bluuebunny/crossref_metadata_2025 huggingface dataset:
Hemodialysis Membrane Coated with a Polymer Having a Hydrophilic Blood-Contacting Layer can Enhance Diffusional Performance
Authors: Tagaya Masashi , Nagoshi Saki , Matsuda Morihiro , Takahashi Shunsuke , Okano Shinya , Hara Kazunobu
Published: August 2017

Purpose

Currently, the foreign surfaces of various extracorporeal circulation devices are coated with a biocompatible polymer coating agent (BPA), which creates a hydrophilic blood-contacting layer to reduce thrombogenicity, while the membranes in hemodialyzers are not. We aimed to clarify other side effects of BPA-coated membranes by examining the diffusion performance in in vitro experiments.

Methods

We used a polyethersulfone membrane (sieving coefficient of albumin is ≤0.01) coated with BPA product, SEC-1™ (Toyobo), in a hemodialyzer. To estimate the diffusion rates of a wide range of molecules, 2 L of saline containing vancomycin, lysozyme, and albumin were recirculated in the circuit configured with a hemodialyzer, and dialyzed continuously using water. The concentrations of sodium, vancomycin, lysozyme, and albumin were measured every 5 minutes for 30 minutes and compared in experiments with BPA-coated (n = 4) and BPA-noncoated (n = 4) membranes.

Results

The removal rates of sodium and vancomycin after 5 minutes of dialysis (n = 24) were significantly higher in BPA-coated than noncoated membranes, while those of lysozyme and albumin were not significantly different. The removal rates of sodium and vancomycin after 30 minutes of dialysis (n = 4) were significantly higher, and those of lysozyme were significantly lower in BPA-coated than noncoated membranes, while those of albumin were not significantly different.

Conclusions

The preliminary study suggests that BPA-coated membranes enhanced the diffusion rate of molecules with low and middle molecular weight without affecting the sieving coefficient of albumin. Thus, BPA coating can enhance the dialysis performance of membranes.
The Impact on Ovarian Reserve of CO2 Laser Fiber Vaporization in the Treatment of Ovarian Endometrioma: A Prospective Clinical Trial
Authors: Ottolina Jessica , Castellano Laura M. , Ferrari Stefano , Tandoi lacopo , Candotti Giorgio , De Stefano Francesca , Bartiromo Ludovica , Candiani Massimo
Published: August 2017

Background

In recent years, excisional surgery has been questioned as an ideal surgical approach for endometriomas because it is associated with potential removal of healthy ovarian tissue and loss of ovarian follicles with subsequent reduction of ovarian reserve. The aim of our study was to evaluate the benefits of CO2 laser vaporization through a clinical trial assessing the postoperative changes in ovarian reserve as indicated by antral follicle count (AFC) and anti-Müllerian hormone (AMH).

Materials and Methods

Fifteen patients undergoing surgery for primary unilateral or bilateral symptomatic endometriomas were enrolled in the study. During surgery, the cystic lining was completely vaporized with CO2 laser fiber (AcuPulse Duo system, Lumenis); before surgery and at 1 and 3 months after surgery, ovarian reserve was evaluated by pelvic ultrasound to determine the AFC, and blood sample to determine AMH levels.

Results

The AFC of the operated ovary was significantly increased after treatment at 1 and 3 months' follow-up (p = 0.0021; p = 0.005, respectively); the increase is particularly significant in women younger than 35 years (p = 0.012). No statistically significant changes were reported in serum AMH concentrations at 1 or 3 months' follow-up. No recurrences of symptoms and no recurrences of endometrioma were reported.

Conclusions

These data support the hypothesis that endometrioma vaporization with CO2 laser fiber may be a valid method to preserve ovarian function; however, further studies are required before advocating the routine use of CO2 laser vaporization for the management of ovarian endometriosis.
Thrombosis of the Superior Vena Cava Due to a Hickman Catheter: Successful Management by rt-PA Thrombolysis
Authors: Zaccone Giuseppe , Pafundi Paolo D. , Veneziani Augusto , Verbo Alessandro , Colli Rosa
Published: August 2017

Introduction

Venous thrombosis is a frequent complication of long-term venous access. Its management is well defined in most cases, but some specific clinical situations have not yet been definitively standardized. Thrombosis may occur at the catheter tip and involve the superior vena cava (SVC) and/or the right atrium (RA). In such cases, while the need for a rapid intervention to relieve the venous obstruction and avoid embolism is obvious, the best management is still to be established.

Case description

We report the case of a 25-year-old woman with symptomatic thrombosis of SVC and RA, associated with a Hickman catheter, which was successfully treated by recombinant tissue plasminogen activator (rt-PA).

Conclusions

According to the literature, thrombolytic therapy with rt-PA may be considered the treatment of choice in symptomatic thrombosis of SVC secondary to long-term catheter, uncertainty still exists about dosage, optimal rate of infusion, and optimal duration of treatment, as well as the criteria for choosing local versus systemic infusion.
Anachronism in Recent Moral Philosophy
Authors: Whistler Daniel
Published: August 2017

In this article, I analyze the debate between Raimond Gaita and Christopher Hamilton on the rhetorical practices appropriate to achieving lucidity (full attention to moral reality). I concentrate on the deployment of untimely terms (taking “soul” as my central example) as a means by which both Gaita and Hamilton attempt to provoke lucidity in the reader. In the final sections of the article, I use this case study of the moral term “soul” to set out a theoretical model for the process of becoming lucid in order to (partially) defend Gaita's philosophical style against Hamilton's criticisms. At stake is the possibility of other forms of rigor, other forms of clarity, and other forms of cogency than analytic philosophizing typically presumes.
Explorando a gestão de contratos com fornecedores no contexto de CMMI-DEV e metodologias ágeis: a identificação de um gap
Authors: Santos Melquizedequi Cabral dos , Soares Elisiane Monteiro , Oliveira Sandro Ronaldo Bezerra , Vasconcelos Alexandre Marcos Lins de
Published: August 2017

A subcontratação de software é um processo de aquisição que significa delegar, por meio de contrato, o desenvolvimento de parte, ou totalidade do produto junto a fornecedores externos ao projeto. Vários estudos obtiveram sucesso com o uso da subcontratação nesse contexto. No entanto, as organizações continuam com problemas no planejamento, execução e gestão dos fornecedores dentro do processo de aquisição no desenvolvimento de software. Este estudo conduziu uma revisão sistemática da literatura com o intuito de explorar o atual estado da investigação sobre a relação entre Metodologias Ágeis e CMMI-DEV, no contexto da gestão do acordo de fornecedores. A revisão revelou a escassez de dados empíricos sobre a temática, apontando a necessidade de mais pesquisas sobre a combinação dessas abordagens.
Avaliação de maturidade de processos de gestão de riscos de TI: ferramenta de apoio para a qualidade e eficiência do processo
Authors: Araujo Misael Sousa de , Oliveira Edgard Costa , Monteiro Simone Borges Simão
Published: August 2017

A tecnologia da informação possui papel fundamental nas organizações, figurando como um componente estratégico para seus processos de negócio. A aplicação da gestão de riscos no contexto da governança de TI é fator crítico de sucesso para o alcance dos objetivos estratégicos das organizações. No entanto, apenas adotar práticas de gestão de riscos não é suficiente para garantir que sua aplicação trará os resultados esperados. Cada vez mais as organizações têm buscado conhecer quão eficientes tem sido seus processos, incluindo o processo de gestão de riscos, de forma a conhecer seu grau de eficiência em uma determinada escala, conhecer suas deficiências, e assim traçar planos para melhoria de seus processos e ainda comparar seu desempenho em relação a organizações similares. Dado à diversidade de modelos de maturidade e suas características, este artigo realizou um estudo comparativo entre os principais modelos de maturidade do mercado, selecionou um modelo aplicado à gestão de riscos de tecnologia da informação (escolhida via técnica de decisão multicritério Analytic Hierarchy Process – AHP) e propôs um instrumento de avaliação de maturidade em gestão de riscos de TI que possa ser utilizado por qualquer organização.
Técnicas de reconhecimento de padrões para identificação de ataque de DNS
Authors: Carvalho Henrique Carlos Fonte Boa , Pelli Eduardo
Published: August 2017

A maioria dos dispositivos conectados à Internet usufrui dos serviços de DNS (Domain Name System) para resolução de nomes de domínios. A partir da afirmação de que a maioria das redes não restringe o tráfego de pacotes destinados aos serviços de DNS, técnicas de ataques podem ser aplicadas, fazendo com que uma simples requisição de resolução de nome aparentemente normal, possa ocasionar um ataque causando diversos transtornos às vítimas. Os ataques do tipo Spoofing consistem em enganar o dispositivo do usuário, fazendo com que o computador identifique o dispositivo do usuário malicioso, de maneira confiável. Por se tratar de um tipo de ataque de alta periculosidade, devido à inexistência de pesquisas e técnicas eficientes na sua identificação, procura-se encontrar soluções viáveis para detecção deste tipo de ataque. Este trabalho teve como objetivo a aplicação de técnicas de Reconhecimento de Padrões através da aplicação das técnicas de Seleção de Características e Classificação de características para detecção de DNS Spoofing em redes locais de computadores. Foram obtidos resultados com acurácia média de 98,33% +- 0,64% na detecção na classe de falha da rede, ou seja, quando essas estavam sob ataque de DNS Spoofing.
Lori’s Help: um aplicativo para auxílio na alfabetização de pessoas com Síndrome de Down
Authors: Sousa Marcus Vinicius Girolneto , Ramos Dione , Castro Lays Xavier de , Cruz Michelle , Hannum Juliana Santos de Souza , Barbosa Talles Marcelo G. de A.
Published: August 2017

síndrome de Down é causada pela presença de três cromossomos 21 em todas ou na maior parte das células de um indivíduo [1]. As pessoas com síndrome de Down, ou trissomia do cromossomo 21, têm 47 cromossomos em vez de 46, como a maior parte da população. A pessoa com síndrome de Down tem idade cronológica diferente de idade funcional, desta forma, não é esperada uma resposta idêntica à resposta das pessoas com desenvolvimento típico [9]. Esta deficiência advém de desajustes funcionais do sistema nervoso, causando dificuldade no aprendizado. Essas dificuldades podem ser manifestadas desde a alfabetização básica até a realização de atividades cotidianas. O software desenvolvido neste trabalho tem o intuito de auxiliar pessoas com síndrome de Down durante o processo de alfabetização. O auxílio é fornecido por meio de atividades, como, por exemplo, o pareamento de vogais. Além disso, durante a execução dessas atividades, um algoritmo para biofeedback, conhecido como Attention Meter, monitora a atenção demonstrada pelos os usuários. Ao final, é gerado um relatório do desempenho para cada usuário, com marcadores que destacam o comportamento durante a execução de cada atividade. Assim, ao longo do processo de alfabetização, é possível quantificar e qualificar as atividades propostas não apenas pela quantidade de acertos, mas, também, pelo engajamento pessoal de cada usuário do aplicativo.
A Comparative Study of Faculty Members’ Career Advancement (Promotion) Systems in the United States and the Islamic Republic of Iran: Case Analysis of the University of Tehran and Portland State University
Authors: Tanaomi Mohammad Mehdi , Asaadi Robert Reza
Published: August 2017

This article examines the similarities and differences in the systems for faculty career advancement in higher education institutions in the United States and the Islamic Republic of Iran. The analysis focuses on two specific cases: the University of Tehran and Portland State University. Through this paired comparison, we draw out the similarities between the two cases. Both cases are public universities and share similar criteria pertaining to productivity in research, teaching, and community outreach/service as central aspects in their respective faculty evaluation guidelines. On the other hand, we find significant differences in terms of the following parameters: the degree of centralization in the decision-making process regarding promotion and tenure, specific guidelines pertaining to the adherence to Islamic ideology in the Iranian case, which lack a comparative equivalent in the American case, institutional mechanisms for faculty representation, and the ratio of tenure-track to non-tenure track faculty. The purpose of this article is to improve universities faculty members’ career advancement (promotion) systems through the identification of effective practices in an effort to develop better models of higher education.
O compartilhamento do conhecimento e a inovação nos relacionamentos interorganizacionais do tipo terceirização de tecnologia da informação
Authors: Faoro Roberta Rodrigues , Oliveira Mírian , Abreu Marcelo Faoro de
Published: August 2017

Introdução: este artigo apresenta uma análise do compartilhamento do conhecimento e da inovação nos relacionamentos interorganizacionais do tipo terceirização de Tecnologia da Informação.Objetivo: analisar a existência de relação entre o compartilhamento do conhecimento e a inovação nas relações interorganizacionais do tipo terceirização de tecnologia da informação (TI).Metodologia: pesquisa é exploratória, de natureza qualitativa e utilizando como estratégia o estudo de casos múltiplos, onde foram analisadas 12 empresas em ambientes de terceirização de TI, sendo 4 empresas fornecedoras de TI e 8 empresas clientes de TI. Os dados foram coletados através de entrevistas semiestruturadas, documentos e observação direta.Resultados: pode-se destacar que o compartilhamento do conhecimento mostrou contribuir para a existência de inovação no ambiente de terceirização de TI. As empresas fornecedoras priorizam a codificação do conhecimento compartilhado, enquanto que as clientes preferem o compartilhamento de conhecimento através de conversas informais. Identificou-se que os motivos para a terceirização de TI podem estar relacionados com o compartilhamento do conhecimento e a inovação.Conclusões: esta pesquisa contribui para o avanço do conhecimento acerca dos fenômenos compartilhamento de conhecimento e inovação em ambientes de terceirização da TI.
Arquitetura da informação para uma economia da informação
Authors: Cartaxo Mac Amaral , Basílio Flávio Augusto Corrêa , Duque Claudio Gottschalg
Published: August 2017

Introdução: A informação é entendida como a matéria-prima básica, da qual dependem os processos sejam para decisão ou aprendizado no âmbito organizacional. Deste modo a informação ao invés de constituir um pressuposto primário sobre a economia é, na verdade, mais do que isso, na medida em que ela é desejada como qualquer outro bem pelos agentes econômicos.Objetivo: O objetivo deste estudo foi identificar indícios da natureza conceitual sobre a heterogeneidade de informação como um fenômeno importante que produz impactos significativos sobre o equilíbrio de mercado e sobre o bem-estar dos agentes econômicosMetodologia: A pesquisa caracteriza-se como revisão de literatura nos campos da Ciência da Informação, especificamente no que tange a Arquitetura da Informação, contrastando com a Economia visando estabelecer um paralelo a respeito da chamada economia da informação. Resultados: Os principais resultados indicam que possuir uma Arquitetura da Informação que viabilize a ostensividade da informação, possibilita o fácil acesso ao conhecimento buscado por quem demanda, seja em função de sua clareza, conectividade, conteúdo contextualizado ao nível de conhecimento dos usuários, permitindo às organizações maximizar a eficiência das decisões.Conclusão: No que diz respeito ao uso de uma Arquitetura da Informação no âmbito de uma economia da informação, percebe-se que os consumidores aumentam o nível de utilidade na medida em que a informação traduzida de forma barata, clara e acessível em conhecimento reduz o grau de dispersão e de volatilidade dos preços.
MAIA - Método de Arquitetura da Informação Aplicada
Authors: Costa Ismael De Moura , Lima-Marques Mamede
Published: August 2017

Proposta de um constructo metodológico para o tratamento da informação em contextos complexos, distinguindo espaços de informação e revelando configurações inerentes a esses espaços. A argumentação é elaborada a partir de uma pesquisa teórica, de caráter analítico, empregando a distinção como forma de expressão de conceitos. A fenomenologia é empregada como posição filosófica que considera a correlação entre Sujeito ? Objeto. A pesquisa considera a noção de interpretação como um elemento integrante na definição de conceitos. Com base nesses postulados, são formulados os passos para transformar um espaço de informação. Este artigo explora a forma como o método é estruturado para tratar informações em seu contexto a partir de uma sucessão de ciclos evolutivos divididos em momentos, que, por sua vez, evoluem em atos de transformação. Os atos de transformação são regidos por critérios de realização. Os métodos são ordenados e orientados por princípios fenomenológicos, gerando estados úteis de configuração de um espaço de informação. São apresentadas possíveis aplicações como um método científico, como ferramenta de configuração em espaços de informação e como um gerador de ontologias. Há ainda um breve apanhado das análises dos pesquisadores que já avaliaram o método nos três aspectos de aplicação destacados.
Victimization and Perpetration of Intimate Partner Violence among Female and Male Youth and Adults in South Africa
Authors: Peltzer Karl , Phaswana-Mafuya Nancy , Pengpid Supa
Published: August 2017

OBJECTIVE: Intimate partner violence (IPV) is a huge public health problem. The aim of the study was to estimate the prevalence and influence of sociodemographic and health characteristics on IPV victimization and perpetration among women and men 15 years and older in South Africa.MATERIALS & METHODS: Data based on the South African national population-based survey in 2012 for 15916 (8532 women and 7384 men) aged 15 years and older who were in an intimate partner relationship were analysed. Bivariate and multivariable logistic regression was conducted to assess the association between sociodemographic factors, health variables and IPV victimization and perpetration.RESULTS: Among women, 8.5% had experienced any form of IPV in the past 12 months, and 3.5% of the women had engaged in IPV perpetration in the past 12 months. Among men, 5.0% had experienced any form of IPV in past 12 months, and 4.4% of the men had engaged in IPV perpetration in the past 12 months. In multivariable logistic regression analysis among women, younger age, being African Black, having psychological distress, having been a victim of violent crime and having had multiple sexual partners were associated with IPV victimization in the past 12 months, while younger age, psychological distress, hazardous or harmful alcohol use, and having had multiple sexual partners was associated with IPV perpetration in the past 12 months. In multivariable logistic regression analysis among men, younger age, psychological distress, hazardous or harmful alcohol use, and having been a victim of violence crime was associated with IPV victimization in the past 12 months, while younger age, poor health status, psychological distress, hazardous or harmful alcohol use, and illicit drug use was associated with IPV perpetration in the past 12 months.CONCLUSION: Past 12-month prevalence of IPV victimization and perpetration among women and men was significant. IPV gender commonalities and differences in risk factors, such as psychological distress, substance use, crime victimization and sexual risk behaviour, may inform strategies of violence prevention programmes.
Theory of Mind Training in Children with Autism: Relating the Shared Attention Mechanism to the Theory of Mind Mechanism vs. Understanding Beliefs Training
Authors: Bergstrand Othman Lama , Collet-Klingenberg Lana
Published: August 2017

The purpose of this training study was to examine two interventions that aim to improve the performance of students with Autism Spectrum Disorder (ASD) on False Belief Tasks (FBT) which examines the ability to recognize others’ mental representation of the world. The first intervention involved drawing connections between the Shared Attention Mechanism (SAM) and the Theory of Mind (ToMM) Mechanism. The second intervention taught belief understanding and the fact that a person’s beliefs about propositions may be false or true. To that end, we employed ABC and ACB multiple baselines across subject designs with matched controls. To assess generalization of learned skills, parents or teachers were interviewed. Results suggest that both interventions were effective.
Forestation in Puerto Rico, 1970s to Present
Authors: Yuan Fei , Lopez Jose Javier , Arnold Sabrina , Brand Anna , Klein Jonas , Schmidt Maureen , Moseman Erin , Michels-Boyce Madeline
Published: August 2017

It is important to monitor the trend of forestland changes, as forests are vital sources and sinks of carbon on the earth. One of the most densely populated jurisdictions of the United States, Puerto Rico, has experienced significant transformations in the past century. This study examines forestation in the main island of Puerto Rico during the past four decades using feature extraction and change detection analysis in multitemporal Landsat satellite imagery. The results of the study show that forest cover in Puerto Rico had almost tripled from 15.7% to 45.7% between 1972 and 2014. Moreover, the forestation trend and pace in abandoned coffee plantations and pastures continued after 1990, driven by continuous socioeconomic transformation. Natural forestation and conservation efforts from the government and nongovernment organizations have also contributed to the forest growth on the island. The information gained and lessons learned during the process may be applied to other densely populated tropical insular territories.
Biomassa arbórea e de sub-bosque e da serapilheira acumulada em povoamentos de Eucalyptus urophylla x Eucalyptus grandis
Authors: Salvador Simone Martini , Schumacher Mauro Valdir , Stahl James , Santos Joel Carvalho
Published: August 2017

O presente trabalho teve por objetivos quantificar a biomassa nos diferentes componentes das árvores, na serapilheira acumulada sobre o solo e no sub-bosque. Foi realizado com híbridos de Eucalyptus urophylla x Eucalyptus grandis, aos 7 anos de idade, em dois solos distintos no município de Telêmaco Borba – PR. O solo A (Cambissolo Háplico Tb Distrófico latossólico) caracterizado por apresentar textura arenosa e o solo B (Latossolo Vermelho Distroférrico típico) com textura argilosa. Delimitaram-se quatro parcelas, localizadas em cada solo, realizaram-se a medição de todos os diâmetros e escolha das árvores a serem abatidas. As árvores foram seccionadas ao nível do solo e fracionadas nos componentes: folhas, galhos, casca, madeira do tronco e raiz, coletaram-se uma amostra representativa de cada fração, bem como se realizaram a pesagem das mesmas, para determinação da biomassa. Para a análise da serapilheira acumulada foram coletadas 10 amostras em cada parcela com uma moldura de ferro de 30 cm x 30 cm. Toda a vegetação contida dentro da área útil de cada árvore abatida (7,5 m2) foi considerada como sub-bosque, onde se coletou toda a biomassa acima e abaixo do solo. A biomassa arbórea total do Eucalyptus urophylla x Eucalyptus grandis para o solo A e B foi de 257,99 e 301,20 Mg ha-1, respectivamente. A serapilheira acumulada sobre o solo foi superior no solo B, equivalendo a 16,62% maior em relação ao solo A. Já, o sub-bosque apresentou biomassa total de 1,08 Mg ha-1para o solo A, sendo esta 47,22% superior ao solo B. Conclui-se que a biomassa arbórea total do solo B é superior a biomassa arbórea total do solo A, porém os componentes da biomassa arbórea e serapilheira acumulada no solo A apresentaram uma redução, quando comparados com os componentes do solo B, exceto os componentes raiz e sub bosque os quais apresentaram biomassa total maior no solo A.
Diretrizes nacionais e o descompasso na formação humanística do curso de graduação em Administração Pública da UFRRJ
Authors: Baptista Vinicius Ferreira
Published: August 2017

Neste texto discute-se o projeto pedagógico do curso de graduação em Administração Pública da Universidade Federal Rural do Rio de Janeiro. Nos apoiamos em documentos oficiais da referida instituição e nas Diretrizes Curriculares Nacionais. Analisamos conteúdo do projeto e da matriz curricular, que propõe uma formação humanística. Entendemos que existe um descompasso da formação humanística do curso de graduação em Administração Pública da UFRRJ. Tal formação não é humanística por renegar elementos básicos de desigualdades sociais e não preparar devidamente o discente para análise crítica da realidade social. É uma formação mecânica, engessada e descompassada entre o plano teórico do projeto pedagógico e sua pedagogia em si, retratada na matriz e ementas das disciplinas que a compõe.Palavras-chave: projeto pedagógico, administração pública, formação humanística, UFRRJ.
Gestão de um núcleo de apoio ao estudante na universidade
Authors: Sales Filipe , Paixão Márcia
Published: August 2017

Este artigo é resultado de uma pesquisa de especialização em Gestão Educacional que foi realizada junto ao Ânima da UFSM. Buscou-se compreender qual era a percepção de gestão no Ânima a partir da equipe de profissionais com vistas a um espaço de atenção e cuidado aos estudantes do ensino superior. A metodologia baseou-se numa sessão reflexiva, com dois eixos centrais que acompanharam a conversa. Pela análise dos dados constatou-se que a equipe de profissionais compreende o que é gestão, como esta funciona, contudo não consegue identificar qual é o modelo norteador do Núcleo de Apoio do Estudante.Palavras-chave: gestão, equipe multiprofissional, ensino superior.
Os conceitos de gestão e administração: aplicação ao estudo das gestões dos diretores da Faculdade de Ciências Médicas da Universidade Estadual de Campinas
Authors: Amaral Ivan Luiz Martins Franco do , Nunes Everardo Duarte
Published: August 2017

Neste artigo se descreve a metodologia utilizada na elaboração de um projeto que analisa as gestões da Faculdade de Ciências Médicas da Universidade Estadual de Campinas, durante o período de 1963-2014. Parte-se da conceituação de gestão e administração e da caracterização das diferentes teorias de administração. A principal referência em termos de metodologia é a metodologia quadripolar - epistemológica, teórica, morfológica e técnica - elaborada por Bruyne, Herman e Schoutheete (1977). Para ilustrar essa abordagem teórica e metodológica é apresentada uma breve análise da primeira gestão (1963-1969). Concluiu-se que a metodologia é adequada e há possibilidade de aplicação ao estudo das gestões que se seguiram a primeira.Palavras-chave: gestão, administração, gestão institucional, escolas médicas, Faculdade de Ciências Médicas da Unicamp.
The importance of grain size to mantle dynamics and seismological observations
Authors: Dannberg J. , Eilon Z. , Faul Ulrich , Gassmöller Rene , Moulik Pritwiraj , Myhill Robert
Published: August 2017

Grain size plays a key role in controlling the mechanical properties of the Earth's mantle, affecting both long‐time‐scale flow patterns and anelasticity on the time scales of seismic wave propagation. However, dynamic models of Earth's convecting mantle usually implement flow laws with constant grain size, stress‐independent viscosity, and a limited treatment of changes in mineral assemblage. We study grain size evolution, its interplay with stress and strain rate in the convecting mantle, and its influence on seismic velocities and attenuation. Our geodynamic models include the simultaneous and competing effects of dynamic recrystallization resulting from dislocation creep, grain growth in multiphase assemblages, and recrystallization at phase transitions. They show that grain size evolution drastically affects the dynamics of mantle convection and the rheology of the mantle, leading to lateral viscosity variations of 6 orders of magnitude due to grain size alone, and controlling the shape of upwellings and downwellings. Using laboratory‐derived scaling relationships, we convert model output to seismologically observable parameters (velocity and attenuation) facilitating comparison to Earth structure. Reproducing the fundamental features of the Earth's attenuation profile requires reduced activation volume and relaxed shear moduli in the lower mantle compared to the upper mantle, in agreement with geodynamic constraints. Faster lower mantle grain growth yields best fit to seismic observations, consistent with our reexamination of high‐pressure grain growth parameters. We also show that ignoring grain size in interpretations of seismic anomalies may underestimate the Earth's true temperature variations.
First‐principles prediction of Si‐doped Fe carbide as one of the possible constituents of Earth's inner core
Authors: Das Tilak , Chatterjee Swastika , Ghosh Sujoy , Saha‐Dasgupta Tanusri
Published: August 2017

We perform a computational study based on first‐principles calculations to investigate the relative stability and elastic properties of the doped and undoped Fe carbide compounds at 200–364 GPa. We find that upon doping a few weight percent of Si impurities at the carbon sites in Fe7C3 carbide phases, the values of Poisson's ratio and density increase while VP, and VS decrease compared to their undoped counterparts. This leads to marked improvement in the agreement of seismic parameters such as P wave and S wave velocity, Poisson's ratio, and density with the Preliminary Reference Earth Model (PREM) data. The agreement with PREM data is found to be better for the orthorhombic phase of iron carbide (o‐Fe7C3) compared to hexagonal phase (h‐Fe7C3). Our theoretical analysis indicates that Fe carbide containing Si impurities can be a possible constituent of the Earth's inner core. Since the density of undoped Fe7C3 is low compared to that of inner core, as discussed in a recent theoretical study, our proposal of Si‐doped Fe7C3 can provide an alternative solution as an important component of the Earth's inner core.
New perspectives on volcano monitoring in a tropical environment: Continuous measurements of soil CO2 flux at Piton de la Fournaise (La Réunion Island, France)
Authors: Boudoire G. , Di Muro A. , Liuzzo M. , Ferrazzini V. , Peltier A. , Gurrieri S. , Michon L. , Giudice G. , Kowalski P. , Boissier P.
Published: August 2017

Detecting renewal of volcanic activity is a challenging task and even more difficult in tropical settings. Continuous measurements of soil CO2 flux were carried out at the Piton de la Fournaise volcano during 2013–2016. Since this site is in the tropics, periods of heavy rainfall are in the norm. Measurements covered volcanic unrest after a hiatus of 3.5 years. We find that while temperature has the strongest effect, extreme rainfall causes short‐term noise. When corrected and filtered from the environmental influence, soil CO2 time series permit to detect a major deep magmatic event during March–April 2014, 3 months before the first eruption of the new activity phase. Correlation with geophysical data sets allows timing of further stages of upward fluid ascent. Our study validates soil CO2 flux monitoring in tropical environments as a valuable tool to monitor magma transfer and to enhance understanding of volcano unrest down to the lithospheric mantle.
Seismotectonics of the 2013 Lushan Mw 6.7 earthquake: Inversion tectonics in the eastern margin of the Tibetan Plateau
Authors: Lu Renqi , Xu Xiwei , He Dengfa , John Suppe , Liu Bo , Wang Fuyun , Tan Xibin , Li Yingqiang
Published: August 2017

On 20 April 2013, an unexpected Mw 6.7 earthquake occurred in Lushan County at the southern Longmen Shan, the eastern margin of the Tibetan Plateau. A high‐resolution seismic reflection profile was combined with near‐surface geological data, earthquake relocation and geodetic measurements, and a recent deep artificial seismic reflection profile to identify the active fault and seismotectonics of this earthquake. Three‐dimensional imaging of the aftershocks was used to identify two planar faults that together form a y shape (f1 and f2). Seismic interpretations suggest that fault f1 did not break through the overlying Mesozoic and Cenozoic rocks and is a typical blind fault. Geodetic measurements suggest that the coseismic deformation is consistent with the geometry and kinematics of shear fault‐bend folding. Deep seismic data indicate the syndepositional nature of fault f1 a preexisting normal fault older than the Triassic, which underwent positive inversion tectonics during the Late Cenozoic. A thrust fault f3 converges with f1 at a depth of approximately 12 km with an accumulated slip 3.6 km. This 2013 Lushan earthquake triggered by blind faults is a hidden earthquake. Blind and reactivated faults increase the potential risk and uncertainty related to earthquakes in the eastern margin of the Tibetan Plateau.
Toward an ice‐free Barents Sea
Authors: Onarheim Ingrid H. , Årthun Marius
Published: August 2017

Arctic winter sea ice loss is most pronounced in the Barents Sea. Here we combine observations since 1850 with climate model simulations to examine the recent record low winter Barents Sea ice extent. We find that the present observed winter Barents Sea ice extent has been reduced to less than one third of the pre‐satellite mean and is lower than the minimum sea ice extent in all multicentury climate model control simulations assessed here. The current observed sea ice loss is furthermore unprecedented in the observational record and appears as an uncommon trend in the long control simulations. In a warming climate, projections from the large ensemble simulation with the Community Earth System Model show a winter ice‐free Barents Sea for the first time within the time period 2061–2088. The large spread in projections of ice‐free conditions highlights the importance of internal variability in driving recent and future sea ice loss.
Modeling fracture propagation and seafloor gas release during seafloor warming‐induced hydrate dissociation
Authors: Stranne C. , O'Regan M. , Jakobsson M.
Published: August 2017

The stability of marine methane hydrates and the potential release of methane gas to the ocean and atmosphere have received considerable attention in the past decade. Sophisticated hydraulic‐thermodynamic models are increasingly being applied to investigate the dynamics of bottom water warming, hydrate dissociation, and gas escape from the seafloor. However, these models often lack geomechanical coupling and neglect how overpressure development and fracture propagation affect the timing, rate, and magnitude of methane escape. In this study we integrate a geomechanical coupling into the widely used TOUGH + Hydrate model. It is shown that such coupling is crucial in sediments with permeability ≤10−16 m2, as fracture formation dramatically affects rates of dissociation and seafloor gas release. The geomechanical coupling also results in highly nonlinear seafloor gas release, which presents an additional mechanism for explaining the widely observed episodic nature of gas flares from seafloor sediments in a variety of tectonic and oceanographic settings.
First spaceborne phase altimetry over sea ice using TechDemoSat‐1 GNSS‐R signals
Authors: Li Weiqiang , Cardellach Estel , Fabra Fran , Rius Antonio , Ribó Serni , Martín‐Neira Manuel
Published: August 2017

A track of sea ice reflected Global Navigation Satellite System (GNSS) signal collected by the TechDemoSat‐1 mission is processed to perform phase altimetry over sea ice. High‐precision carrier phase measurements are extracted from coherent GNSS reflections at a high angle of elevation (>57°). The altimetric results show good consistency with a mean sea surface (MSS) model, and the root‐mean‐square difference is 4.7 cm with an along‐track sampling distance of ∼140 m and a spatial resolution of ∼400 m. The difference observed between the altimetric results and the MSS shows good correlation with the colocated sea ice thickness data from Soil Moisture and Ocean Salinity. This is consistent with the reflecting surface aligned with the bottom of the ice‐water interface, due to the penetration of the GNSS signal into the sea ice. Therefore, these high‐precision altimetric results have potential to be used for determination of sea ice thickness.
Timing of subsurface heat magnitude for the growth of El Niño events
Authors: Ballester Joan , Petrova Desislava , Bordoni Simona , Cash Ben , Rodó Xavier
Published: August 2017

The subsurface heat buildup in the western tropical Pacific and the recharge phase in equatorial heat content are intrinsic elements of El Niño–Southern Oscillation, leading to changes in zonal wind stress, sea surface temperature, and thermocline tilt that characterize the growing and mature phases of El Niño (EN) events. Here we use numerical simulations to study the impact on subsequent EN episodes of a sudden increase or decrease in ocean heat content during the recharge phase and compare results with previous studies in which this perturbation is prescribed earlier during the tilting mode. We found that while not substantially affected by the phase at which a sudden rise in heat content is prescribed, the timing and magnitude of the events are very sensitive to the phase at which a major decrease is imposed. The different response to the phase of increases and decreases substantiates the importance of nonlinear subsurface ocean dynamics to the onset and growth of EN episodes and provides insight into the irreversibility of the events at different stages of the oscillation.
Photochemical determination of O densities in the Martian thermosphere: Effect of a revised rate coefficient
Authors: Fox Jane L. , Johnson Austin S. , Ard Shaun G. , Shuman Nicholas S. , Viggiano Albert A.
Published: August 2017

We investigate the production and loss rates of
in the photochemical equilibrium region of the Martian ionosphere near the subsolar point. We adopt neutral and ion densities measured by the Mars Atmosphere and Volatiles EvolutioN (MAVEN) Neutral Gas and Ion Mass Spectrometer (NGIMS), electron densities and temperatures measured by the Langmuir Probe and Waves, and ion temperatures measured by the Supra‐Thermal and Thermal Ion Composition instruments on the MAVEN spacecraft. Contrary to the conventional wisdom, we find that loss of
by dissociative recombination is balanced mainly by production due to the reaction of O+ with CO2, with a smaller contribution due to the reaction of
with O. We find that the O densities derived from this calculation are larger than those measured by the NGIMS instrument by a factor that averages about 4 over the range of 130–155 km. This general conclusion is supported by a newly measured rate coefficient for the reaction of O with
, which is smaller by a factor of about 6 than the only value in the literature, which was measured 47 years ago.
Statistical study of low‐frequency magnetic field fluctuations near Venus during the solar cycle
Authors: Xiao S. D. , Zhang T. L. , Wang G. Q.
Published: August 2017

We statistically investigate the solar cycle dependence of the magnetic field fluctuations in the frequency range 30–300 MHz based on Venus Express data. We present the spatial distributions of fluctuation properties during three typical periods of the solar cycle, and a comparative study is also performed. With the increase of solar activity, the magnetic field is still quiet in the magnetotail region and the wave intensity becomes weaker in the magnetosheath. The transverse component of fluctuations becomes stronger in the magnetosheath region and weaker in the tail region. The proportion of circularly polarized components to incoherent noise of the fluctuations decreases in the magnetosheath region. The proportion of dominant parallel propagation fluctuations tends to be larger in the nightside magnetosheath, and more perpendicular propagation component is shown in the tail region.
Theoretical basis of the amplitude source location method for volcano‐seismic signals
Authors: Morioka Hanae , Kumagai Hiroyuki , Maeda Takuto
Published: August 2017

The source location method using high‐frequency seismic amplitudes based on the assumption of isotropic radiation of S waves has been used successfully to locate seismic events and tremor at volcanoes. This amplitude source location (ASL) method overcomes the limitations of traditional hypocenter determination methods that use onset arrival times and has great potential to improve volcano‐seismic monitoring and the investigation of source processes of volcano‐seismic signals. However, theoretical justification of the basic assumption used in the ASL method has not been provided in previous studies. In this study, we tested the ASL method by using seismic waveforms simulated with a finite difference method in realistic heterogeneous volcanic structures with intrinsic attenuation and topography. Our results showed that ASL determinations were successful when using waveforms characterized by multiple scattering that can be approximated by the diffusion model. We found that the energy solution of the diffusion model provided an amplitude‐distance relation that is similar to that used in the ASL method. Our results suggest that the ASL method is applicable to high‐frequency seismograms in highly heterogeneous media with transport mean free paths of 103 m or smaller and strong intrinsic attenuation. These medium parameters are consistent with those estimated at various volcanoes. Our study validates the basic assumption of the ASL method and justifies its use to locate the sources of high‐frequency seismic signals observed at volcanoes.
Magma storage beneath Grímsvötn volcano, Iceland, constrained by clinopyroxene‐melt thermobarometry and volatiles in melt inclusions and groundmass glass
Authors: Haddadi B. , Sigmarsson O. , Larsen G.
Published: August 2017

Basalt eruptions at Grímsvötn volcano, Iceland, are generally of low intensity; however, occasionally, an order of magnitude larger eruptions occur. In order to discuss the reasons for this difference, the degassing budget of S and Cl and crystallization conditions of the eruptive magma were determined from volatile concentration measured in melt inclusion (MI) and groundmass glass and thermobarometry, respectively. Tephra of two of the largest historical eruptions (2011 and 1873) and two much smaller eruptions (2004 and 1823) were investigated. Sulfur and Cl concentrations are higher in groundmass glass of the smaller eruptions due to incomplete outgassing caused by melt quenching in contact with glacial water. Sulfur concentration and degassing budget correlate with erupted magma volumes. Higher volatile concentrations of MI from the larger eruptions reflect important recharge of gas‐rich magma from depth. The recharge causes a high‐magnitude eruption followed by increased eruption frequency over the following decades. Pressure and temperature estimates of crystallization are obtained through equilibrium clinopyroxene‐glass pairs, where crystals adjacent to, and in textural equilibrium with, both groundmass glass and that of MI were measured. An average crystallization pressure of 4 ± 1 kbar corresponding to approximately 15 ± 5 km depth was obtained together with a considerable temperature range, 1065–1175°C. Similar crystallization depths are obtained for the basalt of the 2014–2015 Bárðarbunga rifting event and to a low resistivity layer revealed by magnetotelluric surveys. Therefore, an important magma storage depth is inferred at lower crustal depth above the center of the Iceland mantle plume.
Alpha‐Designs
Authors: Williams Emlyn R.
Published: August 2017

In plant and tree breeding, field trials are conducted to compare varieties.
Randomized complete block
(RCB) designs can be used for such trials but usually do not adequately adjust variety means for the effects of environmental variation. It is preferable to subdivide the complete blocks (or replicates) into smaller groups of plots (incomplete blocks) so that environmental variation can be more effectively controlled, and hence, variety comparisons can be more precisely made. Experimental designs with this type of block structure are called resolvable
incomplete block designs
; α‐designs are a particular subclass that have a cyclical method of construction. The advantages of α‐designs are their ease of construction, availability for a wide range of practical parameter values, and near optimality.
A Review of Portfolio Choice Based on Stochastic Dominance
Authors: Post Thierry
Published: August 2017

Theoretical concepts together with estimation and optimization methods for portfolio choice based on stochastic dominance are reviewed. Distinction is drawn between the concepts of pairwise dominance, admissibility, optimality, efficiency, and spanning. Results of selected empirical studies and practical applications are discussed.

JEL Classification:C61, D81, G11
Adversarial Risk Analysis
Authors: Insua David Ríos , Banks David , Ríos Jesus , González‐Ortega Jorge
Published: August 2017

Adversarial risk analysis (ARA) is an emergent paradigm for supporting a decision‐maker who faces adversaries in problems in which the consequences are random and depend on the actions of all participating agents. We provide an introduction to ARA with a focus on problems in statistical decision theory.
Age‐Related Vascularization and Ossification of Joints in Children: An International Pilot Study to Test Multiobserver Ultrasound Reliability
Authors: Windschall Daniel , Collado Paz , Vojinovic Jelena , Magni‐Manzoni Silvia , Balint Peter , Bruyn George A. W. , Hernandez‐Diaz Cristina , Nieto Juan Carlos , Ravagnani Viviana , Tzaribachev Nikolay , Iagnocco Annamaria , D'Agostino Maria Antonietta , Naredo Esperanza ,   the Outcome Measures in Rheumatology Pediatric Ultrasound Subtask Force
Published: August 2017

Objective

To determine the intra‐ and interobserver reliability of ultrasound (US)‐detected age‐related joint vascularization and ossification grading in healthy children.

Methods

Following standardized image acquisition and machine setting protocols, 10 international US experts examined 4 joints (wrist, second metacarpophalangeal joint, knee, and ankle) in 12 healthy children (divided into 4 age groups: 2–4, 5–8, 9–12, and 13–16 years). Gray‐scale was used to detect the ossification grade, and power Doppler ultrasound (PDUS) was used to detect physiologic vascularization. Ossification was graded from 0 (no ossification) to 3 (complete ossification). A positive PDUS signal was defined as any PDUS signal inside the joint. Kappa statistics were applied for intra‐ and interobserver reliability.

Results

According to the specific joint and age, up to 4 solitary PDUS signals (mean 1.5) were detected within each joint area with predominant localization of the physiologic vascularization in specific anatomic positions: fat pad, epiphysis, physis, and short bone cartilage. The kappa values for ossification grading were 0.87 (range 0.85–0.91) and 0.58 for intra‐ and interobserver reliability, respectively. The bias‐adjusted kappa values for intra‐ and interobserver reliability were 0.71 (range 0.44–1.00) and 0.69, respectively.

Conclusion

Detection of normal findings (i.e., grading of physiologic ossification during skeletal maturation and identification of physiologic vessels) can be highly reliable by using clear definitions and a standardized acquisition protocol. These data will permit development of a reliable and standardized US approach for evaluating pediatric joint pathologies.