concentrate to diagonal quantities when measured on random quantum states. We also show that one can use fermionic n-representability conditions to reduce the total number of measurements required by more than an order of magnitude for medium sized systems in chemistry. As a practical demonstration, we simulate an efficient restoration of the physicality of energy curves for the dilation of a four qubit diatomic hydrogen system in the presence of three distinct one qubit error channels, providing evidence these techniques are useful for pre-fault tolerant quantum chemistry experiments.

Pricing hospital care: Global budgets and marginal pricing strategies.

Science.gov (United States)

Sutherland, Jason M

2015-08-01

The Canadian province of British Columbia (BC) is adding financial incentives to increase the volume of surgeries provided by hospitals using a marginal pricing approach. The objective of this study is to calculate marginal costs of surgeries based on assumptions regarding hospitals' availability of labor and equipment. This study is based on observational clinical, administrative and financial data generated by hospitals. Hospital inpatient and outpatient discharge summaries from the province are linked with detailed activity-based costing information, stratified by assigned case mix categorizations. To reflect a range of operating constraints governing hospitals' ability to increase their volume of surgeries, a number of scenarios are proposed. Under these scenarios, estimated marginal costs are calculated and compared to prices being offered as incentives to hospitals. Existing data can be used to support alternative strategies for pricing hospital care. Prices for inpatient surgeries do not generate positive margins under a range of operating scenarios. Hip and knee surgeries generate surpluses for hospitals even under the most costly labor conditions and are expected to generate additional volume. In health systems that wish to fine-tune financial incentives, setting prices that create incentives for additional volume should reflect knowledge of hospitals' underlying cost structures. Possible implications of mis-pricing include no response to the incentives or uneven increases in supply. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Perlindungan Hukum Dalam Transaksi Margin Trading Dan Short Sales Di Pasar Modal

OpenAIRE

Kiandi, Ferry

2015-01-01

In the world of capital markets, there are many facilities offered by the securities, among other things, are margin trading and short selling. Margin trading is one of the facilities provided by the brokerage firm to investors. In margin trading, securuties (effects) purchase transactions made by the customers are financed by securities companies. So the investor can make the transaction exceeding the amount of money he has. In this facility, investors do not have to return th...

Read margin analysis of crossbar arrays using the cell-variability-aware simulation method

Science.gov (United States)

Sun, Wookyung; Choi, Sujin; Shin, Hyungsoon

2018-02-01

This paper proposes a new concept of read margin analysis of crossbar arrays using cell-variability-aware simulation. The size of the crossbar array should be considered to predict the read margin characteristic of the crossbar array because the read margin depends on the number of word lines and bit lines. However, an excessively high-CPU time is required to simulate large arrays using a commercial circuit simulator. A variability-aware MATLAB simulator that considers independent variability sources is developed to analyze the characteristics of the read margin according to the array size. The developed MATLAB simulator provides an effective method for reducing the simulation time while maintaining the accuracy of the read margin estimation in the crossbar array. The simulation is also highly efficient in analyzing the characteristic of the crossbar memory array considering the statistical variations in the cell characteristics.

A Directed Acyclic Graph-Large Margin Distribution Machine Model for Music Symbol Classification.

Directory of Open Access Journals (Sweden)

Cuihong Wen

Full Text Available Optical Music Recognition (OMR has received increasing attention in recent years. In this paper, we propose a classifier based on a new method named Directed Acyclic Graph-Large margin Distribution Machine (DAG-LDM. The DAG-LDM is an improvement of the Large margin Distribution Machine (LDM, which is a binary classifier that optimizes the margin distribution by maximizing the margin mean and minimizing the margin variance simultaneously. We modify the LDM to the DAG-LDM to solve the multi-class music symbol classification problem. Tests are conducted on more than 10000 music symbol images, obtained from handwritten and printed images of music scores. The proposed method provides superior classification capability and achieves much higher classification accuracy than the state-of-the-art algorithms such as Support Vector Machines (SVMs and Neural Networks (NNs.

The rifted margin of Saudi Arabia

Science.gov (United States)

McClain, J. S.; Orcutt, J. A.

The structure of rifted continental margins has always been of great scientific interest, and now, with dwindling economic oil deposits, these complex geological features assume practical importance as well. The ocean-continent transition is, by definition, laterally heterogeneous and likely to be extremely complicated. The southernmost shotpoints (4, 5, and 6) in the U.S. Geological Survey seismic refraction profile in the Kingdom of Saudi Arabia lie within a transition region and thus provide a testing ground for methods that treat wave propagation in laterally heterogeneous media. This portion of the profile runs from the Farasan Islands in the Red Sea across the coast line and the Hijaz-Asir escarpment into the Hijaz-Asir tectonic province. Because the southernmost shotpoint is within the margin of the Saudi sub-continent, the full transition region is not sampled. Furthermore, such an experiment is precluded by the narrowness of the purely oceanic portion of the Red Sea.

Impact of Margin Status on Local Recurrence After Mastectomy for Ductal Carcinoma In Situ

International Nuclear Information System (INIS)

Childs, Stephanie K.; Chen, Yu-Hui; Duggan, Margaret M.; Golshan, Mehra; Pochebit, Stephen; Punglia, Rinaa S.; Wong, Julia S.; Bellon, Jennifer R.

2013-01-01

Purpose: To examine the rate of local recurrence according to the margin status for patients with pure ductal carcinoma in situ (DCIS) treated by mastectomy. Methods and Materials: One hundred forty-five consecutive women who underwent mastectomy with or without radiation therapy for DCIS from 1998 to 2005 were included in this retrospective analysis. Only patients with pure DCIS were eligible; patients with microinvasion were excluded. The primary endpoint was local recurrence, defined as recurrence on the chest wall; regional and distant recurrences were secondary endpoints. Outcomes were analyzed according to margin status (positive, close (≤2 mm), or negative), location of the closest margin (superficial, deep, or both), nuclear grade, necrosis, receptor status, type of mastectomy, and receipt of hormonal therapy. Results: The primary cohort consisted of 142 patients who did not receive postmastectomy radiation therapy (PMRT). For those patients, the median follow-up time was 7.6 years (range, 0.6-13.0 years). Twenty-one patients (15%) had a positive margin, and 23 patients (16%) had a close (≤2 mm) margin. The deep margin was close in 14 patients and positive in 6 patients. The superficial margin was close in 13 patients and positive in 19 patients. One patient experienced an isolated invasive chest wall recurrence, and 1 patient had simultaneous chest wall, regional nodal, and distant metastases. The crude rates of chest wall recurrence were 2/142 (1.4%) for all patients, 1/21 (4.8%) for those with positive margins, 1/23 (4.3%) for those with close margins, and 0/98 for patients with negative margins. PMRT was given as part of the initial treatment to 3 patients, 1 of whom had an isolated chest wall recurrence. Conclusions: Mastectomy for pure DCIS resulted in a low rate of local or distant recurrences. Even with positive or close mastectomy margins, the rates of chest wall recurrences were so low that PMRT is likely not warranted

Medium-term marginal costs in competitive generation power markets

International Nuclear Information System (INIS)

Reneses, J.; Centeno, E.; Barquin, J.

2004-01-01

The meaning and significance of medium-term marginal costs for a generation company in a competitive power market in analysed. A methodology to compute and decompose medium-term generation marginal costs in a competitive environment is proposed. The methodology is based on a market equilibrium model. The aim is to provide a useful tool for generation companies so that they can manage their resources in an optimal way, helping them with their operation, decision-making processes, asset valuations or contract assessments. (author)

Estimate potential evaporation and solar radiation in the Yaqui valley, Sonora, Mexico, using data from satellite; Estimacion de evaporacion y radiacion solar en el valle del Yaqui, Sonora, usando datos de satelite

Energy Technology Data Exchange (ETDEWEB)

J Watts, Christopher; Rodriguez, Julio Cesar [Instituto del Medio Ambiente y el Desarrollo sustentable del estado de Sonora (Mexico); Garatuza Payan, Jaime [Instituto Tecnologico de Sonora (Mexico); Henk de Bruin [Universidad Agricola de Wageningen (Netherlands); Stewart, John [Universidad de Southampton (United Kingdom)

1999-12-01

The data from tow automatic weather stations in the Yaqui valley were used to estimate potential evaporation using the Makkink formula, based on observed incoming solar radiation and climatological values of air temperature. The usefulness of this formula was assessed by comparison with the Penman-Monteith, Penman and Priestley-Taylor formula and measurements of net radiation. A methodology was presented for estimating incoming solar radiation using visible band data from the GOES satellite. Comparisons against ground-based measurements from two pyranometers installed in the Yaqui valley gave good results, particularly in months with low cloud cover. Images for August 1993 were used to produce a map of the spatial distribution of potential evaporation. [Spanish] Para calcular la evaporacion potencial en el valle del Yaqui, usando la formula de Makkink, se utilizaron datos de dos estaciones meteorologicas automaticas. La mencionada formula se basa en la radiacion solar incidente observada y en ciertos valores climatologicos de temperatura del aire. Se evaluo la utilidad de esta formula, comparandola con las de Penman-Monteith, Pennan y Priestley-Taylor, asi como con mediciones de radiacion neta. Se desarrollo una metodologia para estimar la radiacion solar incidente usando la banda visible del satelite GOES. Se hizo una comparacion con mediciones de dos piranometros instalados en el valla del Yaqui, obteniendose buenos resultados, principalmente en meses con poca nubosidad. Se utilizaron imagenes de agosto de 1993 para producir un mapa de la distribucion espacial de la evaporacion potencial.

Perceived marginalization and aggression: a longitudinal study with low-educated adolescents.

Science.gov (United States)

Issmer, Christian; Wagner, Ulrich

2015-03-01

Social exclusion can evoke aggression. In the past two decades research has demonstrated this effect both for interpersonal and societal forms of exclusion. In addition, recent violent uprisings, like the London riots in August 2011, have been linked to social exclusion in the media. However, so far there is a lack of longitudinal studies which examine the aggression-enhancing effect of societal-level exclusion (i.e., marginalization) in disadvantaged groups. This research investigates the impact of perceived marginalization on aggression in a sample of N = 181 adolescents with a low educational background by means of a two-wave longitudinal study. The results of structural equation analyses are consistent with the hypothesis that perceived marginalization enhances aggression, and that this effect is mediated by the extent of negative societal meta-stereotypes. Furthermore, the reverse path from aggression to perceptions of marginalization is also significant. We discuss the implications of these findings and highlight practical consequences. © 2014 The British Psychological Society.

Calculating radiotherapy margins based on Bayesian modelling of patient specific random errors

International Nuclear Information System (INIS)

Herschtal, A; Te Marvelde, L; Mengersen, K; Foroudi, F; Ball, D; Devereux, T; Pham, D; Greer, P B; Pichler, P; Eade, T; Kneebone, A; Bell, L; Caine, H; Hindson, B; Kron, T; Hosseinifard, Z

2015-01-01

Collected real-life clinical target volume (CTV) displacement data show that some patients undergoing external beam radiotherapy (EBRT) demonstrate significantly more fraction-to-fraction variability in their displacement (‘random error’) than others. This contrasts with the common assumption made by historical recipes for margin estimation for EBRT, that the random error is constant across patients. In this work we present statistical models of CTV displacements in which random errors are characterised by an inverse gamma (IG) distribution in order to assess the impact of random error variability on CTV-to-PTV margin widths, for eight real world patient cohorts from four institutions, and for different sites of malignancy. We considered a variety of clinical treatment requirements and penumbral widths. The eight cohorts consisted of a total of 874 patients and 27 391 treatment sessions. Compared to a traditional margin recipe that assumes constant random errors across patients, for a typical 4 mm penumbral width, the IG based margin model mandates that in order to satisfy the common clinical requirement that 90% of patients receive at least 95% of prescribed RT dose to the entire CTV, margins be increased by a median of 10% (range over the eight cohorts −19% to +35%). This substantially reduces the proportion of patients for whom margins are too small to satisfy clinical requirements. (paper)

MARGINALIZATION OF PARWA LEATHER PUPPET IN GIANYAR REGENCY IN GLOBALIZATION ERA

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I Made Yudabakti

2013-12-01

Full Text Available This present study discussed the marginalization of the Parwa Leather Puppet in Gianyar Regency in the globalization era. It discussed the form, the causing factors, and the impact of marginalization. The qualitative interpretative method was used to analyze the problems of the study. The data were collected using the techniques of observation, in-depth interview, documentary study, and library research. The data were qualitatively analyzed. The results of the study showed that there were several forms of marginalization occurring to the Parwa Leather Puppet ‘Wayang Kulit Parwa’ (WKP in Gianyar Regency. This was indicated by the change in the context of performance and indication of marginalization. The forms of the context of performance were made up of the facts that (a the viewers shifted from the young generation to the old generation; (b it used to be performed as an offering but now it was performed as a commodity or comodification; (c technology played more important roles (the lighting, sound system, and the material for making the puppet, and d the accompanying gamelan orchestra changed. Marginalization was indicated by (a the fall in the frequency of performance, (b WKP was getting less popular in the community; (c fewer people were getting interested in WKP performance; and (e WKP was getting less respected. The factors responsible for the marginalization of WKP in Gianyar Regency were the facts that less people were interested in WKP, the decrease in the WKP puppeteer’s activities, the policy issued by the traditional institution was weak, and the supervision made by the local government of Gianyar was weak. In addition, WKP was less prospective; the current community needed more amusement than guidance, the rise in the impact of foreign cultural art, more and more sources of modern amusements were made available, and the impact of telecommunication technology. The marginalization of WKP in Gianyar Regency led to impacts and

Orogenic structural inheritance and rifted passive margin formation

Science.gov (United States)

Salazar Mora, Claudio A.; Huismans, Ritske S.

2016-04-01

Structural inheritance is related to mechanical weaknesses in the lithosphere due to previous tectonic events, e.g. rifting, subduction and collision. The North and South Atlantic rifted passive margins that formed during the breakup of Western Gondwana, are parallel to the older Caledonide and the Brasiliano-Pan-African orogenic belts. In the South Atlantic, 'old' mantle lithospheric fabric resulting from crystallographic preferred orientation of olivine is suggested to play a role during rifted margin formation (Tommasi and Vauchez, 2001). Magnetometric and gravimetric mapping of onshore structures in the Camamu and Almada basins suggest that extensional faults are controlled by two different directions of inherited older Brasiliano structures in the upper lithosphere (Ferreira et al., 2009). In the South Atlantic Campos Basin, 3D seismic data indicate that inherited basement structures provide a first order control on basin structure (Fetter, 2009). Here we investigate the role of structural inheritance on the formation of rifted passive margins with high-resolution 2D thermo-mechanical numerical experiments. The numerical domain is 1200 km long and 600 km deep and represents the lithosphere and the sublithospheric mantle. Model experiments were carried out by creating self-consistent orogenic inheritance where a first phase of orogen formation is followed by extension. We focus in particular on the role of varying amount of orogenic shortening, crustal rheology, contrasting styles of orogen formation on rifted margin style, and the time delay between orogeny and subsequent rifted passive formation. Model results are compared to contrasting structural styles of rifted passive margin formation as observed in the South Atlantic. Ferreira, T.S., Caixeta, J.M., Lima, F.D., 2009. Basement control in Camamu and Almada rift basins. Boletim de Geociências da Petrobrás 17, 69-88. Fetter, M., 2009. The role of basement tectonic reactivation on the structural evolution

Origins of saline fluids at convergent margins

Science.gov (United States)

Martin, Jonathan B.; Kastner, Miriam; Egeberg, Per Kr.

The compositions of pore and venting fluids at convergent margins differ from seawater values, reflecting mixing and diagenesis. Most significantly, the concentration of Cl-, assumed to be a conservative ion, differs from its seawater value. Chloride concentrations could be elevated by four processes, although two, the formation of gas hydrate and ion filtration by clay membranes, are insignificant in forming saline fluids at convergent margins. During the formation of gas hydrate, the resulting Cl--rich fluids, estimated to contain an average excess of ˜140 mM Cl- over seawater value, probably would be flushed from the sediment when the pore fluids vent to seawater. Ion filtration by clay membranes requires compaction pressures typical of >2 km burial depths. Even at these depths, the efficiency of ion filtration will be negligible because (1) fluids will flow through fractures, thereby bypassing clay membranes, (2) concentrations of clay minerals are diluted by other phases, and (3) during burial, smectite converts to illite, which has little capacity for ion filtration. A third process, mixing with subaerially evaporated seawater, elevates Cl- concentrations to 1043 mM in forearc basins along the Peru margin. Evaporation of seawater, however, will be important only in limited geographic regions that are characterized by enclosed basins, arid climates, and permeable sediments. At the New Hebrides and Izu-Bonin margins, Cl- concentrations are elevated to a maximum of 1241 mM. The process responsible for this increase is the alteration of volcanic ash to hydrous clay and zeolite minerals. Mass balance calculations, based on the decrease in δ18O values to -9.5‰ (SMOW), suggest that the Cl- concentrations could increase solely from the formation of smectite in a closed system. The diagenesis of volcanic ash also alters the concentrations of most dissolved species in addition to Cl-. Depending on the volume of this altered fluid, it could influence seawater

Impact of Close and Positive Margins in Transoral Laser Microsurgery for Tis–T2 Glottic Cancer

Directory of Open Access Journals (Sweden)

Ivana Fiz

2017-10-01

Full Text Available IntroductionTransoral laser microsurgery (TLM represents one of the most effective treatment strategies for Tis–T2 glottic squamous cell carcinomas (SCC. The prognostic influence of close/positive margins is still debated, and the role of narrow band imaging (NBI in their intraoperative definition is still to be validated on large cohort of patients. This study analyzed the influence of margin status on recurrence-free survival (RFS and disease-specific survival (DSS.MethodsWe retrospectively studied 507 cases of pTis–T1b (Group A and 127 cases of pT2 (Group B glottic SCC. We identified the following margin status: negative (n = 232, close superficial (n = 79, close deep (CD (n = 35, positive single superficial (n = 146, positive multiple superficial (n = 94, and positive deep (n = 48 and analyzed their impact on RFS and DSS. Close margins were defined by tumor-margin distance <1 mm. Pre-TLM margins were defined by white light in 323 patients, whereas NBI was employed in 311 patients.ResultsIn Group A, DSS and RFS were reduced in positive multiple superficial and positive deep margins (DSS = 96.1 and 97%, both p < 0.05; RFS = 72%, p < 0.001 and 75.8%, p < 0.01. In Group B, DSS was reduced in positive multiple superficial margins (82.4%, p < 0.05. RFS was reduced in positive single superficial, positive multiple superficial, and positive deep margins (62.5, 41.2, and 53.3%, p < 0.01. In the entire population, RFS was reduced in CD margins (77.1%, p < 0.05. Use of NBI led to improvement in RFS and DSS.ConclusionThe study indicates that close and positive single superficial margins do not affect DSS. By contrast, all types of margin positivity predict the occurrence of relapses, albeit with different likelihood, depending on stage/margin type. CD margins should be considered as a single risk factor. Use of NBI granted better intraoperative margins definition.

Magmatic development of the outer Vøring Margin

Science.gov (United States)

Breivik, Asbjorn; Faleide, Jan Inge; Mjelde, Rolf; Flueh, Ernst; Murai, Yoshio

2013-04-01

The Vøring Plateau off mid-Norway is a volcanic passive margin, located north of the East Jan Mayen Fracture Zone (EJMFZ). Large volumes of magmatic rocks were emplaced during Early Eocene margin formation. In 2003, an ocean bottom seismometer survey was acquired on the Vøring and Lofoten margins. One profile crosses from the Vøring Plateau to the Vøring Spur, an oceanic plateau north of the EJMFZ. The P-wave data were modeled by ray-tracing in a 2D velocity model of the crust. The process behind the excess magmatism can be estimated by comparing seismic velocity (VP) with igneous thickness (H). This profile and two other profiles farther north show a positive H-VP correlation, consistent with a hot mantle reservoir of finite extent under the margin at breakup. However, during the first two million years, magma production appears to be augmented by a secondary process. By 51-51.5 Ma melting may be caused by elevated mantle temperature alone. Seismic stratigraphy around the Vøring Spur shows at least two inversion events, with the main episode tentatively in the Upper Miocene, apparently through igneous growth to create the up to 15 km crustal thickness. The H-VP correlation of the spur is low, indicating constant and moderate-degree mantle melting not tied to the breakup magmatism. The admittance function between bathymetry and free-air gravity shows that the high is near local isostatic equilibrium, discounting that compressional flexure at the EJMFZ shaped the high. We also find no evidence for the proposed Early Eocene triple junction in the area.

Improved statistical confirmation of margins for setpoints and transients

International Nuclear Information System (INIS)

Nutt, W.T.

2001-01-01

Framatome ANP Richland, Inc. has developed an integrated, automated, statistical methodology for Pressurized Water Reactors (PWRs). Margins for transients and calculated trips are confirmed using several new applications of probability theory. The methods used for combining statistics reduces the conservatisms inherent in conventional methods and avoids the numerical limitations and time constraints imposed by Monte Carlo techniques. The new methodology represents the state of the art in the treatment of uncertainties for reactor protection systems. It all but eliminates concerns with the calculated trips for PWRs and by improving the margin for all transients will allow for far more aggressive peaking limits and fuel management schemes. The automated nature of the bulk of this process saves Framatome ANP time and effort, minimizes the potential for errors and makes the analysis for all cycles and plants consistent. The enhanced margins remove analytical limitations from the customer and allow for more economical operation of the plant. (authors)

Molecular pathogenesis of splenic and nodal marginal zone lymphoma.

Science.gov (United States)

Spina, Valeria; Rossi, Davide

Genomic studies have improved our understanding of the biological basis of splenic (SMZL) and nodal (NMZL) marginal zone lymphoma by providing a comprehensive and unbiased view of the genes/pathways that are deregulated in these diseases. Consistent with the physiological involvement of NOTCH, NF-κB, B-cell receptor and toll-like receptor signaling in mature B-cells differentiation into the marginal zone B-cells, many oncogenic mutations of genes involved in these pathways have been identified in SMZL and NMZL. Beside genetic lesions, also epigenetic and post-transcriptional modifications contribute to the deregulation of marginal zone B-cell differentiation pathways in SMZL and NMZL. This review describes the progress in understanding the molecular mechanism underlying SMZL and NMZL, including molecular and post-transcriptional modifications, and discusses how information gained from these efforts has provided new insights on potential targets of diagnostic, prognostic and therapeutic relevance in SMZL and NMZL. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Lead poisoning and marginalization in newborns of Morelos, Mexico].

Science.gov (United States)

Téllez-Rojo, Martha María; Bautista-Arredondo, Luis F; Richardson, Vesta; Estrada-Sánchez, Daniel; Ávila-Jiménez, Laura; Ríos, Camilo; Cantoral-Preciado, Alejandra; Romero-Martínez, Martín; Flores-Pimentel, Delia; Melo-Zurita, María Del Carmen; Romero-Ramírez, Anita; León-Mazón, Marco Antonio; Montes, Sergio; Fuller, Richard; Hernández-Ávila, Mauricio

2017-01-01

To determine the prevalence of lead (Pb) poisoning at birth in Morelos, analyze its distribution by social marginalization level, and estimate the association with the use of lead glazed ceramics (LGC). Blood lead level (BLL) in umbilical cord was measured in a representative sample of 300 randomly selected births at the Morelos Health Services and state IMSS. The prevalence of Pb poisoning at birth (BLL> 5μg/dL) was 14.7% (95%CI: 11.1, 19.3) and 22.2% (95%CI: 14.4, 32.5) in the most socially marginalized municipalities. 57.1% (95%CI: 51.3, 62.7) of the mothers used LGC during pregnancy, and the frequency of use was significantly associated with BLL. This is the first study to document the proportion of newborns with Pb poisoning who are at risk of experiencing the related adverse effects. It is recommended to monitor BLL at birth and take action to reduce this exposure, especially in socially marginalized populations.

Desenvolvimento e validação de metodos para a determinação de antimicrobianos em leite e farmacos usando a cromatografia liquida de alta eficiencia e eletroforese capilar

OpenAIRE

Monica Cecilia Vargas Mamani

2007-01-01

Resumo: Antimicrobianos são largamente empregados na medicina veterinária e resíduos destes podem permanecer nos alimentos de origem animal, acima de valores considerados seguros, quando não são respeitadas as boas práticas veterinárias. O objetivo deste trabalho foi o desenvolvimento e validação de métodos para a determinação de tetraciclinas, sulfonamidas, cloranfenicol e fluoroquinolonas em fármacos usando a eletroforese capilar (CE), assim como método multiresíduos para a determinação de ...

Accountable Accounting: Carbon-Based Management on Marginal Lands

Directory of Open Access Journals (Sweden)

Tara L. DiRocco

2014-04-01

Full Text Available Substantial discussion exists concerning the best land use options for mitigating greenhouse gas (GHG emissions on marginal land. Emissions-mitigating land use options include displacement of fossil fuels via biofuel production and afforestation. Comparing C recovery dynamics under these different options is crucial to assessing the efficacy of offset programs. In this paper, we focus on forest recovery on marginal land, and show that there is substantial inaccuracy and discrepancy in the literature concerning carbon accumulation. We find that uncertainty in carbon accumulation occurs in estimations of carbon stocks and models of carbon dynamics over time. We suggest that analyses to date have been largely unsuccessful at determining reliable trends in site recovery due to broad land use categories, a failure to consider the effect of current and post-restoration management, and problems with meta-analysis. Understanding of C recovery could be greatly improved with increased data collection on pre-restoration site quality, prior land use history, and management practices as well as increased methodological standardization. Finally, given the current and likely future uncertainty in C dynamics, we recommend carbon mitigation potential should not be the only environmental service driving land use decisions on marginal lands.

Distribution Locational Marginal Pricing for Optimal Electric Vehicle Charging Management

DEFF Research Database (Denmark)

Li, Ruoyang; Wu, Qiuwei; Oren, Shmuel S.

2013-01-01

This paper presents an integrated distribution locational marginal pricing (DLMP) method designed to alleviate congestion induced by electric vehicle (EV) loads in future power systems. In the proposed approach, the distribution system operator (DSO) determines distribution locational marginal...... shown that the socially optimal charging schedule can be implemented through a decentralized mechanism where loads respond autonomously to the posted DLMPs by maximizing their individual net surplus...

The marginal fit of selective laser melting-fabricated metal crowns: an in vitro study.

Science.gov (United States)

Xu, Dan; Xiang, Nan; Wei, Bin

2014-12-01

The selective laser melting technique is attracting interest in prosthetic dentistry. The marginal fit is a key criterion for fixed restorations. The purpose of the study was to evaluate the marginal fit of cast cobalt-chromium alloy crowns versus the fit of selective laser melting-fabricated crowns. The marginal gap widths of 36 single crowns (18 selective laser melting-fabricated cobalt-chromium metal crowns and 18 cobalt-chromium cast crowns) were determined with a silicone replica technique. Each crown specimen was cut into 4 sections, and the marginal gap width of each cross section was evaluated by stereomicroscopy (× 100). The Student t test was used to evaluate whether significant differences occurred in the marginal gap widths between the selective laser melting-fabricated and cast cobalt-chromium metal crowns (α=.05). The mean marginal gap width of the cast crowns (170.19 μm) was significantly wider than that of the selective laser melting-fabricated crowns (102.86 μm). Selective laser melting-fabricate cobalt-chromium dental crowns found improved marginal gap widths compared with traditional cast crowns. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Refining MARGINS Mini-Lessons Using Classroom Observations

Science.gov (United States)

Iverson, E. A.; Manduca, C. A.; McDaris, J. R.; Lee, S.

2009-12-01

One of the challenges that we face in developing teaching materials or activities from research findings is testing the materials to determine that they work as intended. Traditionally faculty develop material for their own class, notice what worked and didn’t, and improve them the next year. However, as we move to a community process of creating and sharing teaching materials, a community-based process for testing materials is appropriate. The MARGINS project has piloted such a process for testing teaching materials and activities developed as part of its mini-lesson project (http://serc.carleton.edu/margins/index.html). Building on prior work developing mechanisms for community review of teaching resources (e.g. Kastens, 2002; Hancock and Manduca, 2005; Mayhew and Hall, 2007), the MARGINS evaluation team developed a structured classroom observation protocol. The goals of field testing are to a) gather structured, consistent feedback for the lesson authors based on classroom use; b) guide reviewers of these lessons to reflect on research-based educational practice as a framework for their comments; c) collect information on the data and observations that the reviewer used to underpin their review; d) determine which mini-lessons are ready to be made widely available on the website. The protocol guides faculty observations on why they used the activity, the effectiveness of the activity in their classroom, the success of the activity in leading to the desired learning, and what other faculty need to successfully use the activity. Available online (http://serc.carleton.edu/margins/protocol.html), the protocol can be downloaded and completed during instruction with the activity. In order to encourage review of mini-lessons using the protocol, a workshop focused on review and revision of activities was held in May 2009. In preparation for the workshop, 13 of the 28 participants chose to field test a mini-lesson prior to the workshop and reported that they found this

Distributions with given marginals and statistical modelling

CERN Document Server

Fortiana, Josep; Rodriguez-Lallena, José

2002-01-01

This book contains a selection of the papers presented at the meeting `Distributions with given marginals and statistical modelling', held in Barcelona (Spain), July 17-20, 2000. In 24 chapters, this book covers topics such as the theory of copulas and quasi-copulas, the theory and compatibility of distributions, models for survival distributions and other well-known distributions, time series, categorical models, definition and estimation of measures of dependence, monotonicity and stochastic ordering, shape and separability of distributions, hidden truncation models, diagonal families, orthogonal expansions, tests of independence, and goodness of fit assessment. These topics share the use and properties of distributions with given marginals, this being the fourth specialised text on this theme. The innovative aspect of the book is the inclusion of statistical aspects such as modelling, Bayesian statistics, estimation, and tests.

Do Medicare Advantage Plans Select Enrollees in Higher Margin Clinical Categories?

Science.gov (United States)

Newhouse, Joseph P.; McWilliams, J. Michael; Price, Mary; Huang, Jie; Fireman, Bruce; Hsu, John

2013-01-01

The CMS-HCC risk adjustment system for Medicare Advantage (MA) plans calculates weights, which are effectively relative prices, for beneficiaries with different observable characteristics. To do so it uses the relative amounts spent per beneficiary with those characteristics in Traditional Medicare (TM). For multiple reasons one might expect relative amounts in MA to differ from TM, thereby making some beneficiaries more profitable to treat than others. Much of the difference comes from differences in how TM and MA treat different diseases or diagnoses. Using data on actual medical spending from two MA-HMO plans, we show that the weights calculated from MA costs do indeed differ from those calculated using TM spending. One of the two plans (Plan 1) is more typical of MA-HMO plans in that it contracts with independent community providers, while the other (Plan 2) is vertically integrated with care delivery. We calculate margins, or Average Revenue/Average Cost, for Medicare beneficiaries in the two plans who have one of 48 different combinations of medical conditions. The two plans’ margins for these 48 conditions are correlated (r=0.39, pincentive for selection by HCC. Nonetheless, we find no evidence of overrepresentation of beneficiaries in high margin HCC’s in either plan. Nor, using the margins from Plan 1, the more typical plan, do we find evidence of overrepresentation of high margin HCC’s in Medicare more generally. These results do not permit a conclusion on overall social efficiency, but we note that selection according to margin could be socially efficient. In addition, our findings suggest there are omitted interaction terms in the risk adjustment model that Medicare currently uses. PMID:24308879

The Magmatic Budget of Rifted Margins: is it Related to Inheritance?

Science.gov (United States)

Manatschal, G.; Tugend, J.; Gillard, M.; Sauter, D.

2017-12-01

High quality reflection and refraction seismic surveys show a divergent style of margin architecture often referred to as magma-poor or magma-rich. More detailed studies show, however, that the evolution of these margins can be similar, despite the variable quantity and distribution of magmatism. These observations suggest that simple relations between magmatic and extensional systems are inappropriate to describe the magmatic history of rifted margins. Moreover, the study of magmatic additions indicates that they may occur, prior to, during or after lithospheric breakup. Furthermore, the observation that the magmatic budget may change very abruptly along strike and across the margin is difficult to reconcile with the occurrence of plumes or other deep-seated large-scale mantle phenomena only. These overall observations result in questions on how magmatic and tectonic processes are interacting during rifting and lithospheric breakup and on how far the inherited composition and temperature of the decompressing mantle may control the magmatic budget during rifting. In our presentation we will review examples from present-day and fossil rifted margins to discuss their structural and magmatic evolution and whether they are considered as magma-rich or magma-poor. The key questions that we aim to address are: 1) whether decompression melting is the driving force, or rather the consequence of extension, 2) how far the magmatic budget is controlled by inherited mantle composition and temperature, and 3) how important magma storage is during initial stages of rifting. Eventually, we will discuss to what extent the evolution of margins may reflect the interplay between inheritance (innate/"genetic code") and the actual physical processes (acquired/external factors).

Breast Conservation Therapy: The Influence of Molecular Subtype and Margins

International Nuclear Information System (INIS)

Demirci, Senem; Broadwater, Gloria; Marks, Lawrence B.; Clough, Robert; Prosnitz, Leonard R.

2012-01-01

Purpose: To evaluate treatment results and prognostic factors, especially margin status and molecular subtype, in early-stage breast cancer patients treated with breast conservation therapy (BCT). Methods and Materials: The records of 1,058 Stage I or II breast cancer patients treated with BCT (surgical excision plus radiotherapy) at Duke University Medical Center, Durham, North Carolina, from 1985–2005 were retrospectively reviewed. Conventional receptor analyses were used as surrogate markers for molecular subtype classification (luminal A, luminal B, Her2 positive, and basal like). Actuarial estimates of overall survival (OS), cause-specific survival (CSS), failure-free survival, and locoregional control (LRC) were computed by use of Kaplan-Meier plots. We analyzed prognostic variables for significance using Cox proportional hazards univariate and multivariate analysis. The study was approved by the Duke University Medical Center Institutional Review Board. Results: The median age of the patients was 56 years (range, 18–89 years). Of the patients, 80% had T1 disease and 66% N0 disease pathologically. With a median follow-up of 9.8 years, an in-breast recurrence developed in 53 patients and 10 patients had nodal failure. For all patients, the 10-year CSS rate was 94%; LRC rate, 94%; and failure-free survival rate, 88%. Luminal A patients had a CSS rate of 95% and LRC rate of 99%. Basal-type patients appeared to do worse, with regard to both CSS rate (74%) and LRC rate (76%), but the numbers were small and the difference was not statistically significant. LRC rates of patients with negative margins (widely negative, close, and extent of margin not known) were virtually identical (93%, 96%, and 94%, respectively). Those with positive margins appeared to fare slightly worse based on LRC rate (88%), but again, the numbers were small and the difference was not statistically significant. Conclusions: BCT remains the treatment of choice for early-stage breast cancer

An Investigation of Rotorcraft Stability-Phase Margin Requirements in Hover

Science.gov (United States)

Blanken, Chris L.; Lusardi, Jeff A.; Ivler, Christina M.; Tischler, Mark B.; Hoefinger, Marc T.; Decker, William A.; Malpica, Carlos A.; Berger, Tom; Tucker, George E.

2009-01-01

A cooperative study was performed to investigate the handling quality effects from reduced flight control system stability margins, and the trade-offs with higher disturbance rejection bandwidth (DRB). The piloted simulation study, perform on the NASA-Ames Vertical Motion Simulator, included three classes of rotorcraft in four configurations: a utility-class helicopter; a medium-lift helicopter evaluated with and without an external slung load; and a large (heavy-lift) civil tiltrotor aircraft. This large aircraft also allowed an initial assessment of ADS-33 handling quality requirements for an aircraft of this size. Ten experimental test pilots representing the U.S. Army, Marine Corps, NASA, rotorcraft industry, and the German Aerospace Center (DLR), evaluated the four aircraft configurations, for a range of flight control stability-margins and turbulence levels, while primarily performing the ADS-33 Hover and Lateral Reposition MTEs. Pilot comments and aircraft-task performance data were analyzed. The preliminary stability margin results suggest higher DRB and less phase margin cases are preferred as the aircraft increases in size. Extra care will need to be taken to assess the influence of variability when nominal flight control gains start with reduced margins. Phase margins as low as 20-23 degrees resulted in low disturbance-response damping ratios, objectionable oscillations, PIO tendencies, and a perception of an incipient handling qualities cliff. Pilot comments on the disturbance response of the aircraft correlated well to the DRB guidelines provided in the ADS-33 Test Guide. The A D-3S3 mid-term response-to-control damping ratio metrics can be measured and applied to the disturbance-response damping ratio. An initial assessment of LCTR yaw bandwidth shows the current Level 1 boundary needs to be relaxed to help account for a large pilot off-set from the c.g. Future efforts should continue to investigate the applicability/refinement of the current ADS-33

Breast Conservation Therapy: The Influence of Molecular Subtype and Margins

Energy Technology Data Exchange (ETDEWEB)

Demirci, Senem, E-mail: senem.demirci@ege.edu.tr [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Department of Radiation Oncology, Ege University Faculty of Medicine, Izmir (Turkey); Broadwater, Gloria [Department of Biostatistics and Bioinformatics, Duke Cancer Institute, Durham, NC (United States); Cancer and Leukemia Group B Statistical Center, Duke Cancer Institute, Durham, NC (United States); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC (United States); Clough, Robert; Prosnitz, Leonard R. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

2012-07-01

Purpose: To evaluate treatment results and prognostic factors, especially margin status and molecular subtype, in early-stage breast cancer patients treated with breast conservation therapy (BCT). Methods and Materials: The records of 1,058 Stage I or II breast cancer patients treated with BCT (surgical excision plus radiotherapy) at Duke University Medical Center, Durham, North Carolina, from 1985-2005 were retrospectively reviewed. Conventional receptor analyses were used as surrogate markers for molecular subtype classification (luminal A, luminal B, Her2 positive, and basal like). Actuarial estimates of overall survival (OS), cause-specific survival (CSS), failure-free survival, and locoregional control (LRC) were computed by use of Kaplan-Meier plots. We analyzed prognostic variables for significance using Cox proportional hazards univariate and multivariate analysis. The study was approved by the Duke University Medical Center Institutional Review Board. Results: The median age of the patients was 56 years (range, 18-89 years). Of the patients, 80% had T1 disease and 66% N0 disease pathologically. With a median follow-up of 9.8 years, an in-breast recurrence developed in 53 patients and 10 patients had nodal failure. For all patients, the 10-year CSS rate was 94%; LRC rate, 94%; and failure-free survival rate, 88%. Luminal A patients had a CSS rate of 95% and LRC rate of 99%. Basal-type patients appeared to do worse, with regard to both CSS rate (74%) and LRC rate (76%), but the numbers were small and the difference was not statistically significant. LRC rates of patients with negative margins (widely negative, close, and extent of margin not known) were virtually identical (93%, 96%, and 94%, respectively). Those with positive margins appeared to fare slightly worse based on LRC rate (88%), but again, the numbers were small and the difference was not statistically significant. Conclusions: BCT remains the treatment of choice for early-stage breast cancer

Clinical Effect of Dental Adhesive on Marginal Integrity in Class I And Class II Resin-Composite Restorations

Directory of Open Access Journals (Sweden)

Manchorova-Veleva Neshka A.

2015-12-01

Full Text Available BACKGROUND: Dental adhesives are believed to influence marginal adaptation and marginal discoloration when used under posterior resin-based composite restorations. Studies on the latest adhesive systems reveal that the group of the three-step etch-and-rinse adhesive (3-E&RA and the one-step self-etch adhesive (1-SEA have entirely different bonding mechanisms, as well as different bond strength and resistance to chemical, thermal and mechanical factors. STUDY OBJECTIVES: A hypothesis that a 1-SEA would result in greater enamel marginal discoloration and poorer marginal adaptation than a 3-E&RA was tested. MATERIAL AND METHODS: One hundred restorations were placed with a 1-SEA and 100 restorations with a 3-E&RA. Teeth were restored with Filtek Supreme nanofilled resin-composite and were evaluated for marginal adaptation and marginal discoloration at baseline, and 6 months, 12 months, and 36 months postoperatively. RESULTS: The statistical analysis revealed significant differences in marginal integrity between test groups. The 1-SEA resulted in greater enamel marginal discoloration and poorer marginal adaptation than the 3-E&RA at any recall time. CONCLUSIONS: Marginal adaptation and marginal discoloration depend on the type of dentin adhesive used. The restorations with Filtek Supreme and Scotchbond MP are better than the restorations with Adper Prompt L-Pop with regard to the marginal adaptation and marginal discoloration at 6-, 12- and 36-month evaluations.

Estimación de la demanda de agua para uso residencial urbano usando un modelo discreto-continuo y datos desagregados a nivel de hogar: el caso de la ciudad de Manizales, Colombia

OpenAIRE

Darío Jiménez; Sergio Orrego; Felipe Vásquez; Roberto Ponce

2017-01-01

En el presente trabajo se estima la demanda de agua para uso residencial urbano en la ciudad de Manizales, Colombia, usando un modelo estructural que considera tanto la elección discreta del bloque de consumo como la elección continua sobre la cantidad a consumir. La demanda se estimó econométricamente utilizando una base de datos única para un país en desarrollo y que contiene información completa sobre el consumo mensual de agua, el tamaño del hogar, las características de la vivienda, vari...

Quantifying the margin sharpness of lesions on radiological images for content-based image retrieval

International Nuclear Information System (INIS)

Xu Jiajing; Napel, Sandy; Greenspan, Hayit; Beaulieu, Christopher F.; Agrawal, Neeraj; Rubin, Daniel

2012-01-01

Purpose: To develop a method to quantify the margin sharpness of lesions on CT and to evaluate it in simulations and CT scans of liver and lung lesions. Methods: The authors computed two attributes of margin sharpness: the intensity difference between a lesion and its surroundings, and the sharpness of the intensity transition across the lesion boundary. These two attributes were extracted from sigmoid curves fitted along lines automatically drawn orthogonal to the lesion margin. The authors then represented the margin characteristics for each lesion by a feature vector containing histograms of these parameters. The authors created 100 simulated CT scans of lesions over a range of intensity difference and margin sharpness, and used the concordance correlation between the known parameter and the corresponding computed feature as a measure of performance. The authors also evaluated their method in 79 liver lesions (44 patients: 23 M, 21 F, mean age 61) and 58 lung nodules (57 patients: 24 M, 33 F, mean age 66). The methodology presented takes into consideration the boundary of the liver and lung during feature extraction in clinical images to ensure that the margin feature do not get contaminated by anatomy other than the normal organ surrounding the lesions. For evaluation in these clinical images, the authors created subjective independent reference standards for pairwise margin sharpness similarity in the liver and lung cohorts, and compared rank orderings of similarity used using our sharpness feature to that expected from the reference standards using mean normalized discounted cumulative gain (NDCG) over all query images. In addition, the authors compared their proposed feature with two existing techniques for lesion margin characterization using the simulated and clinical datasets. The authors also evaluated the robustness of their features against variations in delineation of the lesion margin by simulating five types of deformations of the lesion margin

Late differentiation of proximal and distal margins in the Gulf of Aden

Science.gov (United States)

Bache, F.; Leroy, S.; D'Acremont, E.; Autin, J.; Watremez, L.; Rouzo, S.

2009-04-01

Non-volcanic passive margins are usually described in three different domains (Boillot et al., 1988), namely (1) the continental domain, where the basement is structured in a series of basins and basement rises, (2) the true oceanic domain, where the bathymetry is relatively smooth, and (3) in between them, a transitional domain referred to as the oceanic-continental transition (OCT), where the basement is partly composed of exhumed mantle. The Gulf of Aden is a young and narrow oceanic basin formed in Oligo-Miocene time between the rifted margins of the Arabian and Somalian plates. The distal margin and particularly the OCT domain were previously studied considering a large set of data (Leroy et al., 2004; d'Acremont et al., 2005; d'Acremont et al., 2006; Autin, 2008). This study focalises on the sedimentary cover identified on seismic reflexion profiles acquired during Encens-Sheba (2000) and Encens (2006) cruises. Sedimentary stratal pattern and seismic facies succession suggest that the differentiation between the proximal and the distal margins occurred very late in the formation of the margin, after the deposition of ~2 km of "syn-OCT" sediments which filled the distal margin grabens. A high position of the proximal and distal margins during rifting and "syn-OCT" sediments deposition could be proposed. The major implication of this evolution should be a shallow nature of "syn-OCT" deposits. The lack of boreholes doesn't permit to affirm this last point. Comparable observations have been described on other passive margins (Moulin, 2003; Moulin et al., 2005; Labails, 2007; Aslanian et al., 2008; Bache, 2008). For some authors, it shows the persistence of a deep thermal anomaly during the early history of the margin (Steckler et al., 1988; Dupré et al., 2007). These observations could be a common characteristic of passive margins evolution and are of major interest for petroleum exploration. Aslanian, D., M. Moulin, O. J.L., P. Unternehr, F. Bache, I. Contrucci

Assessment of tsunami hazard to the U.S. Atlantic margin

Science.gov (United States)

ten Brink, Uri S.; Chaytor, Jason; Geist, Eric L.; Brothers, Daniel S.; Andrews, Brian D.

2014-01-01

Tsunami hazard is a very low-probability, but potentially high-risk natural hazard, posing unique challenges to scientists and policy makers trying to mitigate its impacts. These challenges are illustrated in this assessment of tsunami hazard to the U.S. Atlantic margin. Seismic activity along the U.S. Atlantic margin in general is low, and confirmed paleo-tsunami deposits have not yet been found, suggesting a very low rate of hazard. However, the devastating 1929 Grand Banks tsunami along the Atlantic margin of Canada shows that these events continue to occur. Densely populated areas, extensive industrial and port facilities, and the presence of ten nuclear power plants along the coast, make this region highly vulnerable to flooding by tsunamis and therefore even low-probability events need to be evaluated.

On the marginally relevant operator in z=2 Lifshitz holography

International Nuclear Information System (INIS)

Holsheimer, Kristian

2014-01-01

We study holographic renormalization and RG flow in a strongly-coupled Lifshitz-type theory in 2+1 dimensions with dynamical exponent z=2. The bottom-up gravity dual we use is 3+1 dimensional Einstein gravity coupled to a massive vector field. This model contains a marginally relevant operator around the Lifshitz fixed point. We show how holographic renormalization works in the presence of this marginally relevant operator without the need to introduce explicitly cutoff-dependent counterterms. A simple closed-form expression is found for the renormalized on-shell action. We also discuss how asymptotically Lifshitz geometries flow to AdS in the interior due to the marginally relevant operator. We study the behavior of the renormalized entanglement entropy and confirm that it decreases monotonically along the Lifshitz-to-AdS RG flow

Masculinity at the margins

DEFF Research Database (Denmark)

Jensen, Sune Qvotrup

2010-01-01

and other types of material. Taking the concepts of othering, intersectionality and marginality as point of departure the article analyses how these young men experience othering and how they react to it. One type of reaction, described as stylization, relies on accentuating the latently positive symbolic...... of critique although in a masculinist way. These reactions to othering represent a challenge to researchers interested in intersectionality and gender, because gender is reproduced as a hierarchical form of social differentiation at the same time as racism is both reproduced and resisted....

Contributions to knowledge of the continental margin of Uruguay. Description of background samples in the continental margin of Uruguay

International Nuclear Information System (INIS)

Preciozzi, F

2015-01-01

This study provide data concerning of the background sediments of the continental margin of Uruguay. There were carried out different works with witnesses in order to extract various sediment samples from the continental shelf

MODELADO DEL PRECIO SPOT DE LA ELECTRICIDAD EN BRASIL USANDO UNA RED NEURONAL AUTORREGRESIVA ELECTRICITY SPOT PRICE MODELLING IN BRASIL USING AN AUTOREGRESSIVE NEURAL NETWORK

Directory of Open Access Journals (Sweden)

Juan D Velásquez

2008-12-01

Full Text Available Una red neuronal autorregresiva es estimada para el precio mensual brasileño de corto plazo de la electricidad, la cual describe mejor la dinámica de los precios que un modelo lineal autorregresivo y que un perceptrón multicapa clásico que usan las mismas entradas y neuronas en la capa oculta. El modelo propuesto es especificado usando un procedimiento estadístico basado en el contraste del radio de verosimilitud. El modelo pasa una batería de pruebas de diagnóstico. El procedimiento de especificación propuesto permite seleccionar el número de unidades en la capa oculta y las entradas a la red neuronal, usando pruebas estadísticas que tienen en cuenta la cantidad de los datos y el ajuste del modelo a la serie de precios. La especificación del modelo final demuestra que el precio para el próximo mes es una función no lineal del precio actual, de la energía afluente actual y de la energía almacenada en el embalse equivalente en el mes actual y dos meses atrás.An autoregressive neural network model is estimated for the monthly Brazilian electricity spot price, which describes the prices dynamics better than a linear autoregressive model and a classical multilayer perceptron using the same input and neurons in the hidden layer. The proposed model is specified using a statistical procedure based on a likelihood ratio test. The model passes a battery of diagnostic tests. The proposed specification procedure allows us to select the number of units in hidden layer and the inputs to the neural network based on statistical tests, taking into account the number of data and the model fitting to the price time series. The final model specification demonstrates that the price for the next month is a nonlinear function of the current price, the current energy inflow, and the energy saved in the equivalent reservoir in the current month and two months ago.

Hippocampal sparing radiotherapy for pediatric medulloblastoma: impact of treatment margins and treatment technique.

Science.gov (United States)

Brodin, N Patrik; Munck af Rosenschöld, Per; Blomstrand, Malin; Kiil-Berthlesen, Anne; Hollensen, Christian; Vogelius, Ivan R; Lannering, Birgitta; Bentzen, Søren M; Björk-Eriksson, Thomas

2014-04-01

We investigated how varying the treatment margin and applying hippocampal sparing and proton therapy impact the risk of neurocognitive impairment in pediatric medulloblastoma patients compared with current standard 3D conformal radiotherapy. We included 17 pediatric medulloblastoma patients to represent the variability in tumor location relative to the hippocampal region. Treatment plans were generated using 3D conformal radiotherapy, hippocampal sparing intensity-modulated radiotherapy, and spot-scanned proton therapy, using 3 different treatment margins for the conformal tumor boost. Neurocognitive impairment risk was estimated based on dose-response models from pediatric CNS malignancy survivors and compared among different margins and treatment techniques. Mean hippocampal dose and corresponding risk of cognitive impairment were decreased with decreasing treatment margins (P < .05). The largest risk reduction, however, was seen when applying hippocampal sparing proton therapy-the estimated risk of impaired task efficiency (95% confidence interval) was 92% (66%-98%), 81% (51%-95%), and 50% (30%-70%) for 3D conformal radiotherapy, intensity-modulated radiotherapy, and proton therapy, respectively, for the smallest boost margin and 98% (78%-100%), 90% (60%-98%), and 70% (39%-90%) if boosting the whole posterior fossa. Also, the distance between the closest point of the planning target volume and the center of the hippocampus can be used to predict mean hippocampal dose for a given treatment technique. We estimate a considerable clinical benefit of hippocampal sparing radiotherapy. In choosing treatment margins, the tradeoff between margin size and risk of neurocognitive impairment quantified here should be considered.

Study Suggests Smaller Melanoma Excision Margins May Be Option for Some Patients

Science.gov (United States)

A randomized controlled trial of patients with stage IIA–C cutaneous melanoma thicker than 2-mm found that a 2-cm surgical resection margin is sufficient and is as safe for patients as a 4-cm margin.

Studies on correlation of positive surgical margin with clinicopathological factors and prognoses in breast conserving surgery

International Nuclear Information System (INIS)

Nishimura, Reiki; Nagao, Kazuharu; Miyayama, Haruhiko

1999-01-01

Out of 484 cases with breast conserving surgery between April 1989 and March 1999, surgical procedures of 34 cases were changed to total mastectomy due to positive surgical margins. In this study we evaluated a clinical significance of surgical margin in relation to clinicopathological factors and prognoses. Ninety-nine cases (20.5%) had positive margins that were judged when cancer cells existed within 5 mm from margin. In multivariate analysis of factors for surgical margin, EIC-comedo status, ly, located site, proliferative activity, and age were significant and independent factors. Regarding local recurrence, positive margin, age, ER and proliferative activity were significant factors in multivariate analysis, especially in cases not receiving postoperative radiation therapy. Radiation therapy may be beneficial for patients with positive surgical margin. And patients with breast recurrence alone had significantly higher survival rates. Therefore, it is suggested that surgical margin may not reflect survival, although it is a significant factor for local recurrence. (author)

Studies on correlation of positive surgical margin with clinicopathological factors and prognoses in breast conserving surgery

Energy Technology Data Exchange (ETDEWEB)

Nishimura, Reiki; Nagao, Kazuharu; Miyayama, Haruhiko [Kumamoto City Hospital (Japan)

1999-09-01

Out of 484 cases with breast conserving surgery between April 1989 and March 1999, surgical procedures of 34 cases were changed to total mastectomy due to positive surgical margins. In this study we evaluated a clinical significance of surgical margin in relation to clinicopathological factors and prognoses. Ninety-nine cases (20.5%) had positive margins that were judged when cancer cells existed within 5 mm from margin. In multivariate analysis of factors for surgical margin, EIC-comedo status, ly, located site, proliferative activity, and age were significant and independent factors. Regarding local recurrence, positive margin, age, ER and proliferative activity were significant factors in multivariate analysis, especially in cases not receiving postoperative radiation therapy. Radiation therapy may be beneficial for patients with positive surgical margin. And patients with breast recurrence alone had significantly higher survival rates. Therefore, it is suggested that surgical margin may not reflect survival, although it is a significant factor for local recurrence. (author)

Specimen Shrinkage and Its Influence on Margin Assessment in Breast Cancer

Directory of Open Access Journals (Sweden)

Badrul H. Yeap

2007-07-01

Conclusion: Breast specimens undergo shrinkage after histological fixation, losing more than a third of their original closest free margin, whilst the tumour itself does not shrink substantially. This phenomenon has vital implications in the accuracy of margin analysis and consequent decisions on further management, including re-operation and the institution of adjuvant radiotherapy.

The Short- and Long-Run Marginal Cost Curve: A Pedagogical Note.

Science.gov (United States)

Sexton, Robert L.; And Others

1993-01-01

Contends that the standard description of the relationship between the long-run marginal cost curve and the short-run marginal cost curve is often misleading and imprecise. Asserts that a sampling of college-level textbooks confirms this confusion. Provides a definition and instructional strategy that can be used to promote student understanding…

Coming in from the Margin: Research Practices, Representation and the Ordinary

Science.gov (United States)

Greiner, Karen P.

2010-01-01

This essay explores issues of marginality and representation in research, which emerged during life history interviews with Tammi, an "ordinary" woman living in Appalachia. I examine how my research practices, namely my thirst for drama and marginality, nearly silenced the preferred stories of the woman who shared her life with me. I…

Isolated marginal facial nerve paresis after TMJ discopexy: a case report.

Science.gov (United States)

Reychler, H; Mahy, P

2011-01-01

Isolated marginal facial nerve paresis after TMJ discopexy: a case report. This is the first report of a transient, isolated marginal facial nerve paresis after temporomandibular joint arthrotomy. The paresis seems to have resulted from a crush lesion by Backhaus forceps, placed transcutaneously during the operation to distract the intra-articular space.

Gravity anomalies over a segment of Pratap ridge and adjoining shelf margin basin, western continental margin of India

Digital Repository Service at National Institute of Oceanography (India)

Subrahmanyam, V.; Rao, D.G.; Ramprasad, T.; KameshRaju, K.A.; Rao, M.G.

Bathymetric and gravity data totalling 2000 line km on the continental margin off Goa and Mulki, west of India have been studied. The free-air gravity anomalies vary between -60 to 25 mgals with prominent NNW-SSE trends in the outer shelf region...

Relief for marginal wells is better than energy tax. [United States: policy

Energy Technology Data Exchange (ETDEWEB)

Swords, J.; Wilson, D. (Coopers and Lybrand (United States))

1993-04-01

By increasing production costs and reducing petroleum prices, President Bill Clinton's proposed energy tax would increase marginal well abandonments and hasten the decline of the US oil and gas industry. Instead, the US needs tax law changes to help counteract the increasing number of oil and gas well abandonments in the lower 48 states. The proposed tax would create potential difficulties, while three incentives could be introduced to reduce abandonments and at the same time preserve US government tax revenues that otherwise would be lost. Eliminating the net income limitation on percentage depletion allowances on wells that would otherwise be abandoned would be a great help for marginal well operators. Extended enhanced oil recovery (EOR) credits and broader investment tax credits could also serve the dual purpose of keeping marginal wells operating longer and generating more federal tax revenues. A marginal well investment tax credit should be provided that is not just a credit for incremented investments that exceed investment in prior years. An investment tax credit based on out-of-pocket costs of production, targeted for marginal wells, would be an important incentive to invest in, and continue to maintain, these properties. (author)

Identifying Gaps in the Performance of Pediatric Trainees Who Receive Marginal/Unsatisfactory Ratings.

Science.gov (United States)

Li, Su-Ting T; Tancredi, Daniel J; Schwartz, Alan; Guillot, Ann; Burke, Ann; Trimm, R Franklin; Guralnick, Susan; Mahan, John D; Gifford, Kimberly A

2018-01-01

To perform a derivation study to determine in which subcompetencies marginal/unsatisfactory pediatric residents had the greatest deficits compared with their satisfactorily performing peers and which subcompetencies best discriminated between marginal/unsatisfactory and satisfactorily performing residents. Multi-institutional cohort study of all 21 milestones (rated on four or five levels) reported to the Accreditation Council for Graduate Medical Education, and global marginal/unsatisfactory versus satisfactory performance reported to the American Board of Pediatrics. Data were gathered in 2013-2014. For each level of training (postgraduate year [PGY] 1, 2, and 3), mean differences between milestone levels of residents with marginal/unsatisfactory and satisfactory performance adjusted for clustering by program and C-statistics (area under receiver operating characteristic curve) were calculated. A Bonferroni-corrected significance threshold of .0007963 was used to account for multiple comparisons. Milestone and overall performance evaluations for 1,704 pediatric residents in 41 programs were obtained. For PGY1s, two subcompetencies had almost a one-point difference in milestone levels between marginal/unsatisfactory and satisfactory trainees and outstanding discrimination (≥ 0.90): organize/prioritize (0.93; C-statistic: 0.91) and transfer of care (0.97; C-statistic: 0.90). The largest difference between marginal/unsatisfactory and satisfactory PGY2s was trustworthiness (0.78). The largest differences between marginal/unsatisfactory and satisfactory PGY3s were ethical behavior (1.17), incorporating feedback (1.03), and professionalization (0.96). For PGY2s and PGY3s, no subcompetencies had outstanding discrimination. Marginal/unsatisfactory pediatric residents had different subcompetency gaps at different training levels. While PGY1s may have global deficits, senior residents may have different performance deficiencies requiring individualized counseling and

Impact of Close and Positive Margins in Transoral Laser Microsurgery for Tis-T2 Glottic Cancer.

Science.gov (United States)

Fiz, Ivana; Mazzola, Francesco; Fiz, Francesco; Marchi, Filippo; Filauro, Marta; Paderno, Alberto; Parrinello, Giampiero; Piazza, Cesare; Peretti, Giorgio

2017-01-01

Transoral laser microsurgery (TLM) represents one of the most effective treatment strategies for Tis-T2 glottic squamous cell carcinomas (SCC). The prognostic influence of close/positive margins is still debated, and the role of narrow band imaging (NBI) in their intraoperative definition is still to be validated on large cohort of patients. This study analyzed the influence of margin status on recurrence-free survival (RFS) and disease-specific survival (DSS). We retrospectively studied 507 cases of pTis-T1b (Group A) and 127 cases of pT2 (Group B) glottic SCC. We identified the following margin status: negative ( n  = 232), close superficial ( n  = 79), close deep (CD) ( n  = 35), positive single superficial ( n  = 146), positive multiple superficial ( n  = 94), and positive deep ( n  = 48) and analyzed their impact on RFS and DSS. Close margins were defined by tumor-margin distance <1 mm. Pre-TLM margins were defined by white light in 323 patients, whereas NBI was employed in 311 patients. In Group A, DSS and RFS were reduced in positive multiple superficial and positive deep margins (DSS = 96.1 and 97%, both p  < 0.05; RFS = 72%, p  < 0.001 and 75.8%, p  < 0.01). In Group B, DSS was reduced in positive multiple superficial margins (82.4%, p  < 0.05). RFS was reduced in positive single superficial, positive multiple superficial, and positive deep margins (62.5, 41.2, and 53.3%, p  < 0.01). In the entire population, RFS was reduced in CD margins (77.1%, p  < 0.05). Use of NBI led to improvement in RFS and DSS. The study indicates that close and positive single superficial margins do not affect DSS. By contrast, all types of margin positivity predict the occurrence of relapses, albeit with different likelihood, depending on stage/margin type. CD margins should be considered as a single risk factor. Use of NBI granted better intraoperative margins definition.

Early math intervention for marginalized students

DEFF Research Database (Denmark)

Overgaard, Steffen; Tonnesen, Pia Beck

2016-01-01

This study is one of more substudies in the project Early Math Intervention for Marginalized Students (TMTM2014). The paper presents the initial process of this substudy that will be carried out fall 2015. In the TMTM2014 project, 80 teachers, who completed a one week course in the idea of TMTM...

12 CFR 221.7 - Supplement: Maximum loan value of margin stock and other collateral.

Science.gov (United States)

2010-01-01

... value of margin stock and other collateral. (a) Maximum loan value of margin stock. The maximum loan... nonmargin stock and all other collateral. The maximum loan value of nonmargin stock and all other collateral... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Supplement: Maximum loan value of margin stock...

Quantifying motion for pancreatic radiotherapy margin calculation

International Nuclear Information System (INIS)

Whitfield, Gillian; Jain, Pooja; Green, Melanie; Watkins, Gillian; Henry, Ann; Stratford, Julie; Amer, Ali; Marchant, Thomas; Moore, Christopher; Price, Patricia

2012-01-01

Background and purpose: Pancreatic radiotherapy (RT) is limited by uncertain target motion. We quantified 3D patient/organ motion during pancreatic RT and calculated required treatment margins. Materials and methods: Cone-beam computed tomography (CBCT) and orthogonal fluoroscopy images were acquired post-RT delivery from 13 patients with locally advanced pancreatic cancer. Bony setup errors were calculated from CBCT. Inter- and intra-fraction fiducial (clip/seed/stent) motion was determined from CBCT projections and orthogonal fluoroscopy. Results: Using an off-line CBCT correction protocol, systematic (random) setup errors were 2.4 (3.2), 2.0 (1.7) and 3.2 (3.6) mm laterally (left–right), vertically (anterior–posterior) and longitudinally (cranio-caudal), respectively. Fiducial motion varied substantially. Random inter-fractional changes in mean fiducial position were 2.0, 1.6 and 2.6 mm; 95% of intra-fractional peak-to-peak fiducial motion was up to 6.7, 10.1 and 20.6 mm, respectively. Calculated clinical to planning target volume (CTV–PTV) margins were 1.4 cm laterally, 1.4 cm vertically and 3.0 cm longitudinally for 3D conformal RT, reduced to 0.9, 1.0 and 1.8 cm, respectively, if using 4D planning and online setup correction. Conclusions: Commonly used CTV–PTV margins may inadequately account for target motion during pancreatic RT. Our results indicate better immobilisation, individualised allowance for respiratory motion, online setup error correction and 4D planning would improve targeting.

Aggregate Settling Velocities in San Francisco Estuary Margins

Science.gov (United States)

Allen, R. M.; Stacey, M. T.; Variano, E. A.

2015-12-01

One way that humans impact aquatic ecosystems is by adding nutrients and contaminants, which can propagate up the food web and cause blooms and die-offs, respectively. Often, these chemicals are attached to fine sediments, and thus where sediments go, so do these anthropogenic influences. Vertical motion of sediments is important for sinking and burial, and also for indirect effects on horizontal transport. The dynamics of sinking sediment (often in aggregates) are complex, thus we need field data to test and validate existing models. San Francisco Bay is well studied and is often used as a test case for new measurement and model techniques (Barnard et al. 2013). Settling velocities for aggregates vary between 4*10-5 to 1.6*10-2 m/s along the estuary backbone (Manning and Schoellhamer 2013). Model results from South San Francisco Bay shoals suggest two populations of settling particles, one fast (ws of 9 to 5.8*10-4 m/s) and one slow (ws of Brand et al. 2015). While the open waters of San Francisco Bay and other estuaries are well studied and modeled, sediment and contaminants often originate from the margin regions, and the margins remain poorly characterized. We conducted a 24 hour field experiment in a channel slough of South San Francisco Bay, and measured settling velocity, turbulence and flow, and suspended sediment concentration. At this margin location, we found average settling velocities of 4-5*10-5 m/s, and saw settling velocities decrease with decreasing suspended sediment concentration. These results are consistent with, though at the low end of, those seen along the estuary center, and they suggest that the two population model that has been successful along the shoals may also apply in the margins.

Analysis and study on core power capability with margin method

International Nuclear Information System (INIS)

Liu Tongxian; Wu Lei; Yu Yingrui; Zhou Jinman

2015-01-01

Core power capability analysis focuses on the power distribution control of reactor within the given mode of operation, for the purpose of defining the allowed normal operating space so that Condition Ⅰ maneuvering flexibility is maintained and Condition Ⅱ occurrences are adequately protected by the reactor protection system. For the traditional core power capability analysis methods, such as synthesis method or advanced three dimension method, usually calculate the key safety parameters of the power distribution, and then verify that these parameters meet the design criteria. For PWR with on-line power distribution monitoring system, core power capability analysis calculates the most power level which just meets the design criteria. On the base of 3D FAC method of Westinghouse, the calculation model of core power capability analysis with margin method is introduced to provide reference for engineers. The core power capability analysis of specific burnup of Sanmen NPP is performed with the margin method. The results demonstrate the rationality of the margin method. The calculation model of the margin method not only helps engineers to master the core power capability analysis for AP1000, but also provides reference for engineers for core power capability analysis of other PWR with on-line power distribution monitoring system. (authors)

Establishing seismic design criteria to achieve an acceptable seismic margin

International Nuclear Information System (INIS)

Kennedy, R.P.

1997-01-01

In order to develop a risk based seismic design criteria the following four issues must be addressed: (1) What target annual probability of seismic induced unacceptable performance is acceptable? (2). What minimum seismic margin is acceptable? (3) Given the decisions made under Issues 1 and 2, at what annual frequency of exceedance should the Safe Shutdown Earthquake ground motion be defined? (4) What seismic design criteria should be established to reasonably achieve the seismic margin defined under Issue 2? The first issue is purely a policy decision and is not addressed in this paper. Each of the other three issues are addressed. Issues 2 and 3 are integrally tied together so that a very large number of possible combinations of responses to these two issues can be used to achieve the target goal defined under Issue 1. Section 2 lays out a combined approach to these two issues and presents three potentially attractive combined resolutions of these two issues which reasonably achieves the target goal. The remainder of the paper discusses an approach which can be used to develop seismic design criteria aimed at achieving the desired seismic margin defined in resolution of Issue 2. Suggestions for revising existing seismic design criteria to more consistently achieve the desired seismic margin are presented

Tectonostratigraphy of the Passive Continental Margin Offshore Indus Pakistan

Science.gov (United States)

Aslam, K.; Khan, M.; Liu, Y.; Farid, A.

2017-12-01

The tectonic evolution and structural complexities are poorly understood in the passive continental margin of the Offshore Indus of Pakistan. In the present study, an attempt has been made to interpret the structural trends and seismic stratigraphic framework in relation to the tectonics of the region. Seismic reflection data revealed tectonically controlled, distinct episodes of normal faulting representing rifting at different ages and transpression in the Late Eocene time. This transpression has resulted in the reactivation of the Pre-Cambrian basement structures. The movement of these basement structures has considerably affected the younger sedimentary succession resulting in push up structures resembling anticlines. The structural growth of the push-up structures was computed. The most remarkable tectonic setting in the region is represented by the normal faulting and by the basement uplift which divides the rifting and transpression stages. Ten mappable seismic sequences have been identified on the seismic records. A Jurassic aged paleo-shelf has also been identified on all regional seismic profiles which is indicative of Indian-African Plates separation during the Jurassic time. Furthermore, the backstripping technique was applied which has been proved to be a powerful technique to quantify subsidence/uplift history of rift-type passive continental margins. The back strip curves suggest that transition from an extensional rifted margin to transpression occurred during Eocene time (50-30 Ma). The backstripping curves show uplift had happened in the area. We infer that the uplift has occurred due to the movement of basement structures by the transpression movements of Arabian and Indian Plates. The present study suggests that the structural styles and stratigraphy of the Offshore Indus Pakistan were significantly affected by the tectonic activities during the separation of Gondwanaland in the Mesozoic and northward movement of the Indian Plate, post

Estudio comparativo de flujo de fluido a través de una placa de orificio usando las ecuaciones de Stokes y de Navier-Stokes

Directory of Open Access Journals (Sweden)

Miryam Lucía Guerra-Mazo

2016-05-01

Full Text Available Presenta los resultados de la comparación entre las ecuaciones de Stokes y de Navier-Stokes para la simulación del flujo de agua líquida, a condiciones atmosféricas, a través de una placa orificio concéntrica. A partir de los datos experimentales que fueron tomados en el banco de fluidos, se evaluaron las simulaciones de ambas ecuaciones, usando el software libre Freefem++cs, que se basa en el método de los elementos finitos; las variables evaluadas son velocidad y presión en un intervalo de tiempo. Al analizar los resultados obtenidos con las simulaciones y comparar con los datos experimentales se encontró que las ecuaciones de Navier-Stokes representan mejor el sistema que la ecuación de Stokes.

Rotor Design Options for Improving XV-15 Whirl-Flutter Stability Margins

Science.gov (United States)

Acree, C. W., Jr.; Peyran, R. J.; Johnson, Wayne

2004-01-01

Rotor design changes intended to improve tiltrotor whirl-flutter stability margins were analyzed. A baseline analytical model of the XV-15 was established, and then a thinner, composite wing was designed to be representative of a high-speed tiltrotor. The rotor blade design was modified to increase the stability speed margin for the thin-wing design. Small rearward offsets of the aerodynamic-center locus with respect to the blade elastic axis created large increases in the stability boundary. The effect was strongest for offsets at the outboard part of the blade, where an offset of the aerodynamic center by 10% of tip chord improved the stability margin by over 100 knots. Forward offsets of the blade center of gravity had similar but less pronounced effects. Equivalent results were seen for swept-tip blades. Appropriate combinations of sweep and pitch stiffness completely eliminated whirl flutter within the speed range examined; alternatively, they allowed large increases in pitch-flap coupling (delta-three) for a given stability margin. A limited investigation of the rotor loads in helicopter and airplane configuration showed only minor increases in loads.

"Resuscitation" of marginal liver allografts for transplantation with machine perfusion technology.

Science.gov (United States)

Graham, Jay A; Guarrera, James V

2014-08-01

As the rate of medically suitable donors remains relatively static worldwide, clinicians have looked to novel methods to meet the ever-growing demand of the liver transplant waiting lists worldwide. Accordingly, the transplant community has explored many strategies to offset this deficit. Advances in technology that target the ex vivo "preservation" period may help increase the donor pool by augmenting the utilization and improving the outcomes of marginal livers. Novel ex vivo techniques such as hypothermic, normothermic, and subnormothermic machine perfusion may be useful to "resuscitate" marginal organs by reducing ischemia/reperfusion injury. Moreover, other preservation techniques such as oxygen persufflation are explored as they may also have a role in improving function of "marginal" liver allografts. Currently, marginal livers are frequently discarded or can relegate the patient to early allograft dysfunction and primary non-function. Bench to bedside advances are rapidly emerging and hold promise for expanding liver transplantation access and improving outcomes. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Geophysical studies over the continental margins of the east coast of India

Digital Repository Service at National Institute of Oceanography (India)

Rao, T.C.S.; Rao, V.B.

. Continuity of surface and subsurface features from profile to profile is indicated. Two major structural elements - viz. The "Marginal High", situated at the foot of the continental slope and extending along the east coast of India, and the "Marginal Basin...

Exact marginality in open string field theory. A general framework

International Nuclear Information System (INIS)

Kiermaier, M.

2007-07-01

We construct analytic solutions of open bosonic string field theory for any exactly marginal deformation in any boundary conformal field theory when properly renormalized operator products of the marginal operator are given. We explicitly provide such renormalized operator products for a class of marginal deformations which include the deformations of flat D-branes in flat backgrounds by constant massless modes of the gauge field and of the scalar fields on the D-branes, the cosine potential for a space-like coordinate, and the hyperbolic cosine potential for the time-like coordinate. In our construction we use integrated vertex operators, which are closely related to finite deformations in boundary conformal field theory, while previous analytic solutions were based on unintegrated vertex operators. We also introduce a modified star product to formulate string field theory around the deformed background. (orig.)

Formulation, computation and improvement of steady state security margins in power systems. Part II: Results

International Nuclear Information System (INIS)

Echavarren, F.M.; Lobato, E.; Rouco, L.; Gomez, T.

2011-01-01

A steady state security margin for a particular operating point can be defined as the distance from this initial point to the secure operating limits of the system. Four of the most used steady state security margins are the power flow feasibility margin, the contingency feasibility margin, the load margin to voltage collapse, and the total transfer capability between system areas. This is the second part of a two part paper. Part I has proposed a novel framework of a general model able to formulate, compute and improve any steady state security margin. In Part II the performance of the general model is validated by solving a variety of practical situations in modern real power systems. Actual examples of the Spanish power system will be used for this purpose. The same computation and improvement algorithms outlined in Part I have been applied for the four security margins considered in the study, outlining the convenience of defining a general framework valid for the four of them. The general model is used here in Part II to compute and improve: (a) the power flow feasibility margin (assessing the influence of the reactive power generation limits in the Spanish power system), (b) the contingency feasibility margin (assessing the influence of transmission and generation capacity in maintaining a correct voltage profile), (c) the load margin to voltage collapse (assessing the location and quantity of loads that must be shed in order to be far away from voltage collapse) and (d) the total transfer capability (assessing the export import pattern of electric power between different areas of the Spanish system). (author)

Formulation, computation and improvement of steady state security margins in power systems. Part II: Results

Energy Technology Data Exchange (ETDEWEB)

Echavarren, F.M.; Lobato, E.; Rouco, L.; Gomez, T. [School of Engineering of Universidad Pontificia Comillas, C/Alberto Aguilera, 23, 28015 Madrid (Spain)

2011-02-15

A steady state security margin for a particular operating point can be defined as the distance from this initial point to the secure operating limits of the system. Four of the most used steady state security margins are the power flow feasibility margin, the contingency feasibility margin, the load margin to voltage collapse, and the total transfer capability between system areas. This is the second part of a two part paper. Part I has proposed a novel framework of a general model able to formulate, compute and improve any steady state security margin. In Part II the performance of the general model is validated by solving a variety of practical situations in modern real power systems. Actual examples of the Spanish power system will be used for this purpose. The same computation and improvement algorithms outlined in Part I have been applied for the four security margins considered in the study, outlining the convenience of defining a general framework valid for the four of them. The general model is used here in Part II to compute and improve: (a) the power flow feasibility margin (assessing the influence of the reactive power generation limits in the Spanish power system), (b) the contingency feasibility margin (assessing the influence of transmission and generation capacity in maintaining a correct voltage profile), (c) the load margin to voltage collapse (assessing the location and quantity of loads that must be shed in order to be far away from voltage collapse) and (d) the total transfer capability (assessing the export import pattern of electric power between different areas of the Spanish system). (author)

The effect of differentiated margin on futures market investors' behavior and structure An experimental research

Institute of Scientific and Technical Information of China (English)

Jin-hui Luo; Di-fang Wan; Yang Yang; Guang Yang

2011-01-01

Purpose-The purpose of this paper is to empirically analyze the role of differentiated margin system in leading investors' investing behavior and then optimize investor structure in futures markets.Design/methodology/approach-Using economic experimental research method,this paper designs and conducts a futures market experiment according to experimental research's basic norms,thus acquiring needed and credible empirical data.Findings-By analyzing the experimental data,it is found that compared with situations in futures markets that implement uniform margin system,investors' (especially speculators') futures open position and the ratio of their open position and futures turnover are both significantly higher,in futures markets that implement differentiated margin system.On the other hand,differentiated margin system has no effects on hedgers' futures turnover,but significantly reduces speculators' futures turnover.Research limitations/implications-The findings suggest that compared with uniform margin system,differentiated margin system is beneficial to effectively restrict both speculators' and hedgers' speculating behavior and lead hedgers' market participation.Practical implications-In order to resolve the problem of unreasonable investor structure in China's futures market,i.e.lack of hedgers and over-speculating China's futures market's regulators should reform the margin system and adopt differentiated margin system to lead investors' rational behavior and optimize investor structure.Originality/value-This paper empirically analyzes and verifies,for the first time,the roles of differentiated margin system in affecting investors' investing behavior.The futures market experiment designed and used in this study is a pioneering and exploratory experiment.

Developing tools to identify marginal lands and assess their potential for bioenergy production

Science.gov (United States)

Galatsidas, Spyridon; Gounaris, Nikolaos; Dimitriadis, Elias; Rettenmaier, Nils; Schmidt, Tobias; Vlachaki, Despoina

2017-04-01

The term "marginal land" is currently intertwined in discussions about bioenergy although its definition is neither specific nor firm. The uncertainty arising from marginal land classification and quantification is one of the major constraining factors for its potential use. The clarification of political aims, i.e. "what should be supported?" is also an important constraining factor. Many approaches have been developed to identify marginal lands, based on various definitions according to the management goals. Concerns have been frequently raised regarding the impacts of marginal land use on environment, ecosystem services and sustainability. Current tools of soil quality and land potentials assessment fail to meet the needs of marginal land identification and exploitation for biomass production, due to the lack of comprehensive analysis of interrelated land functions and their quantitative evaluation. Land marginality is determined by dynamic characteristics in many cases and may therefore constitute a transitional state, which requires reassessment in due time. Also, marginal land should not be considered simply a dormant natural resource waiting to be used, since it may already provide multiple benefits and services to society relating to wildlife, biodiversity, carbon sequestration, etc. The consequences of cultivating such lands need to be fully addressed to present a balanced view of their sustainable potential for bioenergy. This framework is the basis for the development of the SEEMLA tools, which aim at supporting the identification, assessment, management of marginal lands in Europe and the decision-making for sustainable biomass production of them using appropriate bioenergy crops. The tools comprise two applications, a web-based one (independent of spatial data) and a GIS-based application (land regionalization on the basis of spatial data), which both incorporate: - Land resource characteristics, restricting the cultivation of agricultural crops but

Hepatocellular carcinoma with marginal superparamagnetic iron oxide uptake on T2*-weighted magnetic resonance imaging: Histopathologic correlation

International Nuclear Information System (INIS)

Ishigami, Kousei; Tajima, Tsuyoshi; Fujita, Nobuhiro; Nishie, Akihiro; Asayama, Yoshiki; Kakihara, Daisuke; Nakayama, Tomohiro; Okamoto, Daisuke; Taketomi, Akinobu; Shirabe, Ken; Honda, Hiroshi

2011-01-01

Purpose: To evaluate the characteristics of hepatocellular carcinomas (HCCs) with marginal superparamagnetic iron oxide (SPIO) uptake on T2*-weighted MRI. Materials and methods: The study group consisted of 73 patients with 83 surgically resected HCCs. Preoperative SPIO-enhanced MRI studies were retrospectively reviewed. Marginal SPIO uptake was considered positive if a rim-like or band-like low intensity area was present on SPIO-enhanced T2*-weighted images. The prevalence of marginal SPIO uptake was evaluated. Pathological specimens with hematoxylin and eosin staining and immunohistochemical staining of CD68 were reviewed in HCCs with marginal SPIO uptake and 33 HCCs without marginal SPIO uptake (control group). Results: Ten of 83 (12%) HCCs showed marginal SPIO uptake. All HCCs were hypervascular, and only one nodule showed a nodule-in-nodule appearance on imaging findings. The pathology specimens suggested possible causes of marginal SPIO uptake, including marginal macrophage infiltration in moderately or poorly differentiated HCC (n = 4), residual normal hepatic tissue at the marginal area of confluent multinodular or single nodular with extranodular growth type HCC (n = 3), and a well-differentiated HCC component in nodule-in-nodule type HCC (n = 3). Marginal macrophage infiltration was not seen in the control group. Conclusion: SPIO-enhanced MRI may be able to demonstrate marginal macrophage infiltration in HCC.

Margins related to equipment design

International Nuclear Information System (INIS)

Devos, J.

1994-01-01

Safety margins related to design of reactor equipment are defined according to safety regulations. Advanced best estimate methods are proposed including some examples which were computed and compared to experimental results. Best estimate methods require greater computation effort and more material data but give better variable accuracy and need careful experimental validation. Simplified methods compared to the previous are less sensitive to material data, sometimes are more accurate but very long to elaborate

The Deafening Silence: Discussing Children's Drawings for Understanding and Addressing Marginalization

Science.gov (United States)

Angelides, Panayiotis; Michaelidou, Antonia

2009-01-01

Researchers who deal with inclusive education have made great efforts to listen to the voices of children in order to understand marginalization. Despite the fact that these efforts take place, the voices of many children fail to be heard and hence many children continue to be marginalized. In this article we will develop and implement a technique…

A margin model to account for respiration-induced tumour motion and its variability

International Nuclear Information System (INIS)

Coolens, Catherine; Webb, Steve; Evans, Phil M; Shirato, H; Nishioka, K

2008-01-01

In order to reduce the sensitivity of radiotherapy treatments to organ motion, compensation methods are being investigated such as gating of treatment delivery, tracking of tumour position, 4D scanning and planning of the treatment, etc. An outstanding problem that would occur with all these methods is the assumption that breathing motion is reproducible throughout the planning and delivery process of treatment. This is obviously not a realistic assumption and is one that will introduce errors. A dynamic internal margin model (DIM) is presented that is designed to follow the tumour trajectory and account for the variability in respiratory motion. The model statistically describes the variation of the breathing cycle over time, i.e. the uncertainty in motion amplitude and phase reproducibility, in a polar coordinate system from which margins can be derived. This allows accounting for an additional gating window parameter for gated treatment delivery as well as minimizing the area of normal tissue irradiated. The model was illustrated with abdominal motion for a patient with liver cancer and tested with internal 3D lung tumour trajectories. The results confirm that the respiratory phases around exhale are most reproducible and have the smallest variation in motion amplitude and phase (approximately 2 mm). More importantly, the margin area covering normal tissue is significantly reduced by using trajectory-specific margins (as opposed to conventional margins) as the angular component is by far the largest contributor to the margin area. The statistical approach to margin calculation, in addition, offers the possibility for advanced online verification and updating of breathing variation as more data become available

Observations at convergent margins concerning sediment subduction, subduction erosion, and the growth of continental crust

Science.gov (United States)

von Huene, Roland E.; Scholl, D. W.

1991-01-01

At ocean margins where two plates converge, the oceanic plate sinks or is subducted beneath an upper one topped by a layer of terrestrial crust. This crust is constructed of continental or island arc material. The subduction process either builds juvenile masses of terrestrial crust through arc volcanism or new areas of crust through the piling up of accretionary masses (prisms) of sedimentary deposits and fragments of thicker crustal bodies scraped off the subducting lower plate. At convergent margins, terrestrial material can also bypass the accretionary prism as a result of sediment subduction, and terrestrial matter can be removed from the upper plate by processes of subduction erosion. Sediment subduction occurs where sediment remains attached to the subducting oceanic plate and underthrusts the seaward position of the upper plate's resistive buttress (backstop) of consolidated sediment and rock. Sediment subduction occurs at two types of convergent margins: type 1 margins where accretionary prisms form and type 2 margins where little net accretion takes place. At type 2 margins (???19,000 km in global length), effectively all incoming sediment is subducted beneath the massif of basement or framework rocks forming the landward trench slope. At accreting or type 1 margins, sediment subduction begins at the seaward position of an active buttress of consolidated accretionary material that accumulated in front of a starting or core buttress of framework rocks. Where small-to-mediumsized prisms have formed (???16,300 km), approximately 20% of the incoming sediment is skimmed off a detachment surface or decollement and frontally accreted to the active buttress. The remaining 80% subducts beneath the buttress and may either underplate older parts of the frontal body or bypass the prism entirely and underthrust the leading edge of the margin's rock framework. At margins bordered by large prisms (???8,200 km), roughly 70% of the incoming trench floor section is

An approximate marginal logistic distribution for the analysis of longitudinal ordinal data

NARCIS (Netherlands)

Nooraee, Nazanin; Abegaz, Fentaw; Ormel, Johan; Wit, Ernst; van den Heuvel, Edwin R

Subject-specific and marginal models have been developed for the analysis of longitudinal ordinal data. Subject-specific models often lack a population-average interpretation of the model parameters due to the conditional formulation of random intercepts and slopes. Marginal models frequently lack

Lead poisoning and marginalization in newborns of Morelos, Mexico

Directory of Open Access Journals (Sweden)

Martha María Téllez-Rojo

2017-05-01

Full Text Available Objective. To determine the prevalence of lead (Pb poi- soning at birth in Morelos, analyze its distribution by social marginalization level, and estimate the association with the use of lead glazed ceramics (LGC. Materials and methods. Blood lead level (BLL in umbilical cord was measured in a representative sample of 300 randomly selected births at the Morelos Health Services and state IMSS. Results. The prevalence of Pb poisoning at birth (BLL> 5µg/dL was 14.7%(95%CI: 11.1, 19.3 and 22.2% (95%CI: 14.4, 32.5 in the most socially marginalized municipalities. 57.1% (95%CI: 51.3, 62.7of the mothers used LGC during pregnancy, and the frequency of use was significantly associated with BLL. Conclusion. This is the first study to document the proportion of new- borns with Pb poisoning who are at risk of experiencing the related adverse effects. It is recommended to monitor BLL at birth and take action to reduce this exposure, especially in socially marginalized populations.

The effect of porcelain firing and type of finish line on the marginal fit of zirconia copings.

Science.gov (United States)

Vojdani, Mahroo; Safari, Anahita; Mohaghegh, Mina; Pardis, Soheil; Mahdavi, Farideh

2015-06-01

Although all-ceramic restorations are broadly used, there is a lack of information concerning how their fit is affected by fabrication procedure and marginal configuration. The purpose of this study was to evaluate the marginal fit of zirconia CAD/CAM ceramic crowns before and after porcelain firing. The influence of finish line configuration on the marginal fit was also evaluated. Twenty standardized zirconia CAD/CAM copings were fabricated for chamfer and shoulder finish line designs (n=10). The marginal fit of specimens was measured on 18 points, marked on the master metal die by using a digital microscope. After the crowns were finalized by porcelain veneering, the measurements of marginal fit were performed again. The means and standard deviations were calculated and data were analyzed using student's t-test and paired t-test (α=0.05). There were significant differences between marginal fit of chamfer and shoulder finish line groups before and after porcelain firing (p= 0.014 and p= 0.000, respectively). The marginal gap of copings with shoulder finish line was significantly smaller than those with chamfer configuration (p= 0.000), but there were no significant differences between the two marginal designs, after porcelain firing (p= 0.341). Porcelain veneering was found to have a statistically significant influence on the marginal fit of zirconia CAD/CAM crowns. Both margin configurations showed marginal gaps that were within a reported clinically acceptable range of marginal discrepancy.

Correspondence between conventional and digitised radiographs for assessment of marginal bone.

Science.gov (United States)

Bahrami, Golnosh; Isidor, Flemming; Wenzel, Ann; Vaeth, Michael

2013-01-01

To compare reproducibility of marginal bone measurements in conventional film and digitised radiographs and to assess whether variations in reproducibility occurred in measurements taken in a longitudinal, epidemiological survey. Triplicate measurements of the marginal bone level and of remaining bone were obtained from film and digitised full-mouth radiographic surveys from 20 individuals who were examined three times at five-year intervals in a longitudinal study design. The digitalisation of the films was conducted by scanning the film with a flatbed scanner. The standard deviation (SD) of the triplicate measurements served as the statistic for reproducibility. The time spent for recording one radiographic survey, which consisted of 14 periapicals and 2 bitewings, was documented. Statistically significant differences existed in the reproducibility of marginal bone level measurements obtained at the first examination and the two subsequent examinations both for film and digitised radiographs (P < 0.05). The difference in marginal bone level measurements (film vs digitised) was 0.16 mm (SD = 0.45 mm). Similarly, the overall difference in measurements of the remaining bone was 0.12 mm (SD = 0.61 mm). Recording of a digitised survey lasted on average 5 min (SD = 1.5 min), while the recording of a film survey lasted on average 14 min (SD = 1 min). Digitising film is an acceptable method for the purpose of assessing the marginal bone level and will save time in longitudinal, epidemiological studies.

Treatment of Passive Component Reliability in Risk-Informed Safety Margin Characterization FY 2010 Report

Energy Technology Data Exchange (ETDEWEB)

Robert W Youngblood

2010-09-01

The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy (DOE) Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). A technical challenge at the core of this effort is to establish the conceptual and technical feasibility of analyzing safety margin in a risk-informed way, which, unlike conventionally defined deterministic margin analysis, is founded on probabilistic characterizations of SSC performance.

Glacier-influenced sedimentation on high-latitude continental margins

National Research Council Canada - National Science Library

Dowdeswell, J. A; Cofaigh, C. Ó

2002-01-01

This book examines the process and patterns of glacier-influenced sedimentation on high-latitude continental margins and the geophysical and geological signatures of the resulting sediments and landform...

Brote de bacteriemia por Serratia marcescens en pacientes portadores de catéteres tunelizados en hemodiálisis secundario a colonización de la solución antiséptica. Experiencia en 4 centros

Directory of Open Access Journals (Sweden)

José L. Merino

2016-11-01

Conclusiones: Las bacteriemias por gérmenes no convencionales deben ponernos sobre aviso para investigar posibles brotes. La aplicación de una solución contaminada por S. marcescens en los catéteres en hemodiálisis fue la vía de bacteriemia. El tratamiento antibiótico intravenoso y el sellado de los catéteres permitió una excelente supervivencia tanto de los pacientes como de los catéteres.

Marginal adaptation of CAD-CAM onlays: Influence of preparation design and impression technique.

Science.gov (United States)

Lima, Fernanda Ferruzzi; Neto, Constantino Fernandes; Rubo, José H; Santos, Gildo Coelho; Moraes Coelho Santos, Maria Jacinta

2018-03-15

Factors that may affect the marginal adaptation of computer-aided design and computer-aided manufacturing (CAD-CAM) restorations include preparation design, impression technique, and CAD-CAM system. The influence of impression technique and preparation design on CAD-CAM partial coverage restorations has not been fully addressed. The purpose of this in vitro study was to investigate the influence of direct and indirect digital impression techniques and 2 preparation designs on the marginal adaptation of CAD-CAM onlays. Two mesio-occlusal buccal onlay preparations with reduction of the mesiobuccal cusp were made: conventional preparation (CP) with a 1.2-mm modified shoulder margin and modified preparation (MP) flat cuspal reduction without shoulder. Virtual models were generated from each preparation by using a digital scanner (BlueCam; Dentsply Sirona) from the plastic teeth (direct digital impression) or from the stone dies (indirect digital impression). Onlays were designed using a CAD-CAM system (CEREC 4.0; Dentsply Sirona), and nanoceramic resin blocks (Lava Ultimate Restorative; 3M ESPE) were milled using the CEREC MCX milling machine. Marginal discrepancy was evaluated using an optical stereomicroscope at ×25 magnification in 18 locations distributed along the margins of the preparation. The data were analyzed by using 3-way ANOVA followed by the Tukey HSD test (α=.05). CP presented a statistically significant reduced average marginal adaptation (59 ±50 μm) than did MP (69 ±58 μm) (Pmarginal discrepancy in the mesial and buccal locations of MP when compared with CP. Regarding impression techniques, the buccal location presented the smallest average marginal discrepancy in restorations fabricated with indirect impression when compared with direct impression (42 ±33 μm and 60 ±39 μm) (Pmargin presented improved marginal adaptation compared with modified preparation with flat cuspal reduction. Direct and indirect digital impression techniques produced

Clinical study of the marginal microfiltration in restorations with amalgam applying sealant cavitario

OpenAIRE

Lahoud Salem, Víctor; Mendoza Zapata, Janet; Vidal Goñi, Raúl

2014-01-01

The present study to evaluate the clinical evaluation, marginal leakage of 30 amalgams restorations with sealers cavity and 30 amalgams restorations not sealers cavity. After of 12 months observation in amalgams restorations with sealers cavity 100% success in marginal leakage and not presents of secondary caries, not to have presents clinical cases of sensitivity post-operative and pulp inflammation. El presente estudio consistió en evaluar clínicamente la microfiltración marginal en 30 r...

Marginal abatement cost curves for NOx incorporating both controls and alternative measures

Science.gov (United States)

A marginal abatement cost curve (MACC) traces out the efficient marginal abatement cost level for any aggregate emissions target when a least cost approach is implemented. In order for it to represent the efficient MAC level, all abatement opportunities across all sectors and loc...

Parent-Child Cultural Marginalization and Depressive Symptoms in Asian American Family Members

Science.gov (United States)

Kim, Su Yeong; Gonzales, Nancy A.; Stroh, Kunise; Wang, Jenny Jiun-Ling

2006-01-01

The current study findings refute the recent claim that marginality theory lacks construct validity. Cultural marginalization is significantly related to depressive symptoms in Korean American, Chinese American, and Japanese American parents and adolescents living in the United States. Correlational analyses indicate that adolescents' depressive…

Sedimentation on continental margins: An integrated program for innovative studies during the 1990s

Science.gov (United States)

Nittrourer, Charles A.; Coleman, James M.; Rouge, Baton; Flood, Roger D.; Ginsburg, Robert N.; Gorsline, Donn S.; Hine, Albert C.; Sternberg, Richard W.; Swift, Donald J. P.; Wright, L. Donelson

Continental margins are of great scientific interest, and they represent the focus of human interaction with the ocean. Their deep structure forms the transition from continental to oceanic crust, and their surface expression extends from coastal environments of estuaries and shorelines across the continental shelf and slope to either the base of a continental rise or a marginal trough. Modern continental margins represent natural laboratories for investigation of complex relationships between physical, chemical, and biological phenomena, which are sensitive to environmental conditions both on the land and in the ocean. The history of these conditions is preserved within the sedimentary deposits of continental margins. The deposits form repositories for much of the particulate material transported off the world's land masses and produced from dissolved components in the world ocean. Past deposits of continental margins have been uplifted to form many mountain ranges and sedimentary terrains of the world, which record details of Earth history and contain valuable natural resources, such as petroleum and natural gas. Modern deposits of continental margins record the more recent events that have influenced Earth and also contain natural resources (for instance, minerals, sand, and gravel), as well as anthropogenic pollutants (for example, heavy metals and pesticides). The fates of many materials beneficial and deleterious to humans are dependent on the pathways followed by sedimentary particles on continental margins.