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Benchmark of swarm robotics distributed techniques in a search task

Couceiro, Micael S.; Vargas, Patricia A.; Rocha, Rui P.; Ferreira, Nuno M. F.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.49%
This paper presents a survey on multi-robot search inspired by swarm intelligence by further classifying and discussing the theoretical advantages and disadvantages of the existing studies. Subsequently, the most attractive techniques are evaluated and compared by highlighting their most relevant features. This is motivated by the gradual growth of swarm robotics solutions in situations where conventional search cannot find a satisfactory solution. For instance, exhaustive multi-robot search techniques, such as sweeping the environment, allow for a better avoidance of local solutions but require too much time to find the optimal one. Moreover, such techniques tend to fail in finding targets within dynamic and unstructured environments. This paper presents experiments conducted to benchmark five state-of-the-art algorithms for cooperative exploration tasks. The simulated experimental results show the superiority of the previously presented Robotic Darwinian Particle Swarm Optimization (RDPSO), evidencing that sociobiological inspiration is useful to meet the challenges of robotic applications that can be described as optimization problems (e.g., search and rescue). Moreover, the RDPSO is further compared with the best performing algorithms within a population of 14 e-pucks. It is observed that the RDPSO algorithm converges to the optimal solution faster and more accurately than the other approaches without significantly increasing the computational demand...

Fault detection in the Tennessee Eastman benchmark process using dynamic principal components analysis based on decorrelated residuals (DPCA-DR)

Rato, Tiago J.; Reis, Marco S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.49%
Current multivariate control charts for monitoring large scale industrial processes are typically based on latent variable models, such as principal component analysis (PCA) or its dynamic counterpart when variables present auto-correlation (DPCA). In fact, it is usually considered that, under such conditions, DPCA is capable to effectively deal with both the cross- and auto-correlated nature of data. However, it can easily be verified that the resulting monitoring statistics (T2 and Q, also referred by SPE) still present significant auto-correlation. To handle this issue, a set of multivariate statistics based on DPCA and on the generation of decorrelated residuals were developed, that present low auto-correlation levels, and therefore are better positioned to implement SPC in a more consistent and stable way (DPCA-DR). The monitoring performance of these statistics was compared with that from other alternative methodologies for the well-known Tennessee Eastman process benchmark. From this study, we conclude that the proposed statistics had the highest detection rates on 19 out of the 21 faults, and are statistically superior to their PCA and DPCA counterparts. DPCA-DR statistics also presented lower auto-correlation, which simplifies their implementation and improves their reliability.

Fundos de ações com benchmark em renda fixa mais do que compensam o investidor relativamente aos fundos com benchmark em renda variável?

Moraes, Gustavo de Paula
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Dissertação
PT_BR
Relevância na Pesquisa
36.95%
Este trabalho estuda o diferencial de retorno entre fundos de ações com benchmark em índices de renda fixa e fundos de ações com benchmark em índices de renda variável. A escolha de um índice de renda fixa como benchmark para um FIA, em média tende a ser pior para o cotista, pois gera um potencial de ganho financeiro para o gestor não associado ao real valor por ele criado. Portanto, como a remuneração dos gestores através da taxa de performance depende em parte do benchmark escolhido, fundos com benchmark em renda fixa deveriam apresentar melhores desempenhos a fim de compensarem seus cotistas por este custo. Os resultados encontrados sugerem que os gestores de fundos com benchmark em renda fixa obtêm um retorno líquido de taxas de performance e administração superior para seus cotistas e também apresentam uma menor correlação com o Índice Bovespa.; This paper analyses the difference between returns of equities funds that have fixed-income index as benchmark and equities funds that have stocks index as benchmark. The choice of a fixed-income index as benchmark for an equities fund on average tends to be worst for the investor as it creates a potential financial recompense for the fund manager that is not associated with its performance. So...

Análise dos coeficientes de desempenho técnico e econômico que caracterizam as unidades produtoras benchmark na atividade leiteira no RS

Menegaz, Edna; Padula, Antonio Domingos; Krug, Ernesto Enio Budke; Santos, Omar Inacio Benedetti; Rathmann, Régis
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
Relevância na Pesquisa
26.78%
Para auxiliar o setor produtivo a se profissionalizar na atividade leiteira, a Avipal Alimentos S.A. implementou o Sistema Benchmarking, o qual serviu como estratégia para melhorar o desempenho técnico e econômico das Unidades Produtoras do Estado do Rio Grande do Sul. Assim, o presente trabalho tem como objetivo avaliar a evolução dos coeficientes de desempenho técnico e econômico das Unidades Produtoras benchmark que participaram dos três períodos de análise do Sistema Benchmarking. Para tanto, foi realizado um estudo de caráter descritivo e exploratório, o qual possibilitou avaliar a pertinência e os efeitos dessa técnica sobre o setor primário da atividade leiteira. Após essa avaliação, concluiu-se que a técnica de benchmarking tem exercido um papel fundamental para o processo de tomada de decisão e gestão das Unidades Produtoras. Essa técnica tem auxiliado os Produtores Benchmark a medir o grau de eficiência da atividade leiteira, bem como a detectar os pontos fracos do sistema produtivo. Além disso, a divulgação das informações obtidas através da identificação das Unidades Produtoras benchmark, poderá auxiliar os demais envolvidos com a cadeia produtiva do leite a direcionarem suas competências para o fortalecimento das atividades desempenhadas pelo setor produtivo.; To aid the productive sector becoming professional in the dairy activity...

Um benchmark voltado a analise de desempenho de sistemas de informações geograficas

Ricardo Rodrigues Ciferri
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/06/1995 PT
Relevância na Pesquisa
26.81%
A enorme quantidade e a natureza dos dados armazenados por aplicações que utilizam sistemas de informações geográficas (SIGs) implicam em alterações ou extensões nos métodos de acesso, otimizadores de consulta e linguagens de consulta estabelecidos para sistemas gerenciadotes de banco de dados (SGBDs) convencionais. Com isto, diferentes soluções têm sido apresentadas, tornando-se imprescindível a criação de algum mecanismo que possa medir a eficiência destas soluções para auxiliar o direcionamento de futuros trabalhos de pesquisas. Para tal propósito é utilizada, nesta dissertação, a técnica experimental de benchmark. Esta dissertação propõe a carga de trabalho e caracteriza os dados de um benchmark voltado à análise de desempenho de SIGs. A carga de trabalho do benchmark é composta por um conjunto de transações primitivas, especificadas em alto nível, que podem ser utilizadas para a formação de transações mais complexas. Estas transações primitivas são predominantemente orientadas aos dados espaciais, sendo, a priori, independentes do formato de dados utilizado (raster ou vetorial). A caracterização dos dados do benchmark foi efetuada em termos dos tipos de dados necessários para a representação de aplicações georeferenciadas...

Capacidade de replicação dos exchange traded funds: o caso do Eur/Usd

Correia, Filipe André Machado
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2013 POR
Relevância na Pesquisa
26.84%
Dissertação submetida como requisito parcial para obtenção do grau de Mestre em Economia Monetária e Financeira / Sistema de Classificação JEL: G12 e G15; Os Exchange Traded Funds (ETF’s) são fundos de investimento transacionados em bolsa cuja importância tem crescido substancialmente nos últimos anos. Esta tese analisa o seu principal objetivo: replicação diária do benchmark. São objeto de estudo dez ETF’s, cujo benchmark é a taxa de câmbio EUR/USD, incluindo ETF’s standard e alavancados, transacionados em diversas bolsas (New York Stock Exchange, London Stock Exchange, Deutsche Börse e Borsa Italiana). O principal foco desta dissertação é a capacidade de replicação dos movimentos diários da taxa de câmbio EUR/USD. Em segundo lugar, é testada a importância de pontos de referência para os investidores, como os máximos e mínimos históricos do EUR/USD nos flows diários dos ETF’s. Por fim, é analisado se ETF’s são transacionados pelo seu “justo valor”, ou se por norma há desvios do seu preço face ao NAV (mispricing). Os resultados mostram que, de todos os ETF’s, apenas um replica fielmente o benchmark. Contudo, todos os fundos obtiveram tracking errors baixos, alguns até nulos, e betas estimados próximos dos betas objetivos...

A simulation benchmark to evaluate the performance of advanced control techniques in biological wastewater treatment plants

Sotomayor,O.A.Z.; Park,S.W.; Garcia,C.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2001 EN
Relevância na Pesquisa
36.74%
Wastewater treatment plants (WWTP) are complex systems that incorporate a large number of biological, physicochemical and biochemical processes. They are large and nonlinear systems subject to great disturbances in incoming loads. The primary goal of a WWTP is to reduce pollutants and the second goal is disturbance rejection, in order to obtain good effluent quality. Modeling and computer simulations are key tools in the achievement of these two goals. They are essential to describe, predict and control the complicated interactions of the processes. Numerous control techniques (algorithms) and control strategies (structures) have been suggested to regulate WWTP; however, it is difficult to make a discerning performance evaluation due to the nonuniformity of the simulated plants used. The main objective of this paper is to present a benchmark of an entire biological wastewater treatment plant in order to evaluate, through simulations, different control techniques. This benchmark plays the role of an activated sludge process used for removal of organic matter and nitrogen from domestic effluents. The development of this simulator is based on models widely accepted by the international community and is implemented in Matlab/Simulink (The MathWorks...

Protein-Protein Docking Benchmark Version 3.0

Hwang, Howook; Pierce, Brian; Mintseris, Julian; Janin, Joël; Weng, Zhiping
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/11/2008 EN
Relevância na Pesquisa
26.81%
We present version 3.0 of our publicly available protein-protein docking benchmark. This update includes 40 new test cases, representing a 48% increase from Benchmark 2.0. For all of the new cases, the crystal structures of both binding partners are available. As with Benchmark 2.0, SCOP1 (Structural Classification of Proteins) was used to remove redundant test cases. The 124 unbound-unbound test cases in Benchmark 3.0 are classified into 88 rigid-body cases, 19 medium difficulty cases, and 17 difficult cases, based on the degree of conformational change at the interface upon complex formation. In addition to providing the community with more test cases for evaluating docking methods, the expansion of Benchmark 3.0 will facilitate the development of new algorithms that require a large number of training examples. Benchmark 3.0 is available to the public at http://zlab.bu.edu/benchmark.

Immunotoxicity of Perfluorinated Alkylates: Calculation of Benchmark Doses Based on Serum Concentrations in Children

Grandjean, Philippe; Budtz-Jørgensen, Esben
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.81%
Background: Immune suppression may be a critical effect associated with exposure to perfluorinated compounds (PFCs), as indicated by recent data on vaccine antibody responses in children. Therefore, this information may be crucial when deciding on exposure limits. Methods: Results obtained from follow-up of a Faroese birth cohort were used. Serum-PFC concentrations were measured at age 5 years, and serum antibody concentrations against tetanus and diphtheria toxoids were obtained at age 7 years. Benchmark dose results were calculated in terms of serum concentrations for 431 children with complete data using linear and logarithmic curves, and sensitivity analyses were included to explore the impact of the low-dose curve shape. Results: Under different linear assumptions regarding dose-dependence of the effects, benchmark dose levels were about 1.3 ng/mL serum for perfluorooctane sulfonic acid and 0.3 ng/mL serum for perfluorooctanoic acid at a benchmark response of 5%. These results are below average serum concentrations reported in recent population studies. Even lower results were obtained using logarithmic dose–response curves. Assumption of no effect below the lowest observed dose resulted in higher benchmark dose results, as did a benchmark response of 10%. Conclusions:The benchmark dose results obtained are in accordance with recent data on toxicity in experimental models. When the results are converted to approximate exposure limits for drinking water...

Análise e aperfeiçoamento de benchmark OLTP para avaliação de desempenho em SGBD

Ávila Rêgo Pessoa, Fábio; Carolina Brandão Salgado, Ana (Orientador)
Fonte: Universidade Federal de Pernambuco Publicador: Universidade Federal de Pernambuco
Tipo: Outros
PT_BR
Relevância na Pesquisa
36.78%
Resumo: Medir o desempenho de ambientes de missão crítica é uma tarefa importante para consumidores e fornecedores de software e hardware. O desenvolvimento de metodologias (ou benchmarks) que viabilizem a comparação do desempenho conjunto de software e hardware foi objeto de estudo na comunidade de Banco de Dados, principalmente nos anos 80 e 90. Nos últimos 20 anos, foram propostos benchmarks que propõem métricas relevantes ao negócio do usuário final, tais como número de transações realizadas por intervalo de tempo e custo de cada transação. Muitas vezes, estes benchmarks modelam o funcionamento de uma aplicação completa, e têm destaque na mídia em anúncios de marketing dos fornecedores de hardware e software, com o objetivo de demonstrar desempenho superior ao de produtos concorrentes. Apesar da importância dos benchmarks para diversas áreas, não há trabalhos de pesquisa que realizam avaliações críticas de benchmarks, há poucos resultados experimentais mostrando possíveis melhorias nos benchmarks, e este trabalho fica sempre confinado nas organizações de benchmark. Mesmo com a abertura das especificações e resultados, uma análise mais crítica e minuciosa pode revelar pontos de melhoria nos benchmarks e nos seus processos de auditoria...

Spatial Star Shema Benchmark – um benchmark para data warehouse geográfico

Nascimento, Samara Martins do; Times, Valéria Cesário (Orientadora)
Fonte: Universidade Federal de Pernambuco Publicador: Universidade Federal de Pernambuco
Tipo: Dissertação
BR
Relevância na Pesquisa
36.81%
A técnica experimental de avaliação de desempenho utilizada em aplicações e sistemas de bancos de dados é composta principalmente da técnica de benchmark, que consiste em um conjunto de testes experimentais previamente definidos e posteriormente executados para obtenção de resultados de desempenho. Data Warehouses Geográficos (DWG) permitem o armazenamento de geometrias dos objetos que representam localizações na superfície terrestre e possibilitam o processamento de consultas analíticas e multidimensionais. Os benchmarks TPC-D, TPC-H e SSB são utilizados para avaliar o desempenho de Data Warehouses Convencionais. O benchmark Spadawan é utilizado para avaliar o desempenho de Data Warehouses Geográficos. Contudo, os benchmarks anteriores não conseguem ser considerados abrangentes, devido a sua limitada carga de trabalho. Desta forma, nesta dissertação, propomos um novo benchmark, chamado Spatial Star Schema Benchmark, ou Spatial SSB, projetado especialmente para realizar a avaliação de desempenho de consultas em ambientes de DWG. As principais contribuições do Spatial SSB estão concentradas em três pontos. Primeiro, o Spatial SSB utiliza três tipos de dados geométricos (i.e. pontos, linhas e polígonos), propostos em um esquema híbrido. Além disto...

Um benchmark para avaliação de técnicas de busca no contexto de análise de Mutantes sql; A benchmark to evaluation of search techniques in the context of sql mutation analysis

Queiroz, Leonardo Teixeira
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ciência da Computação (INF); Instituto de Informática - INF (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ciência da Computação (INF); Instituto de Informática - INF (RG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
36.86%
One of the concerns in test Applications Database (ADB) is to keep the operating and computational costs low. In the context of the ADB, one way to collaborate with this assumption is ensuring that the Test Databases (TDB) are small, but effective in revealing defects of SQL statements. Such bases can be constructed or obtained by the reduction of Production Databases (PDB). In the reductions case, there are combinatorial aspects involved that require the use of a specific technique for their implementation. In this context, in response to a deficiency identified in the literature, this work aims to build and provide a benchmark to enable performance evaluation, using SQL Mutation Analysis, any search technique that intends to conduct databases reductions. Therefore, to exercise the search techniques, the benchmark was built with two scenarios where each one is composed of a PDB and a set of SQL statements. In addition, as a reference for search techniques, it also contains performance of data database randomly reduced. As a secondary objective of this work, from the experiments conducted in the construction of the benchmark, analyses were made with the results obtained to answer important questions about what factors are involved in the complexity of SQL statements in the context of Test Mutation. A key finding in this regard was on the restrictiveness of SQL commands...

International Asset Allocations and Capital Flows : The Benchmark Effect

Raddatz, Claudio; Schmukler, Sergio L.; Williams, Tomas
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
36.86%
This paper studies channels through which well-known benchmark indexes impact asset allocations and capital flows across countries. The study uses unique monthly micro-level data of benchmark compositions and mutual fund investments during 1996-2012. Benchmarks have important effects on equity and bond mutual fund portfolios across funds with different degrees of activism. Benchmarks explain, on average, around 70 percent of country allocations and have significant impact even on active funds. Benchmark effects are important after controlling for industry, macroeconomic, and country-specific, time-varying effects. Reverse causality does not drive the results. Exogenous, pre-announced changes in benchmarks result in movements in asset allocations mostly when these changes are implemented (not when announced). By impacting country allocations, benchmarks affect capital flows across countries through direct and indirect channels, including contagion. They explain apparently counterintuitive movements in capital flows...

Project Report of the Benchmark Statistics Service (BEST)

Vallee, Laura
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper
EN
Relevância na Pesquisa
36.6%
As part of the Australian Partnership for Sustainable Repositories’ aim to improve the management of scholarly digital assets, the Benchmark Statistics Service project (BEST)i was designed to enhance the type and quality of statistical information about repository holdings and usage. The problem to be solved relates to the strategic need for better, standardised, statistical information to inform a wide range of policy and funding decisions within the scholarly communications cycle. In order to address this need support was secured for APSR to manage a short pilot project, which was initially envisioned to include the production of a pilot harvesting and aggregation service. Due to personnel and time restraints the project scope was revised in October 2007 to identify an approach and initiate the design of a pilot service, providing the framework for further development.; Australian Partnership for Sustainable Repositories; The Benchmark Statistics Service Project (BEST) was designed to enhance the type and quality of statistical informations about repository holdings and usage. It was recognised that defining universal standards and enforcing compliance were well beyond the scope of a short project. Instead, the BEST project considered existing standards and works in progress...

Damage detection in phase II structural health monitoring benchmark problem using Bayesian designed artificial neural network

Ng, C.T.
Fonte: Hong Kong Polytechnic University; CD Publicador: Hong Kong Polytechnic University; CD
Tipo: Conference paper
Publicado em //2013 EN
Relevância na Pesquisa
36.6%
Pattern recognition using artificial neural network (ANN) is one of the promising approaches for detecting damages in structures. The basic idea of applying ANN in structural damage detection is to treat the calculated pattern features from a structural model as input and the corresponding damage scenarios as target in training an ANN. The trained ANN is then able to estimate the damage scenario by fitting the measured pattern features to the input of it. However, the design of the ANN is critical to the damage detection performance. This study presents a Bayesian model class selection method for optimal design of the ANN based on the given set of input-target training pairs, and hence, it avoids any subjective judgment and ad hoc assumption in the ANN design. The ANN designed by the Bayesian model class selection was applied to detect damages in the IASC-ASCE Structural Health Monitoring (SHM) Phase II Simulated Benchmark structure. In this study the damage induced changes in modal parameters were used as pattern features in the damage identification. Four damage cases were considered, in which single and multiples damages were considered in the IASC-ASCE SHM Phase II Benchmark structure. The results have shown that the ANN designed by the Bayesian model class selection method was able to accurately identify the damage locations and severities in all damage cases.; C.T. Ng

AdaptBenchmark : el benchmark adaptativo universal

Díaz Ponce, Antonio
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/bachelorThesis; info:eu-repo/semantics/masterThesis Formato: application/pdf
SPA
Relevância na Pesquisa
36.88%
Desde la primera aparición de las plataformas de computación, ha sido necesaria la comparación del rendimiento de los distintos productos. El término benchmark emerge a finales del siglo XIX, definido como un punto de referencia en la toma de medidas. Actualmente, este tema está más relacionado con herramientas software que evalúan el rendimiento del ordenador. Este proyecto trata sobre la definición, creación y evaluación de un conjunto de benchmarks para tomar medidas del rendimiento de los microprocesadores. Lo hemos denominado AdaptBenchmark: el benchmark adaptativo universal. Este benchmark incluye diferentes test que evalúan varias características de la arquitectura de un procesador. En este documento explicamos la metodología que hemos seguido durante el desarrollo del AdaptBenchmark. Detallamos la estructura interna del software, que ha sido concebida para evaluar el rendimiento de modernos procesadores con varios núcleos. AdaptBenchmark mide el tiempo de ejecución y eventos internos como: fallos caché en L1 y L2, tráfico de bus o fallos TLB. Esta información es recogida utilizando contadores hardware y resumida mediante gráficas. Para cada test desarrollamos un estudio extensivo del desarrollo de procesador así como un análisis de las interacciones entre software y el correspondiente hardware. Además...

Application of Bayesian-designed artificial neural networks in phase II structural health monitoring benchmark studies

Ng, C.T.
Fonte: Institution of Engineers, Australia Publicador: Institution of Engineers, Australia
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
36.6%
This paper presents the results of a study into the use of pattern recognition as a method for detecting damage in structures. Pattern recognition is achieved by the use of artificial neural networks (ANNs), however, these require careful design because the number of hidden layers and the number of neurons in each hidden layer are critical to the ANN's performance. In the current study, a Bayesian model class selection method was employed to select an optimal ANN model class that avoids ad hoc assumptions and subjective decisions in the ANN design. The objective of the research was to provide an extended study of the proposed method using the IASC-ASCE Structural Health Monitoring Phase II Simulated Benchmark Structure. Damage-induced modal parameter changes were used as a pattern feature in damage detection. Analysis showed that the proposed method is able to successfully identify damages in the benchmark structure.; C-T Ng

Implementation of the BLAS Level 3 and LINPACK benchmark on the AP1000

Brent, Richard P; Strazdins, Peter
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 221893 bytes; 356 bytes; application/pdf; application/octet-stream
EN_AU
Relevância na Pesquisa
36.6%
This paper describes an implementation of Level 3 of the Basic Linear Algebra Sub-program (BLAS-3) library and the LINPACK Benchmark on the Fujitsu AP1000. The performance of these applications is regarded as important for distributed memory architectures such as the AP1000. We discuss the techniques involved in optimizing these applications without significantly sacrificing numerical stability. Many of these techniques may also be applied to other numerical applications. They include the use of software pipelining and loop unrolling to optimize scalar processor computation, the utilization of fast communication primitives on the AP1000 (particularly row and column broadcasting using wormhole routing), blocking and partitioning methods, and `fast' algorithms (using reduced floating point operations). These techniques enable a performance of 85-90% of the AP1000's theoretical peak speed for the BLAS Level 3 procedures and up to 80% for the LINPACK benchmark.; no

Correlation of In  Vivo Versus In Vitro Benchmark Doses (BMDs) Derived From Micronucleus Test Data: A Proof of Concept Study

Soeteman-Hernández, Lya G.; Fellows, Mick D.; Johnson, George E.; Slob, Wout
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
36.49%
In this study, we explored the applicability of using in vitro micronucleus (MN) data from human lymphoblastoid TK6 cells to derive in vivo genotoxicity potency information. Nineteen chemicals covering a broad spectrum of genotoxic modes of action were tested in an in vitro MN test using TK6 cells using the same study protocol. Several of these chemicals were considered to need metabolic activation, and these were administered in the presence of S9. The Benchmark dose (BMD) approach was applied using the dose-response modeling program PROAST to estimate the genotoxic potency from the in vitro data. The resulting in vitro BMDs were compared with previously derived BMDs from in vivo MN and carcinogenicity studies. A proportional correlation was observed between the BMDs from the in vitro MN and the BMDs from the in vivo MN assays. Further, a clear correlation was found between the BMDs from in vitro MN and the associated BMDs for malignant tumors. Although these results are based on only 19 compounds, they show that genotoxicity potencies estimated from in vitro tests may result in useful information regarding in vivo genotoxic potency, as well as expected cancer potency. Extension of the number of compounds and further investigation of metabolic activation (S9) and of other toxicokinetic factors would be needed to validate our initial conclusions. However...

Rethinking benchmark dates in international relations

Buzan, Barry; Lawson, George
Fonte: SAGE Publications on behalf of the Standing Group on International Relations (SGIR) of the ECPR Publicador: SAGE Publications on behalf of the Standing Group on International Relations (SGIR) of the ECPR
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /06/2014 EN; EN
Relevância na Pesquisa
26.88%
International Relations (IR) has an ‘orthodox set’ of benchmark dates by which much of its research and teaching is organized: 1500, 1648, 1919, 1945 and 1989. This article argues that IR scholars need to question the ways in which these orthodox dates serve as internal and external points of reference, think more critically about how benchmark dates are established, and generate a revised set of benchmark dates that better reflects macro-historical international dynamics. The first part of the article questions the appropriateness of the orthodox set of benchmark dates as ways of framing the discipline’s self-understanding. Sections two and three look at what counts as a benchmark date, and why. We systematise benchmark dates drawn from mainstream IR theories (realism, liberalism, constructivism/English School and sociological approaches) and then aggregate their criteria. Part four of the article uses this exercise to construct a revised set of benchmark dates which can widen the discipline’s theoretical and historical scope. We outline a way of ranking benchmark dates and suggest a means of assessing recent candidates for benchmark status. Overall, the article delivers two main benefits: first, an improved heuristic by which to think critically about foundational dates in the discipline; second...