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1

Canine heartworm disease in Porto Velho: first record, distribution map and occurrence of positive mosquitoes.  

PubMed

The aim of this study was to make the first report on canine heartworm disease in the state of Rondônia and confirm its transmission in this state. Blood samples were randomly collected from 727 dogs in the city of Porto Velho. The samples were analyzed to search for microfilariae and circulating antigens, using three different techniques: optical microscopy on thick blood smears stained with Giemsa; immunochromatography; and PCR. Mosquitoes were collected inside and outside the homes of all the cases of positive dogs and were tested using PCR to search for DNA of Dirofilaria immitis. Ninety-three blood samples out of 727 (12.8%) were positive according to the immunoassay technique and none according to the thick smear method. Among the 93 positive dogs, 89 (95.7%) were born in Porto Velho. No difference in the frequency of infection was observed between dogs raised indoors and in the yard. PCR on the mosquitoes resulted in only one positive pool. This result shows that the transmission of canine heartworm disease is occurring in the city of Porto Velho and that there is moderate prevalence among the dogs. The techniques of immunochromatography and PCR were more effective for detecting canine heartworm than thick blood smears. The confirmation of canine heartworm disease transmission in Porto Velho places this disease in the ranking for differential diagnosis of pulmonary nodules in humans in Rondônia. PMID:24473882

Ogawa, Guilherme Maerschner; da Cruz, Edson Neves; Cunha, Príscila Nayara Araújo; Camargo, Luís Marcelo Aranha

2013-01-01

2

Dental maturational sequence and dental tissue proportions in the early Upper Paleolithic child from Abrigo do Lagar Velho, Portugal.  

PubMed

Neandertals differ from recent and terminal Pleistocene human populations in their patterns of dental development, endostructural (internal structure) organization, and relative tissue proportions. Although significant changes in craniofacial and postcranial morphology have been found between the Middle Paleolithic and earlier Upper Paleolithic modern humans of western Eurasia and the terminal Pleistocene and Holocene inhabitants of the same region, most studies of dental maturation and structural morphology have compared Neandertals only to later Holocene humans. To assess whether earlier modern humans contrasted with later modern populations and possibly approached the Neandertal pattern, we used high-resolution microtomography to analyze the remarkably complete mixed dentition of the early Upper Paleolithic (Gravettian) child from Abrigo do Lagar Velho, Portugal, and compared it to a Neandertal sample, the late Upper Paleolithic (Magdalenian) child of La Madeleine, and a worldwide extant human sample. Some aspects of the dental maturational pattern and tooth endostructural organization of Lagar Velho 1 are absent from extant populations and the Magdalenian specimen and are currently documented only among Neandertals. Therefore, a simple Neandertal versus modern human dichotomy is inadequate to accommodate the morphostructural and developmental variation represented by Middle Paleolithic and earlier Upper Paleolithic populations. These data reinforce the complex nature of Neandertal-modern human similarities and differences, and document ongoing human evolution after the global establishment of modern human morphology. PMID:20080622

Bayle, Priscilla; Macchiarelli, Roberto; Trinkaus, Erik; Duarte, Cidália; Mazurier, Arnaud; Zilhão, João

2010-01-26

3

Um modelo para analisar o problema de filas em caixas de supermercados: um estudo de caso  

Microsoft Academic Search

In this study we applied queueing theory to analyze the problem of congestion in supermarket check- outs. We are particularly concerned with modeling the mean user waiting time in the queue, viewed as an important component of the user service, as a function of the capacity of the system (i.e., the number of cashiers in a given time period). Three

Reinaldo Morabito; Flavio C. R. de Lima

2000-01-01

4

CLASSIFICAÇÃO DA COBERTURA VEGETAL E CAPACIDADE DE USO DA TERRA NA REGIÃO DO CARIRI VELHO (PARAÍBA), ATRAVÉS DE SENSORIAMENTO REMOTO E GEOPROCESSAMENTO  

Microsoft Academic Search

The main objective of this study is the better use of our natural resources for a part of Cariri Velho region of Paraíb a State (NE of Brazil). Under this investigation, the supervised classification (MAXCLAS) was made using the SPOT images by ERDAS Software and thirteen land use\\/land cover classes were detected, which further were evaluated by various GIS programs

HARENDRA S. TEOTIA; IVANDRO DE FRANÇA DA SILVA; ROBERTO DOS SANTOS; JOSÉ FRANCIMAR VELOSO JUNIOR; JORGE LUÍS DE GÓIS GONÇALVES; Pesquisas Espaciais; Caixa Postal

2003-01-01

5

Mineralogy and geochemistry of the Paleoproterozoic, tin-mineralized Bom Jardim granite of the Velho Guilherme Suite, eastern Amazonian craton  

NASA Astrophysics Data System (ADS)

The Bom Jardim granite is located to the south of São Felix do Xingu town and is intrusive in the intermediate to felsic volcanic rocks of the Uatumã Group. It is formed dominantly of coarse- to medium-grained isotropic monzogranite and syenogranite, both affected by intense late- to post-magmatic alteration. Biotite, generally chloritized, is the main primary mafic phase, with rare amphibole being found in the monzogranite. Hydrothermally altered and greisenized rocks, containing small primary concentrations of cassiterite + wolframite, as well as quartz veins with millimeter- to centimeter-sized crystals of wolframite + pyrite + fluorite occur in pervasively altered cupolas. Presently, alluvial cassiterite and wolframite (±columbite, tantalite) are mined in the Pedra Preta mine, located in the northern part of the pluton. SEM data showed that Sn-W mineralization is dominantly associated with syenogranite and greisenized rocks. EDS Semi-quantitative analysis revealed that the zircon crystals of the Bom Jardim granite are characteristically enriched in Hf, Y, U, and Th and display Zr/Hf ratios decreasing from monzogranite/leucomonzogranite toward syenogranite and greisenized syenogranite rocks, suggesting that magmatic differentiation significantly contributed for this particular feature. The Bom Jardim granite is slightly peraluminous and displays geochemical affinities with A-type granites. The Bom Jardim granite varieties evolved dominantly by fractional crystallization and their REE patterns are similar to those of the tin-specialized granites of the Velho Guilherme suite. It is concluded that the more evolved granites and associated greisenized rocks of the Bom Jardim pluton are tin-specialized granites. The similarities observed between the granites of the Velho Guilherme suite and the Bom Jardim granite allow to include the latter in this important granite suite.

Lamarão, Claudio Nery; Cordovil Pinho, Sabrina Cristina; de Paiva, Antonio Lima; Galarza, Marco Antônio

2012-10-01

6

Sistema de Desafios Abertos Inteligentes: um incremento computacional lúdico para se trabalhar o problema da aprendizagem  

Microsoft Academic Search

The work contextually in general lines action of the Educational Technology applying techniques of Artificial Intelligence with the theory of Jean Piaget. Such research, still in implementation phase, has as hypothesis that from a playful increment, supported for IA, will be possible to reach learning situations and, consequently, of cognitive development for its user. This if gives by means of

Othon C. Bastos Filho; Margarete Axt; Sofiane Labidi; Paloma Dias Silveira

7

Mortalidade materna: um estudo dos níveis e das causas de óbitos no México e no Brasil entre 2000 e 2004  

Microsoft Academic Search

A mortalidade materna se apresenta como um grave problema social e de saúde pública, representando um importante indicador para avaliar as condições de assistência à saúde feminina. A preocupação com as mortes maternas está relacionada principalmente às repercussões sociais e econômicas que a morte de uma mulher acarreta para as famílias. Isto porque as mulheres assumem atribuições centrais na organização

Ana Paula Belon

8

Solução Paralela em Agregado de PCs de um Código de Elementos Finitos Aplicado à Elasticidade Linear  

Microsoft Academic Search

Resumo. Este trabalho apresenta os resultados comparativos de desempenho de códigos paralelos, baseados no método dos elementos finitos aplicado à elasticidade linear para problemas estruturais, que utilizam o método dos gradientes conjugados para solução do sistema de equações. Os programas foram executados em um agregado de PCs, por ser uma opção economicamente viável, já que utiliza tecnologia depurada de alta

Flávia R. Villa Verde; Roberta R. Ferreira; Gerson H. Pfitscher

9

El problema de estabilidad de los sistemas Hamiltonianos multidimensionales  

NASA Astrophysics Data System (ADS)

Se revisarán los aspectos básicos del problema de estabilidad de sistemans Hamiltonianos N-dimensionales, haciendo especial énfasis en los posibles mecanismos que dan lugar a la aparición de ``caos": overlap de resonancias, difusión de Arnol'd y otros procesos difusivos alternativos. Se mencionarán los aspectos aún no resueltos sobre la estabilidad de los sistemas con N > 2. Finalmente, se discutirá cuáles de estos mecanismos podrían tener alguna relevancia en la dinámica de sistemas estelares y planetarios.

Cincotta, P. M.

10

Problema misto e soluzioni quasiperiodiche dell’equazione delle onde  

Microsoft Academic Search

\\u000a Sunto  Ricordate le principali proprietà delle funzioni quasi-periodiche a valori in uno spazio di Banach, si espongono alcuni recenti\\u000a risultati concernenti l’analisi del problema misto, secondo Hadamard, per l’equazione non omogenea delle onde. In particolare\\u000a si indicano i teoremi seguenti: I) tra tutte le soluzioni ad energia limitata, nel’intervallo — ? t < + ?, ne esiste una, e una sola,

Luigi Amerio

1960-01-01

11

Algunos problemas de la tintura de la lana y sus nuevas técnicas  

Microsoft Academic Search

La introducción de la Marca Lana en la industria lanera ha planteado algunos problemas a los tintoreros. Estos problemas son siempre los mismos. Algunos tintoreros los han resuelto con éxito, y otros están en camino de hallar la solución. No obstante, dado que estos problemas son prácticamente comunes a todos, expondré algunas posibilidades que permiten generalmente mejorar los procedimientos de

A Iancovici

1970-01-01

12

Ponencia MICROSISTEMAS MOTIVACIONALES Y ASIMILACION DE ESTRATEGIAS EN PROBLEMAS DE DESCUBRIMIENTO  

Microsoft Academic Search

* En la solución d e un p roblema, Davison, Deuser, & Sternberg (1994) señalan como procesos metacognitivos la identificación d el problema, la representación mental del problema, la planeación d e procedimientos y la evaluación del conocimiento a cerca del desempeño. Si en el ambiente de la tarea se le agregan activadores de juicios sobre valoraciones de dificultad, tiempo

DAVID MACÍAS; JAIME IBAÑEZ; NEREY ORTEGA

13

Aplicación del cálculo de las diferencias al problema del efecto de embalse  

Microsoft Academic Search

Resumen Presentamos una solución numérica del problema del efecto de embalse con ayuda de una ecuación lineal inhomogénea en diferencias finitas de primer orden, suponiendo una ley lineal del desagüe. Este método numérico es de maneje cómodo para un cálculo aproximado.

Hans Ertel

1962-01-01

14

Un Juego de Gravedad con Reconocimiento de Voz para Niños con Problemas de Lenguaje  

Microsoft Academic Search

En este trabajo presentamos un juego electrónico (Gravedad) con reconocimiento de voz para estimular a niños en edad escolar con problemas del lenguaje dislalia. Se presenta las características y elementos del juego electrónico, así como su integración con el sistema de reconocimiento de voz y los resultados de unas pruebas de usabilidad. El juego de Gravedad se desarrolló utilizando el

Carlos Miranda-Palm; Reyna Camal-U; José Cen-Magaña; Cinhtia Gonzalez-Segura; Sergio Gonzalez-Segura; Michel García; Lizzie Narvaez-Díaz

15

El desarrollo de la creatividad a través del proceso docente como problema social  

Microsoft Academic Search

El artículo tiene como propósito reflejar aspectos sobre el desarrollo de la creatividad en estudiantes de Educación Inicial del Programa Nacional de Formación de Educadores y Educadoras (PNFE). En tal sentido el Problema científico es ¿Cómo perfeccionar los modos de actuación en los estudiantes del PNFE? El Objetivo está dirigido a la Elaboración de una metodología para favorecer el desarrollo

Magaly Sarmiento Romero

2011-01-01

16

Gerenciamento de riscos na prática ortodôntica: como se proteger de eventuais problemas legais  

Microsoft Academic Search

Introdução: A relação profissional-paciente na área de Ortodontia e Ortopedia facial é bas- tante desgastante face à longa duração dos tratamentos e, por causa disso, muitas vezes essa relação pode se deteriorar trazendo prejuízos a ambas as partes. Objetivo: Este trabalho visa informar o leitor, em linguagem acessível, sobre os principais problemas jurídicos que podem envolver o ortodontista em sua

Ricardo Machado Cruz; Carla Pádua

2008-01-01

17

Habilidades Sociais e Problemas de Comportamento de Pré- Escolares: Comparando Avaliações de Mães e de Professoras Preschooler's Social Skills and Behavior Problems: Comparison between Mother and Teacher Assessments  

Microsoft Academic Search

Resumo Este estudo comparou avaliações de mães e professoras, sobre habilidades sociais e problemas de comportamento de crianças, identificadas pelas professoras, como tendo problemas de comportamento. Participaram mães e professoras de 24 crianças com problemas de comportamento e 24 crianças indicadas como sendo socialmente habilidosas. Foram utilizados o Questionário de Comportamentos Socialmente Adequados e a Escala Comportamental Infantil, versões para

Alessandra Turini Bolsoni-Silva; Edna Maria Marturano; Verônica Aparecida Pereira; Jair Wagner de Souza Manfrinato

18

Um Infixation and Prefixation in Toba Batak.  

ERIC Educational Resources Information Center

Examines the behavior of the morpheme, um, in Toba Batak and Tagalog, which alternates as a prefix or an infix, arguing that the variation is conditioned by constraints on consonant clusters. Three patterns of variation that occur with um are described, noting that the stages involved in changing from infixed to prefixed positions over time are…

Crowhurst, Megan J.

1998-01-01

19

Using uh and um in spontaneous speaking  

Microsoft Academic Search

Abstract: The proposal examined here is that speakers use uh and um to announce that they are initiatingwhat they expect to be a minor (uh), or major (um), delay in speaking. Speakers can use theseannouncements in turn to implicate, for example, that they are searching for a word, are decidingwhat to say next, want to keep the floor, or want

Herbert H. Clark; Jean E. Fox Tree

2002-01-01

20

Um supressor de fundo térmico para a câmara infravermelha CamIV  

NASA Astrophysics Data System (ADS)

O ângulo sólido subtendido pelos pixels na câmara infravermelha do NexGal (CamIV) que operamos no OPD/LNA contém contribuições provenientes do sistema de coleta de fluxo propriamente dito - sendo esta a parte que interessa para as medidas astronômicas - e contribuições da obstrução central, sistema de suporte do espelho secundário e região exterior à pupila de entrada do telescópio. Estas últimas contribuições são devi-das à emissão de corpo negro à temperatura ambiente e aumentam exponencialmente para comprimentos de onda maiores que 2 micra (banda K, no infravermelho próximo). Embora a resultante pode ser quantificada e subtraída dos sinais relevantes, sua variância se adiciona à variância do sinal, e pode ser facilmente a contribuição domi-nante para a incerteza final das medidas, tornando ineficiente o processo de extração de informação e degradando a sensibilidade da câmara. A maneira clássica de resolver esse problema em sistemas ópticos que operam no infravermelho, onde os efeitos da emissão térmica do ambiente são importantes, é restringir o ângulo sólido subtendido pelos pixels individuais exclusivamente aos raios provenientes do sistema óptico. Para tanto, projeta-se uma imagem real, bastante reduzida, da pupila de entrada do sistema óptico num anteparo que transmita para o sistema de imageamento só o que interessa, bloqueando as contribuições das bordas externas à pupila de entrada, obstrução central do telescópio e sistema de suporte. Como a projeção é realizada em ambiente criogênico, a contribuição térmica espúria é efetivamente eliminada. Nós optamos por um sistema do tipo Offner para implementar na prática esta função. Trata-se de um sistema baseado em espelhos esféricos, bastante compacto e ajustado por construção. A opção por espelhos do mesmo material que o sistema de suporte (Alumínio) minimiza a dilatação diferencial, crítica nesse tipo de aplicação. Apresentamos as soluções detalhadas do projeto óptico-mecânico, bem como uma análise de flexões e desempenho em termos de qualidade de imagem.

Jablonski, F.; Laporte, R.

2003-08-01

21

Survey of PAH Emission, 10-19.5 um  

NASA Astrophysics Data System (ADS)

A survey of the emission bands in the region 10-19.5 um, in planetary nebulae, proto-planetary objects, YSOs/HII regions, and related sources. The study will focus on the emission band at 16.4 um, attributed to PAHs, and will include the plateau of emission that extends from 15 um to the long wavelength limit of the Short-High IRS module.

Cruikshank, Dale; Sellgren, Kris

2004-09-01

22

Resolución de problemas basada en el análisis. Hacer del análisis y del razonamiento el foco de la enseñanza de la física  

Microsoft Academic Search

Resumen. Usando los resultados provenientes de la investigación educativa en áreas tales como concepciones alternativas, diferencias entre expertos y novatos, adquisición de esquemas, sobrecarga cognitiva y análisis jerárquico, hemos desarrollado un marco para pensar sobre la organización del conocimiento y su uso para la comunicación, y sobre el razonamiento y la resolución de problemas. Basados en este marco y en

J. Leonard William; William J. Gerace; Robert J. Dufresne

2002-01-01

23

Uh and Um Revisited: Are They Interjections for Signaling Delay?  

Microsoft Academic Search

Clark and Fox Tree (2002) have presented empirical evidence, based primarily on the London–Lund corpus (LL; Svartvik & Quirk, 1980), that the fillers uh and um are conventional English words that signal a speaker’s intention to initiate a minor and a major delay, respectively. We present here empirical analyses of uh and um and of silent pauses (delays) immediately following

Daniel C. O’Connell; Sabine Kowal

2005-01-01

24

"Uh" and "Um" Revisited: Are They Interjections for Signaling Delay?  

ERIC Educational Resources Information Center

Clark and Fox Tree (2002) have presented empirical evidence, based primarily on the London-Lund corpus (LL; Svartvik & Quirk, 1980), that the fillers "uh" and "um" are conventional English words that signal a speaker's intention to initiate a minor and a major delay, respectively. We present here empirical analyses of "uh" and "um" and of silent…

O'Connell, Daniel C.; Kowal, Sabine

2005-01-01

25

EVP2D- um programa automatico para a analise elastovistoplastica e de dano de problemas bidimensionais e axissimetricos. (EVP2D- a computer code developed for the eslastoviscoplastic-damage analysis of axyssimetrical and two-dimensional problems).  

National Technical Information Service (NTIS)

This work aims to describe the computer code EVP2D developed for the elastoviscoplastic-damage analysis of metallic components, with particular emphasis dedicated to the problem of creep damage and rupture. After a brief introduction of the basic concepts...

O. J. A. Goncalves Filho

1987-01-01

26

Il problema del litio.  

NASA Astrophysics Data System (ADS)

Contents: 1. Introduzione. 2. La nucleosintesi del Big Bang. 3. Il litio nelle stelle di popolazione II. 4. I modelli stellari standard. 5. Il litio negli ammassi aperti. 6. Meccanismi di distruzione "non standard". 7. I modelli non-standard applicati alla popolazione II. 8. L'evoluzione Galattica del litio. 9. Quali stelle producono litio? 10. Il litio come elemento chiave per dare un nome agli oggetti stellari più minuscoli. 11. Conclusioni.

D'Antona, F.

1995-03-01

27

A PRODUÇÃO IMAGINÁRIA DE ADOLESCENTES ANORÉXICAS E A APOLOGIA A UM NOVO ESTILO DE VIDA  

Microsoft Academic Search

Resumo: A anorexia é um transtorno no comportamento alimentar com impactos na imagem corporal. O objetivo deste estudo foi o de identificar o universo imaginário das adolescentes anoréxicas através da análise do discurso de sites de relacionamentos que fazem apologia à anorexia como um novo estilo de vida. Também foi aplicado um questionário a um pai, cuja filha faleceu em

Rafael da Silva Mattos; Gisela de Assis Conceição; Jeferson José Moebus Retondar

28

Universal Monitor (UM) for OTEC compact heat exchangers  

SciTech Connect

Universal Monitor (UM), is a device-independent concept to measure, with precision, the initiation and progression of fouling in any given OTEC Compact Heat Exchanger model with or without the application of countermeasures. Design description and supporting analyses for the Universal Monitor for OTEC Compact Heat Exchangers are presented.

Kuzay, T.M.

1981-09-01

29

Modernização Agrícola Francesa: a construção de um modelo analítico  

Microsoft Academic Search

Este artigo investiga o processo de modernização agrícola na França por meio das interpretações dos economistas, dos sociólogos e dos cientistas políticos, envolvendo especialmente o debate da sociologia e da economia rural contemporâneas. O objetivo é compreender a sua dinâmica específica pelo cruzamento entre diferentes áreas das Ciências Sociais com o intuito de construir um modelo interpretativo para a análise

Angelica Massuquetti

2008-01-01

30

CNN-UM based transversely isotropic elastic wave propagation simulation  

Microsoft Academic Search

Several previous studies have proved the effectiveness of the CNN-UM solution of isotropic elastic wave equations. Most crustal rocks of interest to exploration geophysics are either inherently anisotropic or behave as anisotropic materials when probed by seismic waves. This paper describes modeling of wave propagation in transversely isotropic media. Numerical methods which are based on finite-difference (FD) techniques (in time

Péter Sonkoly; István Noé; J. M. Carcione; Zoltán Nagy; Péter Szolgay

2007-01-01

31

FERUS: Um Ambiente de Desenvolvimento de Especica c~ oes CASL  

Microsoft Academic Search

Este artigo apresenta FERUS (Apoio Formal a Especic a c~ ao e Re-Utiliza c~ ao de Software), um am- biente desenvolvido no Departamento de Inform atica e Matem atica Aplicada da UFRN em parceria com o LORIA (Fran ca), que permite a cria c~ ao, manipula c~ ao e prototipa c~ ao de especic a c~ oes na linguagem CASL.

Gleydson Lima; Anamaria Martins; David Pereira; Demostenes Sen; Jorgiano Vidal

32

emancipação CIDADANIA FEMININA: UM LONGO E TORTUOSO CAMINHO  

Microsoft Academic Search

RESUMO: O presente trabalho tem a finalidade de discutir a questão da cidadania no contexto de gênero no feminino, diante do Estado e de uma sociedade que têm como princípios um viés masculino, que implica múltiplas exclusões além do privado - como excluir as mulheres dos aspectos políticos, sociais e econômicos - , limitações e privações políticas, econômicas e sociais.

Walfrido Nunes de Menezes

33

The International Space Station Urine Monitoring System (UMS)  

NASA Technical Reports Server (NTRS)

A device capable of making in-flight volume measurements of single void urine samples, the Urine Monitoring System (UMS), was developed and flown on seven U.S. Space Shuttle missions. This device provided volume data for each urine void from multiple crewmembers and allowed samples of each to be taken and returned to Earth for post-flight analysis. There were a number of design flaws in the original instrument including the presence of liquid carry-over producing invalid "actual" micturition volumes and cross-contamination between successive users from residual urine in "dead" spots". Additionally, high or low volume voids could not be accurately measured, the on-orbit calibration and nominal use sequence was time intensive, and the unit had to be returned and disassembled to retrieve the volume data. These problems have been resolved in a new version, the International Space Station (ISS) UMS, that has been designed to provide real-time in-flight volume data with accuracy and precision equivalent to measurements made on Earth and the ability to provide urine samples that are unadulterated by the device. Originally conceived to be interfaced with a U.S.-built Waste Collection System (WCS), the unit now has been modified to interface with the Russian-supplied Sanitary Hygiene Device (ASY). The ISS UMS provides significant advantages over the current method of collecting urine samples into Urine Collection Devices (UCDs), from which samples are removed and returned to Earth for analyses. A significant future advantage of the UMS is that it can provide an interface to analytical instrumentation that will allow real-time measurement of urine bioanalytes allowing monitoring of crewmember health status during flight and the ability to provide medical interventions based on the results of these measurements. Currently, the ISS UMS is scheduled to launch along with Node-3 on STS-130 (20A) in December 2009. UMS will be installed and scientific/functional verification completed prior to placing the instrument into operation. Samples collected during the verification sequence will be returned for analyses on STS-131 (19A) currently scheduled for launch in March 2010. The presence of a UMS on ISS will provide the capability to conduct additional collaborative human life science investigations among the ISS International Partners.

Feeback, Daniel L.; Cibuzar, Branelle R.; Milstead, Jeffery R.; Pietrzyk,, Robert A.; Clark, Mark S.F.

2009-01-01

34

Adaptive infrared image enhancement algorithm based on improved UM technique  

NASA Astrophysics Data System (ADS)

Infrared image enhancement is an important problem of infrared image processing. It gives rise to noise amplification in smooth areas and excessive overshoot in detail areas in the process of classical UM(unsharp masking) algorithm for infrared image enhancement. Aiming at above drawbacks, an adaptive method based on improved UM algorithm for infrared image enhancement is proposed in the paper. Our approach employs an adaptive Gauss-Newton filter to adjust the contrast enhancement parameters in different local areas, making sure that medium-contrast details are enhanced as well as large-contrast details in the process of contrast enhancement, and avoiding noise amplification, detail sharpening distortion and margin overshoot. Experiments show that the algorithm proposed in the paper is effective to improve the SNR and enhance the details of infrared image.

Wang, Xin-Sai; Wu, Qiang; Wang, Wei-Ping; He, Ming; Liu, Yu

2011-06-01

35

Spitzer\\/IRS spectroscopy of the 12um Seyferts  

Microsoft Academic Search

The extended 12um galaxy sample is a flux-limited sample of 893 galaxies selected from the IRAS Faint Source Catalog 2. A total of 118 objects from this sample have been classified optically as Seyfert galaxies, providing one of the largest infrared selected unbiased sample of active galactic nuclei (AGN). We present our prelimary results from our analysis of mid-infrared Spitzer\\/IRS

Yanling Wu; V. Charmandaris; J. Huang; J. Houck

2009-01-01

36

Paraganglioma RetroPeritoneal: Um diagnóstico raro mas importante  

Microsoft Academic Search

Os paragangliomas, tal como os feocromocitomas, sªo tumores das cØlulas cromafins do sistema neuroendÛcrino, secretores de catecolaminas. Diferem dos segundos pela sua localizaÁªo extra-adrenal. TŒm uma rara incidŒncia com cerca de 1 a 2\\/1.000.000. Os autores apresentam o caso de um jovem do sexo masculino, de 20 anos de idade, com crises hipertensivas paroxisticas com 2 anos de evoluÁªo, em

Manuel Castanheira de Oliveira; Gomes da Silva; Rui Machado; Olinda Lima; Ricardo Ramires; Filinto Marcelo

37

STS-40 Exp. No. 192 urine monitoring system (UMS) on OV-102's middeck  

NASA Technical Reports Server (NTRS)

STS-40 Experiment No. 192, Fluid-Electrolyte Regulation During Space Flight, urine monitoring system (UMS) is set up on the middeck of Columbia, Orbiter Vehicle (OV) 102, at the side hatch. The UMS is attached to OV-102's waste collection system (WCS). The urine specimen tray with sample tubes appears to the right of the UMS equipment.

1991-01-01

38

Resultados do desenvolvimento de um propulsor à plasma no Brasil  

NASA Astrophysics Data System (ADS)

Uma das partes mais importantes de um satélite é o controle de atitude do mesmo. E se tratando de um satélite científico, a atenção para este sistema deve ser redobrada. Uma possibilidade atraente para executar esta tarefa é a propulsão elétrica. Aqui, mostraremos resultados obtidos pelo propulsor à plasma PHALL-01, desenvolvido na Universidade de Brasília entre 2000 e 2003. Este é derivado do propulsor russo SPT-100 (Stationary Plasma Thruster), mas com o emprego inovador de um arranjo de imãs permanentes como fonte do campo magnético, este último o agente da aceleração do plasma. Esta alteração foi motivada pelo objetivo de que o mesmo operasse com o mínimo de potência elétrica. A partir da formulação teórica do mecanismo de aceleração, tendo como base as equações da magnetohidrodinâmica, pode-se obter vínculos sob os quais o propulsor pudesse ser construído. O mais forte destes é o que dita a topologia do campo magnético. Sendo assim, foram realizadas simulações computacionais, que definiram a geometria do propulsor. Após construído, este foi diagnosticado usando-se sondas de Langmuir e analisadores de energia. Como resultados, obtivemos a distribuição espacial da temperatura, densidade e potencial do plasma, bem como a distribuição angular do feixe produzido pelo mesmo em vários regimes de operação. O espectro de energia do feixe de plasma também foi medido, indicando íons de até 560eV. Combinando estes resultados, calculou-se o empuxo do propulsor: 84mN; e o impulso específico: 1083s. Estes demonstram que o mesmo estará qualificado, num futuro próximo, para o emprego no controle de atitude de satélites científicos, ou até mesmo como parte do conjunto propulsor primário, responsáveis pela transferência de órbitas.

Ferreira, I. S.; Ferreira, J. L.

2003-08-01

39

HD 208905: um sistema múltiplo de estrelas quentes  

NASA Astrophysics Data System (ADS)

Durante o survey de associações OB do disco Galáctico, foi constatada a multiplicidade do sistema HD 208905, pertencentes à associação de Cep OB2. Este objeto está classificado como uma estrela pertencente a um sistema múltiplo, com magnitude mv = 7.0 e tipo espectral B1V. De fato, os espectros de HD 208905 apresentam perfis de absorção triplicados. Dois dos perfis são bastante similares entre si, e são estreitos e bem definidos, sugerindo que as velocidades rotacionais projetadas (v sin i) das duas estrelas são baixas. Os espectros obtidos também apresentam perfis mais alargados que poderiam ser atribuídos a uma terceira componente estelar com v sin i mais alto. A análise de HD 208905 é baseada no estudo da variação da posição relativa dos perfis espectrais de acordo com a fase do sistema. Nossos dados observacionais são um conjunto de espectros de alta resolução obtidos no McDonald Observatory (Universidade do Texas, Austin), Kitt Peak National Observatory e Palomar Observatory, cobrindo o período de 10/91 até 12/95. Inicialmente, calculamos a velocidade radial de cada componente do sistema, considerando o desvio Doppler sofrido por cada estrela. As velocidades radiais medidas foram, em seguida, corrigidas para velocidades radiais heliocêntricas. O passo seguinte constituiu na determinação da periodicidade da série temporal definida pelas medidas das velocidades radiais heliocêntricas através da análise de Fourier. A nossa base de dados não permitiu definir uma solução única para o sistema HD 208905. As possíveis soluções encontradas têm períodos entre 1 e 27 dias e serão apresentadas e discutidas.

Candeias, J. P.; Daflon, S.; Cunha, K.

2003-08-01

40

17.5um thin Cu wire bonding for fragile low-K wafer technology  

Microsoft Academic Search

This paper describes the challenges of a 17.5um thin bare Cu wire bonding on aluminum bond pads for a fragile low-k wafer technology, on a BGA package. Previous evaluations have so far focused on 20um and 25um bare Cu wires as a suitable low cost replacement for Au wires. To improve performance, more fragile low-k wafer technology is being developed.

Teo Chen; Kim Jude

2010-01-01

41

An alternative proof of the universality of the CNN-UM and its practical applications  

Microsoft Academic Search

In this paper we give a proof of the universality of the Cellular Neural Network - Universal Machine (CNN-UM) alternative to those presented so far. On the one hand, this allows to find a general structure for CNN-UM programs; on the other hand, it helps to formally demonstrate that machine learning techniques can be used to find CNN-UM programs automatically.

Giovanni Egidio Pazienza; X. Vilasis-Cardona; R. Poli

2008-01-01

42

The UM/CTIO Magellanic Cloud Emission-line Survey  

NASA Astrophysics Data System (ADS)

The interstellar medium (ISM) is no longer thought to be a quiescent distribution of gas, but rather a dynamic and complex interaction of the ambient gas and dust with stellar winds, HII regions, planetary nebulae (PNe), supernovae (SNe), supernova remnants (SNRs), superbubbles, and gigantic supershells. Nowhere is this more apparent than in images of the ionized gas in the Magellanic Clouds. Their relative proximity and low extinction make them the ideal laboratories in which to study the ionized component of the ISM, its constituents, its energetics, and its interaction with the underlying stellar populations. We have begun an optical emission-line survey of these two nearby galaxies, the UM/CTIO Magellanic Cloud Emission-line Survey (MCELS). Together with parallel surveys at other wavelengths, it will provide the foundation upon which to build a deeper understanding of the ISM in the Clouds (and other galaxies), from small scales (~ 1 pc) to global scales. Taking advantage of the wide field of view of the UM/CTIO Curtis Schmidt telescope coupled to the sensitivity and large area of a STIS 2K CCD, we will obtain H alpha, [S II], and [O III] images of the central 8x8 degrees of the Large Magellanic Cloud and of the central 3.5 x 4.5 degrees of the Small Magellanic Cloud, covering most of the gaseous extent of both Clouds with a resolution of ~ 4". Survey observations began in November 1995, and we have completed approximately 75% of the imaging as of the end of the 1997/1998 Cloud season. The survey will provide definitive samples of wind-blown bubbles, PNe, and SNRs, as well as detailed and calibrated emission-line observations of HII regions, superbubbles, and supergiant shells. We will discuss the scientific objectives of the survey, describe the survey parameters and strategies, and present some of the recent results from analysis of preliminary datasets. Furthermore, we will describe the plans for making the digital Emission-line Atlas of the Magellanic Clouds publically available, providing a rich, homogeneous dataset to serve as the groundwork for further investigations into all aspects of the ISM, well beyond the scope of our own work.

Smith, R. C.; MCELS Team

43

Usina de ciências: um espaço pedagógico para aprendizagens múltiplas  

NASA Astrophysics Data System (ADS)

Entendemos que o Ensino de Astronomia é especialmente apropriado para motivar os alunos e aprofundar conteúdos em diversas áreas do conhecimento, pois envolve temas ligados à Física, Matemática, Química, Computação, Tratamento de Imagens e Instrumentação de Alta Precisão, além daqueles pertinentes as áreas de Geografia, História e Antropologia. Contudo, apesar do caráter interdisciplinar que esta ciência possui, a realidade atual é que a maioria dos professores em sala de aula não foram devidamente capacitados, durante o período de formação acadêmica, para ministrar conteúdos de Astronomia nos atuais Ensinos Fundamental e Médio. Neste trabalho, discutiremos de maneira ampla, num primeiro momento, a realidade do atual ensino de ciências praticado no Estado da Bahia, apontando por dependência administrativa, o crescimento e a redução do número de escolas, da taxa de analfabetismo por faixa etária, da escolarização, do atendimento, da aprovação, reprovação e abandono, de equipamentos e laboratórios e o grau de formação dos nossos atuais professores em pleno exercício de atividade docente. Num segundo momento, discutiremos o papel do Observatório Astronômico Antares/UEFS dentro desse contexto, ou seja, suas ações implementadas ao longo dos últimos anos e em particular, o recente projeto de extensão Ensino e Difusão de Astronomia, financiado pela Fundação Vitae, que procura traduzir no lúdico, no brincar de ciências, um espaço pedagógico para aprendizagens múltiplas. Neste, o papel do professor multiplicador associado ao laboratório de kits didáticos, de fácil construção e manipulação (alguns dos quais serão mostrados), perfazem os principais veículos para o desenvolvimento de conhecimentos, atitudes, habilidades e valores que preparam os nossos alunos para a carreira técnico-científica e para sua participação crítica e criativa na Sociedade.

Martin, V. A. F.; Poppe, P. C. R.; Orrico, A. C. P.; Pereira, M. G.

2003-08-01

44

New near-infrared observations and lens-model constraints for UM673  

NASA Astrophysics Data System (ADS)

Aims: We performed a detailed photometric analysis of the lensed system UM673 (Q0142-100) and an analysis of the tentative lens models. Methods: High-resolution adaptive optics images of UM673 taken with the Subaru telescope in the H band were examined. We also analysed the J, H and K-band observational data of UM673 obtained with the 1.3 m telescope at the CTIO observatory. Results: We present photometry of quasar components A and B of UM673, the lens, and the nearby bright galaxy using H-band observational data obtained with the Subaru telescope. Based on the CTIO observations of UM673, we also present J- and H-band photometry and estimates of the J, H and K-band flux ratios between the two UM673 components in recent epochs. The near-infrared fluxes of the A and B components of UM673 and their published optical fluxes are analysed to measure extinction properties of the lensing galaxy. We estimate the extinction-corrected flux ratio between components A and B to be about 2.14 mag. We discuss lens models for the UM673 system constrained with the positions of the UM673 components, their flux ratio, and the previously measured time delay. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.The final reduced Subaru images presented in Figs. 1 and 2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/566/A36

Koptelova, E.; Chiueh, T.; Chen, W. P.; Chan, H. H.

2014-06-01

45

The UM/CTIO Magellanic Cloud Emission-line Survey  

NASA Astrophysics Data System (ADS)

The interstellar medium (ISM) is no longer thought to be a quiescent distribution of gas, but rather a dynamic and complex interaction of the ambient gas and dust with stellar winds, H ii regions, planetary nebulae (PNe), supernovae (SNe), supernova remnants (SNRs), superbubbles, and gigantic supershells. Nowhere is this more apparent than in the Magellanic Clouds. Their relative proximity and low extinction make them the ideal laboratories in which to study the ISM, its constituents, its energetics, and its interaction with the underlying stellar populations. We have begun an optical emission-line survey of these two nearby galaxies which, together with parallel surveys at other wavelengths, will provide the foundation upon which to build a deeper understanding of the ISM in the Clouds (and other galaxies), from small scales ( ~ 1 pc) to global scales. Taking advantage of the wide field of view of the UM/CTIO Curtis Schmidt telescope coupled to the sensitivity and large area of the newly available STIS 2K CCD, we will obtain H alpha, [S ii], and [O iii] images of the central 8(deg) x 8(deg) of the Large Magellanic Cloud and of the central 3.5(deg) x 4.5(deg) of the Small Magellanic Cloud, covering most of the gaseous extent of both Clouds. Survey observations began in November 1995, and we completed almost 30% of the imaging in the 1995-96 Cloud season. The survey will provide definitive samples of wind-blown bubbles, PNe, and SNRs, as well as detailed and calibrated emission-line observations of HII regions, superbubbles, and supergiant shells. We will discuss the scientific objectives of the survey, describe the survey parameters and strategies, and present some of the first images from the survey. Furthermore, we will describe the plans for making the digital Emission-line Atlas of the Magellanic Clouds publically available, providing a rich, homogeneous dataset to serve as the groundwork for further investigations into all aspects of the ISM, well beyond the scope of our own work.

Smith, R. C.; Bregman, J.; Chu, Y.-H.; Ciardullo, R.; Jacoby, G. H.; Kennicutt, R.; Oey, M. S.; Winkler, P. F.; Zaritsky, D.

1996-09-01

46

Reliability and clinical validity of UM-CIDI DSM-III-R generalized anxiety disorder  

Microsoft Academic Search

This is the first in a series of reports on the long-term test-retest reliability and procedural validity of the UM-CIDI, a modified version of the Composite International Diagnostic Interview used in the US National Comorbidity Survey (NCS). This report focuses on DSM-III-R Generalized Anxiety Disorder (GAD). The NCS administered the UM-CIDI to a nationally representative sample of 8098 respondents in

Hans-Ulrich Wittchen; Ronald C. Kessler; Shanyang Zhao; Jamie Abelson

1995-01-01

47

EFICIÊNCIA DE PRODUTOS ALCALINOS E ORGÂNICO NA IMOBILIZAÇÃO DE CADMIO PRESENTE EM UM RESÍDUO INDUSTRIAL  

Microsoft Academic Search

anos de funcionamento, despejou na água e no solo um resíduo perigoso contendo metais pesados, entre eles o cádmio. Para avaliar o potencial de inertização do Cd presente no resíduo da Ingá, foram utilizados produtos de reação alcalina e orgânica em diferentes proporções, visando um pH de equilíbrio de 6,0; 6,5 e 7,0. No decorrer do período de incubação, foi

ROSIANE SALES PINHEIRO; FAB IANA; SOARES DOS SANTOS; MÁRCIO OSVALDO; LIMA MAGALHÃES; CLARICE DE OLIVEIRA; NELSON MOURA BRASIL; AMARAL SOBRINHO

2004-01-01

48

Detection of rotavirus in children with acute gastroenteritis in Porto Velho, Rondonia, Brazil.  

PubMed

Rotavirus group A (RVA) infection was ascertained in 591 fecal samples from children 0 to 6 years old with acute gastroenteritis. The vaccination status was also verified in all 591 subjects, with 302 (51.0 % ± 4.0 %) participants fully vaccinated against rotavirus. Forty-two of the vaccinated children (13.9 % ± 3.9 %) tested positive for RVA infection. Of the 289 unvaccinated children (49.0 % ± 4.0 %), 61 (21.1 % ± 4.7 %) had stools positive for RVA. This study suggests that the proportion of acute diarrhea cases caused by rotavirus was low and that the incidence of rotavirus diarrhea decreased over the study period in both vaccinated and unvaccinated children. PMID:24158345

Sandra, C A; Estevam, G K; Penati, M; Soares, L A; Ferreira, R G; Orlandi, P P; Najla, B M

2014-05-01

49

Descoberta de um aglomerado estelar massivo associado a fonte IRAS 16177-5018  

NASA Astrophysics Data System (ADS)

Neste trabalho apresentamos a descoberta de um aglomerado de estrelas jovens e massivas embebido em uma região HII extensa associado com a fonte IRAS 16177-5018, que se apresenta invisível na faixa óptica do espectro eletromagnético, onde a extinção é da ordem de AV = 26 magnitudes. As observações foram feitas com a camera infravermelha (CamIV) do Laboratório Nacional de Astrofísica, Brasil, equipada com um detector Hawaii de HgCdTe de 1024´1024 pixel acoplada ao telescópio de 60 cm Boller & Chivens do IAG. A fotometria obtida a partir das imagens nas bandas J, H e K (filtro estreito) mostrou a presença de fontes com excesso de emissão no infravermelho em 2.2 mm, concentradas em uma área de aproximadamente um minuto de arco quadrado em torno da nebulosa na qual esta embebido o objeto identificado como a fonte IRAS. A fonte IRAS apresenta um índice espectral (entre 2.2 21.3 mm) a = d log(l Fl) / d log l = 4.78, característico de um objeto extremamente jovem com luminosidade bolométrica (obtida da integral da densidade de fluxo entre o infravermelho próximo (1.25mm) e o infravermelho distante (100mm)) de 2.8´105L¤, o qual corresponde a uma estrela da sequência principal de idade zero de cerca de 42 M¤. A partir do diagrama cor-magnitude foi possível classificar a maioria dos membros do aglomerado como estrelas massivas mais luminosas que tipo espectral B5.

Roman Lopes, A.; Abraham, Z.; Lépine, J. R. D.

2003-08-01

50

UM-PRS: An implementation of the procedural reasoning system for multirobot applications  

NASA Technical Reports Server (NTRS)

The Procedural Reasoning System (PRS) is used in applications where predetermined situations might arise. The UM-PRS provides a reasoning system that represents robotic applications even in unpredictable domains, such as the robotic reconnaissance task domain outlined here. UM-PRS incorporates a changing context, rather than relying solely on a prearranged plan. The UM-PRS here provides representation important in the reasoning and interface between a mission plan and the executable map of an outdoor vehicle that changes its behavior based on what it comes in contact with in its environment. PRS is thus used in the dynamic control of such a vehicle, providing the basis for coordinating the joint task of multiple robotic vehicles by the their individual observations and representation.

Lee, Jaeho; Huber, Marcus J.; Durfee, Edmund H.; Kenny, Patrick G.

1994-01-01

51

Evolution and Persistence of 5-um Hot Spots at the Galileo Probe entry Latitude  

NASA Technical Reports Server (NTRS)

We present a study on the longtudinal locations, morphology and evolution of the 5-um hot spots at 6.5 deg. N latitude (planetocentric), from an extensive IRTF-NSFCAM data set spanning more that 3 years, which includes the date of the Galileo Probe entry.

Fisher, B. M.

1997-01-01

52

WebAPSEE: Um Ambiente Livre e Flexível Para Gerência de Processos de Software1  

Microsoft Academic Search

This paper describes an open-source Flexible Environment for Software Development Process Management. Thus, it presents a process enactment scenario used by the NetBeans project in order show the main functionalities provided by the cited environment. Resumo. Este artigo descreve um Ambiente Flexível para Gerência de Processos de desenvolvimento de Software baseado em Software Livre. Para ilustrar as funcionalidades fornecidas pelo

Adailton Lima; Breno França; Heribert Schlebbe; Rodrigo Quites Reis; Carla Lima Reis

53

ACRITARCOS ANORMAIS: UM CASO TERATOLÓGICO NO LIMITE LLANDOVERY\\/WENLOCK NA BACIA DO AMAZONAS, BRASIL 1  

Microsoft Academic Search

2, 4 RESUMO: Acritarcos anormais são indivíduos portadores de anomalias morfológicas e que são encontrados em diversos níveis ao longo da série siluriana, mas particularmente abundantes dentro do limite Llandovery\\/Wenlock. São poucos os trabalhos que fazem referências a acritarcos anormais. Na primeira citação foi descrito um Veryhachium europaeum \\

MARIA ANTONIETA C. RODRIGUES; TEREZA REGINA M. CARDOSO

54

METHOD 100.2 - DETERMINATION OF ASBESTOS STRUCTURES OVER 10 UM IN LENGTH IN DRINKING WATER  

EPA Science Inventory

Water is collected in a polyethylene or glass container and shipped to the laboratory. nown aliquots of the sample are filtered through a 0.1 to 0.22 um pore mixed cellulose ester (MCE). arbon extraction replica is prepared from a portion of the filter and is examined in the TEM ...

55

Associação movimento solidário colméia : um espaço para o resgate da cidadania das mulheres  

Microsoft Academic Search

Este trabalho tem como objetivo apresentar dados de uma investigação que o Grupo de Pesquisa Sexualidade e Escola (GESE) da Fundação Universidade Federal do Rio Grande (FURG) vem realizando junto às integrantes da Associação Movimento Solidário Colméia. Foram realizados vários encontros que funcionaram como um espaço narrativo em que as mulheres participaram ouvindo, contando e contrapondo histórias e fatos de

Guiomar Freitas Soares

2008-01-01

56

Um Novo Método de Dimensionamento de Reforços de Pavimentos Flexíveis Considerando a Reflexão de Fendas  

Microsoft Academic Search

RESUMO No presente trabalho é proposto um método de dimensionamento de reforços de pavimentos flexíveis, considerando como critérios de ruína o aparecimento de fendas à superfície da camada de desgaste, resultantes da reflexão do fendilhamento existente nas camadas betuminosas do pavimento existente, bem como o fendilhamento por fadiga. O método proposto baseia-se no dimensionamento estrutural corrente, acrescido duma verificação do

Jorge C. Pais; Paulo A. A. Pereira

2000-01-01

57

Um Estudo sobre Técnicas de Aprendizado de Máquina aplicadas à Mineração de Dados  

Microsoft Academic Search

This paper presents a comparative study between the application of Artificial Neural Networks and the k-Means algorithm, for Data Mining. Such machine learning techniques are used as tools for data classification and clustering. The database used treats on a psychological experiment that analyses the human behavior based in a scale. Resumo. Este artigo apresenta um estudo comparativo entre a aplicação

Maicon de Brito; Denise Regina Pechmann

2007-01-01

58

Variability of the broad absorption lines in the QSO UM 232  

NASA Technical Reports Server (NTRS)

Low-resolution spectra of UM 232 taken in 1978, 1979, and 1988 at Lick Observatory are presented. Large changes in the Si IV lambda 1397, CIV lambda 1549, and Al III lambda 1857 broad absorption lines are apparent. The decrease in column density in all three ions and an observed brightening of the QSO suggests that these changes are due to an increase in the ionization level driven by an increase in the central source luminosity. This mechanism has been proposed by Smith and Penston to explain small changes in the absorption spectrum of the QSO 1246-057. The spectra of UM 232 show that the fractional decrease in optical depth is smaller at higher outflow velocies. The structure of the broad absorption-line region (BALR) is investigted by estimating an ionization parameter for each ion species as a function of velocity.

Barlow, Thomas A.; Junkkarinen, Vesa T.; Burbidge, E. Margaret

1989-01-01

59

Um Projeto de Intervenção nos Espaços de Exposições do Planetário do Parque do Ibirapuera  

NASA Astrophysics Data System (ADS)

Cada vez mais a humanidade, em sua imensa maioria, está alheia às próprias conquistas. A insatisfação com esta realidade tem levado muitos pesquisadores, instituições, empresas e governos a procurar formas alternativas de acompanhar e transmitir todo este acervo científico cultural à sociedade, buscando a melhoria da qualidade da divulgação científica e contribuindo para o processo de cultura e alfabetização científica. Não há tempo nem espaço nos limitados planos curriculares do ensino médio e mesmo nos programas de ensino que propiciem a cultura científica e o acompanhamento do vertiginoso progresso científico e tecnológico atual. Neste sentido, a educação formal escolar precisa ser complementada ou acrescida de uma educação informal, extra-escolar, que possa oferecer à sociedade o que a escola não pode oferecer. A interação do público com museus, feiras de ciências, planetários, exposições científicas e/ou culturais é de grande importância para a aquisição e difusão de conhecimentos relacionados ao mundo científico. Reconhecidamente como um modelo de alfabetização científica esses ambientes promovem uma interação social capaz de propiciar de forma efetiva uma melhor relação ensino-aprendizagem com o público. Partindo desta realidade a Universidade Cruzeiro do Sul e a Escola Municipal de Astronomia (EMA) vêm desenvolvendo um projeto de intervenção no espaço em torno do Planetário do Parque do Ibirapuera com o objetivo de se implantar um ambiente de aprendizagem motivador e desafiador que promova a popularização de conteúdos relacionados à astronomia, astrofísica e cosmologia. Busca-se, também, a aproximação e interação do público com exposições que estão sendo implementadas no planetário. Considerando que se trata de um projeto de mestrado em fase inicial o objetivo do presente trabalho é apresentar a concepção básica e os critérios que estão sendo utilizados do ponto de vista pedagógico para as indicações dos objetos e experimentos que serão expostos, procurando formas de construir, expor e apresen! tá-los d e maneira mais eficiente em termos de uma aprendizagem significativa. (Apoio: Fundação Vitae, CNPq)

Elias, D. S.; Amaral, L. H.; de Araújo, C. F., Jr.; Matsuura, O. T.; Voelzke, M. R.

2005-08-01

60

Um enfoque antropológico para o ensino de astronomia no nível médio  

NASA Astrophysics Data System (ADS)

Há uma enorme carência de materiais didático-pedagógicos em astronomia para professores do ensino médio, sobretudo materiais que explorem também aspectos humanísticos. A origem do Universo é um bom exemplo desta constatação central. Embora tal origem teve explicações culturais diversas, os professores não têm informações sobre isso e muito menos material que trabalhe diferentes visões de mundo e treinamento que os capacite a abordá-las devidamente. Conseqüentemente o ensino de astronomia costuma ser tecnicista e dissociado do aspecto humano que alimenta o grande interesse e curiosidade que esses temas despertam. Aqui apresentamos propostas visando contribuir para reverter esse quadro e trabalhamos distintas visões de Universo: espontâneas, autóctones e científicas. Desenvolvemos práticas, materiais instrucionais e textos para viabilizar a adoção de um enfoque antropológico para o ensino de astronomia no nível médio, no qual as culturas humanística e científica sejam integradas de uma maneira contextualizada e eficaz para aquele ensino. Estas propostas foram aplicadas em um curso de treinamento para professores da rede pública de diferentes disciplinas. A receptividade dos professores à abordagem proposta e os resultados alcançados foram muito estimulantes. Destes, destacamos: produção de roteiros de atividades; desenvolvimento de práticas didático-pedagógicas específicas (e.g., encenação de mitos; dança primordial guarani; "criação" de constelações e interpretações pluriculturais; etc.); e sugestões concretas para a efetiva realização de um ensino interdisciplinar contextualizado, onde questões cosmogônicas servem de mote para iniciar tal ensino. Discutimos estes resultados e como o enfoque adotado pode instrumentalizar os professores para leituras de mundo que incluem naturalmente aspectos culturais, sociais e históricos associados aos temas estudados. (PPGECNM/UFRN; PRONEX/FINEP; NUPA/USP; Temáticos/FAPESP)

Costa, G. B.; Jafelice, L. C.

2003-08-01

61

Um Processador Construtivista na Web para documentos anotados (PcWDa)  

Microsoft Academic Search

Resumo A notacao XML, cada vez mais, desempenha um papel im- portante na representacao textual da informacao estruturada ou semi- estruturada, sendo a norma mais vulgarizada para marcacao de do- cumentos. Torna-se por isso indispensavel a existencia de ferramentas que possibilitem desenvolver(editar e validar) eficientemente documen- tos XML. Neste artigo pretende-se discutir a especificacao e o desenvolvimento de uma dessas

Mariana Isabel Ferreira; Sandra Cristina Lopes; Pedro Rangel Henriques

62

Monolithic 28.3 THz thermal image sensor incorporating 0.18-um CMOS foundry  

Microsoft Academic Search

This paper presents a fully monolithic approach to the design and fabrication of THz CMOS image sensor operating at 28.3 THz using the mass-producible 0.18-um 1P6M CMOS foundry. The CMOS sensor consists of antenna-coupled transducer, linearly transforming the intercepted THz (terahertz) electromagnetic energy into voltage representation. The THz image sensor adopts PTAT (Proportional To Absolute Temperature) sensing circuit configuration. The

S. Yang; L. Su; I. Huang; C. Ting; C. C. Tzuang

2010-01-01

63

Isoalantolactone Inhibits UM-SCC-10A Cell Growth via Cell Cycle Arrest and Apoptosis Induction  

PubMed Central

Isoalantolactone is a sesquiterpene lactone compound isolated from the roots of Inula helenium L. Previous studies have demonstrated that isoalantolactone possesses antifungal, anti-bacterial, anti-helminthic and anti-proliferative properties in a variety of cells, but there are no studies concerning its effects on head and neck squamous cell carcinoma (HNSCC). In the present study, an MTT assay demonstrated that isoalantolactone has anti-proliferative activity against the HNSCC cell line (UM-SCC-10A). Immunostaining identified that this compound induced UM-SCC-10A cell apoptosis but not necrosis. To explain the molecular mechanisms underlying its effects, flow cytometry and western blot analysis showed that the apoptosis was associated with cell cycle arrest during the G1 phase, up-regulation of p53 and p21, and down-regulation of cyclin D. Furthermore, our results revealed that induction of apoptosis through a mitochondrial pathway led to up-regulation of pro-apoptotic protein expression (Bax), down-regulation of anti-apoptotic protein expression (Bcl-2), mitochondrial release of cytochrome c (Cyto c), reduction of mitochondrial membrane potential (MMP) and activation of caspase-3 (Casp-3). Involvement of the caspase apoptosis pathway was confirmed using caspase inhibitor Z-VAD-FMK pretreatment. Together, our findings suggest that isoalantolactone induced caspase-dependent apoptosis via a mitochondrial pathway and was associated with cell cycle arrest in the G1 phase in UM-SCC-10A cells. Therefore, isoalantolactone may become a potential drug for treating HNSCC.

Wu, Minjun; Zhang, Hua; Hu, Jiehua; Weng, Zhiyong; Li, Chenyuan; Li, Hong; Zhao, Yan; Mei, Xifan; Ren, Fu; Li, Lihua

2013-01-01

64

UM-EC-1, a New Hypodiploid Human Cell Line Derived from a Poorly Differentiated Endometrial Cancer1  

Microsoft Academic Search

The University of Michigan endomctrial carcinoma cell line UM-EC- 1 was derived from a poorly differentiated endometrial adenocarcinoma of a 66-yr-old white female. Cell cultures were started using both tumor expiants and a cell suspension obtained from collagenase-treated tumor tissue. The collagenase-derived cell suspension gave rise to monolayer cultures which grew rapidly from the outset. This subline of UM-EC-1 has

Seija E. Grenman; Daniel L. Van Dyke; Maria J. Worsham; Fernando del Rosario; James A. Roberts; Kenneth D. McClatchey; Donald R. Schwartz; V. Ramesh Babu; Thomas E. Carey

1988-01-01

65

Enfermedades neurológicas y problemas de atención  

Microsoft Academic Search

SUMMARY Attention is the capacity to select a particular stimulus of the set of an experience and in it to focus and to concentrate our interest. It is classified in passive and active. Their components are: selectivity, concentration, limit and facility to neglect. The upheavals of the attention are: distractibility, hipoprosexia, aprosexia, hiperprosexia and perseveration. The attention deficit disorder as

Sandra P. Mantilla

66

ESTADOS DE EXCEPCIÓN Y PROBLEMAS DE AGENCIA  

Microsoft Academic Search

In Venezuela in reflected the world tendency of inclu- ding to the human rights how an indispensable element for the consolidation of the State of Right. The present work to try to settle down as the declaration of excep- tion states exacerbates existent problems between the State and the citizens and between the government and the organs executioners, increased the

Úrsula Straka

67

The Prisoner Problem--A Generalization.  

ERIC Educational Resources Information Center

Presents a generalization to the classic prisoner problem, which is inherently interesting and has a solution within the reach of most high school mathematics students. Suggests the problem as a way to emphasize to students the final step in a problem-solver's tool kit, considering possible generalizations when a particular problem has been…

Gannon, Gerald E.; Martelli, Mario U.

2000-01-01

68

The UM-Dearborn Observatory: Variable-object Research from an Urban Site  

NASA Astrophysics Data System (ADS)

Since its construction in 2007, the UM-Dearborn Observatory has provided a valuable educational tool both for students at UM-Dearborn and our neighbor-institution the Henry Ford Community College, and for the public at-large. We have recently (Jan 2014) added a systematic long-term research program with our 0.4m main telescope, to photometrically monitor a number of bright variable objects, including X-ray binaries and chemically-peculiar metal-poor stars over long timescales. We ultimately envision assembling a photometric database of (at least) four-color photometry over years-decades (i.e., many hundreds of orbital timescales for close binaries), with the preponderance of datapoints taken by undergraduates. To conduct this program, we have had to overcome a number of site challenges, the solutions of which will be useful to many programs using small telescopes at urban sites. The 0.4m telescope lies on a shared building within UM-Dearborn's main Fairlane campus - i.e., is about 20 meters above sea level, near several sources of water vapor (including an active steam vent less than 15 meters away), experiences significant mechanical vibrations from other building functions, and lies about 6 miles from central Detroit, well within the Detroit-Ann Arbor conurbation. Observing conditions are thus highly variable, with 5 arcsecond seeing typical and significant transparency variations observed even during a clear night. Nevertheless, we are now able to make scientifically useful observations in a semi-automatic way, to which our chosen scientific niche is well-suited. We present here our solutions to these challenges, along with initial results from our ongoing monitoring program.

Clyne, Elisabeth; Clarkson, William I.; Rasmussen, Eric J; Bord, Donald J.; Dage, Kristen; Matzke, David; Swift, Carrie

2014-06-01

69

Uma Visão do Universo Segundo um Grupo de Alunos do Ensino Médio de São Paulo  

NASA Astrophysics Data System (ADS)

A astronomia, embora seja uma ciência popular, com inúmeras descobertas de interesse público, ainda é apresentada desconsiderando-se os aspectos históricos e científicos relacionados ao seu desenvolvimento, sendo geralmente veiculada nos meios de comunicação de maneira pouco esclarecedora e não raro com imprecisões. Neste trabalho analisou-se a concepção de um grupo de estudantes de Ensino Médio sobre conceitos de astronomia, visando identificar sua visão de mundo a respeito do Universo, envolvendo idéias sobre espaço e tempo. Para issso, foi aplicado um questionário em três escolas da grande São Paulo em um espaço amostral de 270 alunos. Constatou-se que, embora o ensino de astronomia esteja previsto nos PCNEM, os resultados obtidos na pesquisa mostram que há grande deficiência no conhecimento dos temas investigados. Nesse sentido, verificou-se que apenas 20% dos alunos eram capazes de relacionar a sucessão das semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra. Por outro lado, somente 23% dos alunos tinham noções das distâncias entre os objetos celestes próximos da Terra e 56% conseguiram relacionar o Big Bang com a origem do Universo. Finalmente, constatou-se que 37% reconheciam o ano-luz como uma unidade de distância e 60% reconheciam o Sol como sendo uma estrela. Apesar de 60% dos alunos indicarem que a escola é a principal fonte para aquisição dos conhecimentos de astronomia, conclui-se que seus conceitos nessa área ainda são inadequados, havendo necessidade de ampliação e aprimoramento da abordagem desses conteúdos nos ambientes escolares.

Elias, D. S.; Araújo, M.; Amaral, L. H.; Voelzke, M. R.; Araújo, M.

2005-08-01

70

Isoalantolactone inhibits UM-SCC-10A cell growth via cell cycle arrest and apoptosis induction.  

PubMed

Isoalantolactone is a sesquiterpene lactone compound isolated from the roots of Inula helenium L. Previous studies have demonstrated that isoalantolactone possesses antifungal, anti-bacterial, anti-helminthic and anti-proliferative properties in a variety of cells, but there are no studies concerning its effects on head and neck squamous cell carcinoma (HNSCC). In the present study, an MTT assay demonstrated that isoalantolactone has anti-proliferative activity against the HNSCC cell line (UM-SCC-10A). Immunostaining identified that this compound induced UM-SCC-10A cell apoptosis but not necrosis. To explain the molecular mechanisms underlying its effects, flow cytometry and western blot analysis showed that the apoptosis was associated with cell cycle arrest during the G1 phase, up-regulation of p53 and p21, and down-regulation of cyclin D. Furthermore, our results revealed that induction of apoptosis through a mitochondrial pathway led to up-regulation of pro-apoptotic protein expression (Bax), down-regulation of anti-apoptotic protein expression (Bcl-2), mitochondrial release of cytochrome c (Cyto c), reduction of mitochondrial membrane potential (MMP) and activation of caspase-3 (Casp-3). Involvement of the caspase apoptosis pathway was confirmed using caspase inhibitor Z-VAD-FMK pretreatment. Together, our findings suggest that isoalantolactone induced caspase-dependent apoptosis via a mitochondrial pathway and was associated with cell cycle arrest in the G1 phase in UM-SCC-10A cells. Therefore, isoalantolactone may become a potential drug for treating HNSCC. PMID:24098753

Wu, Minjun; Zhang, Hua; Hu, Jiehua; Weng, Zhiyong; Li, Chenyuan; Li, Hong; Zhao, Yan; Mei, Xifan; Ren, Fu; Li, Lihua

2013-01-01

71

Otimização de procedimento de manobra para indução de reentrada de um satélite retornável  

NASA Astrophysics Data System (ADS)

Veículos espaciais que retornam à Terra passam por regimes de velocidade e condições de vôo distintos. Estas diferenças dificultam sua concepção aerodinâmica e o planejamento de seu retorno. A partir de uma proposta de um veículo orbital retornável (satélite SARA, em desenvolvimento no IAE/CTA) para realização de experimentos científicos e tecnológicos em ambiente de baixa gravidade, surge a necessidade de realizarem-se estudos considerando-se os aspectos relativos à sua aerodinâmica. Após o lançamento, o veículo deve permanecer em órbita pelo tempo necessário para a condução de experimentos, sendo depois direcionado à Terra e recuperado em solo. A concepção aerodinâmica é de importância para o vôo em suas diversas fases e deve considerar aspectos relativos à estabilização Aerodinâmica e ao arrasto atmosférico, sendo este último de importância crucial na análise do aquecimento a ser enfrentado. A manobra de retorno inclui considerações sobre as condições atmosféricas e dinâmica de reentrada, devendo ser calculada de forma mais precisa possível. O trabalho proposto avalia estudos da dinâmica de vôo de um satélite recuperável considerando aspectos relativos à determinação orbital com GPS, técnica utilizada com sucesso na CONAE, e seu comportamento aerodinâmico em vôo balístico de retorno, com ênfase em sua fase de reentrada atmosférica. Busca-se otimizar a manobra de reentrada de tal forma que a utilização do sistema GPS garanta minimizar a área de impacto com o solo.

Schulz, W.; Suarez, M.

2003-08-01

72

Analysis of a surface-normal coupled-quantum-well modulator at 1.55 um  

NASA Astrophysics Data System (ADS)

We report on the design and analysis of a surface-normal coupled-quantum-well (CQW) electro-absorption modulator (EAM) using a simulation software APSYS. The modulator is designed as a p-i-n diode operating at 1.55 um, in which the CQW structure is composed of InGaAs-InAlAs. In this paper, detailed analysis of the internal device physics is investigated, which includes the transition energy and the square of the normalized overlap integrals between confined energy levels for electrons and holes. This analysis reveals the mechanisms in the device that are responsible for the redshift of the absorption spectra for achieving an operating wavelength at 1.55 um, which, in turn, provides researchers with insight in the high performance modulators design. The analysis also explains the dependence of the absorption spectra on wavelength and bias voltage. The simulation model self-consistently solves for wavefunctions and the corresponding quantum states energies and then used for absorption spectra calculations within the 2D/3D drift-diffusion framework.

Li, Z. Q.; Lam, Alfred K. M.; Li, Z. Simon

2006-03-01

73

Activation pathways of synovial T lymphocytes. Expression and function of the UM4D4/CDw60 antigen.  

PubMed Central

Accumulating evidence implicates a central role for synovial T cells in the pathogenesis of rheumatoid arthritis, but the activation pathways that drive proliferation and effector function of these cells are not known. We have recently generated a novel monoclonal antibody against a rheumatoid synovial T cell line that recognizes an antigen termed UM4D4 (CDw60). This antigen is expressed on a minority of peripheral blood T cells, and represents the surface component of a distinct pathway of human T cell activation. The current studies were performed to examine the expression and function of UM4D4 on T cells obtained from synovial fluid and synovial membranes of patients with rheumatoid arthritis and other forms of inflammatory joint disease. The UM4D4 antigen is expressed at high surface density on about three-fourths of synovial fluid T cells and on a small subset of synovial fluid natural killer cells; in synovial tissue it is present on more than 90% of T cells in lymphoid aggregates, and on approximately 50% of T cells in stromal infiltrates In addition, UM4D4 is expressed in synovial tissue on a previously undescribed population of HLA-DR/DP-negative non-T cells with a dendritic morphology. Anti-UM4D4 was co-mitogenic for both RA and non-RA synovial fluid mononuclear cells, and induced IL-2 receptor expression. The UM4D4/CDw60 antigen may represent a functional activation pathway for synovial compartment T cells, which could play an important role in the pathogenesis of inflammatory arthritis. Images

Fox, D A; Millard, J A; Kan, L; Zeldes, W S; Davis, W; Higgs, J; Emmrich, F; Kinne, R W

1990-01-01

74

RADIAÇÃO LUMINOSA E FOTOSSÍNTESE EM QUATRO ESPÉCIES LENHOSAS NO INTERIOR DE UM FRAGMENTO DE FLORESTA SECUNDÁRIA SEMIDECIDUAL  

Microsoft Academic Search

valiou-se a ocorrência de picos de radiação luminosa e a resposta fotossintética de espécies arbóreas em um fragmento de floresta secundária semidecidual, no domínio da Floresta Atlântica. Os três locais estudados apresentavam exposições das encostas e índice de área foliar diferentes. Os resultados mostraram que existe uma marcante variabilidade na intensidade de radiação luminosa no interior do fragmento devido à

José Eduardo; Macedo Pezzopane; Geraldo Gonçalves; Maria das Graças; Ferreira Reis; Sílvio Nolasco de Oliveira Neto; Pedro Higuchi

2003-01-01

75

Obstáculos e potencialidades à competitividade das MPEs de calçados da Paraíba- um estudo da cooperação do aprendizado e da inovação  

Microsoft Academic Search

O objetivo deste trabalho é avaliar os obstáculos e potencialidades das micro e pequenas empresas da Paraíba, através do estudo da cooperação, aprendizado e inovação. Essas empresas estão concentradas espacialmente nos Arranjos Produtivos Locais (APLs) de Campina Grande e de Patos, onde há uma diversidade de atores públicos e privados, além de uma base institucional relevante. Para tanto, utilizou-se um

Janaina da Silva Alves

76

"Um, I Can Tell You're Lying": Linguistic Markers of Deception versus Truth-Telling in Speech  

ERIC Educational Resources Information Center

Lying is a deliberate attempt to transmit messages that mislead others. Analysis of language behaviors holds great promise as an objective method of detecting deception. The current study reports on the frequency of use and acoustic nature of "um" and "like" during laboratory-elicited lying versus truth-telling. Results obtained using a…

Arciuli, Joanne; Mallard, David; Villar, Gina

2010-01-01

77

Origin and characteristics of yardangs in the Um Al-Rimam depressions (N Kuwait)  

NASA Astrophysics Data System (ADS)

Although Arabia hosts one of the largest deserts in the world, studies regarding aeolian erosional features in general and yardangs in particular are rare. The principal aim of this study is to delineate and investigate the various forms of yardangs in the Um Al-Rimam depressions in the northern part of Kuwait. The study area consists of two main depressions connected by neck area made up of continental sediments. Both depressions are surrounded by a dissected escarpment and their floors host muddy playas. On lithological bases, three main types of yardang have been identified: 7 yardangs are sculptured in sandstones of Lower Fars Formation (Lower to Middle Miocene), 23 are carved in calcretic rocks of Ghar Formation (Oligocene to Lower Miocene), and 11 yardangs are developed in Quaternary sediments. Their mean orientation NW (297°) coincides with the prevailing direction of the strong local northwesterly wind called the shamal. The average length/width ratio is 1.5:1. The wide geographic distribution of yardangs around the margins of the northern depression is due to sand blasting. This is explained by the annual sand accumulation measured in the study area where the northern depression shows 143 times higher accumulation than the southern depression, the neck area and the platform above the depressions. Also, the field measurements for annual erosional rates show that the sides of the yardangs are more affected by erosion compared to their middle parts. Remarkably slight mineralogical variations were detected within the surface sediments of Um Al-Rimam depressions and the Quaternary muddy yardangs which indicate a common origin. The age of yardangs is unknown but annual erosional rates on a small Quaternary muddy yardang suggest that they range in age between 44 and 1500 years depending on yardang size. It is believed, as indicated from field observation and interpretation of aerial photos, that the majority of yardangs are pre-existing bedrock forms. These forms were developed by paleo-surface hydrological processes which were modified by wind action in latter phase.

Al-Dousari, Ali. M.; Al-Elaj, Maraheb; Al-Enezi, Eqbal; Al-Shareeda, Abdulaziz

2009-03-01

78

BUDDA (Bulge/Disk Decomposition Analysis) - um novo programa para análise estrutural de galáxias  

NASA Astrophysics Data System (ADS)

Tem sido prática comum nos últimos anos estudar a distribuição de luminosidade em galáxias fazendo uso da informação contida em toda a imagem da galáxia, já que esta técnica tem se mostrado muito mais confiável do que o simples ajuste de perfis radiais de luminosidade. Através destes estudos bidimensionais, melhores resultados tem sido obtidos na análise e.g. do Plano Fundamental, de correlações entre os parâmetros estruturais de galáxias, de sub-estruturas como barras e anéis nucleares etc. Apresentamos um novo código bidimensional, o BUDDA, de análise estrutural de galáxias, que será disponibilizado para a comunidade. Desenvolvido por nós, o código determina os parâmetros estruturais de galáxias de forma prática e robusta, e pode ser aplicado genericamente em qualquer estudo sobre a formação, evolução e estrutura de galáxias. O programa ainda permite a avaliação direta de sub-estruturas, através de imagens residuais que são obtidas ao se subtrair, das imagens originais, bojo e disco sintéticos que melhor representam essas componentes da galáxia sob consideração. Será apresentada a forma de utilização do código, bem como séries de testes que atestam a sua funcionalidade. Além disso, os resultados da aplicação do código em uma amostra de 51 galáxias serão expostos como exemplo prático, e do seu enorme potencial de uso.

Gadotti, D. A.; de Souza, R. E.; Dos Anjos, S.

2003-08-01

79

Determinação da massa de júpiter a partir das órbitas de seus satélites: um experimento didático  

NASA Astrophysics Data System (ADS)

Este trabalho apresenta o roteiro piloto de uma prática observacional em astronomia, junto com os primeiros resultados obtidos nesta fase de implementacão. O projeto, que será executado em duas etapas, visa introduzir noções de Astronomia a alunos do Ensino Médio e iniciantes nos cursos de Física. O experimento consiste em medir as órbitas dos satélites Galileanos e, a partir da análise dos dados coletados, verificar a validade da Lei das órbitas de Kepler, determinando a massa do planeta Júpiter. Em uma primeira etapa, as observações serão feitas utilizando um telescópio Meade LX200 10" e câmera CCD para obter uma seqüência de imagens do planeta, que possibilitará medir o movimento de seus satélites. A segunda etapa terá início a partir do funcionamento do telescópio em modo robótico, com a possibilidade de observações via internet por instituições de ensino. Para o desenvolvimento deste experimento foram inicialmente coletadas várias imagens de Júpiter obtidas com os instrumentos citados acima. Estas imagens serviram como base para confecção dos roteiros para a experiência no nível médio e superior. Os roteiros serão inicialmente apresentados em uma home-page. Nela também se buscará uma contextualização histórica da experiência bem como o estabelecimento de relações com professores e alunos, propostas metodológicas e a disponibilização dos programas computacionais necessários para a utilização "on-line" pelos usuários. O projeto conta com apoio da Fundação VITAE.

Schlickmann, M. S.; Saito, R. K.; Becker, D. A.; Rezende, M. F., Jr.; Cid Fernandes, R.

2003-08-01

80

Flux and color variations of the doubly imaged quasar UM673  

NASA Astrophysics Data System (ADS)

Aims: With the aim of characterizing the flux and color variations of the multiple components of the gravitationally lensed quasar UM673 as a function of time, we have performed multiepoch and multiband photometric observations with the Danish telescope at the La Silla Observatory. Methods: The observations were carried out in the VRi spectral bands during four seasons (2008-2011). We reduced the data using the point spread function photometric technique as well as aperture photometry. Results: Our results show for the brightest lensed component some significant decrease in flux between the first two seasons (+ 0.09/+ 0.11/+ 0.05 mag) and a subsequent increase during the following ones (- 0.11/- 0.11/- 0.10 mag) in the V/R/i spectral bands, respectively. Comparing our results with previous studies, we find smaller color variations between these seasons as compared with previous ones. We also separate the contribution of the lensing galaxy from that of the fainter and close lensed component. Based on data collected by MiNDSTEp with the Danish 1.54 m telescope at the ESO La Silla ObservatoryLight curves are only available in electronic from at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/551/A104

Ricci, D.; Elyiv, A.; Finet, F.; Wertz, O.; Alsubai, K.; Anguita, T.; Bozza, V.; Browne, P.; Burgdorf, M.; Calchi Novati, S.; Dodds, P.; Dominik, M.; Dreizler, S.; Gerner, T.; Glitrup, M.; Grundahl, F.; Hardis, S.; Harpsøe, K.; Hinse, T. C.; Hornstrup, A.; Hundertmark, M.; Jørgensen, U. G.; Kains, N.; Kerins, E.; Liebig, C.; Maier, G.; Mancini, L.; Masi, G.; Mathiasen, M.; Penny, M.; Proft, S.; Rahvar, S.; Scarpetta, G.; Sahu, K.; Schäfer, S.; Schönebeck, F.; Schmidt, R.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Thöne, C. C.; Wambsganss, J.; Zimmer, F.; Zub, M.; Surdej, J.

2013-03-01

81

Amiloidose sistêmica do tipo AA em um canino Shar-pei Chinês Systemic Amyloidosis type AA in a dog Chinese Shar-Pei  

Microsoft Academic Search

A deposição sistêmica do amilóide pode ocorrer de forma hereditária, a predisposição ocorre principalmente em gatos Abissínios e cães da raça Shar-pei Chinês. Um canino da raça Shar-pei Chinês foi encaminhado para necropsia no Setor de Patologia Veterinária da UFRGS. O canino apresentava aumento de volume dos membros posteriores e nos seus exames bioquímicos havia um aumento significativo de creatinina

Luciana Sonne; Eduardo Conceição de Oliveira; Adriana da Silva Santos; Saulo Petinatti Pavarini; Pedro Soares Bezerra Júnior; Nadia Aline; Bobbi Antoniassi; Jardel Pereira Tessari; David Driemeier

82

Petrology and geochemistry of the banded iron formation (BIF) of Wadi Karim and Um Anab, Eastern Desert, Egypt: Implications for the origin of Neoproterozoic BIF  

Microsoft Academic Search

Banded iron formation (BIF) is exposed among the Precambrian rocks in the Wadi Karim and Um Anab areas in the Eastern Desert of Egypt. The BIF conformably alternates with Neoproterozoic arc metavolcanic rocks, which comprise metabasalts and mafic to intermediate metapyroclastic rocks. The BIF of Wadi Karim belongs to the oxide and mixed carbonate-oxide facies, while that of Um Anab

Fawzy F. Basta; Ayman E. Maurice; Lluís Fontboté; Pierre-Yves Favarger

2011-01-01

83

Project UM-HAUL: A self-unloading reusable lunar lander  

NASA Astrophysics Data System (ADS)

The establishment of a lunar base is technologically and financially challenging. Given the necessary resources and political support, it can be done. In addition to the geopolitical obstacles, however, there are logistical problems involved in establishing such bases that can only be overcome with the acquisition of a significant transportation and communications network in the Earth-Moon spatial region. Considering the significant number of payloads that will be required in this process, the mass-specific cost of launching these payloads, and the added risk and cost of human presence in space, it is clearly desirable to automate major parts of such an operation. One very costly and time-consuming factor in this picture is the delivery of payloads to the Moon. Foreseeable payloads would include atmospheric modules, inflatable habitat kits, energy and oxygen plant elements, ground vehicles, laboratory modules, crew supplies, etc. The duration of high-risk human presence on the Moon could be greatly reduced if all such payloads were delivered to the prospective base site in advance of crew arrival. In this view, the idea of a 'Self-Unloading Reusable Lunar Lander' (SURLL) arises naturally. The general scenario depicts the lander being brought to low lunar orbit (LLO) from Earth atop a generic Orbital Transfer Vehicle (OTV). From LLO, the lander shuttles payloads down to the lunar surface, where, by means of some resident, detachable unloading device, it deploys the payloads and returns to orbit. The general goal is for the system to perform with maximum payload capability, automation, and reliability, while also minimizing environmental hazards, servicing needs, and mission costs. Our response to this demand is UM-HAUL, or the UnManned Heavy pAyload Unloader and Lander. The complete study includes a system description, along with a preliminary cost analysis and a design status assessment.

84

The response of chemistry and climate to the 11-year solar cycle in UM-UKCA  

NASA Astrophysics Data System (ADS)

It is now generally agreed that the UV variability associated with the 11-year solar cycle leads to changes in ozone and temperature in the upper stratosphere. In addition, a range of observational and modelling studies suggest that such changes are the starting point for a chain of processes (including feedbacks) resulting in circulation changes in many areas of the atmosphere. However, precise details of the interactions between chemistry and meteorology induced by solar variability remain under question. In our study, we use a version of the UM-UKCA chemistry-climate model with consistent spectrally-resolved solar variability. While the solar cycle in heating rates has been applied with the method used in HadGEM2-ES, fine spectrally-resolved solar variability has been uniquely incorporated into the Fast-JX photolysis scheme. We perform two 50-year-long perpetual year solar maximum and solar minimum integrations and complement them with a three member ensemble of a transient 1960-2010 integration in which boundary conditions correspond by and large to the CCMI Ref-C1 scenario. We show how the inferred solar signals vary between the individual experiments. This indicates high natural variability and the resulting contamination of the solar signal with contributions from other processes as well as the existence of possible non-linearities between the solar cycle and other atmospheric forcings. Therefore, we highlight that long data series are needed to ensure correct attribution of the modelled and observed anomalies. In addition, we present results from two perpetual year experiments in which the solar cycle was applied exclusively in either short-wave heating or photolysis. We find large non-linearities in the modelled anomalies as compared to the realistic integration with both modulations included. This highlights the subtle nature of the dynamical response to the solar cycle forcing and indicates the need for interactive chemistry with a detailed photolysis scheme for modelling the solar-climate interactions fully.

Bednarz, Ewa; Telford, Paul; Maycock, Amanda; Abraham, Luke; Braesicke, Peter; Pyle, John

2014-05-01

85

A tri-mode 802.11 baseband PHY mixed signal integrated circuit in 0.13-um CMOS  

NASA Astrophysics Data System (ADS)

A 0.13um CMOS mixed signal 802.11a/b/g baseband PHY IC, with per-packet receive diversity, 802.11h radar/DFS support and an MRC/MIMO coprocessor interface, is described. Required receive C/N is 5dB at 6 Mbps, and 20dB at 54 Mbps. Residual packet error rate is less than 4% for 54 Mbps and 0.1% for 6 Mbps link data rates in a 50ns delay spread channel. The 4.75×4.75mm chip, fabricated in 1P7M 0.13um CMOS, has 8M transistors and dissipates under 31mW in sleep, 206mW in Tx, and 362mW in Rx.

Ryan, Philip J.; Hart, Brian; Webb, Mike; Wong, Kevin

2004-03-01

86

Structural elements and incremental strain history of the basement rocks of Um Had area, central Eastern Desert, Egypt  

Microsoft Academic Search

The Um Had area, central Eastern Desert, Egypt shows a regional stretching in the NW–SE and a contraction in the NE–SW direction.\\u000a Major NW–SE folds, small recumbent folds, and local thrusts and reverse faults were recognized. Complicated relation between\\u000a folds and boudinage was identified. This stretching amount ranges from 1.282 to 1.309. Earlier coaxial and later non-coaxial\\u000a strains were inferred.

Ahmed Akawy

2009-01-01

87

Mapping propositional and multi-valued logic rule-based expert systems to the CNN-UM  

Microsoft Academic Search

An expert system usually requires a human expert to define rules which describe a law, what can be inferred from the observed or deduced facts by using simple 'if-then' structures. This paper presents four possible rule-based expert-system implementations in a CNN-UM (cellular neural network - universal machine) dichotomous production system, with a forward- or backward-chaining inference engine, and expert systems

Dávid Bálya

88

Far-ultraviolet spectroscopy of the quasar UM 675 with the faint object spectrograph on the Hubble Space Telescope  

NASA Technical Reports Server (NTRS)

To investigate the far-UV spectral properties of a QSO and to look for evidence of He I 584 A emission and absorption the Faint Object Spectrograph aboard the HST was used to observed UM 675. Light is detected down to 520 A in the object in the rest frame and limits are set to He I emission, the He I Gunn-Peterson effect at z = 2.148, and Ly-alpha absorption at z roughly 0.5.

Beaver, E. A.; Burbidge, E. M.; Cohen, Ross D.; Junkkarinen, Vesa T.; Lyons, Ronald W.

1991-01-01

89

Pan-African skarn deposits related to banded iron formation, Um Nar area, central Eastern Desert, Egypt  

Microsoft Academic Search

The Neoproterozoic Um Nar banded iron formation (BIF) is hosted in low to medium-grade, dominantly continental to submarine, metamorphosed sedimentary sequence. Geologic, mineral chemistry, fluid inclusion and geochemical studies suggest that Fe-skarns were developed during thermal, low-pressure regional metamorphism of calcareous-rich Neoproterozoic BIF. The skarn zone is identified by the presence of andradite, diopside, amphiboles and epidote, together with variable

Galal H El Habaak

2004-01-01

90

NE VIII lambda 774 and time variable associated absorption in the QSO UM 675  

NASA Technical Reports Server (NTRS)

We discuss measurements of Ne VIII lambda 774 absorption and the time variability of other lines in the z(sub a) approximately equal z(sub e) absorption system of the z(sub e) = 2.15 QSO UM 675 (0150-203). The C IV lambda 1549 and N V 1240 doublets at z(sub a) = 2.1340 (shifted approximately 1500 km/s from z(sub e) strengthened by a factor of approximately 3 between observations by Sargent, Boksenberg and Steidel (1981 November) and our earliest measurements (1990 November and December). We have no information on changes in other z(sub a) approximately equal z(sub e) absorption lines. Continued monitoring since 1990 November shows no clear changes in any of the absorptions between approximately 1100 and 1640 A rest. The short timescale of the variability (less than or approximately equal to 2.9 yr rest) strongly suggests that the clouds are dense, compact, close to the QSO, and photoionized by the QSO continuum. If the line variability is caused by changes in the ionization, the timescale requires densities greater than approximately 4000/cu cm. Photoionization calculations place the absorbing clouds within approximately 200 pc of the continuum source. The full range of line ionizations (from Ne VIII lambda 774 to C III lambda 977) in optically thin gas (no Lyman limit) implies that the absorbing regions span a factor of more than approximately 10 in distance or approximately 100 in density. Across these regions, the total hydrogen (H I + H II) column ranges from a few times 10(exp 18)/sq cm in the low-ionization gas to approximately 10(exp 20)/sq cm where the Ne VIII doublet forms. The metallicity is roughly solar or higher, with nitrogen possibly more enhanced by factors of a few. The clouds might contribute significant line emission if they nearly envelop the QSO. The presence of highly ionized Ne VIII lambda 774 absorption near the QSO supports recent studies that link z(sub a) approximately equal to z(sub e) systems with X-ray 'wamr absorbers. We show that the Ne VIII absorbing gas would itself produce measurable warm absorption -- characterized by bound-free O VII or O VIII edegs near 0.8 keV -- if the column densities were N(sub H) greater than or approximately equal to 10(exp 21)/sq cm (for solar abundances).

Hamann, Fred; Barlow, Thomas A.; Beaver, E. A.; Burbidge, E. M.; Cohen, Ross D.; Junkkarinen, Vesa; Lyons, R.

1995-01-01

91

On the Compact H II Galaxy UM 408 as Seen by GMOS-IFU: Physical Conditions  

NASA Astrophysics Data System (ADS)

We present Integral Field Unit GMOS-IFU data of the compact H II galaxy UM 408, obtained at the Gemini South telescope, in order to derive the spatial distribution of emission lines and line ratios, kinematics, plasma parameters, and oxygen abundances as well the integrated properties over an area of 3''×4farcs4 equivalent with ~750 pc × 1100 pc located in the central part of the galaxy. The starburst in this area is resolved into two giant regions of about 1farcs5 and 1'' (~375 and ~250 pc) diameter, respectively and separated 1.5-2'' (~500 pc). The extinction distribution concentrate its highest values close but not coincident with the maxima of H? emission around each one of the detected regions. This indicates that the dust has been displaced from the exciting clusters by the action of their stellar winds. The ages of these two regions, estimated using H? equivalent widths, suggest that they are coeval events of ~5 Myr with stellar masses of ~104 M sun. We have also used [O III]/H? and [S II]/H? ratio maps to explore the excitation mechanisms in this galaxy. Comparing the data points with theoretical diagnostic models, we found that all of them are consistent with excitation by photoionization by massive stars. The H? emission line was used to measure the radial velocity and velocity dispersion. The heliocentric radial velocity shows an apparent systemic motion where the east part of the galaxy is blueshifted, while the west part is redshifted, with a relative motion of ~10 km s-1. The velocity dispersion map shows supersonic values typical for extragalactic H II regions. We derived an integrated oxygen abundance of 12+log(O/H) = 7.87 summing over all spaxels in our field of view. An average value of 12+log(O/H) = 7.77 and a difference of ?(O/H) = 0.47 between the minimum and maximum values (7.58 ± 0.06-8.05 ± 0.04) were found, considering all data points where the oxygen abundance was measured. The spatial distribution of oxygen abundance does not show any significant gradient across the galaxy. On the other hand, the bulk of data points are lying in a region of ±2? dispersion (with ? = 0.1 dex) around the average value, confirming that this compact H II galaxy, like other previously studied dwarf irregular galaxies, is chemically homogeneous. Therefore, the new metals processed and injected by the current star formation episode are possibly not observed and reside in the hot gas phase, whereas the metals from previous events are well mixed and homogeneously distributed through the whole extent of the galaxy.

Lagos, Patricio; Telles, Eduardo; Muñoz-Tuñón, Casiana; Carrasco, Eleazar R.; Cuisinier, François; Tenorio-Tagle, Guillermo

2009-06-01

92

User's manual (UM) for the enhanced logistics intratheater support tool (ELIST) database utility segment version 8.1.0.0 for solaris 7.  

SciTech Connect

This document is the User's Manual (UM) for the Enhanced Logistics Intratheater Support Tool (ELIST) Database Utility Segment. It tells how to use its features to administer ELIST database user accounts.

Dritz, K.

2002-03-06

93

Imagens do céu ontem e hoje - um multimídia interativo de astronomia e uma nova exposição no MAST  

NASA Astrophysics Data System (ADS)

"Imagens do Céu Ontem e Hoje" é o título de uma nova exposição que está sendo inaugurada no Museu de Astronomia e Ciências Afins (MCT), que inclui experimentos interativos, maquetes, réplicas e 8 terminais de computador com um multimídia interativo sobre Astronomia para consulta dos visitantes. O multimídia apresenta um conteúdo bastante extenso, que engloba quase todos os temas em Astronomia, consistindo numa fonte de divulgação e pesquisa para um público que vai das crianças até estudantes universitários. O conteúdo está distribuído em mais de 500 páginas de texto divididas em 4 módulos: "O Universo", "Espectroscopia", "Telescópios" e "Observando o Céu". Cada módulo é subdividido em 5 seções, em média, cada uma iniciada por uma animação que ilustra os temas a serem abordados na seção. Ao final da animação, uma lista de temas é apresentada sob o título "Saiba Mais". Para exemplificar, o módulo "O Universo" contém as seguintes seções: "O Universo visto pelo homem", "Conhecendo o Sistema Solar", "Indo além do Sistema Solar", "Nossa Galáxia, a Via-Láctea" e "Indo mais além, a imensidão do Universo". A seção "Conhecendo o Sistema Solar", por sua vez, tem os seguintes temas: "A origem do Sistema Solar", "O Sol", "Os planetas", "Satélites, asteróides, cometas e outros bichos..." e "O Sistema Solar em números". Cada texto é repleto de imagens, quadros, desenhos, esquemas, etc, além de passatempos ao final de cada seção, incluindo jogos interativos, quadrinhos e curiosidades, que auxiliam o aprendizado de forma divertida. Apresentamos neste trabalho as idéias gerais que permearam a produção da exposição, e uma viagem pelo multimídia para exemplificar sua estrutura e conteúdo. O multimídia será posteriormente disponibilizado para o público externo pela página eletrônica do MAst e/ou por intermédio de uma publicação comercial.

Caretta, C. A.; Lima, F. P.; Requeijo, F.; Vieira, G. G.; Alves, F.; Valente, M. E. A.; de Almeida, R.; de Garcia, G. C.; Quixadá, A. C.

2003-08-01

94

Community Structure and Activity of a Highly Dynamic and Nutrient-Limited Hypersaline Microbial Mat in Um Alhool Sabkha, Qatar  

PubMed Central

The Um Alhool area in Qatar is a dynamic evaporative ecosystem that receives seawater from below as it is surrounded by sand dunes. We investigated the chemical composition, the microbial activity and biodiversity of the four main layers (L1–L4) in the photosynthetic mats. Chlorophyll a (Chl a) concentration and distribution (measured by HPLC and hyperspectral imaging, respectively), the phycocyanin distribution (scanned with hyperspectral imaging), oxygenic photosynthesis (determined by microsensor), and the abundance of photosynthetic microorganisms (from 16S and 18S rRNA sequencing) decreased with depth in the euphotic layer (L1). Incident irradiance exponentially attenuated in the same zone reaching 1% at 1.7-mm depth. Proteobacteria dominated all layers of the mat (24%–42% of the identified bacteria). Anoxygenic photosynthetic bacteria (dominated by Chloroflexus) were most abundant in the third red layer of the mat (L3), evidenced by the spectral signature of Bacteriochlorophyll as well as by sequencing. The deep, black layer (L4) was dominated by sulfate reducing bacteria belonging to the Deltaproteobacteria, which were responsible for high sulfate reduction rates (measured using 35S tracer). Members of Halobacteria were the dominant Archaea in all layers of the mat (92%–97%), whereas Nematodes were the main Eukaryotes (up to 87%). Primary productivity rates of Um Alhool mat were similar to those of other hypersaline microbial mats. However, sulfate reduction rates were relatively low, indicating that oxygenic respiration contributes more to organic material degradation than sulfate reduction, because of bioturbation. Although Um Alhool hypersaline mat is a nutrient-limited ecosystem, it is interestingly dynamic and phylogenetically highly diverse. All its components work in a highly efficient and synchronized way to compensate for the lack of nutrient supply provided during regular inundation periods.

Al-Thani, Roda; Al-Najjar, Mohammad A. A.; Al-Raei, Abdul Munem; Ferdelman, Tim; Thang, Nguyen M.; Shaikh, Ismail Al; Al-Ansi, Mehsin; de Beer, Dirk

2014-01-01

95

10.1: A 4 GSample\\/s 8b ADC in 0.35-um CMOS  

Microsoft Academic Search

A 4-GSample\\/s, 8-bit ADC dissipates 4.6 W in 0.35-um CMOS. It creates 32 interleaved clocks with 1.1-ps rms accuracy to drive 32 current-mode pipeline sub-ADCs. The ADC runs at up to 5.9 GSample\\/s. With calibration at 4 GSam- ple\\/s, it achieves an accuracy of 7.0 effective bits at DC and 6.1 effective bits on a 1-GHz input.

Ken Poulton; Robert Neff

96

The U. S. Geological Survey, Digital Spectral Library: Version 1 (0.2 to 3.0um)  

USGS Publications Warehouse

We have developed a digital reflectance spectral library, with management and spectral analysis software. The library includes 498 spectra of 444 samples (some samples include a series of grain sizes) measured from approximately 0.2 to 3.0 um . The spectral resolution (Full Width Half Maximum) of the reflectance data is <= 4 nm in the visible (0.2-0.8 um) and <= 10 nm in the NIR (0.8-2.35 um). All spectra were corrected to absolute reflectance using an NIST Halon standard. Library management software lets users search on parameters (e.g. chemical formulae, chemical analyses, purity of samples, mineral groups, etc.) as well as spectral features. Minerals from borate, carbonate, chloride, element, halide, hydroxide, nitrate, oxide, phosphate, sulfate, sulfide, sulfosalt, and the silicate (cyclosilicate, inosilicate, nesosilicate, phyllosilicate, sorosilicate, and tectosilicate) classes are represented. X-Ray and chemical analyses are tabulated for many of the entries, and all samples have been evaluated for spectral purity. The library also contains end and intermediate members for the olivine, garnet, scapolite, montmorillonite, muscovite, jarosite, and alunite solid-solution series. We have included representative spectra of H2O ice, kerogen, ammonium-bearing minerals, rare-earth oxides, desert varnish coatings, kaolinite crystallinity series, kaolinite-smectite series, zeolite series, and an extensive evaporite series. Because of the importance of vegetation to climate-change studies we have include 17 spectra of tree leaves, bushes, and grasses. The library and software are available as a series of U.S.G.S. Open File reports. PC user software is available to convert the binary data to ascii files (a separate U.S.G.S. open file report). Additionally, a binary data files are on line at the U.S.G.S. in Denver for anonymous ftp to users on the Internet. The library search software enables a user to search on documentation parameters as well as spectral features. The analysis system includes general spectral analysis routines, plotting packages, radiative transfer software for computing intimate mixtures, routines to derive optical constants from reflectance spectra, tools to analyze spectral features, and the capability to access imaging spectrometer data cubes for spectral analysis. Users may build customized libraries (at specific wavelengths and spectral resolution) for their own instruments using the library software. We are currently extending spectral coverage to 150 um. The libraries (original and convolved) will be made available in the future on a CD-ROM.

Clark, Roger N.; Swayze, Gregg A.; Gallagher, Andrea J.; King, Trude V. V.; Calvin, Wendy M.

1993-01-01

97

Geochemistry of the Neoproterozoic metasediments of Malhaq and Um Zariq formations, Kid metamorphic complex, Sinai, Egypt: Implications for source-area weathering, provenance, recycling, and depositional tectonic setting  

NASA Astrophysics Data System (ADS)

The Um Zariq and Malhaq formations occupy roughly the northern half of the Kid metamorphic complex of SE Sinai, in the NE part of the Arabian-Nubian Shield. The Um Zariq Formation metasediments are relicts of an old sedimentary sequence (Cryogenian; 813 ± 6 Ma), whereas the Malhaq Formation records several phases of Ediacaran sedimentation and volcanic activity (615-607 Ma). The Um Zariq Formation is mainly represented by well-bedded metapelitic schists, while the Malhaq Formation comprises a series of structureless to schistose felsic to intermediate metavolcanics interbedded with mica-rich phyllites and schists. The Um Zariq metasediments are depleted in SiO2, CaO and K2O and enriched in TiO2, Al2O3 and K2O relative to those of the Malhaq Formation. Aside from the relatively low Ni and Cr concentrations, compatible transition elements of these metasediments are comparable to average crustal contents. Except for marked Sr depletion, LILEs are around average continental crust values. Pronounced negative Nb-Ta anomalies and enrichment of Um Zariq samples in Th, U, Zr, Ti and Y relative to Malhaq ones are the main features of HFSEs. The REE patterns of all samples are parallel to sub-parallel LREE-enriched, with distinct negative Eu anomalies and weakly fractionated HREE segments. The source rocks of the Malhaq Formation metasediments underwent mild to moderate chemical weathering, whereas those of the Um Zariq Formation have suffered severe chemical weathering. These metasediments are predominately derived from felsic to intermediate igneous sources, with a particular slight addition from recycled sedimentary source to the Malhaq Formation metasediments. They are collectively geochemically immature and have suffered minor sedimentary recycling, with the experience of the Malhaq Formation metasediments from higher degree of sorting and reworking. The Malhaq and Um Zariq metasediments were originally deposited in a continental arc setting, most probably back-arc basin, despite the wide time span between their individual depositions.

El-Bialy, Mohammed Zaky

2013-08-01

98

A Visão do Universo Segundo a Concepção de um Grupo de Alunos do Ensino Médio de São Paulo  

NASA Astrophysics Data System (ADS)

Nesse trabalho foi identificada por meio de um questionário a visão de mundo sobre o Universo espaço e tempo entre 270 estudantes de Ensino Médio de três escolas de São Paulo. Constatou-se pouco conhecimento dos temas investigados sendo que apenas 20% dos alunos relacionaram as semanas com as fases da lua enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% reconheciam o Sol como uma estrela. Apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de astronomia seus conceitos ainda são inadequados havendo necessidade de aprimoramento da abordagem desses conteúdos pois apesar de popular a astronomia é veiculada de maneira pouco esclarecedora e com imprecissões.

Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

2005-12-01

99

Near Infrared (1.54 um) Luminescent Device and Optical Properties of Er-doped Gallium Nitride  

NASA Astrophysics Data System (ADS)

Erbium deoped semiconductors are of significant current interest for the development of comapct, efficient, and temperature-insensitive electro-luminescence devices operating at the optical communication wavelength of 1.54 um. Recently, we have developed a hybrid device InGaN/GaN:Er LED operating 1.54 um. In these experiment a Nichia InGaN LED with peak emission bands at 450 nm and 520 nm was employed to excited the Er3+ oinos in the GaN layer grown on a sapphire substrate, because the photoluminescence (PLE) excitation spectrum of the film indicated a strong absorption in this region. The epoxy bubble of the InGaN LED was removed and polished. The GaN:Er film was placed directly on the top of the LED. The DC forward voltage and current of the InGaN LED was 2.98 V and 20 mA, respectively. The PLE spectra of Er:GaN was sensitive to the back ground concentrations of oxygen and carbon. For samples with the high back ground concentrations of carbon (C, 10^21 cm-3) and oxygen (O, 10^20 cm-3) a broadband PLE spectrum 400-800 nm was observed. The Er:GaN sample with the low concentrations of C and O ( 10^19 cm-3) did not show the broad PLE band, but revealed direct intra-4f transitions of 450 nm, 490 nm, and 520 nm. Details of PLE and near-infrared luminescence properties of Er:GaN will be discussed.

Seo, J. T.; Hommerich, U. H.; MacKenzie, J. D.; Abernathy, C. R.; Pearton, S. J.; Zavada, J. M.

1999-11-01

100

The yfhQ gene of Escherichia coli encodes a tRNA:Cm32/Um32 methyltransferase  

PubMed Central

Background Naturally occurring tRNAs contain numerous modified nucleosides. They are formed by enzymatic modification of the primary transcripts during the complex RNA maturation process. In model organisms Escherichia coli and Saccharomyces cerevisiae most enzymes involved in this process have been identified. Interestingly, it was found that tRNA methylation, one of the most common modifications, can be introduced by S-adenosyl-L-methionine (AdoMet)-dependent methyltransferases (MTases) that belong to two structurally and phylogenetically unrelated protein superfamilies: RFM and SPOUT. Results As a part of a large-scale project aiming at characterization of a complete set of RNA modification enzymes of model organisms, we have studied the Escherichia coli proteins YibK, LasT, YfhQ, and YbeA for their ability to introduce the last unassigned methylations of ribose at positions 32 and 34 of the tRNA anticodon loop. We found that YfhQ catalyzes the AdoMet-dependent formation of Cm32 or Um32 in tRNASer1 and tRNAGln2 and that an E. coli strain with a disrupted yfhQ gene lacks the tRNA:Cm32/Um32 methyltransferase activity. Thus, we propose to rename YfhQ as TrMet(Xm32) according to the recently proposed, uniform nomenclature for all RNA modification enzymes, or TrmJ, according to the traditional nomenclature for bacterial tRNA MTases. Conclusion Our results reveal that methylation at position 32 is carried out by completely unrelated TrMet(Xm32) enzymes in eukaryota and prokaryota (RFM superfamily member Trm7 and SPOUT superfamily member TrmJ, respectively), mirroring the scenario observed in the case of the m1G37 modification (introduced by the RFM member Trm5 in eukaryota and archaea, and by the SPOUT member TrmD in bacteria).

Purta, Elzbieta; van Vliet, Francoise; Tkaczuk, Karolina L; Dunin-Horkawicz, Stanislaw; Mori, Hirotada; Droogmans, Louis; Bujnicki, Janusz M

2006-01-01

101

EFEITO DA POSIÇÃO RELATIVA DA LINHA LATERAL DE UM EQUIPAMENTO DE IRRIGAÇÃO DO TIPO PIVÔ CENTRAL NA UNIFORMIDADE DE DISTRIBUIÇÃO DE ÁGUA E EFICIÊNCIA DA IRRIGAÇÃO  

Microsoft Academic Search

RESUMO Neste trabalho, avaliou-se o efeito da posição da linha lateral de um equipamento de irrigação do tipo pivô central na uniformidade de distribuição de água, lâmina de irrigação aplicada, eficiência de aplicação, eficiência de armazenamento, adequabilidade da irrigação e velocidade de deslocamento da torre final. Foram avaliadas três posições: aclive d e 3 ,87%, nível e d eclive de

João Luis Zocoler; Luis Eduardo; Vilar Cesar; Luiz Sérgio Vanzela

102

Composição florística da vegetação arbórea de um trecho de floresta estacional semidecídua em Viçosa, Minas Gerais, e espécies de maior ocorrência na região  

Microsoft Academic Search

RESUMO - É grande a demanda por estudos ecológicos em florestas que possam embasar trabalhos de recuperação, conservação da biodiversidade e apoio à legislação ambiental. Entre esses estudos, primordialmente está o levantamento da flora. Nesse sentido, este trabalho teve como objetivo determinar a composição florística de um trecho da Reserva da Biologia, em Viçosa, MG, em regeneração natural há 80

Walnir Gomes Ferreira Júnior; Alexandre Francisco da Silva; João Augusto Alves Meira Neto; Carlos Ernesto Gonçalves Reynaud Schaefer; Arildo de Souza Dias; Maíra Ignácio; Maria Cláudia Melo Pacheco de Medeiros

2007-01-01

103

Technology Development for High-Efficiency Solar Cells and Modules Using Thin (<80 um) Single-Crystal Silicon Wafers Produced by Epitaxy: June 11, 2011 - April 30, 2013  

SciTech Connect

Final technical progress report of Crystal Solar subcontract NEU-31-40054-01. The objective of this 18-month program was to demonstrate the viability of high-efficiency thin (less than 80 um) monocrystalline silicon (Si) solar cells and modules with a low-cost epitaxial growth process.

Ravi, T. S.

2013-05-01

104

Geochemistry of the Neoproterozoic metasediments of Malhaq and Um Zariq formations, Kid Metamorphic Complex, Sinai, Egypt: implications for source-area weathering, provenance, recycling, and depositional tectonic setting  

NASA Astrophysics Data System (ADS)

The Kid Metamorphic Complex of SE Sinai represents a thick volcano-sedimentary succession that underwent polyphase deformation and greenschist to upper amphibolite facies metamorphism in the NE part of the Arabian-Nubian Shield (ANS). The Malhaq and Um Zariq Formations, the target of this study, occupy roughly the northern half of this complex. The Malhaq Formation records several phases of Ediacaran sedimentation and volcanic activity (615-607 Ma), whereas Um Zariq Formation metasediments are relicts of an older sedimentary sequence (Cryogenian; 813±6 Ma). The Malhaq Formation comprises a series of dark gray structureless to schistose felsic to intermediate metavolcanics interbedded and intercalated with fine- to medium-grained foliated mica-rich phyllites and schists, while the Um Zariq Formation is a dominantly metasedimentary sequence, mainly represented by well-bedded metapelitic schists. Malhaq metasediments are enriched in SiO2, CaO and K2O and depleted in TiO2, Al2O3 and K2O relative to those of Um Zariq Formation. Aside from the relatively low Ni and Cr concentrations, compatible transition elements of these metasediments are comparable to average crustal contents. Except for marked Sr depletion, LILEs are around average continental crust values. Pronounced negative Nb-Ta anomalies in all samples, and general enrichment of Um Zariq samples in Th, U, Zr, Ti and Y relative to Malhaq ones are the main features of HFSEs. The REE patterns of all samples are parallel to sub-parallel LREE-enriched, with distinct negative Eu anomalies and weakly fractionated HREE segments. Geochemical investigations have revealed that the source rocks of Malhaq Formation metasediments underwent mild to moderate chemical weathering, whereas those of Um Zariq Formation have suffered severe chemical weathering. These metasediments are predominately derived from felsic to intermediate igneous sources, with a particular slight addition from recycled sedimentary source to the Malhaq Formation metasediments. They are collectively geochemically immature and have suffered minor sedimentary recycling, with the bearing of Malhaq Formation metasediments from advanced degree of sorting and reworking. The Malhaq and Um Zariq metasediments had been originally deposited in a continental arc setting, most probably back-arc basin, despite the wide time span between their individual depositions. Various geochemical evidences imply that the main source from which these two chronologically distinct metasediments (Ediacaran vs. Cryogenian) have been derived from the juvenile (arc-type) Arabian-Nubian Shield crust.

El-Bialy, Mohammed Z.

2013-04-01

105

Establishment and characterization of UM-EC-2, a tamoxifen-sensitive, estrogen receptor-negative human endometrial carcinoma cell line.  

PubMed

UM-EC-2 was established from a patient with poorly differentiated stage IB endometrial carcinoma. This cell line produces tumors in nude mice that have the same histological features as the patient's tumor. UM-EC-2 cells express b2-microglobulin, the epidermal growth factor receptor (EGF), and the H blood group antigen. This membrane antigen phenotype is consistent with cells of human endometrial origin. The karyotype of UM-EC-2 is fairly complex, with rearrangements affecting all chromosomes except 3, 10, 14, 19, and 20. There were two populations of cells, a hyperdiploid population with a modal number of 53-55 and a hypertetraploid population with a modal number of 109. A postulated sequence of events before and after tetraploidization is suggested based on the number of copies of individual chromosomes and rearrangements. Comparison of the UM-EC-2 karyotype to that of UM-EC-1 (a previously described line from a different patient with endometrial carcinoma) revealed that the two lines share eight very similar chromosome changes, which include loss of most of chromosome 4, breakpoints affecting proximal bands on 8p, loss of most of 9q, a breakpoint at 12q22, loss of 13q, breakpoints in proximal bands on 18q, and a breakpoint at 22p11. These changes may represent nonrandom chromosome abnormalities in poorly differentiated endometrial cancer. Estrogen (ER) and progesterone (PgR) receptors were not detected in either the primary tumor or the cell line. Nevertheless, UM-EC-2 cells were very sensitive to growth inhibition by tamoxifen (TAM) in vitro. One micromolar TAM caused 50% inhibition of cell growth, 2.5 microM caused cytostasis, and 5 microM TAM was cytotoxic, killing all cells after 5-7 days of exposure to the drug. Paradoxically, 100 nM estradiol (E2) caused a moderate increase in the growth of the cells but it did not prevent or reverse growth inhibitory effects of TAM. These findings support the concept that in some tumors TAM causes growth inhibition by an ER-independent mechanism. UM-EC-2 cells were also sensitive to growth regulation by EGF. Thus, these cells provide a new in vitro model of human endometrial cancer in which the roles of both TAM and EGF as growth regulatory substances can be investigated. PMID:2344964

Grenman, S E; Worsham, M J; Van Dyke, D L; England, B; McClatchey, K D; Babu, V R; Roberts, J A; Mäenpää, J; Carey, T E

1990-05-01

106

Percepção astronómica de um grupo de alunos do ensino médio de uma escola da rede estadual de São Paulo  

NASA Astrophysics Data System (ADS)

Sendo a Astronomia uma das cièncias mais antigas da humanidade, e considerando sua importáncia histórica e cultural, é de extrema releváncia que tópicos relacionados a ela sejam tratados nas escolas. Embora os Parámetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as Orientaçiacute;es Complementares aos Parámetros (PCN+) apontem a importáncia de uma abordagem significativa de conceitos relacionados à Astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano e sejam alvos da curiosidade natural dos jovens. Da observação dessa curiosidade em alunos de uma escola pública paulista, na cidade de Suzano, surgiu o interesse em investigar os conhecimentos básicos em Astronomia dos alunos do Ensino Médio desta escola, constituindo-se este como principal objetivo desta pesquisa. Para tanto foi elaborado um questionário de múltipla escolha aplicado inicialmente a 34 alunos do primeiro ano e, posteriormente, a mais 310, distribuídos entre as très séries do Ensino Médio dos períodos matutino e noturno. Dessa forma, observou-se que 73,9% dos estudantes identificaram o Sol como sendo uma estrela, 67,1% mostraram compreender a sucessão entre dia e noite e 52,3% relacionaram o Big Bang à origem do Universo. Em contrapartida, apenas 34,5% relacionaram as estaçíes do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influència gravitacional simultánea da Lua e do Sol como responsável pelo fenòmeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distáncia e 34,2% reconheceram as estrelas cadentes como meteoros, evidenciando-se assim o pequeno discernimento dos estudantes quanto aos fenòmenos e termos astronòmicos do cotidiano. Além disso, foram comparadas as respostas de alun! os de diferentes séries e períodos, observando-se, dentre ou tras coi sas, que os estudantes do terceiro ano apresentam um percentual de acertos semelhante ao dos alunos do primeiro, caracterizando que a abordagem de tópicos relacionados à astronomia no Ensino Médio não tem contribuído de forma significativa para uma maior compreensão dos fenòmenos e conceitos.

de Oliveria, E. F.; Voelzke, M. R.

2009-03-01

107

Banded iron formations of Um Nar, Eastern Desert of Egypt: P–T–X conditions of metamorphism and tectonic implications  

NASA Astrophysics Data System (ADS)

Banded iron formations (BIF) in Um Nar, central eastern desert of Egypt, occur intercalated with schists of volcaniclastic and epiclastic origins within "ophiolitic–island arc rocks" of the Arabo–Nubian Shield. The BIF and its host rocks were affected by folding, thrusting, and regional metamorphism during the Pan-African Orogeny resulting in the development of north-verging overturned folds and E–W striking, S-dipping thrusts. Following the intrusion of granitoids, the entire sequence was refolded into south-plunging folds with NW–SE trending fold axes. Peak mineral assemblages of hornblende + plagioclase, and garnet + biotite + plagioclase + quartz in the host rocks, and andradite-rich garnet + epidote + hematite + magnetite + quartz in the BIF indicate metamorphism under epidote amphibolite facies conditions. Using the multiequilibrium approach of Thermocalc, and conventional thermobarometry, peak P–T conditions of metamorphism are estimated at 520 ± 30 °C, 5 ± 2 kbar. Fluids attending peak conditions in the oxide facies layers of the BIF were characterized by XCO2 ~ 0.03 and log fO2 ~ ? 40. Textural and mineral chemical criteria suggest that, following peak conditions, the rocks underwent a stage of near-isobaric cooling or cooling and compression characteristic of a counter-clockwise P–T path.

El-Shazly, A. K.; Khalil, K. I.

2014-05-01

108

Calcareous benthonic foraminifera across the Cretaceous/Paleocene transition of Gebel Um El-Ghanayem, Kharga Oasis, Egypt  

NASA Astrophysics Data System (ADS)

The studies of benthic calcareous foraminifera of the Maastrichtian-early Paleocene Dakhla Formation in Gebel Um El-Ghanayem (Western Desert, Egypt), improve reconstruction of depositional environments of these successions. In total, 68 taxa of benthic foraminifera were identified in the studied succession. The late Maastrichtian assemblages (Zone CF3) are dominated by calcareous foraminifera with tapered tests, this tapered taxon Loxostomum applinae, Lox. tegulatum various dentalinid taxa, and Buliminella cushmani dominate in CF3 Biozone. We thus interpret these faunas as being dominated by infaunal morphogroups, suggesting a moderately eutrophic environment. Danian assemblages are characterized by abundant epifaunal trochospiral species, such as Cibicidoides abudurbensis, Cibicidoides farafraensis, and Gyroidinoides girardanus. The infaunal morphogroups make up 25-47% of fauna in the Danian, in contrast to 62-76% in the Upper Maastrichtian. This dominance of the Danian benthic foraminiferal assemblages by epifaunal or mixed epifaunal/infaunal morphogroups suggests that the food supply to the benthos was less abundant than in the latest Cretaceous. The Cretaceous/Paleocene boundary (K/Pg) is within the upper unit of the Lower Kharga Member and marked by a hiatus in at least the top of CF3 Zone of the Upper Maastrichtian to the Lower Paleocene (base Plc Zone).

Orabi, Orabi H.; Khalil, Hamza M.

2014-08-01

109

PROBLEMAS ENTOMOLÓGICOS NA VITICULTURA DO VALE DO SÃO FRANCISCO  

Microsoft Academic Search

In the agricultural region of Petrolina- PE\\/Juazeiro-BA, located in the São Francisco River VaIIey, in the Brazilian Semi-Arid region, grape is one of the most technified and important crops. Social demands for better living quality have favored the use of new technologies, like Fruit lntegrated Production System (FIP), which assures a rational production, a great economy and environmental preservation. With

Francisca Nemaura; Pedrosa Haji

110

ALIMENTOS LIBRES DE GLUTEN: UN PROBLEMA AÚN SIN RESOLVER  

Microsoft Academic Search

RESUMEN: La celiaquía es una patología gastrointestinal causada por una intolerancia total y permanente a las proteínas del gluten. En medicina se están registrando importantes avances para anticipar el diagnóstico de nuevas formas de manifestación de esta patología engañosa y multifacé- tica. En varios países se desarrollan trabajos tendientes a lograr técnicas analíticas más eficientes para cuantificar gluten en alimentos

María Elisa García

2006-01-01

111

A Neutron Transport Problem UN Problema di Trasporto di Neutroni.  

National Technical Information Service (NTIS)

A method is given to determine the critical states of a nuclear reactor. Considering the Boltzman equation in integral form, it is shown that the eigenvalues of a special form of this equation provide the answer. The Ritz method is used to find an approxi...

G. Busoni G. Frosali L. Mangiarotti

1975-01-01

112

Colombia: Los problemas de competitividad de un país en conflicto  

Microsoft Academic Search

La persistencia del conflicto interno en Colombia inhibe todos los elementos principales que contribuyen a la determinación de la competitividad de la economía nacional, que son los siguientes: (i) el monto de sus recursos productivos; (ii) la calidad y productividad de los mismos; (iii) la eficiencia con que operan sus mercados; (iv) el estado de su infraestructura; (v) la capacidad

Alberto Melo

2003-01-01

113

Aedes albopictus in Italia: un problema sanitario sottovalutato  

Microsoft Academic Search

Summary (Aedes albopictus in Italy: an underestimated health problem). - Since 1990, Ae. albopictus has spread in 9 regions and 30 provinces of the country. This species was introduced in Italy in shipments of scrap tires form the USA. In Italy, Ae. albopictus is the major biting pest throughout much of its range and, although there is no evidence that

Roberto ROMI

114

Decor(um)  

Microsoft Academic Search

Over the years the profession of interior design has struggled with its identity and place in the professional world of design. Practitioners and educators have conscientiously worked to distance themselves from the seemingly unattractive and `unprofessional' parts of the field, namely decoration and ornamentation. It seems, however, that no matter what steps are taken to redefine the profession and separate

Sarah Elizabeth Zenti

2011-01-01

115

Remote sensing detection of gold related alteration zones in Um Rus area, Central Eastern Desert of Egypt  

NASA Astrophysics Data System (ADS)

Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Phased Array L-band Synthetic Aperture Radar (PALSAR) images covering the Um Rus area in the Central Eastern Desert of Egypt were evaluated for mapping geologic structure, lithology, and gold-related alteration zones. The study area is covered by Pan-African basement rocks including gabbro and granodiorite intruded into a variable mixture of metavolcanics and metasediments. The first three principal component analyses (PCA1, PCA2, PCA3) in a Red-Green-Blue (RGB) of the visible through shortwave-infrared (VNIR + SWIR) ASTER bands enabled the discrimination between lithological units. The results show that ASTER band ratios ((2 + 4)/3, (5 + 7)/6, (7 + 9)/8) in RGB identifies the lithological units and discriminates the granodiorite very well from the adjacent rock units.The granodiorites are dissected by gold-bearing quartz veins surrounded by alteration zones. The microscopic examination of samples collected from the alteration zones shows sericitic and argillic alteration zones. The Spectral Angle Mapper (SAM) and Spectral Information Divergence (SID) supervised classification methods were applied using the reference spectra of the USGS spectral library. The results show that these classification methods are capable of mapping the alteration zones as indicated by field verification work. The PALSAR image was enhanced for fracture mapping using the second moment co-occurrence filter. Overlying extracted faults and alteration zone classification images show that the N30E and N-S fractures represent potential zones for gold exploration. It is concluded that the proposed methods can be used as a powerful tool for ore deposit exploration.

Amer, Reda; Kusky, Timothy; El Mezayen, Ahmed

2012-01-01

116

The Dynamics of Transmission and Spatial Distribution of Malaria in Riverside Areas of Porto Velho, Rondônia, in the Amazon Region of Brazil  

Microsoft Academic Search

The study area in Rondônia was the site of extensive malaria epidemic outbreaks in the 19th and 20th centuries related to environmental impacts, with large immigration flows. The present work analyzes the transmission dynamics of malaria in these areas to propose measures for avoiding epidemic outbreaks due to the construction of two Hydroelectric Power Plants. A population based baseline demographic

Tony Hiroshi Katsuragawa; Luiz Herman Soares Gil; Mauro Shugiro Tada; Alexandre De Almeida E. Silva; Joana D'arc Neves Costa; Maisa da Silva Araújo; Ana Lúcia Escobar; Luiz Hildebrando Pereira da Silva; Matthew Baylis

2010-01-01

117

Vínculos sobre um modelo de quartessência de Chaplygin usando observações do satélite chandra da fração de massa de gás em aglomerados de galáxias  

NASA Astrophysics Data System (ADS)

Observações de Supernovas do tipo Ia mostram que a expansão do Universo está acelerando. Segundo as equações de Einstein uma componente com pressão negativa (energia escura) é necessária para explicar a aceleração cósmica. Além da energia escura é usualmente admitido que no Universo há também uma matéria exótica com pressão zero, que é chamada de matéria escura. Essa componente possui um papel fundamental na formação de estruturas no Universo. Recentemente tem se explorado a possibilidade de que matéria e energia escura poderiam ser unificadas através de uma única componente, que tem sido denominada de quartessência. Um exemplo de fluido com essas características é o Gás de Chaplygin Generalizado, que possui uma equação de estado da forma p = -A/ra. Inicialmente consideramos o caso especial a = 1 (gás de Chaplygin) e vinculamos parâmetros do modelo utilizando observações em raios-X do satélite Chandra da fração de massa de gás em aglomerados de galáxias. Uma comparação dos vínculos obtidos com esse teste com outros testes, tais como supernovas e idade do Universo, mostra que esse teste é bastante restritivo. Exibiremos ainda resultados para o caso em que a curvatura é nula e o parâmetro a está compreendido no intervalo -1 < a 1.

de Souza, R. S.

2003-08-01

118

User's manual (UM) for the enhanced logistics intratheater support tool (ELIST) software segment version 8.1.0.0 for solaris 7.  

SciTech Connect

This document is the User's Manual (UM) for the Enhanced Logistics Intratheater Support Tool (ELIST) Software Segment. It tells how to use the end-user and administrative features of the segment. The instructions in Sections 4.2.1, 5.3.1, and 5.3.2 for the end-user features (Run ELIST and Run ETEdit) only cover the launching of those features in the DII COE environment; full details on the operation of ELIST and ETEdit in any environment can be found in the documents listed in Section 2.1.3 and referenced elsewhere in this document. On the other hand, complete instructions for the administrative features (Add Map Data and Delete Map Data) are presented in Sections 4.2.2, 5.3.3, and 5.3.4 of this document.

Dritz, K.

2002-03-06

119

Computacao Algebrica no Calculo das Variacoes: Determinacao de Simetrias e Leis de Conservacao  

Microsoft Academic Search

Resumo. Os problemas de optimizacao dinamica (em espacos de funcoes) trata- dos pelo calculo das variacoes, sao normalmente resolvidos por recursoas condicoes necessarias de Euler-Lagrange, que sao equacoes diferenciais de segunda ordem (ou de ordem superior, quando os problemas variacionais envolvem derivadas de ordem superior a um). Estas equacoes sao, em geral, nao lineares e de dif´õcil resolucao. Uma forma

Paulo D. F. Gouveia; Delfim F. M. Torres

2004-01-01

120

Utilização de hardware reconfigurável para acelerar a satisfação booleana  

Microsoft Academic Search

* Trabalho financiado com a bolsa da FCT-PRAXIS XXI\\/BD\\/21353\\/99 Resumo - Este artigo apresenta um estudo de possibilidade de aceleração da satisfação booleana com a ajuda do hardware reconfigurável. A satisfação booleana (SAT) é um problema importante que tem muitas aplicações em CAD e outras áreas. Neste artigo propomos uma técnica de desenvolvimento orientada a problema em geral para acelerar

Iouliia Skliarova; António B. Ferrari

2001-01-01

121

Educação continuada: um levantamento de necessidades da equipe de enfermagem 1 Lifelong learning: a survey on the nursing team necessities Educación continuada: un diagnóstico de necesidades del equipo de enfermería  

Microsoft Academic Search

RESUMO: A Educação Continuada é o componente essencial dos programas de formação e desenvolvimento de recursos humanos das instituições. O desenvolvimento da equipe de enfermagem é um dos fatores que pode assegurar a qualidade do atendimento ao cliente e a sobrevivência da instituição neste cenário de mudanças e competitividade. Assim, neste estudo fizemos alguns diagnósticos através do levantamento de necessidades

Milena Froes da Silva; Fabiana Alves da Conceição; Maria Madalena Januário Leite

122

A linear 0.18 um CMOS Distributed Low Noise Amplifier from 3.1 to 10.6 GHz with Cascode Cells  

NASA Astrophysics Data System (ADS)

In this paper, we propose a design methodology of 3.1-10.6GHz Ultra-wideband (UWB) Distributed Low Noise Amplifier using standard 0.18 um CMOS technology which is applicable in telecommunication. The four cells DLNA, each cell contains cascode architecture, can be use in broadband applications. The proposed distributed low noise amplifier has a good input and output matching over the full band of 3.1-10.6 GHz. We achieve acceptable results for low noise amplifier as a flat power gain of 12.5 dB (S21) from 3.1 to 10.6 GHz, which is ripple 0.3 dB over the full UWB band. An input impedance matching is <-15 dB (S11) and an output impedance matching of <-15 dB (S22) over the entire band. Our measurements show this LNA achieves the minimum noise figure of 2.8 dB.

Shamsadini, Shila; Kashani, Farokh Hojat; Bathaei, Neda

2011-05-01

123

Laser sources at 2 um and 3 um  

NASA Astrophysics Data System (ADS)

Two laser systems emitting at 2 and 3 micrometers have been developed for application in the biomedical field, such as photoablation and microsurgery. The design involved the evaluation of active materials, the optimization of pumping chamber and the analysis of different configurations of the resonant cavity. Holmium, Thulium and Erbium active ions in the YAG host have been considered. A complete characterization of the laser behavior has been carried out for the most interesting combinations of components. The Erbium laser has been also operated in Q-switch regime. The achieved results are comparable with the state of the art performances on the international market.

Nava, Enzo; Garifo, Luciano; Cubeddu, Rinaldo; Valentini, Gianluca; Ferrario, Angelo

1996-01-01

124

Modelling future changes in climate, ozone-depleting substances and ozone precursor emissions using the whole-atmosphere UM-UKCA model  

NASA Astrophysics Data System (ADS)

Using the recently upgraded whole-atmosphere UM-UKCA chemistry-climate model, we investigate the atmospheric response to future changes in a) greenhouse gases under the RCP4.5 and 8.5 scenarios for climate change, b) ozone-depleting substances (ODS) and a recovery of the ozone layer and c) ozone precursor emissions and tropospheric oxidising capacity. In addition, we combine these scenarios in order to explore the interactions between individual perturbations. Within this framework, the coupled stratosphere-troposphere system and whole-atmosphere chemistry allows us to study the impact of changes in composition of the stratosphere on the troposphere and vice versa. We find that by the year 2100: 1) the stratosphere significantly impacts the troposphere via changes in stratosphere-troposphere exchange (STE) but the chemical changes induced in the troposphere do not impact the stratosphere, 2) perturbations are linearly additive with regard to the total ozone column and tropospheric odd oxygen budget, 3) while the Brewer-Dobson Circulation strengthens under climate change (with an increase in the DJF 70hPa tropical upwards mass flux of ~20% at RCP4.5 and exceeding 30% at RCP8.5), this strengthening is offset by ozone recovery (which on its own leads to a decrease in the mass flux of ~10%) and 4) tropospheric ozone decreases given mitigation of its precursor emissions (with a 10% decrease in ozone burden) but this can be offset by climate change at both RCP4.5 and 8.5 and stratospheric ozone recovery (increasing the burden by 6-13%).

Banerjee, Antara; Maycock, Amanda; Archibald, Alexander; Telford, Paul; Abraham, Luke; Braesicke, Peter; Pyle, John

2014-05-01

125

Idosos atendidos em serviço de emergência de saúde mental: características demográficas e clínicas Elderly treated in mental health emergency rooms: demographic and clinic characteristics  

Microsoft Academic Search

O envelhecimento populacional vem provocando um aumento contínuo no número de idosos que buscam atendimento para problemas de saúde mental. Este trabalho teve como objetivo investigar os transtornos mentais que mais freqüentemente levam o idoso a um serviço de emergência psiquiátrica. Todos os idosos atendidos entre 1 o de janeiro e 31 de dezembro de 1997 no pronto-socorro de saúde

Osvaldo P. Almeida

126

PROGRAMAÇÃO DE TRANSFERÊNCIA DE DERIVADOS DE PETRÓLEO EM REDE DUTOVIÁRIA USANDO ALGORITMO GENÉTICO  

Microsoft Academic Search

O modal dutoviário é reconhecido como o meio mais eficaz de se transportar grandes volumes de petróleo e seus derivados por longas distâncias, mas que também exige um grande controle operacional. Isto torna a otimização do transporte de produtos neste sistema dutoviário, um problema de alta relevância do ponto de vista econômico, já que o preço final destes produtos depende

Rennó Frota; Moraes Alves

127

El Ruido: Un Problema para la Salud (Noise: A Health Problem).  

ERIC Educational Resources Information Center

This booklet contains nine sections describing ways in which noise may endanger health and well-being. Sections are included on: (1) hearing loss; (2) heart disease; (3) other reactions by the body; (4) effects on the unborn; (5) special effects on children; (6) intrusion at home and work; (7) mental and social well-being; and (8) danger to life…

Environmental Protection Agency, Washington, DC. Office of Noise Abatement and Control.

128

ANSIEDAD Y DEPRESIÓN: EL PROBLEMA DE LA DIFERENCIACIÓN A TRAVÉS DE LOS SÍNTOMAS  

Microsoft Academic Search

SUMMARY The differentiation between the symptoms of anxiety and depres- sion is one of the most important problems in psychology as the dilemma profoundly affects the diagnosis and clinical intervention. According to the epidemiological data there is a strong comorbility between the two types of disorder. Nevertheless, it is not known which one of them precedes or predisposes to the

Diana Agudelo; Gualberto Buela-Casal; Charles Donald Spielberger

129

LAS CIUDADES ESPAÑOLAS Y EL RIESGO DE INUNDACIÓN: PERMANENCIA Y CAMBIO DE UN PROBLEMA CRÓNICO  

Microsoft Academic Search

Spanish cities and flood risk: permanency and change of a chronic problem. We study the incidence of flood risk in Spanish cities throughout the history. Through this analysis we can prove the role performed by physical and human factors in the spatial distribution and chronological evolution of this risk. Furthermore, its recent trends are explained in relation- ship to the

Juan Carlos; García Codron

130

Colonias: Problems and Promise. Desperate Situations, Local Innovations = Colonias: Problemas y Promesa. Situaciones Dificiles, Innovaciones Locales.  

ERIC Educational Resources Information Center

Colonias--unincorporated, low-income settlements endemic to the U.S. borderlands--have inadequate infrastructure and dismal living conditions, but also provide a creative solution to the housing dilemma faced by many border families. Colonias are most common in Texas and New Mexico, primarily as a result of weak rural planning laws, and are…

Borderlines, 1998

1998-01-01

131

MODELOS DE DURACIÓN Y GESTIÓN DEL RIESGO DE INTERÉS: ¿UN PROBLEMA DE DIMENSIÓN?  

Microsoft Academic Search

The group of duration models has grown rapidly during last years, offering manynew approaches for interest rate risk management in delta or delta-gamma frameworks.This paper attempts to make up for the lack of empirical evidence concerning theperformance of some of the most realistic duration models in interest rate riskmanagement by analyzing their effectiveness to immunize fixed income portfolios. Tothis end,

Gloria M. Soto Pacheco

2002-01-01

132

GEOFÍSICA APLICADA AL PROBLEMA DE LA INTRUSIÓN SALINA EN LOS ACUÍFEROS COSTEROS DE COSTA RICA  

Microsoft Academic Search

Geophysical prospection is a complement of hydro- geochemical methods, that allows a good delimitation of the saline intrusion in three pacific coastal aquifers of Costa Rica. The methodology includes: well logging (electrical resistivity and temperature), electrical soun- dings and pseudosections, slingram and transitory elec- tromagnetic soundings, profiles and maps, to delimit the extension of the intrusion brine. An hidrogeologic study

Mario E. Arias Salguero; Asdruval Vargas; Roger Guérin

133

MÉTODO DE SOLUCIÓN DE PROBLEMAS Y CREATIVIDAD EN LA ENSEÑANZA DE INGENIERÍA  

Microsoft Academic Search

This paper provides young professors with tools to learn how to teach engineering helping them to develop effectively and efficiently their task and their academic development. Engineering education focuses heavily i problem solving, but many professors teach content only and expect students to solve problems automatically. Ma, engineering schools teach routines and diagnosis; students are not proficient at strategy, interpretation

Edilberto Guevara Pérez

134

A notação escrita na resolução de problemas por crianças pré-escolares  

Microsoft Academic Search

ABSTRACT - This study analyses how ,children from 4 to 6 years use written notation in subtraction ,problem ,solving. Thirty children from kindergarten to first levels were asked to solve ,four problems ,(two of the ,kind change ,and two of comparison), which involved numerical sets greater and smaller than 10. These problems were in a context which intented togive more

Ana Coêlho Vieira Selva; Ana Carolina Perrusi Brandão

2000-01-01

135

Autoconceito de crianças com dificuldades de aprendizagem e problemas de comportamento  

Microsoft Academic Search

The a im of this s tudy was to assess the self-concept of children with learning disability in comparison with children without learning disability. Fifty- eight school-age children were assessed, including: 32 Learning Disabled children, distinguished b y behavior problems, and 26 No Learning Disabled children. The c hild self-concept was assessed b y Piers Harris Self-Concept Scale and the

Indira Siqueira Stevanato; Sonia Regina Loureiro; Maria Beatriz Martins Linhares; Edna Maria Marturano

2003-01-01

136

Tod o conocimiento consiste en suscitar nuevos problemas a medida que resuelve los precedentes  

Microsoft Academic Search

In this paper I will present a revision of Piaget's equilibration theory in order to analyze its basic concepts through the epistemological framework depicted from non- monotonic logics. In particular I want to show that Piaget's equilibration model could be understood as a case of abductive reasoning. The paper's structure is in three main parts. The fi rst part presents

J. PIAGET

137

La incertidumbre estructural en el problema de la sostenibilidad. Una panorámica  

Microsoft Academic Search

Al incorporar el aspecto humano (junto con el económico y medio ambiental), a un sistema que pretende ser sostenible, éste se convierte en un sistema complejo, reflexivo y emergente. La propiedad de la reflexividad supone la existencia de una incertidumbre que no puede reducirse de ningún modo, pero que es necesario gestionar si se pretende la sostenibilidad del sistema. Este

Estrella Bernal Cuenca

2009-01-01

138

El embarazo en la adolescencia como problema público: una visión crítica  

Microsoft Academic Search

The present work is a review of the most commonly used arguments to define pregnancy during adolescence as a pub- lic problem: its supposed increase, contribution to acceler- ated population growth, adverse effects on maternal and child health and contribution to the persistence of poverty. Some elements are proposed for an alternative explanation with the intention of defining with more

CLAUDIO STERN

1997-01-01

139

Is overuse of sumatriptan a problem?A population-based study  

Microsoft Academic Search

Objective: Sumatriptan is highly efficacious in aborting acute attacks of migraine. Owing to recent reports of misuse of sumatriptan,\\u000a we performed a study of its use in a Danish population.\\u000a \\u000a Methods:\\u000a \\u000a \\u000a Data were retrieved from a prescription database covering a period of 27 months after release of the drug. Consumption was\\u000a described by the defined daily dose (DDD) unit and

D. Gaist; J. Hallas; S. H. Sindrup; L. F. Gram

1996-01-01

140

Expectativas, consumo de alcohol y problemas asociados en estudiantes universitarios de la ciudad de México  

Microsoft Academic Search

Objective. To assess the relationship between alcohol use expectancies, drinking patterns, and alcohol-related prob- lems, among college students in Mexico City. Material and methods. This cross-sectional study was conducted in October 1998. Study subjects were 678 male and female college students aged between 17 and 25 years, from pri- vate and public schools. Alcohol expectancies were meas- ured through the

Jazmín Mora-Ríos; Guillermina Natera

2001-01-01

141

Estado da Arte para Solução dos Problemas Vibroacústica por Métodos Numéricos  

Microsoft Academic Search

This paper presents the fundamentals of the numerical methods used in the acoustics and vibration fields as; Finite Elements Methods (FEM), Boundary Element Methods (BEM), Acoustic Rays, and Statistical Energy Analysis (SEA). State of arts and trend for future methods are presented. Some results are presented for practical study cases. RESUMO Neste trabalho serão apresentados os fundamentos dos métodos numéricos

Palestra Convidado; REFERÊNCIA PACS; Samir N. Y. Gerges

142

LCD with 7-um light management path  

NASA Astrophysics Data System (ADS)

New LCD cell structure includes plastic or glass substrates with ITO layers, Thin Crystal Film (TCF) polarizers coated on the ITO and a polyamide alignment layer on the top of the TCF. The TCF polarizer is molecularly oriented nano-film with the thickness in the range 60-600nm made by crystallization from lyotropic liquid crystals. First samples produced by Tecdis have demonstrated acceptable optical performance with superior viewing cone characteristics and thickness determined by the thickness of the plastic or glass walls plus 7 microns optical management path. Birefringence of the cell wall material is now not relevant to functionality of the display. It allows manufacturing plastic LCD's with robust environmental characteristics by using high temperature stable and birefringent inexpensive plastic.

Cobb, Carl C.; Gerbaz, Corrado; Lazarev, Pavel I.; Paukshto, Michael; Silverstein, L.

2002-05-01

143

ABBEY THEATRE: UM DRAMATURGO ENCONTRA SEU CAMINHO  

Microsoft Academic Search

John Millington Synge's presence was fundamental to the foundation and development of the Abbey Theatre, the main support to the Irish Dramatic Movement. Known as the most polemical playwright of this theatre in its early days, Synge was also one of its main directors. This approach tries to show the importance of the Abbey Theatre, which changed the Irish Drama

Geraldo Ferreira de Lima

144

350um polarimetry from CSO (Dotson+, 2010)  

NASA Astrophysics Data System (ADS)

The instrument, calibrations, and data analysis techniques have been described in detail by Schleuning et al. (1997PASP..109..307S), Dowell et al. (1998ApJ...504..588D), and Kirby et al. (2005PASP..117..991K). Table 1 lists the coordinates, observing dates, peak intensities and size and range of directions of the chop used for each object. (3 data files).

Dotson, J. L.; Vaillancourt, J. E.; Kirby, L.; Dowell, C. D.; Hildebrand, R. H.; Davidson, J. A.

2010-04-01

145

Sapphire fibers for 3-um delivery systems  

NASA Astrophysics Data System (ADS)

Er:YAG laser energy is highly absorbed by water, and therefore can provide excellent cutting precision with minimal thermal damage to surrounding tissue. Single crystal sapphire fibers are capable of transmitting Er:YAG laser energy with low loss and, additionally, they are chemically durable and bio-compatible. In this study, 300 micrometers diameter sapphire fibers were evaluated for use in surgical applications. Scattering and absorption losses, effective NA, and power handling capabilities were measured. The fibers had losses less than 1 dB/m, an effective NA of 0.2, and damage thresholds exceeding 1.2 kJ/cm2. The high damage thresholds were achieved only after a laser conditioning process at the proximal end of the fiber.

Plarke, Gwynneth M.; Chadwick, David; Nubling, Rick K.; Harrington, James A.

1995-05-01

146

Ulisses: Um Navegador Conceptual para Topic Maps  

Microsoft Academic Search

The ISO standard ISO-IEC 13250 - Topic Maps - provide a bridge between the domains of knowledge representation and information management. Topics and topic associations build a structured semantic link network above informa- tion resources. This research aims at visualizing this semantic layer efficiently, which is a critical issue as topic maps may contain millions of topics and associations. This

Giovani Rubert Librelotto; Jose Carlos Ramalho; Pedro Rangel Henriques

2005-01-01

147

ESTUDO GEOAMBIENTAL DO CURSO MÉDIO DA BACIA HIDROGRÁFICA DO RIO VERDE - CAMPO LARGO\\/PR  

Microsoft Academic Search

Resumo: A preocupação com questões ambientais tem crescido nos últimos anos motivada, principalmente, pela busca da sociedade por conhecimentos que apontem amenização e soluções de problemas tanto em áreas urbanas como rurais. Diante desta preocupação e utilizando como base teórico-metodológica a Geomorfologia Ambiental, este trabalho apresenta um estudo geoambiental do curso médio da bacia hidrográfica do rio Verde, localizado no

Maristela Moresco Mezzomo; Andreia Quintão Soares

148

Não ao sedentarismo, sim à saúde: contribuições da Educação Física escolar e dos esportes No to sedentarianism, yes to health: contributions of school physical education and sports No al sedentarismo, sí a la salud: contribuciones de la educación física en la escuela y de los deportes  

Microsoft Academic Search

RESUMO: Um dos grandes problemas enfrentados pelos povos no mundo se refere ao sedentarismo. Associado a ele, a obesidade, as cardiopatias, a diabetes e tantas outras doenças aparecem com índices muito preocupantes principalmente nas populações de jovens em idade escolar. A tecnologia parece agravar mais ainda este quadro. Entretanto, a prática da atividade física regular, com orientação, com vestimenta e

Ubiratan Silva Alves

149

DESENVOLVIMENTO DE INSTRUMENTO DE COLETA DE DADOS DE ENFERMAGEM PARA PACIENTES COM CÂNCER DE PULMÃO EM QUIMIOTERAPIA AMBULATORIAL Developing a Nursing Data Colleting Instrument to Patients with Lung Cancer Treated by Chemotherapy in Ambulatory Desarrollo de Instrumento de Recogida de Datos de Enfermería para Pacientes con Cáncer de Pulmón en Quimioterapia Ambulatoria  

Microsoft Academic Search

Resumen O câncer é um grave problema de saúde pública, e, dentre suas variedades, há o câncer de pulmão, que vem crescendo na população brasileira e mundial. A principal causa do câncer de pulmão é o tabagismo. Há três formas de tratamento: cirurgia, radioterapia e quimioterapia; para essa patologia a mais utilizada é a terceira. A enfermeira deve estar apta

Salvadori AM; Lamas JLT; Anita Moda Salvadori; José Luiz Tatagiba Lamas; Cláudia Zanon

150

Vinhoto e cama de frango como coadjuvantes na compostagem de bagaço de cana de açúcar  

Microsoft Academic Search

Resumo: Atualmente, a agricultura está passando por um proc esso de modernização, trazendo com isso inúmeros fatores negativos que influenciam na degradação do meio ambiente. Dejetos estão sendo jogados em lugares impróprios trazendo danos ao ar, solo e águas. Percebendo a gravidade deste problema, este trabalho foi realiza do visando contribuir para o melhoramento das condições ambientais e propor renda

Fernando Lira; Renato Cassol de Oliveira

2008-01-01

151

Isictometrics * : toward an alternative vision and process  

Microsoft Academic Search

Resumo A medição de bens e de fenômenos intangíveis traz dificuldades materiais e conceituais. Como a informação e as tecnologias da informação e da comunicação - TICS se estendem por grande parte da sociedade, a disponibilidade de indicadores válidos é um problema sério. As primeiras tentativas da escola de economia da informação trataram de adaptar as medidas socio-econômicas que existiam

Michel J. Menou

2001-01-01

152

Towards a Solution of the Problem of Cercospora Beticola on Sugar Beet (Prilog Resavanju Problema Cercospora Beticola NA Secernoj Repi).  

National Technical Information Service (NTIS)

Results are given of field investigations to establish the efficacy of some chemical preparations in the control of Cercospora beticola, the optimal date for application, and which of the two above mentioned principles of chemical control better suits Yug...

A. Maric

1970-01-01

153

Contaminación por nitrógeno inorgánico en los ecosistemas acuáticos: problemas medioambientales, criterios de calidad del agua, e implicaciones del cambio climático  

Microsoft Academic Search

climate change. The major environmental problems related to inorganic nitrogen pollution in aquatic ecosystems are: (1) acidification of lakes and rivers with low or reduced alkalinity; (2) eutrophication of fresh and marine waters (with the additional problem of toxic algae); and (3) direct toxicity of nitrogenous compounds to aquatic animals. Additionally, inorganic nitrogen pollution could induce adverse effects on human

J. A. Camargo; A. Alonso

154

Delimitacion de las Zonas Dialectales de Mexico: Objetivos y Problemas (Delimitation of Dialect Zones in Mexico: Objectives and Problems)  

ERIC Educational Resources Information Center

Before creating a linguistic map of Mexican dialects, it is necessary to determine the dialect regions of the country. An extensive questionnaire must be written and distributed to collect data from a representative sample of the population for an accurate picture of the language. (CK) (Text in Spanish.)

Blanch, Juan M. Lope

1975-01-01

155

Problemas de alimentação em crianças com doença do refluxo gastroesofágico*** Feeding disorders in children with gastro-esophageal reflux disease  

Microsoft Academic Search

Background: feeding\\/eating disorders are frequent in pediatric patients and, in some cases, can be associated to an upper digestive motility disorder. Gastro-esophageal reflux is, nowadays, considered a risk factor for the development of feeding\\/eating disorders. Aim: to verify the occurrence of feeding\\/eating disorders in patients with Gastro-Esophageal Reflux Disease (GERD) determined by the 24-H esophageal pH monitoring evaluation. Method: an

Larissa Vieira Drent; Elizete Aparecida; Lomazi da Costa Pinto

2007-01-01

156

Aportes del Aprendizaje Basado en Problemas (ABP) en la ensenanza de la Fisiologia Animal en un programa de Zootecnia  

NASA Astrophysics Data System (ADS)

Based on difficulties observed on the subject of technical-scientific conceptualization and the integration of theory and practice in learning animal physiology for students in the Animal Science program at the National University of Colombia in Medellin, this research paper proposes a problem-based learning strategy founded on the method of Problem Based Learning (PBL), applied specifically to the issues of thermoregulation and physiological stress in domestic animals. In this case study, a sample size of eight students was presented with a pedagogical problem during the first session that would then be solved during the course. In order to evaluate the process, three surveys were conducted called Level Test Formulations (NF) performed at different times of the trial: one before beginning the topic (NF 1), one after three theoretical classes had been given and before beginning the fieldwork (NF 2), and another one after the end of the process (NF 3). Finally, individual interviews were conducted with each student to know the students' perceptions regarding the method. The information obtained was subjected to a qualitative analysis and categorization, using the QDA Miner program which reviewed and coded texts from the surveys and individual interviews, supplemented in turn, by field observation, analyzing the conceptual change, the theory-practice relationship and the correlation between the variables and categories established. Among the main results obtained, it should be noted that following the implementation of PBL in this Animal Physiology course, support for conceptual change was demonstrated and the formulated problem served as a connector between theory and practice. Moreover, there was a fusion of prior knowledge with newly acquired knowledge, meaningful learning, improvement in the level of conceptualization and an increase in the scientificness of definitions; it also led to problem-solving and overcoming epistemological obstacles such as multidisciplinarity and nonlinearity. As a result of this research, it is recommended that this method be evaluated in other topics related to Animal Physiology, in other sciences, in larger sample sizes, as well as to address the issue of evaluation applied directly to this method. Key words: Problem Based Learning (PBL), conceptual change, integration of theory and practice, significatif learning, animal physiology, thermoregulation, physiological stress.

Reinartz-Estrada, Monica

157

Temas y problemas del idioma espanol en la prensa (Spanish Language Topics and Problems in the Press).  

ERIC Educational Resources Information Center

This section consists of reprints on the following topics: (1) the misuse of "en"; (2) anglicisms; (3) widespread use of vulgar language; (4) an interview with Emilio Criado on Spanish language variation; (5) use of the feminine in professional titles; and (6) Spanish, the national language of Latin American countries. (AMH)

El Brocense; And Others

1980-01-01

158

La Biotecnología en los Cultivos: Problemas Potenciales para los Países en Desarrollo  

NSDL National Science Digital Library

Excerpts from an Oxfam report examine GM crops are an answer to world hunger for some. To others, these crops are a health risk and an environmental threat because some GM crops: have proven to be genetically unstable, do not do what they were designed to do, are a risk to human health, particularly children, cause animals who eat them to become immune to antibiotics, and spread and destroy natural crops.

Laura Spinney (Oxfam GB;)

1998-05-01

159

Comparative research on medicine application with 0.53-um, 1.06-um, and 1.32-um Nd:YAG lasers  

NASA Astrophysics Data System (ADS)

Because of its high power and excellent optical features, laser has almost been applied to everywhere of medical research and clinic. Over the past several years, laser medical has achieved a rapid progress, and laser medical instruments has developed promptly, each new wavelength can be successfully applied in diagnostic and treatment of diseases. Among the medical lasers, Nd:YAG solid-state laser systems have proven useful in surgical use operate, such as neurosurgery, gastroenterology, cardioangiology, urology, gynecology, dermatology and ENT. As with other solid-state lasers, the Nd:YAG laser can be made to emit various wavelengths by means of suitable resonator configurations and some newest solid-state laser technology, pumped by the Krypton lamp, the Nd:YAG laser at room temperature exhibits transition at 1.06 micrometer Nd:YAG, using nonlinear crystal and Q-switch to double its frequency can attain 0.53 micrometer green beam. In our laser systems, the efficiency at 1.06 micrometer is more than 3 percent, an efficiency of 0.5 percent at 1.32 micrometer and 0.53 micrometer can be attained. For a power of 100w at 1.06 micrometer, 15w at 1.32 micrometer and 0.53 micrometer can therefore be produced. All of three kinds Nd:YAG laser hold these characteristics: high output power; optical fiber transition that can be cooperated with endoscope. The paper mainly discusses laser operating characteristics and clinic applications of three kinds wavelengths at 0.53 micrometer 1.06 micrometer and 1.32 micrometer Nd:YAG laser systems.

Li, Yahua; Li, Zhenjia; Zhu, Changhong; Huang, Yizhong

1996-09-01

160

Um Ambiente para Monitoramento da Morte Súbita dos Citrus  

Microsoft Academic Search

This article describes the implementation and applications of computational-statistical surveillance system for the Citrus Sudden Death Disease. The data is stored in a spatio-temporal TerraLib database and statistical analysis are performed using functions written as a add-on pack- age for the R language called Rcitrus which implements some specialized statistical methods and also interfaces with other packages such as geoR,

Elias Teixeira Krainski; Paulo Justiniano Ribeiro Jr.; Pedro Ribeiro De Andrade Neto; Renato Beozzo Bassanezi

2005-01-01

161

Um Novo Procedimento para o Calculo de Mochilas Compartimentadas  

Microsoft Academic Search

It considers the classic knapsack problem. It admits that items must be grouped in subgroups, and items of a grouping cannot be matched with items of another grouping. The Compartmented Knapsack Problem (CKP) consists of constructing compartments, whose dimensions are limited and must be determined, and where each one of them is formed by items of some grouping. This is

Robinson Hoto; Nelson Maculan; Marcos Arenales; Fabiano Marques

2002-01-01

162

A mulher em situação de abortamento: um enfoque existencial  

Microsoft Academic Search

This work aims at revealing the meaning of abortion in the view of women who have experienced it. For this purpose, the author used the Methodology of Phenomenological Investigation, which enabled a comprehensive analysis of the accounts collected. Data were gathered by interviewing twelve hospitalized women. The following questions were used: \\

Magali Roseira Boemer; Mariana Gondim Mariutti

2003-01-01

163

Multi-waveband analysis of 12um galaxies (Brightman+, 2011)  

NASA Astrophysics Data System (ADS)

We have obtained narrow-line ratios from a compilation of unpublished data from Rodriguez et al. (in preparation) for 70 of the galaxies in our sample of 126 sources. For the rest, where they exist, we have compiled from the literature the [OIII]/H?, [OI]/H?, [NII]/H? and [SII]/H? line ratios which are needed for this classification method. In five cases we have used SDSS DR7 emission-line data, where no literature line ratio data exist. (2 data files).

Brightman, M.; Nandra, K.

2012-02-01

164

DESENVOLVIMENTO DE UM HIDROMETRO ELETRÔNICO DE BAIXO CUSTO  

Microsoft Academic Search

The reduction in the world readiness of drinking water is demanding a new conscience from the population in relation to the use of that resource, indispensable for the accomplishment of the human activities and for our survival. In Brazil the auto- mation begins to be used in the basic services of drinkable water supply, with the main goal being the

IVO R. FONTES; JOSÉ A. CAGNON; FELIPE M. BASTOS; MICHEL C. MALARA; ANDRÉ L. ANDREOLI

165

12 UM Contribution of Nearby Galaxies to the Infrared Background.  

National Technical Information Service (NTIS)

There were twelve publications in the final with the emphasis on the study of blue compact galaxies. The blue compact dwarf galaxy He 2-10 has been observed in the mid-IR. The central regions contained two resolved components which have the same mid-IR pr...

T. X. Thuan

1994-01-01

166

Overtone CO laser (lambda = 2.5-4.2 um)  

Microsoft Academic Search

A survey of experimental and theoretical results on physics of a CO laser operating on first-overtone (FO) vibrational transitions V plus 2 implies V is presented. A special attention is paid to quite new results recently obtained at the P. N. Lebedev Physics Institute (Russia), TRINITI (Russia) and Air Force Research Lab. (USA). Efficient multiwavelength pulsed FO CO lasing with

Andrei A. Ionin

2002-01-01

167

Um modelo de crescimento liderado pelas exportações com restrição financeira  

Microsoft Academic Search

The present paper intends to demonstrate, on the other hand, as the growth of the economy can be led by the exportations and, for another one, as such growth can have a external restriction of financial order for countries that present a deficit structural rigidity in the relation of commerce with the remaining portion of the world. Front to such

Marcos Adolfo; Ribeiro Ferrari

2005-01-01

168

Desenvolvimento de aplicações educativas em Geologia - Um exemplo  

Microsoft Academic Search

Resumo - Face à quase total inexistência de microscópios petrográficos nas escolas portuguesas dos ensinos básico e secundário, os alunos destes graus de ensino vêm-se privados do contacto com uma das técnicas básicas de observação e caracterização dos materiais geológicos. Para obviar esta lacuna iniciou-se a produção de uma aplicação multimédia, a ser disponibilizada on-line e off-line, com recurso a

J. B. R. Brilha; R. Henriques

169

INFLUÊNCIAS HISTÓRICAS NA CULTURA LITERÁRIA Um estudo de \\  

Microsoft Academic Search

The present work, result of researches and analyses, was idealized as an instrument to understand the influence historical contexts exert on the construction of sense of literary cultural production. Based on the knowledge of historical panorama of East Timor, in the period of Indonesian invasion, and Brazil's, during military dictatorship, the purpose of this work was to analyze the work

Chico Buarque

170

The First Low uM SecA Inhibitors  

PubMed Central

SecA ATPase is a critical member of the Sec family, which is important in the translocation of membrane and secreted polypeptides/proteins in bacteria. Small molecule inhibitors can be very useful research tools as well as leads for future antimicrobial agent development. Based on previous virtual screening work, we optimized the structures of two hit compounds and obtained SecA ATPase inhibitors with IC50 in the single digit micromolar range. These represent the first low micromolar synthetic inhibitors of bacterial SecA and will be very useful for mechanistic studies.

Chen, Weixuan; Huang, Ying-ju; Gundala, Sushma Reddy; Yang, Hsiuchin; Li, Minyong; Tai, Phang C.; Wang, Binghe

2010-01-01

171

1-5-um infrared camera of the IAC  

NASA Astrophysics Data System (ADS)

The Instituto de Astrofisica de Canarias (IAC) is undertaking the construction of an IR camera for astronomical use at the 1.5 meter (f/13,8) Carlos Sanchez IR Telescope (CST), sited at the Observatorio del Teide (Tenerife). The camera will employ a 256 X 256 InSb focal plane array, and will be used in the 1 - 5 micron atmospheric windows. The Camera uses an optical reimaging system which maps 0.5 square arcseconds of sky per pixel. The optical system will be diamond turned in aluminum and mounted in such a way that the optical alignment is facilitated. Two filter wheels will accommodate 14 broad and narrow band filters. A SUN SPARCstation will control the camera and allow data handling and displaying of the images. With this configuration we expect to achieve sensitivities of 17 and 12.5 magnitude (3 (sigma) in 10 sec) at the K and L band respectively.

Gonzalez, Juan C.; Acosta, J. D.; Diaz, Jose J.; Fuentes, F. Javier; Fuensalida, Jesus J.; Hammersley, Peter; Joven-Alvarez, Enrique; Mampaso, A.; Manescau, Antonio; Martin, Carlos; Paez, E.; Espinosa, Jose M.; Rodriguez-Mora, A.; Rodriguez-Ramos, Luis F.; Sanchez, Vicente; Selby, M.; Sosa, Nicolas A.

1993-10-01

172

Measurement of filter attenuation in the 10-um region  

NASA Astrophysics Data System (ADS)

IR imaging sensors are generally designed to be as sensitive as possible. This makes them vulnerable to dazzle and damage by attack from in-band lasers. An obvious method of protecting these sensors is to include rejection filters in the optical system. The required rejection ratio may be many orders of magnitude. Of particular interest is the possible application of rejection filters to protect thermal imagers. Some difficulties have been experienced in the laboratory measurement of the rejection ratio of such filters. These problems are explained and methods to overcome them are discussed so leading to a reliable method of measurement.

Kent, Malcolm J.

1999-12-01

173

2.7-um diode-pumped fiber laser  

Microsoft Academic Search

The performances of the diode-pumped 2.7 micrometers fiber laser have been studied. From the population inversion estimated for a fluorozircoaluminate (AZF) glass with different ErF3 doping, a higher gain was expected for a higher ErF3 doping. The laser performances were improved by adjusting fiber length. Maximum output power of 18.5 mW and slope efficiency of 7% were obtained by using

Hiroaki Yanagita; Hisayoshi Toratani; Toshiharu T. Yamashita; Isao Masuda

1992-01-01

174

Crianças com dificuldade de aprendizagem: um estudo de seguimento  

Microsoft Academic Search

Considering that learning problems are a vulnerability factor throughout child development, mainly when other adversities are present, this research investigated the association between past conditions and present adjustment in adolescents who have attended a child guidance clinic because of their learning difficulties. The adolescents and their mothers were interviewed and data related to past life conditions were taken from their

Luciana Carla dos Santos; Edna Maria Marturano

1999-01-01

175

Crianças surdas e suas famílias: um panorama geral  

Microsoft Academic Search

Considering the importance of the family to child development, especially to children who have some disability, this paper analysed some aspects of family interactions and relationships developed between such children and their families. We emphasised family interactions because of their influence on the development of the children's relationships in the future, particularly in relation to the deaf child. Thus, the

Angela Maria Waked de Brito; Maria Auxiliadora Dessen

1999-01-01

176

UM-StL 1D Acceleration Solver  

NSDL National Science Digital Library

Produced by the University of Missouri - St. Louis, this website is an educational "resource for solving low and high speed constant acceleration problems." Physics students can find quantitative tools to handle time dilation, relativist acceleration, and curved space-time. Containing networks of numerous concepts dealing with physics, chemistry, and math, the site helps students understand how various concepts fit together. Within this large site, students can find information about SpaceTime theory, Map-based relativity, Lorentz Transforms, and much more.

177

UM-StL 1D Acceleration Solver  

NSDL National Science Digital Library

Produced by the University of Missouri - St. Louis, this website is an educational "resource for solving low and high speed constant acceleration problems." Physics students can find quantitative tools to handle time dilation, relativist acceleration, and curved space-time. Containing networks of numerous concepts dealing with physics, chemistry, and math, the site helps students understand how various concepts fit together. Within this large site, students can find information about SpaceTime theory, Map-based relativity, Lorentz Transforms, and much more.

2007-10-03

178

Kranke, Ströme, Strahlenfelder – Medizin und Elektrizität um 1900  

Microsoft Academic Search

\\u000a Die Beziehungsgeschichte zwischen äußeren Kräften, wundersamen Fluiden oder magnetischen Feldern und der Medizin ist alt.\\u000a Bereits lange vor 1900 hatten beide eine durchaus innige Verbindung konstituiert, die gleichwohl nicht immer frei von Wunderglauben,\\u000a Scharlatanerie und Betrug war. Stellvertretend hierfür mag die Geschichte des Mesmerismus gelten, der zunächst im französischen\\u000a Ancien régime, aber bald auch im revolutionären Frankreich und schließlich in

Wolfgang U. Eckart

179

UM MECANISMO DE CONTROLE ADAPTATIVO COM REQUISITOS DE JUSTI CA  

Microsoft Academic Search

This paper describes an adaptive control scheme for distributed multimedia applications, dealing with the receiver heterogeneity problematic. The controllers are deployed over the network, where all of them participate actively in the adaptation and are synchronized. They adapt the distributed multimedia ow, according to the end-to-end network conditions as percei- ved by the receivers. The adaptation is based on simple

Ricardo Ferreira Martins; Cristian Koliver; Jean-Marie Farines

180

WISE and HIP 22um excess stars (Wu+, 2013)  

NASA Astrophysics Data System (ADS)

In this paper, we present a catalog that includes 141 bright candidates (<=10.27mag, V band) showing an excess of infrared (IR) at 22?m. Of these 141 candidates, 38 stars are known IR-excess stars or disks, 23 stars are double or multiple stars, and 4 are Be stars while the remaining more than 70 stars are identified as 22 ?m excess candidates in our work. The criterion for selecting candidates is Ks-[22]?m. All these candidates are selected from the Wide-field Infrared Survey Explorer all-sky data cross-correlated with the Hipparcos main catalog and the likelihood-ratio technique is employed. Considering the effect of background, we introduce the IRAS 100?m level to exclude the high background. We also estimate the coincidence probability of these sources. In addition, we present the optical to mid-IR spectral energy distributions and optical images for all the candidates, and give the observed optical spectra of six stars with the National Astronomical Observatories, Chinese Academy of Sciences' 2.16m telescope. To measure for the amount of dust around each star, the fractional luminosity is also provided. We also test whether our method of selecting IR-excess stars can be used to search for extra-solar planets; we cross-match our catalog with known IR-excess stars with planets but found no matches. Finally, we give the fraction of stars showing excess IR for different spectral types of main-sequence stars. (2 data files).

Wu, C.-J.; Wu, H.; Lam, M.-I.; Yang, M.; Wen, X.-Q.; Li, S.; Zhang, T.-J.; Gao, L.

2013-11-01

181

8.6um imaging of 47 Tuc (Momany+, 2012)  

NASA Astrophysics Data System (ADS)

Our observations were obtained using the VLT spectrometer and imager for the MIR (VISIR) currently located at the Cassegrain focus of UT3. These observations were carried out in service mode in the period between October 3, 2009 and January 30, 2010. (1 data file).

Momany, Y.; Saviane, I.; Smette, A.; Bayo, A.; Girardi, L.; Marconi, G.; Milone, A. P.; Bressan, A.

2012-03-01

182

Investigation of laser radiation extinction in pyrotechnic aerodispersive clouds at 1.06-um and 10.6-um wavelengths  

NASA Astrophysics Data System (ADS)

In the paper an extinction of the laser radiation at 1.06 and 10.6 micrometers wavelengths in aerosol clouds generated by burning of pyrotechnic mixtures is investigated. The results of transmission measurements and evaluated values of volume attenuation coefficient are presented for a few kinds of chloro-organometallic smoke-producing agents. An estimation of the laser ranging diminution by the pyrotechnic-derived smoke was carried out.

Cudzilo, Stanislaw; Czechowicz, Roman; Noga, Janusz; Paplinski, Andrzej; Wlodarczyk, Edward

1995-03-01

183

Diode-pumped erbium lasers at 1.55 um and 1.64 um in single-frequency operation  

Microsoft Academic Search

Single frequency operation of a diode pumped Er:YAG laser at 1.64 micrometers was achieved first time with a new type of halfmonolithic lasers in a cleaved coupled cavity (C3). A single frequency Er:YAG-Er:glass-sandwich laser in C3-design was realized as well. Single frequency operation of the Er:glass laser is also achieved with a thin metal film and a tilted Fabry-Perot etalon

S. Nikolov; Ludwig Wetenkamp

1996-01-01

184

Diode-pumped erbium lasers at 1.55 um and 1.64 um in single-frequency operation  

NASA Astrophysics Data System (ADS)

Single frequency operation of a diode pumped Er:YAG laser at 1.64 micrometers was achieved first time with a new type of halfmonolithic lasers in a cleaved coupled cavity (C3). A single frequency Er:YAG-Er:glass-sandwich laser in C3-design was realized as well. Single frequency operation of the Er:glass laser is also achieved with a thin metal film and a tilted Fabry-Perot etalon as mode selective elements. The tuning range of Er:glass can be extended up to 1560 nm by a special mirror coating. Eye safe erbium lasers are very important for different applications in optical communication and lidar techniques, e.g. due to their coincidence with the attenuation minimum of glass fibers at 1.55 micrometers (Er:Yb:glass laser) and with the methane absorption line at 1.64 micrometers (Er:YAG laser).

Nikolov, S.; Wetenkamp, Ludwig

1996-04-01

185

High-resolution superconducting x-ray spectrometers with an active area of 282 um x 282 um  

SciTech Connect

Superconducting tunnel junctions coupled to superconducting absorbers may be used as high-resolution, high-efficiency X-ray spectrometers. We have tested devices with niobium X-ray absorbing layers coupled to aluminum layers that serve as quasiparticle traps. In this work we measured the current pulses from a large area tunnel junction using an amplifier based on an array of 100 SQUIDs. Using this amplifier and a 282 micron X 282 micron junction, we have measured an energy resolution of 19 eV FWHM for 1.5 keV X rays and 21 eV for 2.6 keV X rays. The area of this junction is eight times the area of any junction previously measured to have such high energy resolution.

Mears, C.A.; Labov, S.E.; Frank, M.; Netel, H.; Hiller, L.J.; Lindeman, M.A.; Chow, D.; Barfknecht, A.T.

1996-09-11

186

El problema de la barrera linguistica en el desarrollo cientifico y tecnologico (The Problem of the Language Barrier in Scientific and Technological Development).  

ERIC Educational Resources Information Center

This monograph discusses the problem of the language barrier in scientific and technological development in terms of several parameters describing the flow of scientific information from one language to another. The numerical values of the language barrier parameters of the model are calculated in the field of information on second language…

Zierer, Ernesto

187

Frozen Soil: A Material to Solve Problems in the Construction Industry (Suelo Congelado: Un Material para la So Lucion do Problemas en la Industria de la Construccion).  

National Technical Information Service (NTIS)

Digging a well, restoring the foundations of a building or digging a tunnel in the soils of big cities constitute difficult projects due to a large number of already existing pipelines and sewers. When the city has a clayey subsoil with some content of wa...

J. A. Careaga E. R. Mayer

1975-01-01

188

Solucoes Aproximadas para o Problema de Localizacao Simples. Algorithmo Simulated Annealing (Approximative Solutions for the Simple Plant Location Problem. Simulated Annealing Algorithm).  

National Technical Information Service (NTIS)

The Simple Plant Location (SPL) is a NP-hard problem that arises in a great variety of real world situations. Given a finite set of possible locations for establishing new facilities, SPL deals with the supply of a single commodity from a subset of these ...

M. Leonor de Almeida Gouveia Oliveira

1991-01-01

189

Temas y Problemas del idioma espanol en la prensa: El lenguaje, arma peligrosa (Themes and Problems of the Spanish Language in the Press: Language, a Dangerous Weapon).  

ERIC Educational Resources Information Center

Discusses the important role that language has in our society and compares human communication to animal group communication. Gives specific examples of corruption in the Spanish language today. (NCR)

de Senillosa, Antonio

1979-01-01

190

Problemas del Lenguaje Espanol en la Prensa: El Castellano, Esta Lengua Enferma (Problems of the Spanish Language in the Press: Castillian, That Closed-In Language)  

ERIC Educational Resources Information Center

Learned academies deplore the deterioration of Castillian Spanish due to foreign contamination. They ignore the real source of the problem within Spain itself where everyone speaks the language badly except those in the remote towns and a few intellectuals. A ray of hope comes from the Americans. (Text is in Spanish.) (AMH)

Quijada, Carlos Alonso

1977-01-01

191

Datirovka zvezdnogo kataloga Ptolemeya po sobstvennym dvizheniyam: tysyacheletnyaya problema reshena %t Dating Ptolemy's star catalogue based on proper motions: the thousand-year-old problem solved  

NASA Astrophysics Data System (ADS)

The thousand-year-old problem of the origin of the star catalogue included in Ptolemy's "Almagest" is considered. The dilemma whether stellar coordinates were based on Hipparchus' or Ptolemy's observations has arisen long ago, because the 1 degree error in ecliptic longitudes may be explained either by Ptolemy's error in the initial longitudes of the Sun, or by the fact that Ptolemy adopted the original Hipparchus' coordinates and transformed them to a 265-year later epoch using an erroneous constant for precession. In fact, only indirect evidence for the Hipparchan origin of most of the coordinates was available so far, and most specialists considered the issue still to be resolved. We have successfully applied a new approach based on stellar proper motions. The time-dependent mutual distances in the configurations including 8 fast stars yield an epoch of -53 ± 130 B.C., whereas the bulk method based on an analysis of the Almagest minus computed coordinate differences for 40 fastest stars yields an epoch of -90 ± 120 B.C. Standard errors in the ancient ecliptic longitudes and latitudes are found to be ?(?cos?) = 18' and ?? = 13', respectively. It is concluded that the stellar coordinates in the Almagest catalogue were observed during Hipparchus' lifetime and that Ptolemy's authorship claim can be rejected at a 94% significance level. Ptolemy's assertion that "we observed as many stars as we could sight down to the sixth magnitude" might simply imply that he found each star of the original catalogue to be near its position in the sky given by Hipparchus, and then adopted Hipparchus' coordinates as measured by a more skilled observer.

Dambis, A. K.; Efremov, Yu. N.

192

Use of Simulation Techniques in the Problem of Air Traffic Control l'USO Delle Tecniche di Simulazione Nel Problema Del Controllo Del Traffico Aereo.  

National Technical Information Service (NTIS)

The air-traffic control involves a series of necessarily interconnected problems, whose solution needs a charged system to work out the information and to plan the decisions with coordination. The use of simulation techniques with which the system is divi...

C. Bottiglieri A. Dicola

1976-01-01

193

`Why Can't They Do Anything for a Simple Back Problem?'A Qualitative Examination of Expectations for Low Back Pain Treatment and Outcome  

Microsoft Academic Search

In order to examine expectations for pain treatment and outcome and to determine whether they are influential in maintaining health service consumption 16 adults suffering from chronic pain were interviewed. Transcripts were subjected to thematic analysis. The six main themes to emerge were labelled: Unmet Expectations; Health Professionals; the Importance of Self; Getting Something Done; Back to Square One; and

Carol Campbell; Alison Guy

2007-01-01

194

Uncovering the Essence of the Climate Change Adaptation Problem—A Case Study of the Tourism Sector at Alpine Shire, Victoria, Australia  

Microsoft Academic Search

A problem-orientated and interdisciplinary approach was employed at Alpine Shire, in north-east Victoria, Australia, to explore the concept of contextual vulnerability and adaptability to stressors that include, but are not limited to climatic change. Using a policy sciences approach, the objective was to identify factors that influence existing vulnerabilities that might consequently act as barriers to effective adaptation for the

Carolina E. Roman; Amanda H. Lynch; Dale Dominey-Howes

2010-01-01

195

Evite los problemas de la diabetes: Mantenga sano el sistema nervioso (Prevent Diabetes Problems: Keep Your Nervous System Healthy, Number 6 in a Series of 7).  

National Technical Information Service (NTIS)

Too much glucose (sugar) in the blood for a long time can cause diabetes problems. This high blood glucose (also called blood sugar) can damage many parts of the body, such as the heart, blood vessels, eyes, and kidneys. Heart and blood vessel disease can...

2003-01-01

196

Hacia Una Pedagogia de Solucion de Problemas en La Educacion Ambiental. Serie Educacion Ambiental 15 (Pedagogy of Solutions and Problems in Environmental Education. Environmental Education Series 15.  

ERIC Educational Resources Information Center

This document discusses the teaching of problem solving in environmental education. From an interdisciplinary viewpoint, this study describes some strategies for teaching that can favor the practice of educational activities oriented toward solving the concrete problems of the surrounding environment. The volume is divided into seven chapters. The…

United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.

197

Comparing the use of 4.6 um lasers versus 10.6 um lasers for mitigating damage site growth on fused silica surfaces  

SciTech Connect

The advantage of using mid-infrared (IR) 4.6 {micro}m lasers, versus far-infrared 10.6 {micro}m lasers, for mitigating damage growth on fused silica is investigated. In contrast to fused silica's high absorption at 10.6 {micro}m, silica absorption at 4.6 {micro}m is two orders of magnitude less. The much reduced absorption at 4.6 {micro}m enables deep heat penetration into fused silica when it is heated using the mid-IR laser, which in turn leads to more effective mitigation of damage sites with deep cracks. The advantage of using mid-IR versus far-IR laser for damage growth mitigation under non-evaporative condition is quantified by defining a figure of merit (FOM) that relates the crack healing depth to laser power required. Based on our FOM, we show that for damage cracks up to at least 500 {micro}m in depth, mitigation using a 4.6 {micro}m mid-IR laser is more efficient than mitigation using a 10.6 {micro}m far-IR laser.

Yang, S T; Matthews, M J; Elhadj, S; Cooke, D; Guss, G M; Draggoo, V G; Wegner, P J

2010-10-21

198

Desenvolvimento de Um Sistema Grafico: Um Exemplo No Tracado de Cartas Sinoticas (Development of a Graphic System: Example Using the Outline of Synoptic Charts).  

National Technical Information Service (NTIS)

A system, SINOGRAFO, is described that was developed to trace synoptic charts based on the display of meteorological data for the Brazilian Institute of Space Research. SONOGRAFO was used to trace the contour of South America and international boundaries ...

S. R. M. Pellegrino J. A. G. Pereira

1984-01-01

199

Mild steels coated with 14% manganese covered electrodes (E7UM200-K and E1UM350): Phenomena at the steel-coating interface  

Microsoft Academic Search

In this work the authors have studied the phenomena in the interface of the coating made on soft carbon steel with electrodes with a high content of manganese. The study has been done with scanning electron microscope and X-rays mapping images. These images show how the alloy elements are distributed in each of the constituent elements presented in the interface,

F.. Molleda; J. Mora; E. Carrillo; E. Mora; B. G. Mellor

2006-01-01

200

Análise dos Conceitos Astronômicos Apresentados por Professores de Algumas Escolas Estaduais Brasileiras  

NASA Astrophysics Data System (ADS)

A razão para o desenvolvimento deste trabalho baseia-se no fato de que muitos professores da Educação Básica (EB) não lidam com conceitos relacionados à astronomia, e quando o fazem eles simplesmente seguem livros didáticos que podem conter erros conceituais. Como é de conhecimento geral a astronomia é um dos conteúdos a serem ensinados na EB fazendo parte dos Parâmetros Curriculares Nacionais e das Propostas Curriculares do Estado de São Paulo, mas é um fato, que vários pesquisadores apontam, a existência de muitos problemas no ensino da astronomia. Com o propósito de minimizar algumas dessas deficiências foi realizado um trabalho de pesquisa com a utilização de questionários pré e pós pesquisa, para tanto foi desenvolvido um Curso de Extensão Universitária para professores da Diretoria de Ensino Regional (DE) que abrange Mauá, Ribeirão Pires e Rio Grande da Serra (no Estado de São Paulo) com os seguintes objetivos: levantar concepções alternativas; subsidiar os professores por meio de palestras, debates e workshops, e verificar o sucesso da aprendizagem após o curso, adotando-se como referência, para a análise dos resultados, os dicionários de Língua Portuguesa (FERREIRA, 2004) e Enciclopédico de Astronomia e Astronáutica (MOUR?O, 1995). Portanto, dezesseis questões foram aplicadas antes e após o curso, assim pode-se verificar após a pesquisa que 100,0% dos professores sabiam os nomes das fases da Lua, 97,0% entenderam que o Sistema Solar é composto por oito planetas, 78,1% foram capazes de explicar como ocorre um eclipse lunar, um eclipse solar e um solstício, 72,7% sabiam como explicar a ocorrência das estações do ano; 64,5% explicaram corretamente a ocorrência do equinócio, 89,7% foram capazes de definir adequadamente o termo cometa; 63,6% definiram asteróide, 54,5% meteoro, 58,1% galáxia, e 42,4% planeta. Os resultados obtidos indicam uma aprendizagem significativa por parte dos participantes.

Voelzke, Marcos Rincon; Gonzaga, Edson Pereira

2011-12-01

201

Government policies and deforestation in Brazil's Amazon region  

SciTech Connect

Contents include: Brazil's Amazonian Forests (biological diversity, the magnitude and rate of deforestation, proximate causes of deforestation); and the evolution of regional policies (operation Amazonia, the Belem-Brasilia Highway, incentives for livestock development, the National Integration Program, the Cuiaba-Porto Velho Highway and Polonoroeste, the era of big projects).

Mahar, D.J.

1989-01-01

202

CUESTIONARIO BREVE DE TAMIZAJE Y DIAGNÓSTICO DE PROBLEMAS DE SALUD MENTAL EN NIÑOS Y ADOLESCEN- TES: ALGORITMOS PARA SÍNDROMES Y SU PREVALENCIA EN LA CIUDAD DE MÉXICO. SEGUNDA PARTE  

Microsoft Academic Search

and ICD-10 classifications. Based on these results, algorithms for probable psychiatric syndromes were created. Results Using the results from logistic regression analyses, algorithms were created considering different levels of severity for probable disor- ders: attention-deficit and hyperactivity distinguishing three subtypes, depressive with two definitions and two severity degrees, anxiety with two subtypes, oppositional behavior, conduct disorder, spe- cific language disorder,

Jorge Javier Caraveo

2007-01-01

203

A área de proteção ambiental 'Fazenda e Parque do Carmo': os problemas ambientais, as dificuldades de gestão e a influência na qualidade de vida da população The environmental protection area \\  

Microsoft Academic Search

RESUMO: A falta de planejamento urbano da Cidade de São Paulo contribuiu para a eliminação da maior parte da cobertura vegetal, dada à ocupação irregular, inclusive de áreas legalmente protegidas. Essas áreas verdes são reguladoras do equilíbrio ambiental e assim, interferem diretamente na qualidade de vida da população. Através de levantamento bibliográfico e documental e entrevista com o Conselho Consultivo

Mirtes Moreira Silva; José Luís Negrão Mucci; Maria Cecília Focesi Pelicioni

204

AS DOENÇAS SEXUALMENTE TRANSMISSÍVEIS SÃO PROBLEMAS ENTRE GESTANTES NO CEARÁ? ARE SEXUALLY TRANSMITTED DISEASES A PROBLEM TO PREGNANT WOMEN IN CEARÁ? MENÇÃO HONROSA - PRÊMIO MELHOR TRABALHO COMPLETO, CATEGORIA: EPIDEMIOLOGIA  

Microsoft Academic Search

Introduction: the complications of STD (Sexually Transmitted Diseases) include ectopic pregnancy, spontaneous abortions, stillbirth, prematurity, conge- nital perinatal and puerperal infection. In Brazil, studies in pregnant women are scarce, although STD have an important impact in pregnancy outcome. Objective: to estimate the prevalence of syphilis, gonorrhea, chlamydeous, and trichomoniasis in pregnant women in two municipalities of Ceará and to identify

Telma A Martins; Pierre Y-Bello; Martha D Bello; Lígia Regina; SK Pontes; Lúcia V Costa; Iracema S Miralles; Telma Régia

205

Memoria de calculo e simulacao do 2(sup 0) problema padrao da AIEA com o codigo Trac/PF1. (Input data preparation and simulation of the second standard problem of IAEA using the Trac/PF1 code).  

National Technical Information Service (NTIS)

The second Standard Problem sponsored by IAEA consists in the simulation of a small LOCA located in the downcomer of a PMK-NVH integral test facility, which models WWER/440 type reactor. This report presents input data preparation and comparison between T...

A. A. Madeira A. C. Pontedeiro M. R. Silva Galetti R. C. Borges

1989-01-01

206

Cooperazione Scientifica Italia (ISS) Ecuador (IFA). La Prevenzione Delle Patologie da Amianto: un Problema di Sanita Pubblica. (Scientific Cooperation Between Italy (ISS) and Ecuador (IFA). The Prevention of Asbestos-Related Diseases: a Public Health Concern.)  

National Technical Information Service (NTIS)

This report is aimed at discussing the health impact caused by asbestos exposure in the workplace as well as in the general environment. The report relies on a working hypothesis aimed at promoting contrast measures based on scientific evidence and intern...

D. Marsili P. Comba R. Harari

2009-01-01

207

Atención a la familia: otra forma de enfocar los problemas de salud en atención primaria. Instrumentos de abordaje familiar Taking account of the family: another form of focussing on health problems in primary care. Instruments of the family approach  

Microsoft Academic Search

On many occasions somatic symptoms that do not improve with conventional measures reflect hidden problems related to the patient's milieu, and this milieu is usually the family. But the family is not only what makes it possible to understand the problems, it is also a resource of incalculable value for attending to health problems in a global form, and for

I. Yurss

208

Estudo e aplicacao de codigos nucleares disponiveis no Ipen em problemas de fisica de reatores dependentes do tempo. (Study of reactor analysis code available at Ipen and their application to the time dependent problems).  

National Technical Information Service (NTIS)

Two computer codes available at IPEN are studied and applied to analyze time-dependent problems of nuclear reactors. The GAPOTKIN code can be used to analyze short-term transient behaviours and the CITATION code is applicable to long-term burnup analysis....

M. Yamaguchi

1989-01-01

209

Nine Tips To Help Faith Leaders and Their Communities Address Teen Pregnancy = Nueve consejos para ayudar a lideres espirituales y sus comunidades a hacerle frente al problema del embarazo en la adolescencia.  

ERIC Educational Resources Information Center

To support faith communities in protecting teenage boys and girls from too-early sexual activity and teen pregnancy, the National Campaign To Prevent Teen Pregnancy's Task Force on Religion and Public Values has compiled these nine tips which summarize a wealth of experience and advice from faith leaders around the country. The members of the Task…

National Campaign To Prevent Teen Pregnancy, Washington, DC.

210

A experiência da Universidade São Francisco com o internato médico de psiquiatria utilizando a metodologia da aprendizagem baseada em problemas The experience of Universidade São Francisco with the medical internship in psychiatry using the problem-based learning method  

Microsoft Academic Search

In the last few years, medical education has been going through curricular and pedagogical changes with the purpose of educating a new health professional. One of the pedagogical alternatives is the education based on problem-solving, which works essentially with the construction of knowledge using signifi cant experiences. Such learning model has enabled curricular changes, which, in the fi eld of

Fernando Ribeiro da Silva Paulin; Regina Caeli; Guerra Poças; Bragança Paulista

2009-01-01

211

Some Aspects of the Problems of the Average Life of Erythrocytes with the Use of Cr51 Radioactive Sodium Chromate; ALGUNS ASPECTOS DO PROBLEMA DA DETERMINACAO DA VIDA MEDIA DOS ERITROCITOS COM O EMPREGO DO Cr51 (RADIOCROMATO DE SODIO)  

Microsoft Academic Search

Analytical expressions were derived for the survival curves of Cr⁵¹; -labeled erythrocytes. Expressions are obtained for normal erythrocytes, ; normal erythrocytes transfused into receptors containing a lethal factor, ; erythrocytes subjected to a lethal factor after formation, and potentially ; immortal erythrocytes subjected to an exterior lethal factor which destroys them ; randomly, regardless of age. (J.S.R.);

Pieroni

1959-01-01

212

International meeting. Complexity in the Living: A Problem-Oriented Approach. Rome, September 28-30, 2004. (Convegno internazionale. La Complessita del Vivente: un Approccio Orientato al Problema. Roma, 28-30 Settembre 2004).  

National Technical Information Service (NTIS)

The scientific world has the clear perception that an interdisciplinary approach is urgently needed for attacking the many yet unsolved problems of today science. This attitude has several roots, including the search of biologists for quantitative foundat...

A. Colosimo A. Giuliani J. P. Zbilut P. Sirabella R. Benigni

2005-01-01

213

Nonlinear optical properties of semiconductor quantum well structures near 1.55 um  

Microsoft Academic Search

We present an experimental study of mode-locking in linear- cavity erbium-doped fiber lasers which use MQW mirrors as saturable reflectors. From the results of single-beam, nonlinear transmission measurements, we have found the saturation intensity of the MQW mirrors to be greatly dependent on the wavelength of the incident radiation with respect to the MQW bandedge. For satisfactory mode-locked laser performance,

Mark F. Krol; Michael J. Hayduk; Steven T. Johns; Kenneth J. Teegarden; Gary W. Wicks

1996-01-01

214

High-magnification zoom lenses for 3- to 5-um applications  

NASA Astrophysics Data System (ADS)

Over the past twenty years numerous papers and patents have reported on the design of infrared zoom lenses for a variety of civilian and military applications. The vast majority of these lenses have been afocal 8 - 12 micrometer zoom lenses with magnification ratios of five to twenty. With the advancement of 3 - 5 micrometer staring focal plane array technology a growing demand has emerged for a compact imaging 3 - 5 micrometer zoom lens. To meet this demand a variety of such zoom lenses have been designed which support image formats of over 10 mm diagonal. In this paper the preliminary design of a high magnification 3 - 5 micrometer zoom lens is described. Infrared system modeling, detailed lens performance and manufacturing issues are reviewed.

Sinclair, R. Lawrence

1998-10-01

215

Infixation and segmental constraint effects: UM and IN in Tagalog, Chamorro, and Toba Batak  

Microsoft Academic Search

The proper understanding of infixation continues to be a matter of debate among linguists. The data presented in this paper show that infixation in Austronesian languages is not exclusively due to Prosodic Morphology, but instead is significantly influenced by the segmental phonology as well. Specifically, infixation may be blocked if it would create dissimilation environments in the first bimoraic foot

Thomas B. Klein

2005-01-01

216

"I May Be Crackin', But Um Fackin": Racial Humor in "The Watsons Go To Birmingham--1963"  

ERIC Educational Resources Information Center

This article examines the utilization of racial humor in Christopher Paul Curtis' novel, "The Watsons Go To Birmingham--1963." The theoretical perspectives that inform the analysis include critical race theory and humor theory. The results of the analysis reveal that the use of humor in this book is influenced to a significant degree by race and…

McNair, Jonda C.

2008-01-01

217

The impact of atmospheric waves on the O2 1.27-um nightglow distribution  

NASA Astrophysics Data System (ADS)

O2 -1.27µm nightglow is the indicator of the general circulation at about 95 km in Venus. Recent nightglow observations reported that the nightglow emission showed the temporal variations with a timescale of a few hours and days [e.g.,Gerard et al., 2008]. The temporal variations are thought to be caused by wind fluctuations due to atmospheric waves propagating from the lower atmosphere. In recent years, the importance of planetary-scale waves on the general circulation of the Venusian atmosphere has been recognized. Forbes and Konopliv [2007] suggested the propagation of planetary-scale waves originated in the cloud deck into the upper atmosphere. However, the impact of the planetary-scale waves on the Venusian upper atmosphere has not been investigated yet. In this study, we have performed numerical simulations with a general circulation model (GCM), which includes the altitude region of 80 -about 200 km in order to understand the impact of atmospheric waves on the nightglow distribution. Our model considers the chemical processes and calculates the O2 -1.27µm nightglow intensity. The planetary-scale waves (thermal tides, Kelvin wave, and Rosbby wave) are imposed at the lower boundary. The amplitudes and phase velocities of the waves are assumed from the study by Del Genio and Rossow [1990]. The simulation results show dominance of the Kelvin wave at about 80 -120 km with a vertical wavelength of about 40 -50 km. The amplitude of the zonal wind fluctuation caused by the Kelvin wave has a maximum value of about 9 m/s at about 95 km. Our results suggest that the Kelvin wave would cause the wind variation of the nightglow emission region between the 00:00LT -00:40LT with a period of 4 days. In this presentation, we will show the details of our simulation results considering the planetary-scale waves. In addition, we will present the initial results of a simulation considering the small-scale gravity wave.

Hoshino, Naoya; Fujiwara, Hitoshi; Takagi, Masahiro; Kasaba, Yasumasa; Takahashi, Yukihiro

218

Arquitectura de um Multiprocessador Orientado para Objectos (Architecture of an Object Oriented Multiprocessor).  

National Technical Information Service (NTIS)

The parallel computer architectures group from INESC conceived a multi-user, extensible architecture, named DICE, with support at hardware level for an object oriented language. This architecture merges in a single chassis, the resources of a workstation ...

P. N. Ferreira da Rosa da Cruz Diniz

1991-01-01

219

Lasers, waveguides and fibers for 3.0-um medical applications  

NASA Astrophysics Data System (ADS)

In the last few years, there has been an increasing interest for the 3.0 micrometers laser radiation, as this wavelength is very strongly absorbed by the water and the other components of soft and hard tissue, in various medical applications, as soft tissue treatment, atherosclerotic plagues removal, treatment of eye lenses, vitreous surgery, hard tissue treatment, bone cutting and drilling, dentistry applications, etc. For all these medical applications reliable lasers emitting in the 3.0 micrometers wavelength range are needed and thus an intensive development effort is going on throughout the world. Our laser development effort, with the Er:YAG and the HF lasers, the only lasers emitting in the 3.0 micrometers wavelength part of the spectrum, in N.T.U.A., is briefly described in this article. For each one of the above possible medical applications, a demand for good flexible delivery systems, for pulsed Er:YAG or continuous wave and pulsed HF laser radiation arises. Several research groups around the world have suggested some possible solutions and among them are sapphire fibers, zirconium fluoride glasses, hollow metallic waveguides, hollow dielectric waveguides, hollow plastic waveguides, etc. In this paper we present the transmission properties of dielectric coated silver hollow glass waveguides fabricated in Japan, dielectric coated quartz waveguides and hollow plastic waveguides fabricated in Israel, sapphire fibers fabricated in USA, and fluoride glass fibers fabricated in France, we compare their straight and bent loss characteristics and we discuss their potential in the above mentioned medical applications.

Serafetinides, Alexander A.; Papayannis, Alexander D.; Fabrikesi, E. T.; Rickwood, Kenneth R.; Wang, You; Shi, Yi-Wei; Miyagi, Mitsunobu; Croitoru, Nathan I.; Harrington, James A.; Nubling, R.

1998-07-01

220

Distribution of benthic foraminifers (>125 um) in the surface sediments of the Arctic Ocean  

USGS Publications Warehouse

Census data on benthic foraminifers (>125 ?m) in surface sediment samples from 49 box cores are used to define four depth-controlled biofacies, which will aid in the paleoceanographic reconstruction of the Arctic Ocean. The shelf biofacies contains a mix of shallow-water calcareous and agglutinated species from the continental shelves of the Beaufort and Chukchi Seas and reflects the variable sedimentologic and oceanic conditions of the Arctic shelves. The intermediate-depth calcareous biofacies, found between 500 and 1,100 meters water depth (mwd), contains abundant Cassidulina teretis , presumably indicating the influence of Atlantic-derived water at this depth. In water depths between 1,100 and 3,500 m, a deepwater calcareous biofacies contains abundant Oridorsalis umbonatus . Below 3,500 mwd, the deepwater mixed calcareous/agglutinated biofacies of the Canada, Makarov, and Eurasian Basins reflects a combination of low productivity, dissolution, and sediment transport. Two other benthic foraminiferal species show specific environmental preferences. Fontbotia wuellerstorfi has a depth distribution between 900 and 3,500 mwd, but maximum abundance occurs in the region of the Mendeleyev Ridge. The elevated abundance of F. wuellerstorfi may be related to increased food supply carried by a branch of Atlantic water that crosses the Lomonosov Ridge near the Russian Continental Shelf. Triloculina frigida is recognized to be a species preferring lower slope sediments commonly disturbed by turbidites and bottom currents. INTRODUCTION At present, our understanding of the Arctic Ocean lags behind our understanding of other oceans, and fundamental questions still exist about its role in and response to global climate change. The Arctic Ocean is particularly sensitive to climatic fluctuations because small changes in the amounts of sea-ice cover can alter global albedo and thermohaline circulation (Aagaard and Carmack, 1994). Numerous questions still exist regarding the nature and timing of paleoclimatic events in the Arctic Ocean. In order to attempt to answer some of these questions, baseline studies are imperative. This report discusses the distribution of benthic foraminifers in surface sediment samples from 49 box cores (figs. 1 and 2, table 1) collected by the U.S. Geological Survey (USGS) with the assistance of the U.S. Coast Guard (USCG). A modern data set of benthic foraminiferal distribution is necessary for interpreting the paleoclimatic and oceanographic history of the Arctic Ocean.

Osterman, Lisa E.; Poore, Richard Z.; Foley, Kevin M.

1999-01-01

221

O uso prolongado de benzodiazepínicos em mulheres de um centro de convivência para idosos  

Microsoft Academic Search

While experts recommend caution against long-term benzodiazepine use in the elder- ly, survey data suggests that the use of benzodiazepine increase with age. The patterns of benzo- diazepine use and factors associated with long-term use in population at risk were studied with a standarlized questionnaire applied to 634 women over 60, who attended a daycare center for older people in

Gisele Huf; Claudia de Souza Lopes; Suely Rozenfeld

2000-01-01

222

Aplicação de gesso agrícola e especiação iônica da solução de um Latossolo sob sistema plantio direto  

Microsoft Academic Search

Low Ca content and Al toxicity are important limitations for yield crops in Brazilian acids soils. Gypsum application may increase Ca contents and decrease Al toxicity. However, a better knowledge of the effects of gypsum on the ionic speciation of soil solution is very important. The ionic speciation of the soil solution (water extract 1:1) was evaluated in samples from

Fernando César; Bachiega ZambrosiI; Luís Reynaldo; Eduardo Fávero

223

Resultados Geofísicos Integrados de um Corpo com Geometria 3D sem Manifestação Superficial  

Microsoft Academic Search

Airborne geophysical data of the SP-RJ survey carried out by the Brazilian Geological Survey (CPRM) reveal a magnetic anomaly without geological expression at the surface. The anomalous features are similar to those associated with alkaline complexes that outcrop in the same region. The absence of surface elements motivated the use of different geophysical methods to characterize the magnetic anomaly source.

André Rugenski; Marta Silvia; Maria Mantovani; Wladimir Shukowsky

224

Improved design and prototyping for a 10\\/20-um camera\\/spectrometer for ESO's VLT  

Microsoft Academic Search

The Cassegrain focus of the 2nd unit telescope of ESO's VLT shall be equipped with a 10\\/20 micrometers camera spectrometer. This instrument shall be built by a consortium of institutes from ESO's member-states responsible for the final design. Still rather detailed internal studies were required to assess the overall scope of work, the repercussions on the telescope design and the

Hans U. Kaeufl; Bernard Delabre

1994-01-01

225

Einwanderungspolitik: Ein Wettlauf um Skills - die Praxis Australiens, Neuseelands, Kanadas und der USA  

Microsoft Academic Search

Die Zuwanderungsdiskussion in Deutschland ist in Bewegung geraten. Durch die so genannte Green-Card-lnitiative können lT-Spezialisten aus Nicht-EU-Staaten seit jüngster Zeit ohne besonderen Visumsantrag befristet nach Deutschland kommen. Darüber hinaus wurde eine unabhängige Kommission »Zuwanderung« eingesetzt, die konkrete Empfehlungen für eine zukünftige Zuwanderungspolitik erarbeiten soll. Für die anstehende Diskussion in Deutschland dürfte es von Interesse sein, wie andere Länder ihre Zuwanderungspolitik

Wolfgang Ochel

2000-01-01

226

Effect of cirrus clouds in the infrared (4 to 100 um): high-spectral-resolution simulations  

Microsoft Academic Search

The effect of cirrus clouds in the IR has been simulated at high spectral resolution and the sensitivity to crystal, size, aspect ratio, size distribution and cloud ice water path, has been investigated. The single scattering parameters of the cloud particles were determined using Mie theory for distributions of spheres and the T-Matrix method for spheroids. Cloudy-sky radiances, fluxes and

Jaqueline E. Russell; Richard J. Bantges; Catherine Naud; Joanna D. Haigh

1998-01-01

227

Plasma-induced oxide contamination in a 0.35-um CMOS process  

NASA Astrophysics Data System (ADS)

Plasma contamination in a 0.35 micrometer triple-level metal CMOS process was investigated in response to anomalous dc parametric test data. Electrical PMOS transistor performance and both physical and electrical gate oxide thickness were significantly degraded upon exposure of a sacrificial oxide to a plasma ash following a masked, P-channel threshold adjust ion implant. The contamination was isolated to a specific asher, found to be radial in nature across a wafer, and consistently worse in one of the two chambers used during the ash process. The contamination dramatically reduced the wet etch rate of the sacrificial oxide, leading to incomplete removal prior to gate oxide growth. Increasing the wet strip time of the sacrificial oxide improved the ability to remove this contaminated film, but was limited by minimal field oxide thickness requirements to avoid field inversion. Transferring the ash process to an alternative, low-damage, down-stream asher eliminated the plasma contamination.

Karnett, Marty P.; Zhou, Jingrong; Ghosh, Sumanta; Echtle, Danny; Fritz, L.; Manley, M.; Scott, G.

1996-09-01

228

Board level reliability study for CSP with 400 um ball pitch  

Microsoft Academic Search

For handheld products, drop impact is a great concern to simulate mishandling during usage. The primary driving force of the electrical failure is rapidly winding of circuit board due to high-accelerated strain. Therefore, the board level drop test is created to go through the performance of dropping the handheld electronic product. At the present days, Sn1Ag0.5Cu solder ball is adopted

Yeng-Ping Wang; Don-Son Jiang; Yu-Po Wang; C. S. Hsiao

2007-01-01

229

Optical coatings of the 3.8-um reflecting and visible transmitting  

NASA Astrophysics Data System (ADS)

The optical performance of beam splitters developed for deuterium fluoride (DF) laser applications as shared- aperture components is presented. This component simultaneously has provided high reflectance in 3.8 micrometers DF laser output band and high transmittance in the visible wavelength region. The coating consists of a number of periods of multilayer stack which is reflecting in the infrared and transmitting at visible wavelengths. The period is formed of alternate high index ZnS and low index YbF3 materials layers which are transparent in the infrared and visible wavelengths. The 99.2% reflectance at 3.8 micrometers DF laser output band and 75.0% transmittance at 0.4 approximately 0.9 micrometers visible band have been obtained. The laser damaged threshold is more than 20 kw/cm2 at DF CW laser illumination.

Xiong, Shengming; Zhang, Yundong

1998-08-01

230

Eletrodinamica quantica sem massa nua do eletron: um estudo variacional. (Massless quantum electrodynamics: a variational study).  

National Technical Information Service (NTIS)

The variational method was used to study the probable existence of a compound vacuum in quantum electrodynamics. An Ansatz containing a condensate of electron-positron pairs was investigated and an optimization equation for the condensate wave function fo...

P. C. Piquini

1990-01-01

231

"Um, They Weren't Thinking about Their Thinking": Children's Talk about Issues of Oppression  

ERIC Educational Resources Information Center

This article presents first and second grade children's talk about issues of language diversity and culture. Children focus on the issue of oppression and initially examine oppressors in their talk within literature circles across a year in a Sheltered English Immersion classroom. Drawing on a critical literacy framework and anti-bias perspective,…

Fain, Jeanne Gilliam

2008-01-01

232

COCOMO II - Um modelo para estimativa de custos de Gerência de Projetos  

Microsoft Academic Search

This paper shows as estimates establishment constitutes one of the main activities of software project planning. It also considers a methodology for the elaboration of estimates using the model Constructive Cost Model II (CoCoMo II) and it is presented the result of the application of this methodology considering comparison of cost esteem for the company, the cost really reached and

Pablo Ariel; Caixa Postal

2005-01-01

233

Um Estudo sobre Gerência de Configuração de Software aplicada ao Desenvolvimento Baseado em Componentes  

Microsoft Academic Search

This study aims to analyze the Software Configurati on Management (SCM) approach for conventional development and identify points that need to be tai lored to support Component Based Development (CBD). We believe that adapting SCM process to support CBD by applying variants for producer and consumer teams is the best way to take advantage of the benefits of SCM a

Ribeiro Dantas; Hamilton Oliveira; Leonardo Gresta; Paulino Murta; Cláudia Maria; Lima Werner

234

1.3\\/1.55-um duplex-diplex optical transmission: the Brazilian technology  

Microsoft Academic Search

Results are presented from the first installed Brazilian link in which four independent optical channels operating at 1.30 and 1.52 micron have been combined using duplex-diplex wavelength-division multiplex (WDM) configuration on a standard single-mode fiber link. The optical emitters and detectors were linked to a 24 km installed single-mode route through two MUX devices. This dual-wavelength and bidirectional scheme of

Sergio Celaschi; Joao B. Rosolem; J. T. Jesus; Jorge S. Pereira

1993-01-01

235

Zum Auf und Ab des Meeresspiegels in Skandinavien: Langer Streit um Eustasie oder Isostasie  

NASA Astrophysics Data System (ADS)

The phenomenon of the rise of the Scandinavian shield during the Holocene and the concomitant fall in level of the Baltic Sea has been investigated for centuries. Already in medieval times, there were reports about the coastlines of the Gulf of Bothnia that are full of relevant observations. During the eighteenth century, scientists such as Celsius and Linnaeus collected observations such as these. The result was that the search for the possible explanations of this rise-and-fall phenomenon intensified. The generally favoured explanation was that there was an active sinking of sea level in the Baltic rather than an active rising of the land surface in Fennoscandia. This was because water was seen as mobile, in contrast to a „terra firma". The relevant discussion was often emotional, and here, we try to illustrate it using material from the Geologenarchiv Freiburg (von Hoff, von Buch and Goethe). No more than a few decades later, it became obvious by the theory of Ice Age that both the sea level and the land could be mobile (eustatic sea level changes—glacial isostasy). Additionally, of course, plate tectonics had some influence: Norway is situated at the western end of the Eurasian plate and is part of a passive continental margin. There are still open research problems, many of which can be addressed using modern methods of satellite-based geophysics and geodesy. Some other aspects as the permanent uplift trend of Scandinavia since the Cambrium or the rhythmic to and fro of magma in the upper mantle during the Pleistocene are mentioned.

Seibold, Eugen; Seibold, Ilse

2012-03-01

236

Pulpal safety of a 9.6-um TEA CO2 laser used for caries prevention  

NASA Astrophysics Data System (ADS)

Lasers are used for several procedures involving hard and soft tissues of the oral cavity. Included in those procedures is the use of the CO2 laser to alter the surface structure of tooth enamel to render it more resistant to caries. A new 9.6micrometers wavelength TEA CO2 laser (Argu Photonics, Jpiter, FL) has been investigated as a device that can be used for this procedure without harming the dental pulp. Erupted, caries and restoration free third molars (n=24) were used in the experiment. Teeth were irradiated at an incident fluence of 1.5J/cm2 and a repetition rate of 10Hz and a spot size 1mm in diameter. At the low and high settings, 200 to 400 pulses were delivered at 12mJ per pulse for a total energy of 2.4 or 4.8J delivered for 20 or 40 seconds respectively. Other teeth were subjected to a sham dental procedure (positive control) or no procedure (negative control). Prior to testing, radiographs were taken of all teeth, and they were tested pulpally using heat, cold and electricity to determine vitality. The teeth were removed either immediately or at one week or one month after testing. They were bioprepared and examined histologically for signs of inflammation. Only one tooth developed symptoms of sensitivity to cold for 10 days following exposure to the high power level. The sensitivity was of fleeting duration and was judged to be reversible pulpitis. All teeth tested responded normally at pretesting and pre-extraction time periods. Histological examination disclosed no indication of an inflammatory response in the pulp tissue. All sections appeared normal with no changes seen in the normal pulpal morphology. We conclude that the 9.6 micrometers wavelength laser causes no pulpal damage at the energy levels used and can be used safely for caries prevention treatments.

Goodis, Harold E.; Fried, Daniel; Featherstone, John D.

2002-06-01

237

65 FR 62581 - List of Approved Spent Fuel Storage Casks: NAC-UMS Addition  

Federal Register 2010, 2011, 2012, 2013

...canister walls and away from the canister through natural convection by air circulation over the canister's outer surface...the canister (by presumably providing some form of forced convection) prior to being required to remove it from the...

2000-10-19

238

Atmospheric Attenuation of Laser Radiation from 0.76 to 31.25/um.  

National Technical Information Service (NTIS)

High resolution atmospheric transmittance curves are presented for the spectral region 320 to 13,200/cm (0.7576 to 31.25 micrometers). These spectra are useful as a guide for selecting laser wavelengths for atmospheric propagation studies in this spectral...

J. E. A. Selby R. A. McClatchey

1974-01-01

239

Sobre a quantizacao de um sistema classicamente caotico. (Quantization of classically chaotic system).  

National Technical Information Service (NTIS)

Some propeties of a quantization in terms of observables of a classically chaotic system, which exhibits a strange are studied. It is shown in particular that convenient expected values of some observables have the correct classical limit and that in thes...

N. F. Godoy

1988-01-01

240

High-speed serial communication with error correction using 0.25 um CMOS technology  

Microsoft Academic Search

In this paper we propose a novel design for an autonomous high-speed serial off and on-chip communication system which incorporates impedance tuning, error correction with a packet transfer and a parallel asynchronous interface. The constructed transmitter-receiver pair has throughput of 5 Gbit\\/s. With error correction and packet transfer overhead accounted for this construct has bandwidth of 500

Teemu Suutari; Jouni Isoaho; Hannu Tenhunen

2001-01-01

241

Efficient first-overtone CO laser (I=2.5-4.2 um)  

Microsoft Academic Search

An overview of theoretical and experimental results on first- overtone (FO) CO laser is presented. A special attention is paid to the quite new results jointly obtained at the Lebedev Physics Institute (Russia), TRINITI (Russia) and Air Force Research Lab (USA). Efficient multiwavelength pulsed FO CO lasing with output efficiency up to 11% and specific output energy up to 50

Andrei A. Ionin

2000-01-01

242

NCI Funded Research Portfolio - 1UM1CA167552-01 Detail  

Cancer.gov

Skip to content Your source for National Cancer Institute funded research grants, contract awards, and intramural research projects. More Home Advanced Search Funding Statistics About NFRP Contact Us Related Links Help Viewing Project « Back to results

243

U.S. Court of Claims Deposition of Kish um us tubbee. Teaching with Documents.  

ERIC Educational Resources Information Center

Discusses the expulsion of the Choctaw Indians from their lands in the U.S. southeast as a result of the Indian Removal Act of 1830. Provides a lesson plan using a primary source document along with accompanying discussion questions. Includes a three-page letter that is the deposition of a Choctaw Indian protesting removal. (CFR)

Blondo, Richard A.; And Others

1994-01-01

244

Peculiarities of coagulation action of IR lasers (1-3 um) radiation on cornea  

NASA Astrophysics Data System (ADS)

Antiviral, antibacterial, antitumoral effects of laser coagulation are now of great importance in clinical ophthalmology for different corneal diseases treatment. One can note, that nowadays solid-state free-mode pulsed near-and-mid-infrared lasers with the 1.3 - 3.0 micrometers wavelengths may become widespreadly accepted in this field of ophthalmosurgery. The corneal tissue absorption coefficients for these wavelengths are lying from some parts to several thousand cm-1. Thus, by proper selection of laser wavelength, possibility is appeared to coagulate precisely the seat of pathological alterations without damaging of more deeper, non changed corneal tissue. In our work the comparative experimental study results of rabbit cornea coagulation after exposure with using of different IR lasers (with 1.32; 1.54; 1.96; 2.09 and 2.84 micrometers wavelengths) are presented. Pulse duration was about 10-3 s. The subthreshold, threshold and superthreshold energy levels were studied. Threshold energies were registered if slightly noticed coagulative changes appeared in exposed volume of corneal tissue. The cornea response resulting from laser radiation exposure was evaluated by clinical examination, slit lamp biomicroscopy, light microscopy, fluorescent staining and biochemistry. For all wavelengths initial damage was found within the cornea layers. Superthreshold injury revealed the same picture except that for 1.32 micrometers the threefold increase of the threshold energy caused additionally iris injury. The damages of the cornea were marked near the surface, stretched to more deeper layers, and damage zones were extended from the epithelium for 2.84 micrometers wavelength to whole cornea thickness for 1.32 and 1.54 micrometers wavelengths and have intermediate position for 1.96 and 2.09 micrometers wavelengths, depending on the corneal absorption coefficient. Quantitative results of threshold energy levels were calculated by probit-analysis. The radiant exposure (HD50), that cause the threshold coagulation changes in cornea with 50% probability was determined for the beam diameter (irradiance diameter) of 2 mm and for 1.32; 1.54; 1.96; 2.09 and 2.84 micrometers wavelengths. Values determined were (2.4 +/- 0.2) X 10; 7.2 +/- 0.6; 2.9 +/- 0.5; 3.7 +/- 0.2; (1.9 +/- 0.4) X 10-1 J/cm2. These values are well-correlated to corneal absorption coefficients. The absorption coefficient the higher, the value HD50 the lower and the `danger' for ocular structures damage also the lower. This fact is needed to be taken into account, because of normative documents did not reflect it in 1.3 - 3.0 micrometers wavelength range. The obtained results may be used for development of new clinical laser applications and refinement of the laser safety standards.

Berezin, Yuri D.; Boiko, Ernest V.; Volkov, Venjamin V.; Danilichev, Vladimir F.; Ganin, Dmitry V.; Gatzu, Andrey F.; Smirnov, Nicolay N.; Lazo, Victor V.; Tkachuk, Alexandra M.

1996-04-01

245

OWL: an eyesafe 1.5-um laser radar system for military applications  

Microsoft Academic Search

The paper reports on current advances in the development of the Dornier Obstacle Warning System (OWS) for helicopters, with particular emphasis on the Obstacle Warning Ladar (OWL). Here both segments, development and application of the 1.5 micrometer imaging laser radar (LADAR) will be represented. It will be shown how advances in the eyesafe LADAR technology resulted in Obstacle Warning Ladar

Max Eibert; Stefan Scherbarth

1998-01-01

246

Wide-field variable NA lens analysis for high-volume 0.5-um manufacturing  

NASA Astrophysics Data System (ADS)

Several techniques were used to evaluate and compare various lenses: optical, SEM, and electrical. In this paper, the emphasis is on `usable' critical dimensions and the effects of the lens on CD control. Lens results were examined at multiple numerical apertures (NAs) and partial coherence settings (PC) using a CD reticle with electrical CD structures over seventeen sites per field. The results were analyzed by electrical methods and a scanning electron microscope (SEM) with CD capability. The influence of external factors was minimized through the use of the same resist/developer batch at all testing locations. We selected electrical and SEM measurement methods for 0.40, 0.45, 0.50 micron structures and compared depth-of-focus, exposure latitude, CD linearity, and isolated vs. dense line/space pairs. Preliminary results show the benefits of electrical testing for increased confidence over the full lens field because of increased sample size. The optical method provided a quick and centered capability and matched electrical results closely. This testing methodology allowed AMD to evaluate lens performance of multiple systems and compare performance equally.

Ackmann, Paul W.; Brown, Stuart E.; Edwards, Richard

1994-05-01

247

Thermal response of hard dental tissues to 9- through 11- um CO2-laser irradiation  

NASA Astrophysics Data System (ADS)

The morphology and the chemistry of dental enamel and dentin can be modified by irradiation with a CO2 laser to increase the acid resistance of the intrinsic mineral. The changes induced in hard dental tissues after laser irradiation are predominantly determined by the photothermally induced temperature rise in the tissue. Therefore the temperature rise in the irradiated enamel and dentin must be determined under controlled laser conditions. Surface and subsurface temperatures were monitored after multiple-pulse CO2-laser irradiation at (lambda) equals 9.3, 9.6, 10.3, and 10.6 micrometers with 1- and 20-J/cm2 pulses of 50- to 500-microsecond(s) duration using radiometry and microthermocouples. Surface temperatures were significantly higher after 9.3- and 9.6-micrometers irradiation than for the more commonly utilized 10.6-micrometers CO2-laser wavelength. Permanent changes in the temperature response of enamel and dentin were observed at fluences greater than 2 J/cm2 and 100-microsecond(s) duration for dentin and 5 J/cm2 for enamel. CO2-laser irradiation changes the thermal and the optical properties of these tissues, substantially changing the energy deposition for subsequent laser pulses. These changes affect both the amount of energy absorbed and the depth of absorption. The more efficient absorption at (lambda) equals 9.3 and 9.6 micrometers may be advantageous for both caries-preventive treatments and ablation of exposed hard dental tissues while minimizing heat deposition in the tooth.

Fried, Daniel; Seka, Wolf D.; Glena, Richard E.; Featherstone, John D.

1996-07-01

248

Mask defect printability at 0.18-um design rules for 193-nm lithography  

NASA Astrophysics Data System (ADS)

In this paper, the printability of mask defects at 0.18 micrometers design rule is studied via 193 nm top surface imaging (TSI) resist process. The mask defect printability is determined by taking into account the wafer process critical dimension (CD) variability. In the experiment, an 193 nm microstepper with 0.6 NA imaging lens was used to expose the programmed defect mask. The resist CD response to the mask defect area is measured under the different process conditions, i.e., different exposure dose or focus. It is found that similar to a single layer 248 nm DUV resist case that has been studied before, the TSI resist CD responds to the mask defect area linearly for the small mask defects. From such a set of CD-defect response lines, the allowable mask defect requirement is assessed via the statistical explanation of the printable mask defect size which is tied to the wafer process specifications and the actual wafer process CD controllability. Its printability is further verified by the process window measurements. Our results showed that for 193 nm exposure and TSI resist process, a mask defect as small as 0.13 micrometers (4X) is printable at 0.18 micrometers design rule. This printable mask defect size is approximately independent of mask bias in a linear CD region, i.e., a region in which the resist CD responds to the mask CD linearly. Although the above experimental results are obtained based on a TSI process, many characteristics of mask defect behavior can be generalized to the other resist processes. Based on the statistical defect printability analysis method that we have developed, the printable mask defect size can always be re-defined without additional data collection when the process control or the process specification changes.

Yan, Pei-Yang; Tran, An; Schmidt, Michael R.

1997-07-01

249

Mask CD control requirement at 0.18-um design rules for 193-nm lithography  

NASA Astrophysics Data System (ADS)

In this paper, the mask critical dimension (CD) control budget for the 0.18 micrometers generation design rules are assessed via experimental based data. The lithography tool used for wafer exposure is 193 nm microstepper with NA of 0.6. The resist process used is the top surface imaging (TSI) resist process. In the study, the process CD variation due to mask CD error, mask CD error combined with process variation such as focus and exposure, mask CD error combined with low kl imaging limitation, and mask CD error combined with the characteristics of a given resist process, such as feature dependent silylation, are investigated. It is found that for the lines with a relative larger pitch (e.g., pitch is approximately 2X the line width), the resist CD responds to the mask CD linearly down to a 0.16 micrometers feature size. However, unlike the most single layer resist processes, the slope of the line, i.e., (Delta) CD(wafer)/(Delta) CD(mask), in the above mentioned TSI process is not equal to 1. Their values are between 1.2 - 1.7, depending upon the pitch. This means that for a given mask CD error, the corresponding wafer CD error will be 1.2 - 1.7 times larger. In other words, the mask CD control budget will not scale the same as that of wafer CD control budget when the design rule scales. In fact, the mask CD control budget should be at least 1.2 - 1.7 times tighter than that of the wafer CD budget scaling. In the case of contacts, the resist CD linearity only extends to the 0.375 micrometers feature size with a slope approximately equals to 1. For the contacts smaller than 0.375 micrometers , the slopes are greater than 1 depending upon the exact mask contact sizes. For the contacts smaller than 0.25 micrometers , the slopes are between 2 - 3, depending upon the pitch. In addition, it is found that the defocus increases the slope value significantly for the small contacts sizes. The slopes for the case of lines, however, are found much less sensitive to the defocus conditions (defocus equals +/- 0.2 micrometers approximately +/- 0.3 micrometers ). Our assessment showed that mask CD control budget (4X) for 0.18 micrometers design rules are necessary to be in a range of +/- 8 nm approximately +/- 12 nm (4X), assuming that +/- 25% of total wafer CD budget which is +/- 10% of the target CD is given to the mask.

Yan, Pei-Yang; Langston, Joseph C.

1997-07-01

250

Zur Frage der unspezifischen Sarkomentstehung um Al 2 O 3 -keramische Implantate  

Microsoft Academic Search

This investigation presents experimental results on possible non-specific foreign body sarcoma induction by Al2O3-ceramic implants. Solid and porous discs, subcutaneously implanted in rats produce a sarcoma rate of 17.4 resp. 17.8 p.c. while roughly perforated discs initiate sarcomas at a rate of 25.4 p.c. These values were found to be lower than comparative values in the literature produced with different

Peter Griss; Eberhard Werner; Rainer Buchinger; Carl-Michael Büsing; Günther Heimke

1977-01-01

251

Geni e o Zepelim X Bola de Sebo : a intertextualidade vista como um procedimento de originalidade  

Microsoft Academic Search

The aim of the comparative analysis between the intertextual variant Geni e o Zepelim , written by Chico Buarque de Holanda, and the basis text Boule de Suif , written by Guy de Maupassant, is to prove that, despite recovering another's discourse, intertextuality adds to the originality of the creation undertaken by the subject's enunciation variant. Such statement is justified

Fernanda Isabel Bitazi

252

Relação entre mercado de terras, crescimento econômico e insegurança fundiária explicada por um modelo a \\  

Microsoft Academic Search

Relationship between the land market, economic growth and land insecurity explained by an overlapping model. In this paper, we analyze the relationship bet- ween the land market failures and the economic growth in Brazil, starting from an overlapping model including two sectors: agricultural and industrial. The land is both a specific factor for agriculture and an asset that can be

Claudio Araujo; Catherine Araujo Bonjean; Jean-Louis Combes; Pascale Combes Motel

2006-01-01

253

Laser megajoule 1.06-um mirror production with very high laser damage threshold  

NASA Astrophysics Data System (ADS)

As part of the LMJ (Laser Megajoule) program, CEA is building the LIL laser with full size optics and LMJ requirements. SAGEM has been selected as the supplier of large optical components and coatings with very high laser- induced damage threshold. Including spare parts, about 100 mirrors 610*430 mm2 with LIDT-3 ns $GTR 25 J/cm2 have to be produced. Using a 5 m3 vacuum chamber and the 100 J/cm2 mirror coating process developed at CEA-LETI, with Hafnium and SiO2 materials, we are now typically in a serial production phase. To date, about thirty mirrors have been delivered. This paper focuses on the acceptance tests performed after coating, at SAGEM then CEA: LIDT measurement and Raster-Scan on samples; reflectance mapping on CEA automatic photometer; reflected wavefront deformation with 800 mm/1(omega) CEA interferometer.

Pinot, B.; Leplan, Herve; Houbre, Francois; Lavastre, Eric; Poncetta, Jean-Christophe; Chabassier, Genevieve

2002-03-01

254

GNU Mages - Um Ambiente para Simulação de Múltiplos Agentes Autônomos, Cooperativos e Competitivos  

Microsoft Academic Search

We describe the implementation of a cooperative and competitive autonomous multi agents s imulation environment. The main go al of t his application is to p rovide statistical comparisons between d ifferent Artificial Intelligence algorithms applied in games. GNU Mages is free software and we hope to help all community with creation of this new open tool very useful to

João Ricardo Bittencourt; Fernando Osório

255

Long-wavelength optical coherence tomography at 1.7 um for enhanced imaging depth  

PubMed Central

Multiple scattering in a sample presents a significant limitation to achieve meaningful structural information at deeper penetration depths in optical coherence tomography (OCT). Previous studies suggest that the spectral region around 1.7 µm may exhibit reduced scattering coefficients in biological tissues compared to the widely used wavelengths around 1.3 µm. To investigate this long-wavelength region, we developed a wavelength-swept laser at 1.7 µm wavelength and conducted OCT or optical frequency domain imaging (OFDI) for the first time in this spectral range. The constructed laser is capable of providing a wide tuning range from 1.59 to 1.75 µm over 160 nm. When the laser was operated with a reduced tuning range over 95 nm at a repetition rate of 10.9 kHz and an average output power of 12.3 mW, the OFDI imaging system exhibited a sensitivity of about 100 dB and axial and lateral resolution of 24 µm and 14 µm, respectively. We imaged several phantom and biological samples using 1.3 µm and 1.7 µm OFDI systems and found that the depth-dependent signal decay rate is substantially lower at 1.7 µm wavelength in most, if not all samples. Our results suggest that this imaging window may offer an advantage over shorter wavelengths by increasing the penetration depths as well as enhancing image contrast at deeper penetration depths where otherwise multiple scattered photons dominate over ballistic photons.

Sharma, Utkarsh; Chang, Ernest W.; Yun, Seok H.

2009-01-01

256

TOPIC IDENTIFICATION IN DYNAMICAL TEXT BY EXTRACTING MINIM UM COMPLEXITY TIME COMPONENTS  

Microsoft Academic Search

The problem of analysing dynamically evolving textual data has recently arisen. An example of such data is the discussion ap- pearing in Internet chat lines. In this paper a recently intr oduced source separation method, termed as complexity pursuit, is applied to the problem. The method is a generalisation of projection pur- suit to time series and it is able

Ella Bingham

257

Zum Auf und Ab des Meeresspiegels in Skandinavien: Langer Streit um Eustasie oder Isostasie  

Microsoft Academic Search

The phenomenon of the rise of the Scandinavian shield during the Holocene and the concomitant fall in level of the Baltic\\u000a Sea has been investigated for centuries. Already in medieval times, there were reports about the coastlines of the Gulf of\\u000a Bothnia that are full of relevant observations. During the eighteenth century, scientists such as Celsius and Linnaeus collected\\u000a observations

Eugen SeiboldIlse Seibold; Ilse Seibold

2011-01-01

258

Experimento Virtual de Controle: Uso de Técnicas de Realidade Virtual para a Construção de um Sistema \\  

Microsoft Academic Search

The main purpose of this paper is the development of a virtual experiment to be used as a teaching tool for control disciplines. A linearized mathematical model of the system in the state-space form is used to project a controller using pole location. The three-dimensional ambient which represents the Ball-Beam dynamic system was built using the API Java 3D. The

Éder Torres Patrício; Max Rothe-Neves; Orlando Fonseca Silva

259

Os beija-flores e seus recursos florais em um fragmento florestal de Viçosa, sudeste brasileiro  

Microsoft Academic Search

Hummingbirds and their floral resources in a forest fragment in Viçosa, southeastern Brazil. Between August 1998 and August 1999, hummingbirds and plant species used by an them as nectar sources were recorded in the Mata do Paraíso forest reserve. This area is a regeneration of Atlantic Forest with an area of 194.36 ha. It is located in the municipality of

Carlos R. M. Abreu; Milene F. Vieira

2004-01-01

260

Optical design of the 1-5-um infrared camera of the IAC  

NASA Astrophysics Data System (ADS)

An infrared liquid nitrogen (LN2) cooled focal reducer camera has been designed to be used at the 1.5 m (f/13.8) Carlos Sanchez IR Telescope (CST) at the Observatorio del Teide. The image quality is better than 30 micrometers (typical pixel size of the detector) with an image scale of 0.5 arcsec/pixel. The final design is a very compact system which consists of a centered reflective system with a CaF(subscript 2) lens which will be used as window of the dewar. The system is free of chromatic aberration, reduces the amount of coma presents in the telescope and allows us to get a homogeneous image quality over the detector. Vignetting effects on the transmission are studied and found below the 20%. The use of aluminum diamond turned optics lets us obtain the tight tolerances needed to get the maximum optical performance with a system which is practically insensitive to temperature changes. Spot diagrams at different wavelength from 1 to 5 micrometers using a real simulation of the complete system (CST + camera) are presented. The baffling of the system is also analyzed.14

Manescau, Antonio; Fuentes, F. Javier; Sanchez, Vicente

1993-10-01

261

Optical proximity correction for 0.15-um-rule memory devices  

NASA Astrophysics Data System (ADS)

Optical proximity correction (OPC) is applied to the cell patterns of 0.15-micrometer-rule memory devices. Two kinds of memory cell patterns are studied. The first is a wire pattern which has small gaps between two wires. The small gaps can be clearly resolved by using OPC such as jogs or resizing. The second pattern is a storage node pattern which has a rectangular shape. The area of the storage node is enlarged by using OPC such as resizing, hammer heads or serifs. These OPC masks are successfully fabricated by using dry etching process.

Iwasaki, Haruo; Tanabe, Hiroyoshi; Inoue, Takashi; Tanaka, Yoshiyuki

1998-12-01

262

High-reliability nonhermetic 1.3-um InP-based uncooled lasers  

Microsoft Academic Search

We report the first uncooled non-hermetic 1.3 micrometer InP-based communication lasers that have reliability comparable to their hermetically packaged counterparts for possible applications in fiber in the loop and cable TV. The development of reliable non-hermetic semiconductor lasers would not only lead to the elimination of the costs specifically associated with hermetic packaging but also lead the way for possible

Naresh Chand; J. W. Osenbach; T. L. Evanosky; Robert B. Comizzoli; Won-Tien Tsang

1996-01-01

263

Optical detector selection for 1.5-um KTP OPO atmospheric lidar  

Microsoft Academic Search

A 1.5 micron wavelength KTP OPO Lidar system has been developed and used to study the sensitivity and the system signal-to-noise ratio for hard target and atmospheric aerosol lidar returns. Optimization of the receiver system was studied that included the use of different sizes, types of detectors, and the effect of laser beam quality factor, M2, on the telescope overlap

Priyavadan Mamidipudi; Dennis K. Killinger

1999-01-01

264

Optical detector selection for 1.5-um KTP OPO atmospheric lidar  

NASA Astrophysics Data System (ADS)

A 1.5 micron wavelength KTP OPO Lidar system has been developed and used to study the sensitivity and the system signal-to-noise ratio for hard target and atmospheric aerosol lidar returns. Optimization of the receiver system was studied that included the use of different sizes, types of detectors, and the effect of laser beam quality factor, M2, on the telescope overlap function. Detectors that were studied included several different sizes of InGaAs APDs, direct photodetectors, a transferred-electron intensified photodiode (TE-IPD), and a PMT. The influence of the diffraction or beam quality factor (M2) of the OPO laser was studied and found to have a significant influence on the overlap of the transmit and receiver field of view. This overlap function is also influenced by the size of the lidar detector since a large M2 value can overfill the detector/telescope field of view so that small (high speed) detectors may be subject to a large reduction in the lidar signal. The size of the photodiodes and APDs used in the initial OPO lidar experiments were of the order of 0.1 mm to 2 mm, while the TE-IPD and the PMT are larger in acceptance area. Some initial experimental measurements with the photodetectors and APD, and projected theoretical comparisons with the TE-IPD and PMT detectors have been made.

Mamidipudi, Priyavadan; Killinger, Dennis K.

1999-05-01

265

AIR FILTER PARTICLE-SIZE EFFICIENCY TESTING FOR DIAMETERS GREATER THAN 1UM  

EPA Science Inventory

The paper discusses tests of air filter particle-size efficiency for diameters greater than 1 micrometer. valuation of air cleaner efficiencies in this size range can be quite demanding, depending on the required accuracy. uch particles have sufficient mass to require considerati...

266

SNIFFER: Um Ambiente Computacional para Gerenciamento de Experimentos de Aprendizado de M´ aquina Supervisionado  

Microsoft Academic Search

Machine Learning -ML - is an inherently empirical research area since it is not possible to determine mathematically whether aML algorithm will perform bet- ter than others. In other words, experimental studies should be carried out in order to understand and explain the differences between learning algorithms. However, experi- mental evaluation envolves executing a variety of experiments several times, which

Gustavo E. A. P. A. Batista; Maria Carolina Monard

267

The optimization of zero-spaced microlenses for 2.2um pixel CMOS image sensor  

Microsoft Academic Search

In CMOS image sensor, microlens arrays are generally used as light propagation carrier onto photo diode to increase collection efficiency and reduce optical cross-talk. Today, the scaling trend of CMOS technology drives reduction of the pixel size for higher integration density and resolution improvement. Microlenses are typically formed by photo resist patterning and thermal reflowing, and the space between photo

Hyun hee Nam; Jeong Lyeol Park; Jea Sung Choi; Jeong Gun Lee

2007-01-01

268

Geochemical reconnaissance survey and environmental assessment for stream sediments of Wadi Um Gier, Southeastern Desert, Egypt  

Microsoft Academic Search

The purposes of this study were to assess the influence of old mining activities on the geochemistry and quality of sediments\\u000a and to identify the sites of economic elements. Thirty sites of stream sediment were sampled in the study area covered by\\u000a granitic, metarhyodacitic and meta-andesitic rocks and related tuffs-hosted abandoned Au mine. The suite of chemical elements,\\u000a Ag, Bi,

Mohamed Abdallah Gad Darwish; Gad Darwish

2011-01-01

269

0.18-um optical lithography performances using an alternating DUV phase-shift mask  

NASA Astrophysics Data System (ADS)

The phase shift mask (PSM) is a key emerging technology thought to be extending 248 nm lithography. In this paper, we describe the lithographic performances of Shipley UV5 photoresist on SiOxNy Bottom Anti Reflective coating (BARC), using alternating PSM and ASM/90 Deep-UV stepper. Results on 0.18 micrometer design rules are presented: lithographic performances, comparison between PSM and binary mask, sub 0.18 micrometer performances ({1}) and the ultimate resolution of this technology are reported. To conclude we demonstrated the 0.18 micrometer lithography feasibility with alternating mask and KrF stepper, and showed that all the necessary tools are today available to achieve such goals.

Trouiller, Yorick; Buffet, N.; Mourier, Thierry; Schiavone, Patrick; Quere, Y.

1998-06-01

270

Analise e construcao de um piranometro fotovoltaico. (Construction and analysis of a photovoltaic pyranometer).  

National Technical Information Service (NTIS)

The aim of this work is to analyze the behavior of a silicon cell as a sensor in a pyranometer and and to construct a prototype of this instrument. First it was analyzed the possibility of using a silicon cell as a sensor, emphasizing the influence of its...

I. Zanesco

1991-01-01

271

Regente: Um Arcabouço para Gerenciamento Eficiente de Orquestrações de Serviços Web  

Microsoft Academic Search

Web services orchestration can be executed using either centralized or disperse (decentralized) models. Several studies suggest that the disperse model performs better in terms of throughput, scalability and response time. However, such assumption does not always hold since the efficiency of each model depends on variants like the orchestration specification and the organization of nodes that provide the Web services

Cássio J. S. Freire; Paulo F. Pires; Flávia C. Delicato; Maria Luiza; M. Campos; Luci Pirmez; Marcel V. M. Oliveira

2007-01-01

272

Near-IR stellar spectra from 1.428 to 2.5 um (Lancon+ 1996)  

NASA Astrophysics Data System (ADS)

This library is an EXTENDED VERSION of the library published by A.Lancon and B.Rocca-Volmerange in 1992. The catalog contains near-IR spectra of 84 stars, obtained with the Fourier Transform Spectrograph at the Canada-France-Hawaii Telescope on Mauna Kea, Hawaii. The spectra cover the H and K atmospheric windows, i.e. wavelengths from 1.43 to 2.5 microns, with a typical resolving power of 500. The spectra have all been reduced again in 1996. The general procedure was as described in the original article, except that the intrinsic energy distributions of the stars used as references were assumed to be well represented by the models of Kurucz, 1993. Making extensive use of the Simbad data base, we have searched the literature on each of these stars, looking for effective temperature and extinction determinations. The new reduction improves the reliability of the continua, and reduces possible systematic differences between observing runs. The files contain the reduced spectra in FITS format, with fluxes in arbitrary units of energy per unit frequency (normalised to approximately 1 in the K band) and frequencies in cm-1, the natural units of Fourier Transform spectroscopy. (4 data files).

Lancon, A.; Rocca-Volmerange, B.

1997-02-01

273

Low-pressure aluminum planarization for sub-0.5-um contact and via holes  

Microsoft Academic Search

A novel Al-0.5%Cu planarization technology for interconnects is presented using a low pressure Al physical vapor deposition process (or MaxFillTM), capable of filling high aspect ratio (A\\/R >= 3) via holes at wafer temperatures of less than or equal to 400 degree(s)C. Excellent Al film reflectivity and surface smoothness are achieved due to hardware modifications to the sputter tool and

Maxmilian A. Biberger; D. Conci; J. Lyons; M. Rumer; L. Tam; G. Tkach; V. Hoffman; E. P. Martin; Sailesh M. Merchant

1997-01-01

274

Competência social e empatia: um estudo sobre resiliência com crianças em situação de pobreza  

Microsoft Academic Search

Social competence and empathy: Study about resilience with children in poverty Resumo O objetivo desse estudo foi avaliar a competência social e a empatia em crianças escolares que vivem em situação de po- breza. Participaram da pesquisa 100 crianças, de ambos os sexos, com idades entre seis e nove anos. Os instrumentos utilizados foram o Teste das Histórias Incompletas (THI)

Alessandra Marques Cecconello; Sílvia Helena Koller

2000-01-01

275

Crianças em situação de rua de Porto Alegre: um estudo descritivo  

Microsoft Academic Search

The present paper presents a description of a sample of street children from a central area of Porto Alegre, Brazil. Twenty children, twelve boys and eight girls, aged six to 12 years were interviewed. The interview was structured to investigate the relationships between the children and their family, work and school activities, and the way they spent their time. The

Aline Santos e Silva; Caroline Tozzi Reppold; Clarisse Longo dos Santos; Luciano Telles Prade; Milena Rosa Silva; Sílvia Helena Koller

1998-01-01

276

O DISCURSO EXPOSITIVO ESCRITO NO ENSINO FUNDAMENTAL. UM ENFOQUE COGNITIVISTA E SEUS DESDOBRAMENTOS DIDÁTICOS  

Microsoft Academic Search

RESUMO: Propomos uma análise do discurso didático expositivo escrito, em textos do ensino fundamental, focalizando dois aspectos principais. Em primeiro lugar, consideramos o funcionamento cognitivo desse tipo de discurso, com base nas perspectivas de Bruner (1998; 2001) e Bronckart (1999). Em segundo lugar, examinamos algumas de suas principais estruturas semânticas, a partir da abordagem da lingüística cognitiva (Langacker. 1987; 1991;

Luís Passeggi

277

Um estudo sobre a permanência e a evasão na Educação a Distância 1  

Microsoft Academic Search

The article describes a research carried out in distance education. In this experience it was our aim to investigate the evasion in this education system, distance education. The interactions were analysed in the light of some categories in order to identify the dialoguesconversations in the perspective of Paulo Freires and Jean Piagets theories. It showed the need of dialogue conversation

Rute Vera; Maria Favero

278

DESENVOLVIMENTO RURAL, MULHERES E TERRA - UM OLHAR SOBRE TIMOR-LESTE  

Microsoft Academic Search

O caminho percorrido para que as questões do género e do desenvolvimento e em especial a sua interligação sejam assuntos importantes e alvo de atenção tanto académica como política, foi longo. Várias áreas do conhecimento, como a sociologia, a antropologia e a economia, contribuem para a construção do conhecimento neste domínio, a par de outras mais recentes como os estudos

Vanda Margarida De Jesus Dos Santos Narciso; Pedro Damiao de Sousa Henriques

2008-01-01

279

VARIÁVEIS MACROECONÔMICAS E O IBOVESPA: UM ESTUDO DA RELAÇÃO DE CAUSALIDADE  

Microsoft Academic Search

The purpose of this study is to analyze the causality relationship among a sort of selected macroeconomic variables and the return of the Brazilian stock market, using multivariate VAR methodology. The following macroeconomic variables were used in the study: interest rate (SELIC), exchange rate (PTAX) and inflation (IPCA). The Brazilian stock market was represented by the Sao Paulo Stock Index

Tabajara Pimenta Junior; Rene Hironobu Higuchi

280

Fitorremeadição por Brachiaria humidicola de área de disposição de um resíduo perigoso  

Microsoft Academic Search

To evaluate the phytostabilization of a Zn and Cd contaminated industrial residue, it was conducted an experiment with Brachiaria humidicola in a greenhouse, using an alkaline residue (calcium silicate) and an organic residue (sludge from a brewery factory) to reduce the heavy metal solubility in the Ingá residue. The addition of alkaline and organic industrial residues caused a significant reduction

Fabiana Soares dos Santos; Nelson Moura; Amaral Sobrinho; Vinícius Sampaio; Ricardo Bezerra Hoffmann; Nelson Mazur

2005-01-01

281

Gestão da Qualidade nas Agroindústrias: Um Estudo Exploratório no Município de Marau-RS  

Microsoft Academic Search

This research had as objective identifies the quali ty eras, proposed by Garvin (2002), in which the agri-food industry of one city of Brazil (Marau-RS) are framed, as well as to identify the actions executed by these companies, i n relation to the quality management, and the quality tools that these use. For that, an exploratory research was accomplished, and

IVO DE MORAES PASCHE; GABRIEL MURAD; BRASILIENSE DE EDUCAÇ ÃO

282

CitationFinder: Um Sistema Baseado em Conhecimento para Classificação de Páginas de Publicações na Web  

Microsoft Academic Search

http:\\/\\/www.cin.ufpe.br\\/{~mln, ~fab} Abstract. This regularity allows the automatic identification of such pages by computational systems based on domain knowledge. The work presented here describes the CitationFinder, a knowledge-based system for the automatic classification of Web pages which contain citations of technical and scientific publications. The systems counts on a knowledge base of production rules with associated certainty factors, to improve

Mariana Lara Neves; Flávia de Almeida Barros

283

UM CLASSIFICADOR DE FALTAS PARA ANÁLISE DE OCORRÊNCIAS NO SISTEMA CHESF  

Microsoft Academic Search

Artificial Intelligence techniques were used, focusing on artificial neural networks, to the development of a software applied to fault identification and classification in transmission lines. The input data to the neural network are the sampled values of voltage and current waveforms. Those values proceed from the digital fault recorders, which monitor the transmission lines and make the data available in

BENEMAR A. SOUZA; NÚBIA S. D. BRITO; KLEBER M. SILVA; FLÁVIO B. COSTA; CARLOS M. M. FILHO

284

U-M researchers find driver of breast cancer stem cell metastasis  

Cancer.gov

Researchers at the University of Michigan Comprehensive Cancer Center have found that a cancer gene linked to aggressive spread of the disease promotes breast cancer stem cells. The finding implies a new way to target the behavior of these lethal cells. The finding involves the cancer gene RhoC, which has previously been shown to promote metastasis of many types of cancer. RhoC levels increase as breast cancer progresses and high levels of RhoC are associated with worse patient survival.

285

Identification of three absorption bands in the 2-um spectrum of Io  

NASA Astrophysics Data System (ADS)

Spectroscopic observations of the trailing face of Io at a resolution of 1.02/cm performed with the FTS (Fourier Transform Spectrometer) on the 3.6-m Canada-France-Hawaii telescope (CFHT) on Mauna Kea confirm the presence of two weak absorption features in the 2-micron region. The first feature occurs at 4704.9 +/- 0.2/cm (2.12545 +/- 0.00010 micron); it is about 6.8% deep and 3/cm wide (FWHM). The second feature is at 5047.1 +/- 1/cm (1.98135 +/- 0.0004 microns) with a broad central core; its depth is about 8% and its width approximately 7/cm. A laboratory investigation of spectra of solid SO2 with relatively thick samples, as well as of mixtures of SO2 with CO2 and H2S, indicates that the two features at 4705/cm and 5047/cm are best explained by the 3nu1 + nu3 and nu1 + 3nu3 modes of solid SO2 around 130 K, respectively. In addition, a careful a posteriori look at our Io spectrum shows the presence of a band at 3933 +/- 1/cm (2.5426 +/- 0.0007 microns) (depth approximately equal to 30% (full width at half maximum (FWHM) approximately equal to 8/cm) due to the 3V3 band of solid SO2, as predicted by our laboratory experiments. The positions and widths of these bands indicate that a temperature gradient may exist between the surface of the frost and several centimeters below and suggest that some SO2 may be mixed at the molecular level with some neutral component. Three different models are proposed to explain the apparent discrepancy between the large variability with longitude on the strong 2457/cm (4.07 micron band and the nearly constant depth of the weak 4705/cm (2.1254 micron) band. The first model involes a large variation in grain sizes (factor 2-3) over Io's hemispheres. The second model assumes a considerable variation in thermal flux with Io's longitude (at 2457/cm, up to 20% of the reflected continuum flux). The third model assumes an uniform layer of coarse grained SO2 frost (a few hundred micrometers in size) with a variable longitudinal coverage of a thin layer of very fine frost grains (less than a few millimeters of micrometer-sized grains). Using the optical constants of solid SO2 measured in the laboratory, we predict the position and depth (greater than or equal to 1%) of about 25 additional absorption features of SO2 frost, in the 2800-5000/cm (2.0-3.6 micron) range, that should be observed in future high quality spectra of Io.

Schmitt, Bernard; de Bergh, Catherine; Lellouch, Emmanuel; Maillard, Jean-Pierre; Barbe, Alain; Doute, Sylvain

1994-09-01

286

SpectroCam-10: a 10-um spectrograph/camera for the Hale Telescope  

NASA Astrophysics Data System (ADS)

SpectroCam-10 is a 10 micrometers spectrograph and camera built at Cornell University as a facility instrument for the 200 inch Hale telescope. The instrument is optimized for operation from (lambda) equals 8 to 13 micrometers in three modes: a medium-resolution spectrography (R equals (lambda) /(Delta) (lambda) approximately equals 2000), a low-resolution spectrography (R approximately equals 100), and a camera with diffraction limited (0.5 arcsec) spatial resolution. An optical flat and two reflection gratings mounted on a cryogenic rotating mechanism allow rapid switching between modes. The detector is a Rockwell 128 X 128 Si:As Back Illuminated Blocked Impurity Band array. We discuss the design and operation of the instrument, and present some scientific results from our early observing runs at Palomar.

Hayward, Thomas L.; Miles, John E.; Houck, James R.; Gull, George E.; Schoenwald, Justin

1993-10-01

287

Diode-Pumped 1-W Continuous-Wave Er:YAG 3-um Laser.  

National Technical Information Service (NTIS)

We have demonstrated 1.15 W of Gaussian like (M(sup 2) = 2) cw output at 2.94, micrometers from a diode laser end pumped monolithic laser crystal composed of Er doped yttrium aluminum garnet (YAG) bonded to undoped YAG. The laser was pumped with two polar...

D. Chen C. L. Fincher T. S. Rose F. L. Vernon R. A. Fields

1999-01-01

288

Dentine ablation dependency on incident Er:YAG (2.94-um) laser irradiation conditions  

NASA Astrophysics Data System (ADS)

Ablative etch rates within human dentine using an Er:YAG laser have been measured with and without the application of additional water to the sample surface. Projection imaging techniques were found to be useful from both diagnostic and clinical aspects. Well-defined, spatially uniform laser pulses allow accurate determination of ablation threshold fluences as well as fluence-dependent effective absorption coefficients and material removal efficiencies. Etch rate dependency on sample water content is consistent with a thermal ablation mechanism. A model which accounts for this behavior, in view of the temporal pulse structure of the free-running Er:YAG laser, is put forward. The clinical implications of these results are also discussed.

Farrar, Simon R.; Attrill, David C.; Dickinson, Mark R.; King, Terence A.; Blinkhorn, A. S.; Davies, R. M.

1996-12-01

289

Draft Genome Sequence of Dematiaceous Coelomycete Pyrenochaeta sp. Strain UM 256, Isolated from Skin Scraping  

PubMed Central

Pyrenochaeta, classified under the order Pleosporales, is known to cause diseases in plants and humans. Here, we report a draft genome sequence of a Pyrenochaeta sp. isolated from a skin scraping, with an estimated genome size of 39.4 Mb. Genes associated with the synthesis of proteases, toxins, plant cell wall degradation, and multidrug resistance were found.

Yew, Su Mei; Chan, Chai Ling; Soo-Hoo, Tuck Soon; Na, Shiang Ling; Ong, Seong Siang; Hassan, Hamimah; Ngeow, Yun Fong; Hoh, Chee Choong; Lee, Kok Wei; Yee, Wai Yan

2013-01-01

290

Tunable fiber laser source for methane detection at 1.68 um  

Microsoft Academic Search

A tunable fiber laser for spectroscopic gas detection is reported for the first time. The laser is based on a single-mode thulium doped fiber, which can operate at a wavelength around 1.684 micrometers , corresponding to a significant absorption line for methane. The fiber laser was pumped at 786 nm, a wavelength which is readily available with AlGaAs laser diodes

William L. Barnes; John P. Dakin; Henry O. Edwards; Laurence Reekie; Janet E. Townsend; Stuart C. Murray; David Pinchbeck

1993-01-01

291

Wideband channelized receiver possibilities with 0.18-um CMOS technology  

NASA Astrophysics Data System (ADS)

Channelized receivers are useful in communications systems that use frequency division multiplexing, and in wideband radar and electronic warfare receivers. In present wideband communications equipment, the channelization function is done typically with discrete elements such as mixers and surface acoustic wave (SAW) bandpass filters on a single channel basis. Recently much activity has been directed to using digital techniques and devices to make smaller, cheaper receivers. Following this trend, this paper exploits the 'Timeline' 0.18 micron CMOS technology recently announced by Texas Instruments and show the bandwidths, levels of system integration, and package sizes that become possible with the Timeline technology. The design example shown is a digital channelizer for a system with 150 MHz total bandwidth including 60 channels on 2.5 MHz channel centers. A polyphase filter bank algorithm with 6x oversampling compared to the channel spacing is used. The design is suitable for a burst communication receiver. With the Timeline technology, an ASIC that implements two maximally decimated filter banks at the above bandwidths is shown. The ASIC fits onto a 20 mm by 20 mm die and consumes about 7 watts. Three such ASICs are then needed to implement the complete 6x oversampled filter bank, which will output 60 complex channels at 15 MSPS for about 20 watts.

McWilliams, Joel K.; Wentzel, Scott W.

1998-01-01

292

O olhar da equipe e usuários de um hospital geral sobre a necessidade de intervenção psicológica  

Microsoft Academic Search

The intervention of the psychology professional in the hospital context is becoming more and more necessary and common. In view of this, the present article is a research report that was carried out in a public hospital in Santa Maria city in the Rio Grande do Sul state. It aims to analyses the expectations of the health staff and users

Jossiele Fighera; Eliani Venturini Viero

293

Automacao, desenvolvimento e performance de um espectrometro fotoacustico. (Automation, development and performance of a photoacoustic spectrometer).  

National Technical Information Service (NTIS)

This work consists in the development of a circuit to interface a photoacoustic spectrometer with a microcomputer. The obtained spectra are identical to those obtained in commercial photoacoustic spectrometers. The system permits a great versatility and i...

F. R. F. Cavalheiro

1985-01-01

294

Contact hole patterning performance of ArF resist for 0.10 um technology node  

NASA Astrophysics Data System (ADS)

For the fabrication of IC devices, the patterning of C/H (contact holes) is essential but very difficult in comparison with L/S (lines and spaces). 193nm lithography following KrF lithography is expected to play a main role in 0.1micrometers technology node. However, many lithographers have reported various troubles such as poor profiles, resist shrinkage, and pattern edge roughness due to inherent flaws of ArF resist materials. In this study, we noticed such complex issues relating to patterning C/H and evaluated two resists (acrylate, ROMA), which are promising materials among ArF resists, at the condition of various baking temperatures of the soft bake and the post exposure bake. And then we investigated lithographic capability (resolution limit, exposure latitude, depth of focus, and CD uniformity) at the optimum bake conditions. Besides, the resist flow properties were estimated on both resists, respectively. Throughout experimentals, we were able to observe ArF resist properties for bake conditions and find optimum temperatures to improve several issues occurred on C/H pattern. Thus we directly achieved 0.12~0.10 micrometers C/H and also decade- nanometer C/H by applying the resist flow process.

Kim, Jin-Soo; Jung, Jae Chang; Kong, Keun-Kyu; Lee, Geunsu; Lee, Sung-Koo; Hwang, Young-Sun; Shin, Ki-Soo

2002-07-01

295

Application of 2-um wavelength holmium lasers for treatment of skin diseases  

NASA Astrophysics Data System (ADS)

Theoretical and experimental analysis of the efficiency of application of 2 micrometers pulsed holmium laser for cosmetic and plastic surgery and dermatology is carried out. Preliminary experiments were carried out on rats. Solid state 2 micrometers pulsed laser was allowed to operate in free running mode with pulse energy up to 1.5 J and pulse repetition rate up to 5 Hz. To deliver emission to the object a flexible quartz fiber without further focusing of 2.5 m in length and 400 micrometers of the core diameter was used. The effect of the different power density emission on the skin was studied. The second stage was the study of the influence of 2 micrometers emission on human skin. The results of the removal of hemangioma, papilloma, telangiectasia, nevus, nevus acantholytic, xanthelasma palpebral, verruca, chloasma, pigmental spots, tattoos, etc. are presented. Precision, simplicity, efficiency, and the high cosmetic effect of these operations is noted.

Shcherbakov, Ivan A.; Klimov, Igor V.; Tsvetkov, Vladimir B.; Nerobeev, Alexander I.; Sadovnikova, Lija B.; Eliseenko, Vladimir I.

1994-09-01

296

Portable optoelectronic gas sensors operating in the mid-IR spectral range (lambda=3 5 um)  

Microsoft Academic Search

Recently developed mid-IR LED non-dispersive gas analyzers can replace conventional infrared gas monitors. The advantages of novel analyzers are compact size, fast response and low power consumption. InAsSb(P)- and InGaAs(Sb)-based LEDs developed and manufactured at Ioffe Physico-Technical Institute suit for optical gas sensing well because of narrow emission band and the possibility of making LED emission peak spectrally matched with

S. E. Alexandrov; Gennadii A. Gavrilov; A. A. Kapralov; Sergey A. Karandashev; Boris A. Matveev; Galina Y. Sotnikova; Nikolai M. Stus

2002-01-01

297

Um Sistema de Banco de Dados Replicado Gerenciado através de Applets Distribuídas  

Microsoft Academic Search

A distributed and replied database it is characterized as a collection of several similar databases, logically connected through a computers net. This work has as proposal the definition, administration and implementation of a distributed and replied database that uses several databases in different servers. Therefore, the distributed transactions, width concurrency control, are executed through the same software in the different

André Luis; Castro de Freitas

298

 

PubMed

O método Grade of Membership (GoM) tem sido cada vez mais utilizado por demógrafos brasileiros e tem a vantagem de possuir um parâmetro que mensura a heterogeneidade individual, com base nas correlações não-observáveis entre as categorias de resposta das variáveis de interesse, gerando um medida do grau de pertencimento de cada indivíduo a perfis extremos. Alguns autores, contudo, chamam atenção para questões importantes na calibragem dos modelos finais que utilizam o programa GoM versão 3.4, como o problema de identificabilidade - soluções múltiplas para parâmetros estimados. Neste artigo, é sugerido um procedimento capaz de identificar um modelo final com solução única que descreva os tipos puros mais fidedignos à base de dados, em uma tentativa de otimização. Para ilustrar esse processo, utilizou-se uma base de dados correspondente a um levantamento econômico e sociodemográfico de uma população de pequenos agricultores residentes ao longo da Rodovia Transamazônica, no Estado do Pará. Também identificou-se a existência de instabilidade nos parâmetros estimados pelo programa GoM 3.4, sendo proposto um método de estabilização de seus valores. Com esses procedimentos combinados, os usuários do programa GoM 3.4 poderão descrever sua base de dados de forma mais adequada e responder às críticas sobre questões de identificabilidade e estabilidade dos modelos resultantes. Essas soluções empíricas são relevantes por afetarem cálculos de prevalência e de incidência de eventos de interesse, além de trazerem consequências importantes sobre o ponto e o momento corretos para intervenções de políticas públicas ou de planejamento prospectivo em análises de projeção. PMID:21709732

Guedes, Gilvan Ramalho; Caetano, André Junqueira; Machado, Carla Jorge; Brondízio, Eduardo Sonewend

2010-01-01

299

Controle orbital de satélites artificiais com propulsão e uso de gravidade lunar  

NASA Astrophysics Data System (ADS)

A redução do custo de combustível de uma manobra é atualmente a grande prioridade de todos os programas espaciais existentes no mundo. As manobras assistidas pela gravidade são uma ótima forma de se contornar o problema pois proporcionam economias com vasto impacto no custo final da missão. Neste trabalho é feito um estudo particular do controle orbital de um satélite artificial da Terra usando a gravidade da Lua. O objetivo é estudar uma técnica econômica para uma mudança de plano de um satélite que está em órbita em volta da Terra. A idéia principal desta abordagem é enviar primeiramente o veículo espacial em direção à Lua usando uma manobra mono-impulsiva para que assim o campo gravitacional da Lua possa fazer a mudança de plano desejada (sem custo de combustível) e só então retornar o veículo aos valores iniciais de semi-eixo e excentricidade usando uma manobra bi-impulsiva tipo Hohmann. Para tanto, é assumido que a espaçonave inicia em uma órbita circular coplanar à órbita da lua em torno da Terra e a meta é colocá-la em uma órbita similar que difere da órbita inicial somente pela inclinação. São usadas equações analíticas baseadas na abordagem Patched Conics para se calcular a variação na velocidade, momento angular, energia e inclinação do veículo espacial que realiza esta manobra. Várias simulações são feitas para se avaliar as economias de combustível envolvidas.

Torres, K. S.; de Almeida Prado, A. F. B.

2003-08-01

300

Captura de satélites durante a formação de Júpiter  

NASA Astrophysics Data System (ADS)

O planeta Jupiter apresenta um grande número de satélites irregulares. As características das órbitas destes objetos indicam que os mesmos não teriam se formado ao redor do planeta que se encontram. As teorias existentes são de que estes objetos teriam se formado em uma região distante do planeta e sua evolução dinâmica os teria levado a uma captura gravitacional pelo planeta. Tendo em vista que o processo de captura gravitacional sem efeitos dissipativos não produz uma captura permanente, estudamos o processo de captura durante o estágio de formação do planeta. Realizamos simulações numéricas para os casos de satélites prógrados e retrógrados que inicialmente se encontram ao redor de Jupiter com sua massa atual e então, evoluimos a integração voltando no tempo de modo que o planeta sofra uma redução em sua massa (de 100% para 10% de sua massa atual) e verificamos o instante em que o satélites escapa do planeta (quando sua energia do problema de dois corpos se torna positiva). Assim, analisando o problema inverso no tempo, obtivemos em qual estágio de formação de Jupiter aquele hipotético satélite teria sido capturado. Os resultados mostram que os satélites retrógrados são capturados assim que entram na região delimitada pela esfera de Hill do planeta, enquanto que os satélites prógrados só são capturados quando entram numa região bem mais próxima ao planeta, uma fração da esfera de Hill.

Winter, O. C.; Vieira Neto, E.; Yokoyama, T.

2003-08-01

301

On efeito do achatamento nos pontos de equilíbrio e na dinâmica de sistemas coorbitais  

NASA Astrophysics Data System (ADS)

Neste trabalho analisamos o efeito do achatamento do corpo principal nos pontos de equilíbrio lagrangianos e na configuração de órbitas girino-ferradura. Enfatizamos os sistemas coorbitais de satélites de Saturno, pois se encontram em relativa proximidade com o planeta, em que o efeito do achatamento se torna mais evidente. O estudo é dividido em três etapas independentes. Na primeira fase analisamos as equações de movimento do problema restrito de três corpos considerando o efeito do achatamento, e através do balanceamento de forças buscamos a nova configuração dos pontos de equilíbrio lagrangianos. Concluímos, nesta etapa, que os pontos de equilíbrio estáveis apresentam um pequeno deslocamento definido pelo parâmetro de achatamento, não podendo ser mais representados por triângulos eqüiláteros. Aplicamos este resultado aos satélites coorbitais de Tetis e Dione, encontrando as posições de equilíbrio levemente deslocadas em relação ao caso sem achatamento. Na segunda fase visamos o sistema Saturno-Jano-Epimeteu, que por se tratar de um sistema de massas comparáveis, optamos por desenvolver as equações de Yoder et al (Icarus 53, pág 431-443, 1983), que permitem determinar os pontos de equilíbrio e a amplitude de oscilação angular das órbitas girino-ferradura para o problema não-restrito de três corpos, porém, no nosso estudo consideramos o efeito do achatamento do corpo principal nestas equações. Encontramos que a distância angular entre satélites, quando em posição de equilíbrio estável, diminui quanto maior for o parâmetro de achatamento do corpo principal. Além disso, a órbita de transição girino-ferradura possui largura angular menor em relação ao caso sem achatamento. Por fim, realizamos integrações numéricas para os casos reais de coorbitais de Saturno comparando com os resultados analíticos. Nestas integrações simulamos diversas órbitas girino-ferradura com diferentes parâmetros de achatamento, utilizando condições iniciais corrigidas para a presença do achatamento.

Mourão, D. C.; Winter, O. C.; Yokoyama, T.

2003-08-01

302

Spectral classification of rocks: analysis of laboratory 0.4- to 2.5-um reflectance and 2.5- to 25-um transmittance spectra of sedimentary and metamorphic rocks  

NASA Astrophysics Data System (ADS)

Reflectance (0.4 - 2.5 micrometer) and transmittance (2.5 - 25 micrometer) laboratory spectra of sedimentary and metamorphic rocks from different geologic settings were analyzed and classified, and used for the simulation of hyperspectral (MIVIS) response. The analysis regarded both freshly cut and exposed rock surfaces. Classification was based on absorption features forming significant associations that fully characterized groups of rocks. In carbonate rocks, the dominant spectral features in the VIS-NIR resulted from the fundamental mineralogy, whereas within overall silicatic rocks the discrimination was based on secondary mineralogic phases, that resulted spectrally dominant. In transmission spectra of silicatic rocks, spectrally dominant features, due to different bounding of Si4+ ion, allowed further differentiation between rocks not discriminated in the reflectance spectra. Classification of spectra of exposed surfaces did not significantly diverge from that of the freshly cut surfaces, apart from heavy lichen coating.

Chiari, Roberto; Longhi, Ilaria; Sgavetti, Maria A.; Gelli, Anna; Orsi, Andrea; Pecoraro, Fabrizio

1997-12-01

303

Nd:YAP 1.34 um/1.08 um laser passively mode-locked/Q-switched by V3+:YAG/BDN II saturable absorbers with efficient COP/AG hollow glass waveguide radiation delivery  

NASA Astrophysics Data System (ADS)

A compact, passively Q-switched and mode-locked Nd:YAP laser in oscillator- amplifier configuration was designed and constructed. Operation wavelength switching (between 1.34 and 1.08 micrometers ) was achieved with a three-mirror cavity and mechanical shutter. For Q switching and mode locking of the 1.34-micrometers Nd:YAP laser transition, a V3+-doped yttrium aluminum garnet (YAG) saturable absorber was employed. The optimal performance was found after variation of the resonator length (40 to 100 cm) and of the absorber initial transmission (52% to 89%). The duration of a single pulse in a train was around 1 ns. The saturation intensity of the V3+:YAG absorber was determined to be 10 MW/cm2. A BDN II polymer thin-film saturable absorber was used for Q switching the 1.08-micrometers laser transition. After amplification, the maximum output energy reached was 27 mJ (train of mode-locked pulses at 1.34 micrometers ) or 94 mJ (Q-switched pulse at 1.08 micrometers ). The output laser radiation was delivered by means of a hollow glass waveguide coated with cyclic olefin polymer and Ag, with 95% and 80% efficiencies for 1.34 and 1.08 micrometers , respectively.

Jelinkova, Helena; Cerny, Pavel; Sulc, Jan; Jabczynski, Jan K.; Kopczynski, Krzysztof; Mierczyk, Zygmunt; Miyagi, Mitsunobu; Matsuura, Yuji; Shi, Yi-Wei

2002-08-01

304

Ti.n-Palladi.um Catalysts for Electroless Plating THEIR WIDESPREAD USE DURING THE COATING OF NON-CONDUCTING SUBSTRATES  

Microsoft Academic Search

The application of electroless plating as a surface coating technique for producing both functional and decorative finishes has increascd sub- stantially with the growth in the requirement for printed circuit boards, and with the widespread use of plastics for so many purposes. nuring the plating process a thin layer o,f catalyst is applied to the dielectric surface and n layer

Gerald A. Krulik

305

Acompanhamento do crescimento em crianças menores de um ano: situação nos serviços de saúde em Pernambuco, Brasil  

Microsoft Academic Search

A situational diagnosis was performed on infant growth monitoring in Greater Metropolitan Rec- ife and in the interior of the State of Pernambu- co, Brazil, using the database from the Survey on Maternal and Child Health in the State of Per- nambuco, 1998, which included 816 infants (< 1 year of age) and 120 health units. Epi Info ver- sion

Michelle Figueiredo Carvalho; Pedro Israel Cabral de Lira; Sylvia de Azevedo Mello Romani; Iná S. Santos; Ana Amélia Corrêa de Araújo Veras; Malaquias Batista Filho

2008-01-01

306

Chemical optimization of resist/developer systems tuned for sub-0.4-um process window expansion  

NASA Astrophysics Data System (ADS)

In order to perform 0.2 micrometer processes, one needs to study the diffusion of photoacid generators within the photoresist system, since diffusion during post exposure bake time has an influence on the critical dimension (CD). We have developed a new method to study the diffusion of photoacid generators within a polymer film. This new method is based on monitoring the change of the fluorescence intensity of a pH- sensitive fluorescent dye caused by the reaction with photoacid. A simplified version of this experiment has been conducted by introducing acid vapor to quench the fluorescence intensity of this pH sensor. A thin polymer film is spin cast onto the sensor to create a barrier to the acid diffusion process. During the acid diffusion process, the fluorescence intensity of this pH sensor is measured in situ, using excitation and emission wavelengths at 466 nm and 516 nm, respectively. Fluoresceinamine, the pH sensitive fluorescent dye, is covalently bonded onto the treated quartz substrate to form a single dye layer. Poly(hydroxystyrene) (Mn equals 13k, Tg equals 180 degrees Celsius) in PGMEA (5% - 18% by weight) is spin cast onto this quartz substrate to form films with varying thickness. The soft bake time is 60 seconds at 90 degrees Celsius and a typical film has a thickness of 1.4 micrometers. Trifluoroacetic acid is introduced into a small chamber while the fluorescence from this quartz window is observed. Our study focuses on finding the diffusion constant of the vaporized acid (trifluoroacetic acid) in the poly(hydroxystyrene) polymer film. By applying the Fick's second law, (It - Io)/(I(infinity ) - Io) equals erfc [L/(Dt)1/2] is obtained. The change of fluorescence intensity with respect to the diffusion time is monitored. The above equation is used for the data analysis, where L represents the film thickness and t represents the average time for the acid to diffuse through the film. The diffusion constant is calculated to be at the order of 10-10 cm2/s to 10-12 cm2/s. All the experiments are conducted at room temperature and are valid only for acid vapor. With different film thickness, it was found that the acid diffuses through the film with a similar diffusion constant. The diffusion is faster with increased solvent residue in the film (controlled by spin coating speed). The theoretical computer modeling of the local acid concentration with respect to acid diffusion is also performed.

Toukhy, Medhat A.; Schlicht, Karin R.; Tarbox, Kimberly

1997-07-01

307

U-M study finds inflammatory pathway spurs cancer stem cells to resist HER2-targeted breast cancer treatment  

Cancer.gov

Breast cancer treatments such as Herceptin that target a marker called HER2 have dramatically improved outcomes for women with this type of cancer. But nearly half of these cancers are resistant to Herceptin from the start and almost all of them will eventually become resistant. Now, researchers at the University of Michigan Comprehensive Cancer Center have discovered one reason why the cancer cells become resistant: They turn on a completely different pathway, one that is involved in inflammation, fueling the cancer independently of HER2.

308

SKEMA - Um codigo de computador para estimar dispersao atmosferica. (SKEMA - A computer code to estimate atmospheric dispersion).  

National Technical Information Service (NTIS)

This computer code is a modified version of DWNWND code, developed in Oak Ridge National Laboratory. The Skema code makes an estimative of concentration in air of a material released in atmosphery, by ponctual source. (C.M.). (Atomindex citation 21:067132...

A. M. Sacramento

1985-01-01

309

Optimization for Axial Resolution, Depth Range, and Sensitivity of Spectral Domain Optical Coherence Tomography at 1.3 um  

PubMed Central

We have developed high-speed and high-resolution spectral domain optical coherence tomography at 1.3 µm using an InGaAs line-scan camera and a broadband light source with the bandwidth of 170 nm that produces a theoretical axial resolution of 4.4 µm in air. We compared axial resolutions from point spread functions (PSFs) and depth ranges while changing the full spectral bandwidth detected by the camera and describing the optimization process for the axial resolution, the depth range, and the sensitivity for SD-OCT system. We found that SD-OCT at 1.3 µm cannot satisfy the conditions both below the axial resolution of 5 µm and above the depth range of 2 mm because of the restricted pixel number of the line-scan camera. To scan a large depth range, the axial resolution has to be sacrificed. In addition, the sensitivity rolls off slowly as a function of the depth if a large depth range is scanned. On the other hand, if the axial resolution needs to be close to the theoretical one, the depth range becomes limited and the sensitivity decays quickly. Since we have to maintain a reasonable depth range of 2.0 mm, we chose the spectrum full bandwidth of 214 nm captured by the detector to balance the axial resolution of 8.2 µm. In this setting, the sensitivity of our OCT system was measured at 107.1 dB. Theoretical and experimental results are compared and presented in this paper.

Lee, Sang-Won; Jeong, Hyun-Woo; Kim, Beop-Min; Ahn, Yeh-Chan; Jung, Woonggyu; Chen, Zhongping

2012-01-01

310

8.5-um room temperature quantum cascade lasers grown by gas-source molecular beam epitaxy  

Microsoft Academic Search

We report room-temperature pulsed-mode operation of 8.5 micrometers quantum cascade lasers grown by gas-source molecular beam epitaxy. The theory necessary to understand the operation of the laser is presented and current problems are analyzed. Very good agreement is shown to exist between theoretical and experimental emission wavelengths. The high- temperature operation is achieved with 1 microsecond(s) pulses at a repetition

Steven Slivken; Manijeh Razeghi

1998-01-01

311

CONTINUOUS MEASUREMENT OF PARTICLES (0.01-20.0 UM) IN AN OCCUPIED HOME, REED AND WALLACE, AAAR.  

EPA Science Inventory

To better understand the contribution of outdoor and indoor sources to particle concentrations found in residential indoor air, an extensive monitoring effort has been undertaken in a three-story townhouse located in Reston, VA. Of particular interest was the determination of i...

312

Proposta de Um Sistema Semi-Automatico Para Teste de Programas (Proposal for a Semiautomatic Program Testing System).  

National Technical Information Service (NTIS)

This work reflects the effort towards the development of software tools to be used in the selection of testing data for FORTRAN programs. An interactive system is described for analyzing programs which provides the user, at the end of an execution of a gi...

N. C. D. Ferreira

1984-01-01

313

Proposta de Um Sistema de Software Para Teste de Satelites (Proposal of a Software System for Satellite Testing).  

National Technical Information Service (NTIS)

In contribution to the development of the Banco de Teste (BT), which is a satellite test system, this work aims to present the survey of the functional requirements for the satellite testing specific software of the BT and to propose a method to be follow...

G. M. Ambroz

1987-01-01

314

Fatigue behavior in water of Y-TZP zirconia ceramics after abrasion with 30 um silica-coated alumina particles  

PubMed Central

Objective The use of a 30 µm alumina–silica coated particle sand (CoJet™ Sand, 3M Espe), has shown to enhance the adhesion of resin cements to Y-TZP. The question is whether or not sandblasting 30 µm particles does negatively affect the fatigue limit (S–N curves) and the cumulative survival of Y-TZP ceramics. Method Four zirconia materials tested were: Zeno (ZW) (Wieland), Everest ZS (KV) (KaVo), Lava white (LV) and Lava colored (LVB) (3M Espe). Fatigue testing (S–N) was performed on 66 bar of 3 mm × 5 mm × 40 mm with beveled edges for each zirconia material provided by the manufacturers. One half of the specimens were CoJet sandblasted in the middle of the tensile side on a surface of 5 mm × 6 mm. Cyclic fatigue (N = 30/group) (sinusoidal loading/unloading at 10 Hz between 10% and 100% load) was performed in 3-point-bending in a water tank. Stress levels were lowered from the initial static value (average of N = 3) until surviving 1 million cycles. Fatigue limits were determined from trend lines. Kaplan–Meier survival analysis was performed to determine the failure stress at the median percentile survival level for 1 million of cycles before and after sandblasting. The statistical analyses used the log-rank test. Characterization of the critical flaw was performed by SEM for the majority of the failed specimens. Results The fatigue limits “as received” (ctr) were: LV = 720 MPa, LVB = 600 MPa, KV = 560 MPa, ZW = 470 MPa. The fatigue limits “after CoJet sandblasting” were: LV = 840 MPa, LVB = 788 MPa, KV = 645 MPa, ZW = 540 MPa. The increase in fatigue limit after sandblasting was 15% for Zeno (ZW) and Everest (KV), 17% for Lava (LV) and 31% for Lava colored (LVB). The KM median survival stresses in MPa were: ZW(ctr) = 549 (543–555), ZW(s) = 587 (545–629), KV(ctr) = 593 (579–607), KV(s) = 676 (655–697), LVB(ctr) = 635 (578–692), LVB(s) = 809 (787–831), LV(ctr) = 743 (729–757), LV(s) = 908 (840–976). Log-rank tests were significantly different (p < 0.001) for all sandblasted groups vs. the “as received” except for Zeno (Wieland) (p = 0.295). Failures started from both intrinsic and machined flaws. Significance 30 µm particle sandblasting did significantly improve the fatigue behavior of three out of four Y-TZP ceramic materials and can therefore be recommended for adhesive cementation procedures. This study was supported in part by grants from the Swiss Society for Reconstructive Dentistry (SSRD) and 3M Espe.

Scherrer, Susanne S.; Cattani-Lorente, Maria; Vittecoq, Eric; de Mestral, Francois; Griggs, Jason A.; Wiskott, H.W. Anselm

2011-01-01

315

Raman-shifted alexandrite laser for soft tissue ablation in the 6- to 7-um wavelength range  

PubMed Central

Prior work with free-electron lasers (FELs) showed that wavelengths in the 6- to 7-µm range could ablate soft tissues efficiently with little collateral damage; however, FELs proved too costly and too complex for widespread surgical use. Several alternative 6- to 7-µm laser systems have demonstrated the ability to cut soft tissues cleanly, but at rates that were much too low for surgical applications. Here, we present initial results with a Raman-shifted, pulsed alexandrite laser that is tunable from 6 to 7 µm and cuts soft tissues cleanly—approximately 15 µm of thermal damage surrounding ablation craters in cornea—and does so with volumetric ablation rates of 2–5 × 10?3 mm3/s. These rates are comparable to those attained in prior successful surgical trials using the FEL for optic nerve sheath fenestration.

Kozub, John; Ivanov, Borislav; Jayasinghe, Aroshan; Prasad, Ratna; Shen, Jin; Klosner, Marc; Heller, Donald; Mendenhall, Marcus; Piston, David W.; Joos, Karen; Hutson, M. Shane

2011-01-01

316

Menarca, gravidez precoce e obesidade em mulheres brasileiras selecionadas em um Centro de Saúde de Belo Horizonte  

Microsoft Academic Search

The aim of this study was to investigate obstetric variables potentially associated wit h obesity among 486 Brazilian childbearing-age women aged 15-59 residing in the municipality o f Belo Horizonte, Minas Gerais State. Body fat (BF) was measured through impedance analysis , and obesity was defined as BF ? 30%. The association between obstetrics factors and obesity wa s evaluated

317

In vitro comparison of the vaporesection of human benign prostatic hyperplasia using 70- and 120-W 2-um lasers  

PubMed Central

The purpose of the current ex vivo study was to compare the speed of vaporesection of human prostatic tissue with benign prostatic hyperplasia (BPH) and the depth of tissue damage using 70- and 120-W 2-µm laser devices. Fresh prostatic tissue specimens were obtained from five patients by open prostatectomy, and were divided into separate groups (70 and 120 W) based on the energy of the laser output (70 and 120 W, respectively). The vaporesection speed, coagulation zone depth and the necrotic tissue layer in the prostatic tissue were evaluated. The current result showed that the speeds (mean±s.d.) of vaporesection were 5.21±0.66 and 10.39±1.15 g/5 min for the 70 and 120 W groups, respectively (P=0.000). There was no difference in the depth of necrosis/coagulation (0.98±0.13/0.30±0.09 and 0.99±0.12/0.31±0.08 mm) for the 70 and 120 W groups, respectively. In conclusion, both 70- and 120-W 2-µm laser devices had superficial tissue damage during the vaporesection of human prostate tissue; moreover, the 120-W laser offers a higher vaporesection speed than the 70-W laser.

Luo, Guang-Heng; Xia, Shu-Jie; Sun, Zhao-Lin

2011-01-01

318

Combined 1.06- and 1.32-um Nd:YAG laser in the treatment of rectosigmoideal tumors  

NASA Astrophysics Data System (ADS)

Since January 1988 we have been using the combined Nd:YAG laser Medicalas. The laser operates on the wavelength of 1.06 micrometers with maximum output power of 100 W, and a wavelength of 1.32 micrometers with maximum output power of 30 W. Introduction of the laser into clinical practice was preceded by experimental operation, where we verified the interaction of laser emittance on both wavelengths with the tissues of colon, stomach, esophagus, and open surgery of the abdominal and thoracic cavities.

Horak, Ladislav; Fanta, J.; Marek, Jan

1993-07-01

319

Design and research of RS232 communication circuit used for 0.6um CMOS sensor IC  

Microsoft Academic Search

A RS232 transmitter interface circuit used for CMOS sensor IC has been developed in a 0.6mum CMOS technology, which makes it possible to integrate CMOS sensors and subsequent signal processing and communication interface circuits in a single chip. The positive and negative voltages (+7.6V\\/-6.1V under +5V single supply) are achieved with on-chip charge pump, which are used as supply of

Sun-Ying; Zhu-Dazhong

2006-01-01

320

A Study of Similarity Functions in the Planetary Boundary Layer Um Estudo das Funcoes de Similaridade DA Camada Limite Planetaria.  

National Technical Information Service (NTIS)

Micrometeorological data obtained over tropical savannah (Koorin Experiment, 16 deg 16'S; 133 deg 23'E, Australia) were used to evaluate the similarity functions A, B and C in the planetary boundary layer. Different flux profile relationships, and scaling...

J. C. S. Chagas

1982-01-01

321

Room temperature continuous wave InGaAsN quantum well vertical cavity lasers emitting at 1.3 um  

SciTech Connect

Selectively oxidized vertical cavity lasers emitting at 1294 nm using InGaAsN quantum wells are reported for the first time which operate continuous wave at and above room temperature. The lasers employ two n-type Al{sub 0.94}Ga{sub 0.06}As/GaAs distributed Bragg reflectors each with a selectively oxidized current aperture adjacent to the optical cavity, and the top output mirror contains a tunnel junction to inject holes into the active region. Continuous wave single mode lasing is observed up to 55 C. These lasers exhibit the longest wavelength reported to date for vertical cavity surface emitting lasers grown on GaAs substrates.

CHOQUETTE,KENT D.; KLEM,JOHN F.; FISCHER,ARTHUR J.; SPAHN,OLGA B.; ALLERMAN,ANDREW A.; FRITZ,IAN J.; KURTZ,STEVEN R.; BREILAND,WILLIAM G.; SIEG,ROBERT M.; GEIB,KENT M.; SCOTT,J.W.; NAONE,R.L.

2000-06-05

322

High-speed laser diagnostics at 1.06 um with simultaneous percussion hole drilling of aerospace materials  

NASA Astrophysics Data System (ADS)

A diagnostic system was designed, fabricated and tested for measuring a Nd:YAG laser's performance using a five-axis laser machining center. Far field beam profile, beam quality, beam tilt and beam power were measured at high frequencies while holes were simultaneously percussion drilled in aerospace materials used in gas turbine engines. The system allowed determination of effects of varying laser and machine operating parameters on materials processing performance. Variations were made in laser pulse length, pulse energy, pulse repetition rate, drilling standoff distances from part, incident angles and other parameters. Measured laser beam performance was compared directly with drilled holes. A number of identically drilled holes provided hole-to-hole variance, allowing the machine center operators to optimize materials processing by tuning the laser operating parameters. The results also gave the operator additional understanding of variations of processing performance.

Cunningham, Philip R.; Fahndrich, Marc; Oliver, Jeffrey W.; Bertlesen, Thomas S.; Frye, Richard W.

1993-06-01

323

Elemental analysis of natural quartz from Um Higlig, Red Sea Aea, Egypt by instrumental neutron activation analysis.  

PubMed

A scheme for INAA of 25 elements: As, Ba, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sc, Sm, Th, U, Yb, Zn and Zr in quartz collected from the eastern desert along the Egyptian Red Sea coast is proposed. The samples were prepared together with standard reference material and irradiated in a neutron flux of 7×10(11)n/cm(2)s in the TRIGA Mainz research reactor facilities. The gamma spectra were collected by a HPGe detector and the analysis was done by a computerized multichannel analyzer.The accuracy of the procedure is evaluated by the analysis of two geo-standard reference materials (Dolerite WSE and Microgabro PMS). The choice of the nuclear reaction, irradiation and decay times and of the proper gamma radiation in counting are presented and discussed. The data presented here are our contribution to understanding the elemental composition of the quartz rock. Because there are no existing databases for the elemental analysis of quartz, our results are a start to establishing a database for the Egyptian quartz. It is hoped that the data presented here will be useful to those dealing with geochemistry, quartz chemistry and related fields. PMID:23954747

El-Taher, A; Alharbi, Abdulaziz

2013-12-01

324

High-power InAsSb/InAsSbP laser diodes emitting at 3- to 5-um range  

NASA Astrophysics Data System (ADS)

We report metalorganic chemical vapor deposition-grown double heterostructure and multiple quantum well InAsSb/InAsSbP laser diodes emitting at 3 to 4 micrometers and light emitting diodes up to 5 micrometers . Maximum output power up to 1 W was obtained from a MQW laser with stripe width of 100 micrometers and cavity length of 700 micrometers for emitting wavelength of 3.6 micrometers at 90 K. Maximum operating temperature up to 220 K with threshold current density of 40 A/cm2 at 78K were achieved from the double- heterostructure lasers emitting at 3.2 micrometers . The far-field beam divergence as narrow as 24 degrees was achieved with the sue of higher energy gap barrier layers, i.e., lower effective refractive index, in MQW active region. We also discuss the effect of composition-fluctuation in the InAsSb active region on the gain and threshold current of the lasers.

Razeghi, Manijeh; Diaz, Jaqueline; Yi, Hyuk J.; Wu, D.; Lane, B.; Rybaltowski, A.; Xiao, Y. H.; Jeon, H.

1997-01-01

325

Colchicina no tratamento da fase inflamatória da oftalmopatia de Graves: um estudo prospectivo e randomizado com prednisona  

Microsoft Academic Search

Purpose: To investigate if colchicine is valuable in the treatment of Graves' ophthalmopathy (GO), we compared its effect with prednisone in 22 patients during the inflammatory phase of GO. Methods: All patients, similar in age, sex and smoking habits, were euthyroid for at least 3 months and randomly divided into two groups, one treated with colchicine (1.5 mg\\/day) and the

Paulo Gois Manso; Ângela Maria Borri Wolosker; Elias Rodrigues de Paiva; Antonio Carlos Lopes; Reinaldo Perrone Furlanetto

326

Mass spectrometric analysis of evolved CO2 during 9.6-um CO2 irradiation of dental enamel  

NASA Astrophysics Data System (ADS)

Carbon dioxide laser irradiation induces chemical changes in dental hard tissues including, dehydration, decomposition, disproportionation, and vaporization. Such changes can lead to either an increase or decrease in susceptibility to acid dissolution and adversely affect the bond strength to restorative materials. The objective of this study was to measure the evolved molecular species produced during laser irradiation. Samples of bovine enamel were irradiated by a 9.6 micrometers TEA CO2 laser in a vacuum chamber connected to a quadruple mass spectrometer. At irradiation intensities above 0.37 J/cm2 an increase in evolved CO2 and H2O were detected indicative of thermal decomposition of the mineral phase. The respective ion yields changed markedly with increasing number of laser pulses suggesting that the decomposition was complete after less than ten laser pulses at irradiation intensities from 0.4 to 0.8 J/cm2. Above irradiation intensities of 1.0 J/cm2 there is continual emission after 50 laser pulses indicative of vaporization and material removal. At higher ablative fluence, higher mass species were detected due to the ejection of hydroxyapatite. This study demonstrates that mass spectroscopy can be used to directly probe laser induced physical and chemical changes in dental hard tissue during laser ablation.

Xie, John; Fried, Daniel

2002-06-01

327

Thermal and chemical modification of dentin by pulsed CO2 laser irradiation at 9 to 11 um  

NASA Astrophysics Data System (ADS)

Previous studies have shown that dentin can be thermally modified by pulsed CO2 laser irradiation to form a more highly mineralized tissue. The implications are important for the potential laser modification or removal of dentinal and root caries. Temperature excursions were followed after (lambda) equals 9.3, 9.6, 10.3, and 10.6 micrometers laser irradiation with pulses of 100 (Mu) s duration at irradiation intensities of 0.5 to 8 J/cm2. In addition, photoacoustic and transient reflectance measurements were used to monitor the loss of water and organics and to detect the thresholds for surface modification and tissue ablation. The surface temperatures of dentin were markedly higher than those measured on enamel for similar irradiation intensities due to the lower reflectance losses of dentin and the lower thermal diffusivity at the respective wavelengths. Hence, lower fluences are required for the thermal decomposition of dentin. Ablation typically occurred with the first few laser pulses during multiple pulse irradiation and eventually ceased after modification of dentin to a more hypermineralized tissue. The debris ejected during the initial laser pulses shielded the surface by as much as 60 percent at the low fluences employed in this study. Optical and electron microscopy and IR spectroscopy indicated that incident laser fluences of 1-2 J/cm2 at 9.3 and 9.6 micrometers produced sufficient crystalline changes in the carbonated apatite mineral in dentin for caries preventive treatments.

Fried, Daniel S.; Zuerlein, Michael J.; Featherstone, John D.; Machule, Darren

1997-05-01

328

Identificacao de um Modelo de Fonte Composta no Electroencefalograma (Identification of a Composite Source Model on the Electroencephalogram).  

National Technical Information Service (NTIS)

The visual analysis of the electroencephalogram (EEG), discloses several segments with quasi-stationary features, along periods of about 1 to 10 seconds. Some of these, with similar features, may share a common representation (a source). The composite sou...

C. J. C. Teixeira

1988-01-01

329

Analysis of Phase Noise in a J Band Transmitter Analise Do Ruido de Um Transmissor NA Faixa J.  

National Technical Information Service (NTIS)

The phase noise analysis of a frequency generation system using synthesizers and multipliers is described. Rules are shown which can be used in the definition of the system block diagram. An example is presented for a transmitter in band J.

W. J. Fleming

1981-01-01

330

Calibracao de um dosimetro de albedo no ciclotron CV-28. (Calibration of an albedo dosemeter at CV-28 cyclotron).  

National Technical Information Service (NTIS)

This work deals with the analysis and application of neutron measurement techniques in order to obtain information on the neutron spectrum and neutron dose equivalent at several representative working places of the cyclotron laboratory of the Instituto de...

P. W. Fajardo C. L. P. Mauricio

1991-01-01

331

The relationship between English language learning strategies and gender among pre-university students: An overview of UMS  

NASA Astrophysics Data System (ADS)

This study aims to analyze the effects psychological gender differences on the relationship between language learning strategies and their proficiency in English language for pre-university students. Previous researchers found that the more employment of language learning strategies, the more successful the learners are and those with higher level of strategy use are female rather than male. In this study, fifty-six pre-university students (22 males, 34 females) of University Malaysia Sabah participated in this study. Oxford's Strategy Inventory for Language Learning (SILL) self-report questionnaire was adopted to identify the students' language learning strategies, whereas their proficiencies were based on their Malaysian University English Test (MUET) results. Pearson's correlation coefficient, one-way analysis of variance (ANOVA) and the t-test were utilized to make statistical interpretation about the relationship. The knowledge obtained from this study will be helpful for future studies on how to improve the quality of learning and proficiency in English.

Kiram, Johannah Jamalul; Sulaiman, Jumat; Swanto, Suyansah; Din, Wardatul Akmam

2014-06-01

332

ESTABELECENDO PONTES ENTRE O OCIDENTE E O ORIENTE: UM CONTRIBUTO DA PERSPECTIVA BUDISTA NA EDUCAÇÃO PARA A SUSTENTABILIDADE  

Microsoft Academic Search

Dialogue among cultures is a main characteristic on the knowledge construction in the 21st century societies. In this document, following a tradition started around thirty years ago, we try a conversation between western science and eastern Mahayana Buddhist school. The goal of this conversation is to find what contribute this philosophical tradition may give to the development of sustained societies

Orlando Figueiredo; Escola Secundária de Peniche

2006-01-01

333

Invertebrate connectin spans as much as 3.5 um in the giant sarcomeres of crayfish claw muscle  

PubMed Central

In crayfish claw closer muscle, the giant sarcomeres are 8.3 µm long at rest, four times longer than vertebrate striated muscle sarcomeres, and they are extensible up to 13 µm upon stretch. Invertebrate connectin (I-connectin) is an elastic protein which holds the A band at the center of the sarcomere. The entire sequence of crayfish I-connectin was predicted from cDNA sequences of 53 424 bp (17 352 residues; 1960 kDa). Crayfish I-connectin contains two novel 68- and 71-residue repeats, and also two PEVK domains and one kettin region. Kettin is a small isoform of I-connectin. Immunoblot tests using antibody to the 68-residue repeats revealed the presence of I-connectin also in long sarcomeres of insect leg muscle and barnacle ventral muscle. Immunofluorescence microscopy demonstrated that the two repeats, the long spacer and the two PEVK domains contribute to sarcomere extension. These regions rich in charged amino acids, occupying 63% of the crayfish I-connectin molecule, may allow a span of a 3.5 µm distance as a new class of composite spring.

Fukuzawa, Atsushi; Shimamura, Jinen; Takemori, Shigeru; Kanzawa, Nobuyuki; Yamaguchi, Maki; Sun, Peng; Maruyama, Koscak; Kimura, Sumiko

2001-01-01

334

Laser characteristics of a new crystal Nd:Sr5(PO4)3F at 1.328 um  

NASA Astrophysics Data System (ADS)

Nd:Sr5(PO4)3F, known as Nd:S-FAP, is a new material for low-threshold high-efficiency miniature solid- state lasers. By using a tunable due-laser and a xenon flash lamp as well as a laser-diode pump as pump source, respectively, the performance of low-threshold high- efficiency Nd:S-FAP at 1.328 micrometers has been realized. The threshold energy and slope efficiency for different transmission of output reflector were measured. The characteristics of output laser, such as the emission spectrum, the output power, the output energy, the pulse width and so on, were presented.

Zhao, Shengzhi; Wang, Qingpu; Zhang, Xingyu; Wang, Songtao; Zhao, Lu; Sun, Lianke; Zhang, Shaojun

1997-03-01

335

Recuperacao de Imagens Medicas por Conteudo em um Sistema de Gerenciamento de Banco de Dados de Codigo Livre  

Microsoft Academic Search

This paper presents the techniques and the implementation of content-based similarity queries of medical images in an open source database management system, PostgreSQL. The main aspects regarding similarity queries, as image feature extraction and indexing are explained. Empowered with the new features, the development teams working with computer-aided diagnostics systems and medical learning systems can pose similarity queries over images

Humberto Razente; Maria Camila; N. Barioni; Agma J. M. Traina; Caetano Traina Jr

336

UMA PROPOSTA DE UM METAMODELO PARA IMPLEMENTAÇÃO DE SOFTWARE ORIENTADO A OBJETOS ATRAVÉS DA GERAÇÃO AUTOMÁTICA DE CÓDIGO-FONTE  

Microsoft Academic Search

During the development of software one of the most visible risks and perhaps the biggest implementation obstacle relates to the time management. All delivery deadlines software versions must be followed, but it is not always possible, sometimes due to delay in coding. This paper presents a metamodel for software implementation, which will rise to a development tool for automatic generation

Santos Carvalho; Aline Gomes Cordeiro; Marcelo M. Feres

337

A Ferramenta de Análise Estática Klocwork Integrada a um Processo Formal de Revisão de Código, nível 3 do CMMI  

Microsoft Academic Search

This paper describes how the Klocwork tool for static analysis was integrated in the code review process adopted by a CMMI level 3 software development organization. Benefits and quality improvements are presented, such as: (1) improved quality of code reviews, as evidenced by the discovery of a greater number of software defects; (2) reduction of the amount of time required

Denise Piubeli Prado; Aletéia Xavier Bettin; Carlos Miguel Tobar; Vinicius Asta Pagano

338

ESTRUTURA E DINÂMICA DE POPULAÇ?ES ARBÓREAS DE UM FRAGMENTO DE FLORESTA ESTACIONAL SEMIDECIDUAL NA REGIÃO DE PIRACICABA, SP  

Microsoft Academic Search

Tree populations structure and dynamics of a semideciduous seazonal forest fragment in the Piracicaba region, São Paulo state, Brazil Fragmentation of tropical forests associated with anthropogenic disturbance can result in a loss of tree species and floristic composition change throughout the time in a forest fragment. To gather quan- titative data regarding this hypothesis, this study was conducted in a

Henrique E. M. Nascimento

339

In-line charge-trapping characterization of dielectrics for sub-0.5-um CMOS technologies  

NASA Astrophysics Data System (ADS)

The advent of ultra-large and giga-scale-integration (ULSI/GSI) has placed considerable emphasis on the development of new gate oxides and interlevel dielectrics capable of meeting strict performance and reliability requirements. The costs and demands associated with ULSI fabrication have in turn fueled the need for cost-effective, rapid and accurate in-line characterization techniques for evaluating dielectric quality. The use of non-contact surface photovoltage characterization techniques provides cost-effective rapid feedback on dielectric quality, reducing costs through the reutilization of control wafers and the elimination of processing time. This technology has been applied to characterize most of the relevant C-V parameters, including flatband voltage (Vfb), density of interface traps (Dit), mobile charge density (Qm), oxide thickness (Tox), oxide resistivity (pox) and total charge (Qtot) for gate and interlevel (ILO) oxides. A novel method of measuring tunneling voltage by this technique on various gate oxides is discussed. For ILO, PECVD and high density plasma dielectrics, surface voltage maps are also presented. Measurements of near-surface silicon quality are described, including minority carrier generation lifetime, and examples of their application in diagnosing manufacturing problems.

Roy, Pradip K.; Chacon, Carlos M.; Ma, Yi; Horner, G.

1997-09-01

340

Viability of porcine nasal septal cartilage grafts following Nd:YAG (n=1.32um) laser radiation  

NASA Astrophysics Data System (ADS)

Mechanically deformed morphologic cartilage grafts undergo a temperature dependent phase transformation during sustained laser irradiation that results in reshaping of the specimen. While thermal, optical, and mechanical properties of cartilage undergoing laser heating have been previously investigated, the viability of these irradiated grafts has yet to be examined closely until now. In this study, chondrocyte viability following laser irradiation was determined by measuring the incorporation of radiolabelled sulfate (Na 35SO4-2) into proteoglycan (PTG) macromolecules. Proteoglycans are highly sulfated and are the principal molecular constituents of cartilage matrix. Their synthesis directly reflects chondrocyte viability. By measuring the scintillation counts of 35SO4-2 uptake and normalizing the value by the total protein content of each specimen we can determine the level of PTG synthesis rates following laser reshaping. Regional baseline PTG synthesis rates as a function of location was determined by dividing each specimen into six regions. All regions except the most cephalic are demonstrated similar PTG synthesis rates. The most cephalic region exhibited a significantly greater PTG synthesis rates. In order to establish a positive control for this study, specimens were immersed in boiling saline water for approximately 40 minutes. The boiled specimens demonstrated a fivefold increase in normalized radioisotope uptake and suggest that the non-specific uptake of radioactive Na35SO4-2 is caused by structural alterations in the collagen matrix caused by extensive thermal exposure. To avoid this thermal artifact, another positive control was established using nitric oxide was to induce apoptosis of the chondrocytes, resulting in significantly lower PTG synthesis compared to untreated tissue. Cartilage specimens (25 X 10 X 2 mm) were irradiated with light emitted from an Nd:YAG laser (25 W/cm2, (lambda) equals 1.32 micrometer) while radiometric surface temperature, internal stress, and backscattered light were simultaneously recorded. Individual specimens underwent either one, two, or three sequential laser exposures with the duration of each exposure determined in real-time from observation of characteristic changes in integrated backscattered light intensity that correlate with thermal mediated stress relaxation. A five-minute time interval between each irradiation was given to allow the cartilage to return to thermal equilibrium. Average laser exposure for each irradiation sequence was recorded (5, 8.3, 12.2 sec). PTG synthesis decreased with increasing laser exposure, but was noted to remain above baseline levels for NO treated tissue. To further refine these results and minimize the effect of regional tissue variations, 7 mm diameter discs excised from the most cephalic portions and a middle region of the pig nasal septal cartilages were irradiated. A reduction of PTG synthesis rates was noted with each successive irradiation, suggesting that laser mediated cartilage reshaping acutely does not eliminate the population of viable chondrocytes. The degree of reduction in PTG synthesis is dependent upon the time-temperature dependent heating profile created during laser irradiation, and carefully monitored dosimetry is necessary to ensure chondrocyte viability.

Chao, Kenneth K.; Wong, Brian J.; Kim, Hong K.; Milner, Thomas E.; Sung, Chung-Ho; Sobol, Emil N.; Nelson, J. Stuart

2000-06-01

341

AVALIAÇÃO PRELIMINAR DA CORROSÃO SOB TENSÃO DE UM AÇO TIPO ABNT 321 EM AMBIENTE DE REATORES NUCLEARES  

Microsoft Academic Search

Metallic components of nuclear plants undergo synergic effects of mechanical stress, different environments, temperature and materials with the variable histories. As a result the formation of cracks due to the environmental conditions is the more severe way of degradation of metallic components. A cooperation project between Nuclear Technology Development Center\\/Nuclear Energy National Center (CDTN\\/CNEN) and International Atomic Energy Agency has

Mônica Maria de Abreu; Mendonça Schvartzman; Cordeiro Neves; Adalberto Matias; Nelson do Nascimento; Atanazio Filho; Luciana Iglesias Lourenço; Luiz Cláudio Candido

342

Matéria orgânica e propriedades físicas de um Argissolo Amarelo Coeso sob sistemas de manejo com cana-de-açúcar1  

Microsoft Academic Search

The continuous cultivation of the sugar cane for long-term under different management systems in soils of Coastal Tablelands can cause alterations in the organic matter and in the physical properties of the soil. The effects of different management systems with sugar cane on the properties of a Cohesive Yellow Argisol, in the Triunfo Sugar Cane Mill, in the State of

Apolino J. N. da Silva; Mário S. V. Cabeda; Fabíola G. de Carvalho

343

Atributos físicos de um latossolo cultivado com cana-de-açúcar após aplicações de lodo de esgoto e vinhaça  

Microsoft Academic Search

The objective of this work was to evaluate if annual application of sewage sludge and vinasse, residues employed with exclusive purpose of supply N and K to sugar cane, would cause alteration on some physical attributes of clayey Haplustox after the harvests of the 3rd and 4th cuts of the crop. The experiment was carried out in a complete randomized

Fábio Camilotti; Itamar Andrioli; Marcos O. Marques; Alysson R. da Silva; Luiz C. Tasso Júnior; Fabio O. de Nobile

2006-01-01

344

Zona pellucida drilling by a 1.48-um laser: influence on the biomechanics of the hatching process  

Microsoft Academic Search

Efficient and well controlled laser drilling of the zona pellucida of mouse eggs has been demonstrated recently using a 1.48 micrometers laser diode. The zona pellucida openings (5 - 10 micrometers ) can be obtained within the culture dish in an either tangential or more poleward irradiation in respect to the spherical egg structure. Zone drilling is achieved at a

Klaus Rink; Laurent Descloux; Guy P. Delacretaz; Alfred Senn; Dorotha Nocera; Marc Germond

1996-01-01

345

Modeling of 2-um Tm:Ho:ZBLAN diode-pumped cw double-clad fiber lasers  

Microsoft Academic Search

Theoretical modeling of high-power thulium-sensitized holmium fluorozirconate (Tm:Ho:ZBLAN) glass fiber lasers operating on the 2 micrometer transition in holmium is presented. High output power in single-mode can be achieved by pumping the inner cladding of the double clad fiber with a single-mode core with high-power multimode cw diode lasers. The possibility of higher output powers with the double-clad fiber laser

Stuart D. Jackson; Terence A. King

1996-01-01

346

ANÁLISE DE VULNERABILIDADE DE UM PARQUE URBANO ATRAVÉS DE MÓDULOS DE APOIO À DECISÃO EM SISTEMAS DE INFORMAÇÃO GEOGRÁFICA  

Microsoft Academic Search

The urbanization of the Brazilian metropolinan regions produced complex, unequal and compartmented structures. Slopes and green areas were and are not properly used, resulting in environmental degradation and facilitating environmental hazards. The implementation of conservation policies asks for studies and zoning as a way to support the management and monitoring of such areas. The present study develops a vulnerability map

Heinrich Hasenack; Eliseu Weber; Rejane Valdameri

1993-01-01

347

ANÁLISE DAS VULNERABILIDADES DE SEGURANÇA EXISTENTES NAS REDES LOCAIS SEM FIO: UM ESTUDO DE CASO DO PROJETO WLACA  

Microsoft Academic Search

The 802.11x standard for wireless network has been widely adopted by large corporations and institutions during its daily tasks, forasmuch the productivity increase produced by flexibility and mobility found in these new sorts of wireless equipments have provided great operational advantages. Nevertheless, there are some important security issues that should be take in consideration while using this new technology. Having

Lidiane Parente Andrade; Daniel Nelo Soares; Mauro Margalho Coutinho; Antônio Jorge; Gomes Abelém

2003-01-01

348

A participação das mulheres com câncer de mama na escolha do tratamento: um direito a ser conquistado  

Microsoft Academic Search

The purpose of this study was to identify how women with breast cancer perceive themselves as subjects in the process of making decisions on their own treatment. Two objectives were pursued: (a) to identify social and political determinants that, by affecting the socialization process of these women, might have influenced them in adopting a style of participation, and (b) to

Sandra Lucia Arantes; Marli Villela Mamede

2003-01-01

349

Critical issues for developing a high-throughput SCALPEL system for sub-0.18-um lithography generations  

NASA Astrophysics Data System (ADS)

The potential for SCALPEL to provide economically viable production lithography capabilities for post-optical generations depends largely on achieving adequate wafer throughput. We have analyzed throughput-limiting performance attributes of the SCALPEL approach in order to identify critical design issues and develop a process for evaluating its unique parameter space. An important feature of the SCALPEL approach is that small image sub-fields are assembled to form complete device patterns. Further, electron-electron interactions result in a throughput- dependent image blur, which is a governing parameter for many inter-related performance areas of SCALPEL. Error budgets for key issues affecting critical dimension (CD) have been developed to analyze this unique design space, using models of the image-forming process including stitching on sub-field seams. These budgets assist in identifying the most critical design issues and demonstrating their inter-relationships and tradeoffs.

Stanton, Stuart T.; Liddle, James A.; Waskiewicz, Warren K.; Mkrtchyan, Masis M.; Novembre, Anthony E.; Harriott, Lloyd R.

1998-06-01

350

UM ESTUDO DOS EFEITOS DE ALTERAÇÕES DO PREÇO DA NAFTA NA FORMAÇÃO DE PREÇOS DA CADEIA PETROQUÍMICA  

Microsoft Academic Search

Abstract: Input price volatility creates pressures for price adjustments, interfering in contracts between buyer and sales in petrochemical chain. One of the remarkable results pointed out by Fan (1998) is the role of price instability and uncertainty in the levels of vertical integration of the industry. This paper deals with the role of raw material price formula, basically nafta prices

José Maria F. J. da Silveira; Emerson Fernandes Marçal

2006-01-01

351

Measurement of optical absorptance according to ISO 11551: parallel round-robin test at 10.6 um  

NASA Astrophysics Data System (ADS)

For an elaborate assessment of the laser-calorimetric standard practice described in the International Standard ISO 11551 'Test methods for absorptance of optical laser components' an extended international round-robin test has been performed. In contrast to a former experiment with a serial concept, in the present parallel test identical commercial sample sets have been sent to the partners after an initial measurement of absorptance at the coordinator, where the experiment was completed by a final inspection and second screening measurement of absorptance. The result of the round-robin test are compared and evaluated on the basis of standard evaluation techniques and alternative statistical methods. With the exception of a few deviations, which can be attributed to specific properties of the individual measurement systems, a good agreement of the absorption values was observed.

Ristau, Detlev; Willamowski, Uwe; Welling, H.

1999-04-01

352

Degenerate four-wave mixing spectrum of C60 between 0.74 and 1.7 um  

Microsoft Academic Search

We have extended the wavelength range of our previous study of the third order nonlinear optical susceptibility tensor (chi) (3)(-(omega) , (omega) , (omega) , -(omega) ) of a thin C60 film to 1.7 micrometers . We use time-resolved degenerate four-wave-mixing with femtosecond pulses to measure both the phase and magnitude of (chi) 1111. Our data are well defined in

Friedrich P. Strohkendl; Theresa J. Axenson; Larry R. Dalton; Robert W. Hellwarth; H. W. Sarkas; Zakya H. Kafafi

1996-01-01

353

Wind velocity, water vapor, and temperature measurements from space using 2 um Tm:Ho;YAG laser  

NASA Astrophysics Data System (ADS)

In meteorological and climatological fields, the scientific community will increasingly need global measurements of key atmospheric parameters with high spatial resolution (horizontal as well as vertical): the spaceborne lidars are the most suitable instruments for those missions. While backscatter lidar (ATLID, currently studied as ESA) is presently first candidate for space deployment, the next generation of lidars will be DIAL and Doppler wind lidars, presenting a higher level of complexity, mainly due to the large power and complex signal processing required. The present considered wind lidars are based on CO(subscript 2) lasers, whose space compliance still needs confirmation, while alexandrite lasers are considered for water vapor and temperature measurements, but they need flashlamp pumping which poses a lot of several thermal constraints and lifetime problems: on the other side, the recent developments achieved in solid-state technology allow to envisage diode pumping as most promising possibility for both previous applications.

Ghibaudo, Jean-Bernard; Krawczyk, Rodolphe; Armandillo, Errico; Faucheux, Marc A.; Benedetti-Michelangeli, G.; Hettlage, E.; Flamant, Pierre H.; Pelon, Jacques R.; Fantoni, Roberta; Salvetti, G.; Fiocco, G.; Luthy, Willy

1994-09-01

354

Identification of the Mechanisms Underlying Antiestrogen Resistance: Breast Cancer Research Partnership between FIU-UM Braman Family Breast Cancer Institute.  

National Technical Information Service (NTIS)

We have completed all proposed training and research project tasks. This research proposal had two primary objectives which were to (1) increase FIU investigators research expertise and competitive ability to succeed as independent breast cancer researche...

D. Roy

2012-01-01

355

Thermal cycling reliability of Cu\\/SnAg double-bump flip-chip assemblies for 100um pitch applications  

Microsoft Academic Search

Thick Cu column based double-bump flip-chip structure is one of the promising alternatives for fine pitch flip-chip applications. In this study, the thermal cycling (T\\/C) reliability of Cu\\/SnAg double-bump flip-chip assemblies was mainly investigated and the failure mechanism was analyzed through the correlation of T\\/C test results and the finite element analysis (FEA). T\\/C failures occurred from the outmost Cu\\/SnAg

Ho-Young Son; Il-Ho Kim; Soon-Bok Lee; Gi-Jo Jung; Byung-Jin Park; Kyung-Wook Paik

2007-01-01

356

Estudo espectral em raios-X duros de fontes do tipo Z com o HEXTE/RXTE  

NASA Astrophysics Data System (ADS)

Apresentam-se os resultados de um estudo espectral em raios-X de fontes do tipo Z. As fontes do tipo Z são binárias de raios-X de baixa massa (BXBM) com campo magnético intermediário (B~109G). Esta classe de fontes é composta por apenas 6 fontes Galácticas (a saber: ScoX-1, 9, 7, CygX-2, 5 e 0). A nossa análise se concentra na faixa de raios-X duros (E ~ 20keV), até cerca de 200keV, faixa ótima de operação do telescópio "High Energy X-ray Timing Experiment" (HEXTE), um dos três telescópios de raios-X à bordo do Rossi X-ray Timing Explorer (RXTE). Nossa motivação para tal estudo, uma busca de caudas em raios-X duros em fontes do tipo Z, foi o pouco conhecimento sobre a emissão nesta faixa de energia das referidas fontes quando comparadas, por exemplo, as fontes do tipo atoll (também BXBM). Apresentam-se a análise/redução de dados e explicita-se a maneira como o HEXTE mede o ru1do de fundo. Especial atenção é direcionada a este item devido a localização das fontes do tipo Z e também ao problema de contaminação por fontes próximas. Com exceção de ScoX-1, nenhuma cauda em raios-X duros foi encontrada para as outras fontes, a despeito de resultados de detecção dessas caudas em algumas fontes pelo satélite BeppoSAX. As interpretações deste resultado serão apresentadas. Do ponto de vista deste estudo, nós deduzimos que a produção de caudas de raios-X duros em fontes do tipo Z é um processo disparado quando, pelo menos, uma condição é satisfeita: o brilho da componente térmica do espectro precisa estar acima de um certo valor limiar de ~4´1036ergs-1.

D'Amico, F.; Heindl, W. A.; Rothschild, R. E.

2003-08-01

358

Los Hispanos: Problemas y Oportunidades. Resumen de la Actual Situacion Demografica, Economica, Social y Politica de los Hispanos en los Estados Unidos y de las Iniciativas Tomadas por la Fundacion Ford Para Hacer Frente a las Necesidades de esta Poblacion en Aumento y Determinar sus Efectos Sobre la Sociedad Estadounidense. Documento de Trabajo de la Fundacion Ford, No. 436.  

ERIC Educational Resources Information Center

The Hispanic population's growing impact on American society has caused the Ford Foundation to explore new Foundation initiatives. The 1980 census revealed 14.6 million Hispanics: 60% Mexican American; 14% Puerto Rican; 6% Cuban, and 20% Other. The Hispanic population in the United States is growing and is characterized by diversity; rapid growth…

Ford Foundation, New York, NY.

359

Modelo de Petrov-Galerkin combinado com esquemas auto-adaptativos e sua aplicacao na resolucao numerica de problemas com camada limite. (Combined Petrov-Galerkin method with auto-adapting schemes and its applications in numerical resolution of problems with limit layer).  

National Technical Information Service (NTIS)

In this paper a new finite element model is constructed combining an r- refinement scheme with the CCAU method. The new formulation gives better approximation for boundary and internal layers compared to the standard CCAU, without increasing computer code...

R. S. Silva A. C. Galeao E. G. D. Carmo

1989-01-01

360

Metodo espectro-nodal para solucao das equacoes Sn em geometria x,y para problemas de penetracao profunda em meios altamente absorventes. (Spectral nodal method for the solution of the Sn equations in x,y geometry for highly absorbing deep penetration problems).  

National Technical Information Service (NTIS)

Presented here is an attempt to improve the accuracy of transport nodal methods applied to deep penetration transport problems in x, y-geometry. The resulting nodal method uses the Spectral Green's Function (SGF) scheme for solving the one-dimensional tra...

R. C. Barros

1991-01-01

361

La regulación de los órganos de gobierno de las cajas de ahorros: consideraciones electorales  

Microsoft Academic Search

El presente trabajo supone un avance en la resolución de los problemas de elección social y reparto proporcional de las cajas de ahorros españolas. La regulación estatal y regional relativa a estas instituciones no resuelve adecuadamente los problemas en las elecciones a representantes a los órganos rectores de dichas entidades financieras. La elección de un método para un problema de

Santiago Carbó Valverde; Antonio Palomares Bautista; Victoriano Ramírez González

2004-01-01

362

1.2-um GaInAs/GaAs lasers: are they useful for high-capacity single-mode fiber datacom?  

NASA Astrophysics Data System (ADS)

Gigabit/s-LANs with 0.85 micrometers vertical cavity surface emitting lasers (VCSELs) are now going into the market. But, their link length is limited to be shorter than 500 m due to modal dispersion of employed multi-mode fibers and various modal problems should be considered in system design. The next step will be to develop long wavelength VCSELs matching to a single model fiber with longer link lengths of several km and higher data rates. Long wavelength single mode fiber datacom should be advantageous because of avoiding modal noise and relaxing eye safe issues. Recently, we demonstrated a 1.2 micrometers wavelength highly strained GaInAs/GaAs quantum well edge emitting laser, which exhibits reasonably low threshold and excellent temperature characteristics. The threshold current is as low as 13 mA for an as-cleaved 5 X 380 micrometers laser. A characteristic temperature T0 under pulsed operating is as high as 140 K. This is the record high T0 in 1.2-1.3 micrometers wavelength band. Even under 'heatsink-free' cw operations, T0 was much higher than that of conventional 1.3 micrometers GaInAsP/InP systems. We can avoid thermoelectric coolers as well as heatsink itself, thus, an all-plastic mold package without heatsink may give us a drastic cost reduction. It is interesting to note than commercial standard single mode fibers are designed to locate a cut-off wavelength at around 1.2 micrometers for the purpose of production tolerance. A question arises: whether this 1.2 micrometers wavelength band can be utilized for single mode fiber datacom or not.We have demonstrated a 2 Gb/s-5km single mode fiber data transmission experiment using a fabricated 1.22 micrometers uncooled GaInAs/GaAs laser. We believe that the VCSEL technology may drastically improve the transmitter performances at this new wavelength band and this 1.2 micrometers Gigabit LAN may become realistic by extensive developments. In this paper, we would like to discuss a possibility of high speed datacom using a newly developed 1.2 micrometers highly strained GaInAs/GaAs lasers.

Koyama, Fumio; Schlenker, Dieter; Miyamoto, Tomoyuki; Chen, Zibiao; Iga, Kenichi

1999-11-01

363

1.2-um GaInAs\\/GaAs lasers: are they useful for high-capacity single-mode fiber datacom?  

Microsoft Academic Search

Gigabit\\/s-LANs with 0.85 micrometers vertical cavity surface emitting lasers (VCSELs) are now going into the market. But, their link length is limited to be shorter than 500 m due to modal dispersion of employed multi-mode fibers and various modal problems should be considered in system design. The next step will be to develop long wavelength VCSELs matching to a single

Fumio Koyama; Dieter Schlenker; Tomoyuki Miyamoto; Zibiao Chen; Kenichi Iga

1999-01-01

364

Sy m posi um-i n-Pri nt : P hotoreceptors Evolutionary Patterns of Retinal-Binding Pockets of Type I Rhodopsins and Their Functionst  

Microsoft Academic Search

Genome sequencing projects resulted in the identification of a large number of new sequence homologs of archaeal rhodopsins in marine bacteria, fungi, and unicellular algae. It is an important task to unambiguously predict the functions of these new rhodopsins, as it is difficult to perform individual experiments on every newly discovered sequence. The trans- membrane segments of rhodopsins have similar

Larisa Adamian; Zheng Ouyang; Yan Yuan Tseng; Jie Liang

365

Equilíbrio e coordenação motora em pré-escolares: um estudo comparativo Balance and motor coordination in pre-school: a comparative study  

Microsoft Academic Search

The neuromotor development is a very complex mechanism. Understanding a small child development process means to be aware of its behavior changes, either psychomotor, emotion or cognitive. The objective of this study is to better understand these problems and to propose solutions that will respond to the needs of the children. We analyzed pre- school children regarding their static and

Maria Fátima de Sousa Bess; João Santos Pereira

366

QUALIDADE AMBIENTAL (?) EM ÁREAS DE EXPANSÃO URBANA: UM ESTUDO DE CASO SOBRE A PERDA DA COBERTURA VEGETAL DO BAIRRO PARQUE VERDE - BELÉM\\/PA  

Microsoft Academic Search

O crescimento acelerado das cidades acarretou sérios prejuízos à qualidade ambiental das áreas de expansão urbana, pois a ocupação urbana desordenada configurada nestes espaços substituiu de forma degradante o espaço natural transformando-o em espaço construído sem qualquer planejamento urbano que levasse em conta a vegetação como componente essencial da qualidade de vida humana. Dentro deste contexto, o bairro Parque Verde,

CIÊNCIA EDUCAÇÃO; SUELLEN CRISTINA; VIDAL COSTA; NÍVIA BERNA DA SILVEIRA CORRÊA

367

Aplicacao do metodo da variancia efetiva na calibracao de um monitor de contaminacao. (Application of effective variance method for contamination monitor calibration).  

National Technical Information Service (NTIS)

In this report, the calibration of a thin window Geiger-Muller type monitor for alpha superficial contamination is presented. The calibration curve is obtained by the method of the least-squares fitting with effective variance. The method and the approach...

O. L. Goncalez I. S. M. Freitas

1990-01-01

368

Cost Effective Implementation of a 90 V RESURF P-type Drain Extended MOS in a 0.35 um Based Smart Power Technology  

Microsoft Academic Search

This paper describes a 90 V, 300 m?. mm2 RESURF P-type drain extended MOS (PDEMOS) transistor in a 0.35 µm based smart power technology. The excellent performance of the device is realised with a dedicated Pdrift layer, designed to achieve maxi- mum benefit from the RESURF effect. The proposed ap- proach is very cost effective since there is only one

B. Bakeroot; M. Vermandel; P. Moens; J. Doutreloigne; D. Bolognesi

2002-01-01

369

Sintetizador de Frequencia Digital Directo para um Sistema de Espalhamento de Espectro por Salto em Frequencia (Direct Digital Frequency Synthesiser for Frequency Hopping Spread Spectrum).  

National Technical Information Service (NTIS)

The thesis has a complete study of a direct digital frequency synthesizer, DDFS, for application on frequency hopping spread spectrum systems. The study is developed in three parts: theoretical, software simulation, and hardware implementation. In the the...

F. A. B. Cercas

1988-01-01

370

Prospects for large-format IR astronomy FPAs using MBE-grown HgCdTe detectors with cutoff wavelength > 4 um  

Microsoft Academic Search

Rockwell Science Center has developed a double layer planar heterostructure (DLPH) detector array fabrication process with significant advantages over the PACE-1 process now being used to produce 256 X 256 and 1024 X 1024 FPAs for low background IR astronomy. The DLPH detectors are p- on-n photodiodes fabricated in a double layer of wide and narrow bandgap HgCdTe grown by

Robert B. Bailey; Jose M. Arias; William V. McLevige; John G. Pasko; Annie C. Chen; Craig Cabelli; Lester J. Kozlowski; Kadri Vural; Jian Wu; William J. Forrest; Judith L. Pipher

1998-01-01

371

A Method for Calculating Bidimensional Fourier-Bessel Transformation Functions Um Metodo Para Calculo DOS Coeficientes DA Transformada de Fourier-Bessel Bidimensional.  

National Technical Information Service (NTIS)

The Gauss quadrature method is extended for the two dimensional case with restriction of the abcissas in order to obtain coefficients for Fourier-Bessel series expansion. A table of zeros for the Bessel functions is included.

J. A. G. Pereira L. G. M. Filho

1978-01-01

372

Distribuicao de Densidade E Potencial Electrostatic Em Torno de Um Satelite Cilindrico (Density and Electrostatic Potential Distribution around a Cylindrical Satellite).  

National Technical Information Service (NTIS)

The electrostatic potential distribution around a cylindrical satellite, moving with a constant speed, is presented. Magnetic field effects are neglected. The method of characteristics for solving quasi-linear partial differential equations is employed to...

H. U. Pilchowski I. Mdemoraes

1986-01-01

373

Aplicação do Método de Monte Carlo, GEANT 4 e SRIM 2003 no Projeto de um Tomógrafo por Feixe Prótons de Baixa Energia  

Microsoft Academic Search

Resumo - A radioterapia por feixe de prótons é uma alternativa altamente eficiente no tratamento do câncer. Atualmente, nos centros de tratamento por prótons, o cálculo de dose é baseada em imagens de tomografia computadorizadas de raio-x (CT) e o paciente é posicionado com auxílio de radiografias de raio-x. A alternativa proposta é a utilização da tomografia por feixe de

J. A. P. Setti; E. Milhoretto; S. R. Junior; H. R. Schelin; M. C. L. Klock; V. Denyak; R. Rocha; I. Evseev; O. Yevseyeva

374

Raman shifting in the absence of multiple Stokes orders with a 1.3-um Nd:YAG laser in hydrogen  

NASA Astrophysics Data System (ADS)

A Q-switched Nd:YAG laser generating 160 mJ in 60 ns at 1.3 micrometers has been shifted to 2.9 micrometers by Raman conversion in hydrogen. The energy of the 2.9 micrometers photons is insufficient to undergo further Stokes shifts. Thus the first Stokes line is the terminal wavelength for this process. While terminal Stokes components have been reached in previous Raman shifting studies, these components have always been the result of multiple Stokes shifts. In a single pass configuration photon conversion of up to 0.37 was realized. Conversion into anti-Stokes lines of up to third order was observed, albeit at insignificant energies. With the addition of an unoptimized resonator the photon conversion rose to 0.49. The pressure dependence of Stokes conversion was also investigated. The data show a smooth increase in output followed by saturation. This is in accordance with conversion into a single terminal Stokes lines. However, in contradiction with theory, the pump linewidth was observed to matter a great deal. Amplified elastic or near elastic scattering is suggested as an explanation for this result. Overall, the success of this work bodes well for forthcoming attempts to obtain tunable mid-IR radiation by means of a terminal first Stokes shift.

Watson, Jason P.; Miller, Harold C.

1996-05-01

375

Hyper-numerical aperture (NA = 2.8) microscope using ? = 1.56 um femtosecond source for multi-photon imaging  

PubMed Central

A new microscope is discussed, where the scanning illumination has a numerical aperture of 2.8 with ? = 1.56 µm femtosecond fiber laser. Samples are placed or grown on a silicon substrate. Multi-photon emission is imaged in transmission on a cooled CCD. Two-photon and three-photon effects are observed from the silicon/water interface and gold nanoparticles. Images of cells, reference spheres and gold nanoparticles illustrate imaging properties of the microscope. Spectral characteristics of individual particles are achieved with a blazed transmission grating. Emission properties of differently sized gold nanoparticles are studied in detail, which indicate that their emission is a two-photon effect due continuum generation. Interestingly, spectral shape and emission power are similar for 20nm, 40nm and 60nm diameter gold nanoparticles for the cases studied.

Kim, Youngsik; Lu, Phat; Milster, Tom D.; Kieu, Khanh

2013-01-01

376

Microwave Oscillator Stabilized by a Dielectric Resonator at 5.4 Ghz Oscilador de Microondas Estabilizado for Um Ressoador Dieletrico Em 5,4 Ghz.  

National Technical Information Service (NTIS)

A dielectric resonator stabilized oscillator at 5.43 GHz is described. The dielectric resonator, magnetically coupled to a microstrip line, is the principal element of the tuning network connected to the input port of a feedback transistor. With this proc...

P. M. Marshall C. E. Santana

1982-01-01

377

Procaoc: Um Programa Para Calculo, Analise E Optimizacao de Circuitos Em Microondas (Procaoc: A Program for Computation, Analysis and Optimization of Circuits).  

National Technical Information Service (NTIS)

A computer program for analysis and optimization of active and passive linear circuits composed by one, two, three and four port devices belonging to the library of elements internally defined is described. The statistical and sensitivity analysis of the ...

C. M. Dasilva

1984-01-01

378

Viabilidade de Inclusao de um Tratamento Enzimatico no 'Adocamento' de Farinhas de 'Lupinus Sp.' (Evaluation of Enzymatic Preparations in the Debittering of Lupine Seed Flours).  

National Technical Information Service (NTIS)

The soundness of including an enzymatic pre-treatment in the debittering of Lupine seeds was investigated. For this purpose an initial series of trials was performed in order to select the best range of sizes for the lupine seed particles. This was perfor...

F. M. C. Santana

1990-01-01

379

Prolegomenos a um estudo da lingua brasileira nos terreiros de origem africana (Prolegomena to a Study of the Brazilian Language of the Voodoo Rites of African Origin).  

ERIC Educational Resources Information Center

Determination of the authenticity of lexical items with Sub-Saharan origin in the voodoo rites of candomble and umbanda in Brazil requires establishing a socio-historical basis for the African diaspora and the current configuration of terreiros. The terreiros demonstrate varying linguistic repertoires according to their affiliation with candomble…

Megenney, William W.

380

Thulium:YAG VapoEnucleation of the prostate in large glands: a prospective comparison using 70- and 120-W 2-um lasers  

PubMed Central

This study compared the efficacy of 70- and 120-w 2-µm thulium:YAG VapoEnucleation of the prostate (ThuVEP) for patients with benign prostatic obstruction (BPO). A prospective analysis of 84 patients with symptomatic BPO and prostatic enlargement (?60 ml) who underwent either 70-w (n=44) or 120-w ThuVEP (n=40) non-randomly was carried out. Patient demographics and perioperative and 12-month follow-up data were analysed. The mean prostate volume was 79.90±27.49 ml in patients who had received 70-w ThuVEP, which was less than in those who had received 120-w ThuVEP (88.53±25.10; P=0.033). The mean enucleation (resected weight/laser time, 2.16±1.21 g min?1 vs. 1.23±0.60 g min?1; P=0.013), operation efficiency (resected weight/total operation time, 0.76±0.35 g min?1 vs. 0.42±0.27 g min?1; P=0.000) and percentage of resected tissue (66.93%±22.79% vs. 45.41%±23.33% P=0.000) were higher with 120-w treatment compared to 70-w ThuVEP. One patient (1.2% of total patients) (in the 120-w group) required a blood transfusion postoperatively. Sixty-one patients (73%) were available for review at the 12-month follow-up time point. The quality of life (QoL), International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), postvoiding residual urine (PVR) and prostate volume improved significantly after treatment (P?0.035) and were not significantly different between those treated with the different devices (70- and 120-w). The median prostate volume reduction was 81.70% and 82.19% with 70- and 120-w ThuVEP, respectively. The incidence of complications was low and did not differ between groups treated with the different devices. Two patients (2.4%) (one per group) had a bladder neck contracture at the follow-up. ThuVEP is a safe and efficacious procedure for the treatment of symptomatic BPO. The incidence of complications was low with both devices. The 120-w thulium:YAG device enhances the effectiveness of ThuVEP with regard to the percentage of resected tissue and the enucleation/operation efficiency.

Netsch, Christopher; Bach, Thorsten; Herrmann, Thomas RW; Gross, Andreas J

2012-01-01

381

Detecao, Aquisicao e Demodulacao de Sinais em um Sistema de Comunicacao Comacesso Aleatorio (Detection, Acquisition and Signal Demodulation in a Communication System with Random Access).  

National Technical Information Service (NTIS)

The development of a signal processor for the Data Collecting System of the first Brazilian Complete Space Mission is presented. The signals from the data collecting platforms are random both in time and frequency, and are spread over a band of 24 kHz. Th...

L. C. Pacolasobrinho

1988-01-01

382

Tissue welding for corneal wound suture with a CW 1.9-um diode laser: an in-vivo preliminary study  

NASA Astrophysics Data System (ADS)

This study aimed to evaluate the interest of a 1.9 micrometer diode laser for corneal wound suture. Six adult albino rabbits were anesthetized. A 7 mm corneal incision was practiced on the right eye. For 3 animals (laser plus stitch) the incision was surgically sutured with 2 stitches of a nylon monofilament and laser impacts were performed between the stitches. For 3 animals (laser only) juxtaposed lasers impacts were realized to suture the wound. After the procedure the animals were examined daily for signs of inflammation, infection and for healing of the corneal wound. Material was obtained for histological examination 1 month after the procedure. Approximation of the edges of the would was successfully obtained in the (laser plus stitch) group. In the (laser only) group this approximation remained troublesome. After the procedure, one cornea of the (laser only) group disclosed a little leakage during 2 days. Histological examination assessed the welding of the corneal wound in the two groups provided structural modifications and some inflammatory signs. Corneal welding using a 1.9 micrometer diode laser is possible either with laser and stitch or with laser only. The approximation of the edges of the wound with additional stitches is an evident drawback. The use of additional stitches should be avoided to keep the theoretical advantages of corneal would suture using laser welding.

Desmettre, Thomas; Mordon, Serge R.; Mitchell, Valerie A.

1996-01-01

383

Portable on-ground hard- and software system for obtaining and processing spectrally spreaded images in the ranges of 3-5 and 8-14 um  

NASA Astrophysics Data System (ADS)

The use of thermovision systems for the remote sensing of surface temperatures has been conventional for a long time. In recent years serious progress has been achieved in the reduction of instrumental errors of IR receivers and increase of quality of thermal images visualization and registration. The smaller progress is observed in questions of reduction of methodical measuring errors, in a sense of the determination by thermovision methods of the true (thermodynamic) temperature of a radiating surface, its factor of radiation, and the determination of a ratio of own and reflected radiation. It is expected that the essential progress can be achieved by creation of thermovision systems, carrying out registration of objects in several spectral subranges of ranges 3-5 or 8-14 micrometer. A similar result can be achieved by use of single-channel devices with a set of spectral filters. Such an approach provides, in essence, the registration of multispectral thermal images, further mathematical processing of which (or processing in a real time scale), permits us to make approaches to solving the above mentioned problems. Thus, the problem of determination of a spectrum of radiation for each point of the image on the basis of results of multispectral measurements becomes the central one. As a criterion the most optimum accuracy and complete time of measurement (for single-channel systems) or amount of channels (for multichannel systems) should be used. Naturally, the term 'accuracy' must be determined. The offered technique was being created during scientific cooperation between the Institute of Radio-electronics of the Russian Academy of Sciences (IRE RAN), producing thermovision systems, and the State Research Institute of Aviation Systems (GosNIIAS) which makes software for such devices and realizes the multispectral processing.

Medvedev, Evgeny M.; Falkov, Edward J.; Kartzev, Alexander V.; Scherbakov, Michael I.

1995-12-01

384

Efeito tópico de iodo-povidona 0,5% comparado com natamicina 5% em ceratites fúngicas causadas por Fusarium solani em um modelo animal de coelhos: estudo piloto  

Microsoft Academic Search

Purpose: To evaluate the efficacy of topical administration of 0.5% povidone-iodine in experimental Fusarium solani keratitis in rabbits. Methods: Fungal keratitis caused by Fusarium solani was induced in the right eye of 24 New Zealand rabbits. The rabbits were randomly divided into 3 different treatment groups: Group I (povidone-iodine) - treated with topical 0.5% povidone-iodine; Group II (natamycin) - treated

Lauro Augusto de Oliveira; Thales Takeo Takata; Olga Fischman Gompertz; Luciene Barbosa de Sous; Mark J. Mannis

385

Determination of optimum laser parameters for cartilage reshaping in porcine septum using Nd:YAG laser (lambda=1.32 um)  

NASA Astrophysics Data System (ADS)

In this study, a computer-controlled instrument was designed and constructed in order to systematically evaluate the effect of laser dosimetry on shape change during laser- mediated cartilage reshaping. Porcine nasal septal cartilage specimens, stripped of periocondrium were cut (25 x 5 x 2 mm) using a custom guillotine microtome and bent into a cylindrical shape (7.38 mm bend radius) using a jig constructed from aluminium tubing and high tension wire. Each specimen was irradiated (Nd:YAG laser (lambda) = 1.32 micrometers , 6-10 W, 2-16 s pulse duration, 31-51 W/cm2) in five distinct regions using a pattern that maximized cooling between laser exposures. Real-time measurements of tissue optical properties and surface temperatures were recorded during each laser exposure as these features correlate with the onset of stress relaxation and shape change. After irradiation, each specimen was re-hydrated in saline solution (15 minutes), removed from the jig, and photographed with a digital camera. The radius of curvature of the specimen was compared to the radius (7.38 mm) of the reshaping jig. Optimal reshaping (greatest degree of curvature) was observed at 6W, with an irradiation time of 16s, or alternately at 10W, with an irradiation time of 8s.

Johansen, Elizabeth; Burden, Matt A.; Wong, Brian J.

2001-07-01

386

Habilidades sociais das mães e envolvimento com os filhos: um estudo correlacional Mothers' social skills and their involvement with children: a correlacional study  

Microsoft Academic Search

This study aimed to identify and to analyze the mother's social skills repertoire and their involvement with their children. Twenty-two mothers, whose children were in the first grade, participated in this study. They completed the Mother's Evaluation of Family Interaction Quality questionnaire and Social Skills Inventory (IHS-Del-Prette). The participants reported good social skills repertoire , which was positively correlated to

Fabiana CIA; Camila de Sousa; Zilda Aparecida; Pereira DEL PRETTE; Almir DEL PRETTE

387

Comparison of Spitzer/IRAC Galactic Center 3.6-8.0 ?um survey results with X-ray emission in the central 40 × 40 parsecs  

NASA Astrophysics Data System (ADS)

We have studied the correlation between 2357 Chandra X-ray point sources identified by Muno et al. (2003) in a 40 × 40 parsec field and ~20,000 infrared sources we observed in the corresponding subset of our 2 × 1.5 degree Spitzer/IRAC Galactic Center Survey at 3.6-8.0 ?m (see Stolovy et al.; this conference), using various spatial and brightness thresholds. The correlation was determined for source separations of less than 0.5, 1.0 or 2.0 arcsec. No significant correlation was found between the X-ray and infrared point sources on these scales. Only one compact infrared source, IRS 13, can be identiffed with any of the dozen prominent X-ray emission features in the 3 × 3 parsec region centered on Sgr A*, and the diffuse X-ray and infrared emission around Sgr A* seems to be anti-correlated on a few-arcsecond scale. We compare our results with previous identifications of near infrared companions to Chandra X-ray sources.

Gezari, D. Y.; Arendt, R. G.; Smith, R.; Stolovy, S.; Yusef-Zadeh, F.; Law, C.; Smith, H. A.; Moseley, H.; Ramirez, S.; Karr, J.; Cotera, A.; Sellgren, K.

2006-12-01

388

750 mW, 1.06 um, CW TEM00 output from a Nd:YVO4 laser end pumped by a single 20 stripe diode array  

Microsoft Academic Search

We report the highest electrical to optical conversion efficiency (12.5%), and the highest cw output power (750 mW), from any solid state laser crystal end pumped by a single multiple stripe diode laser array. The optical slope efficiency, which refers to the 1.06 mum output power divided by the optical pump power incident on the end face of our laser

R. A. Fields; M. Birnbaum; C. L. Fincher; J. Berger; D. F. Welch; D. R. Scifres; W. Streifer

1988-01-01

389

Um Estudo das Funcoes de Similaridade DA Camada Limite Planetaria. Parte 2: Resultados (Study of the Functions of Similarity of the Planetary Boundary Layer. Part 2. Results).  

National Technical Information Service (NTIS)

Micrometeorological data obtained during atmospheric boundary layer testing over tropical savannah land in Koorin, Australia are used to evaluate similarity functions A, B, and C of the planetary boundary layer. Different flux-profile relationships are ev...

J. C. S. Chagas Y. Viswanadham

1984-01-01

390

Um Estudo das Funcoes de Similaridade DA Camada Limite Planetaria. Parte 1: Teoria (Study of the Functions of Similarity of the Planetary Boundary Layer. Part 1. Theory).  

National Technical Information Service (NTIS)

The concept of asymptotic similarity is extended to the planetary boundary layer. Similarity functions A, B, and C of the planetary boundary layer are discussed using Rossby-number similarity theory. Simplified theoretical expressions of functions A, B, a...

Y. Viswanadham J. C. S. Chagas

1984-01-01

391

SISTEMAS DE COLHEITA DA CANA-DE-AÇÚCAR E ALTERAÇÕES NAS PROPRIEDADES FÍSICAS DE UM SOLO PODZÓLICO AMARELO NO ESTADO DO ESPÍRITO SANTO1  

Microsoft Academic Search

A long term (1989-1994) experiment with sugar cane (RB 739735) was carried out, in Linhares, ES, Brazil, in order to evaluate the effect of two systems of sugar cane harvesting: the first with previous burning (burned cane), and the second with crop residue remaining on the soil surface (green cane), on some physical properties of a tableland Yellow Podzolic soil.

MARCOS BACIS CEDDIA; LÚCIA HELENA CUNHA; DOS ANJOS; EDUARDO LIMA; ALEXANDRE RAVELLI NETO

392

Diode-laser-pumped 1.065-um Nd:Sr5(VO4)3F laser and its intracavity frequency doubling  

NASA Astrophysics Data System (ADS)

Nd:Sr5(VO4)3F, known as Nd:S-VAP, is a new material for efficient and miniature diode-pumped solid state lasers. By using a laser-diode pump operating at 809 nm, Nd:S-VAP is successfully lased at 1.065 micrometers . A slope efficiency of 43.5% and a laser threshold of only 11 mW are measured. The theoretical formulas for threshold power and slope efficiency are written and the theoretical calculations are in agreement with the experimental results. In addition, by using KTP as an intracavity-doubling crystal, the intracavity frequency of the Nd:S-VAP laser at 0.5325 micrometers is also realized. The threshold power is 13.2 mW and the TEM00 mode green laser output power is 25.6 mW at 200 mW incident pump power, corresponding to an optical efficiency of 12.8%. In addition a way to improve efficiency is discussed.

Zhao, Shengzhi; Wang, Qingpu; Zhang, Xingyu; Wang, Songtao; Zhao, Lu; Sun, Lianke; Zhang, Shaojun

1996-12-01

393

Efficient first-overtone CO laser as a potential source of IR radiation (y=2.5 to 4.2 um) for frequency-selective laser ablation  

Microsoft Academic Search

An overview of theoretical and experimental results on first-overtone (FO) CO laser obtained for the period of approximately 20 years is presented. A special attention is paid to the quite new results jointly obtained at the Lebedev Physics Institute (Russia), TRINITI (Russia) and Air Force Research Lab (USA). Efficient multiwavelength pulsed FO CO lasing with output efficiency up to 11%

Andrei A. Ionin

2000-01-01

394

A fauna de Rotallida (Foraminiferida) da borda do recife de Itacimirim, Bahia, Brasil: um estudo comparativo do sedimento e das algas como substrato  

Microsoft Academic Search

This study aimed to compare the Rotaliida fauna (Foraminiferida) that lives in the sediment with that attached on algae from the Itacimirim's reef border, Bahia's north coast. Six samples of sediment and six of algae were collected in sites distributed along the reef border. The first 200 foraminnifers of each sample were selected, identified and the specimens belonging to the

Yonara S. Braga; Altair J. Machado; Simone S. Moraes

2008-01-01

395

Effect of hydrogen concentration in conventional and IAD coatings on the absorption and laser-induced damage at 10.6 um  

NASA Astrophysics Data System (ADS)

In this paper, data of single layers of YbF3, BaF2, YF3, and NaF and multilayer coatings produced by conventional thermal evaporation (boat, e-beam) and ion assisted deposition (IAD) are compared. Hydrogen concentration depth profiling was performed using nuclear reaction analysis based on the reaction 1H(15N, (alpha) (gamma) )12C. Absorption was measured with the aid of a laser calorimeter and a cw CO2 laser. A computer-controlled test facility with a TEA CO2 laser was used for determining the 1-on-1 damage thresholds of the coatings. The results point out that the absorption and damage behavior of coatings for the CO2 laser wavelength are related to the total amount of species containing hydrogen. Most of the IAD coatings exhibit a lower hydrogen contamination than conventional thin films.

Rahe, Manfred; Ristau, Detlev; Schmidt, Holger

1993-06-01

396

Crystal-free and low-flow-angle ILD by using in situ SACVD/PE BPSG for 0.5-um application  

NASA Astrophysics Data System (ADS)

As the technology pushes down to half-micron or below, a low flow angle BPSG film for pre- metal dielectric (PMD) becomes necessary. With high BP concentration BPSG, for example 4 X 6, low flow angle can be achieved after proper reflow. The drawback is that, frequently, BPSG crystal appears at smaller poly spacing. The combined sub-atmosphere chemical vapor deposition (SACVD) and BPSG films through in-situ deposition in applied materials P-5000D system was implemented to not only improve reflow angle but also suppress the crystal formation at any poly space. A crystal-free with 11 degree(s) flow angle PMD was achieved by using 4KA SACVD and 5KA BPSG over 6000A poly lines. A detailed SACVD/BPSG process and the comparison of BPSG reflow characterization with and without SACVD are presented.

Yen, Hung-Chi; Jin, Ben-Yih; Wong, Cliff; Chow, Peter; Yen, Daniel; Hu, Joseph; Su, Joe S.; Wang, Jean

1994-09-01

397

Crystal-free and low-flow-angle ILD by using in situ SACVD\\/PE BPSG for 0.5-um application  

Microsoft Academic Search

As the technology pushes down to half-micron or below, a low flow angle BPSG film for pre- metal dielectric (PMD) becomes necessary. With high BP concentration BPSG, for example 4 X 6, low flow angle can be achieved after proper reflow. The drawback is that, frequently, BPSG crystal appears at smaller poly spacing. The combined sub-atmosphere chemical vapor deposition (SACVD)

Hung-Chi Yen; Ben-Yih Jin; Cliff Wong; Peter Chow; Daniel Yen; Joseph Hu; Joe S. Su; Jean Wang

1994-01-01

398

Cannabidiol: from an inactive cannabinoid to a drug with wide spectrum of action Canabidiol: de um canabinóide inativo a uma droga com amplo espectro de ação  

Microsoft Academic Search

Objective: The aim of this review is to describe the historical development of research on cannabidiol. Method: This review was carried out on reports drawn from Medline, Web of Science and SciELO. Discussion: After the elucidation of the chemical structure of cannabidiol in 1963, the initial studies showed that cannabidiol was unable to mimic the effects of Cannabis. In the

Antonio Waldo Zuardi

2008-01-01

399

Scalable counter architecture for a pre-loadable 1 GHz@0.6 um\\/5V pre-scaler in TSPC  

Microsoft Academic Search

In this paper we describe an approach for using the true single phase clock (TSPC) circuit style for the implementation of a scalable, pre-loadable pre-scaler. By utilization of a signed digit (SD) based redundant adder cell the execution of the necessary addition operation can be performed in only one clock cycle, independent of the length of the applied operators. The

Aizdreas Wassatsch; Dirk Timmermann

2001-01-01

400

A música como experiência e diferencial mercadológico no turismo: um estudo de caso sobre o trecho Serro a São Gonçalo do Rio Preto - Estrada Real - MG  

Microsoft Academic Search

The search for places, which provide meaningful and unique experiences, is increasing in the tourism activity, and consequently, it is necessary to change the marketing strategy in places and attractions. The musical expression of Minas Gerais is not promoted as cultural contrast, although it is a great tourist attraction. This article suggests the use of the experimental marketing and the

Mariana Helena; Diniz Ferreira; Mileno Dias Marquezini

401

High-precision measurements of CO2 concentration in air by means of diode-laser absorption spectroscopy near 2 um  

Microsoft Academic Search

12 A compact and portable laser-based sensor has been developed for absolute measurements of CO2 concentration with high precision and accuracy, in air samples at atmospheric pressure. a DFB diode laser, operating near 2 micrometers at room temperature, was used. It was tuned into resonance with the R(34) line of the v1 + 2v2 degree(s) + v3 combination band. The

R. Restieri; Gianluca Gagliardi; G. De Biasio; F. Cotrufo; Livio Gianfrani

2001-01-01

402

Obtencao de parametros dinamicos de um reator nuclear atraves da tecnica de malha adaptativa. (Obtainment of nuclear power plant dynamic parameters by adaptive mesh technique).  

National Technical Information Service (NTIS)

This thesis involves the problem in determination of the parameters of the Mathematical Model of a Nuclear Reactor, including non-linearity which is considered as a bi-linear system. Being a non-linear model, the determination of its parameters cannot be ...

W. Carvalho Miranda

1979-01-01

403

Síndrome pré-menstrual em adolescentes: um estudo transversal dos fatores biopsicossociais Premenstrual syndrome in adolescents: a transversal study of the bio-psycho-social factors  

Microsoft Academic Search

Objective: To evaluate the prevalence and to identify aspects related to the Premenstrual Syndrome (PMS) in adolescents of private high school (Fundação Santo An- dré, Santo André - SP). Methods: Transversal study line, carried through with 360 students, ages varying from 14 to 18 years old. The evaluation had two phases. Phase one: standard protocol application to identify youths with

Maria Regina Domingues de Azevedo; Maria Ignez Saito; Eliezer Berenstein; Drauzio Viegas

404

Imbe ddi ng AIED i n i e TV through Broadband Use r Mode l l i ng (BbUM)  

Microsoft Academic Search

Earlier this year we were asked to offer an AIED perspective to the development of interactive educational television (ie-TV). This theme paper discusses our response to the question: what can the field of AIED offer to developers of education for the wired and wireless future with particular respect to TV? We note the changes that have taken place over the

ROSEMARY LUCKIN; BENEDICT DU BOULAY

405

Confusion about a little observatory: the history of the first high school observatory (German Title: Verwirrung um eine kleine Sternwarte: Die Geschichte der ersten Chemnitzer Schulsternwarte )  

NASA Astrophysics Data System (ADS)

By means of a small watercolor, painted by a musicologist, the existence of the highschool observatory of Chemnitz was rediscovered. The small observatory was build in 1893 by means of funds and a donation: after WW I it was also used for popular education. During Nazi times, the observatory fell into neglect, and the mechanical damage made it impossible to put it back into operation after WW II The building was torn down in 1964 and forgotten.

Pfitzner, Elvira

406

Temperature distributions in Nd:YAG (lambda=1.32 um) laser-irradiated cartilage grafts accompanied by cryogen spray cooling  

NASA Astrophysics Data System (ADS)

Laser irradiation of mechanically deformed cartilage results in permanent shape change. Under optimal conditions, the cartilage graft must be rapidly heated to the critical transition temperature, required for reshaping, while maintaining a spatially uniform temperature distribution. These two conditions are not easily satisfied, as increasing irradiance results in larger temperature gradients between irradiated and non-irradiated surfaces. Moreover, such a gradient increases with cartilage thickness. Inasmuch as uncontrolled heating of the irradiated surface may result in overt chondrocyte death, the temperature in cartilage must be monitored and controlled. We propose feedback-controlled cryogen spray cooling as a technique to allow rapid laser heating within the cartilage while protecting the irradiated surface. In this investigation, we measured radiometric surface temperatures on irradiated and non-irradiated surfaces of porcine septal cartilage specimens (thickness 1.5, 2.0, 2.5 and 3 mm) during Nd:YAG laser exposure ((lambda) equals 1.32 micrometer, 50 pulse repetition rate, 5 - 50 W/cm2) with and without cryogen spray cooling. Along with surface temperatures, back-scattered light from an amplitude-modulated HeNe probe laser ((lambda) equals 632.8, 10 mW) was collected by a fiber and detected with a silicon photoreceiver using a lock-in amplifier. Previously, we have demonstrated that an increase followed by a sharp decline in the back-scattered light intensity signal correlates closely with characteristic alterations in cartilage thermal and mechanical properties accompanying the reshaping process, which suggest the occurrence of a phase transformation. The difference between irradiated and non-irradiated radiometric surface temperatures was determined as a function of time and related to incident laser irradiance and specimen thickness. To minimize excessive heating and produce a more uniform temperature distribution, a cryogen (10 ms) spurt was delivered at the surface coincident with the area of laser irradiation. The cryogen spurt was triggered whenever the radiometric surface temperature on the irradiated surface reached 50 degrees Celsius. Back-scattered HeNe light was noted to increase, peak, and subsequently decrease during sustained laser irradiation in the presence and absence of cryogen spray cooling (CSC). Laser irradiation was terminated after the peak in the back-scattered HeNe signal was observed on the lock-in amplifier. The critical transition radiometric surface temperature increased with laser irradiance. In the absence of CSC, temperatures on irradiated and non-irradiated surfaces of a 1.5 mm section of cartilage differed by 1.5, 7, and 10 degrees Celsius for 5, 15, and 30 W/cm2, respectively, at the peak in light scattering. During laser irradiation with CSC, the radiometric surface temperature on the irradiated surface varied between 25 - 50 degrees Celsius. Radiometric surface temperatures on the non-irradiated surface did not exceed 70 degrees Celsius. A peak in the light scattering curve was still consistently observed for CSC irradiated tissue and was noted to occur when the non-irradiated surface temperature reached 45 degrees Celsius. The use of CSC during laser irradiation permits rapid and homogeneous heating within the cartilage while potentially protecting the irradiated surface.

Karamzadeh, Amir M.; Wong, Brian J.; Milner, Thomas E.; Dao, Xavier; Tanenbaum, B. Samuel; Nelson, J. S.

1999-06-01

407

Clinical application of a new 0.63- to 0.65-um pulse diode laser in treating ear, throat, and nose diseases in adults and children  

NASA Astrophysics Data System (ADS)

An investigation was made of applying a pulsed diode laser emitting at the wavelengths of 0.63 to 0.65 micrometers to treat various otolaryngological diseases, such as rhinosinusitis, acute rhinitis, vasomotor rhinitis, allergic rhinitis, the illness of the lymphoid ring, adenoiditis, chronic tonsillitis, pharyngitis, and catarrhal and suppurative otitis. The therapeutic effect produced by the pulsed diode laser was compared with that of conventional therapeutic lasers. It was found that the pulsed low-intensity laser radiation in the red spectrum region offered a number of advantages over conventional laser therapeutic techniques.

Nasedkin, Alexy N.; Pletnev, A. S.

2001-04-01

408

BIBGTR: um conjunto de bibliotecas de dados nucleares para os codigos Usimug e Anisn. (BIBGTR: nuclear data libraries for the programs Unimug and Anisn).  

National Technical Information Service (NTIS)

Nuclear data libraries generable by the NJOY for the programs UNIMUG and ANISN, using evaluated data from ENDF/B-IV and ENDF/B-V are described. These libraries will be used by Radioisotope Thermoelectric Generators Project of Instituto de Estudos Avancado...

S. Ono A. D. Caldeira

1989-01-01

409

Efeitos de um programa de orientação de atividade física e nutricional sobre o nível de atividade física de mulheres fisicamente ativas de 50 a 72 anos de idade  

Microsoft Academic Search

Effects of an intervention program of physical activity and nutrition orientation on the physical activity level of physical- ly active women aged 50 to 72 years old The promotion of a physically active lifestyle in elderly people has been used as a strategy to promote improvement in health standards and quality of life. The objective of this study was to

Marcela Ferreira; Sandra Matsudo; Victor Matsudo; Glaucia Braggion

2005-01-01

410

Cryogenic bidirectional reflectance distribution function (BRDF) measurements at 10.6 um on contaminated mirrors for the Midcourse Space Experiment (MSX) satellite program  

Microsoft Academic Search

Effects of contaminants on optical surfaces is a continuing concern for space-based systems-- especially those containing cryogenic optical systems. Effects of contaminant films on mirror bidirectional reflectance distribution function (BRDF) were studied in support of the Midcourse Space Experiment (MSX) Satellite that is scheduled for launch in 1994. This study present experimental results of infrared scattering measurements made on cryogenic

Bryan L. Seiber; Robert J. Bryson; Bobby E. Wood

1994-01-01

411

The Application of Remote Sensors to a Model for Fish Mapping O Sensoriamento Remoto Aplicado a Um Modelo de Cartas de Pesca.  

National Technical Information Service (NTIS)

A methodology for the determination of the best potential fishing zones, for sardines, in the Brazilian coastal area of the southwestern tropical Atlantic Ocean, between latitudes 21 deg 45'S and 25 deg 00'S and longitudes 40 deg 50'W and 47 deg 00'W is p...

S. Maluf

1978-01-01

412

Continuous Flow Atmospheric Pressure Laser Desorption/Ionization Using a 6-7-um-Band Mid-Infrared Tunable Laser for Biomolecular Mass Spectrometry  

PubMed Central

A continuous flow atmospheric pressure laser desorption/ionization technique using a porous stainless steel probe and a 6–7-µm-band mid-infrared tunable laser was developed. This ion source is capable of direct ionization from a continuous flow with a high temporal stability. The 6–7-µm wavelength region corresponds to the characteristic absorption bands of various molecular vibration modes, including O–H, C=O, CH3 and C–N bonds. Consequently, many organic compounds and solvents, including water, have characteristic absorption peaks in this region. This ion source requires no additional matrix, and utilizes water or acetonitrile as the solvent matrix at several absorption peak wavelengths (6.05 and 7.27 µm, respectively). The distribution of multiply-charged peptide ions is extremely sensitive to the temperature of the heated capillary, which is the inlet of the mass spectrometer. This ionization technique has potential for the interface of liquid chromatography/mass spectrometry (LC/MS).

Hiraguchi, Ryuji; Hazama, Hisanao; Senoo, Kenichirou; Yahata, Yukinori; Masuda, Katsuyoshi; Awazu, Kunio

2014-01-01

413

Distribuicao do tempo para contagem de amostras em um detetor de radiacao. (Distribution of time for counting samples in radioactivity counter).  

National Technical Information Service (NTIS)

The precision and the sensibility of measures of activity, made by a radioactivity counter, improve as function of counting time. The precision also increases as the measured activities do. This work describes an auxiliary method for division of time avai...

D. Azevedo Py Junior

1990-01-01

414

Effects of resist strip processing damage on the electrical characteristics of 0.8-um a-Si antifuse circuit elements  

NASA Astrophysics Data System (ADS)

Field-programmable ASICs have been implemented using a variety of programmable circuit elements, including SRAM, EPROM, E2PROM, and antifuse cells. Amorphous silicon (a-Si) antifuse cells offer greater packing densities and superior performance compared to cells based on memory elements, and they can be integrated into conventional multi-layer integrated circuits with the addition of several process modules. Despite their advantages, a potential yield issue with a-Si antifuses is that their electrical characteristics can be affected by damage from manufacturing processes. In this study, it is found that the programming voltage is reduced when a solvent-based post-resist strip solution is applied to the bottom electrode layer of TiW. Atomic-force microscopy (AFM) shows that the resist strip solution increases the micro-roughness of TiW films. It is also found that the `off-'state leakage current increases when the solution is applied to the a-Si antifuse layer. The amount of the leakage current increase is related to the amount of a-Si loss due to the strip solution.

Fujishiro, Felix; Vines, Landon B.; Ravindhran, K. S.; Han, Yu-Pin; Echtle, Danny; Garcia, Annette; Richardson, Brian; Weling, Milind; Hickey, James; Loh, Ying-Tsong

1994-09-01

415

Modelacao Matematica de um Forno de Vidro: Aplicacao a Optimizacao do Processo (Mathematical Modelling of a Glass Melting Furnace Application Process Optimization).  

National Technical Information Service (NTIS)

The complex interactions between the several phenomena occuring in the several parts of a furnace entails the appearance of numerical procedures able to predict a whole furnace (combustion chamber batch and glass tank) by an integrated way. A three-dimens...

M. A. de Barros da Silva Nogueira

1991-01-01

416

Dynamic changes in the elastic modulus of lagomorph nasal septal cartilage during Nd:YAG (lambda = 1.32 um) laser irradiation  

NASA Astrophysics Data System (ADS)

The elastic modulus of rabbit nasal septal cartilage was measured during Nd:YAG laser ((lambda) = 1.32 micrometers , 10 seconds, 21.22 W/cm2) radiation. Cyclical force versus displacement curves were generated in cantilevered specimens (9.5 mm x 3.0 mm x 1.0 mm) using a calibrated thin beam load cell and a single axis motorized micropositioner (velocity = 0.3 mm/sec). The laser and a thermopile were positioned above the secured specimen. Samples were irradiated three times with 30 second cooling intervals between each sequential laser exposure. Surface temperature reached a maximum of 65 degree(s)C. Measurements were recorded before, during, and after each laser irradiation, and then following complete rehydration in normal saline (NS) for 1 hour at 25 degree(s)C. Following each laser exposure, the sample was sprayed with normal saline delivered via an atomizer to prevent desiccation. Elastic modulus was calculated using a model assuming linear elastic behavior. The modulus in native tissue was 6.08 +/- 0.17 Mpa, and this decreased during and after each successive laser exposure (5.41 +/- 0.39 Mpa, 4.94 +/- 0.46), (5.05 +/- 0.104 Mpa, 4.17 +/- 0.46 Mpa), (4.23 +/- 0.53, 3.71 +/- 0.60 Mpa), for the first, second, and third laser exposures, respectively. Following rehydration for one hour in normal saline, the modulus returned to near-baseline values (5.33 +/- 0.40 Mpa). The results suggest that molecular changes that occur in the cartilage tissue matrix during laser cartilage reshaping are not accompanied by irreversible changes in the matrix modules.

Chao, Kenneth K.; Burden, Matt A.; Wong, Brian J.

2001-07-01

417

Stress Relaxation of Porcine Septal Cartilage During Nd:YAG (A=1.32 um) Laser Irradiation: Mechanical, Optical and Thermal Responses  

NASA Astrophysics Data System (ADS)

Laser-assisted cartilage reshaping is mediated by thermally induced stress relaxation, and may be used to alter cartilage morphology for reconstructive surgical procedures in the upper airway and face without carving, morselizing, and suturing. Internal stress (sigma) (t), integrated backscattered light intensity I(t) from a He-Ne probe laser ((lambda) equals 632.8 nm), and radiometric surface temperature Sc(t) were measured during the reshaping of porcine nasal septal cartilage using a pulsed Nd:YAG laser ((lambda) equals 1.32 micrometers ). Internal stress and integrated backscattered light intensity were observed to increase, plateau, and then decrease in similar ways during laser irradiation. The plateau region occurred when the cartilage front surface temperature approached 65 degree(s)C. I(t) was utilized in a feedback control procedure to reshape cartilage specimens from a flat to a curved geometry. Immediately following laser irradiation, the tissues were rehydrated in normal saline for 15 min while wrapped around a small dowel. A stable shape change was retained for 21 days while the specimens were stored in normal saline at 5 degree(s)C. The backscattered light intensity signal mirrors underlying changes in internal stress, and further rate of change or slope of I(t) is nearly zero when the surface temperature reaches about 65 degree(s)C. Measurements of I(t) (or, equivalently, the fractional change in integrated backscattered light intensity (Delta) I(t)/I0) may be used to control the process of laser-assisted cartilage reshaping and minimize nonspecific thermal injury due to uncontrolled heating.

Wong, Brian J.; Milner, Thomas E.; Kim, Hong H.; Nelson, J. S.; Sobol, Emil N.

1998-10-01

418

Mobicalc: Um Sistema Integrado E Interativo Para Desenvolvimento de Modelos Administrativos (Mobicalc: An Integrated and Interactive System for Development of Administrative Models).  

National Technical Information Service (NTIS)

The development of a programming system based on the concept of a electronic spreadsheet is presented. The developed system offers the basis for the development of a programming environment scheme based on Logic programming. This scheme is presented.

E. T. Yano

1987-01-01

419

Construcao de um sistema de bobinas magneticas de 13 kG. (Construction of a 13 kG magnetic coil system).  

National Technical Information Service (NTIS)

The construction of magnetic coil system for a 35 GHz gyrotron is reported in great detail. This system is designed to generate a magnetic induction of 13,2 kG over an extension of 13 cm. By using an operating current of about 100 A, it was verified that ...

J. O. Rossi Y. Aso P. J. Castro J. J. Barroso G. O. Ludwig

1991-01-01

420

Construcao de um girotron de 35 GHz e de 100 kW. (Construction of a 35 GHz 100 kW gyrotron).  

National Technical Information Service (NTIS)

In this work a description of a 35 GHz 100 kW gyrocon is described which is under construction at the National Space Research Institute Plasma Laboratory. Project conceptual aspects are emphasized, specifically high current density thermionic cathodes, hi...

Y. Aso J. J. Barroso P. J. Castro R. A. Correa G. O. Ludwing

1989-01-01

421

Caracterização do microhabitat e vulnerabilidade de cinco espécies de arapaçus (Aves: Dendrocolaptidae) em um fragmento florestal do norte do estado do Paraná, sul do Brasil  

Microsoft Academic Search

Microhabitat characterization and vulnerability of five woodcreeper (Dendrocolaptidae) species in a forest fragment in northern state of Paraná, southern Brazil. Little information is available on the ecological requirements of the woodcreepers (Aves: Dendrocolaptidae), and on the causes of their tendency to disappear from forest fragments in the Neotropics. Here, we documented microhabitat selection of five syntopic species of woodcreepers in

Fabíola Poletto; Luiz dos Anjos; Edson Varga Lopes; Graziele Hernandes Volpato

2004-01-01

422

512- and 1024-element linear InGaAs detector arrays for near-infrared (1-3um) environmental sensing  

NASA Astrophysics Data System (ADS)

512 and 1024 elements linear In(subscript x)Ga(subscript 1-x)As detector arrays have been fabricated for cutoff wavelengths of 1.7 micrometers (x equals 0.53, E(subscript g) equals 0.73 eV), 2.2 micrometers (x equals 0.71, E(subscript g) equals 0.56 eV), and 2.6 micrometers (x equals 0.82, E(subscript g) equals 0.47 eV) using hydride vapor phase epitaxy (VPE) and metallorganic chemical vapor deposition (MOCVD). The 25 X 500 micrometers s pixel sizes have a center to center spacing of 25 micrometers and currently exhibit typical leakage currents of 6 pA (300 K, -10 mV) for 1.7 micrometers cutoff arrays, 500 pA (300 K, -10 mV) for 2.2 micrometers cutoff arrays, and 20 nA (300 K, -10 mV) for 2.6 micrometers cutoff arrays. Improved crystal growth, n-type sulfur doping (-1 X 10(superscript 17) cm(superscript -3)) of the semiconductor 'cap' layer and the active InGaAs layer, and post-crystal growth thermal cyclings of the detector wafers have helped to reduce the leakage current in these detectors. Furthermore, these techniques have produced a remarkable increase in the photodetector yields, which is essential for the commercial viability of these arrays. The relationship between the photodetector bandgap (E(subscript g)) and the theoretically lowest attainable leakage current is discussed. The design of a new infrared (IR) multiplexer operating at near zero bias is also discussed.

Joshi, Abhay M.; Ban, Vladimir S.; Mason, S. M.; Kazakia, M.; Kosonocky, Walter F.

1992-12-01

423

Cryogenic beam-combiner for very low background 2- to 20-um interferometry on the 22.8-m Large Binocular Telescope  

NASA Astrophysics Data System (ADS)

The 22.8 m Large Binocular Telescope Interferometer will be a uniquely powerful tool for imaging and nulling interferometry at thermal infrared wavelengths (2 - 20 micrometers ) because of the LBT's unusual combination of low emissivity, high spatial resolution, broad (u,v)-plane coverage, and high photometric sensitivity. The gregorian adaptive secondary mirrors permit beam combination after only three warm reflections. They also control the relative pathlength, wavefront tip/tilt, and focus of the two telescope beams, thus greatly simplifying the complexity of the beam-combiner. The resulting four-mirror beam-combiner reimages the original focal plane and also images the telescope pupil onto a cold stop to limit thermal background. At first-light in 2004, an all-reflective, cooled beam-combiner can provide a 2 arcmin diameter field for Fizeau-style imaging as well as the low thermal background and achromaticity required for nulling interferometry.

McCarthy, Donald W.; Sabatke, Erin M.; Sarlot, Roland J.; Hinz, Philip M.; Burge, James H.

2000-07-01

424

O POTENCIAL DE IMAGENS QUICKBIRD PARA ANÁLISE DO RELEVO DE UM SETOR DO PLANALTO DAS ARAUCÁRIAS, RS: CENTRO DE PESQUISAS E CONSERVAÇÃO DA NATUREZA PRÓ-MATA  

Microsoft Academic Search

This paper analyzes the potential of high-resolution images (QuickBird satellite) to mapping the relief features of a sector of the Planalto das Araucárias, an elevated area in northeastern Rio Grande do Sul, State, Brazil. The Center for Research and Nature Conservation PRÓ-MATA was chooses as an experimental area. In 1994, the PRÓ-MATA was created to perform studies and to propose

Eduardo da Silva Pinheiro; Hermann Johann; Heinrich Kux; Jorge Alberto Villwock

425

RESÍDUOS DAS INDÚSTRIAS MADEIREIRAS: UM ESTUDO DE CASO NAS SERRARIAS DE RIO BRANCO - ACRE 1 Lumber Industry Residues: A Case Study of Rio Branco-Acre Sawmills  

Microsoft Academic Search

Resumo: Este estudo aborda o setor madeireiro no município de Rio Branco-Acre. Os objetivos gerais foram levantar e discutir informações sobre os resí duos gerados nas serrarias de Rio Branco, especificamente naqueles localizadas no distrito industrial, com o intuito de subsidiar o planejamento das serrarias quanto ao gerenciamento dos resíduos. Neste contexto, o estudo visou, de forma específica: 1) a

Suelem Marina de Araújo; Rosana Cavalcante dos Santos

426

Heavy-ion broad-beam and microprobe studies of single-event upsets in 0.20 um SiGe heterojunction bipolar transistors and circuits.  

SciTech Connect

Combining broad-beam circuit level single-event upset (SEU) response with heavy ion microprobe charge collection measurements on single silicon-germanium heterojunction bipolar transistors improves understanding of the charge collection mechanisms responsible for SEU response of digital SiGe HBT technology. This new understanding of the SEU mechanisms shows that the right rectangular parallele-piped model for the sensitive volume is not applicable to this technology. A new first-order physical model is proposed and calibrated with moderate success.

Fritz, Karl (Mayo Foundation, Rochester, MN); Irwin, Timothy J. (Jackson & Tull Chartered Engineers, Washington, DC); Niu, Guofu (Auburn University, Auburn, AL); Fodness, Bryan (SGT, Inc., Greenbelt, MD); Carts, Martin A. (Raytheon ITSS, Greenbelt, MD); Marshall, Paul W. (Brookneal, VA); Reed, Robert A. (NASA/GSFC, Greenbelt, MD); Gilbert, Barry (Mayo Foundation, Rochester, MN); Randall, Barbara (Mayo Foundation, Rochester, MN); Prairie, Jason (Mayo Foundation, Rochester, MN); Riggs, Pam (Mayo Foundation, Rochester, MN); Pickel, James C. (PR& T, Inc., Fallbrook, CA); LaBel, Kenneth (NASA/GSFC, Greenbelt, MD); Cressler, John D. (Georgia Institute of Technology, Atlanta, GA); Krithivasan, Ramkumar (Georgia Institute of Technology, Atlanta, GA); Dodd, Paul Emerson; Vizkelethy, Gyorgy

2003-09-01

427

Flexible delivery of Er:YAG radiation at 2.94 um with negative curvature silica glass fibers: a new solution for minimally invasive surgical procedures  

PubMed Central

We present the delivery of high energy microsecond pulses through a hollow-core negative-curvature fiber at 2.94 µm. The energy densities delivered far exceed those required for biological tissue manipulation and are of the order of 2300 J/cm2. Tissue ablation was demonstrated on hard and soft tissue in dry and aqueous conditions with no detrimental effects to the fiber or catastrophic damage to the end facets. The energy is guided in a well confined single mode allowing for a small and controllable focused spot delivered flexibly to the point of operation. Hence, a mechanically and chemically robust alternative to the existing Er:YAG delivery systems is proposed which paves the way for new routes for minimally invasive surgical laser procedures.

Urich, A.; Maier, R. R. J.; Yu, Fei; Knight, J. C.; Hand, D. P.; Shephard, J. D.

2012-01-01

428

GERENCIAMENTO POR PROCESSO: UM ESTUDO DE CASO NO SETOR SUCROALCOOLEIRO BRASILEIRO PROCESS MANAGEMENT: A CASE STUDY OF THE BRAZILIAN SUGAR ALCOHOL SECTOR  

Microsoft Academic Search

Resumo: O objetivo deste trabalho é analisar os resultados da mudança na estrutura funcional de uma empresa sucroalcooleira, realizada por uma empresa de consultoria especializada em gestão empresarial. Assim, para a realização deste trabalho foi usado o método de estudo de caso único, baseado em relatórios de consultoria. Os principais resultados encontrados foram: (1) o retorno financeiro devido à mudança

Ricardo Alexandre Feliciano; Roberto Gilioli Rotondaro

429

Os partidos trabalhistas no sistema multipartidário: um estudo comparado das trajetórias do PTB (1945-1964) e do PT (1980-2002)  

Microsoft Academic Search

The article discusses the trajectories of Brazilian Labour Parties, comparing the movement, in the ideological spectrum, of PTB (Brazilian Labour Party, between 1945 and 1964) and PT (Workers Party, between 1980 and 2002). We argue that the parties' ideological positions are set by their goals and the strategies they adopt to implement these goals. The nature of the goals depends

Geralda Luiza de Miranda

430

Resultados Do Projeto Gondwana: Um Exemplo de Correlacao Geologica Intercontinental Utilizando Imagens Landsat (Results of the Gondwana Project: An Example of Intercontinental Geologic Correlation Utilizing Landsat Imagery).  

National Technical Information Service (NTIS)

The main results in INPE's GONDWANA Project are presented. The project focus was on a geological comparison between Northeast Brazil and West Africa using LANDSAT and RADAR imageries. It is shown that Northeast Brazil and West Africa in the Late Proterozo...

R. Pereiradacunha, P. R. Martini, E. Crepani

1989-01-01

431

Hydatidosis cases in one of Mar del Plata City hospitals, Buenos Aires, Argentina Casos de hidatidose em um hospital da Cidade de Mar del Plata, Buenos Aires, Argentina  

Microsoft Academic Search

Hydatidosis is a zoonosis of worldwide distribution produced mainly by the metacestode Echinococcus granulosus. In Argentina, its distribution reaches endemic levels. The aims of this investigation were to contribute to the knowledge of hydatidosis in the southeast of Buenos Aires province, study its evolution at the Interzonal General Hospital for Acute Diseases between 1992 and 2002 and discuss its importance.

Marcela Cecilia Dopchiz; María Celina Elissondo; María Alejandra Rossin; Guillermo Denegri

2007-01-01

432

Aerogamaespectrometria e aeromagnetometria de um trato ocidental do Pre-Cambriano Paulista. (Aerial gamma spectrometry and aerial magnetometry of the occidental tract from Paulista Precambrian).  

National Technical Information Service (NTIS)

This work includes processing and interpretation of airborne spectrometric and magnetometric data of a 20.000 km(sup 2) area between the cities of Sao Paulo and Pirassununga (Sao Paulo State, Brazil). Spectrometric maps were produced and interpreted, show...

F. J. F. Ferreira

1991-01-01

433

Energia solar fotovoltaica: Contributo para um roadmapping do seu desenvolvimento tecnológico [Fotovoltaic solar energy: a contribute to a technological development roadmapping  

Microsoft Academic Search

The main goal for this report is to alert for the need of a continuous investment in policies that should be developed worldwide, with respect to research and development (R&D), at all levels, in photovoltaic energy. The R&D in this area leads to a strong and possible solution to the actual environmental problems. Such problems are based on the climate

Hugo Gil Silva; Marcos Afonso

2009-01-01

434

Increased efficiency of silicon light-emitting diodes in a standard 1.2-um silicon complementary metal oxide semiconductor technology  

NASA Astrophysics Data System (ADS)

Scaled versions of a variety of silicon light-emitting diode elements (Si LEDs) have been realized using a standard 1.2- micrometers , double-polysilicon, double-metal, n-well CMOS fabrication process. The devices operated with a n+p junction biased in the avalanche breakdown mode and were realized by using standard features of the ORBIT FORESIGHT design rules. The elements emit optical radiation in a broad band in the 450- to 850-nm range. An emitted intensity of up to 7.1 (mu) W/cm2 has been obtained with 5 mA of current at an operating voltage of 18.5 V. Excellent uniformity in emission intensity of better than 1 percent variation was obtained over areas as large as 100 X 500 micrometers . A best power conversion efficiency of 8.7 X 10-8 and a quantum efficiency of 7.8 X 10-7 were measured. All of these values are about one order of magnitude better than previously reported values for Si LED avalanche devices. Coupling between the elements as well as electro- optical coupling between an element and an optical fiber was realized.

Snyman, Lukas W.; Aharoni, Herzl; du Plessis, Monuko; Gouws, Rudolph B.

1998-07-01

435

A emissão em 8mm e as bandas de Merrill-Sanford em estrelas carbonadas  

NASA Astrophysics Data System (ADS)

Estrelas carbonadas possuem bandas moleculares em absorção no visível e, no infravermelho (IR) as principais características espectrais se devem a emissão de grãos. Recentemente foi detectada a presença de bandas de SiC2 (Merrill-Sanford, MS) em emissão sendo atribuída à presença de um disco rico em poeira. Neste trabalho analisamos uma amostra de 14 estrelas carbonadas, observadas no telescópio de 1.52 m do ESO em 4 regiões espectrais diferentes, a fim de detectar as bandas de MS em emissão. Nossa amostra é composta de estrelas que apresentam além da emissão em 11.3 mm, outra em 8 mm. Esta última emissão, não usual nestes objetos, tem sido atribuída ou a moléculas de C2H2, ou a um composto sólido ainda indefinido. A detecção de emissões de MS e aquelas no IR, simultaneamente, revelaria um cenário mais complexo que o habitualmente esperado para os ventos destes objetos. No entanto como primeiro resultado, verificamos que as bandas de Merrill-Sanford encontram-se em absorção, não revelando nenhuma conexão com a emissão a 8 mm. Assim, temos duas hipóteses: (a) a emissão a 8 mm se deve à molécula C2H2 ou (b) essa emissão é resultado da emissão térmica de grãos. Testamos a segunda hipótese modelando a amostra com grãos não-homogêneos de SiC e quartzo, o qual emite em aproximadamente 8mm. Este grão seria produzido em uma fase evolutiva anterior a das carbonadas (estrelas S) e por terem uma estrutura cristalina são destruídos apenas na presença de campos de radiação ultravioleta muito intensos. Os modelos para os envoltórios utilizam o método de Monte Carlo para descrever o problema do transporte da radiação. As conclusões deste trabalho são: (1) as bandas de Merrill-Sanford se encontram em absorção, sugerindo um cenário usual para os ventos das estrelas da amostra; (2) neste cenário, a emissão em 8 mm seria resultado de grãos de quartzo com mantos de SiC, indicando que o quartzo poderia sobreviver a fase evolutiva S.

de Mello, A. B.; Lorenz-Martins, S.

2003-08-01

436

Projeto do sistema anti-ressonante da fiação dos transdutores para o detector Mario Schenberg  

NASA Astrophysics Data System (ADS)

O detector de ondas gravitacionais Mario Schenberg está sendo projetado e construído pelo grupo Gráviton. Sua construção está ocorrendo no Laboratório de Estado Sólido e Baixas Temperaturas (LESBT) da Universidade de São Paulo, na cidade de São Paulo. Esse detector possui uma massa ressonante esférica de cobre-alumínio, com 65 cm de diâmetro, pesando aproximadamente 1150 Kg, suspensa por um sistema de isolamento vibracional, que se encontra em fase de testes preliminares. A real eficácia desse sistema, entretanto, só poderá ser comprovada quando o detector estiver aparelhado com, pelo menos, um transdutor eletromecânico de altíssima sensibilidade acoplado à massa ressonante. Neste momento, não só este sistema de isolamento vibracional será posto em teste, como o do projeto da fiação que transporta os sinais de microondas até os transdutores e destes para a pré-amplificação. Apesar dessa fiação ter sido projetada para não apresentar nenhum contato com a superfície esférica da antena, de maneira a não haver nenhuma transmissão de ruído vibracional do laboratório para esta, deve-se minimizar o ruído microfônico produzido nessa fiação por oscilações mecânicas, uma vez que ela não utiliza nenhum sistema de isolamento vibracional. Com o intuito de resolver este problema, projetamos uma estrutura, formada por pequenos cilindros conectados por barras, a qual não terá nenhuma ressonância mecânica na faixa de freqüências de interesse para detecção (3000 - 3400 Hz). Desta forma, as vibrações nessa faixa não serão amplificadas. O projeto foi feito usando iterativamente, de maneira a otimizar os resultados obtidos, o programa de elementos finitos Msc/Nastran. Através de simulações feitas neste programa, determinamos os parâmetros geométricos ideais a serem utilizados, os quais proporcionam a maior região espectral de interesse livre de ressonâncias.

Vieira, S. J.., Jr.; Melo, J. L.

2003-08-01

437

The influence of changes in lifestyle and mercury exposure in riverine populations of the Madeira River (Amazon Basin) near a hydroelectric project.  

PubMed

In the Amazon Basin, naturally occurring methylmercury bioaccumulates in fish, which is a key source of protein consumed by riverine populations. The hydroelectric power-plant project at Santo Antônio Falls allows us to compare the Hg exposure of riverine populations sparsely distributed on both sides of the Madeira river before the area is to be flooded. From 2009 to 2011, we concluded a population survey of the area (N = 2,008; representing circa 80% of community residents) that estimated fish consumption and mercury exposure of riverine populations with different degrees of lifestyle related to fish consumption. Fish samples from the Madeira river (N = 1,615) and 110 species were analyzed for Hg. Hair-Hg was significantly lower (p < 0.001) in less isolated communities near to the capital of Porto Velho (median 2.32 ppm) than in subsistence communities in the Cuniã Lake, 180 km from Porto Velho city (median 6.3 ppm). Fish Hg concentrations ranged from 0.01 to 6.06 µg/g, depending on fish size and feeding behavior. Currently available fish in the Madeira river show a wide variability in Hg concentrations. Despite cultural similarities, riparians showed hair-Hg distribution patterns that reflect changes in fish-eating habits driven by subsistence characteristics. PMID:24577285

Hacon, Sandra S; Dórea, José G; Fonseca, Márlon de F; Oliveira, Beatriz A; Mourão, Dennys S; Ruiz, Claudia M V; Gonçalves, Rodrigo A; Mariani, Carolina F; Bastos, Wanderley R

2014-03-01

438

EL CUIDADO DE SÍ DE LA EMBARAZADA DIABÉTICA COMO UNA VIA PARA ASEGURAR UN HIJO SANO SELF-CARE OF DIABETIC PREGNANT WOMEN, A WAY OF ENSURING A HEALTHY BABY O CUIDADO DE SI DE GESTANTES DIABÉTICAS COMO UM CAMINHO PARA ASSEGURAR UM FILHO SAUDÁVEL  

Microsoft Academic Search

This focused ethnography explored the beliefs, values, habits and behavioral patterns of diabetic pregnant women who were treated in Hospital Doutor Enrique Tejera, residents of three poor, urban communities in the city of Valencia, Venezuela. The purpose of this study was to find the meaning of self-care for these pregnant women. The Health Analysis, the Theory of Diversity, and the

Carmen Amarilis; Guerra de Castillo; Marta Lucía Vásquez

2006-01-01

439

Determining the Appropriate Levels of Exchange Rates for Developing Economies: Some Methods and Issues (Comment déterminer le taux de change approprié pour un pays en développement: quelques méthodes et problèmes d'analyse) (Determinación del nivel apropiado para los tipos de cambio de las economías en desarrollo: Algunos métodos y problemas)  

Microsoft Academic Search

The paper reviews a number of approaches that are available for determining an appropriate exchange rate that yields a sustainable balance on the external current account for a developing economy, given appropriate monetary, fiscal, and income policies. The study focuses on two aspects of the exchange rate issue--assessing the appropriateness of the prevailing exchange rate, and, if the exchange rate

Ahsan H. Mansur

1983-01-01

440

Complicaciones gastrointestinales (PDQ®)  

Cancer.gov

Resumen de información revisada por expertos acerca del estreñimiento, impacción, obstrucción intestinal y diarrea como complicaciones del cáncer o su tratamiento. Se discute el manejo de estos problemas.

441

Luz, cámara, acción: el cine y la matemática  

Microsoft Academic Search

1 sostiene que al evaluar un problema siempre se tiende a seguir un patrón natural o habitual de pensamiento (las sillas son para sentarse, el piso para caminar, un vaso para ser llenado con un líquido, etc.), lo cual nos limita. Este tipo de pensamiento es el llamado vertical, se caracteriza por encontrar una única solución al problema. Mientras tanto,

CLAUDIA MINNAARD; VIVIANA JULIA CONDESSE; Edward de Bono

442

Desnutrición a Nivel Municipal en Colombia, Censo 2005  

Microsoft Academic Search

Este trabajo va encaminado a resolver el problema de localización y cuantificación de la desnutrición en Colombia, para pequeñas áreas (municipios y localidades para Bogotá). Aquí se presentan los mapas de desnutrición para pequeñas áreas en Colombia, pues con el objetivo de reducir los niveles de desnutrición las entidades gubernamentales requieren herramientas para identificar los problemas a nivel regional y

Hermes Fernando Martínez

2010-01-01

443

Detección de huevos helmintos mediante plantillas dinámicas  

Microsoft Academic Search

La detección de micro-organismos es un problema abierto, donde diferentes técnicas deben ser utilizadas dependiendo del dominio de imágenes en el que se trabaje. El problema que nuestro grupo viene atacando es el referido a la detección de huevos de helmintos en micrografías adquiridas a partir de muestras biológicas. Una característica de estas muestras es la referida a la presencia

J. Chuctaya; J. P. Mena-Chalco; G. Humpire; A. Rodriguez; C. Beltrán; R. Patiño

2010-01-01

444

[Malaria and hematological aspects among residents to be impacted by reservoirs for the Santo Antônio and Jirau Hydroelectric Power Stations, Rondônia State, Brazil].  

PubMed

In Rondônia State, Brazil, two new hydroelectric plants, Santo Antônio and Jirau, are scheduled for construction on the Madeira River, upriver from the State capital, Porto Velho. The current study analyzes malaria prevalence before the construction and provides information on the possible impacts of malaria burden related to the influx of thousands of persons attracted by direct and indirect employment opportunities. According to the findings, malaria is present throughout the region, with varying prevalence rates. The existence of potential asymptomatic malaria carriers among the local population may be epidemiologically relevant and should be considered in the malaria control programs organized by public authorities and companies responsible for building the power plants, aimed at early diagnosis and treatment, vector control, water supply, and infrastructure in the urban areas. PMID:19578569

Katsuragawa, Tony Hiroshi; Cunha, Roberto Penna de Almeida; de Souza, Daniele Cristina Apoluceno; Gil, Luiz Herman Soares; Cruz, Rafael Bastos; Silva, Alexandre de Almeida E; Tada, Mauro Shugiro; da Silva, Luiz Hildebrando Pereira

2009-07-01

445

Neurodevelopment of Amazonian infants: antenatal and postnatal exposure to methyl- and ethylmercury.  

PubMed

Neurodevelopment as Gesell development scores (GDSs) in relation to mercury exposure in infants (<6 months of age) of one urban center and two rural villages, respectively, of fisherman and cassiterite miners. Mean total hair-Hg (HHg) concentrations of infants from Itapuã (3.95 ± 1.8?ppm) were statistically (P = 0.0001) different from those of infants from Porto Velho (3.84 ± 5.5?ppm) and Bom Futuro (1.85 ± 0.9?ppm). Differences in vaccine coverage among these populations resulted in significantly higher (P = 0.0001) mean ethylmercury (EtHg) exposure in urban infants (150??g) than in infants from either village (41.67??g, Itapuã; 42.39??g, Bom Futuro). There was an inverse significant (Spearman r = -0.2300; P = 0.0376) correlation between HHg and GDS for infants from Porto Velho, but not for the rural infants from Bom Futuro (Spearman r = 0.1336; P = 0.0862) and Itapuã (Spearman r = 0.1666; P = 0.5182). Logistic regression applied to variables above or below the median GDS showed that EtHg exposure (estimated probability = -0.0157; P = 0.0070) and breastfeeding score (estimated probability = -0.0066; P = 0.0536) score were significantly associated with GDS. Conclusion. In nurslings whose mothers are exposed to different levels of fish-MeHg (HHg), a higher score of neurological development at six months was negatively associated with exposure to additional TCV-EtHg. Results should be interpreted with caution because of unaccounted variables. PMID:22619491

Dórea, José G; Marques, Rejane C; Isejima, Cintya

2012-01-01

446

Neurodevelopment of Amazonian Infants: Antenatal and Postnatal Exposure to Methyl- and Ethylmercury  

PubMed Central

Neurodevelopment as Gesell development scores (GDSs) in relation to mercury exposure in infants (<6 months of age) of one urban center and two rural villages, respectively, of fisherman and cassiterite miners. Mean total hair-Hg (HHg) concentrations of infants from Itapuã (3.95 ± 1.8?ppm) were statistically (P = 0.0001) different from those of infants from Porto Velho (3.84 ± 5.5?ppm) and Bom Futuro (1.85 ± 0.9?ppm). Differences in vaccine coverage among these populations resulted in significantly higher (P = 0.0001) mean ethylmercury (EtHg) exposure in urban infants (150??g) than in infants from either village (41.67??g, Itapuã; 42.39??g, Bom Futuro). There was an inverse significant (Spearman r = ?0.2300; P = 0.0376) correlation between HHg and GDS for infants from Porto Velho, but not for the rural infants from Bom Futuro (Spearman r = 0.1336; P = 0.0862) and Itapuã (Spearman r = 0.1666; P = 0.5182). Logistic regression applied to variables above or below the median GDS showed that EtHg exposure (estimated probability = ?0.0157; P = 0.0070) and breastfeeding score (estimated probability = ?0.0066; P = 0.0536) score were significantly associated with GDS. Conclusion. In nurslings whose mothers are exposed to different levels of fish-MeHg (HHg), a higher score of neurological development at six months was negatively associated with exposure to additional TCV-EtHg. Results should be interpreted with caution because of unaccounted variables.

Dorea, Jose G.; Marques, Rejane C.; Isejima, Cintya

2012-01-01

447

O DESENVOLVIMENTO DE UM GRUPO DE GESTANTES COM A UTILIZAÇÃO DA ABORDAGEM CORPORAL THE DEVELOPMENT OF A GROUP OF PREGNANT WOMEN USING THE BODY APPROACH EL DESARROLLO DE UN GRUPO DE MUJERES EMBARAZADAS CON LA UTILIZACIÓN DEL ABORDAJE CORPORAL  

Microsoft Academic Search

The aim of this research was to identify the emotional and body discomfort expressed by the participants of a group of pregnant women and to describe the body approach resources utilized to relieve the discomforts. An action research strategy was carried out, with a group of pregnant women composed of eight women and four companions. The group was carried out

Luciana Magnoni Reberte; Luiza Akiko; Komura Hoga; Reberte LM; Hoga LAK

2005-01-01

448

AN EXPLORATORY STUDY OF THE ROLE OF INTERNET TECHNOLOGIES IN THE FIELD OF INDUSTRIAL MAINTENANCE: IS KNOWLEDGE MANAGEMENT THE WAY FORWARD? UM ESTUDO EXPLORATÓRIO DO PAPEL DAS TECNOLOGIAS DE INTERNET NO CAMPO DE MANUTENÇÃO INDUSTRIAL: GESTÃO DO CONHECIMENTO É O  

Microsoft Academic Search

This is an exploratory study of how Internet technologies are likely to have an impact on a specific industrial activity. Maintenance has long been the poor relation in industry despite being indispensable both in continuous process manufacturing and in discrete production. The research starts from the premise that maintenance has two key functions that can be related to management disciplines.

Tim White

449

Consequencia da operacao das bombas de refrigeracao do reator durante um acidente de perda de refrigerante primario por grande ruptura. (Consequences in the pumps operation during a large loss of coolant accident).  

National Technical Information Service (NTIS)

The event of living on or turning off the operation of the Reactor Cooling Pumps - RCPs, in the case of a Loss of Coolant Accident - LOCA, has been a reason of a lot of studies after the Three Mile Island 2 accident. Thus, it was investigated a large brea...

G. A. Santos G. Sabundjian

1991-01-01

450

Um modelo computacional para determinacao de alternativas de expansao de custo minimo em planejamento de sistemas de transmissao. (A computational model for determining the minimal cost expansion alternatives in transmission systems planning).  

National Technical Information Service (NTIS)

A computational model for determining an economical transmission expansion plan, based in the decomposition techniques is presented. The algorithm was used in the Brazilian South System and was able to find an optimal solution, with a low computational re...

L. M. V. Pinto M. V. F. Pereira A. Nunes

1989-01-01

451

Criação de um curso de 'Design da Mobilidade' na FAAP: uma abordagem transdisciplinar em design e engenharia The creation of a course on 'Mobility Design' at FAAP: a transdisciplinar approach for design and engineering  

Microsoft Academic Search

As a strategic area for the development, transportation represents the focus for new courses and activities: Brazilian projects in this area are appointed as successful 'cases'. Conscious of that reality, FAAP created a course on Mobility Design, with transdisciplinar emphasis and the partnership of enterprises and other technological institutions. This paper describes the methodological structure, relief and predicable consequences for

Ari Antonio; Carlos Armando

452

Um caso de sinovite vilonodular do ombro em adolescente: diagnóstico por imagem e anatomopatológico A case of villonodular synovitis of the shoulder in an adolescent: imaging and pathologic diagnosis  

Microsoft Academic Search

Chronic monoarthritis demand an investigation of inflammatory diseases, such as rheumatoid arthritis (RA), infectious diseases like tuberculosis; and other diseases that cause synovitis and joint effu- sion, such as pigmented villonodular synovitis (PVNS), synovial he- mangioma, synovial osteochondromatosis and arborescence lipoma. We report the case of a young patient with chronic right shoulder monoarthritis, who's magnetic resonance imaging (MRI) showed

453

FATORES DE SUCESSO DE UMA INOV AÇÃO NO CONTEXT O UNIVERSITÁRIO: UM ESTUDO DE CASO DO SETOR PECUÁRIO Success factors of an innovation process in the university context: a case study of cattle sector (Starea)  

Microsoft Academic Search

The subject of this work is the innovation process in the university context. The purpose was, by means of an investigation of a specific innovation case in the cattle sector (Starea), to identify the essential factors that promote the transference of knowledge developed by scientific researches to the market. The methodology was a qualitative study of case. The techniques were:

Dany Flávio Tonelli; André Luiz Zambalde

454

Bipolar disorder first episode and suicidal behavior: are there differences according to type of suicide attempt? A polaridade do primeiro episódio no transtorno bipolar é um preditor para tentativa de suicídio (violenta e não violenta) futura?  

Microsoft Academic Search

Objective: The objective of this study was to test the hypothesis that the polarity of the first mood episode may be a marker for suicidal behavior, particularly the violent subtype. Method: One hundred and sixty-eight patients diagnosed with bipolar disorder (DSM-IV) were grouped according to type of first episode: depression or manic\\/hypomanic. Groups were compared for demographic and clinical variables.

Fernando Silva Neves; Leandro Fernandes Malloy-Diniz; Izabela Guimarães Barbosa; Paulo Marcos Brasil; Humberto Corrêa

455

Condutividade hidraulica nao saturada de um solo podzolico vermelho amarelo da Zona da Mata, Norte de Pernambuco. (Unsaturated hydraulic conductivity of a red-yellow podzolic soil in the Northern Zona da Mata of Pernambuco State - Brazil).  

National Technical Information Service (NTIS)

The determination of the hydraulic conductivity of a Red-Yellow Podzolic Soil was carried out during an experiment in a plot measuring 3.5 m x 3.5 m, at the Experimental Station of Itapirema, Goiania, in Pernambuco State, Brazil. The internal drainage met...

A. Maciel Netto

1994-01-01

456

Estudo das reatividades das oxidacoes eletro-cataliticas de substratos organicos com um complexo de Ru(IV). (Study of reactivities of electro-catalytic oxidation of organic substrates with Ru(IV) complex).  

National Technical Information Service (NTIS)

An electrocatalytic procedure for the oxidation of olefines, ketones, heterocycles and ethers using the Ru(sup IV) oxidant RuO (bpy) (trpy)(sup 2+)(bpy is 2,2 - bipyridine; trpy is 2,2', 2''' - terpyridine), is described. The relative reactivities of the ...

J. M. Madurro S. M. Oliveira J. L. Campos

1988-01-01

457

O Desempenho de Adultos Jovens e Idosos na Iowa Gambling Task (IGT): Um Estudo sobre a Tomada de Decisão Decision-making Capacity of Young Adults and Older Adults as Measured by the Iowa Gambling Task (IGT)  

Microsoft Academic Search

The study aimed to analyze the decision-making capacity of young adults and older adults. The Iowa Gambling Task, which was adapted for the Brazilian Portuguese in the present study, was used to measure decision- making. The sample consisted of 82 healthy persons divided in two groups: Group 1 - 42 young adults and Group 2 - 40 elders. The results

Daniela Di Giorgio Schneider; Maria Alice de Mattos; Pimenta Parente

458

Foreign body aspiration in children and adolescents: experience of a Brazilian referral center* Aspiração de corpo estranho por menores de 15 anos: experiência de um centro de referência do Brasil  

Microsoft Academic Search

Objective: To describe the clinical, radiological and endoscopic characteristics of foreign body aspiration among individuals under the age of 15 treated at a referral center in the city of São Luís, Brazil. Methods: This was a descriptive study using data from the medical charts of patients treated for foreign body aspiration at the Hospital Universitário Materno Infantil between 1995 and

Sílvia Teresa; Evangelista Vidotto; Marco Antonio Barbieri; José Albuquerque de Figueiredo Neto

459

Evaluation of corneal ablation by an optical parametric oscillator (OPO) at 2.94 um and an Er:YAG laser and comparison to ablation by a 193-nm excimer laser  

Microsoft Academic Search

Purpose: This study first evaluated the corneal ablation characteristics of (1) an Nd:YAG pumped OPO (Optical Parametric Oscillator) at 2.94 microns and (2) a short pulse Er:YAG laser. Secondly, it compared the histopathology and surface quality of these ablations with (3) a 193 nm excimer laser. Finally, the healing characteristics over 4 months of cat eyes treated with the OPO

William B. Telfair; Hanna J. Hoffman; Robert E. Nordquist; Richard A. Eiferman

1998-01-01

460

USO de Sensoriamento Remoto Aereo Para Um Estudo de Caso de Desertificacao: Quixaba-Pe (Use of Aerial Remote Sensing in a Case Study of Desertification: Quixaba-Pe).  

National Technical Information Service (NTIS)

The Brasilian semiarid northeast, pointed out as one of the problem regions of the land, is presented, as a consequence of its fragile environment and high risk of desertification. A case of vegetative development in one of the problem sectors, a region o...

V. C. Decarvalho

1986-01-01

461

O Imperio como Argumento: Um Contraponto entre Joaquim Nabuco e o Bispo D. Jose Mauricio da Rocha (The Empire as Argument: A Counterpoint between Joaquim Nabuco and the Bishop Dom Jose Mauricio da Rocha).  

ERIC Educational Resources Information Center

Dialogs with the previous article establishing a comparative analysis between the political acceptance present in the reactionary speech of Dom Jose Mauricio da Rocha and in the monarchist words of Joaquim Nabuco. (PA)

Marson, Izabel Andrade

1998-01-01

462

Toward 0.1-um contact hole process by using water-soluble organic overcoating material (WASOOM)-- Resist flow technology III: study on WASOOM, top flare, and etch characterization  

NASA Astrophysics Data System (ADS)

In our previous experiment for sub-0.15micrometers contact hole, we used water-soluble organic over-coating material (for short: WASOOM) as a barrier layer to distribute thermal stress evenly from top to bottom of contact hole resist. It is assumed that WASOOM inside a contact hole will be acting as a barrier layer (or buffer) so that overhang can be reduced. In this paper we will describe a 0.1micrometers contact hole process with well controlled DICD and good etch profile. In order to get a good WASOOM for this study, lots of water soluble polymers have been evaluated. Our methods for resist flow technique use WASOOM's property that it should not react with photoresist at high temperature. The criteria and chemistry of good WASOOM materials will be described for further study. In addition to WASOOM material, we will also explain the results of top flare by using PVP based WASOOM and appropriate etch processes. For etching characterization, we used C5F8 chemistry for the initial study and then later on it is found that there is some etch stop issue which appears related to surface carbon contamination of the etch front coming from C5F8. This surface contamination issue will be also investigated. Mixed C5F9/CF4 chemistry was introduced to make a more robust etching process. This uses the carbon polymerization of C5F8 for good etching profile and adds a small portion of CF4 to generate radical CF species which will prevent etch stop.

Chun, Jun-Sung; Maeng, Chang H.; Tesauro, Mark R.; Sturtevant, John L.; Oberlander, Joseph E.; Romano, Andrew R.; Sagan, John P.; Dammel, Ralph R.

2001-08-01

463

The molecular beam epitaxy growth and characterization of zinc cadmium selenide/zinc cadmium magnesium selenide-indium phosphide quantum cascade structures for operation in the 3 - 5 um range  

NASA Astrophysics Data System (ADS)

The quantum cascade (QC) laser has captured the interest of researchers for almost three decades. In the early stages, researchers were very interested in proving the QC concept1 proposed by Kazarinov and Suris in 1971. This new concept gave researchers hope that very bulky energy inefficient infra-red (IR) lasers would be replaced with ones that are very compact, tunable and portable. Since the proposal of the QC laser concept and its first demonstration by researchers at Bell Laboratories2 in 1994, this technology has progressed to the point where it is now finding commercial applications in a variety of areas such as military counter measures, free space telecommunications, infra-red imaging and chemical spectroscopy.3-5 The success of this technology can be attributed to the coming of age of the techniques of molecular beam epitaxy (MBE) semiconductor growth and bandgap engineering. 6,7 Using MBE technology, the temperature of the source material can be stabilized by making use of a combination of proportional integral derivative (PID) controllers and thermocouple feedbacks. As a result, the material flux from the effusion cells can achieve stability better than (+/-) 1%. This flux stability together with a well-developed computer controlled shuttering mechanism make it possible to grow multi-quantum well (MQW) structures with excellent layer thickness precision (mono-layer scale) and interface quality. This stringent control of material flux is also a tool that is used by MBE growers to vary the material compositions for the growth of lattice matched and strain compensated QC structures. Today, MBE stands out as one of the premier methods for growing high performing QC lasers. The first successful demonstration of a QC laser2 was done using the InGaAs/InAlAs-InP material system. This demonstration was then repeated a few years later using GaAs/AlGaAs-InP.8 These III-V material systems were extensively studied to establish their material parameters. Given that material parameters are critically important in the process of modeling QC structures, it is not surprising that early success was achieved using these systems. Today, the best performing QC lasers operate in the 4--13 mum range and are produced using lattice matched InGaAs/InAlAs-InP. In order to produce short wavelength QC lasers, the well layer thicknesses in the active region of the device must be reduced in an effort to push the lasing energy states further apart. This reduction in well thicknesses results in the movement of the upper lasing state closer to the bandedge. This action increases the probability of the lost of lasing state electrons to the continuum. Therefore, in order to produce high performing short wavelength QC lasers, a large conduction band offset (CBO) is required. The CBO of lattice matched InGaAs/InAlAs-InP is 0.52 eV. In an attempt to produce high performing devices below 4 mum many researchers have resorted to the use of strain compensation9-11 . This approach has yielded very little improvement in performance due to electron scattering to the X and L intervalleys. This has lead to the exploration of wide bandgap material systems such as the antominides and nitrides. In this work the wide bandgap II-V Znx'Cd(1-x')Se/Zn xCdyMg(1-x-y)Se-InP will be explored for QC laser fabrication. To this end, QC lasers were designed for operation at 3--5 mum range. A Matlab-based program was written to calculate the energy level spacing within the active region of these devices. This simulation program was based on Schroindger's equation and the transfer matrix technique. Several calibration samples were grown to establish the doping levels and growth rate of the well and barrier materials. The growth rate was measured using scanning electron microscopy (SEM) and reflection high energy electron diffraction (RHEED) oscillations during MBE growth. X-ray diffraction measurements were performed to determine the lattice mismatch of the II-VI bulk layers, and therefore predict whether material composition adjustments were required to attain the lattice

Charles, William O.

464

Medidad de Qualidade de Estimadores de Proporcoes de Classes Dentro de Um Pixel de Imagens de Satelite (Quality Measures for Estimating the Proportions of Different Classes within a Single Image Resolution Element (Pixel)).  

National Technical Information Service (NTIS)

Methods based on statistical regression models are proposed for estimating the proportion of different classes within a single image resolution element, or pixel. The variance of the estimators depends on the geometry defined by the statistical average ve...

N. D. D. Mascarenhas V. R. M. Correia

1983-01-01

465

A Study of the Vertical Transport of Momentum, Sensible Heat, and Water Vapor over Vegetation-Covered Surfaces in the Tropics Um Estudo DOS Transportes Verticais de Momentum, Calor Sensivele Vapor d'Agua Sobre Superficie Vegetada Nos Tropicos.  

National Technical Information Service (NTIS)

The energy balance changes with aerodynamic characteristics of the surface for four successive crop stage are presented. Parameterizations are used to calculate the sensible and water vapor fluxes. The results of the momentum, sensible heat and water vapo...

R. G. B. Andre

1981-01-01

466

Influence of toothbrushing on enamel softening and abrasive wear of eroded bovine enamel: an in situ study Influência da escovação no amolecimento superficial do esmalte e desgaste do esmalte bovino erodido: um estudo in situ  

Microsoft Academic Search

This study assessed the surface softening and abrasive wear of eroded bovine enamel with or without the influence of toothbrushing. Five volunteers took part in this in situ study of 5 days. They wore acrylic palatal appliances containing 6 bovine enamel blocks divided in two rows with 3 blocks, which corresponded to the stud- ied groups: erosion without toothbrushing (GI)

Braz Oral Res; Daniela Rios; Heitor Marques Honório; Ana Carolina Magalhães; Marília Afonso; Rabelo Buzalaf; Regina Guenka Palma-Dibb; Maria Aparecida De Andrade; Moreira Machado; Salete Moura; Bonifácio da Silva

467

PROPOSIÇÕES DE DIFUSÃO DE CIÊ?CIA E TECOLOGIA: UM ESTUDO DE CASO DE UMA PROPRIEDADE RURAL DO MUICÍPIO DE DRACEA, SP PROPOSAL OF SCIECE AD TECHOLOGY DIFFUSIO?: A CASE STUDY OF A RURAL PROPERTY IDRACEA, SP  

Microsoft Academic Search

The adoption of production techniques and technologies is necessary to increase efficiency in any activity. In the rural area it is not different. However, to achieve best results, they have to be adapted to family's social-economic characteristics, as well as to production and property features. Thus, the aim of this working-paper is to propose some techniques and technologies to improve

Ferenc Istvan Bánkuti; McLean Mcabb

468

Polimorfismo dos Fragmentos de Restricao do DNA Ribossomal em Taxonomia Molecular de Leveduras: Estudo de um Genero (Restriction Fragment Polymorphism of Ribosomal DNA in Yeasts Molecular Taxonomy: Study of a Genus).  

National Technical Information Service (NTIS)

The study explored the possibility of obtaining species-specific probes based on cloned spacer sequences of rDNA using the type strain of the yeast Metschnikowia reukaufii as a model. The study isolated, cloned and mapped its rDNA. Subsequently sub-clones...

M. O. I. Henriques

1990-01-01

469

Saúde Mental na atenção básica à saúde de Campinas, SP: uma rede ou um emaranhado? Mental health in the primary care system of Campinas, SP: network or spider's web?  

Microsoft Academic Search

This article relates a study on the organi- zation of the mental health services in the primary care network of the city of Campinas (SP), begin- ning with the implantation of the management model called Matrix Support. This organizational arrangement is aimed at integrating primary and mental care by redirecting indiscriminate actions to the logic of co-responsibility in order to

Mariana Dorsa Figueiredo; Rosana Onocko Campos

470

Risk Factors For Postpartum Depression In A Well-Child Clinic: Maternal And Infant Characteristics Bir Sa?likli Çocuk Poliklini?inde Do?um Sonrasi Depresyonda Risk Faktörleri: Anneye ve Bebe?e Ait Özellikler  

Microsoft Academic Search

Aim: The aim of this study was to identify possible risk factors for postpartum depression deve- lopment in mothers of infants who were brought to fi rst-month well-child visits. Material and methods: Self-reports were obtained from 103 mothers. The interviews collected data on mothers' sociodemographic and health characteristics, and infants' characteristics. The Edinburgh Postpartum Depression Scale (EPDS) was used to

Filiz ?im?ek Orhon; Betül Ulukol; Atilla Soykan

471

X-Ray Emission Through a Black Hole in Dense Clouds of Interstellar Medium Emissao de Raios-X Por Um Buraco Negro Em Uma Nuvem Densa Do Meio Interestelar.  

National Technical Information Service (NTIS)

A theoretical model is proposed for the emission of X-rays by a black hole in a dense cloud, immersed in a magnetic field. It is based on the Schwartzman model which considers synchrotron emission (the only relevant emission mechanism) by a black hole in ...

E. G. Desouza

1978-01-01

472

Development of transgenic papayas expressing the coat protein gene from a Brazilian isolate of Papaya ringspot virus (PRSV) = Desenvolvimento de mamoeiros transgênicos resistentes a vírus expressando o gene da capa protéica de um isolado brasileiro de Papaya ringspot virus  

Microsoft Academic Search

Translatable and nontranslatable versions of the coat protein (cp) gene of a Papaya ringspot virus (PRSV) isolate collected in the state of Bahia, Brazil, were engineered for expression in Sunrise and Sunset Solo varieties of papaya (Carica papaya). The biolistic system was used to transform secondary somatic embryo cultures derived from immature zygotic embryos. Fifty-four transgenic lines, 26 translatable and

M. T. Souza; O. Níckel; D. Gonsalves

2005-01-01

473

Risoluzione analitica delle equazioni algebriche generali  

Microsoft Academic Search

\\u000a Sunto  L’A. richiama la attenzione dei matematici sul secolare problema della risoluzione delle equazioni algebriche e ricorda che,\\u000a intorno al 1920, questo problema ha avuto una esauriente e generale soluzione mediante le funzioni ipergeometriche di più\\u000a variabili.\\u000a \\u000a L’A. indica che la soluzione di questo problema è stata data da due punti di vista differenti e mostra che, mediante i risultati\\u000a dell’A.,

G. Belaedinelli

1959-01-01

474

Intellectual Disability  

MedlinePLUS

... enfermedad o un problema en el cerebro. En muchos niños no se conoce la causa del discapacidad ... los niños más tarde en la vida. Hay muchos síntomas de discapacidad intelectual. Por ejemplo, los niños ...

475

Complicaciones gastrointestinales (PDQ®)  

Cancer.gov

Resumen de información revisada por expertos acerca del estreñimiento, la retención fecal, la obstrucción intestinal y la diarrea como complicaciones del cáncer o su tratamiento. Se discute el manejo de estos problemas.

476

Ordinary Duality Vis-A-Vis Geometric Duality.  

National Technical Information Service (NTIS)

The ordinary dual problem is characterized as an orthogonal projection of the corresponding geometric dual problem--a projection that can be obtained via a suboptimization. This characterization endows geometric duality with certain strong advantages over...

E. L. Peterson

1976-01-01

477

Análisis de sensibilidad en elasticidad mediante el método de los elementos de contorno  

Microsoft Academic Search

Se presenta en este artículo una revisión completa del análisis de sensibilidad para los funcionales más\\u000ahabituales en Elasticidad, en base al enfoque continuo del problema, teniendo en cuenta los conceptos de\\u000aderivada material y problema adjunto. La precisión en el cálculo de las sensibilidades depende en gran\\u000amedida de la precisión en el cálculo de las tensiones y deformaciones

Elena Calvo; Luis Gracia

1970-01-01

478

Optimización basada en confiabilidad por medio de redes neuronales y algoritmos evolutivos  

Microsoft Academic Search

A diferencia de la optimización usual, la optimización estocástica consiste en una minimización de una\\u000afunción de coste sujeta a condiciones expresadas en forma de probabilidades en lugar de funciones deterministas,\\u000alo que la convierte en un problema mucho más complejo. En esta clase de optimización son comunes\\u000alos problemas donde la función o funciones objetivo y sus condiciones son

J. E. Hurtado; Diego Álvarez

1970-01-01

479

Recognition and characterisation of high-grade ignimbrites from the Neoproterozoic rhyolitic volcanism in southernmost Brazil  

NASA Astrophysics Data System (ADS)

Neoproterozoic magmatism in southern Brazil is associated with translithospheric shear belts and strike-slip basins in a post-collisional setting related to the last stages of the Brasilian-Pan African Orogenic Cycle. It evolved from an association of high-K calc-alkaline, leucocratic-peraluminous and continental tholeiitic magmas, to an association with shoshonitic magmas and, eventually, to an association with magmas of the sodic mildly alkaline series. This magmatism varies from metaluminous to peralkaline and exhibits alkaline sodic affinity. A large volcanism is related to this alkaline sodic magmatism and is named the Acampamento Velho Formation. This unit was coeval with subaerial siliciclastic sedimentation in post-collisional basins preserved in the region. The Acampamento Velho Formation consists of pyroclastic and effusive volcanic deposits, which are mainly silicic, emplaced under subaerial conditions. The best exposures of this volcanism occur on the Ramada and Taquarembó plateaus, located southwest of Rio Grande do Sul in southernmost Brazil. The pyroclastic flow deposits are composed mainly of juvenile fragments such as pumices, shards and crystal fragments. Welding is very effective in these units. High-grade ignimbrites occur at the base and intermediate portions of the deposits and rheoignimbrites are observed at the top. The pre-eruptive temperature calculations, which were obtained at the saturation of zircon, revealed values between 870 °C and 978 °C for Taquarembó Plateau and 850 °C-946 °C for Ramada Plateau. The calculated viscosity values vary from 6.946 to 8.453 log ? (Pas) for the rheoignimbrites and 7.818 to 10.588 log ? (Pas) for the ignimbrites. Zr contents increase toward the top of the pyroclastic sequence, which indicates an increase in peralkalinity and determines the reduction in viscosity for clasts at the upper portions of the flows. The patterns of the structures of the ignimbrites and rheoignimbrites in the Taquarembó and Ramada plateaus accords well with successive pyroclastic flows that halts en masse. In this model the entire pyroclastic flow halts en masse, so complex vertical changes in grain size and composition are interpreted as recording deposition from successive discrete pyroclastic flows. The stratification observed in intermediate units in Taquarembó Plateau might reflect in this case variation in eruptive dynamics and short pauses.

Sommer, Carlos Augusto; Lima, Evandro Fernandes; Machado, Adriane; Rossetti, Lucas de Magalhães May; Pierosan, Ronaldo

2013-11-01

480

Proterozoic Tectonic History of Borborema Province, NE Brazil: Implications For Assembly of West Gondwana  

NASA Astrophysics Data System (ADS)

The Borborema Province of NE Brazil comprises the west-central part of a wide Pan- African - Brasiliano continental collision belt that formed during ca. 600 Ma assembly of West Gondwana. Our studies over the past decade, in collaboration with many other workers, demonstrate a complex Proterozoic history that created or modified crustal domains at 2.1, 1.7, 1.0, 0.8, and 0.6 Ga. Although NE Brazil contains a few small Archean domains included within early Paleoproterozoic orogens, the first major event was formation of extensive continental crust about 2.35 to 2.1 Ga, before and during the so-called Transamazonian orogeny. We believe that this occurred in conjunction with formation of a larger Paleoproterozoic continent about 2.05 Ga that included present-day West African, Amazonian, Congo, and São Francisco cratons. Incipient extension within this continent occurred in Brazil about 1.8 to 1.7 Ga, resulting in intracratonic sedimentation and bimodal volcanism, but equivalent rocks are less well known in Africa. A successful breakup occurred before or about 1.1 Ga, resulting in separation of parts of this continent into two major stable masses containing (a) the Amazon-West African craton, and (b) the São Francisco-Congo (SF/C) craton. The break-up also created many smaller fragments between these two large masses, particularly in the east (present-day NE Brazil and Saharan Africa) and including the Ceará-Rio Grande do Norte (CE/RN) craton in NE Brazil. About 1.0 Ga a magmatic arc more than 700 km long (Cariris Velhos orogen) developed in NE Brazil, possibly as a result of convergence between the CE/RN and SF/C cratons; eastward extension of the 1.0 Ga Cariris Velhos orogen into West Africa is presently unknown. About 850 to 700 Ma several extensional basins developed in NE Brazil, with intraplate bimodal volcanism and clastic sedimentation; coeval basins may have formed in west-central Africa. From 700 to 600 Ma plate convergence among the CE/RN craton, SF/C craton, Amazon-West African craton, and several other microcontinents (e.g., Nigerian block) culminated in formation of West Gondwana. Accretion of pre-600 Ma juvenile oceanic arcs occurred elsewhere in Brazil and West Africa, but such terranes have not been found in NE Brazil. The continental collisions in NE Brazil began about 640 to 630 Ma, peaked about 610-590 Ma, and were followed by 580-570 Ma post-tectonic plutonism. Collisional tectonism, including transcurrent faulting associated with escape tectonics, continued through much of the Cambrian.

van Schmus, W. R.; Brito Neves, B. B.

481

Ground based chemical characterization of submicron aerosol during the South American Biomass Burning Analysis (SAMBBA) field experiment  

NASA Astrophysics Data System (ADS)

This work presents the results of an Aerosol Chemical Speciation Monitor (ACSM) which was successfully operated at a ground station in Porto Velho, Brazil, during the South American Biomass Burning Analysis (SAMBBA). SAMBBA is an international research project based on experimental and modeling activities designed to investigate the impacts of biomass burning emissions on climate, air quality and numerical weather prediction over South America. The measurement program was headed by the deployment of UK's Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft over Brazil during the dry season of 2012. The aircraft operation was coordinated with ground-based measurements at Porto Velho, operated by the University of Sao Paulo. Besides the aerosol chemical speciation, continuous measurements of aerosol size distribution and optical properties were carried out at the ground station, together with CO, CO2 and O3. Filters for trace elements measured by XRF and for OC/EC determined using a Sunset instrument were also collected at the ground based component of SAMBBA. The ACSM collected data for three weeks during September 2012. This period included a strong biomass burning event which showed a marked peak in f60, linked with Levoglucosan, a well-known biomass burning marker. During the biomass burning event, organics concentrations rose up to 80 ?g/m3, black carbon close to 6 ?g/m3 and CO mixing ratio above 2 ppmv. Fast biomass burning aerosol processing in the atmosphere could be observed through the relative contributions of C2H3O+ vs. CO2+ relative to total organic mass (f44 vs. f43). A clear diurnal variation throughout the sampling period has been observed for organic aerosols with a median peak of 9 ?g/m3 at 04:00 LT and a minima of 5 ?g/m3 at 18:00 LT. Preliminary results indicate that organics are responsible for 85% of PM1 non-refractory aerosols. The data set will allow the study of interactions between biomass burning and biogenic emissions, focusing on changes in the radiation balance, atmospheric chemistry and effects on the terrestrial biosphere including carbon uptake by the Amazonian forest.

Brito, Joel; Artaxo, Paulo; Varanda Rizzo, Luciana; Johnson, Ben; Haywood, Jim; Longo, Karla; Freitas, Saulo; Coe, Hugh

2013-04-01

482

A hibonite-corundum inclusion from Murchison: A first-generation condensate from the solar nebula  

Microsoft Academic Search

Through freeze-thaw disaggregation of the Murchison (CM) carbonaceous chondrite, we have recovered a ~90 x 75 um refractory inclusion that consists of corundum and hibonite with minor perovskite. Corundum occurs as small (~10 um), rounded grains enclosed in hibonite laths (~10 um wide and 30-40 um long) throughout the inclusion. Perovskite predominantly occurs near the edge of the inclusion. The

S. B. Simon; A. M. Davis; L. Grossman; K. D. McKeegan

2002-01-01

483

Navegando na Rede Semantica dos Topic Maps com o Ulisses  

Microsoft Academic Search

A norma ISO-IEC 13250 Topic Maps, composta principal- mente de topicos interligados atraves de associacoes, define uma rede semantica estruturada sobre um sistema de informacao, criando uma ponte entre a gestao de informacao e os dom´inios de representacao de conhecimento. A estrutura de dados que um topic map representae um grafo; portanto, uma das melhores maneiras de visualizar um grafoe

Giovani Rubert Librelotto; Renato Preigschadt de Azevedo; Jose Carlos Ramalho; Pedro Rangel Henriques

484

Mutation in a heat-regulated hsp70 gene of Ustilago maydis.  

PubMed

Four genes (ums1, ums2, ums3 and ums4) representing an hsp70-related gene family were isolated from a genomic library of Ustilago maydis. All four genes are transcriptionally active during normal growth. Following a heat shock, the mRNA levels of ums1 and ums2 increase by approximately 5-fold, whereas the ums3 transcript becomes less abundant. The amount of ums4 mRNA remains relatively unchanged after heat treatment. The nucleotide sequence of the 5' non-coding and a portion of the ums2 coding region was determined. The sequence encoding the first 90 amino acids is 73% identical to corresponding regions of the Drosophila and yeast (SSA1) hsp70 genes. To investigate the effect of a mutation in ums2, a plasmid was constructed in which most of the transcriptional unit of ums2 was deleted and substituted with the Escherichia coli hygromycin B (hygB) phosphotransferase gene. Transcription of this gene is controlled by the ums2 promoter, allowing the expression of hygB resistance in Ustilago. The marker was introduced into diploid cells as a linear sequence with termini homologous to the 5' and 3' flanking regions of ums2. In approximately 50% of transformants examined, one of the two wild-type ums2 alleles had been replaced by the mutated sequence, demonstrating the feasibility of using one-step gene disruption to create heterozygous diploids in Ustilago. The ums2/ums2::hygBr heterozygote produced teliospores after injection into corn plants, but only cells carrying functional ums2 were found among their meiotic progeny. Therefore ums2::hygBr segregates as a recessive lethal, which strongly suggests that ums2 is essential for growth in Ustilago. PMID:2792075

Holden, D W; Kronstad, J W; Leong, S A

1989-07-01

485

Pego do Diabo (Loures, Portugal): Dating the Emergence of Anatomical Modernity in Westernmost Eurasia  

PubMed Central

Background Neandertals and the Middle Paleolithic persisted in the Iberian Peninsula south of the Ebro drainage system for several millennia beyond their assimilation/replacement elsewhere in Europe. As only modern humans are associated with the later stages of the Aurignacian, the duration of this persistence pattern can be assessed via the dating of diagnostic occurrences of such stages. Methodology/Principal Findings Using AMS radiocarbon and advanced pretreatment techniques, we dated a set of stratigraphically associated faunal samples from an Aurignacian III–IV context excavated at the Portuguese cave site of Pego do Diabo. Our results establish a secure terminus ante quem of ca.34,500 calendar years ago for the assimilation/replacement process in westernmost Eurasia. Combined with the chronology of the regional Late Mousterian and with less precise dating evidence for the Aurignacian II, they place the denouement of that process in the 37th millennium before present. Conclusions/Significance These findings have implications for the understanding of the emergence of anatomical modernity in the Old World as a whole, support explanations of the archaic features of the Lagar Velho child's anatomy that invoke evolutionarily significant Neandertal/modern admixture at the time of contact, and counter suggestions that Neandertals could have survived in southwest Iberia until as late as the Last Glacial Maximum.

Zilhao, Joao; Davis, Simon J. M.; Duarte, Cidalia; Soares, Antonio M. M.; Steier, Peter; Wild, Eva

2010-01-01

486

Distribution of the CCR5delta32 allele (gene variant CCR5) in Rond?nia, Western Amazonian region, Brazil  

PubMed Central

Since around 1723, on the occasion of its initial colonization by Europeans, Rondonia has received successive waves of immigrants. This has been further swelled by individuals from northeastern Brazil, who began entering at the beginning of the twentieth century. The ethnic composition varies across the state according to the various sites of settlement of each wave of immigrants. We analyzed the frequency of the CCR5?32 allele of the CCR5 chemokine receptor, which is considered a Caucasian marker, in five sample sets from the population. Four were collected in Porto Velho, the state capital and the site of several waves of migration. Of these, two, from the Hospital de Base were comprised of HB Mothers and HB Newborns presenting allele frequencies of 3.5% and 3.1%, respectively, a third from the peri-urban neighborhoods of Candelária/Bate-Estaca (1.8%), whereas a fourth, from the Research Center on Tropical Medicine/CEPEM (0.6%), was composed of malaria patients under treament. The fifth sample (3.4%) came from the inland Quilombola village of Pedras Negras. Two homozygous individuals (CCR5?32/CCR5?32) were detected among the HB Mother samples. The frequency of this allele was heterogeneous and higher where the European inflow was more pronounced. The presence of the allele in Pedras Negras revealed European miscegenation in a community largely comprising Quilombolas.

de Farias, Josileide Duarte; Santos, Marlene Guimaraes; de Franca, Andonai Krauze; Delani, Daniel; Tada, Mauro Shugiro; Casseb, Almeida Andrade; Simoes, Aguinaldo Luiz; Engracia, Vera

2012-01-01

487

The impacts of land use changes in the mercury flux in the Madeira River, Western Amazon.  

PubMed

Changes in hydrochemistry and Hg distribution in the Madeira River from Porto Velho to the confluence with the Amazon River were studied in two cruises in 1997 and 2002. Water conductivity was similar in both periods, but the pH was significantly higher in 2002, in particular along the middle reaches of the river. Total suspended matter concentrations also increased from 1997 to 2002 along the same river portion, which is a result of forest conversion to other land uses, in particular pastures and agriculture accelerated during the interval between the cruises. Dissolved Hg concentrations were similar along the river in both cruises, but particulate Hg concentrations increased significantly along the middle portion of the river, although the suspended matter from 2002 was relatively poorer in Hg compared to that from 1997. Since particulate Hg represents more than 90% of the total Hg present in the river water, there was a significant increase in the total Hg transport in the Madeira River. Although gold mining has nearly ceased to exist in the region, the remobilization of Hg from forest soils through conversion to other land uses is responsible for maintaining relatively high Hg content in the Madeira River environment. PMID:22441596

Lacerda, Luiz D; Bastos, Wanderley R; Almeida, Marcelo D

2012-03-01