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  1. Curva dos valores normais de peso fetal estimado por ultra-sonografia segundo a idade gestacional

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    José Guilherme Cecatti

    Full Text Available Este trabalho teve por objetivo avaliar a evolução do peso fetal estimado em gestações normais de 20 a 42 semanas. Quanto ao desenho e métodos empregados na pesquisa, realizou-se estudo descritivo de um universo constituído por 2.874 gestantes normais da cidade de Campinas, efetuando-se exame ultra-sonográfico obstétrico de rotina com medida da biometria fetal e utilizando-se, para o cálculo do peso fetal, a fórmula de Hadlock et al. (1991. Calcularam-se os valores dos percentis 10, 50 e 90 do peso fetal, por idade gestacional, com construção de curva posteriormente alisada mediante ajuste polinomial de 2º grau. Como resultado, obteve-se que o valor do percentil 50 foi de 368 gramas na 20ª semana, 1.512 gramas na 30ª semana, atingindo 3.417 gramas na 42ª semana. Constatou-se ter havido ganho médio de 200 gramas de peso por semana, de 27 a 38 semanas, a partir de quando o incremento diminuiu. Concluiu-se que a disponibilidade de curva brasileira do peso fetal estimado normal permitirá o diagnóstico pré-natal de seus desvios pela ultra-sonografia.

  2. Avaliação do volume de fluxo venoso da bomba sural por ultra-sonografia Doppler durante cinesioterapia ativa e passiva: um estudo piloto Evaluation of venous flow volume of the calf muscle pump by Doppler ultrasound during active and passive kinesiotherapy: a pilot study

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    Carmindo Carlos Cardoso Campos

    2008-12-01

    Full Text Available CONTEXTO: O fisioterapeuta na unidade hospitalar atua sobre os efeitos da hipoatividade ou inatividade do paciente acamado. Na prática diária, a contração do músculo da panturrilha é difundida entre os profissionais de saúde no ambiente hospitalar, principalmente nos períodos de pré e pós-operatório, como forma de diminuir a estase venosa e os riscos de trombose venosa profunda nos membros inferiores. OBJETIVO: Avaliar o volume de fluxo venoso na bomba sural, através de ultra-sonografia doppler, durante cinesioterapia ativa e passiva (flexão plantar do tornozelo. MÉTODOS: A amostra foi constituída por 30 indivíduos escolhidos aleatoriamente e submetidos a ultra-sonografia doppler da veia poplítea direita, visando mensurar o volume de fluxo sanguíneo em quatro momentos: repouso, compressão manual da panturrilha, movimentação passiva e ativa do tornozelo em flexão plantar. Na análise dos resultados, utilizou-se o teste t, sendo utilizado um valor de p BACKGROUND: In-hospital physical therapists work on the effects of hypoactivity or inactivity of bedridden patients. In daily practice, contraction of the calf muscle is commonly performed by health professionals in hospitals, especially in pre- and post-operative periods as a form of reducing venous stasis and risk of deep venous thrombosis in the lower limbs. OBJECTIVE: To assess venous flow volume at the calf muscle pump using color Doppler ultrasound during active and passive kinesiotherapy (ankle plantar flexion. METHODS: The sample consisted of 30 individuals randomly selected and submitted to color Doppler ultrasound of the right popliteal vein, aiming to measure blood flow volume in four periods: rest, manual calf compression, active and passive ankle movement in plantar flexion. The t test was used for statistical analysis, and p < 0.05 was used as an index of statistical significance. RESULTS: The sample consisted of 16 females and 14 males. Means were as follows: age

  3. Avaliação ultra-sonográfica e ao Doppler dos TIPS (anastomose portossistêmica intra-hepática transjugular

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    Machado Márcio Martins

    2004-01-01

    Full Text Available A anastomose portossistêmica intra-hepática transjugular (TIPS compreende a técnica mais recente e mais popular para o alívio da hipertensão portal sintomática, especialmente para os casos com varizes e hemorragia digestiva alta, e menos comumente para o tratamento da ascite refratária. Os TIPS podem apresentar complicações após sua colocação, como as estenoses e oclusões. A ultra-sonografia e o Doppler permitem o estudo dos TIPS de uma forma não invasiva. Neste artigo os autores relatam os achados recentes à ultra-sonografia e ao Doppler nos casos de funcionamento normal e anormal (estenoses/oclusões dos TIPS.

  4. Ultra-sonografia tridimensional em ginecologia: malformações uterinas Three-dimensional ultrasound in gynecology: uterine malformations

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    Adilson Cunha Ferreira

    2007-04-01

    Full Text Available As malformações uterinas são achados pouco comuns na clínica ginecológica. As estatísticas nesta área são muito falhas. Corrobora, ainda, a falta de uniformização na terminologia empregada e as dificuldades diagnósticas. A partir da década de oitenta, a ultra-sonografia tornou-se um procedimento indispensável à prática toco-ginecológica, contribuindo e modificando conceitos e procedimentos dentro dessa especialidade. O advento dos transdutores endocavitários, a análise com Doppler colorido de amplitude e espectral, assim como a melhoria crescente da qualidade de imagem contribuíram para isso. Nos últimos dez anos muito se tem pesquisado, publicado e discutido sobre o papel da ultra-sonografia tridimensional. Os autores fazem uma revisão do tema e ressaltam a importância dessa metodologia como modalidade diagnóstica.Uterine malformations are unusual findings in the clinical practice of gynecology. Statistics regarding this abnormality are flawed, and there is a lack of standardization of the pertinent terminology, besides difficulty in the diagnosis. Starting in the 1980's, ultrasound became a procedure indispensable to the clinical practice in the field of tocogynecology, modifying concepts and procedures, and bringing an important contribution to this specialty. The advent of endocavitary transducers, amplitude and spectral color Doppler, as well as the increasing improvement in the imaging quality, has contributed to this progress. Over the last ten years, much has been studied, published and discussed about the role of the three-dimensional ultrasonography. The authors review the topic and emphasize the importance of this method as a diagnostic modality.

  5. Validação da curva normal de peso fetal estimado pela ultra-sonografia para o diagnóstico do peso neonatal

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    Cecatti José Guilherme; Machado Maria Regina Marrocos; Krupa Fabiana da Graça; Figueiredo Priscila Garcia; Pires Helaine Maria Besteti

    2003-01-01

    OBJETIVO: avaliar a concordância entre o peso fetal estimado (PFE) por ultra-sonografia e o neonatal, o desempenho da curva normal de PFE por idade gestacional no diagnóstico de desvios do peso fetal/neonatal e fatores associados. MÉTODOS: participaram do estudo 186 grávidas atendidas de novembro de 1998 a janeiro de 2000, com avaliação ultra-sonográfica até 3 dias antes do parto, determinação do PFE e do índice de líquido amniótico e parto na instituição. O PFE foi calculado e classificado d...

  6. Effect of intertrochanteric osteotomy on the proximal femur of rabbits: assessment with power Doppler sonography and scintigraphy Efeito da osteotomia intertrocantérica no femur proximal de coelhos: avaliação com utra-sonografia power Doppler e cintilografia

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    Andrea S. Doria

    2007-01-01

    area unit.OBJETIVO: Regeneração em casos de lesão óssea resulta em aumento da vascularização local e remodelamento da medula óssea adjacente. A caracterização imagenológica de padrões vasculares e metabólicos no fêmur proximal após uma osteotomia intertrocantérica pode auxiliar ortopedistas a decidirem qual a terapêutica mais apropriada. O objetivo deste estudo foi avaliar as alterações temporais observadas por ultra-sonografia Doppler e cintilografia no fêmur proximal após a realização de uma osteotomia intertrocantérica; e comparar achados imagenológicos e histomorfométricos no estágio pós-operatório tardio (6 semanas após a cirurgia num modelo animal de lesão óssea. MATERIAIS AND MÉTODOS: Ambos os quadris de 12 coelhos adultos foram examinados por ultra-sonografia power Doppler e cintilografia antes e após (7 dias e 6 semanas uma osteotomia unilateral. A acurácia dos métodos de imagem foi avaliada usando-se o status operatório dos quadris and os resultados histomorfométricos (área vascular fracional e número de vasos/unidade de área como medidas de referência. RESULTADOS: Uma diferença significativa foi observada entre o número médio de pixels presentes no fêmur proximal operado e não-operado ao exame de power Doppler obtido no estágio pós-operatório tardio (P=0.049. Embora ser atingir significância estatística, a área abaixo da curva ("area-under-the-curve" dos exames de power Doppler (AUC=0.99 for numericamente superior à área abaixo da curva dos exames de cintilografia (AUC= 0.857±0.099 (P=0.15 para diferenciar fêmures proximais com relação a suas áreas vasculares fracionais no estágio pós-operatório tardio. Ao contrário, a cintilografia tendeu a apresentar uma "performance" diagnóstica superior (AUC=0.984±0.022 em relação ao Doppler (AUC=0.746±0.131 para demonstrar a quantidade de vasos por unidade de área (P=0.07 no estágio tardio. CONCLUSÃO: Nossos resultados despertam a importância de

  7. Punção Aspirativa por Agulha Fina Orientada por Ultra-Sonografia em Lesões Não-palpáveis Fine Needle Aspiration Cytology Guided by Ultrasound in Nonpalpable Lesions

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    Cláudio Kemp

    2001-06-01

    Full Text Available Objetivo: correlacionar os achados citológicos obtidos por punção com agulha fina dirigida pela ultra-sonografia de lesões não-palpáveis da mama, císticas ou sólidas, os aspectos ultra-sonográficos e os respectivos resultados histopatológicos das lesões que foram submetidas a cirurgia. Métodos: foram analisadas 617 lesões não-palpáveis visualizadas ao ultra-som. Realizou-se a punção aspirativa por agulha fina (PAAF orientada pela ultra-sonografia, com análise citológica do material, diferenciando-as em cistos ou nódulos sólidos. Estes tiveram seu resultado citológico confrontado com o resultado histopatológico, nos casos em que foi realizada a biópsia cirúrgica. Resultados: das 617 lesões não-palpáveis, 471 eram cistos, sendo 451 cistos simples que apresentaram citologia negativa em todos os casos e 20 casos foram considerados cistos complexos. Destes, 3 (15% tiveram resultado citológico positivo ou suspeito e em 2 casos confirmou-se malignidade. Dos 105 nódulos sólidos, 63 apresentaram citologia negativa, sendo 59 concordantes com a biópsia e houve 4 casos (0,3% de resultado falso-negativo pela citologia. Todos, porém, apresentavam discordância entre imagem e citologia. Em 14 nódulos sólidos (13%, a citologia foi suspeita e, destes, 5 foram diagnosticados como carcinoma. Em outros 14 (13%, o material foi insatisfatório e 1 era carcinoma. Em 51 casos, o tríplice diagnóstico foi concordante e optou-se por seguimento clínico. Conclusão: a análise citológica do material dos cistos mamários simples é desnecessária, porém quando são complexos, a citologia é imperativa. Nas lesões sólidas não-palpáveis, é fundamental a correlação da citologia com o aspecto ultra-sonográfico e mamográfico; caso sejam discordantes, deve-se sempre prosseguir a investigação da lesão.Purpose: to determine the relationship between fine needle aspiration cytology guided by ultrasound of nonpalpable breast lesions

  8. Acurácia diagnóstica do espessamento ecogênico periportal à ultra-sonografia e da histopatologia no diagnóstico diferencial da atresia biliar

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    Roquete,Mariza L. V.; Ferreira,Alexandre R.; Fagundes,Eleonora D. T.; Castro,Lúcia P. F.; Silva,Rogério A. P.; Penna,Francisco J.

    2008-01-01

    OBJETIVOS: Definir a sensibilidade, especificidade e a acurácia do espessamento ecogênico periportal à ultra-sonografia e da histopatologia hepática, isolados ou em conjunto, na distinção diagnóstica entre atresia biliar e as colestases intra-hepáticas. MÉTODOS: Trata-se de estudo retrospectivo realizado entre janeiro de 1990 e dezembro de 2004. Foram analisados 51 casos de atresia biliar e 45 com colestase intra-hepática. A histopatologia foi realizada por uma patologista de forma cega. O es...

  9. ASPECTOS ULTRA-SONOGRÁFICOS DA ESQUISTOSSOMOSE HEPATOESPLÊNICA Ultrasound findings in hepatosplenic schistosomiasis

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    Márcio Martins Machado

    2002-01-01

    Full Text Available A ultra-sonografia representa uma importante contribuição no diagnóstico da forma hepatoesplênica da esquistossomose. A ultra-sonografia permite a identificação das principais alterações, como espessamento periportal, perivesicular, aumento do lobo hepático esquerdo, redução do lobo hepático direito e esplenomegalia. Adicionalmente, os padrões hemodinâmicos podem ser avaliados com o Doppler, sendo possível a análise das veias porta, mesentérica superior e esplênica, além de facilitar o estudo dos vasos venosos colaterais. Em áreas endêmicas, a ultra-sonografia assume papel de destaque, sendo superior à avaliação clínica na identificação da hepatoesplenomegalia e possibilitando o acompanhamento dos pacientes submetidos a tratamento clínico. Neste trabalho, os autores apresentam uma revisão dos principais achados sonográficos e ao Doppler da esquistossomose hepatoesplênica, sendo demonstrada, também, a relação destes achados com os aspectos clínico-patológicos desta doença.Ultrasound represents an important contribution to the diagnosis of hepatosplenic mansonic schistosomiasis. Abnormalities such as hyperechoic fibrotic bands along the portal vessels, volumetric reduction of the right hepatic lobe, enlargement of the left lobe, perivesicular fibrotic thickening and splenomegaly can be recognized. Moreover, the hemodynamic status of the portal venous system may also be evaluated by Doppler analysis, including the identification of collateral veins and portosystemic venous shunts. In endemic areas, ultrasound is of great value in the identification of hepatosplenomegaly, allowing follow-up of patients under clinical treatment. This review presents the ultrasonographic and Doppler features of hepatosplenic schistosomiasis. The relationship between these findings and the clinical and pathological characteristics of this disease are also discussed.

  10. Avaliação dos tumores hepáticos ao Doppler Doppler evaluation of liver tumors

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    Márcio Martins Machado

    2004-10-01

    Full Text Available Os avanços recentes na ultra-sonografia têm ampliado a possibilidade de detecção de tumores hepáticos. Isto tem auxiliado na perspectiva de melhora do prognóstico destes pacientes, à medida que novas técnicas terapêuticas têm surgido. Neste artigo os autores relatam achados ao Doppler que podem auxiliar na identificação e caracterização dos tumores hepáticos, avaliando dados do Doppler colorido, pulsado e do Doppler de amplitude ("power Doppler". Fazem, também, referência a novas modalidades de imagem, como o uso da harmônica.Recent advances in ultrasound have optimized the detection of liver tumors and helped to improve the prognosis of patients with this condition as newly developed and improved therapeutic modalities have been established. The authors review important Doppler findings which may help in the identification and characterization of some hepatic tumors through the evaluation of color Doppler, pulsed Doppler and power Doppler features. New imaging methods such as the use of harmonics imaging are also reviewed.

  11. Curva dos valores normais de peso fetal estimado por ultra-sonografia segundo a idade gestacional

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    Cecatti,José Guilherme; Machado,Maria Regina Marrocos; Santos,Fernanda Fioravanti Azank dos; Marussi,Emílio Francisco

    2000-01-01

    Este trabalho teve por objetivo avaliar a evolução do peso fetal estimado em gestações normais de 20 a 42 semanas. Quanto ao desenho e métodos empregados na pesquisa, realizou-se estudo descritivo de um universo constituído por 2.874 gestantes normais da cidade de Campinas, efetuando-se exame ultra-sonográfico obstétrico de rotina com medida da biometria fetal e utilizando-se, para o cálculo do peso fetal, a fórmula de Hadlock et al. (1991). Calcularam-se os valores dos percentis 10, 50 e 90 ...

  12. Pancreatite aguda leve: avaliação pela ultra-sonografia. estudo prospectivo Mild acute pancreatitis: ultrasound evaluation: a prospective study

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    Márcio Martins Machado

    2002-07-01

    Full Text Available Resumo Neste estudo foram avaliados, por meio da ultra-sonografia, 21 pacientes com pancreatite aguda leve. Foram analisadas a presença ou ausência de hipoecogenicidade do pâncreas e a presença ou ausência de líquido peripancreático. Em 19 pacientes (90,5% foi identificada hipoecogenicidade pancreática, e em três (15,8% destes pacientes foi identificada a presença de pequena quantidade de líquido na pequena cavidade dos epíploons. Em dois pacientes (9,5% não se identificou qualquer alteração pancreática. Com relação à possível etiologia da pancreatite aguda, em 15 pacientes (71,5% pôde-se demonstrar a presença de colecistopatia calculosa, em quatro pacientes (19,0% havia história de alcoolismo crônico e não foram identificados cálculos na vesícula biliar, e em dois pacientes (9,5% não foi identificada qualquer causa aparente. Os autores concluem que a ultra-sonografia pode identificar alteração na maioria dos pacientes com pancreatite aguda leve e permite, ainda, o acompanhamento daqueles com pequenas coleções líquidas peripancreáticas.We analyzed the ultrasonographic findings of 21 patients with mild acute pancreatitis. The presence or absence of pancreatic hypoechogenicity and peripancreatic fluid collection was assessed. Pancreatic hypoechogenicity was identified in 19 patients (90.5% whereas small sac fluid collection was identified in 3 (15.8% of these patients. No abnormality was seen in 2 patients (9.5%. Regarding the etiology of acute pancreatitis, cholelithiasis was identified in 15 patients (71.5%, alcohol abuse was identified in 4 patients (19.0%, and in 2 patients (9.5% no probable etiology could be found. The authors conclude that ultrasonography may identify abnormalities in the majority of patients with mild acute pancreatitis and can be used to assess patients with peripancreatic fluid collections.

  13. Valor da ultra-sonografia na avaliação das alterações endometriais em pacientes tratadas com tamoxifeno Value of sonographic endometrial findings in patients under tamoxifen therapy

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    Arildo Corrêa Teixeira

    2007-12-01

    Full Text Available OBJETIVO: Avaliar as alterações endometriais por meio da ultra-sonografia transvaginal e correlacioná-las com os achados da histeroscopia e histologia, em pacientes submetidas a tratamento com tamoxifeno. MATERIAIS E MÉTODOS: No período de janeiro de 2003 a dezembro de 2005, foram incluídas pacientes com câncer de mama usuárias de tamoxifeno que apresentaram espessamento endometrial acima de 5 mm. Os achados foram correlacionados com os dados de histeroscopia e anatomopatologia. RESULTADOS: Foram selecionadas 25 pacientes com idade média de 62,6 anos. O tempo médio do diagnóstico do câncer foi de 4,3 anos e do uso de tamoxifeno, três anos. Vinte pacientes eram assintomáticas (80% e as demais apresentaram sangramento (20%. À ultra-sonografia, 16% apresentaram espessamento endometrial entre 5 mm e 8 mm, 40% entre 9 mm e 15 mm, e 44% acima de 15 mm. Ao estudo com a histeroscopia, 40% apresentaram atrofia, 16% atrofia cística, 28% pólipos, e 16% lesão hiperplásica. O estudo anatomopatológico apresentou-se normal em 35,2% dos casos e mostrou atrofia em 5,8%, pólipo em 29,4% e hiperplasia em 11,7%. Foi observado um caso de adenocarcinoma (5,8%. CONCLUSÃO: A ultra-sonografia associada à histeroscopia apresentam-se como importantes aliados na avaliação de pacientes usuárias de tamoxifeno. A detecção de espessamento endometrial à ultra-sonografia apresenta baixa especificidade, enquanto a histeroscopia é mais acurada na detecção de pólipos, hiperplasia e alterações neoplásicas.OBJECTIVE: To evaluate endometrial alterations by means of transvaginal ultrasound and to correlate them with hysteroscopic and histological findings in patients under tamoxifen therapy. MATERIALS AND METHODS: The present study was developed in the period between January 2003 and December 2005, including patients under tamoxifen therapy for breast cancer, and presenting with endometrial thickening > 5 mm. The sonographic findings were correlated

  14. Papel da ultra-sonografia na avaliação da efusão pleural The role of ultrasound in the assessment of pleural effusion

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    Adilson Cunha Ferreira

    2006-04-01

    Full Text Available A efusão pleural, antigamente denominada derrame pleural, é caracterizada pelo acúmulo de líquido no espaço pleural, em decorrência do desequilíbrio entre formação e reabsorção de fluido ou por alteração na drenagem linfática. O propósito desta revisão foi estabelecer a importância da aplicação da ultra-sonografia no diagnóstico de efusão pleural. Os autores discutem a aplicação da ultra-sonografia no diagnóstico e abordagem terapêutica dessa entidade, e ressaltam sua importância nas doenças do tórax, vantagens, limitações e desvantagens em relação a radiografia simples, tomografia computadorizada e exame físico. Discutem, ainda, o conceito de efusão pleural, sua fisiopatologia, morbidade, mortalidade, principais causas e apresentação clínica. A técnica de realização do exame é sistematicamente abordada, tanto pela via torácica quanto abdominal.The pleural effusion, formerly called pleural spill, is an accumulation of fluid in the pleural space, as a consequence of an imbalance between the formation and reabsorption of such fluid, or due to an alteration in the drainage to lymph nodes. The purpose of this bibliographic review is to establish the importance of the use of ultrasound in pleural diffusion diagnosis. The authors discuss the use of ultrasonography in the diagnosis and therapeutic approach of this disease, and stress the importance of ultrasonography in chest diseases diagnosis, its advantages, limitations and disadvantages when compared to the common x-ray, computed tomography and physical examination. The authors also discuss the definition of pleural effusion, its physiopathology, morbidity, mortality, main causes and clinical presentation. The examination technique is systematically approached both by thoracic and abdominal pathways.

  15. Feasibility of UltraFast Doppler in Post-operative Evaluation of Hepatic Artery in Recipients following Liver Transplantation.

    Science.gov (United States)

    Kim, Se-Young; Kim, Kyoung Won; Choi, Sang Hyun; Kwon, Jae Hyun; Song, Gi-Won; Kwon, Heon-Ju; Yun, Young Ju; Lee, Jeongjin; Lee, Sung-Gyu

    2017-11-01

    To determine the feasibility of using UltraFast Doppler in post-operative evaluation of the hepatic artery (HA) after liver transplantation (LT), we evaluated 283 simultaneous conventional and UltraFast Doppler sessions in 126 recipients over a 2-mo period after LT, using an Aixplorer scanner The Doppler indexes of the HA (peak systolic velocity [PSV], end-diastolic velocity [EDV], resistive index [RI] and systolic acceleration time [SAT]) by retrospective analysis of retrieved waves from UltraFast Doppler clips were compared with those obtained by conventional spectral Doppler. Correlation, performance in diagnosing the pathologic wave, examination time and reproducibility were evaluated. The PSV, EDV, RI and SAT of spectral and UltraFast Doppler measurements exhibited excellent correlation with favorable diagnostic performance. During the bedside examination, the mean time spent for UltraFast clip storing was significantly shorter than that for conventional Doppler US measurements. Both conventional and UltraFast Doppler exhibited good to excellent inter-analysis consistency. In conclusion, compared with conventional spectral Doppler, UltraFast Doppler values correlated excellently and yielded acceptable pathologic wave diagnostic performance with reduced examination time at the bedside and excellent reproducibility. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  16. Acurácia diagnóstica da histerossalpingografia e da ultra-sonografia para avaliação de doenças da cavidade uterina em pacientes com abortamento recorrente Diagnostic accuracy of hysterosalpingography and transvaginal sonography to evaluate uterine cavity diseases in patients with recurrent miscarriage

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    Évelyn Traina

    2004-01-01

    Full Text Available OBJETIVO: avaliar a acurácia da histerossalpingografia e da ultra-sonografia transvaginal bidimensional para o diagnóstico de defeitos uterinos em pacientes com aborto recorrente. MÉTODOS: oitenta pacientes com história de dois ou mais abortos espontâneos consecutivos foram submetidas a histerossalpingografia, ultra-sonografia bidimensional pélvica e transvaginal e histeroscopia ambulatorial. Os achados foram divididos em três grupos: alterações da forma, sinéquias e lesões polipóides. A histeroscopia foi considerada padrão-ouro. A concordância entre os diferentes métodos foi avaliada pelo coeficiente kappa e sua significância foi testada. O nível de significância adotado foi de 0,05 (alfa=5%. Sensibilidade, especificidade, valores preditivos positivo e negativo, com intervalos de confiança de 95%, foram calculados. RESULTADOS: defeitos cavitários foram diagnosticados em 29 (36,3% pacientes, sendo 11 (13,7% alterações da forma, 17 (21,3% sinéquias e uma (1,3% lesão polipóide. A concordância global da histerossalpingografia com a histeroscopia foi de 85,0%, ao passo que da ultra-sonografia foi de apenas 78,7%. Os melhores resultados da histerossalpingografia foram obtidos para os diagnósticos de alterações da forma e sinéquias (acurácia de, respectivamente, 97,5 e 95%. Para lesões polipóides, a histerossalpingografia teve acurácia de apenas 92,5%, devido ao baixo valor preditivo positivo (14,3%. A ultra-sonografia teve acurácia inferior para todos os diagnósticos, 93,7% para alterações da forma e 85% para detecção de sinéquias, às custas principalmente de baixa sensibilidade. CONCLUSÕES: a histerossalpingografia revelou boa acurácia diagnóstica para a pesquisa da cavidade uterina em pacientes com aborto recorrente. A ultra-sonografia mostrou especificidade alta, porém com baixa sensibilidade.PURPOSE: to evaluate the diagnostic accuracy of hysterosalpingography (HSG and transvaginal sonography (TVS in

  17. Relação entre índice de resistência obtido pela ultra-sonografia Doppler transfortanela e o neurodesenvolvimento até o primeiro ano de vida em recém-nascidos a termo com encefalopatia hipóxico-isquêmica leve e moderada Relation between the resistance index obtained by the transfontanellar Doppler ultrasonography and the neurological development until the first year of life in term infants with mild or moderate hypoxic-ischaemic encephalopathy

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    Maria Helena Martins Garcia

    2007-12-01

    Full Text Available OBJETIVO: Avaliar a relação do índice de resistência (IR obtido pela ultra-sonografia Doppler transfontanela com o neurodesenvolvimento até um ano de idade, em recém-nascidos (RN a termo com encefalopatia hipóxica-isquêmica (EHI leve a moderada, secundária à asfixia intra-parto. MÉTODO: Estudo prospectivo em 20 RN com EHI leve a moderada, IR elevado no primeiro exame de Doppler, e sem doenças associadas ou anormalidades morfológicas cerebrais. Foram realizados exames seriados bimensais de Doppler transfontanela a partir do sétimo dia de vida, e avaliações clínicas mensais do neurodesenvolvimento no primeiro ano de vida. RESULTADOS: Houve normalização progressiva dos valores de IR até o último exame realizado. Cinco pacientes apresentaram normalização clínico-neurológica no período neonatal, após o primeiro exame de Doppler. Quinze lactentes apresentaram alterações neurológicas com resolução a partir do segundo trimestre de vida. CONCLUSÃO: Houve relação entre os períodos em que ocorreu a normalização dos valores de IR e a melhora clínica-neurológica.OBJECTIVE: To evaluate the relation between the resistance index (RI obtained by transfontanellar Doppler ultrasonography, and the neurodevelopment until one year of life, at term newborns with mild or moderate hypoxic-ischaemic encephalopathy due to intrapartum asphyxia. METHOD: 20 term newborns, with mild or moderate hypoxic-ischemic encephalopathy, high values of resistance index in the first exam, and without cerebral morfologic abnormalities or other diseases. They were submitted to serial bimonthly transfontanellar Doppler ultrasonography, from the seventh day of life on, and monthly clinical neurodevelopment assessment until one year of life. RESULTS: There was a progressive normalization of RI values until the last examination. In five cases there were clinical neurologic normalization in the neonatal period after the first Doppler exam. Fifteen infants

  18. Achados histeroscópicos em mulheres na pós-menopausa com diagnóstico de espessamento endometrial por ultra-sonografia transvaginal Hysteroscopic findings in postmenopausal women with endometrial thickening diagnosed by transvaginal ultrasound

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    Adriana Bittencourt Campaner

    2004-02-01

    Full Text Available OBJETIVO: correlacionar espessamento endometrial diagnosticado por ultra-sonografia com os achados histeroscópicos, em mulheres na pós-menopausa. MÉTODOS: foi realizado estudo transversal com avaliação histeroscópica em 121 mulheres na pós-menopausa, com diagnóstico de espessamento do endométrio por ultra-sonografia transvaginal. Das pacientes incluídas, 23 (19% recebiam diferentes esquemas de hormonioterapia e 98 não referiam uso de reposição hormnonal.; 55 pacientes queixavam-se de sangramento por via vaginal e as restantes apresentavam-se sem esta condição. Os exames endoscópicos foram realizados ambulatorialmente, utilizando-se histeroscópio rígido de 4 mm. Para a distensão da cavidade uterina empregou-se gás carbônico (CO2. Biópsia foi praticada em todas as pacientes, com auxílio de cureta tipo Novak, de 3 mm, e o material obtido submetido a estudo histopatológico. RESULTADOS: a espessura do endométrio variou entre 6 e 38 mm, com média de 10,7 ± 5,3 mm. Os achados histeroscópicos foram: lesão polipóide, em 51 pacientes (42,1%; endométrio atrófico, em 15 (12,4%; sinéquia senil, em 15 (12,4%; espessamento focal, em 13 (10,7%; lesão cerebróide, em 6 (5,0%; endométrio proliferativo, em 5 (4,1%; muco, em 5 (4,1%; mioma, em 4 (3,3%; endométrio secretor, em 3 (2,5%; hiperplasia endometrial, em 3 (2,5% e atrofia cística, em 1 (0,8%. Observou-se correlação entre os achados histeroscópicos e os resultados da histopatologia em 30 dos 51 casos de pólipo, em 12 dos 15 de endométrio atrófico e na totalidade dos casos sugestivos de hiperplasia endometrial e de adenocarcinoma. CONCLUSÃO: na maioria das pacientes, o exame histeroscópico revelou que não se tratava de real espessamento endometrial, mas sim de outras variedades de lesão da cavidade uterina.PURPOSE: to correlate endometrial thickening diagnosed by ultrasonography with hysteroscopic findings in postmenopausal women. METHODS: a transversal study

  19. Uso da ultra-sonografia na triagem de disrafismos espinhais ocultos Screening of occult spinal dysraphism by ultrasonography

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    José Gilberto de Brito Henriques

    2004-09-01

    Full Text Available O uso da ultra-sonografia para diagnóstico de lesões da coluna vertebral é difundido desde a década de oitenta. Suas aplicações envolvem: diagnóstico de lesões medulares traumáticas; uso intra-operatório em cirurgias do trauma e tumores medulares; uso pré-operatório e evolutivo em pacientes com disrafismos espinhais; diagnóstico pré-natal dos disrafismos; diagnóstico dos disrafismos espinhais ocultos ao nascimento. Pacientes com suspeita de disrafismo espinhal oculto (estigmas cutâneos em linha média ou história familiar de disrafismos representaram a principal indicação do exame que foi realizado em 292 pacientes do Hospital das Clínicas da Universidade Federal de Minas Gerais. Alterações como lipomas do cone medular, medula baixa, filo terminal espesso, cistos da ponta do cone medular e seios dérmicos foram identificados com fidelidade à ultra-sonografia. A interpretação do exame não apresentou dificuldades técnicas. Sua realização é rápida, não é necessária sedação, apresenta baixo custo e idealmente deve ser realizado pelo próprio neurocirurgião devido ao grande número de informações possíveis durante o exame. O exame entretanto não substitui a ressonância magnética mas pode ser um bom método de triagem para os pacientes.Ultrasonography for diagnosis of spinal cord diseases has been used since the eighties. There are different fields for its use: traumatic spine lesions, intra-operative use in trauma and spine tumors surgery, pre-operative and follow up study for spinal dysraphism, occult spinal dysraphism of the newborn. Patients with suspected occult spinal dysraphism are the most important indication for the method. Utrasonography was performed in 292 patients of Hospital das Clínicas, Universidade Federal de Minas Gerais. Lesions such as conus medullaris lipomas, low level of conus medullaris, filum terminale tethering, cauda equina cysts and dermal sinuses can be well demonstrated. There

  20. Ultrasonography as a predicting tool for carcass traits of young bulls Ultra-sonografia para predição das características da carcaça de bovinos jovens em confinamento

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    Liliane Suguisawa

    2003-12-01

    Full Text Available Considerable resources have been allocated to support research in the development of non-invasive and non-destructive techniques for carcass composition and quality evaluation. Ultrasonography is a reliable and relatively low-cost technique that can be used. In the present study, real-time ultrasonography was used to predict ribeye area (REA and subcutaneous fat thickness (FT in live animals as compared to carcass measurements. Animals used were 115 yearling bull calves (initial body weight, 329 kg, kept under feedlot conditions, of four genetic groups (30, ½ Angus x Nellore; 30, ½ Canchim x Nellore; 30, ½ Simmental x Nellore, and 25 Nellore, and two finishing frame sizes (small and large. Four ultrasonographic measurements were taken every 28 days until slaughter. Predictive precision of ultrasonographic measurements increased as animals approached slaughter, reaching maximum values at the last measurement (R²=0.68 and 0.82 for REA and FT, respectively. FT carcass measurements was influenced by genetic group and live measurements (P O desenvolvimento de técnicas não invasivas e não destrutivas para a avaliação da composição e qualidade de carcaça em animais tem mobilizado consideráveis recursos em pesquisa. A ultra-sonografia aparece neste contexto como uma técnica viável, confiável e de custo aceitável para esta função. No presente trabalho foi avaliada a técnica de ultra-sonografia em tempo real como ferramenta para predição da área de olho-de-lombo (AOL e espessura da camada de gordura subcutânea (ECG a partir de imagens tomadas em animais vivos, quando comparadas com as medições na carcaça. Foram utilizados 115 bovinos jovens (30, ½ Angus x Nellore; 30, ½ Canchim x Nellore; 30, ½ Simental x Nellore, e 25 Nellores, com peso inicial médio de 329 kg e de dois tamanhos à maturidade (pequeno e grande, no sistema de produção do novilho superprecoce. As medidas de ultra-sonografia foram realizadas a cada 28 dias

  1. Diagnóstico de cistos ovarianos pela palpação de ultra-sonografia transretal em fêmeas suínas: relato de dois casos clínicos

    OpenAIRE

    VIANA, Carlos Henrique Cabral; ARRUDA, Rubens Paes de; MORETTI, Anibal Saint'Anna; VISINTIN, José Antonio

    1998-01-01

    Foram abordados alguns conceitos sobre a fisiopatologia e a semiologia de cistos ovarianos em fêmeas suínas, descrevendo-se dois casos clínicos, um sintomático e outro assintomático. No caso sintomático, observou-se infertilidade, cios irregulares, edema de vulva e clitóris aumentado de volume. À palpação retal, constataram-se cistos em ambos os ovários da fêmea com sintomas e um cisto no ovário esquerdo da assintomática. A ultra-sonografia possibilitou visualizar, assim como avaliar com prec...

  2. Rastreamento Pré-natal de Anormalidades Cardíacas: Papel da Ultra–sonografia Obstétrica de Rotina renatal Screening of Cardiac Abnormalities: The Role of Routine Obstetrical Ultrasound

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    Tzvi Bacaltchuk

    2001-10-01

    Full Text Available Objetivo: avaliar o papel da ultra-sonografia obstétrica de rotina no rastreamento pré-natal de cardiopatias congênitas ou arritmias graves e os fatores envolvidos na sua acurácia. Métodos: a amostra foi constituída de 77 neonatos ou lactentes internados no Instituto de Cardiologia do Rio Grande do Sul no período de maio a outubro de 2000, com diagnóstico pós-natal confirmado de cardiopatia estrutural ou arritmia grave, que tinham sido submetidos, durante a vida fetal, a pelo menos uma ultra-sonografia obstétrica após a 18ª semana de gestação. Após consentimento informado, um questionário padronizado foi aplicado. As variáveis categóricas (tipo de cardiopatia e a acessibilidade ecográfica para o diagnóstico, alteração do ritmo cardíaco, número de gestações, paridade, abortamentos prévios, estado civil das gestantes, tipo de parto, área de internação hospitalar, sexo, tipo de serviço onde foi realizado o pré-natal, indicação da ultra-sonografia obstétrica, número de ultra-sonografias realizadas, tipo de serviço onde foi realizada a ultra-sonografia obstétrica, local onde foi realizada a ultra-sonografia obstétrica, renda familiar, escolaridade materna e escolaridade paterna foram comparadas pelo teste do chi² ou pelo teste exato de Fisher e um modelo de regressão logística foi utilizado para determinar variáveis independentes eventualmente envolvidas na suspeita pré-natal de cardiopatia. Resultados: em 19 pacientes (24,7%, a ultra-sonografia obstétrica foi capaz de levantar suspeita de anormalidades estruturais ou de arritmias. Ao serem consideradas apenas as cardiopatias congênitas, esta taxa foi de 19,2% (14/73. Em 73,7% dos pacientes com suspeita de anormalidades cardíacas durante a ultra-sonografia obstétrica, as cardiopatias suspeitadas eram acessíveis ao corte de 4 câmaras isolado. Observou-se que 26,3% das crianças com suspeita pré-natal de cardiopatia apresentaram arritmias durante o

  3. Velocimetria Doppler no período neonatal em recém-nascidos a termo pequenos para idade gestacional Neonatal Doppler velocimetry in full term small-for-gestational age newborns

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    Iracema Augusta Carvalho Cortez Muniz

    2003-09-01

    Full Text Available Este estudo teve como objetivo avaliar o fluxo sanguíneo cerebral em recém-nascidos a termo pequenos para idade gestacional, utilizando ultra-sonografia Doppler craniana ao nascimento. O estudo foi desenvolvido no CAISM/UNICAMP (Centro de Saúde Terciário para Mulheres. Foram selecionados sessenta recém-nascidos e divididos em 2 grupos: 36 adequados para idade gestacional (AIG e 24 pequenos para idade gestacional (PIG. Foi realizada a avaliação de ultra-sonografia Doppler craniana nos grupos, entre 24-48 horas após o nascimento. A velocidade de fluxo sanguíneo cerebral foi menor no grupo PIG na artéria cerebral anterior (ACA. As medidas Doppler foram estatisticamente diferentes entre os grupos apenas para valores relacionados à velocidade de fluxo de pico sistólico (VFPS e velocidade de fluxo médio (VFM na ACA. Não houve diferenças significantes para nenhum dos parâmetros avaliados de velocidade de fluxo na artéria cerebral média (ACM. Concluiu-se que recém-nascidos PIG apresentaram VFPS e VFM significativamente menores apenas na ACA. A adequação peso/idade gestacional, presença de policitemia neonatal e valores de pressão arterial média estiveram estatisticamente associados a VFM na ACA. A presença de sofrimento fetal, valores de pressão arterial média e hábito de fumar durante a gestação estiveram estatisticamente associados a VFM na ACM.This study aimed to evaluate the cerebral blood flow of full term small-for-gestational age newborns, using cranial ultrasound Doppler at birth. This study was performed at CAISM/UNICAMP (Tertiary Health Center for Women. Sixty term newborns were selected and divided in two groups: appropriate-for-gestational age (AGA (36 neonates and small-for-gestational age (SGA (24 neonates. Cranial ultrasound Doppler evaluation was performed on both groups, between 24 and 48 hours after birth. Cerebral blood flow velocity (CBFV was lower in the small-for-gestational age group, in the anterior

  4. Doppler Processing with Ultra-Wideband (UWB) Radar Revisited

    Science.gov (United States)

    2018-01-01

    REPORT TYPE Technical Note 3. DATES COVERED (From - To) December 2017 4. TITLE AND SUBTITLE Doppler Processing with Ultra-Wideband (UWB) Radar...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT This technical note revisits previous work performed at the US Army Research Laboratory related to...target considered previously is proportional to a delayed version of the transmitted signal, up to a complex constant factor. We write the received

  5. Calcinose peritendínea do tendão calcâneo associada a dermatomiosite: correlação entre radiografia convencional, ultra-sonografia, ressonância magnética e macroscopia cirúrgica

    OpenAIRE

    Rosa,Ana Cláudia Ferreira; Costa,Edegmar Nunes; Machado,Márcio Martins; Rocha,Válney Luiz da; Sernik,Renato Antônio; Nunes,Rodrigo Alvarenga; Lemes,Marcella Stival; Gomide,Lidyane Marques de Paula; Albieri,Alexandre Daher; Santos Júnior,Rubens Carneiro dos; Barros,Nestor de; Cerri,Giovanni Guido

    2006-01-01

    A calcinose intersticial é uma afecção incomum, na qual existe deposição de cálcio localizada ou disseminada na pele, tecido celular subcutâneo, músculos e tendões. Freqüentemente a calcinose está associada com doenças do tecido conjuntivo, como esclerodermia e dermatomiosite. Os autores relatam um caso de calcinose intersticial associada a dermatomiosite, estudada com radiografia convencional, ultra-sonografia, ressonância magnética, e com correlação com a macroscopia cirúrgica....

  6. Calcinose peritendínea do tendão calcâneo associada a dermatomiosite: correlação entre radiografia convencional, ultra-sonografia, ressonância magnética e macroscopia cirúrgica

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    Rosa Ana Cláudia Ferreira

    2006-01-01

    Full Text Available A calcinose intersticial é uma afecção incomum, na qual existe deposição de cálcio localizada ou disseminada na pele, tecido celular subcutâneo, músculos e tendões. Freqüentemente a calcinose está associada com doenças do tecido conjuntivo, como esclerodermia e dermatomiosite. Os autores relatam um caso de calcinose intersticial associada a dermatomiosite, estudada com radiografia convencional, ultra-sonografia, ressonância magnética, e com correlação com a macroscopia cirúrgica.

  7. Medida da espessura do segmento uterino inferior em gestantes com cesárea prévia: análise da reprodutibilidade intra- e interobservador por ultra-sonografia bi- e tridimensional Lower uterine segment thickness measurement in pregnant women with previous caesarean section: intra- and interobserver reliability analysis using bi- and tridimensional ultrasonography

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    Daniela de Abreu Barra

    2008-03-01

    Full Text Available OBJETIVO: comparar a reprodutibilidade intra- e interobservador da medida da espessura total do segmento uterino inferior (SUI, por via abdominal, e da medida da camada muscular, por via vaginal, usando ultra-sonografia bi- e tridimensional. MÉTODOS: foi estudada a medida da espessura do SUI de 30 gestantes com cesárea anterior, entre a 36ª e a 39ª semanas, por dois observadores. Foi efetuada abordagem ultra-sonográfica abdominal com a paciente em posição supina e vaginal em posição de litotomia. No corte sagital, foi identificado SUI e foram coletadas quatro imagens bidimensionais e dois blocos tridimensionais da espessura total por via abdominal e o mesmo da camada muscular por via vaginal. As aquisições tridimensionais foram manipuladas no modo multiplanar. O tempo foi cronometrado. A reprodutibilidade foi avaliada pelo cálculo da diferença absoluta entre todas as medidas, proporção de diferenças menores que 1 mm, coeficiente de correlação intraclasse (ICC e limites de concordância de Bland e Altman. RESULTADOS: a medida da espessura média do SUI por via abdominal bidimensional foi de 7,4 mm e, por via vaginal, de 2,7 mm; a tridimensional foi 6,9 mm abdominal e 5,1 mm vaginal. Reprodutibilidade intra- e interobservador da via vaginal versus abdominal: menor diferença absoluta (0,2-0,4 versus 0,8-1,5 mm, maior proporção de diferenças (85,8-97,8 versus 48,7-72,8% com p0,05 e menores limites de concordância (-3,8 a 3,4 versus -3,6 a 4 mm para ultra-sonografia tridimensional e ICC semelhantes (0,6-0,9 versus 0,7-0,9. CONCLUSÕES: do exposto, concluímos que a medida da espessura da camada muscular do SUI por via vaginal utilizando a ultra-sonogafia tridimensional é mais reprodutível. Nossos resultados, porém, não indicam que essa medida tenha implicação clínica para predição de rotura uterina, que não foi objeto deste estudo. O único trabalho que correlacionou a espessura do SUI com risco de rotura uterina, sem

  8. Hipertensão portal por esquistossomose mansônica hepatoesplênica: efeito da desconexão ázigo-portal com esplenectomia no diâmetro e na velocidade média de fluxo do sistema portal (estudo ultra-sonográfico com Doppler Hepatosplenic schistosomotic portal hypertension: effect of esophagogastric devascularization with splenectomy on the diameter and mean flow velocity in the portal system (ultra-sonographic Doppler study

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    Azzo WIDMAN

    2001-01-01

    Full Text Available Racional - A esplenectomia com desconexão ázigo-portal tem sido indicada para o tratamento da hemorragia digestiva pelas varizes esofágicas na hipertensão portal da esquistossomose mansônica hepatoesplênica. Todavia, esta técnica terapêutica apresenta índices variáveis de complicações trombóticas precoces do sistema portal (13,3% a 53,2%. Supondo que as alterações circulatórias devidas ao tratamento cirúrgico tenham papel preponderante neste acontecimento, procurou-se identificar elementos hemodinâmicos que, dentre os múltiplos fatores causais, tenham facilitado a ocorrência desta complicação. Com este intuito estudou-se comparativamente, mediante ultra-sonografia com Doppler, o sistema portal de dois grupos de pacientes em condições clínicas semelhantes: não-operados e com desconexão ázigo-portal em fase pós-operatória tardia (período superior a 6 meses. Casuística/Método - Foram estudados 58 pacientes com esquistossomose mansônica hepatoesplênica e com antecedentes de hemorragia digestiva alta, divididos em dois grupos: A (29 sob controle ambulatorial: clínico e endoscópico; B (29 submetidos previamente a desconexão ázigo-portal. Em todos foi feita a medida do diâmetro e da velocidade média de fluxo do sangue na veia porta e seus ramos direito e esquerdo, mediante ultra-sonografia com Doppler. Os resultados foram submetidos a análise univariada inter e intragrupo. Resultados - No grupo A (não-operados: a veia porta apresentou diâmetro maior do que o dos ramos direito e esquerdo e nestes esta medida foi semelhante (10,6 ± 2,9, 8,0 ± 1,8, 9,1 ± 2,6 cm; a velocidade média de fluxo na veia porta e nos ramos portais foi semelhante (15,62 ± 6,17, 14,92 ± 5,33, 16,12 ± 4,18 cm/seg. No grupo B (operados: houve diminuição de ambos os parâmetros na veia porta e seus ramos (8,8 ± 1,7, 5,2 ± 1,2, 7,5 ± 2,2 cm/12,53 ± 2,60, 8,86 ± 1,75, 9,60 ± 3,75 cm/seg. Conclusões - Houve redu

  9. Importância da ultra-sonografia anorretal tridimensional na decisão terapêutica da endometriose profunda Importance of the three-dimensional anorectal ultrasonography in deep endometriosis

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    Univaldo Etsuo Sagae

    2009-12-01

    Full Text Available OBJETIVO: Este estudo visa demonstrar a importância da ultra-sonografia anorretal tridimensional (US 3D no diagnóstico da endometriose profunda e o grau de acometimento do trato intestinal na decisão terapêutica da endometriose do septo retovaginal. MÉTODOS: Estudo prospectivo realizado entre março de 2007 e julho de 2009. Sessenta e cinco mulheres com endometriose pélvica e com queixas gastrointestinais foram avaliadas e submetidas a US 3D. Vinte pacientes, média de idade 33,7anos, com suspeita de foco endometriótico intestinal foram submetidas ao procedimento laparoscópico para a realização de inventário da cavidade abdominal e tratamento cirúrgico. RESULTADOS: Em dezenove mulheres (95%, os achados laparoscópicos confirmaram a presença do foco endometriótico retal. O procedimento realizado à laparoscopia foi: exérese de foco peritoneais (n= 1; ressecção parcial do retossigmóide (n= 9; exérese de nódulo de reto (n= 10. O tempo operatório médio por procedimento foi de 120 minutos. O tempo médio de alta foi 1,7 dias. Duas pacientes apresentaram como complicação o aparecimento de fistula retovaginal. CONCLUSÃO: Conclui-se que a ultra-sonografia anorretal tridimensional é exame específico na avaliação do segmento anorretal, decisivo na detecção de focos endometrióticos do septo retovaginal e avalia eventuais doenças associadas nesse segmento, determinando a estratégica terapêutico-cirúrgica adequada.OBJECTIVE: This study aims to demonstrate the importance of three-dimensional anorectal ultrasonography (US 3D in the diagnosis of deep endometriosis and level of intestinal involvement in the decision of the therapy of endometriosis of rectovaginal septum. METHODS: A prospective study between March 2007 and July 2009. Sixty-five women with pelvic endometriosis and gastrointestinal complaints were evaluated and submitted to 3D U.S.. Twenty patients, mean age 33.7 years, with suspected of intestinal endometriosis

  10. Evolução do comprimento cervical uterino na gestação, avaliado pela ultra-sonografia transvaginal Changes in cervical length during pregnancy measured by transvaginal ultrasound

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    Reginaldo Antônio de Oliveira Freitas-Júnior

    2003-03-01

    Full Text Available OBJETIVO: analisar a evolução do comprimento cervical uterino, ao longo da gestação, avaliado por meio da ultra-sonografia transvaginal. MÉTODOS: foi realizado estudo prospectivo, longitudinal, no qual 82 gestantes hígidas foram acompanhadas desde o início da gestação, das quais 49 mantiveram o seguimento até o parto sem complicações da gravidez, sendo examinadas a cada quatro semanas, e agrupadas, conforme a paridade, em nulíparas ou com um ou mais partos anteriores. O comprimento do colo uterino foi avaliado em vista sagital pela ultra-sonografia transvaginal, com a medida linear da distância entre os orifícios cervicais interno e externo. RESULTADOS: as médias de comprimento do colo uterino, bem como os percentis 5, 25, 50, 75 e 95, em função da idade gestacional, não diferiram significativamente entre os grupos estudados (p>0.05. No intervalo entre a 20ª e a 24ª semana gestacional o comprimento cervical variou entre 28, 35 e 47,2 mm, com os percentis 5, 50 e 95, respectivamente. O comprimento cervical uterino diminuiu progressivamente ao longo da gestação normal, sendo esse encurtamento significativo após a 20ª semana de gravidez e mais expressivo após a 28ª semana (pPURPOSE: to establish a normality curve of cervical length during pregnancy measured by transvaginal ultrasonography. METHODS: we conducted a prospective, longitudinal study on 82 healthy pregnant women who were followed up from the beginning of pregnancy to delivery at four-week intervals, of whom 49 concluded the study. Patients were divided according to parity into nulliparous women and women with one or more previous deliveries. Cervical length was measured in a sagittal view by transvaginal ultrasonography, as the linear distance between internal and external cervical os. RESULTS: no significant difference was observed in mean cervical length or the 5th, 25, 50th, 75th, or 95th percentile according to gestational age between groups (p>0

  11. PARÂMETROS REPRODUTIVOS DE MATRIZES SUÍNAS INSEMINADAS COM SÊMEN DILUÍDO EM ÁGUA DE COCO APÓS MONITORAMENTO ULTRA-SONOGRÁFICO TRANSCUTÂNEO

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    Pierre Castro Soares

    2006-10-01

    Full Text Available Com o objetivo de avaliar o efeito de diluidores de sêmen (MERK III, BTS e água de coco acrescida de citrato de sódio a 5% sobre parâmetros reprodutivos de matrizes suínas, utilizou-se sêmen diluído nas concentrações de 4x109 e 8x109 espermatozóides/100ml na inseminação artificial de 173 fêmeas púberes e 184 adultas, com prévio monitoramento ultra-sonográfico do estro e ovulação. O diagnóstico de gestação também foi realizado por ultra-sonografia transcutânea. Os dados revelaram altas percentagens (89,5% a 95,6% de prenhes das matrizes suínas púberes e adultas, sem variação significativa entre os tipos de diluidores utilizados. Sugere-se, portanto, que a água de coco in natura pode ser utilizada na diluição de sêmen suíno, significando uma alternativa de baixo custo, e que monitoramento ultra-sonográfico transcutâneo constitui um método auxiliar no diagnóstico de estro, ovulação e prenhez. PALAVRAS-CHAVE: Suíno, sêmen, água de coco, MERK III, BTS, ultra-sonografia.

  12. Acurácia diagnóstica do espessamento ecogênico periportal à ultra-sonografia e da histopatologia no diagnóstico diferencial da atresia biliar Accuracy of echogenic periportal enlargement image in ultrasonographic exams and histopathology in differential diagnosis of biliary atresia

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    Mariza L. V. Roquete

    2008-08-01

    Full Text Available OBJETIVOS: Definir a sensibilidade, especificidade e a acurácia do espessamento ecogênico periportal à ultra-sonografia e da histopatologia hepática, isolados ou em conjunto, na distinção diagnóstica entre atresia biliar e as colestases intra-hepáticas. MÉTODOS: Trata-se de estudo retrospectivo realizado entre janeiro de 1990 e dezembro de 2004. Foram analisados 51 casos de atresia biliar e 45 com colestase intra-hepática. A histopatologia foi realizada por uma patologista de forma cega. O espessamento ecogênico periportal foi pesquisado na ultra-sonografia como único sinal diagnóstico de atresia biliar. Foram calculados os índices de sensibilidade, especificidade e acurácia do espessamento ecogênico periportal e da histologia isoladamente ou associados. O padrão-ouro utilizado para o diagnóstico de atresia biliar foi o aspecto da via biliar extra-hepática à laparotomia. RESULTADOS: O espessamento ecogênico periportal revelou sensibilidade de 49%, especificidade de 100% e acurácia de 72,5%. A histopatologia compatível com obstrução biliar extra-hepática conferiu sensibilidade de 90,2%, especificidade de 84,6% e acurácia de 87,8%. O espessamento ecogênico periportal e a histopatologia isolados ou associados proporcionaram sensibilidade de 93,2%, especificidade de 85,7% e acurácia de 90,3%. CONCLUSÕES: A evidência do espessamento ecogênico periportal na ultra-sonografia é indicação de laparotomia. Se o espessamento ecogênico periportal é negativo, está indicada a biopsia hepática; se a histopatologia revelar sinais de atresia biliar, impõe-se a laparotomia exploradora. Nos casos de espessamento ecogênico periportal negativo com histopatologia de hepatite neonatal ou de outras colestases intra-hepáticas, recomenda-se o acompanhamento ou o tratamento clínico conforme o diagnóstico.OBJECTIVES: To define the sensitivity, specificity and accuracy of the ultrasound triangular cord sign and hepatic

  13. Importância da ultra-sonografia ocular na avaliação pré-operatória de pacientes com catarata total The importance of ocular ultrasonography in the preoperative evaluation of patients with mature cataract

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    Álvaro Pedroso de Carvalho Lupinacci

    2004-02-01

    Full Text Available Com os avanços da cirurgia para catarata, o prognóstico da recuperação da visão aumentou drasticamente, tornando-se necessário prever resultados indesejados para a acuidade visual no pós-operatório. OBJETIVOS: Verificar a importância da ultra-sonografia ocular na avaliação pré-operatória do segmento posterior em pacientes com catarata madura, e relacionar possíveis doenças que possam comprometer os resultados cirúrgicos, sua prevalência e seus principais fatores de risco. MÉTODOS: Foi realizado estudo retrospectivo do prontuário de 262 pacientes em que houve a necessidade de ultra-sonografia ocular devido à presença de catarata madura, impedindo assim a avaliação fundoscópica do segmento posterior. Também foi avaliada a relação entre a presença dessas alterações e o sexo, idade, raça, história de trauma ocular, doenças sistêmicas e oculares e presença de catarata no olho contralateral. RESULTADOS: Encontraram-se alterações ecográficas em 24,8% dos exames realizados entre 1996 e 2001, dos quais o descolamento de retina (9,9% e as condensações vítreas (9,9% foram as mais comuns. CONCLUSÕES: Dentre os fatores de risco levantados como predisponentes para achados de ultra-sonografia ocular, a uveíte foi o único elemento estatisticamente significante. Não foi possível, pelos dados obtidos, correlacionar positivamente o trauma ocu-lar às patologias de segmento posterior descritas.With the new techniques of cataract surgery visual success has increased and it became necessary to foresee undesirable postoperative results regarding visual acuity. PURPOSE: To verify the role of ocular ultrasonography in the preoperative evaluation of patients with mature cataract searching for pos terior segment pathologies that may affect surgical results, their prevalence and the main associated risk factors. METHODS: A retrospective study was performed analyzing records of 262 patients indicated for ocular ultrasonography

  14. Ultra-sonografia na artrite reumatóide: aplicabilidade e perspectivas Ultrasonography in rheumatoid arthritis: applicability and expectations

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    Eloy de Ávila Fernandes

    2008-02-01

    Full Text Available Este trabalho realiza uma revisão bibliográfica sobre o papel do ultra-som (US no diagnóstico precoce da artrite reumatóide (AR, sua utilização no tratamento destes pacientes e sua utilidade na avaliação da resposta ao tratamento. A AR é uma doença inflamatória crônica que, quando não diagnosticada e tratada adequadamente, pode levar à deformidade física e à incapacidade para o trabalho. A introdução precoce das drogas modificadoras da doença (DMCD, sejam elas tradicionais ou mais novas (agentes biológicos, pode modificar a evolução da doença. Para tanto, o diagnóstico da AR precisa ser feito o mais rápido possível. O US é um método que possibilita o estudo das articulações e pode mostrar sinais de atividade inflamatória, especialmente a sinovite. Técnicas como o estudo com Doppler colorido e o Doppler de amplitude podem ajudar na avaliação de atividade da doença, diferenciando tecido inflamatório ativo (pannus de inativo. Outros achados como erosões, alterações tendíneas, bursites, cistos sinoviais e derrames articulares também podem ser encontrados. Esta revisão, no entanto, demonstra que métodos de quantificação da atividade inflamatória ainda precisam ser estabelecidos no US.This review discusses the usefulness of ultrasound in the early diagnosis of reumathoid arthritis, its utilization in these patients treatment and its utility in evaluation of the response to treatment. Reumathoid arthritis is a chronic disease that when it is not promptly diagnosed it can cause physical deformity and disability to work. The early introduction of disease modifying antirheumatic drugs (DMARDs, no matter traditional or newer (biologic agents, may modify the disease outcome. In order that , the diagnosis of RA must be made as soon as possible. Ultrasound makes possible to study the joints and can show signs of inflammatory activity, especially synovitis. Color Doppler and power Doppler can help differentiate

  15. Índice de congestão portal e a ocorrência de trombose portal pós-dape Portal congestion and thrombosis after EDS

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    Fabio Gonçalves Ferreira

    2005-08-01

    Full Text Available OBJETIVO: Comparar os dados obtidos pela ultra-sonografia com doppler no pré-operatório de esquistossomóticos submetidos à desconexão ázigo-portal com esplenectomia (DAPE, calculando o índice de congestão portal, e sua correlação com a trombose portal no pós-operatório. MÉTODOS: Foram estudados 65 pacientes submetidos à DAPE por hipertensão portal esquistossomótica com antecedente de hemorragia digestiva, divididos em dois grupos: Grupo A (28 pacientes que não desenvolveram trombose portal pós-operatória e Grupo B (37 pacientes com trombose portal no pós-operatório. Analisaram-se através de ultra-sonografia com doppler no pré-operatório os seguintes parâmetros da veia porta: diâmetro, área, velocidade média de fluxo do sangue, fluxo de sangue, e estabeleceu-se o índice de congestão portal. RESULTADOS: O diâmetro, área e o fluxo da veia porta foram maiores no grupo B (média de 1,52 cm; 1,77 cm² e 2533,12 ml/min em relação ao grupo A (média de 1,33 cm; 1,44 cm² e 1609,03 ml/min com p = 0,03; 0,03 e 0,04 respectivamente. O índice de congestão portal não foi estatisticamente significativo na comparação dos dois grupos (p = 0,07. CONCLUSÃO: O índice de congestão portal obtido no pré-operatório através da ultra-sonografia com doppler não se mostrou preditivo de trombose portal no pós-operatório dos doentes estudados.BACKGROUND: The study compared the preoperative portal vein congestion index estimated by Doppler ultrasound and the postoperative portal vein thrombosis of patients submitted to esophagogastric devascularization and splenectomy (EDS. METHODS: 65 patients with portal hypertension due to schistosomiasis and previous gastrointestinal bleeding submitted to EDS were divided into two groups: GROUP A (28 patients without postoperative portal vein thrombosis and GROUP B (37 patients with postoperative portal vein thrombosis. The following parameters of preoperative Doppler ultrasound of the

  16. Carcass traits of surubim (“Pseudoplatystoma” spp. evaluated by ultrasound Rendimento de carcaça em surubim ("Pseudoplatystoma" spp. avaliado por ultra-som

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    Daniela Chemim Melo

    2008-12-01

    Full Text Available The parameters of carcass trait of alive surubim (Pseudoplatystoma spp. evaluated by ultrasound were estimated in this trial. A total of 34 fish was divided into two groups according to average body weight: group 1 = 2.7 kg e group 2 = 1.5 kg. The fish were measured for total, head and standard lengths. Ultrasound images of four defined points were obtained: 1 - anterior insertion of dorsal fin; 2 - posterior insertion of dorsal fin; 3 - anterior insertion of fat fin and 4 - insertion of caudal fin. After, weights of carcass, head, shank fillet and belly fillet were obtained. Correlations of measures obtained by the ultrasound images with carcass yield traits were determined. The point 3 showed the best correlations for yield of group 1 with: carcass (0.91, head (0.86, shank fillet (0.87 and belly fillet (0.91. Carcass yield of group 1 was higher (70.9% than group 2 (66.9%, probably due to the highest head weight of these animals. The best equations for carcass yield and fillet weight were the ones that considered the measures of point 3 and total length, respectively. Ultrasound for evaluation of carcass traits in alive surubim is a reliable technique, once it can maintains reproducers with great performance inside stock.Objetivou-se com este trabalho definir parâmetros de avaliação do rendimento de carcaça em surubins Pseudoplatystoma spp. vivos por intermédio da ultra-sonografia. Foram utilizados 34 peixes divididos em dois grupos conforme peso médio: grupo 1 = 2,7 kg e grupo 2 = 1,5 kg. De cada exemplar obtiveram-se as medidas de comprimento total, comprimento de cabeça e comprimento padrão. Foram realizadas imagens dorso ventrais em quatro pontos: 1 - base anterior da nadadeira dorsal; 2 - base posterior da nadadeira dorsal; 3 - base anterior da nadadeira adiposa e 4 - base do pedúnculo caudal, onde foram mensuradas altura, largura e área da musculatura epi-axial. Posteriormente, foram obtidos pesos da carcaça, da cabeça, do fil

  17. Doppler-musical instrument

    International Nuclear Information System (INIS)

    Sato, T.J.; Watanabe, N.

    2001-01-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 μeV, even when the ultra-high energy resolution of ΔE∼0.03 μeV is attained. (author)

  18. Doppler-musical instrument

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T.J. [National Research Institute for Metals, Tsukuba, Ibaraki (Japan); Watanabe, N. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Shibata, K. [Institute for Materials Research, Tohoku Univ., Sendai, Miyagi (Japan)

    2001-03-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 {mu}eV, even when the ultra-high energy resolution of {delta}E{approx}0.03 {mu}eV is attained. (author)

  19. Concentração de progesterona e de estradiol 17-b e características ultra-sonográficas da vesícula embrionária no início da gestação em éguas Puro Sangue Inglês

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    Ferraz L.E.S.

    2001-01-01

    Full Text Available Associaram-se dosagens séricas de progesterona e estradiol 17-beta, realizadas durante os primeiros 36 dias de prenhez em 30 éguas PSI, com exames ultra-sonográficos, para verificar fenômenos que ocorrem com a vesícula embrionária. As éguas foram divididas em dois grupos de 15 animais, o primeiro constituído por éguas paridas e o segundo por éguas virgens ou vazias na estação anterior. Por meio da ultra-sonografia foram verificados fenômenos de mobilidade, fixação e orientação da vesícula embrionária. As concentrações séricas de progesterona e estradiol 17-B variaram (P<0,01 durante o período estudado porém não foi possível estabelecer uma correlação entre concentrações desses hormônios com desenvolvimento da vesícula embrionária. A concentração de estradiol 17-betacirculante foi maior (P<0,01 nas éguas paridas.

  20. Validação da curva normal de peso fetal estimado pela ultra-sonografia para o diagnóstico do peso neonatal Validity of the normal fetal weight curve estimated by ultrasound for diagnosis of neonatal weight

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    José Guilherme Cecatti

    2003-02-01

    Full Text Available OBJETIVO: avaliar a concordância entre o peso fetal estimado (PFE por ultra-sonografia e o neonatal, o desempenho da curva normal de PFE por idade gestacional no diagnóstico de desvios do peso fetal/neonatal e fatores associados. MÉTODOS: participaram do estudo 186 grávidas atendidas de novembro de 1998 a janeiro de 2000, com avaliação ultra-sonográfica até 3 dias antes do parto, determinação do PFE e do índice de líquido amniótico e parto na instituição. O PFE foi calculado e classificado de acordo com a curva de valores normais de PFE em: pequeno para a idade gestacional (PIG, adequado para a idade gestacional (AIG e grande para a idade gestacional (GIG. A mesma classificação foi feita para o peso neonatal. A variabilidade das medidas e o grau de correlação linear entre o PFE e o peso neonatal foram calculados, bem como a sensibilidade, especificidade e valores preditivos para o uso da curva de valores normais de PFE para o diagnóstico dos desvios do peso neonatal. RESULTADOS: diferença entre o PFE e o peso neonatal variou entre -540 e +594 g, com média de +47,1 g, e as duas medidas apresentaram um coeficiente de correlação linear de 0,94. A curva normal de PFE teve sensibilidade de 100% e especificidade de 90,5% em detectar PIG ao nascimento, e de 94,4 e 92,8%, respectivamente, em detectar GIG, porém os valores preditivos positivos foram baixos para ambos. CONCLUSÕES: a estimativa ultra-sonográfica do peso fetal foi concordante com o peso neonatal, superestimando-o em apenas cerca de 47 g e a curva do PFE teve bom desempenho no rastreamento diagnóstico de recém-nascidos PIG e GIG.PURPOSE: tocompare the ultrasound estimation of fetal weight (EFW with neonatal weight and to evaluate the performance of the normal EFW curve according to gestational age for the diagnosis of fetal/neonatal weight deviation and associated factors. METHODS: one hundred and eighty-six pregnant women who delivered at the institution from

  1. Ultra-sonografia do fígado, aparelho renal e reprodutivo da jibóia (Boa constrictor Ultrasonography of the liver, renal and reproductive apparatus of Boa constrictor Snake

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    Francisco C. P. Neto

    2009-04-01

    Full Text Available Atualmente os animais silvestres têm despertado o interesse particular na criação domestica. Na medicina de animais selvagens, os exames ultra-sonográficos podem ser considerados como ferramenta para diagnosticar e prevenir doenças. Deste modo, realizou-se um estudo em 20 jibóias (Boa constrictor, a fim de caracterizar a morfologia e aparência ultra-sonográfica das estruturas presentes da cavidade celomática desses animais. Ultra-sonograficamente, o fígado apresentou-se variando de hipoecóica a levemente hiperecogênica, com margens ecogênicas e ecotextura homogênea em toda sua extensão. Os rins mostraram formato elipsóide, com cápsula fina, regular e hiperecóica. Os folículos ovarianos apresentaram formato ovóide, margens finas, regulares e discretamente hiperecóicas. As estruturas do sistema reprodutor do macho não foram evidenciadas com precisão, devido a sua ecogenicidade similar em relação às estruturas adjacentes e pela presença do "corpo gorduroso" localizado nessa região. A ultra-sonografia da cavidade celomática em jibóias demonstrou ser uma técnica rápida e de fácil acesso, permitindo identificar a morfologia, sintopia e aparência ultra-sonográfica de estruturas como o fígado, rins e de folículos vitelogênicos nas fêmeas.Currently, wild animals have been received special attention for domestic breeding. In Wild Animal Medicine, ultrasonographic exams could be considered as a tool to diagnose and prevent disease. Ultrasonographic examination of twenty snakes (Boa constrictor was performed in order to describe the morphological and ultrasonography appearance of their coelomic structures. Examination by ultrasonography revealed the parechymal liver ranging from slightly hypoechogenic to hyperechogenic, with echogenic margins and homogeneous echotexture in total scanning of this organ. The kidney was accessible for examination by sagittal ultrasound, showing an ellipsoid shape, a hyperechogenic capsule

  2. Mapeamento da safena interna com ecocolor Doppler no pré-operatório de cirurgia de revascularização mioc��rdica

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    BARROS Fanilda Souto

    1999-01-01

    Full Text Available INTRODUÇÃO: O advento do ecocolor Doppler vascular tornou possível informar o estado anatômico e funcional da safena interna ao cirurgião cardiovascular, no pré-operatório da cirurgia de revascularização miocárdica, sem riscos para o paciente ou para o conduto venoso. O objetivo do estudo foi, juntamente com o cirurgião, avaliar a utilidade do mapeamento da safena interna no pré-operatório. CASUÍSTICA E MÉTODOS: Foram estudados, entre março de 1995 e maio de 1998, 208 extremidades inferiores de 104 pacientes selecionados para cirurgia de revascularização miocárdica. O critério utilizado para a seleção da safena foi a safena patente e o diâmetro maior ou igual a 3,0 mm, utilizando os aparelhos de ultra-sonografia ATL - HDI 3000 e Acuson-Sequóia 512. RESULTADOS: Dentre as 208 extremidades estudadas, 186 (89,4% das safenas preenchiam os critérios e a análise do cirurgião estava de acordo com a descrição do ecocolor Doppler. Dezessete (8,2% não preenchiam os critérios e, em 5 (2,4% ,o exame foi compatível com safenectomia radical. Das 17 safenas consideradas não apropriadas, 2 foram exploradas cirurgicamente, sendo a análise do cirurgião concordante com o ultra-som. CONCLUSÃO: Os autores concluem que o ecocolor Doppler, sendo um método diagnóstico não invasivo, pode ser útil no mapeamento da safena interna no pré-operatório de revascularização miocárdica devido à sua capacidade de identificar e selecionar com segurança o vaso a ser utilizado como conduto vascular, o que permite ao cirurgião cardíaco o planejamento cirúrgico.

  3. Prevenção do parto prematuro: emprego do toque vaginal e da ultra-sononografia transvaginal Prevention of preterm birth: use of digital examination and transvaginal ultrasonography

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    Arlete Ayako Yamasaki

    1998-07-01

    Full Text Available Objetivo: avaliar o colo uterino por meio do toque vaginal e da ultra-sonografia transvaginal em gestantes de risco elevado para o parto prematuro. Métodos: durante o período compreendido entre fevereiro de 1995 e setembro de 1997 foram acompanhadas 38 gestantes com elevado risco para o parto prematuro entre a 20ª e 36ª semana de gestação. Estas pacientes foram submetidas semanalmente ao toque vaginal e ao exame ultra-sonográfico transvaginal. O toque vaginal avaliou o colo uterino quanto a dois parâmetros: comprimento e dilatação. A ultra-sonografia transvaginal estudou o comprimento e o diâmetro anteroposterior do colo uterino. Foram analisados os comportamentos destas medidas cervicais ao longo da gestação. Os dois métodos foram comparados quanto à avaliação cervical e à acurácia no diagnóstico do parto prematuro. Resultados: a incidência de partos prematuros foi de 18,4% (7/38. As medidas do comprimento cervical obtidas pela ultra-sonografia foram sempre maiores em relação às medidas obtidas pelo toque vaginal. Mediante análise pelo teste de hipóteses foram observadas uma relação indireta entre o comprimento cervical e a idade gestacional por meio do toque e do estudo ultra-sonográfico (pObjective: to evaluate the uterine cervix by digital and transvaginal ultrasound examinations in pregnant women at high risk of having premature delivery. Methods: during the period between February 1995 and September 1997, 38 pregnant women at high risk of having premature delivery between the 20th and 36th week of gestation were examined. These patients were submitted weekly to both digital and transvaginal ultrasound examinations. The digital examination evaluated the uterine cervix using two parameters: length and dilation. The transvaginal ultrasound studied the length and the anteroposterior diameter of the uterine cervix. The behavior of these cervical measurements was analyzed throughout the pregnancies. The two methods

  4. Medida da velocidade de fluxo nas artérias cerebrais utilizando ultra-som Doppler transfontanela antes e após o tratamento cirúrgico da hidrocefalia

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    ASSIS MARCELO CARDOSO DE

    1999-01-01

    Full Text Available Vinte e sete crianças portadoras de hidrocefalia de diversas etiologias, diagnosticadas pelo exame clínico, neurosonografia e tomografia cerebral computadorizada, foram submetidas a avaliação por ultra-som Doppler (US-Doppler transfontanela para medida da velocidade de fluxo sanguíneo e cálculo do índice de resistência (IR nas artérias cerebrais anteriores, médias e carótidas internas. Todas as crianças foram submetidas a avaliações no pré-operatório e no 1º, 7º, 30º e 60º dias do pós-operatório. Concluímos ser a técnica de neurosonografia e US-Doppler útil no diagnóstico da hidrocefalia, na indicação e controle das derivações liquóricas e no acompanhamento das modificações dos valores do IR comparando-os no pré e pós-operatório imediato e tardio do tratamento cirúrgico da hidrocefalia. Os resultados obtidos permitiram-nos ainda, pela comparação dos valores do IR entre as diversas artérias avaliadas nos diferentes estágios do estudo, concluir serem as artérias cerebrais anteriores representativas das alterações máximas que ocorrem na resistência vascular cerebral em pacientes pediátricos portadores de hidrocefalia.

  5. Bloqueios nervosos guiados por ultra-som Bloqueos nerviosos guiados por ultrasonido Ultrasound-guided nerve blocks

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    Pablo Escovedo Helayel

    2007-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: As técnicas de bloqueios nervosos guiados por ultra-som são baseadas na visualização direta das estruturas nervosas, da agulha de bloqueio e das estruturas anatômicas adjacentes. Desta maneira, é possível depositar a solução de anestésico local precisamente em torno dos nervos e acompanhar a sua dispersão em tempo real, obtendo-se, assim, um bloqueio mais eficaz, de menor latência, menor dependência de referências anatômicas, menor volume de solução anestésica e maior segurança. CONTEÚDO: O artigo revisa os aspectos relativos aos mecanismos físicos para formação de imagens, a anatomia ultra-sonográfica do neuroeixo e dos plexos braquial e lombossacral, os equipamentos e materiais empregados nos bloqueios, os ajustes do aparelho de ultra-som para melhorar as imagens, os planos de visualização das agulhas de bloqueio e as técnicas e o treinamento em bloqueios guiados por ultra-som. CONCLUSÕES: Os passos para se obter sucesso em anestesia regional incluem a identificação exata da posição dos nervos, a localização precisa da agulha, sem lesões nas estruturas adjacentes e, finalmente, a injeção cuidadosa de anestésico local junto aos nervos. Embora a neuroestimulação forneça grande auxílio na identificação dos nervos, esta não consegue, isoladamente, preencher todas essas exigências. Por isso, acredita-se que os bloqueios guiados por ultra-som serão a técnica de eleição para anestesia regional num futuro não muito distante.JUSTIFICATIVA Y OBJETIVOS: Las técnicas de bloqueos nerviosos guiados por ultrasonido se basan en la visualización directa de las estructuras nerviosas, de la aguja de bloqueo y de las estructuras anatómicas adyacentes. De esa manera, se puede depositar la solución de anestésico local precisamente en torno de los nervios y acompañar su dispersión en tiempo real, obteniéndose así, un bloqueo más eficaz, de menor latencia, menor dependencia de

  6. Ultra-sonografia transcraniana em cães com distúrbios neurológicos de origem central Transcranial ultrasonography in dogs with central neurologycal disorders

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    C.F. Carvalho

    2007-12-01

    Full Text Available Avaliaram-se 55 cães com distúrbios neurológicos e verificou-se a ocorrência de afecções neurológicas de origem central, detectadas pela ultra-sonografia transcraniana (USTC. Vinte e nove (52,9% animais apresentaram diagnóstico compatível com hidrocefalia, e destes, 16 (55,1% eram fêmeas e 15 (51,7% tinham menos de dois anos. Quinze (27,3% cães apresentaram lesões focais, quatro (7,2%, alterações difusas e quatro (7,2% apresentavam imagens sugestivas de lissencefalia; em três (5,4% não foram detectadas alterações pela USTC. A hidrocefalia foi o distúrbio neurológico de origem central mais freqüente e a USTC é uma alternativa viável para auxiliar na rotina clínica veterinária como ferramenta diagnóstica na detecção de alterações morfológicas e estruturais do cérebro no cão.In this work, 55 dogs with neurologycal disorder were examined and central neurological affections were detected by transcranial ultrasonography (TCUS. They were classifyed in hydrocephaly, lissencephaly, focal and difuse parenchimal disorders, and none changes. From the examinated dogs, 52.9% presented diagnosis compatible with hydrocephaly, being 55.1% female and 51.7% younger than 2 year-old. Fifteen dogs (27.3% presented focal lesions, 7.2% diffuse lesions, 7.2% images that suggested lissencephaly, and in 5.4% no changes were detected by TCUS. It was concluded that hydrocephaly was the most frequent central neurologycal disorder and TCUS is a valuable alternative to be used in clinical routine as a tool of diagnostic to detect morphological and structural cerebral disorders in dogs.

  7. Ultra-sonografia de características lineares e estimativas do volume de rins de cães Ultrasonographic measurement of linear characteristics and renal volumetry in dogs

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    K.M.O.R. Sampaio

    2002-06-01

    Full Text Available Obtiveram-se as medidas lineares de rins de cães adultos, clinicamente normais, por meio da ultra-sonografia, e estimou-se o volume dos rins de 35 cães (18 fêmeas e 17 machos sem raça definida e com idade entre dois e seis anos. Os animais foram divididos em três grupos de acordo com o peso corporal (3,1 a 10,0 kg; 10,1 a 20,0 kg e 20,1 a 45,0 kg. Os planos de secção sagital, dorsal e transversal foram utilizados para obtenção das medidas lineares de comprimento (C, largura (L e espessura (E. O volume renal foi calculado a partir das medidas lineares utilizando-se a fórmula para o volume de um elipsóide. Os valores médios encontrados para os três grupos foram, respectivamente: comprimento (4,73; 6,09 e 7,13cm, largura (2,81; 3,44 e 3,95cm, espessura (2,43; 3,00 e 3,58cm e volume (17,98; 33,36 e 53,81cm³. As dimensões dos rins esquerdo e direito e de machos e fêmeas foram equivalentes. Observaram-se correlações positivas entre todas as medidas renais e peso corporal.This work aimed to measure by ultrasonography the length, width and depth and to estimate the volume of kidneys of normal adult dogs. Thirty five dogs (18 females and 17 males of mixed breeds, aging from two to six years, were used. The animals were separated in three groups according to their body weights (3.1 to 10.0 kg; 10.1 to 20.0 kg and 20.1 to 45 kg. Sagittal, dorsal and transverse plans of section were used to obtain measures of length, width and depth. The kidney volume was estimated from these measures. Mean values according to the groups were, respectively: 4.73; 6.09 and 7.13cm for length; 2.81; 3.44 and 3.95cm for width; 2.43; 3.00 and 3.58cm for depth; and the estimated volumes were 17.98; 33.36 and 53.81cm³. The length, width, depth and volume of the left and right kidneys were similar, and no difference between male and female was found for these traits. Body weight of animals was positively correlated with all the kidney traits.

  8. Emprego do ultra-som modo B e com efeito Doppler, termômetro infravermelho e medidas antropométricas na avaliação de uma formulação cosmética anticelulítica contendo extrato hidroglicólico de Trichilia catigua e Ptychopetalum olacoides Bentham

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    Idalina Maria Nunes Salgado Reis dos Santos

    2005-01-01

    Hidrolipodistrofia ginóide (H.L.D.G.), a celulite, é comumente tratada com cosméticos contendo extratos vegetais. O estudo realizado foi: ultra-sonografia na avaliação da espessura da hipoderme e a microcirculação cutânea; uso de termômetro infravermelho na medida da temperatura e análise das medidas antropométricas da uma formulação cosmética anticelulítica contendo extrato hidroglicólico de Trichilia catigua e Ptychopetalum olacoides Bentham (catuaba e marapuama). Foram realizadas medidas i...

  9. Ovários policísticos: critérios hemodinâmicos

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    Ávila,Márcio Augusto Pinto de; Murta,Carlos Geraldo Viana

    2001-01-01

    O advento da ultra-sonografia endovaginal de alta resolução abriu novas áreas de pesquisa nos ovários policísticos. O conhecimento da hemodinâmica ovariana é fundamental para o entendimento do comportamento fisiopatológico dos ovários policísticos. Os autores tecem considerações sobre a possibilidade da utilização do Doppler colorido na melhor definição dos ovários policísticos. Os dados sugerem que o aumento da vascularidade e a diminuição da resistência dos vasos do estroma ovariano, assim ...

  10. Relevância da ultra-sonografia dos tendões flexores em cavalos Puro Sangue de corrida na adaptação ao treinamento Significance of flexor tendon ultrasonography in training thoroughbred horses

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    Carolina Roxana Greig

    2005-08-01

    Full Text Available Vinte e quatro potros Puro Sangue de Corrida (PSC, com dois anos de idade foram avaliados ultra-sonograficamente, durante o período final da doma e início de treinamento, através da imagem transversal dos tendões flexor digital superficial (TFDS e profundo (TFDP. As avaliações foram realizadas com intervalos de 15 dias. A área transversal (AT, a textura dos ecos e a ecogenicidade dos tendões foram avaliadas nas sete zonas da região metacarpiana através de um programa de mensuração de imagens do próprio aparelho de ultra-sonografia. Durante a doma e treinamento, houve diminuição da AT na zona IA e IIIA (PThe cross-sectional area (CSA of the superficial digital flexor tendon (SDFT and deep digital flexor tendon (DDFT of twenty four thoroughbreds was ultrasonographically evaluated before and during their initial training to determine the effect of exercise on the tendon CSA, texture and echogenicity to characterize the response to training. Ultrasonographic transverse images of the left forelimb were obtained every fifteen days. The SDFT CSA of zones IA and IIIA showed a decrease (P<0.05, f=0.010 e f=0.023 res. during the breaking and training period and an increase (P< 0.05 of zone IIIC (f=0.039. Evaluating just the training period, SDFT CSA results of zones IA, IIIA and IIIC were similar. The DDFT showed no variation during the breaking phase but when the training phase was evaluated there was a decrease (P<0.05 in zones IA (f=0.006 and IIIA (f=0.006. Evaluating both breaking and training periods the DDFT showed a decrease (P<0.05 in zones IA (f=0.027, IIIA (f=0.0001 and IIIB (f=0.0031. Fiber texture and tendon echogenicity showed no significant difference between breaking and last reading during training. This study provides evidence of variation of adaptation among the ultrasonographic zones of both SDFT and DDFT to exercise during training of thoroughbred horses. Ultra-sonography is not the most indicated method to evaluate the

  11. Classificação ultra-sonográfica do derrame pleural e do empiema parapneumônico Ultrasound classification of pleural effusion and parapneumonic empyema

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    Luís Marcelo Inaco Cirino; Miguel José Francisco Neto; Erasmo Magalhães Castro de Tolosa

    2002-01-01

    Os autores correlacionam as alterações anatomopatológicas da cavidade pleural com os achados ultra-sonográficos no derrame pleural e no empiema parapneumônico e apresentam uma classificação baseada nestes dados. Concluem que a ultra-sonografia é método diagnóstico fidedigno para inferir a fase anatomopatológica da doença pleural, bem como auxiliar na escolha da alternativa de tratamento.We correlated the anatomopathological abnormalities of the pleural space with the ultrasound findings in pa...

  12. Desempenho da ultra-sonografia na detecção das metástases em linfonodos axilares em mulheres com câncer de mama Performance of ultrasound in the detection of axillary lymph node metastases in breast cancer patients

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    Rodrigo Menezes Jales

    2005-09-01

    Full Text Available OBJETIVOS: avaliar o desempenho de diversas características ultra-sonográficas morfológicas (12 e doplervelocimétricas (7, para detecção de metástases linfonodais em mulheres com câncer de mama. MÉTODOS: foram incluídas 179 mulheres (181 axilas, entre janeiro e dezembro de 2004. Os exames ultra-sonográficos foram realizados com transdutor linear em tempo real (Toshiba-Power Vision-6000 (modelo SSA-370A. Para o estudo de parâmetros morfológicos foram utilizadas freqüências entre 7,5 e 12 MHz. Para os parâmetros Doppler foi utilizada freqüência de 5 MHz. Subsequentemente, as pacientes foram submetidas a axilectomia dos níveis I, II e III (158 ou à técnica do linfonodo sentinela (23. Foram calculadas a sensibilidade, a especificidade e os valores preditivos positivo e negativo para cada parâmetro. Para a associação de parâmetros foi utilizada a árvore de decisão. Foram estabelecidos os valores de corte para as variáveis contínuas por meio da curva ROC. RESULTADOS: ao exame ultra-sonográfico foi identificado pelo menos um linfonodo axilar em 173 (96% exames. O exame histológico detectou metástase linfonodal em 87 mulheres (48%. As melhores sensibilidades dos critérios morfológicos foram encontradas com o volume (62%, diâmetro ântero-posterior (62% e local do centro ecogênico (56%. Embora a especificidade da invasão da gordura adjacente (100%, regularidade das margens (92% e da ecotextura do parênquima (99% tenham sido elevadas, a sensibilidade destes parâmetros foi muito baixa. Nenhum critério dopplervelocimétrico alcançou 50% de sensibilidade. A árvore de decisão selecionou a localização do centro ecogênico, a ecotextura do parênquima e a regularidade das margens como melhor associação de parâmetros. CONCLUSÃO: o estadiamento dos linfonodos axilares por método não invasivo ainda é um objetivo não alcançado no tratamento das pacientes com câncer de mama.PURPOSE: to evaluate the role of

  13. Aspectos morfológicos da ultra-sonografia hepática de ovinos Morphologic aspects of hepatic ultrasonography in sheep

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    Pedro B. Néspoli

    2009-04-01

    Full Text Available A ultra-sonografia (US é uma das técnicas de exame complementar eletivas para o diagnóstico de enfermidades hepáticas de diversas espécies domésticas. Em ovinos, no entanto, existem poucos relatos sobre o aspecto ultra-sonográfico de enfermidades hepáticas e não há definição precisa dos padrões anatômicos da US normal do fígado. Neste estudo foram utilizados 58 ovinos da raça Santa Inês: n1=8 machos, n2=10 fêmeas não gestantes e n3=40 fêmeas gestantes. Os animais foram escaneados do 12º ao 8º espaços intercostais (EI para se observar a localização da veia cava caudal (VC, veia porta (VP e vesícula biliar (VB e para se aferir a espessura do fígado sobre a VC e VP no 11º e 10º EI. O fígado foi examinado de forma satisfatória do 12º até o 8º EI. Nesta área, tanto a VC como a VP, foram observadas do 12º ao 9º EI, porém a VC não foi examinada de forma adequada em 11 animais, 10 com peso acima de 50kg. Entre os dois grupos de fêmeas, a VC e a VP foram observadas com maior freqüência no 11º e 10º EI e em todos os machos examinados do 12º ao 10º EI. A localização da vesícula biliar oscilou entre o 10º e o 8º EI, com maior incidência a nível do 9º e 8º EI nas fêmeas gestantes e não gestantes, e sobre o 9º EI nos machos. Comparativamente, a ecogenicidade do parênquima hepático foi mais intensa do que a do córtex renal. Houve correlação significativa entre o peso do fígado e a espessura hepática sobre a veia porta no 11º e o 10º EI no grupo de fêmeas gestantes. A US forneceu informações importantes quanto a topografia e ecogenicidade do fígado e mostrou ser uma ferramenta útil para estimar o peso do órgão.The ultrasonography (US is a complementary technique of choice for the diagnostic of hepatic diseases in many domestics' species. In sheep however there are few reports about ultrasonography in hepatic diseases and there is not precise definition about the anatomic standards of

  14. Uso do ultra-som para punção venosa central em paciente obeso com adenomegalia cervical

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    Jaderson Wollmeister

    2008-08-01

    Full Text Available JUSTIFICATICA E OBJETIVOS: As técnicas clássicas para punção venosa central são realizadas com base em referências anatômicas de superfície e conhecimento da anatomia vascular da região em que se realizará a punção. O uso do ultra-som permite a realização da punção sob visão direta das estruturas vasculares, peri-vasculares e da agulha de punção. O objetivo deste relato foi descrever o uso do ultra-som no auxílio de acesso venoso central em paciente obeso e com adenomegalias. RELATO DO CASO: Paciente do sexo masculino, branco, 28 anos, 1,70 m, 120 kg, com diagnóstico de linfoma de Hodgkin esclerose nodular. Solicitado ao Serviço de Anestesiologia do Hospital Governador Celso Ramos, punção de veia jugular interna direita guiada por ultra-som devido à presença de gânglio supraclavicular que prejudicava a referência anatômica de punção e à obesidade do paciente. Após a obtenção da melhor imagem a veia jugular interna esquerda foi puncionada e colocado um cateter venoso de triplo lúmen. A punção foi única, com progressão fácil do cateter e realizada sem complicações. CONCLUSÕES: O uso da ultra-sonografia para punção venosa central pode evitar complicações tornando o procedimento mais seguro para o paciente.

  15. Tratamento de linfocele inguinal pós-operatória com injeção de cola de fibrina: relato de caso Treatment of postoperative inguinal lymphocele with fibrin glue injection: case report

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    Priscila Nunes Boaventura

    2007-06-01

    Full Text Available O paciente desenvolveu linforragia na região inguinal direita, depois de ponte aorto-bifemoral com enxerto de dácron®. Não respondeu ao tratamento conservador com cuidados locais e compressão. Foi realizado exame de ultra-sonografia Doppler, que evidenciou grande linfocele (6,4 x 3,36 x 6,1 cm, tratada pelo esvaziamento da loja por aspiração e injeção de cola de fibrina (1,6 mL em seu interior. O paciente se recuperou sem intercorrências e sem recidiva, após 3 meses de seguimento.The patient developed lymphatic drainage in the right groin after an aortobifemoral bypass with Dacron® graft. Conservative treatment with local wound care and compression was unsuccessful. Duplex scan showed a 6.4 x 3.36 x 6.1 cm lymphocele, which was treated by aspiration and injection of fibrin glue (1.6 mL. The patient recovered uneventfully and without recurrence after a 3-month follow-up.

  16. Ultra-sonografia da aorta abdominal e de seus ramos em cães Ultrasonography of abdominal aorta and its branches in dogs

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    Lilian Kamikawa

    2007-04-01

    Full Text Available O ultra-som bidimensional e o ultra-som Doppler foram utilizados para avaliar a biometria e a hemodinâmica da aorta abdominal e artérias ilíacas externas de 131cães clinicamente normais. Os resultados da avaliação biométrica da aorta abdominal indicaram um diâmetro médio de 0,80cm para o seu segmento diafragmático (AOD; 0,74cm para o seu segmento caudal às artérias renais (AOR e 0,69cm para o segmento cranial à sua bifurcação (AOT. A artéria ilíaca externa direita (AIED apresentou o diâmetro médio de 0,42cm e a artéria ilíaca externa esquerda (AIEE o diâmetro médio de 0,39. O estudo hemodinâmico da aorta abdominal apresentou velocidade de pico sistólico médio de 104,00cm/s para AOR; 99,61cm/s para AOT; 85,47cm/s para AIED e 99,51cm/s para AIEE. Verificaram-se correlações de diferentes intensidades entre os diâmetros vasculares em diferentes pontos de tomadas e os fatores biométricos corpóreos (CRL. Correlações baixas foram observadas quando esses diâmetros foram confrontados com a idade.A duplex ultrasound system incorporating a pulsed wave Doppler ultrasound probe with conventional B-mode real-time imaging was used to evaluate the biometric and the hemodynamic of abdominal aorta and external iliac arteries of a hundred and thirty one normal dogs. Results of biometrics of abdominal aorta, presented a mean diameter of 0.80cm in its diaphragmatic segment (AOD; 0.74cm in its segment caudal to the renal arteries (AOR and 0.69cm in the segment cranial to its termination (AOT. The right-external-iliac artery (AIED presented a mean diameter of 0.42cm and the left-external iliac artery (AIEE a mean diameter of 0.39cm. The hemodynamic study of the abdominal aorta presented a medium systolic peak velocity to AOR of 104cm per sec.; to AOT of 99.61cm per sec.; to AIED of 85.47cm per sec. and to AIEE of 99.51cm per sec. Correlations of different intensities between the vascular diameters have been verified between the

  17. Efeitos da Histerectomia Total Abdominal sobre o Fluxo Sangüíneo Ovariano Effect of Total Abdominal Hysterectomy on Ovarian Blood Supply

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    Eliana Aguiar Petri Nahás

    2002-06-01

    Full Text Available Objetivo: avaliar os efeitos da histerectomia total abdominal (HTA sobre o fluxo sangüíneo ovariano, em mulheres no menacme, por meio da dopplervelocimetria e ultra-sonografia transvaginal. Métodos: estudo prospectivo no qual foram incluídas 61 mulheres, com idade igual ou inferior a 40 anos. As pacientes foram divididas em dois grupos: G1, com 31 pacientes submetidas à HTA, e G2, com 30 mulheres normais não submetidas à cirurgia. Somente foram incluídas pacientes eumenorréicas, ovulatórias, não-obesas ou fumantes, sem cirurgias ou doenças ovarianas prévias. Avaliou-se o fluxo sangüíneo das artérias ovarianas, inicialmente e aos 6 e 12 meses, pelo índice de pulsatilidade (IP na dopplervelocimetria, e o volume ovariano pela ultra-sonografia transvaginal (US. Para análise estatística empregou-se teste t pareado, análise de perfil, teste de Friedman e teste de Mann-Whitney. Resultados: na comparação estatística inicial os grupos foram homogêneos quanto às características epidemiológicas e quanto aos demais parâmetros avaliados neste estudo. Nas pacientes submetidas à histerectomia, observaram-se aos 6 e 12 meses aumento do volume ovariano ao US e diminuição do IP avaliado pela dopplervelocimetria (pPurpose: to evaluate the effect of total abdominal hysterectomy on ovarian blood supply in women in reproductive age, using transvaginal color Doppler. Methods: a prospective study was carried out on 61 40-year-old or younger women. They were divided into two groups: G1, 31 patients submitted to hysterectomy, and G2, 30 normal women. Criteria of inclusion: normal ovarian function at baseline, normal body weight, without expasure to tobacco, no history of laparotomy or ovarian pathology. The pulsatility index (PI of ovarian arteries determined by Doppler and the transvaginal ultrasonographic measurement of the ovarian volume were performed at three moments: baseline, 6 and 12 months. Results: at baseline the groups were

  18. Mismatch paciente-prótesis aórtica. Comparación alejada por eco-Doppler transtorácico versus el estimado en el preoperatorio

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    Gabriel Converso

    2008-01-01

    Full Text Available Introducción:El mismatch paciente-prótesis (MPP aórtica se asocia con peor evolución posoperatoria.La utilización del área del orificio aórtico efectivo (AOE para cada tipo de prótesis, indexado por la superficie corporal (SC en el momento quirúrgico, puede permitir la elección de un tamaño de prótesis adecuado para cada paciente y así evitar el MPP.ObjetivoComparar la estimación de MPP por las AOE tabuladas con la diagnosticada en el posoperatorio alejado por eco-Doppler.Material y métodosSe analizaron retrospectivamente 57 pacientes, 43 hombres, con prótesis aórtica, operados más de 6 meses antes del estudio. Se calculó la SC del parte quirúrgico y el AOE indexada tabulada, el AOE posquirúrgica con eco-Doppler transtorácico por la ecuación de continuidad y se comparó el MPP prequirúrgico y posquirúrgico. Se consideró MPP aórtico un AOE indexada < 0,75 cm2/m2.ResultadosSe observó una prevalencia de MPP preoperatorio del 29,8% y posoperatorio del 54,4% (p = 0,029, con el 31% de MMP grave. La prevalencia de sobrepeso en la muestra estudiada fue del 80%.ConclusionesEn este grupo de pacientes con alta prevalencia de sobrepeso, la estimación del AOE preoperatoria indexada por SC de cada tipo de prótesis para predecir el MPP posoperatorio mostró diferencias significativas entre el diagnóstico del MPP estimado en el preoperatorio y el calculado por eco-Doppler en el posoperatorio. En futuros estudios es necesaria la inclusión de un grupo poblacional mayor, así como la revisión del método de cálculo del área valvular (p. ej., del tracto de salida del ventrículo izquierdo.

  19. Amadurecimento precoce da placenta avaliada pela ultra-sonografia e prognóstico perinatal Early placental maturation evaluated by ultrasound and perinatal prognosis

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    Ana Patrícia Santos de Queiroz

    2006-03-01

    Full Text Available OBJETIVO: descrever os resultados maternos e perinatais das gestações com amadurecimento precoce da placenta detectado pela ultra-sonografia. MÉTODOS: realizou-se estudo retrospectivo, descritivo, tipo série de casos, com comparação de grupos. Foram incluídas 146 gestantes, internadas entre janeiro de 2000 e dezembro de 2002 e em cujo prontuário constavam diagnóstico de amadurecimento precoce da placenta (presença de placenta grau II antes da 32ª semana de gestação ou grau III, antes da 35ª semana de gestação e descrição das condições materno-fetais. Foram excluídas gestantes com diagnóstico de: amniorrexe prematura, gravidez múltipla, forma aguda de descolamento prematuro de placenta normoinserida e malformação fetal. As complicações clínico-obstétricas foram: doenças hipertensivas, redução do crescimento intra-uterino, alterações do volume de líquido amniótico, infecções, diabete materno, anemia falciforme, soropositividade para HIV, drogadição, litíase renal, epilepsia e asma brônquica. Pelos prontuários, foram identificadas 106 gestantes com complicações clínico-obstétricas (Gcom e 40, sem essas complicações (Gsem. Para comparação entre os grupos, empregaram-se os testes de chi2 e exato de Fisher, ao nível de significância de 0,05. RESULTADOS: o grupo Gcom apresentou maior freqüência de oligoâmnio (27,3%, restrição de crescimento intra-uterino (44,3% e cesárea antecedente ao trabalho de parto (36,8%. Comparado ao grupo Gsem, o Gcom caracterizou-se por maior incidência de óbitos fetais, prematuros (58,8 versus 40%, menor índice de Apgar de 5º minuto, peso ao nascer PURPOSE: to describe perinatal and obstetric characteristics of pregnant women with ultrasonographic early placental aging. METHODS: using a retrospective, descriptive, series of cases, with group comparison, the authors analyzed the data of 146 pregnant women, whose diagnosis of placental early aging (presence of grade

  20. Valor da mamotomia no diagnóstico e na terapia de lesões não palpáveis Usefulness of mammoty in diagnosis and therapy of nonpalpable lesions

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    Aline Cristina Camacho Ambrosio

    2004-02-01

    Full Text Available OBJETIVOS: avaliar a acurácia diagnóstica da biópsia direcional assistida à vácuo (mamotomia, guiada por ultra-sonografia, no diagnóstico das lesões mamárias não palpáveis, comparando-a com a biópsia excisional, e estimar o valor terapêutico da mamotomia em lesões benignas não palpáveis. MÉTODOS: foram incluídas 114 pacientes, as quais apresentavam lesões mamárias não palpáveis, visíveis à ultra-sonografia. As pacientes foram encaminhadas devido mastalgia ou alteração mamográfica detectada previamente, com solicitação de avaliação ultra-sonográfica complementar. Todas foram submetidas à mamotomia guiada por ultra-sonografia com Mammotome® (Biopsys, Irvine, Califórnia, com sonda gauge 11. A biópsia excisional foi realizada com agulhamento prévio daquelas pacientes que apresentaram lesão residual após a mamotomia, ou seja, em 88 pacientes. Para comparar os resultados do material obtido por mamotomia com os da biópsia excisional foram calculados os índices de sensibilidade e especificidade, valores preditivos positivo e negativo, e a proporção de concordância. As sensibilidades, assim como as especificidades e as proporções de concordância dos dois exames, foram comparadas por meio da estatística de Wald, utilizando um modelo para dados categorizados. RESULTADOS: das 114 pacientes, 88 submeteram-se a biópsia excisional. As 26 restantes não apresentaram lesões pós-mamotomia, visíveis à ultra-sonografia, sendo seguidas por um ano sem alterações nos exames semestrais, tanto mamográficos quanto ultra-sonográficos. Tratava-se de lesões menores do que 1,5 cm de diâmetro. Dentre as 88 pacientes submetidas à biópsia excisional 69 apresentaram lesões benignas (78,4% e, 19 (21,6%, malignas. A mamotomia diagnosticou 16 das lesões malignas, com três resultados falso-negativos e nenhum falso-positivo. Os resultados falsos ocorreram: nos primeiros casos realizados, mostrando a existência de curva

  1. Ovários policísticos em meninas e adolescentes normais: uma avaliação ultra-sonográfica

    OpenAIRE

    Teixeira Rosimere J.; Silva Valéria C.G.; Freitas Josele R.; Henriques Jodélia L.M.; Guimarães Marília M.

    2001-01-01

    Realizamos ultra-sonografia pélvica em tempo real e de alta resolução em 140 meninas com idade entre dois e 18 anos, para descrever a prevalência de ovários policísticos durante o desenvolvimento puberal normal. O volume dos ovários foi calculado e sua estrutura classificada como homogênea, microcística, multicística, policística e folicular. O volume aumentou e a freqüência das classes ovarianas variou de acordo com o status puberal. Os ovários eram de aspecto policístico em 8% (duas meninas...

  2. Classificação ultra-sonográfica do derrame pleural e do empiema parapneumônico Ultrasound classification of pleural effusion and parapneumonic empyema

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    Luís Marcelo Inaco Cirino

    2002-03-01

    Full Text Available Os autores correlacionam as alterações anatomopatológicas da cavidade pleural com os achados ultra-sonográficos no derrame pleural e no empiema parapneumônico e apresentam uma classificação baseada nestes dados. Concluem que a ultra-sonografia é método diagnóstico fidedigno para inferir a fase anatomopatológica da doença pleural, bem como auxiliar na escolha da alternativa de tratamento.We correlated the anatomopathological abnormalities of the pleural space with the ultrasound findings in patients with pleural effusion and/or parapneumonic empyema and proposed a classification based on these results. Ultrasonography is a reliable method to infer the anatomopathological phase of pleural disease and consequently may be of help in the choice of the most suitable treatment.

  3. O uso da ressonância magnética na investigação do câncer mamário Magnetic resonance imaging in the evaluation of breast cancer

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    Beatriz Regina Alvares

    2003-12-01

    Full Text Available Os métodos diagnósticos de imagem mamografia, ultra-sonografia e cintilografia são exames imprescindíveis no diagnóstico do câncer de mama e no acompanhamento após o procedimento cirúrgico, porém, todos apresentam limitações específicas. Atualmente, a ressonância magnética tem-se revelado um método diagnóstico promissor para avaliar mais detalhadamente lesões tumorais do parênquima mamário. Neste trabalho os autores descrevem as principais indicações e os achados da ressonância magnética no câncer de mama, bem como comparam o seu desempenho com o dos outros métodos de imagem - mamografia, ultra-sonografia e cintilografia -, incluindo as vantagens e limitações de cada modalidade.Mammography, ultrasonography and scintimammography are essential examinations for the diagnosis and post-surgical follow-up of patients with breast cancer, although all these modalities may present specific limitations. In recent years magnetic resonance imaging has demonstrated good performance in detecting breast tumors in the mammary gland. In this study the authors describe the magnetic resonance imaging main indications and findings in patients with breast cancer, and compare the performance of mammography, ultrasonography and scintimammography, including the advantages and limitations of each modality.

  4. Biomecânica ultra-sonográfica da deglutição: estudo preliminar Sonographic evaluation of swallowing biomechanics: a preliminary study

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    Cinthya da Silva Lynch

    2008-08-01

    Full Text Available OBJETIVO: Verificar, por meio da ultra-sonografia, os parâmetros espaciais do complexo hiolaríngeo na dinâmica da deglutição e a associação entre idade e efeitos. MATERIAIS E MÉTODOS: Neste estudo quantitativo e prospectivo foram incluídos 39 indivíduos sadios, de ambos os gêneros, na faixa etária de 20 a 70 anos (média, 45,56; desvio-padrão, 14,53. Avaliou-se a biomecânica da deglutição correspondente à medida da distância entre a porção superior do osso hióide e a borda superior da cartilagem tireóide, no momento de máxima elevação laríngea. As medidas foram realizadas com a ingestão de alimentos de consistências líquida e pastosa. RESULTADOS: A variação da distância da laringe ao hióide apresentou associação positiva com a idade, somente na deglutição de alimento pastoso, consistência na qual é solicitada maior atividade de propulsão lingual do que nos líquidos. CONCLUSÃO: É possível que o aumento da distância entre o hióide e a laringe, que representa menor elevação laríngea, na deglutição de pastosos, ocorra por efeito do envelhecimento, processo no qual se verifica diminuição de reservas funcionais, mesmo em indivíduos sadios. A ultra-sonografia pode detectar comportamentos relacionados a consistências alimentares, o que mostra sua possível potencialidade diagnóstica na avaliação da deglutição.OBJECTIVE: To evaluate, by means of ultrasonography, the spatial parameters of the hyolaryngeal complex in the deglutition dynamics as well the correlation between age and effects. MATERIALS AND METHODS: The present prospective and quantitative study included 39 healthy men and women in the age range between 20 and 70 years (mean, 45.56; standard deviation, 14.53. The swallowing biomechanics corresponding to the measurement of the distance between the upper portion of the hyoid bone and the upper rim of the thyroid cartilage at the moment of maximum laryngeal elevation was evaluated

  5. Avaliação do bem-estar fetal pela dopplervelocimetria com mapeamento em cores Evaluation of fetal well-being through color doppler velocimetry

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    Cleide Mara Mazzotti de Oliveira Franzin

    1999-01-01

    Full Text Available Objetivos: Avaliar a eficiência do exame dopplervelocimétrico no diagnóstico do bem-estar fetal. Metodologia: Foram analisadas 130 gestantes atendidas no Serviço de Ultra-Sonografia do Centro de Atenção Integral à Saúde da Mulher da Universidade Estadual de Campinas, entre a 28ª e a 42ª semana. Foram feitas correlações entre o Doppler das artérias umbilical, cerebral média e aorta abdominal fetal com os resultados perinatais adversos. As gestantes selecionadas para o estudo foram submetidas eletivamente ao parto cesáreo, no máximo quatro horas após o exame Doppler. Considerou-se como resultados perinatais adversos: índice de Apgar ao 5º minuto menor que sete, internação em unidade de terapia intensiva neonatal, retardo de crescimento intra-uterino, sofrimento fetal agudo, mortalidade perinatal, hipoglicemia, enterocolite necrosante e hemorragia cerebral. Os índices de impedância das artérias umbilical, cerebral média e aorta abdominal foram relacionados caso a caso com os resultados perinatais adversos. Resultados: a relação sístole/diástole da artéria umbilical apresentou maior sensibilidade (80,76% do que o índice de pulsatilidade e índice de resistência da artéria umbilical. O estudo Doppler da artéria umbilical apresentou melhor sensibilidade que o da artéria cerebral média e da aorta abdominal na detecção de resultados perinatais adversos. Conclusão: a dopplervelocimetria das artérias umbilical e cerebral média apresentou boa capacidade de avaliação do bem-estar fetal e associação significativa com resultados perinatais adversos.Purpose: to evaluate the accuracy of Doppler velocimetry in the diagnosis of fetal well-being. Methods: a total of 130 pregnant women assisted at the Ultrasound Unit of the Center for Integral Assistance of Women's Health, UNICAMP, between the 28th and 42nd gestational weeks was analyzed. The correlation between fetal umbilical and middle cerebral arteries, abdominal

  6. Correlações simples entre as medidas de ultra-som e a composição da carcaça de bovinos jovens Correlations between ultrasound measurements and carcass composition of young bulls

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    Liliane Suguisawa

    2006-02-01

    Full Text Available Neste estudo avaliaram-se as correlações entre as medidas ultra-sonográficas e as características de carcaça de 115 bovinos jovens (Nelore, ½ Angus Nelore, ½ Simental Nelore e Canchim, com peso inicial médio de 329 kg e dois tamanhos à maturidade (pequeno e grande, em um sistema de produção do novilho superprecoce. Aos 120 dias de confinamento, foram realizadas a pesagem e medida da área de olho-de-lombo (AOL e da gordura subcutânea (ECG, via ultra-sonografia. Após o abate, foram coletadas as medidas de AOL e ECG na carcaça e os pesos de traseiro, dianteiro e cortes cárneos comerciais, determinando-se também a composição corporal dos animais. Foram calculados os rendimentos de carcaça, cortes cárneos, traseiro, da AOL ultra-som por 100 kg de PV e da AOL carcaça por 100 kg de peso de carcaça. Dados da composição da carcaça indicaram alta deposição muscular nos animais ½ Simental Nelore e Canchim e expressiva deposição de tecido adiposo nos animais Nelore. No entanto, os animais ½ Angus Nelore mostraram-se mais apropriados para confinamento no sistema de produção do superprecoce, pois equilibraram musculosidade e gordura de acabamento. Os resultados demonstraram que a AOL tem relação com a musculosidade da carcaça e que, à medida que há seleção para o incremento desta característica, ocorre diminuição da ECG, como resultado da correlação negativa da ECG com a porcentagem de traseiro e AOL. Não foi observada diferença na composição entre os dois grupos de tamanho à maturidade, provavelmente em razão da pequena variação entre eles. Como as correlações envolvendo a AOL e a ECG por ultra-som e as mesmas medidas na carcaça apresentam resultados similares, validou-se a utilização da técnica da ultra-sonografia como alternativa para predição das características da carcaça de bovinos.The objective of this study was to evaluate correlations between ultrasonography measurements and carcass

  7. Ecocardiografia por Doppler tecidual no diagnóstico de rejeição após transplante cardíaco

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    Marcos Valério Coimbra Resende

    2011-07-01

    Full Text Available FUNDAMENTO: A biópsia endomiocárdica (BEM é o método padrão-ouro para o diagnóstico de rejeição celular (RC após transplante cardíaco (TC. OBJETIVO: Testar a hipótese de que o exame de imagem por Doppler tecidual (IDT pode detectar RC > 3A e agregar informação diagnóstica, comparado ao Doppler convencional. MÉTODOS: Cinquenta e quatro pacientes com TC foram submetidos à BEM e estudo ecocardiográfico através de IDT em até 24 horas. Comparamos os pacientes com TC e RC > 3A com pacientes com TC e RC 3A em 39/129 (30,2% das BEM. O melhor preditor isolado para o diagnóstico de RC foi a a'LAT, com sensibilidade de 76,3%, especificidade de 73,8% (p = 0,001. Na análise multivariada, a a'LAT (p = 0,001, a'SEP (p = 0,002, relação e'/a' LAT (p = 0,006, relação e'Mitral/ e'LAT (p = 0,014, SINF (p = 0,009 foram preditores de RC > 3A. Obtivemos um escore com sensibilidade de 88,2%, acurácia de 79,6%, e valor preditivo negativo de 92,9% para diagnosticar RC > 3A. O Doppler convencional (fluxo mitral e pulmonar venoso não foi relevante para predizer a RC > 3A. CONCLUSÃO: O estudo de IDT agregou informação diagnóstica para predizer RC > 3A quando comparado ao Doppler convencional. O modelo baseado em IDT pode ser tornar um método em potencial para detectar RC > 3A após TC.

  8. Persistência hiperplástica do vítreo primitivo: avaliação por métodos de imagem

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    Jacob Beatriz Mahmud

    2003-01-01

    Full Text Available Persistência hiperplásica do vítreo primitivo (PHVP é um desenvolvimento anormal, afetando crianças, resultante da falha de regressão do vítreo primitivo e dos vasos hialóides, com proliferação de tecido conectivo. A PHVP pode ter três variações: uma anterior, outra posterior e uma terceira com a combinação das duas. Clinicamente manifesta-se como leucocoria (reflexo branco pupilar em um olho de dimensões reduzidas. Esta anomalia é usualmente unilateral e não associada com outros achados sistêmicos. Leucocoria, descolamento de retina, pregas retinianas e catarata podem confundir PHVP com outras afecções oculares que têm achados semelhantes. Retinoblastoma, catarata congênita, retinopatia da prematuridade e pseudogliomas são doenças com achados semelhantes aos da PHVP. A visualização direta dos remanescentes do sistema vascular hialóide fetal é a melhor evidência da lesão presente, se não fosse, muitas vezes impossivel, à fundoscopia, devido à opacidade do tecido. Nestes casos, a visualização indireta, por meio de ultra-sonografia, tomografia computadorizada e ressonância magnética, fornece o diagnóstico. As imagens obtidas por estes métodos proporcionam, ainda, informações e diagnóstico diferencial com outras doenças, particularmente com o retinoblastoma. Os autores fazem uma revisão na literatura e apresentam um estudo iconográfico das imagens e achados da PHVP.

  9. Estimativa do Peso Fetal: Comparação Entre um Método Clínico e a Ultra-Sonografia Estimation of Fetal Weight: Comparison Between a Clinical Method and Ultrasonography

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    Alexandre Faisal Cury

    1998-12-01

    Full Text Available Objetivo: avaliar a validade da estimativa do peso fetal por método baseado na altura uterina - regra de Johnson. Métodos: foram estudadas 101 gestantes e seus recém-nascidos (RN, estimando-se o peso fetal pela utilização da regra de Johnson adaptada, que consiste em aplicação clínica de modelo matemático para cálculo do peso fetal baseado na altura uterina e na altura da apresentação fetal. O peso estimado foi obtido no dia do parto e foi comparado com o peso observado ao nascer, que constituiu o controle da análise da validade do método empregado. Na mesma data foi realizada ultra-sonografia obstétrica (US detalhada, que inclui cálculo do peso fetal pela aplicação das tabelas de Sheppard, e este peso, estimado pela US, foi comparado ao peso observado ao nascer. Resultados: os resultados destas comparações mostraram que a estimativa clínica empregada nesta casuística tem valor semelhante à US para avaliação do peso ao nascer: a margem de acerto do método clínico com variações de 5%, 10% e 15% entre peso estimado e peso observado foi de 55,3%, 73% e 86,7% respectivamente, e, para o US, de 60,7%, 75,4% e 91,1%, respectivamente. Conclusões:quando comparados, estes valores não se mostraram diferentes do ponto de vista estatístico, permitindo concluir-se que a avaliação clínica mostra acurácia semelhante à da US para o cálculo do peso ao nascer.Purpose: to assess the validity of fetal weight estimation by a method based on uterine height -- Johnson's rule. Methods: one hundred and one pregnant women and their newborn children were studied. The fetal weight was estimated using an adaptation of Johnson's rule, which consists of the clinical application of a mathematical model to calculate the fetal weight based on the uterine height and the height of fetal presentation. The estimated weight was obtained on the day of delivery and was compared to the weight observed after birth. This, in turn, was the control of

  10. A micro-Doppler sonar for acoustic surveillance in sensor networks

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    Zhang, Zhaonian

    Wireless sensor networks have been employed in a wide variety of applications, despite the limited energy and communication resources at each sensor node. Low power custom VLSI chips implementing passive acoustic sensing algorithms have been successfully integrated into an acoustic surveillance unit and demonstrated for detection and location of sound sources. In this dissertation, I explore active and passive acoustic sensing techniques, signal processing and classification algorithms for detection and classification in a multinodal sensor network environment. I will present the design and characterization of a continuous-wave micro-Doppler sonar to image objects with articulated moving components. As an example application for this system, we use it to image gaits of humans and four-legged animals. I will present the micro-Doppler gait signatures of a walking person, a dog and a horse. I will discuss the resolution and range of this micro-Doppler sonar and use experimental results to support the theoretical analyses. In order to reduce the data rate and make the system amenable to wireless sensor networks, I will present a second micro-Doppler sonar that uses bandpass sampling for data acquisition. Speech recognition algorithms are explored for biometric identifications from one's gait, and I will present and compare the classification performance of the two systems. The acoustic micro-Doppler sonar design and biometric identification results are the first in the field as the previous work used either video camera or microwave technology. I will also review bearing estimation algorithms and present results of applying these algorithms for bearing estimation and tracking of moving vehicles. Another major source of the power consumption at each sensor node is the wireless interface. To address the need of low power communications in a wireless sensor network, I will also discuss the design and implementation of ultra wideband transmitters in a three dimensional

  11. Correlação entre o exame clínico, a mamografia e a ultra-sonografia com o exame anatomopatológico na determinação do tamanho tumoral no câncer de mama Correlation between clinical examination, mammography and ultrasonography with histopathological exam in the determination of tumor size in breast cancer

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    Fernanda Monteiro de Paula Siqueira

    2008-03-01

    Full Text Available OBJETIVO: avaliar qual o melhor método entre o exame clínico (EC, a mamografia (MMG e a ultra-sonografia (US na determinação pré-operatória do tamanho tumoral no câncer de mama, tendo como referência o exame anatomopatológico. MÉTODOS: foram incluídas neste estudo 184 pacientes com lesões mamárias detectadas por MMG e US, palpáveis ou não, e que foram submetidas a ressecção cirúrgica do tumor, com diagnóstico histopatológico de câncer de mama. O maior diâmetro tumoral foi avaliado por EC, MMG e US por um mesmo examinador, e a medida obtida por cada método foi correlacionada com o diâmetro máximo obtido pelo exame anatomopatológico. A análise comparativa foi feita por meio do coeficiente de correlação de Pearson (r. RESULTADOS: o coeficiente de correlação de Pearson encontrado entre o exame anatomopatológico e o EC foi 0,8; entre o exame anatomopatológico e a MMG foi 0,7 e entre o exame anatomopatológico e a US foi 0,7 (pPURPOSE: to evaluate which method is the best to determine pre-surgically the size of breast cancer: clinical examination, mammography or ultrasonography, using as a reference the anatomopathological exam. METHODS: this study has included 184 patients with palpable-or-not breast lesions, detected by mammography and ultrasonography, that were submitted to surgical resection of the tumor, with histopathological diagnosis of breast cancer. The same examiner evaluated clinically the largest tumoral diameter, through clinical examination, mammography and ultrasonography, and the measurements obtained by each method were correlated with the maximum diameter obtained by the anatomopathological exam. The comparative analysis has been done by Pearson's correlation coefficient (r. RESULTS: Pearson's correlation coefficient between the anatomopathological and the clinical exams was 0.8; between the anatomopathological exam and the mammography, 0.7; and between anatomopathological exam and ultrasonography 0

  12. Índice orientador do tratamento sistêmico da gravidez ectópica íntegra com dose única de metotrexato Index for the systemic treatment of unruptured ectopic pregnancy with a single dose of methotrexate

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    Julio Elito Junior

    1998-04-01

    Full Text Available Foi realizado estudo longitudinal em 42 pacientes com diagnóstico de gravidez ectópica íntegra, com o intuito de se elaborar um índice orientador do uso sistêmico de metotrexato em dose única (50 mg/m² por via intramuscular. O acompanhamento se fez através de dosagens de beta-hCG (fração beta do hormônio gonadotrópico coriônico realizadas no 1º, 4º e 7º dias após o emprego do quimioterápico. Quando ocorreu queda de 15% ou mais nos títulos de beta-hCG, apurados no 4º e no 7º dia, as pacientes receberam alta hospitalar e seguimento ambulatorial com dosagens semanais de beta-hCG até que se atingissem níveis inferiores a 5 mUI/ml. Foi elaborado um índice orientador do tratamento sistêmico com metotrexato baseado nos seguintes parâmetros: (1 valores iniciais de beta-hCG; (2 aspecto da imagem à ultra-sonografia (hematossalpinge, anel tubário, embrião vivo; (3 maior diâmetro da massa anexial; (4 quantidade de líquido livre; (5 fluxo vascular medido por meio do doppler colorido. Cada parâmetro recebeu pontuação de 0 a 2. A nota zero significa elemento de mau prognóstico, a nota dois indica parâmetros favoráveis e a nota um, situações intermediárias. O índice de sucesso com dose única foi de 69,0% (29/42 pacientes. A ultra-sonografia transvaginal com doppler colorido foi realizada em 20 das 42 pacientes do estudo. Neste grupo de 20 pacientes o sucesso do tratamento ocorreu em 75,0% dos casos (15/20. Entre as 22 pacientes que não foram avaliadas com doppler colorido a média das notas do índice nos casos de sucesso foi de 6,6, nas de insucesso 3,1. No grupo de pacientes avaliadas por doppler (20 pacientes as médias foram de 7,9 (sucesso e 4,2 (fracasso. No presente estudo a nota de corte foi estabelecida levando-se em conta o valor abaixo do qual o tratamento não foi efetivo e correspondeu a cinco, pois 93,75% das pacientes com nota superior a 5 evoluíram com sucesso (15/16, ao passo que notas inferiores ou

  13. Doppler-guided hemorrhoidal artery ligation in the management of symptomatic hemorrhoids Ligadura de las arterias hemorroidales guiada por Doppler en el tratamiento de las hemorroides sintomáticas

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    J. M. Ramírez

    2005-02-01

    la intervención. Resultados: el tiempo medio de intervención fue de 27 (rango 18-43 minutos, localizando de media 5 (rango 4-7 ramas arteriales. No existieron complicaciones intraoperatorias. Ningún paciente presentó dolor severo o moderado en alguno de los controles, refiriendo habitualmente molestias anales discretas. La rectorragia autolimitada y el tenesmo fueron las complicaciones post-operatorias más frecuentes. Tras el seguimiento a 1 año, 19 enfermos estaban asintomáticos y en 6 ocasiones los síntomas habían disminuido significativamente, en el resto la intervención fue ineficaz. Agrupados los pacientes por grados, la técnica presentó malos resultados en sólo 3 pacientes con hemorroides grado III, pero en hemorroides grado IV, los resultados fueron malos en 4 de los 5 pacientes. Conclusiones: la ligadura de la arteria hemorroidal guiada por Doppler es una técnica sencilla, bien tolerada, con buenos resultados en hemorroides grado III.

  14. Acidente vascular cerebral e outras complicações do sistema nervoso central nas doenças falciformes Stroke and other vascular complications of the central nervous system in sickle cell disease

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    Ivan L. Angulo

    2007-09-01

    Full Text Available A principal complicação da doença falciforme na infância é a das artérias cerebrais, mas após os 20 anos também pode se manifestar, como seqüela de lesões anteriores ou neoformadas. A vasculopatia tem a maior importância no desenvolvimento da criança e na qualidade de vida. Além do acidente vascular cerebral completo ou incompleto ("silencioso", existem outras complicações do sistema nervoso central, porém não exclusivas. O diagnóstico da vasculopatia cerebral falciforme necessita auxílio neurorradiológico. O tratamento se faz basicamente com transfusões de eritrócitos contendo hemoglobina A. O objetivo deste trabalho é rever a literatura médica, procurando selecionar a melhor conduta em diagnóstico e tratamento que seja possível empregar de imediato, para reduzir a morbidade e mortalidade da vasculopatia cerebral e elevar a qualidade de vida dos pacientes, principalmente na infância. Os fatores de risco clínicos e laboratoriais, incluindo a triagem por ultra-sonografia Doppler das artérias cerebrais e imagens de ressonância magnética, devem influenciar a decisão de instituir transfusões crônicas e a quelação do ferro transfusional deve acompanhar este tratamento.In children with sickle cell disease, cerebral arteries are prone to lesions that may cause deficiencies and poor quality of life. After the age of 20, new lesions may also occur. Besides stroke and silent cerebral ischemia, other lesions may occur. Radiologic images are necessary to diagnose and blood transfusions to treat. We reviewed the literature to choose best practices and guidelines to reduce morbidity and mortality and improve the quality of life of children with sickle cell disease. Risk factors identified from clinical and laboratory data and screening by Doppler ultrasonography and magnetic resonance must be used in order to make decisions about transfusion and iron chelation therapy.

  15. Controle ultra-sonográfico de gestações, de mortalidades embrionárias e fetais e do sexo de fetos bovinos zebuínos

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    Breno José Pelozo de Barros

    2001-01-01

    Full Text Available Este trabalho avaliou a eficácia do ultra-som no diagnóstico precoce de prenhez e nas avaliações das mortalidades embrionárias e fetais e dos sexos de fetos em dois grupos de vacas zebuínas. Os animais que não retornaram ao estro aos 21 dias da Inseminação Artificial (G1 ou aos 14 dias da Transferência de Embriões (G2B foram examinados aos 25 dias de gestação para o diagnóstico precoce de prenhez, aos 45 dias para avaliação das perdas embrionárias entre 26 e 45 dias e aos 60 dias para avaliações das perdas fetais entre 45 e 60 dias e dos sexos de fetos. O Grupo G2A foi examinado por palpação retal aos 45 dias para diagnóstico de prenhez e aos 60 dias para avaliações das perdas fetais e dos sexos de fetos. As taxas de prenhez foram, respectivamente, 94,6%, 88,1% e 83,4% aos 25, 45 e 60 dias de gestação. As taxas de perdas embrionárias e fetais e de abortos foram, respectivamente, 4,6%, 4,7% e 1,2%. As taxas de acertos do diagnóstico precoce de gestação e dos sexos de fetos foram 88,5% e 90,7%, respectivamente. A ultra-sonografia mostrou-se eficaz no diagnóstico precoce de prenhez aos 25 dias, nas avaliações das perdas embrionárias aos 45 dias e fetais aos 60 dias e no diagnóstico do sexo de fetos a partir dos 60 dias de gestação. Os exames ultra-sonográficos não causaram perdas gestacionais nos animais Bos indicus ou Bos indicus X Bos taurus.

  16. Tratamento da síndrome de Budd-Chiari por meio da colocação de tips e de "stent" venoso supra-hepático Transjugular intrahepatic portosystemic shunt (TIPS and suprahepatic venous stenting in the management of Budd-Chiari syndrome

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    Jurandi A. Bettio

    2002-11-01

    Full Text Available OBJETIVOS: Descrever o uso do "shunt" intra-hepático portossistêmico (TIPS e do "stent" venoso supra-hepático no manejo da síndrome de Budd-Chiari, enfocando suas indicações, aspectos técnicos e benefícios do procedimento. MATERIAIS E MÉTODOS: De janeiro de 1999 a março de 2002, nove casos de síndrome de Budd-Chiari foram encaminhados ao Serviço de Hemodinâmica do Hospital São Lucas, Porto Alegre, RS. A obstrução venosa supra-hepática foi constatada em todos os casos por meio de ultra-sonografia com Doppler em cores. A criação de TIPS foi realizada entre o sistema venoso supra-hepático ou a veia cava inferior e a veia porta, posicionando-se a endoprótese entre as duas abordagens. Doppler em cores pós-procedimento foi efetuado em todos os pacientes em períodos seriados. RESULTADOS: Três casos foram tratados inicialmente com inserção de "stent" venoso por apresentarem estenose preponderante em veias supra-hepáticas. Em dois desses casos ocorreu trombose do "stent", sendo necessária colocação de TIPS. Os demais seis casos foram tratados primariamente com TIPS. Dos oito "shunts" criados, trombose da endoprótese foi constatada em três casos, resolvidas com limpeza dos trombos e dilatação com balão em um caso e inserção de novas próteses nos demais. Embolização com molas de colaterais venosas ectasiadas foi efetuada em um paciente. CONCLUSÕES: A colocação de TIPS constitui-se numa estratégia terapêutica segura e efetiva na síndrome de Budd-Chiari, promovendo uma significativa melhora clínica e hemodinâmica dos pacientes, evitando procedimentos mais invasivos e podendo, em casos sem cirrose estabelecida, servir de tratamento definitivo da hipertensão portal.OBJECTIVE: To evaluate the use of transjugular intrahepatic portosystemic shunt (TIPS and suprahepatic venous stenting in the management of Budd-Chiari syndrome, emphasizing the indications, technical aspects and the advantages of the procedure

  17. Fatores de risco clínicos e ultra-sonográficos relacionados à litíase vesicular assintomática em mulheres

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    Ferreira Adilson Cunha

    2004-01-01

    Full Text Available OBJETIVO: Analisar variáveis clínicas e ultra-sonográficas, como presença ou ausência de barro biliar, espessura da parede e medida transversal da vesícula biliar, idade, paridade, presença ou ausência de diabetes mellitus associadas a litíase vesicular assintomática, bem como determinar a sua prevalência em pacientes submetidas ao exame ultra-sonográfico. MATERAIS E MÉTODOS: Foram analisadas, em estudo prospectivo, 265 pacientes do sexo feminino, atendidas na Escola de Ultra-sonografia e Reciclagem Médica de Ribeirão Preto, durante o período de janeiro a setembro de 2001. RESULTADOS: Evidenciou-se diferença estatisticamente significativa relacionada à litíase da vesícula biliar e espessura da parede da vesícula biliar, barro biliar, diâmetro transverso da vesícula biliar, faixa etária, paridade, passando de 4,1% nas nulíparas para 39,1% nas multíparas e diabéticas. A prevalência de litíase na vesícula biliar em pacientes assintomáticas foi de 14,7%. CONCLUSÃO: A litíase vesicular assintomática em mulheres ocorre principalmente com o decorrer da idade e da paridade. Os achados ultra-sonográficos mais freqüentemente encontrados foram presença de barro biliar e de espessamento da parede da vesícula biliar.

  18. Ultra high frequency induction welding of powder metal compacts

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    Çavdar, Uǧur

    2014-06-01

    Full Text Available The application of the iron based Powder Metal (PM compacts in Ultra High Frequency Induction Welding (UHFIW were reviewed. These PM compacts are used to produce cogs. This study investigates the methods of joining PM materials enforceability with UHFIW in the industry application. Maximum stress and maximum strain of welded PM compacts were determined by three point bending and strength tests. Microhardness and microstructure of induction welded compacts were determined.Soldadura por inducción de ultra alta frecuencia de polvos de metal compactados. Se ha realizado un estudio de la aplicación de polvos de metal (PM de base hierro compactados por soldadura por inducción de ultra alta frecuencia (UHFIW. Estos polvos de metal compactados se utilizan para producir engranajes. Este estudio investiga los métodos de uni.n de los materiales de PM con UHFIW en su aplicación en la industria. La máxima tensión y la máxima deformación de los polvos de metal compactados soldados fueron determinadas por flexión en tres puntos y prueba de resistencia. Se determinó la microdureza y la microestructura de los polvos compactados por soldadura por inducción.

  19. Aneurisma da artéria carótida interna extracraniana: relato de caso Aneurysm of the extracranial internal carotid artery: a case report

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    Marcio Ricardo Taveira Garcia

    2004-08-01

    Full Text Available Os aneurismas verdadeiros da artéria carótida interna extracraniana são raros, ao contrário dos supraclinóideos, somando menos de 4% dos aneurismas periféricos. Eles se apresentam clinicamente como massas palpáveis cervicais, junto à margem inferior do ângulo da mandíbula, causando rouquidão, disfagia e dor por compressão nervosa. Há freqüente associação desta doença com outros aneurismas periféricos devido à sua etiologia principal (aterosclerose. Os aneurismas periféricos são comumente identificados à ultra-sonografia Doppler, quando na vigência de janela acústica adequada. Nesta situação, os aneurismas podem ser avaliados tanto morfológica como hemodinamicamente. Sua identificação e estudo são importantes para prevenir graves complicações, como tromboses, infartos maciços ou embólicos da área correspondente no sistema nervoso central, ruptura e dissecção, além de auxiliar na indicação da melhor conduta terapêutica.Unlike supraclinoid aneurysms, true aneurysms of the extracranial internal carotid artery are extremely rare (less than 4% of the peripheral aneurysms. The commonest presentation is a pulsatile neck swelling below the angle of the jaw associated with hoarseness, dysphagia and pain (neural compression. Concomitance with other peripherical aneurysms is frequent and caused by atherosclerosis. The morphological and hemodynamic features are very well evaluated by Doppler ultrasound, when the acoustic window is satisfactory. Identification and evaluation of these aneurysms are very important to prevent thrombosis, rupture, dissections, massive strokes and embolic brain infarcts, besides helping in the decision of the best treatment.

  20. Volume do embrião estimado pela ultra-sonografia tridimensional entre a sétima e a décima semana de gestação Embryo volume estimated by three-dimensional ultrasonography at seven to ten weeks of pregnancy

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    João Bortoletti Filho

    2008-10-01

    Full Text Available OBJETIVO: avaliar a evolução do volume do embrião (VE entre a sétima e a décima semana de gestação por meio da ultra-sonografia tridimensional. MÉTODOS: realizou-se um estudo de corte transversal com 63 gestantes normais entre a sétima e a décima semana. Os exames ultra-sonográficos foram realizados por meio de um transdutor endocavitário volumétrico. Para o cálculo do VE, utilizou-se o método VOCAL (Virtual Organ Computer-aided Analysis com ângulo de rotação de 12º, com delimitação de 15 planos seqüenciais. Para o VE foram calculadas médias, medianas, desvios padrão e valores máximo e mínimo em todas as idades gestacionais. Para se avaliar a correlação entre o VE e o comprimento cabeça-nádega (CCN foi criado gráfico de dispersão, sendo o ajuste realizado pelo coeficiente de determinação (R². Para se determinarem intervalos de referência do VE em função do CCN, utilizou-se a seguinte fórmula: percentil =VE+K versus dp, com K=1,96. RESULTADOS: o CCN variou de 9,0 a 39,7 mm, com média de 23,9 mm (±7,9 mm, enquanto o VE variou de 0,1 a 7,6 cm³, com média de 2,7 cm³ (±3,2 cm³. O VE foi altamente correlacionado com o CCN, sendo que o melhor ajuste foi obtido com regressão quadrática (VE=0,165 - 0,055 x CCN + 0,005 x CCN²; R²=0,853. O VE médio variou de 0,1 (-0,3 a 0,5 cm³ a 6,7 cm³ (3,8 a 9,7 cm³ no intervalo de 9 a 40 mm do CCN. Neste intervalo o VE aumentou 67 vezes, enquanto o CCN aumentou apenas 4,4 vezes. CONCLUSÕES: o VE é um parâmetro mais sensível que o CCN para avaliar o crescimento embrionário entre a sétima e a décima semana de gestação.PURPOSE: to evaluate the embryo's volume (EV between the seventh and the tenth gestational week, through tridimensional ultrasonography. METHODS: a transversal study with 63 normal pregnant women between the seventh and the tenth gestational week. The ultrasonographical exams have been performed with a volumetric abdominal transducer. Virtual

  1. Reacción posquirúrgica del lecho vascular inducida por el campo magnético de ultra-alta frecuencia

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    Armando Hidalgo de Paz

    1995-06-01

    Full Text Available En 82 ratas blancas adultas se estudió el efecto posoperatorio del campo magnético de ultra- -alta frecuencia (CMUAF sobre el volumen del lecho intramuscular, durante el período de formación de colaterales. El CMUAF se aplicó con el aparato portátil UVCHE-30, con frecuencia de 40,68 MHz y potencias fijas de salida de 15 y 30 W. Luego de seccionar quirúrgicamente las arterias femorales, se aplicó el campo magnético por 2, 6, 10 y 16 semanas. En estos plazos se inyectó mezcla de tinta china-gelatina en el lecho vascular y se obtuvieron cortes micrométricos que se transparentaron y fueron posteriormente leídos por microfotometría. Se observó un marcado aumento del volumen del lecho vascular intramuscular por acción del CMUAF, particularmente en los períodos de 2 y 6 semanas posteriores al inicio del tratamiento. También se evidenció mayor reacción vascular a la acción del CMUAF con potencia de 15 W, en comparación con los resultados en 30 W

  2. Sinais ultra-sonográficos em fetos portadores de toxoplasmose congênita Ultrasonographic markers for fetal congenital toxoplasmosis

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    Júlio César de Faria Couto

    2004-06-01

    Full Text Available OBJETIVO: descrever as alterações ultra-sonográficas em fetos com toxoplasmose congênita, correlacionando-as com o prognóstico neonatal. MÉTODOS: entre junho de 1997 e maio de 2003 foram examinadas 150 gestantes com suspeita de toxoplasmose. A infecção aguda foi confirmada em 72 (48% gestantes e a toxoplasmose congênita foi diagnosticada em 12 (16% fetos. O diagnóstico pré-natal foi realizado pela reação em cadeia da polimerase no líquido amniótico. Todas as pacientes receberam terapia antiparasitária. O acompanhamento ultra-sonográfico foi quinzenal e todos os recém-nascidos foram acompanhados no primeiro ano de vida. RESULTADOS: as alterações ultra-sonográficas foram observadas em oito fetos. Todos apresentavam dilatação ventricular bilateral, associada a calcificações periventriculares em cinco casos. Outras alterações como calcificação hepática, hepatomegalia, poliidrâmnio e derrame pericárdico foram menos freqüentes. Dentre esses fetos, quatro foram neomortos e três apresentaram seqüelas (coriorretinite e retardo neuropsicomotor. Os quatro fetos com ultra-sonografia normal evoluíram satisfatoriamente. CONCLUSÃO: observou-se elevada incidência de alterações ultra-sonográficas nos fetos com toxoplasmose congênita, principalmente cerebrais. Outras alterações como hepatomegalia e derrame pericárdio são menos freqüentes e traduzem infecção sistêmica. O prognóstico dos fetos parece correlacionar-se com a presença de lesões ultra-sonográficas, uma vez que nesse grupo de fetos observou-se alta mortalidade e entre os sobreviventes a incidência de seqüelas foi importante. Os fetos sem alterações ultra-sonográficas evoluíram de forma favorável, sem seqüelas de desenvolvimento. Esses resultados destacam a importância da ultra-sonografia no acompanhamento desses fetos, a fim de se estabelecer um prognóstico e permitir a elaboração de conduta pós-natal adequada.OBJECTIVE: to describe

  3. Estudo Prospectivo das Características Sonográficas no Diagnóstico de Nódulos Sólidos da Mama

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    Paulinelli Régis Resende

    2002-01-01

    Full Text Available Objetivo: avaliar, por meio de estudo prospectivo, o valor de diferentes características ultra-sonográficas dos nódulos sólidos, na diferenciação de lesões malignas e benignas da mama. Métodos: foram incluídas 142 pacientes do Programa de Mastologia do Departamento de Ginecologia e Obstetrícia da Universidade Federal de Goiás com nódulos sólidos da mama. A ultra-sonografia mamária foi realizada pelo médico estagiário de mastologia, acompanhado do preceptor. As seis características estudadas foram: contornos, ecos internos, ecos posteriores, diferença dos diâmetros, ligamentos de Cooper e halo ecogênico. Cada descrição característica ultra-sonográfica foi analisada estatisticamente e comparada, após a exérese da lesão, com o resultado do exame anatomopatológico. Resultados: dentre as 142 pacientes incluídas no estudo, 90 (63% tiveram suas lesões ressecadas, com diagnóstico de 77 tumores benignos (86% e 13 de malignos (14%. Foram significantes no diagnóstico de malignidade as seguintes características ultra-sonográficas: presença de sombra acústica posterior (p=0,0001, contornos irregulares (p=0,0007, ecos internos heterogêneos (p=0,0015 e diâmetro ântero-posterior (AP maior que o látero-lateral (LL (p<0,0001. A presença de halo ecogênico no tumor e a visibilização dos ligamentos de Cooper espessados não influenciaram o diagnóstico de malignidade nesse estudo. Conclusão: a ultra-sonografia é um método diagnóstico que pode ajudar na diferenciação de tumores sólidos benignos e malignos. Os contornos irregulares, os ecos internos heterogêneos, a sombra posterior e o diâmetro AP maior que o LL, quando presentes, apresentaram alta correlação com o exame anatomopatológico de câncer.

  4. Análisis de perforantes de la epigástrica inferior profunda con Angio TC 3D, Eco Doppler color y Doppler simple de ultrasonidos en colgajo DIEP: resultados preliminares Analysis of deep inferior epigastric perforating vessels with 3D CT angiography, color Doppler ultrasonography and Doppler in diep flaps: preliminary results

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    J. Castro García

    2008-09-01

    Full Text Available Nuestro objetivo es la validación de la Angio TC tridimensional como herramienta de planificación de los colgajos DIEP, comparándolo con el Doppler de ultrasonidos (US y eco Doppler color. Entre enero de 2006 y marzo de 2007 se realiza en 11 pacientes (13 DIEP un estudio comparativo prospectivo entre el Doppler de US, eco Doppler color y Angio TC con reconstrucción tridimensional, utilizando como dato de referencia los hallazgos intraoperatorios. En dicho proceso se localiza la mejor perforante que pueda servir como pedículo al colgajo DIEP en función de su localización, calibre, trayecto y relaciones anatómicas con respecto al músculo. La Angio TC con reconstrucción tridimensional, demuestra una especificidad del 100% (IC 95% 75.3-100 lo que le convierte en una prueba con un alto valor predictivo positivo y una excelente herramienta en la planificación de los colgajos de perforantes. El eco Doppler color determinó, que tan sólo en un 46,1% (IC 95% 19,2-74,9 de los pacientes, la perforante seleccionada por la prueba de forma preoperatoria, coincidía con la perforante elegida en quirófano. Con el Doppler de US, en un 30,8 % (IC 95% 9,1-61,4 de los colgajos estudiados, coincidía la mejor perforante escogida de forma preoperatoria, con los hallazgos obtenidos tras la disección del colgajo. En el presente estudio, la Angio TC tridimensional se ha mostrado como una técnica con una gran especificidad que proporciona valiosa información, sólo comparable con la disección anatómica y por delante de pruebas como el Doppler de ultrasonidos y el eco Doppler color.The aim of this report, is to validate the Angio-CT technique with three-dimentional reconstruction as a preoperative planning tool, after comparison with Doppler ultrasound and color- Duplex. Between january 2006 and march 2007, we studied 11 consecutive patients (13 DIEP in whom a prospective comparative followed up was performed comparing, the findings observed using

  5. Hiperecogenicidade dos vasos talâmicos no recém-nascido prematuro Hyperechogenicity of thalamic vessels in preterm newborn infants

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    Natália Paczko

    2002-09-01

    Full Text Available Objetivo: o presente estudo procura avaliar as possíveis patologias que se manifestam associadas à hiperecogenicidade dos vasos talâmicos na ultra-sonografia cerebral, e observar a freqüência com que ocorrem. Métodos: a amostra foi constituída de 206 recém-nascidos prematuros, nascidos no Hospital de Clínicas de Porto Alegre, no período de julho de 1998 a maio de 1999. Todos realizaram a ultra-sonografia cerebral na primeira semana de vida. Foram incluídos no estudo aqueles prematuros que necessitaram de internação hospitalar, e que tiveram o termo de consentimento informado assinado por um dos responsáveis. Foram excluídos aqueles cuja ultra-sonografia cerebral evidenciava sangramento cerebral e/ou malformações congênitas associadas, e os que evoluíram para óbito antes da realização do exame. Resultados: a ultra-sonografia cerebral levou à identificação de 65 recém-nascidos prematuros com hiperecogenicidade dos vasos talâmicos e de 141 recém-nascidos prematuros sem. Conclusão: a forma de apresentação do tipo pélvica ao nascimento, a maior idade gestacional, o maior peso do recém-nascido ao nascimento e a classificação grande para a idade gestacional foram fatores de risco para a ocorrência de hiperecogenicidade dos vasos talâmicos, enquanto a presença de hipertensão materna durante o período de gestação tendeu a ser fator de proteção. Os recém-nascidos que apresentaram crises convulsivas durante o período de internação hospitalar tiveram risco 3,2 vezes maior de ter hiperecogenicidade dos vasos talâmicos, quando comparados aos que não apresentaram crises convulsivas.Objective: the aim of this study is to evaluate possible pathologies associated with hyperechogenicity of thalamic vessels (HETV, which are found on brain ultrasounds (BUS, as well as to observe the frequency of their occurrence. Methods: the sample was composed of 206 preterm newborn infants at Hospital de Clíncas de Porto Alegre

  6. An ultra-high frequency boundary layer Doppler/interferometric profiler

    International Nuclear Information System (INIS)

    Van Baelen, J.S.

    1994-01-01

    The planetary boundary layer (PBL) is that portion of the earth's atmosphere that is directly influenced by the earth's surface. The PBL can be vigorously turbulent and range in depth from a few hundred meters to a few kilometers. Solar energy is primarily absorbed at the earth's surface and transmitted to the free atmosphere through boundary-layer processes. An accurate portrayal of these transfers within the PBL is crucial to understand and predict many atmospheric processes from pollutant dispersion to numerical weather prediction and numerical simulations of climate change. This paper describes and discusses wind profiling techniques, focusing on the newly developed radio acoustic sounding system (RASS), and reviews past efforts to measure flux within the PBL. A new UHF wind profiling radar, the UHF Doppler/Interferometric Boundary Layer Radar, for accurately measuring both mean and flux quantities, as well as wind divergence and acoustic wave propagation, is outlined

  7. Anomalias branquiais: revisão de 23 casos

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    Rogério Aparecido Dedivitis

    Full Text Available A anomalia branquial é a doença congênita mais comum vista pelo cirurgião de cabeça e pescoço. Vinte e três pacientes portadores de anomalias branquiais tratados no período de 1994 a 1997 foram revisados. O diagnóstico clínico foi documentado por ultra-sonografia e comprovado pelo exame histopatológico. Encontramos seis anomalias de primeiro arco (26%; 16 do segundo arco (69,5%; e uma do terceiro (4,5%. Não houve anomalia do quarto arco. Após um seguimento que variou de três a 43 meses, não houve caso de recidiva. A prevalência de anomalias do segundo arco é compatível com a literatura, porém, foi alta a incidência do primeiro arco. O emprego da técnica cirúrgica adequada, com a ressecção de todo o trajeto fistuloso, mostrou-se eficaz.

  8. Fatores maternos associados ao peso fetal estimado pela ultra-sonografia Maternal factors associated with fetal weight estimated by ultrasonography

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    Adriana Suely de Oliveira Melo

    2008-09-01

    Full Text Available OBJETIVO: avaliar o efeito de variáveis maternas, socioeconômicas e obstétricas, assim como a presença de incisuras na 20ª e na 24ª semana, sobre o peso fetal estimado no final da gravidez (36ª semana em gestantes atendidas pelo Programa Saúde da Família em uma cidade do interior do Nordeste do Brasil. MÉTODOS: estudo longitudinal incluindo 137 gestantes. As gestantes foram acompanhadas a cada quatro semanas para aferição das condições clínicas, socioeconômicas e obstétricas, incluindo o peso materno. As artérias uterinas foram avaliadas pelo Doppler na 20ª e 24ª semana, o peso fetal e o índice de líquido amniótico (ILA foram determinados na 36ª semana. O estado nutricional materno inicial foi determinado pelo índice de massa corpórea (IMC, classificando-se as gestantes como com baixo peso, eutróficas, com sobrepeso e obesas. O ganho ponderal durante a gestação foi avaliado de acordo com o estado nutricional inicial, sendo ao final do segundo e terceiro trimestre classificado em ganho ponderal insuficiente, adequado e excessivo. Foi realizada análise de variância para avaliar a associação do peso fetal estimado na 36ª semana com as variáveis preditoras, ajustada por regressão linear múltipla. RESULTADOS: observou-se associação entre peso fetal estimado na 36ª semana e idade da mãe (p=0,02, trabalho materno (p=0,02, estado nutricional inicial (p=0,04, ganho ponderal no segundo trimestre (p=0,01, presença de incisuras nas artérias uterinas (p=0,02 e ILA (p=0,007. Os principais fatores associados ao peso fetal estimado na 36ª semana, após a análise de regressão múltipla, foram: IMC no início da gravidez, ganho ponderal no segundo trimestre, ILA e tabagismo. CONCLUSÕES: o peso fetal no presente estudo associou-se positivamente ao estado nutricional materno inicial, ao ganho ponderal no segundo trimestre, ao volume do líquido amniótico e negativamente ao hábito de tabagismo.PURPOSE: to evaluate the

  9. Estimativa da gordura de cobertura ao abate, por ultra-som, em tourinhos Brangus e Nelore Prediction of backfat at slaughter, by ultrasound, in Nellore and Brangus young bulls

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    Saulo da Luz e Silva

    2004-04-01

    Full Text Available O objetivo deste trabalho foi verificar a viabilidade da utilização da ultra-sonografia para estimar a espessura de gordura na carcaça (EGSC no momento do abate. Foram confinados 24 machos inteiros Brangus e 24 Nelore com dietas contendo 20, 40, 60 ou 80% de concentrado. A área de olho de lombo (AOLU e a espessura de gordura (EGSU entre a 12ª e a 13ª costelas e a espessura de gordura sobre o músculo Biceps femoris (EGPU, foram obtidas com equipamento de ultra-som PieMedical Scanner 200 Vet com transdutor linear de 178 mm e guia acústica, a cada intervalo de aproximadamente 28 dias. Após 142 dias de confinamento, os animais foram abatidos e 24 h após foi obtida a EGSC. As correlações entre EGSU e EGSC foram de 0,19, 0,64, 0,74, 0,78, 0,82, 080 e 0,86, quando obtidas aos 0, 26, 53, 84, 109, 125 e 142 dias de confinamento. Equações de regressão múltipla entre raças para estimar a EGSC apresentaram R² = 0,10 e Sy,x = 2,04 quando realizadas 142 dias antes do abate e R² = 0,78 e Sy,x = 0,10 imediatamente antes do abate. Medidas de ultra-som podem ser úteis para classificar grupos de animais para abate em igual acabamento.The objective of this work was to verify the usefullness of ultrasound to estimate the carcass backfat thickness (EGSC at slaughter. Twenty four Brangus and 24 Nelore, intact males, were fed with diets containing 20, 40, 60 or 80% of concentrate. Ribeye area (AOLU and backfat thickness (EGSU between 12ª and 13ª ribs and the fat thickness over Biceps femoris muscle (EGPU were collected with a PieMedical Scanner 200 Vet equipment, with linear array transducer of 178 mm coupled with standoff guide, on intervals of approximately 28 days. After 142 days on fed, animals were slaughtered and the carcass backfat thickness (EGSC was taken, 24 hours after. The correlations between EGSU and EGSC were 0.19, 0.64, 0.74, 0.78, 0.82, 0.80 and 0.86 when taken at 0, 26, 53, 84, 109, 125 and 142 days on fed. Multiple regression

  10. Avaliação do ombro em pacientes portadores de espondilite anquilosante por meio de ultra-som Evaluation of the shoulder in patients with ankylosing spondylitis with ultrasound

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    Ciro Yoshida Junior

    2008-04-01

    Full Text Available OBJETIVO: Descrever as principais alterações nos ombros de pacientes portadores de espondilite anquilosante (EA por meio de ultra-som (US e correlacionar os achados de imagem com a idade e o tempo de doença. MÉTODOS: Foram selecionados 35 pacientes com diagnóstico clínico de EA. Os pacientes foram submetidos a exame de ultra-sonografia dos ombros, sendo avaliados os tendões do manguito rotador quanto à sua ecotextura e espessura, o tendão do bíceps, a articulação acromioclavicular, os tubérculos umerais, a bursa subacromial-subdeltóidea, e a face posterior da articulação glenoumeral. Foram colhidos dados de tempo de doença, presença de dor nos ombros e freqüência das alterações das estruturas avaliadas. Os dados foram comparados com a idade e o tempo de doença, utilizando-se teste qui-quadrado e teste t de Student. RESULTADOS: Foi observada prevalência de 20% de alterações no manguito rotador, sendo 10% de tendinose/calcificação tendínea e 10% de rupturas tendíneas. A espessura média dos tendões do manguito rotador foi de 5,8 mm. As alterações ósseas nos tubérculos do úmero ocorreram em 84,3% dos ombros e as alterações acromioclaviculares em 54,3% dos ombros. CONCLUSÃO: Não há modificação da espessura dos tendões do manguito rotador relacionadas com o tempo de doença. Os principais achados de US, que se correlacionam com o tempo de doença na EA, são alterações ósseas nos tubérculos umerais e na articulação acromioclavicular. Não houve relação entre tempo de doença e presença de lesão tendínea.PURPOSE: To describe shoulder involvement and its prevalence with ultrasound in patients with ankylosing spondylitis and correlate the findings with age and duration of disease. METHODS: Ultrasound scans of both shoulders were performed in thirty five selected patients with clinical diagnosis of ankylosing spondylitis. Rotator cuff texture and thickness were evaluated as well as the biceps tendon

  11. Sub-Doppler spectroscopy

    International Nuclear Information System (INIS)

    Hansch, T.W.

    1983-01-01

    This chapter examines Doppler-free saturation spectroscopy, tunable cw sources, and Doppler-free two-photon spectroscopy. Discusses saturation spectroscopy; continuous wave saturation spectroscopy in the ultraviolet; and two-photon spectroscopy of atomic hydrogen 1S-2S. Focuses on Doppler-free laser spectroscopy of gaseous samples. Explains that in saturation spectroscopy, a monochromatic laser beam ''labels'' a group of atoms within a narrow range of axial velocities through excitation or optical pumping, and a Doppler-free spectrum of these selected atoms is observed with a second, counterpropagating beam. Notes that in two-photon spectroscopy it is possible to record Doppler-free spectra without any need for velocity selection by excitation with two counterpropagating laser beams whose first order Doppler shifts cancel

  12. Ecocardiografia por Doppler tecidual no diagnóstico de rejeição após transplante cardíaco Ecocardiografía con Doppler tisular en el diagnóstico de rechazo después de transplante cardíaco Tissue doppler echocardiography in the diagnosis of heart transplantation rejection

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    Marcos Valério Coimbra Resende

    2011-07-01

    Full Text Available FUNDAMENTO: A biópsia endomiocárdica (BEM é o método padrão-ouro para o diagnóstico de rejeição celular (RC após transplante cardíaco (TC. OBJETIVO: Testar a hipótese de que o exame de imagem por Doppler tecidual (IDT pode detectar RC > 3A e agregar informação diagnóstica, comparado ao Doppler convencional. MÉTODOS: Cinquenta e quatro pacientes com TC foram submetidos à BEM e estudo ecocardiográfico através de IDT em até 24 horas. Comparamos os pacientes com TC e RC > 3A com pacientes com TC e RC 3A em 39/129 (30,2% das BEM. O melhor preditor isolado para o diagnóstico de RC foi a a'LAT, com sensibilidade de 76,3%, especificidade de 73,8% (p = 0,001. Na análise multivariada, a a'LAT (p = 0,001, a'SEP (p = 0,002, relação e'/a' LAT (p = 0,006, relação e'Mitral/ e'LAT (p = 0,014, SINF (p = 0,009 foram preditores de RC > 3A. Obtivemos um escore com sensibilidade de 88,2%, acurácia de 79,6%, e valor preditivo negativo de 92,9% para diagnosticar RC > 3A. O Doppler convencional (fluxo mitral e pulmonar venoso não foi relevante para predizer a RC > 3A. CONCLUSÃO: O estudo de IDT agregou informação diagnóstica para predizer RC > 3A quando comparado ao Doppler convencional. O modelo baseado em IDT pode ser tornar um método em potencial para detectar RC > 3A após TC.FUNDAMENTO: La biopsia endomiocárdica (BEM es el método gold standard para el diagnóstico de rechazo celular (RC después de transplante cardíaco (TC. OBJETIVO: Testear la hipótesis de que el examen de imagen con Doppler tisular (IDT puede detectar RC > 3A y agregar información diagnóstica, comparado al Doppler convencional. MÉTODOS: Cincuenta y cuatro pacientes con TC fueron sometidos a BEM y estudio ecocardiográfico a través de IDT en hasta 24 horas. Comparamos los pacientes con TC y RC > 3A con pacientes con TC y RC 3A en 39/129 (30,2% de las BEM. El mejor predictor aislado para el diagnóstico de RC fue la a'LAT, con sensibilidad de 76

  13. Doppler Tomography

    Science.gov (United States)

    Marsh, T. R.

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the accretion disc or stream. I discuss all of these and finish with some musings on possible future directions for the method. At the end I include a tabulation of Doppler maps published in refereed journals.

  14. Tratamento de gestação cervical viável com aplicação intra-amniótica de metotrexato: relato de um caso Treatment of a viable cervical pregnancy with a single-intraamniotic methotrexate injection: a case report

    Directory of Open Access Journals (Sweden)

    José Juvenal Linhares

    2006-10-01

    Full Text Available Gestação cervical é uma condição rara, em que ocorre implantação do ovo no canal cervical distendendo-o à medida que cresce. Corresponde a menos de 1% de todas as gestações ectópicas. A hemorragia indolor é sua característica clínica habitual e ao exame físico visualiza-se um colo hipertrófico e vascularizado, com tecido saindo pelo orifício externo do colo. Ultra-sonografia pode ser usada para complementar o diagnóstico, mostrando a presença do saco gestacional. Relatamos um caso de tratamento bem sucedido de gestação cervical viável de sete semanas. Morte fetal foi conseguida com uma injeção intra-amniótica única de metotrexato (25 mg guiada por ultra-sonografia transvaginal. Metotrexato sistêmico em dose única intramuscular (50 mg/m² foi associado. O tratamento conservador da gestação cervical com metotrexato foi efetivo e seguro.Cervical pregnancy is a rare condition in which the egg is implanted in the cervical canal causing it to distend as the egg grows. Cervical pregnancy constitutes less than 1% of all ectopic pregnancies. Painless hemorrhage is a habitual clinical characteristic and on physical examination a very vascularized hypertrophic cervix is observed with a tissue surpassing the external orifice. Ultrasonography may be used as a complementary diagnostic tool to show directly the presence of a gestational sac. A successful management of a viable seven-week gestation cervical pregnancy is reported herein. Feticide was performed with a single intraamniotic methotrexate injection (25 mg guided by transvaginal ultrasonography. Systemic methotrexate in a single dose intramuscular (50 mg/m² was associated. The conservative management of cervical ectopic pregnancy with methotrexate was effective and safe.

  15. Gamma-ray induced doppler broadening

    International Nuclear Information System (INIS)

    Robinson, S.J.

    1992-01-01

    The ultra high resolving power of the GAMS4 double-flat crystal spectrometer (M.S. Dewey et al Nucl. Instrum. Methods A 284 (1989) 151.) has been used to observe the Doppler broadening of gamma-rays emitted by nuclei recoiling at speeds as low as 10 -6 c. Such recoils may be induced by the previous emission of gamma-radiation following thermal neutron capture. If the population mechanism of an excited state is known (or can be approximated) and the slowing down mechanism can be modeled, then this technique can be used to extract the lifetime of excited nuclear states. The combination of this technique and the neutron capture reaction allows the study of states which cannot necessarily be accessed by other means. This has allowed the resolution of a number of long standing questions in low-spin nuclear structure. The basis of the technique is discussed and a number of examples given

  16. Comparisons between PW Doppler system and enhanced FM Doppler system

    DEFF Research Database (Denmark)

    Wilhjelm, Jens E.; Pedersen, P. C.

    1995-01-01

    This paper presents a new implementation of an echo-ranging FM Doppler system with improved performance, relative to the FM Doppler system reported previously. The use of long sweeps provides a significant reduction in peak to average power ratio compared to pulsed wave (PW) emission. A PW Doppler...... system exploits the direct relationship between arrival time of the received signal and range from the transducer. In the FM Doppler systems, a similar relationship exists in the spectral domain of the demodulated received signals, so that range is represented by frequency. Thus, a shift in location...... of moving scatterers between consecutive emissions corresponds to a frequency shift in the spectral signature. The improvement relative to the earlier version of the FM Doppler system is attained by utilizing cross-correlation of real spectra rather than of magnitude spectra for assessing flow velocity...

  17. Doppler optical cardiogram gated 2D color flow imaging at 1000 fps and 4D in vivo visualization of embryonic heart at 45 fps on a swept source OCT system.

    Science.gov (United States)

    Mariampillai, Adrian; Standish, Beau A; Munce, Nigel R; Randall, Cristina; Liu, George; Jiang, James Y; Cable, Alex E; Vitkin, I A; Yang, Victor X D

    2007-02-19

    We report a Doppler optical cardiogram gating technique for increasing the effective frame rate of Doppler optical coherence tomography (DOCT) when imaging periodic motion as found in the cardiovascular system of embryos. This was accomplished with a Thorlabs swept-source DOCT system that simultaneously acquired and displayed structural and Doppler images at 12 frames per second (fps). The gating technique allowed for ultra-high speed visualization of the blood flow pattern in the developing hearts of African clawed frog embryos (Xenopus laevis) at up to 1000 fps. In addition, four-dimensional (three spatial dimensions + temporal) Doppler imaging at 45 fps was demonstrated using this gating technique, producing detailed visualization of the complex cardiac motion and hemodynamics in a beating heart.

  18. Gamma-ray induced Doppler broadening and the determination of lifetimes of excited nuclear states

    International Nuclear Information System (INIS)

    Boerner, H.G.; Jolie, J.; Robinson, S.J.; Kessler, E.G.; Dewey, S.M.; Greene, G.; Deslattes, R.; Ulbig, S.; Lieb, K.P.; Casten, R.F.; Krusche, B.; Cizewski, J.A.

    1990-01-01

    Measurements of lifetimes of excited states in nuclei yield crucial information for sensitive tests of nuclear models. Here a novel method will be discussed which involves the GRID (Gamma Ray Induced Doppler broadening) technique, in which Doppler broadening is observed in a transition from a nucleus recoiling from the emission of a previous gamma ray. As the recoil energy is extremely small, ultra-high energy resolving power has to be used. To date all such experiments have been carried out at ILL using the GAMS4 double flat crystal spectrometer which is operated in a NIST-ILL collaboration. The method can be used for all lifetimes below a few picoseconds. The wide range of applicability, together with the very exhaustive set of data often obtained, is an advantage with respect to many other methods. The characteristic features of GRID will be discussed using some selected examples. 21 refs., 8 figs

  19. Ultra-sonografia mamária: avaliação dos critérios ecográficos na diferenciação das lesões mamárias Breast ultrasound: evaluation of echographic criteria for differentiation of breast lesions

    Directory of Open Access Journals (Sweden)

    Maria Julia Gregorio Calas

    2007-02-01

    Full Text Available OBJETIVO: O câncer de mama é uma das causas mais importantes de mortalidade feminina. Na busca do diagnóstico cada vez mais precoce, a associação de métodos diagnósticos tem sido utilizada com êxito, tendo grande participação a ultra-sonografia mamária diagnóstica e intervencionista. Este trabalho tem como objetivos: identificar os critérios ecográficos mais relacionados com benignidade e malignidade e avaliar as propriedades das características ecográficas, verificando o seu poder de predição de malignidade. MATERIAIS E MÉTODOS: Os critérios morfológicos ecográficos utilizados nas descrições das imagens foram: forma, limites, contorno, ecogenicidade, ecotextura, ecotransmissão, orientação e sinais secundários. A validação foi buscada em 450 imagens ecográficas, comparadas aos resultados de seguimento ou de histopatologia de peça cirúrgica. RESULTADOS: Os principais critérios de benignidade foram: forma definida, contorno regular, limites precisos, lesões isoecóicas ao tecido adiposo, ecotextura homogênea e orientação horizontal. Os critérios mais característicos de malignidade foram: forma indefinida, contorno irregular, limites parcialmente precisos e lesões hipoecóicas. O contorno irregular apresentou a maior sensibilidade (92,7% e o maior valor preditivo negativo (98,2% para malignidade, a orientação vertical apresentou a maior especificidade (99,3%, e a forma indefinida, o maior valor preditivo positivo (91,0%. CONCLUSÃO: O método padronizado para a caracterização e descrição das imagens ultra-sonográficas mamárias apresentado resultou em uniformidade e otimização dos laudos, viabilizando as condutas mais adequadas.OBJECTIVE: Breast cancer is one of the most important causes of death in women. The association of different diagnostic methods has been successfully employed as a means to enhance early diagnosis. In this scenario, the interventional and diagnostic breast ultrasound has

  20. Analisis experimental de la propagacion en redes de area corporal para la banda de ultra wideband. experimental characterization of the propagation in ultra wideband body area networks

    Science.gov (United States)

    Garcia Serna, Ruben Gregorio

    Diferentes dispositivos capaces de obtener informacion sobre parametros fisiologicos, cinematicos o contextuales del cuerpo pueden interconectarse de manera inalambrica dando lugar a las denominadas Redes de Area Corporal Inalambricas (WBAN, Wireless Body Area Networks). De entre las posibles tecnologias para establecer los enlaces, Ultra Wideband (UWB) esta captando cada vez un mayor interes debido a caracteristicas tales como el bajo nivel de potencia de transmision requerido (bajo nivel de exposicion a campos electromagneticos), el alto ancho de banda disponible y la alta resolucion temporal/espacial. El diseno de sistemas centrados en el cuerpo requiere de modelos de canal que describan de manera precisa la propagacion de senales en este tipo de entornos. Esta tesis se plantea con el objetivo de contribuir al estudio experimental de la propagacion en sistemas centrados en el cuerpo operando en la banda UWB. En primer lugar, se presenta un marco introductorio a las redes WBAN, sus elementos constitutivos, bandas de frecuencia, estandarizacion y modelos de canal. Ademas, se introducen los fundamentos de la tecnologia UWB y sus aplicaciones en este area. Seguidamente, se analiza en terminos de las perdidas de propagacion y la dispersion de retardo la propagacion en el canal off-body entre un transmisor fijo y un dispositivo receptor colocado sobre la superficie del cuerpo de un sujeto. Se considera la influencia de diferentes aspectos, tales como el entorno de medidas, la posicion de colocacion de una antena sobre el cuerpo y la postura adoptada por un sujeto. Finalmente, se analiza el canal de propagacion in-body considerando el movimiento relativo entre dos dispositivos causado por efecto de la respiracion. Las condiciones de propagacion en el interior del cuerpo se emulan por medio de un phantom liquido para UWB y la caracterizacion se plantea tanto en frecuencia, en terminos del modelado de la forma y el ensanchamiento del espectro Doppler, como en tiempo, por

  1. A model for post-occlusive reactive hyperemia as measured with laser-Doppler perfusion monitoring

    NARCIS (Netherlands)

    de Mul, FFM; Morales, F; Smit, AJ; Graaff, R

    To facilitate the quantitative analysis of post-occlusive reactive fiyper emia (POR11), measured with laser-Doppler perfusion monitoring (LDPM) on extremities, we present a flow model for the dynamics of the perfusion of the tissue during PORH, based on three parameters: two time constants (tau(1)

  2. Valor preditivo do resultado fetal da dopplervelocimetria de ducto venoso entre a 11ª e a 14ª semanas de gestação Predictive value for fetal outcome of Doppler velocimetry of the ductus venosus between the 11th and the 14th gestation week

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Gollo

    2008-01-01

    Full Text Available OBJETIVO: estudar o valor da dopplervelocimetria do ducto venoso (DV entre a 11º e a 14º semanas de gestação, associado à medida da translucência nucal (TN, na detecção de resultado fetal adverso. MÉTODOS: foram estudados 1.268 fetos consecutivamente. Em 56 casos, realizou-se estudo citogenético no material obtido, por meio de biópsia de vilosidade coriônica e, em 1.181 casos, o resultado teve como base o fenótipo do recém-nascido. Todos os fetos foram submetidos, além da ultra-sonografia de rotina, à medida da TN e à dopplervelocimetria do DV. Trata-se de um estudo transversal e prospectivo. Foram calculados e analisados, para fins de prevalência e índices de acurácia: sensibilidade, especificidade, valor preditivo positivo (VPP, valor preditivo negativo (VPN, probabilidade de falso-positivo (PFP, probabilidade de falso-negativo (PFN, razão de probabilidade positiva e razão de probabilidade negativa. RESULTADOS: do total de 1.268 fetos, foram selecionados para análise 1.183 casos. Deste total, 1.170 fetos eram normais (98,9% e 13 fetos tiveram resultado fetal adverso ao nascimento (1,1% - incluindo morte fetal (trissomia 21 e 22 em dois casos, síndrome genética (Nooman em um caso, fetos polimalformados em dois casos, cardiopatia em três casos e outros defeitos estruturais em cinco casos. A prevalência do DV alterado (onda A zero/reversa na população estudada foi de 14 casos (1,2%, com taxa de falso-positivo de 0,7%. CONCLUSÕES: há correlação significativa entre alteração da dopplervelocimetria do DV e a medida da TN, como marcadores ultra-sonográficos de primeiro trimestre, na detecção de resultado fetal adverso, especialmente para malformações graves. O Doppler do DV foi capaz de diminuir o resultado falso-positivo, comparativamente ao uso isolado da TN, melhorando consideravelmente o VPP do teste.PURPOSE: to study the value of Doppler velocimetry of the ductus venosus, between the 11th and 14th weeks of

  3. Planetary Radio Interferometry and Doppler Experiment (PRIDE) for Planetary Atmospheric Studies

    Science.gov (United States)

    Bocanegra Bahamon, Tatiana; Cimo, Giuseppe; Duev, Dmitry; Gurvits, Leonid; Molera Calves, Guifre; Pogrebenko, Sergei

    2015-04-01

    The Planetary Radio Interferometry and Doppler Experiment (PRIDE) is a technique that allows the determination of the radial velocity and lateral coordinates of planetary spacecraft with very high accuracy (Duev, 2012). The setup of the experiment consists of several ground stations from the European VLBI Network (EVN) located around the globe, which simultaneously perform Doppler tracking of a spacecraft carrier radio signal, and are subsequently processed in a VLBI-style in phase referencing mode. Because of the accurate examination of the changes in phase and amplitude of the radio signal propagating from the spacecraft to the multiple stations on Earth, the PRIDE technique can be used for several fields of planetary research, among which planetary atmospheric studies, gravimetry and ultra-precise celestial mechanics of planetary systems. In the study at hand the application of this technique for planetary atmospheric investigations is demonstrated. As a test case, radio occultation experiments were conducted with PRIDE having as target ESA's Venus Express, during different observing sessions with multiple ground stations in April 2012 and March 2014. Once each of the stations conducts the observation, the raw data is delivered to the correlation center at the Joint Institute for VLBI in Europe (JIVE) located in the Netherlands. The signals are processed with a high spectral resolution and phase detection software package from which Doppler observables of each station are derived. Subsequently the Doppler corrected signals are correlated to derive the VLBI observables. These two sets of observables are used for precise orbit determination. The reconstructed orbit along with the Doppler observables are used as input for the radio occultation processing software, which consists of mainly two modules, the geometrical optics module and the ray tracing inversion module, from which vertical density profiles, and subsequently, temperature and pressure profiles of Venus

  4. Ultra-High-Energy Cosmic Ray Acceleration by Magnetic Reconnection in Newborn Pulsars

    OpenAIRE

    Pino, E. M. de Gouveia Dal; Lazarian, A.

    2000-01-01

    Investigamos la posibilidad de que los rayos c osmicos ultra energ eticos (UHECR) observados arriba del l mite GZK sean protones acelerados en zonas de reconecci on localizadas sobre la magnet osfera de pulsares de milisegundos reci en formados por un colapso inducido por acreci on (AIC).

  5. Metaplasia óssea e esterilidade primária

    Directory of Open Access Journals (Sweden)

    Reggiani Celeste P. Demeterco

    2001-01-01

    Full Text Available A metaplasia óssea do endométrio é uma condição rara e pode ser explicada por uma neoformação no endométrio, com deposição de sais de cálcio. Entretanto, a situação mais comum é a história prévia de abortamento com permanência de ossículos na cavidade uterina. Foi relatado um caso de ossificação endometrial em uma mulher de 31 anos, sem gravidez prévia ou história de aborto, apresentando dismenorréia e infertilidade. A ultra-sonografia pélvica mostrou área hiperecóica no fundo da cavidade uterina. A histeroscopia foi realizada e uma imagem sugestiva de tecido ósseo foi encontrada. Este tecido foi retirado e a histopatologia confirmou a ossificação endometrial.

  6. Experimental intoxication of pregnant goats with Tetrapterys multiglandulosa A. Juss. (Malpighiaceae Intoxicação experimental por Tetrapterys multiglandulosa A. Juss. (Malpighiaceae em cabras gestantes

    Directory of Open Access Journals (Sweden)

    M.M. Melo

    2001-02-01

    ês dias. Foi detectada por ultra-sonografia morte fetal e, ao exame clínico, presença de secreção vaginal com subseqüente aborto. Os animais dos grupos I e II (tradados abortaram no terceiro e no final do segundo mês de gestação, respectivamente, e juntos com os do grupo III (controle foram sacrificados e submetidos a exames anátomo-histopatológicos. Pela histopatologia observou-se placentite focal com grande quantidade de células trofoblásticas binucleadas em apoptose, além de endometrite focal aguda e petéquias vulvo-vaginais. Todos os fetos abortados estavam subdesenvolvidos quando comparados com os fetos do grupo III (controle devido à malnutrição, pois nenhum defeito congênito pôde ser notado. Vários fetos abortados mostravam alguma autólise, pois sua morte precedia em cinco e três dias o aborto, nos tratamentos I e II, respectivamente. As lesões fetais observadas foram hemorragias difusas ou focais na pele, meninges e serosa visceral.

  7. Improved algorithms for the calculation of resolved resonance cross sections with applications to the structural Doppler effect in fast reactors

    International Nuclear Information System (INIS)

    Hwang, R.N.; Toppel, B.J.; Henryson, H. II.

    1980-10-01

    Motivated by a need for an economical yet rigorous tool which can address the computation of the structural material Doppler effect, an extremely efficient improved RABANL capability has been developed utilizing the fact that the Doppler broadened line shape functions become essentially identical to the natural line shape functions or Lorentzian limits beyond about 100 Doppler widths from the resonance energy, or when the natural width exceeds about 200 Doppler widths. The computational efficiency has been further enhanced by preprocessing or screening a significant number of selected resonances during library preparation into composition and temperature independent smooth background cross sections. The resonances which are suitable for such pre-processing are those which are either very broad or those which are very weak. The former contribute very little to the Doppler effect and their self-shielding effect can readily be averaged into slowly varying background cross section data, while the latter contribute very little to either the Doppler or to self-shielding effects. To illustrate the accuracy and efficiency of the improved RABANL algorithms and resonance screening techniques, calculations have been performed for two systems, the first with a composition typical of the STF converter region and the second typical of an LMFBR core composition. Excellent agreement has been found for RABANL compared to the reference Monte Carlo solution obtained using the code VIM, and improved results have also been obtained for the narrow resonance approximation in the ultra-fine-group option of MC 2 -2

  8. Desarterialização transanal guiada por doppler associada ao reparo anorretal na doença hemorroidária: a técnica do THD Transanal desarterialization guided by Doppler associated to anorectal repair in hemorrhoids: THD technic

    Directory of Open Access Journals (Sweden)

    Carlos Walter Sobrado-Junior

    2012-12-01

    Full Text Available INTRODUÇÃO: O tratamento cirúrgico para hemorroidas deve ter indicação individual e baseia-se no sintoma predominante (sangramento ou prolapso, na gravidade da doença e na presença ou ausência de componente externo (plicoma. Cabe ao cirurgião conhecer as mais variadas técnicas para que possa encontrar o tratamento mais adequado caso a caso. TÉCNICA: O procedimento THD consiste na ligadura alta seletiva e guiada por Doppler de até seis ramos arteriais submucosos que irrigam as hemorroidas, levando à sua desarterialização, associada à correção do prolapso (reparo anorretal ou lifting. Utiliza equipamento e kit especiais. CONCLUSÃO: A técnica do THD tem mostrado bons resultados iniciais. Por ser técnica cirúrgica em que se respeita a anatomia, ela age diretamente sobre a fisiopatologia da afecção e corrige suas principais consequências, ela parece bastante promissora. Sua aplicação inicial pode ser nos pacientes com doença hemorroidária de II grau, que tenham indicação de tratamento cirúrgico, e de III e IV graus, nestes últimos, podendo ser associada à ressecção de plicomas.INTRODUCTION: Surgical treatment for hemorrhoids should be indicated individually and is based on the predominant symptom (bleeding or prolapse, severity of disease and the presence or absence of external component (plicoma. Surgeons must choose among varied techniques the one suitable for each case. TECHNIC: The THD procedure consists of Doppler guided high ligation, selective to up six submucosal arterial branches that supply the hemorrhoids, leading to its desarterialization associated with prolapse repair (anorectal repair or lifting. It uses special equipment and kit. CONCLUSION: THD technique has shown good initial results. Because surgical technique respects the anatomy, it acts directly on the pathophysiology of the disease and corrects its principal consequences; it looks quite promising. Its initial application may be in patients

  9. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    International Nuclear Information System (INIS)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions

  10. Dual-Doppler Feasibility Study

    Science.gov (United States)

    Huddleston, Lisa L.

    2012-01-01

    When two or more Doppler weather radar systems are monitoring the same region, the Doppler velocities can be combined to form a three-dimensional (3-D) wind vector field thus providing for a more intuitive analysis of the wind field. A real-time display of the 3-D winds can assist forecasters in predicting the onset of convection and severe weather. The data can also be used to initialize local numerical weather prediction models. Two operational Doppler Radar systems are in the vicinity of Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS); these systems are operated by the 45th Space Wing (45 SW) and the National Weather Service Melbourne, Fla. (NWS MLB). Dual-Doppler applications were considered by the 45 SW in choosing the site for the new radar. Accordingly, the 45th Weather Squadron (45 WS), NWS MLB and the National Aeronautics and Space Administration tasked the Applied Meteorology Unit (AMU) to investigate the feasibility of establishing dual-Doppler capability using the two existing systems. This study investigated technical, hardware, and software requirements necessary to enable the establishment of a dual-Doppler capability. Review of the available literature pertaining to the dual-Doppler technique and consultation with experts revealed that the physical locations and resulting beam crossing angles of the 45 SW and NWS MLB radars make them ideally suited for a dual-Doppler capability. The dual-Doppler equations were derived to facilitate complete understanding of dual-Doppler synthesis; to determine the technical information requirements; and to determine the components of wind velocity from the equation of continuity and radial velocity data collected by the two Doppler radars. Analysis confirmed the suitability of the existing systems to provide the desired capability. In addition, it is possible that both 45 SW radar data and Terminal Doppler Weather Radar data from Orlando International Airport could be used to alleviate any

  11. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Science.gov (United States)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    Aim: To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions. PMID:22223940

  12. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Directory of Open Access Journals (Sweden)

    Sumit Goel

    2011-01-01

    Full Text Available Aim: To evaluate the efficacy of ultrasonography (USG with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas. There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions.

  13. Physics of Eclipsing Binaries: Modelling in the new era of ultra-high precision photometry

    OpenAIRE

    Pavlovski, K.; Bloemen, S.; Degroote, P.; Conroy, K.; Hambleton, Kelly; Giammarco, J.M.; Pablo, H.; Prša, A.; Tkachenko, A.; Torres, G.

    2013-01-01

    Recent ultra-high precision observations of eclipsing binaries, especially data acquired by the Kepler satellite, have made accurate light curve modelling increasingly challenging but also more rewarding. In this contribution, we discuss low-amplitude signals in light curves that can now be used to derive physical information about eclipsing binaries but that were unaccessible before the Kepler era. A notable example is the detection of Doppler beaming, which leads to an increase in flux when...

  14. Comparison of power Doppler and color Doppler ultrasonography in the detection of intrasticular blood flow of normal infants

    International Nuclear Information System (INIS)

    Shin, Sung Ran; Lee, Ho Kyoung; Lee, Won Gyun; Youk, Dong Joon; Rho, Taek Soo; Lee, Min Jin; Lee, Sang Chun

    1999-01-01

    To compare color Doppler ultrasonography (US) and power Doppler US in the detection of intratesticular blood flow in normal infants and to asses the symmetry of blood flow. Testicular blood flow was assessed prospectively in 100 testes of 50 infants with both power and color Doppler US. We compared the power Doppler with color Doppler to detect intratesticular blood. When the flow was detected, intratesticular blood flow was graded as follows: grade 1: single intratesticular Doppler signal ; grade 2: multiple intratesticular Doppler signals. The symmetry of intratesticular flow was assessed by using the same method. Intratesticular flow was detected in 72 (72%) and 68 (68%) testes on power and color Doppler US, respectively. In 76 testes (76%), intratesticular flow was detected in either one or both techniques. On power Doppler US, grade 1 was seen in 40 tests and grade 2 in 32 testes. On color Doppler US, grade 1 was noted in 52 testes and grade 2 in 16 testes. Testicular blood flow was symmetric on both power and color Doppler US in each patient. There was no difference between power Doppler and color Doppler ultrasonography in detecting intratesticular blood flow in normal infants.

  15. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  16. Comparação dos métodos de imagem no diagnóstico dos tumores renais e calcificações nestas neoplasias Comparison of imaging methods for diagnosis of renal tumors and their calcifications

    Directory of Open Access Journals (Sweden)

    Sergio Marrone Ribeiro

    2004-12-01

    Full Text Available OBJETIVO: Tentar estabelecer uma metodologia no diagnóstico e conduta dos pacientes com massas renais sólidas e complexas, comparando os custos e benefícios dos diferentes métodos de diagnóstico por imagem. Procuramos avançar no diagnóstico diferencial entre lesões benignas e malignas, particularmente através da investigação das calcificações tumorais. MÉTODOS: Realizamos um estudo prospectivo em 31 pacientes portadores de massas renais sólidas ou complexas, todos eles submetidos à ultra-sonografia abdominal (US, ultra-sonografia doppler da massa renal (US Dop, tomografia computadorizada (TC e ressonância magnética (RM. RESULTADOS: Encontramos 28 pacientes com massas malignas e três com massas benignas. Entre os 28 pacientes com lesões malignas, 17 mostraram calcificações pela TC; 16 deles calcificações do tipo central e um calcificação do tipo curvilinear periférica pura (casca de ovo. A urografia excretora (UGE mostrou uma taxa de detecção para calcificações significantemente menor que a US e a TC. Massas benignas e malignas apareceram como descrito na literatura, com o US, TC e RM mostrando alta sensibilidade e especificidade no diagnóstico dos tumores renais. A exceção foi na US Dop, onde nós obtivemos menor sensibilidade para a caracterização de fluxo tumoral maligno. CONCLUSÕES: Foi surpreendente verificar que a TC revelou calcificações centrais em 51,6% dos pacientes desta série, todas elas em lesões malignas, quando a literatura refere uma freqüência de calcificações entre 8% e 22% dos carcinomas de células renais, em estudos utilizando radiografias simples do abdômen e UGE. Este achado é de grande importância quando consideramos que estas calcificações ocorrem particularmente em neoplasias malignas. Como resultado da comparação dos diferentes métodos de diagnóstico por imagem, nós propomos uma metodologia para adequada investigação dos tumores renais.BACKGROUND: To establish the

  17. Refração atmosferica nas medidas Doppler

    OpenAIRE

    Oliveira, Leonardo Castro de

    1990-01-01

    Orientador: Jose Bittencourt de Andrade Dissertação (mestrado) - Universidade Federal do Parana. Setor de Tecnologia Resumo: Esta dissertação tem por objetivo realizar investigações referentes à refração atmosférica nas medidas Doppler. São considerados quatro modelos para correção troposférica, e o modelo de duas frequências para a correção da refração ionosférica . São também testados de diferentes fontes de dados meteorológicos. Todos os testes são feitos utilizando-se o programa GEO...

  18. Gallblader varices in children with portal cavernoma: duplex-Doppler and color Doppler ultrasound studies

    International Nuclear Information System (INIS)

    Muro, D.; Sanguesa, C.; Lopez, A.

    1998-01-01

    To determine the prevalence of varices in the gallbladder wall, observed by duplex-Doppler and color Doppler ultrasound, in children with cavernoma of the portal vein. Nineteen patients with portal hypertension were studied prospectively by duplex-Doppler and color Doppler ultrasound: 12 of the patients had developed a cavernoma of the portal vein. The presence of peri vesicular varices was assessed in the group of patients with portal cavernoma. Duplex-Doppler and color Doppler ultrasound disclosed the presence of varices in gallbladder wall in nine of the 12 patients (75%). The varices appeared as anechoic and serpiginous areas, and Doppler ultrasound revealed slowed venous flow. However, the three patients in whom gallbldder varices were not detected presented collateral gastric ciculation and spontaneous splenorenal shunt. Gallbladder varices are common in children with portal vein cavernoma; they present hepatopetal flow. Their developments is not related to the size of the portal cavernoma, the presence of spontaneous portosystemic shunts, or endoscopic obliteration of gastric and esophageal varices. The detection of gallbladder varices in patients with portal hypertension who are to undergo biliary surgery is highly important for the surgeon, helping to avoid perioperative complications. (Author) 15 refs

  19. Imaging observations of nighttime mid-latitude F-region field-aligned irregularities by an MU radar ultra-multi-channel system

    Directory of Open Access Journals (Sweden)

    S. Saito

    2008-08-01

    Full Text Available Mid-latitude F-region field-aligned irregularities (FAIs were studied by using the middle-and-upper atmosphere (MU radar ultra-multi-channel system with the radar imaging technique. On 12 June 2006, F-region FAI echoes with a period of about one hour were observed intermittently. These echoes were found to be embedded in medium-scale traveling ionospheric disturbances (MSTIDs observed as variations of total electron content (TEC. The echoes drifting away from (toward the radar were observed in the depletion (enhancement phase of the MSTID. The Doppler velocity of the echoes is consistent with the range rates in the the range-time-intensity (RTI maps. Fine scale structures with a spatial scale of 10 km or less were found by the radar imaging analysis. Those structures with positive Doppler velocities (moving away from the radar appeared to drift north- (up- westward, and those with negative Doppler velocities south- (down- eastward approximately along the wavefronts of the MSTID. FAIs with positive Doppler velocities filling TEC depletion regions were observed.

  20. Tratamento cirúrgico dos insulinomas -- estudo de 59 casos Surgical treatment of insulinoma. Study of 59 cases

    Directory of Open Access Journals (Sweden)

    M.C.C. Machado

    1998-06-01

    Full Text Available Após a confirmação clínica e laboratorial de hiperinsulinismo, o principal problema consiste na localização precisa da lesão no parênquima pancreático, propiciando tratamento cirúrgico adequado. OBJETIVO: Analisar os métodos utilizados para o diagnóstico e localização pré e intra-operatório dos insulinomas, bem como as técnicas e os resultados do tratamento cirúrgico. MÉTODOS: Foram estudados 59 casos consecutivos de insulinoma submetidos a intervenção cirúrgica. Cada um dos métodos utilizados para a localização pré-operatória dessas lesões foi avaliado quanto à sua eficiência em confronto com os achados intra-operatórios. A palpação do pâncreas, isoladamente ou associada à ultra-sonografia intra-operatória, como métodos de localização dos insulinomas, foi também estudada. Os tipos de intervenção cirúrgica foram analisados quanto aos seus resultados imediatos e tardios. RESULTADOS: Dos 59 insulinomas, 55 eram benignos e quatro, malignos. Dos métodos utilizados para a localização pré-operatória, a ultra-sonografia foi eficiente em 28,1% dos casos, a tomografia computadorizada em 25%, a ultra-sonografia endoscópica em 27,2%, a arteriografia seletiva em 54,1% e a colheita de amostras de sangue portal para dosagem de insulina em 94,4% dos casos. A palpação bidigital, durante a intervenção cirúrgica, localizou as lesões em 54/55 casos (98,2%. A ultra-sonografia intra-operatória foi decisiva em apenas um caso. Cinco doentes apresentavam neoplasia endócrina múltipla tipo I e em todos as lesões pancreáticas eram múltiplas. Foram efetuadas 29 enucleações e 32 ressecções pancreáticas nos doentes com lesões benignas. Os doentes com lesões malignas foram submetidos a ressecções pancreáticas e quimioterapia. Não houve mortalidade, porém observaram-se complicações (fístulas em 29/59 casos. Os resultados foram bons em 98,1% dos doentes com lesões benignas. Apenas um dos doentes com

  1. Estimativa do Peso Fetal: Comparação Entre um Método Clínico e a Ultra-Sonografia

    OpenAIRE

    Cury,Alexandre Faisal; Garcia,Sidney A. L.

    1998-01-01

    Objetivo: avaliar a validade da estimativa do peso fetal por método baseado na altura uterina - regra de Johnson. Métodos: foram estudadas 101 gestantes e seus recém-nascidos (RN), estimando-se o peso fetal pela utilização da regra de Johnson adaptada, que consiste em aplicação clínica de modelo matemático para cálculo do peso fetal baseado na altura uterina e na altura da apresentação fetal. O peso estimado foi obtido no dia do parto e foi comparado com o peso observado ao nascer, que consti...

  2. Doppler evaluation of valvular stenosis

    International Nuclear Information System (INIS)

    Kisslo, J.; Krafchek, J.; Adams, D.; Mark, D.B.

    1986-01-01

    One of the reasons why use of Doppler echocardiography is growing rapidly is because of its utility in detecting the presence of valvular stenosis and in estimating its severity. Detection of the presence of stenotic valvular heart disease using Doppler echocardiography was originally described over 10 years ago. It has been demonstrated that Doppler blood velocity data could be used to estimate the severity of a stenotic lesion. This chapter discusses the evaluation of valvular stenois using Doppler

  3. Evolução das lesões histológicas e ultra-estruturais no fígado de ovinos e bovinos experimentalmente intoxicados por Myoporum laetum

    OpenAIRE

    Bonel-Raposo Josiane; Driemeier David; Barros Severo Sales; Gevehr-Fernandes Cristina

    2003-01-01

    Amostras de Myoporum laetum foram colhidas durante a primavera e verão e administradas a cinco ovinos e seis bovinos em doses únicas de 20 e 30 g/kg. Biópsias hepáticas foram colhidas antes (controles) e 1, 3 e 7 dias após a dosagem da planta. Estas biópsias foram analisadas histológica e ultra-estruturalmente. Os sinais clínicos, em ovinos, caracterizaram-se, especialmente, por depressão, diminuição dos movimentos ruminais, fezes ressequidas, tenesmo, ranger de dentes, dispnéia e lesões típi...

  4. The Cognitive Doppler.

    Science.gov (United States)

    Kozoil, Micah E.

    1989-01-01

    Discusses the learning needs of students in the concrete operational stage in mathematics. Identifies the phenomenon of reduced cognitive performance in an out-of-class environment as the "Cognitive Doppler." Suggests methods of reducing the pronounced effects of the Cognitive Doppler by capitalizing on the students' ability to memorize…

  5. Doppler ultrasound exam of an arm or leg

    Science.gov (United States)

    Peripheral vascular disease - Doppler; PVD - Doppler; PAD - Doppler; Blockage of leg arteries - Doppler; Intermittent claudication - Doppler; Arterial insufficiency of the legs - Doppler; Leg pain and ...

  6. Doppler flowmetry in preeclampsia.

    Science.gov (United States)

    Zahumensky, J

    2009-01-01

    The purpose of this study was to summarize the new published data on the Doppler flowmetry in preeclampsia. We summarize the new published data on the Doppler flowmetry in uteroplacental, fetoplacental and fetal circulation in preeclampsia. The present review summarized the results of clinical research on the Doppler flowmetry in the screening of risk of preclampsia, in the diagnosis of preclampsia and in the fetal risk in preclampsia (Ref. 19). Full Text (Free, PDF) www.bmj.sk.

  7. Steerable Doppler transducer probes

    International Nuclear Information System (INIS)

    Fidel, H.F.; Greenwood, D.L.

    1986-01-01

    An ultrasonic diagnostic probe is described which is capable of performing ultrasonic imaging and Doppler measurement consisting of: a hollow case having an acoustic window which passes ultrasonic energy and including chamber means for containing fluid located within the hollow case and adjacent to a portion of the acoustic window; imaging transducer means, located in the hollow case and outside the fluid chamber means, and oriented to direct ultrasonic energy through the acoustic window toward an area which is to be imaged; Doppler transducer means, located in the hollow case within the fluid chamber means, and movably oriented to direct Doppler signals through the acoustic window toward the imaged area; means located within the fluid chamber means and externally controlled for controllably moving the Doppler transducer means to select one of a plurality of axes in the imaged area along which the Doppler signals are to be directed; and means, located external to the fluid chamber means and responsive to the means for moving, for providing an indication signal for identifying the selected axis

  8. Pancreatic capillary blood flow during caerulein-induced pancreatitis evaluated by a laser-doppler flowmeter in rats Estudo das alterações do fluxo capilar pancreático após infusão de ceruleína avaliado por laser-Doppler em ratos

    Directory of Open Access Journals (Sweden)

    Roberto Ferreira Meirelles Jr.

    2003-01-01

    Full Text Available PURPOSE: The pancreatic capillary blood flow (PCBF was studied to determine its alterations during caerulein-induced pancreatitis in rats. METHODS: Twenty rats were divided in groups: control and caerulein. A laser-Doppler flowmeter to measure PCBF continuously was used. Blood pressure (BP and heart rate (HR were monitored. Serum biochemistry analyses were determined. Histopathological study was performed. RESULTS: The PCBF measured a mean of 109.08 ± 14.54% and 68.24 ± 10.47% in control group and caerulein group, respectively. Caerulein group had a mean decrease of 31.75 ± 16.79%. The serum amylase was 1323.70 ± 239.10U.I-1 and 2184.60 ± 700.46U.I-1 in control and caerulein groups, respectively. There was a significant difference in the PCBF (pOBJETIVO: O fluxo capilar pancreático (FCP foi estudado para determinar suas alterações durante a pancreatite aguda induzida por ceruleína, em ratos. MÉTODOS: Vinte ratos foram divididos em grupo controle e grupo ceruleína. Um laser-Doppler fluxímetro foi empregado para determinar, continuamente, o FCP durante 120 minutos. A pressão arterial média (PAM e a freqüência cardíaca (FC foram determinadas, durante o experimento. Análise bioquímica sérica e estudo histopatológico, por microscopia ótica, do tecido pancreático foram realizados, ao final do experimento. RESULTADOS: O FCP foi em média 109,08 ± 2,17% e 68,24 ± 16,79% nos grupos controle e ceruleína , respectivamente. No grupo ceruleína, houve uma diminuição média de 31,75 ± 16,79%. Os níveis de amilase sérica foram de 1323,70 ± 239,10U.I-1 e 2184,60 ± 700,46U.I-1 nos grupos controle e ceruleína, respectivamente. Houve diferença significante (p<0,05 no FCP e na amilasemia, quando comparado o grupo controle com o grupo ceruleína. Embora micro e macrovacuolização estivessem presentes no grupo ceruleína, não houve diferença histológica entre os grupos. CONCLUSÃO: A diminuição do FCP parece um evento precoce

  9. The Phase-Space Transformer Instrument (PASTIS) and the Phase-Space Transformation on Ultra-Cold Neutrons

    International Nuclear Information System (INIS)

    Henggeler, W.; Boehm, M.

    2003-11-01

    Both reports - part I by Wolfgang Henggeler and part II by Martin Boehm - serve as a comprehensive basis for the realisation of a PST (phase-space transformation) instrument coupled either to cold or ultra-cold neutrons, respectively. This publication accidentally coincides with the 200 th birthday of the Austrian physicist C.A. Doppler who discovered the principle (i.e., the effect denoted later by his name) giving rise to the phase-space transformation described in the present work. (author)

  10. Doppler radar flowmeter

    Science.gov (United States)

    Petlevich, Walter J.; Sverdrup, Edward F.

    1978-01-01

    A Doppler radar flowmeter comprises a transceiver which produces an audio frequency output related to the Doppler shift in frequency between radio waves backscattered from particulate matter carried in a fluid and the radiated radio waves. A variable gain amplifier and low pass filter are provided for amplifying and filtering the transceiver output. A frequency counter having a variable triggering level is also provided to determine the magnitude of the Doppler shift. A calibration method is disclosed wherein the amplifier gain and frequency counter trigger level are adjusted to achieve plateaus in the output of the frequency counter and thereby allow calibration without the necessity of being able to visually observe the flow.

  11. Analysis of Detectors and Transmission Curve Correction of Mobile Rayleigh Doppler Wind Lidar

    International Nuclear Information System (INIS)

    Tang Lei; Shu Zhi-Feng; Dong Ji-Hui; Wang Guo-Cheng; Xu Wen-Jing; Hu Dong-Dong; Wang Yong-Tao; Chen Ting-Di; Dou Xian-Kang; Sun Dong-Song; Cha Hyunki

    2010-01-01

    A mobile molecular Doppler wind lidar (DWL) based on double-edge technique is presented for wind measurement at altitudes from 10km to 40km. A triple Fabry-Perot etalon is employed as a frequency discriminator to determine the Doppler shift proportional to the wind velocity. The lidar operates at 355 nm with a 45-cm aperture telescope and a matching azimuth-over-elevation scanner that can provide full hemispherical pointing. In order to guarantee the wind accuracy, different forms of calibration function of detectors in different count rates response range would be especially valuable. The accuracy of wind velocity iteration is improved greatly because of application of the calibration function of linearity at the ultra low light intensity especially at altitudes from 10km to 40km. The calibration functions of nonlinearity make the transmission of edge channel 1 and edge channel 2 increase 38.9% and 27.7% at about 1 M count rates, respectively. The dynamic range of wind field measurement may also be extended because of consideration of the response function of detectors in their all possible operating range. (fundamental areas of phenomenology(including applications))

  12. The Huygens Doppler Wind Experiment: Ten Years Ago

    Science.gov (United States)

    Bird, Michael; Dutta-Roy, Robin; Dzierma, Yvonne; Atkinson, David; Allison, Michael; Asmar, Sami; Folkner, William; Preston, Robert; Plettemeier, Dirk; Tyler, Len; Edenhofer, Peter

    2015-04-01

    The Huygens Doppler Wind Experiment (DWE) achieved its primary scientific goal: the derivation of Titan's vertical wind profile from the start of Probe descent to the surface. The carrier frequency of the ultra-stable Huygens radio signal at 2040 MHz was recorded using special narrow-band receivers at two large radio telescopes on Earth: the Green Bank Telescope in West Virginia and the Parkes Radio Telescope in Australia. Huygens drifted predominantly eastward during the parachute descent, providing the first in situ confirmation of Titan's prograde super-rotational zonal winds. A region of surprisingly weak wind with associated strong vertical shear reversal was discovered within the range of altitudes from 65 to 100 km. Below this level, the zonal wind subsided monotonically from 35 m/s to about 7 km, at which point it reversed direction. The vertical profile of the near-surface winds implies the existence of a planetary boundary layer. Recent results on Titan atmospheric circulation within the context of the DWE will be reviewed.

  13. Fatores maternos associados ao peso fetal estimado pela ultra-sonografia

    OpenAIRE

    Melo,Adriana Suely de Oliveira; Amorim,Melania Maria Ramos de; Assunção,Paula Lisiane; Melo,Fabiana de Oliveira; Gondim,Sheila Sherezaide Rocha; Carvalho,Danielle Franklin de; Cardoso,Maria Aparecida Alves

    2008-01-01

    OBJETIVO: avaliar o efeito de variáveis maternas, socioeconômicas e obstétricas, assim como a presença de incisuras na 20ª e na 24ª semana, sobre o peso fetal estimado no final da gravidez (36ª semana) em gestantes atendidas pelo Programa Saúde da Família em uma cidade do interior do Nordeste do Brasil. MÉTODOS: estudo longitudinal incluindo 137 gestantes. As gestantes foram acompanhadas a cada quatro semanas para aferição das condições clínicas, socioeconômicas e obstétricas, incluindo o pes...

  14. Spatial weighting of Doppler reactivity feedback

    International Nuclear Information System (INIS)

    Carew, J.F.; Diamond, D.J.; Todosow, M.

    1977-12-01

    The spatial weighting of the local Doppler feedback implicit in the determination of the core Doppler feedback reactivity has been investigated. Using a detailed planar PDQ7-II PWR model with local fuel-temperature feedback, the core Doppler spatial weight factor, S, has been determined for various control patterns and power levels. Assuming power-squared weighting of the local Doppler feedback, a simple analytic expression for S has been derived and, based on comparison with the PDQ7-II results, provides a convenient and accurate representation of the Doppler spatial weight factor. The sensitivity of these results to variations in the fuel rod heat transfer coefficients, fuel loading and the magnitude of the Doppler coefficient has also been evaluated. The dependence of the local Doppler coefficient on moderator temperature, boron concentration and control rod density has been determined and found to be weak. Selected comparisons with vendor analyses have been made and indicate general agreement

  15. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...

  16. Doppler ultrasound monitoring technology.

    Science.gov (United States)

    Docker, M F

    1993-03-01

    Developments in the signal processing of Doppler ultrasound used for the detection of fetal heart rate (FHR) have improved the operation of cardiotocographs. These developments are reviewed and the advantages and disadvantages of the various Doppler and signal processing methods are compared.

  17. Differential doppler heterodyning technique

    DEFF Research Database (Denmark)

    Lading, Lars

    1971-01-01

    Measuring velocity without disturbing the moving object is possible by use of the laser doppler heterodyning technique. Theoretical considerations on the doppler shift show that the antenna property of the photodetector can solve an apparent conflict between two different ways of calculating...

  18. Estimativa da erodibilidade pela desagregação por ultra-som e atributos de solos com horizonte B textural Estimating soil erodibility from sonication indexes and other attributes of textural B horizon soils

    Directory of Open Access Journals (Sweden)

    Marcos Aurélio Carolino de Sá

    2004-07-01

    Full Text Available A erodibilidade de solos é um fator importante na estimativa das perdas por erosão. Este fator é uma expressão da combinação de atributos do solo, os quais possibilitam sua estimativa por meio de equações. O objetivo deste trabalho foi medir atributos químicos e mineralógicos que, combinados com índices de estabilidade de agregados determinados por ultra-som, pudessem ser utilizados como variáveis em modelos na estimativa da erodibilidade de solos com horizonte B textural do Brasil. Estes atributos foram determinados em 22 solos de erodibilidade conhecida, medida diretamente em parcelas no campo. Atributos de 21 dos solos foram utilizados no ajuste dos modelos. Um dos solos (Argissolo Vermelho-Amarelo foi escolhido ao acaso para teste. De 96 variáveis, 15 foram incluídas nos modelos de estimativa da erodibilidade. A maioria delas é representada por índices de desagregação por sonificação de amostras do horizonte A. Foram obtidos quatro modelos para estimar a erodibilidade, com R² variando entre 0,83** e 0,91**. A erodibilidade pode ser estimada com base na estabilidade de agregados por ultra-som.Soil erodibility is an important factor for estimating soil erosion losses. This factor is an expression of combined soil attributes, which make possible its estimation by equations. The objective of this study was to measure some chemical and mineralogical attributes, and to combine them with aggregate stability indexes from sonication analysis, in equations in order to estimate soil erodibility of textural B horizon soils from Brazil. These attributes were measured for 22 soils that had their erodibility measured from field plots. Attributes of 21 soils were used to adjust the equations. One of the soils (Red-Yellow Argisol was used to test the equations. From 96 variables, 15 were significantly correlated to soil erodibility. Most of them are represented by the disruption indexes from sonication analysis of A horizon samples. This

  19. Burst Format Design for Optimum Joint Estimation of Doppler-Shift and Doppler-Rate in Packet Satellite Communications

    Directory of Open Access Journals (Sweden)

    Luca Giugno

    2007-05-01

    Full Text Available This paper considers the problem of optimizing the burst format of packet transmission to perform enhanced-accuracy estimation of Doppler-shift and Doppler-rate of the carrier of the received signal, due to relative motion between the transmitter and the receiver. Two novel burst formats that minimize the Doppler-shift and the Doppler-rate Cramér-Rao bounds (CRBs for the joint estimation of carrier phase/Doppler-shift and of the Doppler-rate are derived, and a data-aided (DA estimation algorithm suitable for each optimal burst format is presented. Performance of the newly derived estimators is evaluated by analysis and by simulation, showing that such algorithms attain their relevant CRBs with very low complexity, so that they can be directly embedded into new-generation digital modems for satellite communications at low SNR.

  20. Patient-exposure data for doppler ultrasound

    International Nuclear Information System (INIS)

    Stewart, H.F.; Silvis, P.X.; Smith, S.W.

    1986-01-01

    In recent years ultrasound imaging and Doppler blood flow measurements have become important tools for use in diagnostic medicine. Commercial pulse-echo imaging equipment was first introduced into commerce in 1963. The first commercial continuous wave Doppler unit was introduced to the marketplace in 1966. As equipment improved and applications developed, the industry experienced rapid growth in the 1970s. One of the more recent growth areas in the application of diagnostic ultrasound has been the use of pulsed Doppler equipment for cardiac applications. Prior to 1976, some continuous wave Doppler ultrasound was used for cardiovascular diagnosis. However, only a single manufacturer marketed a pulsed Doppler clinical instrument for cardiac or peripheral vascular diagnosis. Currently, many continuous wave and pulsed Doppler instruments are commercially available for both peripheral vascular and cardiac diagnosis. This chapter (1) briefly reviews current safety guidelines, regulations, and recommendations for diagnostic ultrasound; (2) discusses the patient-exposure intensities associated with Doppler ultrasound medical equipment and compare these levels of exposure with intensities from other medical ultrasound devices; and (3) considers some of the current information as it relates to the safety of diagnostic ultrasound

  1. Doppler tomography in fusion plasmas and astrophysics

    DEFF Research Database (Denmark)

    Salewski, Mirko; Geiger, B.; Heidbrink, W. W.

    2015-01-01

    Doppler tomography is a well-known method in astrophysics to image the accretion flow, often in the shape of thin discs, in compact binary stars. As accretion discs rotate, all emitted line radiation is Doppler-shifted. In fast-ion Dα (FIDA) spectroscopy measurements in magnetically confined plasma......, the Dα-photons are likewise Doppler-shifted ultimately due to gyration of the fast ions. In either case, spectra of Doppler-shifted line emission are sensitive to the velocity distribution of the emitters. Astrophysical Doppler tomography has lead to images of accretion discs of binaries revealing bright...... and limits, analogies and differences in astrophysical and fusion plasma Doppler tomography and what can be learned by comparison of these applications....

  2. Doppler-guided retrograde catheterization system

    Science.gov (United States)

    Frazin, Leon J.; Vonesh, Michael J.; Chandran, Krishnan B.; Khasho, Fouad; Lanza, George M.; Talano, James V.; McPherson, David D.

    1991-05-01

    The purpose of this study was to investigate a Doppler guided catheterization system as an adjunctive or alternative methodology to overcome the disadvantages of left heart catheterization and angiography. These disadvantages include the biological effects of radiation and the toxic and volume effects of iodine contrast. Doppler retrograde guidance uses a 20 MHz circular pulsed Doppler crystal incorporated into the tip of a triple lumen multipurpose catheter and is advanced retrogradely using the directional flow information provided by the Doppler waveform. The velocity detection limits are either 1 m/second or 4 m/second depending upon the instrumentation. In a physiologic flow model of the human aortic arch, multiple data points revealed a positive wave form when flow was traveling toward the catheter tip indicating proper alignment for retrograde advancement. There was a negative wave form when flow was traveling away from the catheter tip if the catheter was in a branch or bent upon itself indicating improper catheter tip position for retrograde advancement. In a series of six dogs, the catheter was able to be accurately advanced from the femoral artery to the left ventricular chamber under Doppler signal guidance without the use of x-ray. The potential applications of a Doppler guided retrograde catheterization system include decreasing time requirements and allowing safer catheter guidance in patients with atherosclerotic vascular disease and suspected aortic dissection. The Doppler system may allow left ventricular pressure monitoring in the intensive care unit without the need for x-ray and it may allow left sided contrast echocardiography. With pulse velocity detection limits of 4 m/second, this system may allow catheter direction and passage into the aortic root and left ventricle in patients with aortic stenosis. A modification of the Doppler catheter may include transponder technology which would allow precise catheter tip localization once the

  3. Pulsed-wave tissue Doppler imaging of the myocardium of cats with induced thyrotoxicosis Doppler tecidual pulsado do miocárdio de gatos com tirotoxicose induzida

    Directory of Open Access Journals (Sweden)

    Daniel Capucho de Oliveira

    2011-06-01

    Full Text Available Left ventricular myocardial motion was quantified using pulsed-wave tissue Doppler imaging (PW-TDI in nine adult cats before and after thyrotoxicosis induction. In order to induce thyrotoxicosis, all cats were given 150µg kg-1 of levothyroxine sodium as a single oral dose each day for 10 weeks. PW-TDI examinations were performed immediately before the induction and by the end of the experimental protocol. An increase in myocardial motion velocity was documented at the interventricular septum level, demonstrated by an elevation in systolic (Sa, and early (Ea and late (Aa diastolic waves (PA velocidade de movimentação miocárdica do ventrículo esquerdo foi quantificada por meio de exames ecocardiográficos com Doppler tecidual pulsado (PW-TDI em nove gatos adultos antes e após indução à tirotoxicose. Para indução da tirotoxicose, todos os gatos receberam doses diárias de 150mg kg-1 de levotiroxina sódica, por via oral, durante 10 semanas. Os exames de PW-TDI foram realizados imediatamente antes da indução e ao final do protocolo experimental. Uma elevação na velocidade de movimentação miocárdica foi documentada ao nível do septo interventricular, demonstrado por um aumento das ondas sistólica (Sa e diastólicas (Ea e Aa; P<0,05. No entanto, nenhuma alteração nos valores de Sa, Ea e Aa foi encontrada ao nível da parede livre do ventrículo esquerdo. A frequência cardíaca aumentou significativamente entre os momentos experimentais, sendo que três animais apresentaram fusão das ondas Aa e Ea ao final do experimento. O protocolo experimental utilizado neste estudo causou alterações na velocidade de movimentação do miocárdio ventricular esquerdo, mas sem causar danos à função diastólica do ventrículo esquerdo.

  4. Aplicação da ultrassonografia colorida doppler em programas de transferência de embriões equinos Potential use of doppler ultrasound in equine embryo transfer programs

    Directory of Open Access Journals (Sweden)

    Jair Camargo Ferreira

    2011-06-01

    Full Text Available Os programas comerciais de transferência de embriões em éguas existem por mais de três décadas e são hoje uma das biotécnias mais utilizadas na reprodução assistida de equinos. O exame ultrassonográfico nos períodos pré e pós-cobertura de doadoras de embriões, assim como a avaliação de receptoras no momento da inovulação é de vital importância para o êxito de um programa de transferência de embriões. A ultrassonografia Doppler é uma técnica não-invasiva que permite a avaliação em tempo real da hemodinâmica do trato reprodutivo de animais de grande porte. Por fornecer detalhes anatômicos e informações imediatas sobre a fisiologia do fluxo sanguíneo de tecidos e órgãos, o exame doppler permite a avaliação do potencial ovulatório de folículos e do status funcional de corpo lúteo e útero, além de ser uma técnica auxiliar para o diagnóstico de distúrbios na hemodinâmica do sistema reprodutivo. Alterações na perfusão sanguínea dos futuros folículos dominantes são detectáveis em diferentes fases de seu desenvolvimento, como na divergência folicular e no período pré-ovulatório. A partir dessas informações, é possível determinar o princípio da atividade sexual e o momento ideal para o início de tratamentos superovulatórios e indutores de ovulação, assim como o momento mais apropriado para a realização de coberturas de éguas doadoras de embriões. A avaliação através do modo-Doppler do corpo lúteo e útero de éguas receptoras é também um instrumento auxiliar para a seleção de animais com perfil sérico de progesterona e ambiente uterino adequados para a sobrevivência do embrião e manutenção da gestação. Essa técnica pode ser útil ainda ao se avaliar a interação concepto-maternal. Apesar da aplicabilidade da tecnologia doppler dentro de programas de transferência de embriões, novos estudos visando a determinar padrões de normalidade e posterior caracterização de

  5. Avaliação crítica dos benefícios e limitações da ressonância magnética como método complementar no diagnóstico das malformações fetais A critical review of benefits and limitations of magnetic resonance imaging as a complementary method in the diagnosis of fetal malformations

    Directory of Open Access Journals (Sweden)

    Renato Luis da Silveira Ximenes

    2008-10-01

    Full Text Available OBJETIVO: Avaliar, por meio da ressonância magnética, uma série de fetos com diagnóstico ultra-sonográfico de malformação, a fim de estabelecer os benefícios e limites diagnósticos proporcionados pela técnica de ressonância magnética fetal, em comparação com a ultra-sonografia. MATERIAIS E MÉTODOS: Foram estudadas 40 mulheres entre 15-35 semanas de gestação com diagnóstico de anomalia fetal durante o exame de ultra-sonografia. As pacientes foram encaminhadas para o estudo complementar com ressonância magnética. As indicações para o estudo da ressonância magnética fetal foram: anomalias do sistema nervoso central, do tórax, do abdome, renais, esqueléticas e tumores. A avaliação pós-natal incluiu a revisão das imagens de ultra-sonografia e ressonância magnética, o acompanhamento do nascimento, exames laboratoriais, radiológicos e necropsia. RESULTADOS: Os resultados mostraram que os estudos complementares com ressonância magnética fetal trouxeram informações adicionais em 60% dos casos estudados. Os benefícios da ressonância magnética fetal foram: ampliação da avaliação global, aumento do campo de avaliação, maior resolução tecidual pelo uso de seqüências, e avaliação em pacientes obesas e com oligoidrâmnio. Os limites da ressonância magnética fetal foram: evitar exame no primeiro trimestre, avaliação do fluxo sanguíneo, movimentação fetal, claustrofobia materna, estudo do coração fetal e esqueleto. CONCLUSÃO: A ressonância magnética fetal pode ser utilizada como método complementar para a avaliação das malformações fetais.OBJECTIVE: The present study was aimed at evaluating by means of magnetic resonance imaging a series of fetuses with sonographic diagnosis of malformation, establishing the diagnostic benefits and limitations of fetal magnetic resonance imaging as compared with ultrasonography. MATERIALS AND METHODS: Forty women between 15-35 gestational weeks and previously

  6. Color doppler imaging of subclavian steal phenomenon

    International Nuclear Information System (INIS)

    Cho, Nari Ya; Chung, Tae Sub; Kim, Jai Keun

    1997-01-01

    To evaluate the characteristic color doppler imaging of vertebral artery flow in the subclavian steal phenomenon. The study group consisted of eight patients with reversed vertebral artery flow proved by color Doppler imaging. We classified this flow into two groups:(1) complete reversal;(2) partial reversal, as shown by Doppler velocity waveform. Vertebral angiography was performed in six of eight patients;color Doppler imaging and angiographic findings were compared. On color Doppler imaging, all eight cases with reversed vertebral artery flow showed no signal at the proximal subclavian or brachiocephalic artery. We confirmed shunting of six cases by performing angiography from the contralateral vertebral and basilar artery to the ipsilateral vertebral artery. On the Doppler spectrum, six cases showed complete reversal and two partial reversal. On angiography, one partial reversal case showed complete occlusion of the subclavian artery with abundant collateral circulation of muscular branches of the vertebral artery. On color Doppler imaging, a reversed vertebral artery suggests the subclavian steal phenomenon. In particular, partial reversal waveform may reflect collateral circulation

  7. Mobilidade do Colo Vesical e Avaliação Funcional do Assoalho Pélvico em Mulheres Continentes e com Incontinência Urinária de Esforço, Consoante o Estado Hormonal Bladder Neck Mobility and Functional Pelvic Floor Evaluation in Women with and without Stress Urinary Incontinence, According to Hormonal Status

    Directory of Open Access Journals (Sweden)

    Sonia Fátima da Silva Moreira

    2002-07-01

    Full Text Available Objetivo: estudar a mobilidade do colo vesical e a força da musculatura perineal em mulheres com e sem incontinência urinária de esforço, no menacme e na pós-menopausa. Métodos: foram avaliadas 61 pacientes, das quais 31 estavam no menacme, sendo 17 com incontinência urinária de esforço (IUE e 14 continentes, e 30 estavam na pós-menopausa, das quais 15 com e 15 sem IUE. Todas as incontinentes foram submetidas ao teste da coluna d'água e ao teste de esforço com bexiga vazia. A mobilidade do colo vesical foi avaliada pelo teste do cotonete e por ultra-sonografia e, para estudo da função da musculatura perineal, foram utilizados a palpação digital e cones vaginais. Resultados: a posição do colo vesical nas mulheres com incontinência urinária de esforço (grupos A e C, tanto pela ultra-sonografia quanto pelo teste do cotonete, foi mais baixa, sendo --11,8 cm no grupo A e --12,5 cm no grupo C, do que as mulheres continentes, nas quais o colo encontrava-se, em média, a +4,4 cm no grupo B e +2,3 cm no grupo D. Quanto à mobilidade do colo vesical, avaliada pela ultra-sonografia e pelo teste do cotonete, não houve diferença significativa entre os grupos continentes no menacme (9,1 cm e na pós-menopausa (9,5 cm. Também não houve diferença significativa entre os dois grupos incontinentes entre si (17,1 cm para o grupo A e 16,6 cm para o C. No entanto, a mobilidade foi significativamente maior nos grupos com incontinência urinária de esforço (A e C do que nos grupos continentes (B e D Verificamos que, quanto à avaliação da musculatura do assoalho pélvico, o teste realizado com cones vaginais e a avaliação funcional do assoalho pélvico mostraram índice 4 no grupo B e 3,4 no grupo D, indicando maior força muscular nas mulheres continentes, quando comparadas às incontinentes (2,9 e 2,3, respectivamente no menacme e na pós-menopausa. Conclusão: a mobilidade do colo vesical, avaliada por meio do teste do cotonete e da

  8. Radar micro-doppler signatures processing and applications

    CERN Document Server

    Chen, Victor C; Miceli, William J

    2014-01-01

    Radar Micro-Doppler Signatures: Processing and applications concentrates on the processing and application of radar micro-Doppler signatures in real world situations, providing readers with a good working knowledge on a variety of applications of radar micro-Doppler signatures.

  9. Invasão do nervo óptico por melanoma peripapilar: relato de caso Optic nerve invasion by juxtapapillary melanoma: case report

    Directory of Open Access Journals (Sweden)

    Eduardo Ferrari Marback

    2003-06-01

    Full Text Available Tumores pigmentados localizados sobre o disco óptico são raros e representam desafio diagnóstico. Paciente masculino, 60 anos, apresenta baixa da acuidade visual no olho esquerdo devido à lesão pigmentada que cobre o disco óptico. Foi indicada a enucleação com recusa pelo paciente. O quadro evoluiu com descolamento de retina. Examinado em outro serviço teve indicação de vitrectomia também recusada. Retorna aos nossos cuidados; feita a enucleação o diagnóstico anatomopatológico revelou melanoma maligno da coróide com invasão pós-laminar do nervo óptico. A importância prognóstica da invasão do nervo óptico por melanoma da coróide ainda não está totalmente esclarecida. Embora raro, tumor pigmentado cobrindo o nervo óptico pode representar melanoma maligno. O diagnóstico diferencial destes casos é geralmente difícil, porém seu reconhecimento à ultra-sonografia ocular é patente e descolamento de retina associado é sinal de atividade tumoral. Os riscos de disseminação da doença exigem atenção na suspeita diagnóstica e conduta precisa.Small-pigmented lesions over the optic disc are very rare and may represent a diagnostic challenge. To report a case of a small malignant choroidal melanoma invading the optic nerve. A 60-year-old male presents with low vision in the left eye due to a small, pigmented lesion over the optic disc. At first the patient refused enucleation. One month later, after further drop in visual acuity, the patient was seen at another service, diagnosed as having a retinal detachment, and pars plana vitrectomy was proposed but also refused by the patient. Returning to our service, the eye was enucleated and a final diagnosis of choroidal melanoma with post-laminar optic nerve invasion was made. Although rare, pigmented lesions over the optic disc may represent a malignant melanoma. The prognostic significance of optic nerve invasion by choroidal melanoma is not clear yet. The differential

  10. Color doppler sonography in thickened gallbladder wall

    International Nuclear Information System (INIS)

    Han, Sang Suk; Choi, Seok Jin; Seo, Chang Hae; Eun, Choong Ki

    1996-01-01

    The thickening of the gallbladder wall is a valuable finding for the diagnosis of cholecystitis, but may be seen in non-cholecystic disease as well as in acute or chronic cholecystitis. The purpose of this study is to determine the value of color Doppler sonography in differentiating the causes of thickened gallbladder wall. Ninety eight patients with thickened gallbladder wall(more than 3mm) which was not due to gallbladder cancer were prospectively evaluated with color Doppler sonography. Sixty-six cases, confirmed by pathologic reports and clinical records, were analyzed for correlation between thickened gallbladder wall and color flow signal according to the underlying causes. Of the 66 patients, 28 cases were cholecystitis and 38 cases had non-cholecystic causes such as liver cirrhosis, ascites, hepatitis, pancreatitis, renal failure, and hypoalbuminemia. Of the 28 patients with cholecystitis(12 acute, 16 chronic), 23(82%) had color Doppler flow signals in the thickened gallbladder wall. Of the 38 patients with non-cholecystic causes, eight(21%) had color Doppler flow signals. There was a statistically significant difference of color Doppler flow signals between the cholecystitis and non-cholecystic groups(p=0.0001). No significant difference of color Doppler flow signals was found between cases of acute and chronic cholecystitis. Of the 23 patients with color Doppler flow signals in 28 cases of cholecystitis, 18(78.3%) showed a linear pattern and five(21.7%) showed a spotty pattern. Of the eight patients with color Doppler flow signals in the 38 non-cholecystic cases, four(50%) showed a linear pattern and four(50%) showed a spotty pattern. In cholecystitis, a linear color Doppler flow signal pattern is a much more frequent finding than a spotty pattern. Color Doppler sonography is a useful and adequate method for determining whether a thickened gallbladder wall is the result of cholecystitis or has non-cholecystic causes

  11. Degeneração cística maciça de leiomioma uterino em gestante simulando neoplasia ovariana: relato de caso Degenerating cystic uterine fibroid mimics an ovarian cyst in a pregnant patient: a case report

    Directory of Open Access Journals (Sweden)

    Arildo Corrêa Teixeira

    2008-08-01

    Full Text Available Os autores descrevem o caso de uma gestante encaminhada por apresentar massa anexial. A ultra-sonografia demonstrou volumosa lesão sólido-cística sugestiva de neoplasia ovariana. A ressonância magnética mostrou que a lesão era recoberta pela serosa uterina, sugerindo mioma degenerado. O correto diagnóstico das massas pélvicas na gestação é fundamental para o estabelecimento da terapêutica. A ressonância magnética traz importantes contribuições no diagnóstico dessas entidades.The authors describe the case of a pregnant woman referred to the institution to be evaluated for an adnexal mass. Ultrasonography showed a voluminous solid-cystic lesion suggestive of ovarian neoplasm. Magnetic resonance imaging demonstrated that the lesion was located within the uterine serosa, suggesting the presence of a degenerated leiomyoma. A correct diagnosis of pelvic masses in pregnancy is essential for the definition of a therapeutic approach. Magnetic resonance imaging represents a relevant tool in the diagnosis of these abnormalities.

  12. Dano cavitacional em revestimentos depositados por aspersão termica a chama

    OpenAIRE

    Paulo Villani Marques

    1996-01-01

    Resumo: Quantias elevadas são gastas anualmente na manutenção de turbinas hidráulicas usadas na geração de energia elétrica por causa do ataque cavitacional. Avaliou-se a aplicabilidade de revestimentos metálicos e cerâmicos depositados sobre aço carbono por aspersão térmica a chama na manutenção destes equipamentos em função de sua resistência à erosão por cavitação. Foram realizados ensaios de dureza, rugosidade, ensaio acelerado de cavitação induzida por vibração ultra-sônica, adesão (traç...

  13. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  14. Imaging of foreign bodies in the face and ultrasound guided surgical removal; Diagnostico por imagem de corpos estranhos da face e retirada cirurgica guiada por ultra-sonografia

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Claudio Marcio Amaral de Oliveira; Gambin, Moises; Ribeiro, Erica Barreiros; Amarante Junior, Jose Luiz de Medeiros [Hospital Naval Marcilio Dias, Rio de Janeiro, RJ (Brazil)]. E-mail: cmaol@br.inter.net; cmaolima@hotmail.com; Monteiro, Alexandra Maria Vieira [Pontificia Univ. Catolica do Rio de Janeiro (PUC/Rio), RJ (Brazil). Curso de Pos-Graduacao em Radiologia

    2006-10-15

    The identification and surgical removal of foreign bodies is a complex procedure in medical practice, principally when the involved material is radiolucent. The technological advent of the ultrasonography equipment comes enlarging the field of application of this method more and more, in medical practice. The authors describe a case of an ultrasound guided surgical removal of glass fragments from the face of a patient. The foreign bodies were previously diagnosed by ultrasound and computed tomography. The guided technic showed secure, less invasive and efficient, allowing the retreat of all the fragments. (author)

  15. Importância da ecogenicidade da tireóide no diagnóstico da tireoidite crônica auto-imune Value of thyroid echogenicity in the diagnosis of chronic autoimmune thyroiditis

    Directory of Open Access Journals (Sweden)

    Danilo Bianchini Höfling

    2008-12-01

    Full Text Available A tireoidite crônica auto-imune é, atualmente, a principal causa de hipotireoidismo e seu diagnóstico baseia-se nas manifestações clínico-laboratoriais. O marcador laboratorial mais importante é a presença de anticorpos antitireoglobulina e antiperoxidase, sendo este último o teste mais sensível. A biópsia aspirativa apresenta alta sensibilidade e especificidade, porém, é um método invasivo e, por isso, reservado para quando há presença de nódulo ou bócio de crescimento rápido. A cintilografia é desnecessária para o diagnóstico, já que apresenta baixa sensibilidade e especificidade. A ultra-sonografia, tanto ao modo B como ao dúplex-Doppler colorido, evoluiu de forma muito rápida e tornou-se um método simples, não-invasivo, reprodutível e com alta sensibilidade para o diagnóstico da tireoidite crônica auto-imune. Ao modo B, a ecogenicidade é um parâmetro de extrema importância, já que, além de apresentar alta correlação com o quadro citopatológico, também apresenta alta sensibilidade para o diagnóstico da tireoidite crônica auto-imune. Embora este parâmetro não seja específico da tireoidite crônica auto-imune, pois também pode estar presente na doença de Graves, na tireoidite pós-parto e na tireoidite subaguda, tais desordens podem ser facilmente diferenciadas tanto pelo quadro clínico-laboratorial quanto pelo dúplex-Doppler colorido. Assim, este artigo tem o objetivo de revisar a importância do estudo da ecogenicidade no diagnóstico da tireoidite crônica auto-imune.Chronic autoimmune thyroiditis is currently considered as the main cause for hypothyroidism and its diagnosis is based on clinical manifestations and laboratory tests results. The most significant laboratory marker for this disease is the presence of anti-thyroperoxidase and anti-thyroglobulin antibodies, the latter being the most sensitive one. Aspiration biopsy shows high sensitivity and specificity but, considering the

  16. Measurement of soil aggregate stability using low intensity ultrasonic vibration Medición de la estabilidad de agregados de suelo utilizando vibración ultrasónica de baja intensidad Medição da estabilidade dos agregados do solo por vibração ultrasónica de baixa intensidade

    Directory of Open Access Journals (Sweden)

    Herwig Mayer

    2011-11-01

    del laboreo sobre la estabilidad de los agregados del suelo (soil aggregate stability – SAS utilizando un método de dispersión ultrasónica con diferentes niveles de energía. Se hicieron ensayos con un equipo de dispersión ultrasónica desarrollado en la Universidad de Ciencias de Recursos Naturales y de la Vida (Viena. Este equipo facilita la aplicación de amplitudes de baja vibración, de 0.5 µm, 2 µm y 5 µm. La potencia ultrasónica determinada por un método de balance de energía es de 0.7 W, 8.9 W y 22.3 W para cada amplitud. Se tomaron muestras de agregados de 2 000 a 250 µm, en tres tipos de suelo del este de Austria: un suelo del tipo Chernozem franco limoso degradado, un Cambisol franco arcilloso y un Cambisol franco arenoso, y sometidos a diferentes tipos de laboreo: laboreo convencional (CT – conventional tillage, laboreo con eliminación mecánica de malas hierbas y sin laboreo (NT – no tillage, con siembra intercalada en invierno. Los resultados de la estabilidad de los agregados del suelo obtenidos según la norma DIN (Deutsches Institut für Normung mostraron que la estabilidad disminuía en el siguiente orden: Cambisol franco arcilloso > Cambisol franco arenoso > Chernozem franco limoso. La influencia del tipo de laboreo se observó en el segundo y tercer tipo de los suelos mencionados. La dispersión ultrasónica por amplitudes de baja vibración mostró una estabilidad más alta en suelos del tipo Cambisol. Se observó una influencia significativa del tipo de laboreo sobre la estabilidad de los agregados del suelo (entre 1 y 1.7 J ml-1 en el Cambisol franco arcilloso y el Chernozem degradado, resultando una disminución de la estabilidad de los agregados en el orden siguiente: Cambisol NT > Cambisol CT > Chernozem NT > Chernozem CT. No se observaron diferencias en el Cambisol franco arenoso, porque el nivel de agregación de los macroagregados fue demasiado débil. Este trabajo destaca la importancia de cuantificar la energ

  17. The medical Doppler in hand surgery: its scientific basis, applications, and the history of its namesake, Christian Johann Doppler.

    Science.gov (United States)

    Ghori, Ahmer K; Chung, Kevin C

    2007-12-01

    The word Doppler is used synonymously in hand surgery for evaluating patency of vascular structures; however, the science and history behind the Doppler effect are not as well-known. We will present the theories behind the Doppler effect and the history of the person who made this discovery.

  18. Noncoherent Doppler tracking: first flight results

    Science.gov (United States)

    DeBoy, Christopher C.; Robert Jensen, J.; Asher, Mark S.

    2005-01-01

    Noncoherent Doppler tracking has been devised as a means to achieve highly accurate, two-way Doppler measurements with a simple, transceiver-based communications system. This technique has been flown as an experiment on the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) spacecraft, (launched 7 December 2001), as the operational technique for Doppler tracking on CONTOUR, and is baselined on several future deep space missions at JHU/APL. This paper reports on initial results from a series of successful tests of this technique between the TIMED spacecraft and NASA ground stations in the Deep Space Network. It also examines the advantages that noncoherent Doppler tracking and a transceiver-based system may offer to small satellite systems, including reduced cost, mass, and power.

  19. Anomalous Doppler effects in bulk phononic crystal

    International Nuclear Information System (INIS)

    Cai Feiyan; He Zhaojian; Zhang Anqi; Ding Yiqun; Liu Zhengyou

    2010-01-01

    Doppler effects in simple cubic phononic crystal are studied theoretically and numerically. In addition to observing Doppler shifts from a moving source's frequencies inside the gap, we find that Doppler shifts can be multi-order, anisotropic, and the dominant order of shift depends on the band index that the source's frequency is in.

  20. Quality Control of Wind Data from 50-MHz Doppler Radar Wind Profiler

    Science.gov (United States)

    Vacek, Austin

    2016-01-01

    Upper-level wind profiles obtained from a 50-MHz Doppler Radar Wind Profiler (DRWP) instrument at Kennedy Space Center are incorporated in space launch vehicle design and day-of-launch operations to assess wind effects on the vehicle during ascent. Automated and manual quality control (QC) techniques are implemented to remove spurious data in the upper-level wind profiles caused from atmospheric and non-atmospheric artifacts over the 2010-2012 period of record (POR). By adding the new quality controlled profiles with older profiles from 1997-2009, a robust database will be constructed of upper-level wind characteristics. Statistical analysis will determine the maximum, minimum, and 95th percentile of the wind components from the DRWP profiles over recent POR and compare against the older database. Additionally, this study identifies specific QC flags triggered during the QC process to understand how much data is retained and removed from the profiles.

  1. Estimating the Doppler centroid of SAR data

    DEFF Research Database (Denmark)

    Madsen, Søren Nørvang

    1989-01-01

    attractive properties. An evaluation based on an existing SEASAT processor is reported. The time-domain algorithms are shown to be extremely efficient with respect to requirements on calculations and memory, and hence they are well suited to real-time systems where the Doppler estimation is based on raw SAR......After reviewing frequency-domain techniques for estimating the Doppler centroid of synthetic-aperture radar (SAR) data, the author describes a time-domain method and highlights its advantages. In particular, a nonlinear time-domain algorithm called the sign-Doppler estimator (SDE) is shown to have...... data. For offline processors where the Doppler estimation is performed on processed data, which removes the problem of partial coverage of bright targets, the ΔE estimator and the CDE (correlation Doppler estimator) algorithm give similar performance. However, for nonhomogeneous scenes it is found...

  2. Power and color Doppler ultrasound settings for inflammatory flow

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin

    2015-01-01

    OBJECTIVE: To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. METHODS: Six different types of ultrasound machines were used....... On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA......) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity. RESULTS...

  3. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The TCSP ER-2 DOPPLER RADAR (EDOP) dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of the ER-2...

  4. CAMEX-4 ER-2 DOPPLER RADAR V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The CAMEX-4 ER-2 Doppler Radar dataset was collected by the ER-2 Doppler radar (EDOP), which is an X-band (9.6 GHz) Doppler radar mounted in the nose of ER-2. The...

  5. Direct Doppler auscultation of the carotid arteries

    International Nuclear Information System (INIS)

    Nix, L.

    1984-01-01

    The results of the carotid Doppler examinations and contrast arteriograms are presented. The overall sensitivity of the carotid Doppler examinations in detecting severe stenosis or occlusion of the carotid artery was 92%. The Doppler studies correctly differentiated these two conditions in 84% of the diseased vessels. In carotid arteries with stenosis greater than or equal to 50%, the sensitivity of the Doppler examinations was 90%, and these studies suggested stenosis in all but two of the 36 abnormal examinations. In two patent carotids with greater than 90% stenosis, a signal could not be elicited, presumably because of the low blood flow through the severely stenotic segment

  6. Recommendations for terminology and display for doppler echocardiography

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Doppler echocardiography has recently emerged as a major noninvasive technique with many applications in cardiology. To a large extent, this has been based upon a combination of clinical and engineering advances which now make possible the use of quantitative Doppler echocardiography in combination with two-dimensional imaging for measurement of volume flows, transvalve gradients, and other physiologic flow parameters which reflect cardiac function. It was the purpose of this Committee to provide a glossary of terms which could be used in standard fashion for papers and discussions related to Doppler echocardiography. As part of its task, the Committee also undertook an attempt to recommend a standard for display of Doppler information which would be useful, both for manufacturers and for clinicians. The document, therefore, includes: Section I, the Committee's recommendations for Doppler display. Section II, the glossary of Doppler terms, related to engineering and to clinical applications

  7. Plans for an Ultra Cold Neutron source at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Seestrom, S.J.; Bowles, T.J.; Hill, R.; Greene, G.L. [Los Alamos National Lab., NM (United States)

    1996-08-01

    Ultra Cold Neutrons (UCN) can be produced at spallation sources using a variety of techniques. To date the technique used has been to Bragg scatter and Doppler shift cold neutrons into UCN from a moving crystal. This is particularly applicable to short-pulse spallation sources. We are presently constructing a UCN source at LANSCE using method. In addition, large gains in UCN density should be possible using cryogenic UCN sources. Research is under way at Gatchina to demonstrate technical feasibility of be a frozen deuterium source. If successful, a source of this type could be implemented at future spallation source, such as the long pulse source being planned at Los Alamos, with a UCN density that may be two orders of magnitude higher than that presently available at reactors. (author)

  8. High-Frame-Rate Power Doppler Ultrasound Is More Sensitive than Conventional Power Doppler in Detecting Rheumatic Vascularisation

    NARCIS (Netherlands)

    M. van der Ven (Myrthe); J.J. Luime (Jolanda); van der Velden, L.L. (Levinia L.); J.G. Bosch (Hans); J.M.W. Hazes (Mieke); H.J. Vos (Rik)

    2016-01-01

    textabstractEarly recognition of joint inflammation will increase treatment efficacy in rheumatoid arthritis (RA). Yet, conventional power Doppler (PD) ultrasound might not be sufficiently sensitive to detect minor inflammation. We investigated the sensitivity of high-frame rate Doppler, combined

  9. Power doppler 'blanching' after the application of transducer pressure

    International Nuclear Information System (INIS)

    Joshua, F.; Edmonds, J.; Lassere, M.; De Carle, R.; Rayment, M.; Bryant, C.; Shnier, R.

    2005-01-01

    The aim of this study was to determine if transducer pressure modifies power Doppler assessments of rheumatoid arthritis synovium at the metacarpophalangeal joints and metatarsophalangeal joints. Five rheumatoid arthritis patients of varying degrees of 'disease activity' and damage were assessed with power Doppler ultrasound scanning of the dominant hand second to fifth metacarpophalangeal joints. Two rheumatoid arthritis patients had their dominant foot first to fifth metatarsophalangeal joints assessed with power Doppler ultrasound. Ultrasonography was performed with a high frequency transducer (14 MHz) with a colour mode frequency of 10 Mhz, and a standard colour box and gain. In the joint that showed the highest power Doppler signal, an image was made. A further image was taken after transducer pressure was applied. In all patients, there was increased flow to at least one joint. After pressure was applied, power Doppler signal intensity markedly reduced in all images and in some there was no recordable power Doppler signal. Increased transducer pressure can result in a marked reduction or obliteration in power Doppler signal. This power Doppler 'blanching' shows the need for further studies to evaluate sources of error and standardization before power Doppler ultrasound becomes a routine measure of 'disease activity' in rheumatoid arthritis. Copyright (2005) Blackwell Science Pty Ltd

  10. Development of the doppler electron velocimeter: theory.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.

    2007-03-01

    Measurement of dynamic events at the nano-scale is currently impossible. This paper presents the theoretical underpinnings of a method for making these measurements using electron microscopes. Building on the work of Moellenstedt and Lichte who demonstrated Doppler shifting of an electron beam with a moving electron mirror, further work is proposed to perfect and utilize this concept in dynamic measurements. Specifically, using the concept of ''fringe-counting'' with the current principles of transmission electron holography, an extension of these methods to dynamic measurements is proposed. A presentation of the theory of Doppler electron wave shifting is given, starting from the development of the de Broglie wave, up through the equations describing interference effects and Doppler shifting in electron waves. A mathematical demonstration that Doppler shifting is identical to the conceptually easier to understand idea of counting moving fringes is given by analogy to optical interferometry. Finally, potential developmental experiments and uses of a Doppler electron microscope are discussed.

  11. ULTRA-LIGHTWEIGHT CEMENT

    International Nuclear Information System (INIS)

    Fred Sabins

    2001-01-01

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Issues, Task 2: Review Russian Ultra-Lightweight Cement Literature, Task 3: Test Ultra-Lightweight Cements, and Task 8: Develop Field ULHS Cement Blending and Mixing Techniques. Results reported this quarter include: preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; summary of pertinent information from Russian ultra-lightweight cement literature review; laboratory tests comparing ULHS slurries to foamed slurries and sodium silicate slurries for two different applications; and initial laboratory studies with ULHS in preparation for a field job

  12. Re-Normalization Method of Doppler Lidar Signal for Error Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Nakgyu; Baik, Sunghoon; Park, Seungkyu; Kim, Donglyul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Dukhyeon [Hanbat National Univ., Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, we presented a re-normalization method for the fluctuations of Doppler signals from the various noises mainly due to the frequency locking error for a Doppler lidar system. For the Doppler lidar system, we used an injection-seeded pulsed Nd:YAG laser as the transmitter and an iodine filter as the Doppler frequency discriminator. For the Doppler frequency shift measurement, the transmission ratio using the injection-seeded laser is locked to stabilize the frequency. If the frequency locking system is not perfect, the Doppler signal has some error due to the frequency locking error. The re-normalization process of the Doppler signals was performed to reduce this error using an additional laser beam to an Iodine cell. We confirmed that the renormalized Doppler signal shows the stable experimental data much more than that of the averaged Doppler signal using our calibration method, the reduced standard deviation was 4.838 Χ 10{sup -3}.

  13. Maximisation of the Doppler effect in thermal reactors

    International Nuclear Information System (INIS)

    Bende, E.E.

    1998-03-01

    Increase of the fuel temperature in a nuclear reactor leads, or can lead, to (1) A Doppler broadening of the resonances of the nuclides in the fuel; (2) An expansion of the fuel; and (3) A shift of the Maxwellian part of the spectrum to higher energies. These processes together introduce a certain amount of reactivity, which can be expressed in the so-called fuel temperature reactivity coefficient. The reactivity effect of the third process is very small, because the Maxwell spectrum is to a major extent determined by the moderator temperature. Moreover, the reactivity effect due to an expansion of the fuel is small too, for most thermal systems. When the second and third processes can be neglected, the fuel temperature reactivity effect is fully determined by the Doppler effect. The fuel temperature reactivity coefficient is then called the Doppler coefficient of reactivity. The Doppler broadening of the resonances causes an increase of resonance absorption, due to a decrease of self-shielding. The competition between resonance fission at the one hand and resonance capture at the other hand determines the sign and magnitude of the reactivity induced by an increase of the fuel temperature. In well-designed nuclear reactors the Doppler effect due to resonance capture by fertile nuclides exceeds the Doppler effect due to resonance fission, which implies that an increase of the fuel temperature causes a negative reactivity effect and a correspondingly negative Doppler coefficient. Since the Doppler effect is a prompt effect, occurring simultaneously with the dissipation of kinetic energy of the fission products into temperature, it is very important in the study of rapid power transients. In this report, the Doppler coefficient of reactivity is defined in chapter 2. Chapter 3 discusses the geometry of the unit-cell for which the calculations are performed and describes the fuel types that have been investigated. In chapter 4 the 'Doppler efficiency' is introduced and

  14. Is Doppler ultrasound useful for evaluating gestational trophoblastic disease?

    Directory of Open Access Journals (Sweden)

    Lawrence H. Lin

    Full Text Available Doppler ultrasound is a non-invasive method for evaluating vascularization and is widely used in clinical practice. Gestational trophoblastic neoplasia includes a group of highly vascularized malignancies derived from placental cells. This review summarizes data found in the literature regarding the applications of Doppler ultrasound in managing patients with gestational trophoblastic neoplasia. The PubMed/Medline, Web of Science, Cochrane and LILACS databases were searched for articles published in English until 2014 using the following keywords: “Gestational trophoblastic disease AND Ultrasonography, Doppler.” Twenty-eight articles met the inclusion criteria and were separated into the 4 following groups according to the aim of the study. (1 Doppler ultrasound does not seem to be capable of differentiating partial from complete moles, but it might be useful when evaluating pregnancies in which a complete mole coexists with a normal fetus. (2 There is controversy in the role of uterine artery Doppler velocimetry in the prediction of development of gestational trophoblastic neoplasia. (3 Doppler ultrasound is a useful tool in the diagnosis of gestational trophoblastic neoplasia because abnormal myometrial vascularization and lower uterine artery Doppler indices seem to be correlated with invasive disease. (4 Lower uterine artery Doppler indices in the diagnosis of gestational trophoblastic neoplasia are associated with methotrexate resistance and might play a role in prognosis. CONCLUSION: Several studies support the importance of Doppler ultrasound in the management of patients with gestational trophoblastic neoplasia, particularly the role of Doppler velocimetry in the prediction of trophoblastic neoplasia and the chemoresistance of trophoblastic tumors. Doppler findings should be used as ancillary tools, along with human chorionic gonadotropin assessment, in the diagnosis of gestational trophoblastic neoplasia.

  15. Is Doppler ultrasound useful for evaluating gestational trophoblastic disease?

    Science.gov (United States)

    Lin, Lawrence H; Bernardes, Lisandra S; Hase, Eliane A; Fushida, Koji; Francisco, Rossana P V

    2015-12-01

    Doppler ultrasound is a non-invasive method for evaluating vascularization and is widely used in clinical practice. Gestational trophoblastic neoplasia includes a group of highly vascularized malignancies derived from placental cells. This review summarizes data found in the literature regarding the applications of Doppler ultrasound in managing patients with gestational trophoblastic neoplasia. The PubMed/Medline, Web of Science, Cochrane and LILACS databases were searched for articles published in English until 2014 using the following keywords: "Gestational trophoblastic disease AND Ultrasonography, Doppler." Twenty-eight articles met the inclusion criteria and were separated into the 4 following groups according to the aim of the study. (1) Doppler ultrasound does not seem to be capable of differentiating partial from complete moles, but it might be useful when evaluating pregnancies in which a complete mole coexists with a normal fetus. (2) There is controversy in the role of uterine artery Doppler velocimetry in the prediction of development of gestational trophoblastic neoplasia. (3) Doppler ultrasound is a useful tool in the diagnosis of gestational trophoblastic neoplasia because abnormal myometrial vascularization and lower uterine artery Doppler indices seem to be correlated with invasive disease. (4) Lower uterine artery Doppler indices in the diagnosis of gestational trophoblastic neoplasia are associated with methotrexate resistance and might play a role in prognosis. Several studies support the importance of Doppler ultrasound in the management of patients with gestational trophoblastic neoplasia, particularly the role of Doppler velocimetry in the prediction of trophoblastic neoplasia and the chemoresistance of trophoblastic tumors. Doppler findings should be used as ancillary tools, along with human chorionic gonadotropin assessment, in the diagnosis of gestational trophoblastic neoplasia.

  16. Preliminary simulation study of doppler reflectometry

    International Nuclear Information System (INIS)

    Ishii, Yuta; Hojo, Hitoshi; Yoshikawa, Masashi; Ichimura, Makoto; Haraguchi, Yusuke; Imai, Tsuyoshi; Mase, Atsushi

    2010-01-01

    A preliminary simulation study of Doppler reflectometry is performed. The simulations solve Maxwell's equations by a finite difference time domain (FDTD) code method in two dimensions. A moving corrugated metal target is used as a plasma cutoff layer to study the basic features of Doppler reflectometry. We examined the effects of the full width at half maximum (FWHM) of the electromagnetic waves and the corrugation depth of the metal target. Furthermore, the effect of a nonuniform plasma is studied using this FDTD analysis. The Doppler shift and velocity are compared with those obtained from FDTD analysis of a uniform plasma. (author)

  17. Doppler speedometer for micro-organisms

    International Nuclear Information System (INIS)

    Penkov, F.; Tuleushev, A.; Lisitsyn, V.; Kim, S.; Tuleushev, Yu.

    1996-01-01

    Objective of Investigations: Development and creation of the Doppler speedometer for micro-organisms which allows to evaluate, in a real temporal scale, variations in the state of water suspension of micro-organisms under the effect of chemical, physical and other external actions. Statement of the Problem The main problem is absence of reliable, accessible for users and simple, in view of application, Doppler speedometers for micro-organisms. Nevertheless, correlation Doppler spectrometry in the regime of heterodyning the supporting and cell-scattered laser radiation is welt known. The main idea is that the correlation function of photo-current pulses bears an information on the averages over the assembly of cell velocities. For solving the biological problems, construction of auto-correlation function in the real-time regime with the delay time values comprising, function in the real-time regime with the delay time values comprising, nearly, 100 me (10 khz) or higher is needed. Computers of high class manage this problem using but the program software. Due to this, one can simplify applications of the proposed techniques provided he creates the Doppler speedometer for micro-organism on a base of the P entium . Expected Result Manufactured operable mock-up of the Doppler speedometer for micro-organisms in a form of the auxiliary computer block which allows to receive an information, in the real time scale, on the results of external effects of various nature on the cell assembly in transparent medium with a small volume of the studied cell suspension

  18. De-Dopplerization of Acoustic Measurements

    Science.gov (United States)

    2017-08-10

    accurate measurement of aircraft location to resample the time signal to account for the compression and expansion of acoustic wavefronts. Correcting...AFRL-RH-WP-TR-2017-0043 DE-DOPPLERIZATION OF ACOUSTIC MEASUREMENTS Frank Mobley, PhD 711 HPW/RHCB Wright-Patterson AFB OH...TITLE AND SUBTITLE DE-DOPPLERIZATION OF ACOUSTIC MEASUREMENTS 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER

  19. Calculation of the Doppler broadening function using Fourier analysis;Calculo da funcao de alargamento Doppler utilizando analise de Fourier

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Alessandro da Cruz

    2010-07-01

    An efficient and precise method for calculation of Doppler broadening function is very important to obtain average group microscopic cross sections, self shielding factors, resonance integrals and others reactor physics parameter. In this thesis two different methods for calculation of Doppler broadening function and interference term will be presented. The main method is based on a new integral form for Doppler broadening function {psi}(x,{zeta}) which gives a mathematical interpretation of the approximation proposed by Bethe and Placzek, as the convolution of the Lorentzian function with a Gaussian function. This interpretation besides leading to a new integral form for {psi}(x,{zeta}), enables to obtain a simple analytic solution for the Doppler broadening function. (author)

  20. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  1. The phenomenon of Doppler

    International Nuclear Information System (INIS)

    Stoll, I.; Seidlerova, I.; Schwippel, J.; Poss, O.; Solc, M.

    1992-01-01

    The book is devoted to the life and work of Christian Doppler and particularly to his links to Prague and to the Slovak town of Banska Stiavnica. Many historical facts concerning Doppler's activities as well as the history of physics and astronomy are collected. Information is also presented about the Czech Technical University, the Society of Czechoslovak Mathematicians and Physicists, the Czechoslovak Astronomical Society, the Czechoslovak Spectroscopic Society and the Czechoslovak Society for the History of Science and Technology. The publication is amply supplemented with historical pictorial material (M.D.). 92 figs., 82 refs

  2. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Maulik, D.

    2005-01-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  3. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Maulik, D. [Winthrop Univ. Hospital, Mineola, NY (United States). Dept. of Obstetrics and Gynecology; Zalud, I. (eds.) [Kapiolani Medical Center for Women and Children, Honolulu, HI (United States)

    2005-07-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  4. New Insights from Inside-Out Doppler Tomography

    Directory of Open Access Journals (Sweden)

    E. J. Kotze

    2015-02-01

    Full Text Available We present preliminary results from our investigation into using an “inside-out” velocity space for creating a Doppler tomogram. The aim is to transpose the inverted appearance of the Cartesian velocity space used in normal Doppler tomography. In a comparison between normal and inside-out Doppler tomograms of cataclysmic variables, we show that the inside-out velocity space has the potential to produce new insights into the accretion dynamics in these systems.

  5. Measurement of ventricular function using Doppler ultrasound

    International Nuclear Information System (INIS)

    Teague, S.M.

    1986-01-01

    Doppler has wide application in the evaluation of valvular heart disease. The need to know ventricular function is a much more common reason for an echocardiographic evaluation. Interestingly, Doppler examinations can assess ventricular function from many perspectives. Description of ventricular function entails measurement of the timing, rate and volume of ventricular filling and ejection. Doppler ultrasound examination reveals all of these aspects of ventricular function noninvasively, simply, and without great expense or radiation exposure, as described in this chapter

  6. Fertilização in vitro com ciclos programados de baixo custo - avaliação de resultados iniciais de um centro de reprodução humana de hospital de ensino In vitro fertilization with low-cost programmed cycles - first outcome in a teaching hospital

    Directory of Open Access Journals (Sweden)

    Nelson Antunes Júnior

    2003-01-01

    Full Text Available OBJETIVOS: avaliação dos resultados iniciais de fertilização in vitro (FIV em instituição universitária, empregando ciclos programados de baixo custo. MÉTODOS: entre maio e dezembro de 2002, foram iniciados 66 ciclos programados de FIV, utilizando acetato de noretisterona, citrato de clomifeno e gonadotrofina coriônica humana (hCG. A punção folicular guiada por ultra-sonografia foi realizada 34 a 36 horas após a administração de hCG e a transferência, 48 horas após a punção. A gestação foi considerada clínica após visualização de batimentos cardíacos à ultra-sonografia transvaginal. RESULTADOS: a taxa de cancelamento foi de 21,2%. Em média, 2,8 folículos e 1,7 oócitos foram obtidos por punção. Em 79,6% dos ciclos puncionados recuperaram-se oócitos, que foram fertilizados em 69% dos casos. O número de embriões por transferência foi de 1,5. Houve algum grau de dificuldade em 10,2% das punções e 32,4% das transferências realizadas. A taxa de gestação obtida foi de 10,8% por transferência, entretanto, o custo com medicação por embrião transferido foi de apenas R$ 96,00. CONCLUSÃO: evidenciam-se as dificuldades de iniciar um programa de FIV em instituição de ensino, sem fins lucrativos e voltada à população carente. Com a prática, a taxa cumulativa de gravidez tende a ser semelhante às dos centros de referência, porém com custo e incidência de complicações significativamente inferiores.PURPOSE: to evaluate the first in vitro fertilization results at a medical university using low-cost programmed cycles. METHODS: from May to December 2002, 66 programmed cycles of in vitro fertilization were carried out using norethisterone acetate, clomiphene citrate and human chorionic gonadotrophin (hCG. The ovarian follicle aspiration was guided by ultrasonography, 34 to 36 h after the administration of hCG, and the embryo transfer, 48 h after puncturing. The diagnosis of clinical pregnancy was defined when a

  7. MP3 compression of Doppler ultrasound signals.

    Science.gov (United States)

    Poepping, Tamie L; Gill, Jeremy; Fenster, Aaron; Holdsworth, David W

    2003-01-01

    The effect of lossy, MP3 compression on spectral parameters derived from Doppler ultrasound (US) signals was investigated. Compression was tested on signals acquired from two sources: 1. phase quadrature and 2. stereo audio directional output. A total of 11, 10-s acquisitions of Doppler US signal were collected from each source at three sites in a flow phantom. Doppler signals were digitized at 44.1 kHz and compressed using four grades of MP3 compression (in kilobits per second, kbps; compression ratios in brackets): 1400 kbps (uncompressed), 128 kbps (11:1), 64 kbps (22:1) and 32 kbps (44:1). Doppler spectra were characterized by peak velocity, mean velocity, spectral width, integrated power and ratio of spectral power between negative and positive velocities. The results suggest that MP3 compression on digital Doppler US signals is feasible at 128 kbps, with a resulting 11:1 compression ratio, without compromising clinically relevant information. Higher compression ratios led to significant differences for both signal sources when compared with the uncompressed signals. Copyright 2003 World Federation for Ultrasound in Medicine & Biology

  8. Do ultra-orphan medicinal products warrant ultra-high prices? A review

    Directory of Open Access Journals (Sweden)

    Picavet E

    2013-06-01

    Full Text Available Eline Picavet,1 David Cassiman,2 Steven Simoens1 1Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium; 2Department of Hepatology, University Hospital Leuven, Leuven, Belgium Abstract: Ultra-orphan medicinal products (ultra-OMPs are intended for the treatment, prevention, or diagnosis of ultra-rare diseases, ie, life-threatening or chronically debilitating diseases that affect less than one per 50,000 individuals. Recently, high prices for ultra-OMPs have given rise to debate on the sustainability and justification of these prices. The aim of this article is to review the international scientific literature on the pricing of ultra-OMPs and to provide an overview of the current knowledge on the drivers of ultra-OMP pricing. The pricing process of ultra-OMPs is a complex and nontransparent issue. Evidence in the literature seems to indicate that ultra-OMPs are priced according to rarity and what the manufacturer believes the market will bear. Additionally, there appears to be a trend between the price of an ultra-OMP and the number of available alternatives. Patients, third-party payers, and pharmaceutical companies could benefit from more transparent pricing strategies. With a view to containing health care costs, it is likely that cost-sharing strategies, such as performance-based risk sharing arrangements, will become increasingly more important. However, it is vital that any measures for price control are consistent with the intended goals of the incentives to promote the development of new OMPs. Ideally, a balance must be struck between attaining affordable prices for ultra-OMPs and securing a realistic return on investment for the pharmaceutical industry. Keywords: ultra-orphan medicinal product, ultra-rare disease, pricing

  9. Analysis of Doppler effect with JAERI-Fast set

    International Nuclear Information System (INIS)

    Takano, Hideki; Matsui, Yasushi.

    1977-07-01

    Temperature dependence of group cross sections in the JAERI-Fast set versions I, IR, II and IIR has been tested from the analysis of Doppler experiments performed with two different methods. One is Doppler reactivity measurement for the whole core of SEFOR assembly, and the other sample Doppler reactivity measurement for natural UO 2 in FCA assemblies V-1, V-2, VI-1 and VI-2, ZPR-6-7, ZPR-3-47, and ZPPR-2 and 3. Doppler effects were calculated with one- and two-dimensional diffusion 1-st order perturbation code DOPP2D. The results calculated with the JAERI-Fast set versions II and IIR are in good agreement with the experimental ones. In these calculation, resonance heterogeneity effect, stainless-stell buffer effect and plate heterogeneity effect are considered, and these effects contribute significantly to Doppler effect. (auth.)

  10. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  11. Complex regression Doppler optical coherence tomography

    Science.gov (United States)

    Elahi, Sahar; Gu, Shi; Thrane, Lars; Rollins, Andrew M.; Jenkins, Michael W.

    2018-04-01

    We introduce a new method to measure Doppler shifts more accurately and extend the dynamic range of Doppler optical coherence tomography (OCT). The two-point estimate of the conventional Doppler method is replaced with a regression that is applied to high-density B-scans in polar coordinates. We built a high-speed OCT system using a 1.68-MHz Fourier domain mode locked laser to acquire high-density B-scans (16,000 A-lines) at high enough frame rates (˜100 fps) to accurately capture the dynamics of the beating embryonic heart. Flow phantom experiments confirm that the complex regression lowers the minimum detectable velocity from 12.25 mm / s to 374 μm / s, whereas the maximum velocity of 400 mm / s is measured without phase wrapping. Complex regression Doppler OCT also demonstrates higher accuracy and precision compared with the conventional method, particularly when signal-to-noise ratio is low. The extended dynamic range allows monitoring of blood flow over several stages of development in embryos without adjusting the imaging parameters. In addition, applying complex averaging recovers hidden features in structural images.

  12. Cross-correlation Doppler global velocimetry (CC-DGV)

    Science.gov (United States)

    Cadel, Daniel R.; Lowe, K. Todd

    2015-08-01

    A flow velocimetry method, cross-correlation Doppler global velocimetry (CC-DGV), is presented as a robust, simplified, and high dynamic range implementation of the Doppler global/planar Doppler velocimetry technique. A sweep of several gigahertz of the vapor absorption spectrum is used for each velocity sample, with signals acquired from both Doppler-shifted scattered light within the flow and a non-Doppler shifted reference beam. Cross-correlation of these signals yields the Doppler shift between them, averaged over the duration of the scan. With presently available equipment, velocities from 0 ms-1 to over 3000 ms-1 can notionally be measured simultaneously, making the technique ideal for high speed flows. The processing routine is shown to be robust against large changes in the vapor pressure of the iodine cell, benefiting performance of the system in facilities where ambient conditions cannot be easily regulated. Validation of the system was performed with measurements of a model wind turbine blade boundary layer made in a 1.83 m by 1.83 m subsonic wind tunnel for which laser Doppler velocimetry (LDV) measurements were acquired alongside the CC-DGV results. CC-DGV uncertainties of ±1.30 ms-1, ±0.64 ms-1, and ±1.11 ms-1 were determined for the orthogonal stream-wise, transverse-horizontal, and transverse-vertical velocity components, and root-mean-square deviations of 2.77 ms-1 and 1.34 ms-1 from the LDV validation results were observed for Reynolds numbers of 1.5 million and 2 million, respectively. Volumetric mean velocity measurements are also presented for a supersonic jet, with velocity uncertainties of ±4.48 ms-1, ±16.93 ms-1, and ±0.50 ms-1 for the orthogonal components, and self-validation done by collapsing the data with a physical scaling.

  13. Editorial special issue on "Laser Doppler vibrometry"

    Science.gov (United States)

    Vanlanduit, Steve; Dirckx, Joris

    2017-12-01

    The invention of the laser in 1960 has opened up many opportunities in the field of measurement science and technology. Just a few years after the invention of the laser, a novel fluid flow measurement technique based on the Doppler effect was introduced: at that moment the laser Doppler anemometer or shortly LDA [1] was born. The technique enabled fluid velocity measurement by using the light of a He-Ne beam which was scattered by very small polystyrene spheres entrained in the fluid. Later on, in the late nineteen seventees it was recognized that the detection of the Doppler frequency shift that occurs when light is scattered by a moving surface can also be used to measure the vibration velocity of an object. The instrument to perform these vibration measurements was called the laser Doppler vibrometer or LDV [2]. In the last decades several technological advances were made in the field of laser Doppler vibrometry. The result is that nowadays, velocity measurements of fluids (using LDA) and vibrating objects (using LDV) are performed in many challenging applications in different fields (microelectronics, civil structures, biomedical engineering, material science, etc.).

  14. Glare Spot Phase Doppler Anemometry

    OpenAIRE

    Hespel, Camille; Ren, Kuan Fang; Gréhan, Gérard; Onofri, Fabrice

    2006-01-01

    International audience; The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index is also necessary since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemo...

  15. Radar Doppler Processing with Nonuniform Sampling.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Conventional signal processing to estimate radar Doppler frequency often assumes uniform pulse/sample spacing. This is for the convenience of t he processing. More recent performance enhancements in processor capability allow optimally processing nonuniform pulse/sample spacing, thereby overcoming some of the baggage that attends uniform sampling, such as Doppler ambiguity and SNR losses due to sidelobe control measures.

  16. Doppler echocardiography in pediatric cardiology

    International Nuclear Information System (INIS)

    Allen, H.D.; Marx, G.R.

    1986-01-01

    Congenital heart disease encompasses abnormalities in cardiac development which generally have in common either valve stenoses or connections between chambers or great vessels. Usually, abnormalities of intracardiac anatomy, and often, abnormalities of great vessel anatomy, can be unraveled by two-dimensional echocardiography. However, echocardiography offers little information regarding flow characteristics in the various congenital lesions. Addition of the Doppler principle, particularly when combined with the two-dimensional examination, can characterize the source of a flow disturbance, quantify gradients across a site of obstruction, and quantify flow volume across sites where flow is nonturbulent. These features make Doppler echocardiography unique for noninvasive accurate evaluation of children and adults with various forms of congenital heart disease. In this report, the authors discuss some of the present uses of Doppler echocardiography in congenital heart disease. Application of this technique requires greater understanding of certain physics principles than does routine echocardiography

  17. Doppler ultrasound scan during normal gestation: umbilical circulation; Ecografia Doppler en la gestacion normal: circulacion umbilical

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J. [Hospital Virgen Macarena. Sevilla (Spain)

    2002-07-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs.

  18. Longitudinal study of aortic isthmus Doppler in appropriately grown and small-for-gestational-age fetuses with normal and abnormal umbilical artery Doppler.

    LENUS (Irish Health Repository)

    Kennelly, M M

    2012-04-01

    To establish reference ranges using longitudinal data for aortic isthmus (AoI) Doppler indices in appropriate-for-gestational-age (AGA) fetuses and to document the longitudinal trends in a cohort of small-for-gestational-age (SGA) fetuses with normal umbilical artery Doppler and in fetuses with intrauterine growth restriction (IUGR) and abnormal umbilical artery Doppler.

  19. Musculoskeletal colour/power Doppler in sports medicine

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, M; Langberg, Henning

    2010-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  20. Temporal enhancement of two-dimensional color doppler echocardiography

    Science.gov (United States)

    Terentjev, Alexey B.; Settlemier, Scott H.; Perrin, Douglas P.; del Nido, Pedro J.; Shturts, Igor V.; Vasilyev, Nikolay V.

    2016-03-01

    Two-dimensional color Doppler echocardiography is widely used for assessing blood flow inside the heart and blood vessels. Currently, frame acquisition time for this method varies from tens to hundreds of milliseconds, depending on Doppler sector parameters. This leads to low frame rates of resulting video sequences equal to tens of Hz, which is insufficient for some diagnostic purposes, especially in pediatrics. In this paper, we present a new approach for reconstruction of 2D color Doppler cardiac images, which results in the frame rate being increased to hundreds of Hz. This approach relies on a modified method of frame reordering originally applied to real-time 3D echocardiography. There are no previous publications describing application of this method to 2D Color Doppler data. The approach has been tested on several in-vivo cardiac 2D color Doppler datasets with approximate duration of 30 sec and native frame rate of 15 Hz. The resulting image sequences had equivalent frame rates to 500Hz.

  1. Doppler US evaluation of the hypertensive portal system

    International Nuclear Information System (INIS)

    Needleman, L.; Kurtz, A.B.; Bezzi, M.; Rifkin, M.D.; Pasto, M.E.; Pennell, R.G.; Baltarowich, O.H.; Goldberg, B.B.

    1986-01-01

    In patients with known portal hypertension, pulsed Doppler US was used for qualitative and directional evaluation of flow in the portal venous system and collateral vessels. Most patients had normal hepatopetal flow. Doppler US revealed the following abnormal blood flow patterns: hepatofugal portal flow, bidirectional portal flow, intrahepatic portal shunting, flow in portasystemic collaterals, and hepatic vein obstruction. Doppler US can provide important clinical information in the evaluation of portal hypertension

  2. The image of urachus adenocarcinoma on Doppler ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Oyar, Orhan E-mail: o_oyar@hotmail.com; Yesildag, Ahmet; Gulsoy, Ufuk Kemal; Perk, Hakki

    2002-10-01

    Malignant urachal lesions are exceedingly rare and occur predominantly in adult life. In this case report, an adult patient with urachal carcinoma is presented with abdominal plain film, intravenous urography, gray-scale ultrasonography (US), Doppler US, and computed tomography (CT). Doppler US successfully showed the neovascularity with low resistive index value in the urachus tumor. We believe that Doppler US examination is helpful in the differential diagnosis of urachal carcinoma.

  3. Doppler coefficient measurements in Zebra Core 5

    International Nuclear Information System (INIS)

    Baker, A.R.; Wheeler, R.C.

    1965-11-01

    Measurements using a central hot loop in Zebra Core 5 are described. Results are given for the Doppler coefficients found in a number of assemblies with PuO 2 and 16% PuO 2 /84% depleted UO 2 pins, loaded with different combinations of steel, sodium or void pins. The mixed oxide results are in general about 20% more negative than was calculated using the FD2 data set, but agreement is good if the plutonium contributions in the calculations are omitted. The small positive Doppler coefficient calculated for Pu239 was not observed, and two measurements indicated instead a small negative effect. The Doppler effect in the mixed oxide systems was found to vary approximately as 1/T. The results from the empty loop and non-fissile assemblies indicate either a small negative Doppler effect in steel or alternatively the presence of an unexplained expansion effect. (author)

  4. Analysis of Radar Doppler Signature from Human Data

    Directory of Open Access Journals (Sweden)

    M. ANDRIĆ

    2014-04-01

    Full Text Available This paper presents the results of time (autocorrelation and time-frequency (spectrogram analyses of radar signals returned from the moving human targets. When a radar signal falls on the human target which is moving toward or away from the radar, the signals reflected from different parts of his body produce a Doppler shift that is proportional to the velocity of those parts. Moving parts of the body causes the characteristic Doppler signature. The main contribution comes from the torso which causes the central Doppler frequency of target. The motion of arms and legs induces modulation on the returned radar signal and generates sidebands around the central Doppler frequency, referred to as micro-Doppler signatures. Through analyses on experimental data it was demonstrated that the human motion signature extraction is better using spectrogram. While the central Doppler frequency can be determined using the autocorrelation and the spectrogram, the extraction of the fundamental cadence frequency using the autocorrelation is unreliable when the target is in the clutter presence. It was shown that the fundamental cadence frequency increases with increasing dynamic movement of people and simultaneously the possibility of its extraction is proportional to the degree of synchronization movements of persons in the group.

  5. Evaluating Peripheral Vascular Injuries: Is Color Doppler Enough for Diagnosis?

    Directory of Open Access Journals (Sweden)

    Mohd Lateef Wani

    2014-03-01

    Full Text Available Background:: Vascular injury poses a serious threat to limb and life. Thus, diagnosis should be made immediately with minimally invasive methods. Doppler is a good aid in diagnosis of vascular injury. Methods:: The present prospective study was conducted on 150 patients who presented with soft signs (the signs which are suggestive but not confirmatory of vascular injury. They were subjected to color Doppler examination before exploration. The patients with the features of vascular injury on color Doppler were subjected to exploration. On the other hand, those who had normal Doppler were subjected to CT- angiography. Then, the findings of the exploration were matched with those of color Doppler. The data were analyzed using the SPSS statistical software. Results:: Out of the 150 Doppler examinations, 110 (73.33% were reported as positive, while 40 were reported as negative for vascular injury. These were subjected to CT-angiography and seven of them had the features of vascular injury on CT-angiography. All the patients with positive Doppler or CT angiography findings were subjected to exploration. Doppler had a sensitivity of 94% and specificity of 82.5% in diagnosis of vascular injury using Binary classification test. Conclusions:: Color Doppler is an easily available, reliable, and handy method of diagnosing a vascular injury. It has a very high sensitivity and specificity in diagnosis of vascular injuries.

  6. Sub-Doppler laser cooling of potassium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Landini, M. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); INFN, Sezione di Firenze, I-50019 Sesto Fiorentino (Italy); Dipartimento di fisica, Universita di Trento, I-38123 Povo (Trento) (Italy); Roy, S.; Carcagni, L.; Trypogeorgos, D. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); Fattori, M.; Inguscio, M.; Modugno, G. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); INFN, Sezione di Firenze, I-50019 Sesto Fiorentino (Italy)

    2011-10-15

    We investigate the sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead that the combination of a dark optical molasses scheme that naturally arises in this kind of system and an adiabatic ramping of the laser parameters allows us to reach sub-Doppler temperatures for small laser detunings. We demonstrate temperatures as low as 25{+-}3 {mu}K and 47{+-}5 {mu}K in high-density samples of the two isotopes {sup 39}K and {sup 41}K, respectively. Our findings should find application to other atomic systems.

  7. Sub-Doppler laser cooling of potassium atoms

    International Nuclear Information System (INIS)

    Landini, M.; Roy, S.; Carcagni, L.; Trypogeorgos, D.; Fattori, M.; Inguscio, M.; Modugno, G.

    2011-01-01

    We investigate the sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead that the combination of a dark optical molasses scheme that naturally arises in this kind of system and an adiabatic ramping of the laser parameters allows us to reach sub-Doppler temperatures for small laser detunings. We demonstrate temperatures as low as 25±3 μK and 47±5 μK in high-density samples of the two isotopes 39 K and 41 K, respectively. Our findings should find application to other atomic systems.

  8. Methodology for obtaining wind gusts using Doppler lidar

    DEFF Research Database (Denmark)

    Suomi, Irene; Gryning, Sven-Erik; O'Connor, Ewan J.

    2017-01-01

    reduced the bias in the Doppler lidar gust factors from 0.07 to 0.03 and can be improved further to reduce the bias by using a realistic estimate of turbulence. Wind gust measurements are often prone to outliers in the time series, because they represent the maximum of a (moving-averaged) horizontal wind...... detection also outperformed the traditional Doppler lidar quality assurance method based on carrier-to-noise ratio, by removing additional unrealistic outliers present in the time series.......A new methodology is proposed for scaling Doppler lidar observations of wind gusts to make them comparable with those observed at a meteorological mast. Doppler lidars can then be used to measure wind gusts in regions and heights where traditional meteorological mast measurements are not available...

  9. Evaluation of left ventricular diastolic echocardiographic parameters in healthy dogs by pulsed-wave Doppler Avaliação de parâmetros ecocardiográficos diastólicos do ventrículo esquerdo de cães saudáveis por meio de Doppler pulsátil

    Directory of Open Access Journals (Sweden)

    Guilherme G. Pereira

    2009-04-01

    Full Text Available Left ventricular diastolic dysfunction plays an important role on heart failure progression. In order to obtain additional reference values of left ventricular diastolic parameters and investigate influence of common variables, peak E wave (peak E, peak A wave (peak A, E/A ratio (E/A, E wave deceleration time (EDT and isovolumic relaxation time (IRVT were studied in 40 clinically healthy dogs, by pulsed wave Doppler. The following values were obtained: peak E = 0.747 ± 0.117 m/s, peak A = 0.487 ± 0.062 m/s, E/A = 1.533 ± 0.198, EDT = 88.7 ± 9.2 ms and IRVT = 0.080 ± 0.009 s. Some parameters were influenced by heart rate (peak E, peak A and IRVT, by age (peak A and E/A and by body weight (TRIV. Gender influence was absent. Values obtained can be used as reference for canine specimens but its interpretation should consider on the influence of related variables.A disfunção diastólica do ventrículo esquerdo contribui de maneira importante para a progressão da insuficiência cardíaca. No intuito de obter valores de referência adicionais para os parâmetros diastólicos do ventrículo esquerdo e para investigar a influência de variáveis comuns, estudou-se, por meio de Doppler pulsátil, a velocidade máxima da onda E (Vmáx.E, a velocidade máxima da onda A (Vmáx.: A, a relação E/A (E/A, o tempo de desaceleração da onda E (TDE e o tempo de relaxamento isovolumétrico (TRIV em 40 cães clinicamente saudáveis. Os seguintes valores foram obtidos: Vmáx.E = 0,747±0,117m/s, Vmáx.A = 0,487±0,062m/s, E/A = 1,533±0,198, TDE = 88,7±9,2ms e TRIV = 0,080±0,009s. Alguns parâmetros foram influenciados pela freqüência cardíaca (Vmáx.E, Vmáx.A e TRIV, pela idade (Vmáx.A e E/A e pelo peso corpóreo (TRIV. Não houve influência pelo sexo. Os valores obtidos podem ser utilizados como referência para a espécie canina, porém devem ser interpretados considerando-se a influência das variáveis descritas.

  10. Corruption of radio metric Doppler due to solar plasma dynamics: S/X dual-frequency Doppler calibration for these effects

    Science.gov (United States)

    Winn, F. B.; Reinbold, S. R.; Yip, K. W.; Koch, R. E.; Lubeley, A.

    1975-01-01

    Doppler data from Mariner 6, 7, 9, and 10 and Pioneer 10 and 11 were discussed and the rms noise level for various sun-earth-probe angles were shown. The noise levels of both S- and X-band Doppler data for sun-earth-probe angles smaller than 20 deg were observed to be orders of magnitude greater than nominal. Such solar plasma-related Doppler degradation reduced the Mariner 10-Mercury 11 encounter navigation accuracy by nearly a factor of 10. Furthermore, this degradation was shown to be indirectly related to plasma dynamics and not a direct measure of the dynamics.

  11. Avaliação por imagem do comprometimento osteoarticular e de nervos periféricos na hanseníase Imaging methods evaluation in osteoarticular and peripheral nerves involvement in leprosy

    Directory of Open Access Journals (Sweden)

    Helena Lúcia Alves Pereira

    2006-06-01

    Full Text Available Na hanseníase, lesões ósseas por invasão direta do bacilo são de baixa incidência, e os achados radiológicos destas lesões são de osteomielite aguda ou crônica similares aos de outras infecções granulomatosas. As lesões ósseas mais comuns são devidas ao trauma e a infecção secundária nos tecidos denervados. Radiograficamente, são observados vários graus de reabsorção das extremidades distais envolvendo mãos e pés, ocasionando perda dos dígitos e osteoartropatia neuropática de pequenas articulações. Os achados radiológicos são semelhantes às outras condições nas quais há déficit sensorial, como esclerodermia, siringomielia e diabetes mellitus. A ultra-sonografia (US e a ressonância magnética (RM podem ser úteis na avaliação do comprometimento dos nervos periféricos auxiliando no diagnóstico das neurites, abscessos e no diagnóstico diferencial das síndromes compressivas.In leprosy, bone lesions due direct invasion of bacilli are low in incidence and these lesions exhibit radiologic findings of acute and chronic osteomyelitis similar to those of other granulomatous infectious agents. The more common bone lesions are those due to injurious effects of trauma and infection imposed upon denervated tissues. Radiographycally are seen various degrees of reabsorption of the extremities involving hands and feet with the loss of digits and disorganizing arthropathies in small joints. The radiologic appearance are similar to other conditions in which there is sensory impairment like scleroderma, syringomielia and diabetes mellitus. The ultrasonography and magnetic resonance imaging (MRI can be helpful in evaluation of the involvement of the peripheral nerves helping in the diagnosis of the neuritis, abscess and differential diagnosis in compressive syndromes.

  12. Ultrasonography findings of musculotendinous lesions of the shoulder

    OpenAIRE

    Zorzetto, Arquimedes Artur; Urban, Linei Augusta Brolini Dellê; Liu, Christian Bark; Prevedello, Luciano; Zapparoli, Mauricio; Vitola, Maria Luiza Amalfi; Awamura, Yumi; Pedro, Mônica Simeão; Nascimento, Alessandra Bettega

    2003-01-01

    Este estudo propôs-se a revisar os aspectos relevantes da anatomia, técnica de exame e achados de imagens, com o objetivo de auxiliar o radiologista no diagnóstico diferencial frente às afecções músculo-tendinosas do ombro. Foram realizadas 34 ultra-sonografias da região do ombro, no período de janeiro a dezembro de 2001. A avaliação foi realizada com transdutores de alta freqüência (7,5-10 MHz). O exame foi normal em 23% dos pacientes (oito casos). Dos 26 casos alterados, observaram-se oito ...

  13. Forma atípica de tireoidite supurativa aguda em paciente pediátrico: relato de caso

    OpenAIRE

    Torres, Maria Rosineide dos S.; Medeiros, Carla C. M.; Nóbrega Neto, Sebastião Horácio; Souza, Lincoln S.; Rodrigues, Mônica L. C.; Silva, Maria Nelice M.; Maior, Lyzandra de H. C. S.; Avelino, Márcia C.; Mourão, Germana T. F.

    2008-01-01

    A tireoidite aguda é uma doença rara. Na infância associa-se principalmente a anormalidades congênitas com acometimento do lobo esquerdo. Na ausência de tireoidopatia preexistente, a função tireoidiana geralmente está normal. Relatamos um caso de uma menina, 6 anos de idade, com tumoração associada a sinais flogísticos na região cervical anterior há 15 dias acompanhada de leucocitose com desvio à esquerda, VSH e TSH elevados. Não havia história prévia de tireoidopatia. A ultra-sonografia da r...

  14. Sun Ultra 5

    CERN Multimedia

    1998-01-01

    The Sun Ultra 5 is a 64-bit personal computer based on the UltraSPARC microprocessor line at a low price. The Ultra 5 has been declined in several variants: thus, some models have a processor with less cache memory to further decrease the price of the computer.

  15. Doppler Velocity Signatures of Idealized Elliptical Vortices

    Directory of Open Access Journals (Sweden)

    Wen-Chau Lee

    2006-01-01

    Full Text Available Doppler radar observations have revealed a class of atmospheric vortices (tropical cyclones, tornadoes, dust devils that possess elliptical radar reflectivity signatures. One famous example is Typhoon Herb (1996 that maintained its elliptical reflectivity structure over a 40-hour period. Theoretical work and dual-Doppler analyses of observed tropical cyclones have suggested two physical mechanisms that can explain the formation of two types of elliptical vortices observed in nature, namely, the combination of a circular vortex with either a wavenumber two vortex Rossby wave or a deformation field. The characteristics of these two types of elliptical vortices and their corresponding Doppler velocity signatures have not been previously examined.

  16. TCSP ER-2 DOPPLER RADAR (EDOP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The EDOP provides vertically profiled reflectivity and Doppler velocity at aircraft nadir along the flight track. The ER-2 Doppler radar (EDOP) is an X-band (9.6...

  17. Gold nanorods as a contrast agent for Doppler optical coherence tomography.

    Directory of Open Access Journals (Sweden)

    Bo Wang

    Full Text Available To investigate gold nanorods (GNRs as a contrast agent to enhance Doppler optical coherence tomography (OCT imaging of the intrascleral aqueous humor outflow.A serial dilution of GNRs was scanned with a spectral-domain OCT device (Bioptigen, Durham, NC to visualize Doppler signal. Doppler measurements using GNRs were validated using a controlled flow system. To demonstrate an application of GNR enhanced Doppler, porcine eyes were perfused at constant pressure with mock aqueous alone or 1.0×10(12 GNR/mL mixed with mock aqueous. Twelve Doppler and volumetric SD-OCT scans were obtained from the limbus in a radial fashion incremented by 30°, forming a circular scan pattern. Volumetric flow was computed by integrating flow inside non-connected vessels throughout all 12 scans around the limbus.At the GNR concentration of 0.7×10(12 GNRs/mL, Doppler signal was present through the entire depth of the testing tube without substantial attenuation. A well-defined laminar flow profile was observed for Doppler images of GNRs flowing through the glass capillary tube. The Doppler OCT measured flow profile was not statistically different from the expected flow profile based upon an autoregressive moving average model, with an error of -0.025 to 0.037 mm/s (p = 0.6435. Cross-sectional slices demonstrated the ability to view anterior chamber outflow ex-vivo using GNR-enhanced Doppler OCT. Doppler volumetric flow measurements were comparable to flow recorded by the perfusion system.GNRs created a measureable Doppler signal within otherwise silent flow fields in OCT Doppler scans. Practical application of this technique was confirmed in a constant pressure ex-vivo aqueous humor outflow model in porcine eyes.

  18. GRIP DOPPLER AEROSOL WIND LIDAR (DAWN) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Doppler Aerosol WiNd Lidar (DAWN) Dataset was collected by the Doppler Aerosol WiNd (DAWN), a pulsed lidar, which operated aboard a NASA DC-8 aircraft...

  19. Diabetic Nephropathy : Evaluation with Doppler Ultrasonography

    International Nuclear Information System (INIS)

    Sim, Jung Suk; Kim, Seung Hyup; Kang, Heung Sik; Park, Jae Hyung; Han, Man Chung

    1996-01-01

    To compare Doppler ultrasonography with laboratory tests in evaluation of diabetic nephropathy. Fifty-five patients (mean age = 60, M : F = 26 : 29) with diabetes mellitus underwent renal Doppler ultrasonography. Resistive indices were compared with degree of proteinuria, serum creatinine level, and creatinine clearance rate. Eighteen patients who showed no proteinuria or microscopic proteinuria had a mean resistive index (RI) of 0.72 (SD, 0.05), 16 patients with macroscopic proteinuria without nephrotic syndrome had a mean RI of 0.82 (SD, 0.13), and 21 patients with nephrotic syndrome had a mean RI of 0.90 (SD, 0.12). Renal RI correlated highly with serum creatinine level (r = 0.62) and creatinine clearance rate (r = -0.43). Renal Doppler ultrasonography provides a useful indication of renal function in diabetic nephropathy but cannot offer an advantage over conventional laboratory test

  20. Use of Doppler ultrasound for non-invasive urodynamic diagnosis

    Directory of Open Access Journals (Sweden)

    Hideo Ozawa

    2009-01-01

    Full Text Available Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1 and the sphincteric urethra (V2 were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1, calculated by Q max /V1, was lower in the group of bladder outlet obstruction (BOO vs. control group. Velocity ratio (VR, which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS will dramatically expand the information on voiding function.

  1. Wide Angle Michelson Doppler Imaging Interferometer (WAMDII)

    Science.gov (United States)

    Roberts, B.

    1986-01-01

    The wide angle Michelson Doppler imaging interferometer (WAMDII) is a specialized type of optical Michelson interferometer working at sufficiently long path difference to measure Doppler shifts and to infer Doppler line widths of naturally occurring upper atmospheric Gaussian line emissions. The instrument is intended to measure vertical profiles of atmospheric winds and temperatures within the altitude range of 85 km to 300 km. The WAMDII consists of a Michelson interferometer followed by a camera lens and an 85 x 106 charge coupled device photodiode array. Narrow band filters in a filter wheel are used to isolate individual line emissions and the lens forms an image of the emitting region on the charge coupled device array.

  2. Temporal Doppler Effect and Future Orientation: Adaptive Function and Moderating Conditions.

    Science.gov (United States)

    Gan, Yiqun; Miao, Miao; Zheng, Lei; Liu, Haihua

    2017-06-01

    The objectives of this study were to examine whether the temporal Doppler effect exists in different time intervals and whether certain individual and environmental factors act as moderators of the effect. Using hierarchical linear modeling, we examined the existence of the temporal Doppler effect and the moderating effect of future orientation among 139 university students (Study 1), and then the moderating conditions of the temporal Doppler effect using two independent samples of 143 and 147 university students (Studies 2 and 3). Results indicated that the temporal Doppler effect existed in all of our studies, and that future orientation moderated the temporal Doppler effect. Further, time interval perception mediated the relationship between future orientation and the motivation to cope at long time intervals. Finally, positive affect was found to enhance the temporal Doppler effect, whereas control deprivation did not influence the effect. The temporal Doppler effect is moderated by the personality trait of future orientation and by the situational variable of experimentally manipulated positive affect. We have identified personality and environmental processes that could enhance the temporal Doppler effect, which could be valuable in cases where attention to a future task is necessary. © 2016 Wiley Periodicals, Inc.

  3. TRIPLEX DOPPLER DA ARTÉRIA HEPÁTICA CANINA NOS PERÍODOS PRÉ E PÓS-PRANDIAL TRIPLEX DOPPLER OF CANINE HEPATIC ARTERY ON PRE AND POSPRANDIAL PERIODS

    Directory of Open Access Journals (Sweden)

    Elizabete Nikolak Nikolak

    2009-09-01

    Full Text Available O objetivo deste trabalho foi avaliar por meio do triplex doppler as varia��ões dos índices de resistividade (IR e pulsatilidade (IP da artéria hepática (AH de cães adultos saudáveis em períodos pré e pós-prandiais. O grupo amostral foi composto por quatorze cães sem raça definida, sendo nove fêmeas e cinco machos com peso entre seis e dezenove quilos e quatro e dezesseis quilos, respectivamente. Previamente aos exames ultrassonográficos, os animais foram submetidos a 24 horas de jejum e, para os exames pós-prandiais, foram alimentados com leite ou ração comercial. Utilizou-se o ultrassom Philips HDI 4000, munido de um transdutor microconvexo (5-8MHz. Dividiram-se as mensurações dos IR e IP da AH em três tempos: T0 (período pré-prandial, T1 (trinta minutos pós-prandial e T2 (noventa minutos pós-prandial. Não houve diferença estatística quando comparadas as médias de IR e IP da AH entre T0 e T2. No entanto, ambos os índices foram significativamente menores no T1 quando comparado com os outros períodos de análise, comprovando aumento de fluxo sanguíneo na AH trinta minutos pós-prandial. O uso do triplex doppler da AH possibilitou mensurações do fluxo sanguíneo pré e pós-prandial, sendo uma técnica importante para estabelecer parâmetros comparativos entre homeostasia metabólica e diferentes estados fisiopatológicos hepáticos.

    PALAVRAS-CHAVES: Artéria hepática, cães, índice de resistividade, índice de pulsatilidade, ultrassonografia. The aim of the current study was to evaluate the resistivity index (RI and pulsatility index (PI of hepatic artery (HA by Triplex Doppler in health adult dogs on pre and postprandial periods. The experimental group was formed by 14 mongrel dogs, 9 females and five males, weighing 6-19 kg and 4-16 kg, respectively. The animals were previously prepared, remaining 24 hours of starvation, and feeding with milk or pellet show food to perform posprandial analysis

  4. Calculation of the Doppler broadening function using Fourier analysis

    International Nuclear Information System (INIS)

    Goncalves, Alessandro da Cruz

    2010-01-01

    An efficient and precise method for calculation of Doppler broadening function is very important to obtain average group microscopic cross sections, self shielding factors, resonance integrals and others reactor physics parameter. In this thesis two different methods for calculation of Doppler broadening function and interference term will be presented. The main method is based on a new integral form for Doppler broadening function ψ(x,ζ) which gives a mathematical interpretation of the approximation proposed by Bethe and Placzek, as the convolution of the Lorentzian function with a Gaussian function. This interpretation besides leading to a new integral form for ψ(x,ζ), enables to obtain a simple analytic solution for the Doppler broadening function. (author)

  5. New clutter-rejection algorithm for Doppler ultrasound

    Science.gov (United States)

    Cloutier, Guy; Chen, Danmin; Durand, Louis-Gilles

    2002-04-01

    Several strategies, known as clutter or wall Doppler filtering, were proposed to remove the strong echoes produced by stationary or slow moving tissue structures from the Doppler blood flow signal. In this study, the matching pursuit (MP) method is proposed to remove clutter components. The MP method decomposes the Doppler signal into wavelet atoms that are selected in a decreasing energy order. Thus, the high-energy clutter components are extracted first. In the present study, the pulsatile Doppler signal s(n) was simulated by a sum of random-phase sinusoids. Two types of high-amplitude clutter signals were then superimposed on s(n): a time-varying low frequency component (type 1), covering systole and early diastole, and short transient clutter signals (type 2), distributed within the whole cardiac cycle. The Doppler signals were modeled with the MP method and the most dominant atoms were subtracted until the signal-to-clutter (S/C) ratio reached a maximum. For the type 1 clutter signal, the improvement in the S/C ratio was 19.0 +/- 0.6 dB, and 72.0 +/- 4.5 atoms were required to reach this performance. For the transient type 2 clutter signal, exactly 10 atoms were required and the maximum improvement in S/C ratio was 5.5 +/- 0.5 dB. These results suggest the possibility of using this signal processing approach to implement clutter rejection filters on ultrasound commercial instruments.

  6. Inline Ultrasonic Rheometry by Pulsed Doppler

    Energy Technology Data Exchange (ETDEWEB)

    Pfund, David M.; Greenwood, Margaret S.; Bamberger, Judith A.; Pappas, Richard A.

    2006-12-22

    This will be a discussion of the non-invasive determination of the viscosity of a non-Newtonian fluid in laminar pipe flow over the range of shear rates present in the pipe. The procedure used requires knowledge of the flow profile in and the pressure drop along a long straight run of pipe. The profile is determined by using a pulsed ultrasonic Doppler velocimeter. This approach is ideal for making non-invasive, real-time measurements for monitoring and control. Rheograms of a shear thinning, thixotropic gel will be presented. The operating parameters and limitations of the Doppler-based instrument will be discussed. The most significant limitation is velocity gradient broadening of the Doppler spectra near the walls of the pipe. This limitation can be significant for strongly shear thinning fluids (depending also on the ratio of beam to pipe diameter and the transducer's insertion angle).

  7. Molecules cooled below the Doppler limit

    Science.gov (United States)

    Truppe, S.; Williams, H. J.; Hambach, M.; Caldwell, L.; Fitch, N. J.; Hinds, E. A.; Sauer, B. E.; Tarbutt, M. R.

    2017-12-01

    Magneto-optical trapping and sub-Doppler cooling have been essential to most experiments with quantum degenerate gases, optical lattices, atomic fountains and many other applications. A broad set of new applications await ultracold molecules, and the extension of laser cooling to molecules has begun. A magneto-optical trap (MOT) has been demonstrated for a single molecular species, SrF, but the sub-Doppler temperatures required for many applications have not yet been reached. Here we demonstrate a MOT of a second species, CaF, and we show how to cool these molecules to 50 μK, well below the Doppler limit, using a three-dimensional optical molasses. These ultracold molecules could be loaded into optical tweezers to trap arbitrary arrays for quantum simulation, launched into a molecular fountain for testing fundamental physics, and used to study collisions and chemistry between atoms and molecules at ultracold temperatures.

  8. Doppler ultrasound imaging techniques for assessment of synovial inflammation

    Directory of Open Access Journals (Sweden)

    Filippucci E

    2013-09-01

    Full Text Available Emilio Filippucci,1 Fausto Salaffi,1 Marina Carotti,2 Walter Grassi1 1Rheumatology Department, Polytechnic University of the Marche, Ancona, Italy; 2Department of Radiology, Polytechnic University of the Marche, Ancona, Italy Abstract: Ultrasound is an evolving technique, and the rapid progress made in ultrasound technology over the past ten years has dramatically increased its range of applications in rheumatology. One of the most exciting advances is the use of Doppler ultrasound imaging in the assessment of blood flow abnormalities at the synovial tissue level in patients with chronic inflammatory arthritis. This review describes the Doppler techniques available and their main applications in patients with inflammatory arthritis, discusses the evidence supporting their use, and outlines the latest advances in hardware and software. Spectral, color, and power Doppler allow sensitive assessment of vascular abnormalities at the synovial tissue level. Use of contrast agents enhances visualization of the small synovial vessels using color or power Doppler ultrasound and allows for accurate characterization of the rheumatoid pannus. Doppler techniques represent a unique method for assessment of synovial inflammation, showing blood flow characteristics in real time. They are safe, noninvasive, cost-effective, and have high sensitivity in revealing and monitoring synovitis. However, several questions still need to be answered. In the near future, the Doppler techniques described here, together with upcoming hardware and software facilities, will be investigated further and a consensus will be reached on their feasibility and appropriate use in daily rheumatologic practice. Keywords: power and color Doppler techniques, ultrasound, contrast media, synovitis, rheumatoid arthritis

  9. Doppler Shift Compensation Schemes in VANETs

    Directory of Open Access Journals (Sweden)

    F. Nyongesa

    2015-01-01

    Full Text Available Over the last decade vehicle-to-vehicle (V2V communication has received a lot of attention as it is a crucial issue in intravehicle communication as well as in Intelligent Transportation System (ITS. In ITS the focus is placed on integration of communication between mobile and fixed infrastructure to execute road safety as well as nonsafety information dissemination. The safety application such as emergence alerts lays emphasis on low-latency packet delivery rate (PDR, whereas multimedia and infotainment call for high data rates at low bit error rate (BER. The nonsafety information includes multimedia streaming for traffic information and infotainment applications such as playing audio content, utilizing navigation for driving, and accessing Internet. A lot of vehicular ad hoc network (VANET research has focused on specific areas including channel multiplexing, antenna diversity, and Doppler shift compensation schemes in an attempt to optimize BER performance. Despite this effort few surveys have been conducted to highlight the state-of-the-art collection on Doppler shift compensation schemes. Driven by this cause we survey some of the recent research activities in Doppler shift compensation schemes and highlight challenges and solutions as a stock-taking exercise. Moreover, we present open issues to be further investigated in order to address the challenges of Doppler shift in VANETs.

  10. Contrast-enhanced power Doppler US in the characterization of renal masses; Power Doppler con mezzo di contrasto nella caratterizzazione delle masse renali

    Energy Technology Data Exchange (ETDEWEB)

    Ascenti, G.; Zimbaro, G.; Mazziotti, S.; Visalli, C.; Racchiusa, S.; Vinci, S.; Scribano, E. [Messina Univ., Messina (Italy). Ist. di Scienze Radiologiche

    2000-09-01

    Purpose of this work is to report the results of a prospective study investigating the potentials of contrast-enhanced power Doppler in the diagnosis of expansive renal lesions. From 1997 to October 30, 1999, it was studied the case of 59 expansive renal lesions (28 malignant, 31 benign) in 48 patients (mean age 55 years, range 10-79) with power Doppler US before and after the administration of an echo-enhancing agent (Levovist, Schering AG, Berlin Germany). Were found 5 patterns of vascular architecture of the lesions, both before and after contrast agent administration, following the classification by Jinzaki e Coll. Power Doppler US showed vascular structures in 34 patients. The administration of Levovist revealed vessels in 12/25 lesions which had none at baseline studies and in 6 cases vascularity was particularly evident. Color signals were enhanced in all the 34 vascularized lesions, which allowed better definition of vascular patterns. The characterization of vascular patterns with baseline power Doppler US helped improve diagnostic accuracy compared to gray-scale US (58% versus 32%) for hyperechoic lesions, complex cysts and pseudomasses. Independent of contrast agent administration, the integration of gray-scale and power Doppler modes increased diagnostic accuracy even further (76% correct diagnoses). In our series, the US contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions; conversely, Levovist can be advantageous for the characterization of suspected pseudomasses and complex cysts. [Italian] Scopo di questo articolo e' quello di riportare i risultati di uno studio prospettico finalizzato ad individuare le potenzialita' del power Doppler con mdc ecografico nella caratterizzazione delle lesioni espansive del rene. Dal 1997 al 30 ottobre 1999 sono state studiate 59 lesioni renali (28 maligne, 31 benigne) in 48 pazienti (eta' media 55 anni, intervallo 10

  11. Comparison between Doppler Ultrasound and Biopsy Findings in ...

    African Journals Online (AJOL)

    Methods: We retrospectively studied a random sample of 188 kidney transplanted patients who had Doppler-ultrasound examination followed within two weeks by transplant biopsy. We evaluated the specificity and sensitivity of Doppler ultrasound in diagnosing rejection at different RI thresholds, using the reported biopsy ...

  12. Acute intrascrotal pathology in childhood: color Doppler study

    International Nuclear Information System (INIS)

    Cinta Sanguesa, C.; Muro, D.; Cortina, H.; Moreno, A.

    1997-01-01

    To asses the utility of color Doppler ultrasound in the study of acute intrascrotal pathology in childhood. Seventy-five boys with evidence of an acute intrascrotal abnormality were studied by means of color Doppler ultrasound. A 7.5 MHz linear transducer was used. The most common findings was inflammatory disease (60%) which was indicated by the presence of hyperemia in color Doppler. Of the nine boys with testicular torsion (12%) two presented extravaginal torsion, with a complete absence of intratesticular vascularization. Intravaginal torsion was observed in seven patients, six of whom presented reduced vascularization in the abnormal testicle with respect to the healthy testicle. There was one false negative in which testicular vascularization was normal but 360 degree centigree torsion was found at surgery. In addition, there were seven cases of hydatid torsion (9.33%), four of idiopathic scrotal swelling (5.3%). two cases of intermittent torsion (2.6%) and one case of Shcolein-Henoch purpura (1.3%). The ultrasound findings were completely nornal in seven boys. Color Doppler is a rapid, noninvasive method for assessing testicular blood flow. The elevated sensitivity and specificity (85.7 and 100%, respectively, in our series) for testicular torsion make Doppler ultrasound a highly reliable method for the study of this disorder. (Author) 18 refs

  13. Nódulos benignos da mama: uma revisão dos diagnósticos diferenciais e conduta Benign breast masses: a review on diagnosis and management

    Directory of Open Access Journals (Sweden)

    Afonso Celso Pinto Nazário

    2007-04-01

    Full Text Available Os nódulos mamários benignos são responsáveis por até 80% das massas palpáveis. Seu diagnóstico diferencial é amplo, envolvendo os cistos mamários, os fibroadenomas, os tumores filóides, os papilomas, os lipomas, os hamartomas e os adenomas, entre outros. O fibroadenoma é a neoplasia mamária mais comum em pacientes menores de 35 anos e os cistos são mais freqüentes na perimenopausa. O diagnóstico diferencial entre nódulos sólidos ou císticos poderá ser feito por meio da punção aspirativa com agulha fina ou pela ultra-sonografia, sendo terapêutica para os últimos. Neste artigo serão revisados os aspectos diagnósticos diferenciais entre estes tumores e as novas abordagens terapêuticas.The benign mammary tumors are responsible for up to 80% of the clinical masses. Its differential diagnosis is wide, involving mammary cysts, fibroadenomas, phyllodes tumors, papillomas, hamartomas, and adenomas, among others. The fibroadenoma is the most common mammary neoplasia in patients under 35 years old, while the cysts are more frequent in the perimenopause. The differential diagnosis among solid or cystic nodules can be made through the fine-needle aspiration or by ultrasound, being therapeutic for the last ones. In this article, the differential diagnostic aspects will be revised between these tumors, as well as the new therapeutic approaches.

  14. Arm locking with Doppler estimation errors

    Energy Technology Data Exchange (ETDEWEB)

    Yu Yinan; Wand, Vinzenz; Mitryk, Shawn; Mueller, Guido, E-mail: yinan@phys.ufl.ed [Department of Physics, University of Florida, Gainesville, FL 32611 (United States)

    2010-05-01

    At the University of Florida we developed the University of Florida LISA Interferometer Simulator (UFLIS) in order to study LISA interferometry with hardware in the loop at a system level. One of the proposed laser frequency stabilization techniques in LISA is arm locking. Arm locking uses an adequately filtered linear combination of the LISA arm signals as a frequency reference. We will report about experiments in which we demonstrated arm locking using UFLIS. During these experiments we also discovered a problem associated with the Doppler shift of the return beam. The initial arm locking publications assumed that this Doppler shift can perfectly be subtracted inside the phasemeter or adds an insignificant offset to the sensor signal. However, the remaining Doppler knowledge error will cause a constant change in the laser frequency if unaccounted for. Several ways to circumvent this problem have been identified. We performed detailed simulations and started preliminary experiments to verify the performance of the proposed new controller designs.

  15. Low-Frequency Gravitational Wave Searches Using Spacecraft Doppler Tracking

    Directory of Open Access Journals (Sweden)

    Armstrong J. W.

    2006-01-01

    Full Text Available This paper discusses spacecraft Doppler tracking, the current-generation detector technology used in the low-frequency (~millihertz gravitational wave band. In the Doppler method the earth and a distant spacecraft act as free test masses with a ground-based precision Doppler tracking system continuously monitoring the earth-spacecraft relative dimensionless velocity $2 Delta v/c = Delta u/ u_0$, where $Delta u$ is the Doppler shift and $ u_0$ is the radio link carrier frequency. A gravitational wave having strain amplitude $h$ incident on the earth-spacecraft system causes perturbations of order $h$ in the time series of $Delta u/ u_0$. Unlike other detectors, the ~1-10 AU earth-spacecraft separation makes the detector large compared with millihertz-band gravitational wavelengths, and thus times-of-flight of signals and radio waves through the apparatus are important. A burst signal, for example, is time-resolved into a characteristic signature: three discrete events in the Doppler time series. I discuss here the principles of operation of this detector (emphasizing transfer functions of gravitational wave signals and the principal noises to the Doppler time series, some data analysis techniques, experiments to date, and illustrations of sensitivity and current detector performance. I conclude with a discussion of how gravitational wave sensitivity can be improved in the low-frequency band.

  16. Laser Doppler measurements in two-phase flows

    International Nuclear Information System (INIS)

    Durst, F.; Zare, M.

    1976-01-01

    Basic theory for laser-Doppler velocity measurements of large reflecting or refracting surfaces is provided. It is shown that the Doppler-signals contain information of the velocity and size of the large bodies, and relationships for transforming velocity and radius of curvature of moving spheres are presented. Preliminary experiments verified the analytical findings and demonstrated the applicability of the method to some two-phase flows

  17. Transversal Doppler-Fizeau effect

    International Nuclear Information System (INIS)

    Subacius, E.

    1981-01-01

    The relativistic calculation of the Doppler-Fizeau effect foresees a second grade redshift due to the proper time dilation of a moving object. The relevance of this relativistic effect on astrophysical observation is discussed, herein. (Auhor) [pt

  18. Operational Bright-Band Snow Level Detection Using Doppler Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A method to detect the bright-band snow level from radar reflectivity and Doppler vertical velocity data collection with an atmospheric profiling Doppler radar. The...

  19. Distribution of Doppler Redshifts of Associated Absorbers of SDSS ...

    Indian Academy of Sciences (India)

    The authors searched all ... quasar, where the contribution of the Doppler motion is relatively small. ..... might contribute to the Doppler redshift distribution. 5. ... out accounting for the contamination of intervening absorption systems, which can.

  20. Settings and artefacts relevant for Doppler ultrasound in large vessel vasculitis

    DEFF Research Database (Denmark)

    Terslev, L; Diamantopoulos, A P; Døhn, U Møller

    2017-01-01

    Ultrasound is used increasingly for diagnosing large vessel vasculitis (LVV). The application of Doppler in LVV is very different from in arthritic conditions. This paper aims to explain the most important Doppler parameters, including spectral Doppler, and how the settings differ from those used...

  1. Utilidad del índice de resistencia obtenido por ultrasonido Doppler en nódulos tiroideos de características ecográficas malignas.

    Science.gov (United States)

    Butrón-García, Ángel Fernando; Méndez-García, Mario

    2018-01-01

    La patología nodular tiroidea tiene alta prevalencia en la población general. Su diagnóstico se ha incrementado con el Doppler, con el cual se pueden detectar características sugerentes de malignidad, como elevación de los índices de resistencia y pulsatilidad. Evaluar la correlación de un índice de resistencia alto y los hallazgos histopatológicos en pacientes con sospecha ecográfica de nódulos tiroideos malignos. Estudio prospectivo, observacional, transversal y analítico de pruebas diagnósticas, en el Hospital de Especialidades 25, Monterrey, Nuevo León. Se incluyó a pacientes con nódulos tiroideos de características ecográficas malignas; se obtuvo el índice de resistencia de los nódulos, que se comparó con los hallazgos histopatológicos. Se incluyeron 48 pacientes con diagnóstico ecográfico de nódulo tiroideo maligno. La correlación de índices de resistencia elevados y diagnóstico histopatológico de nódulos tiroideos malignos fue significativa (p = 0.001). La sensibilidad fue de 73.3 %, y la especificidad de 78.7 %; valor predictivo positivo de 61.1 % y valor predictivo positivo negativo de 86.6 %. La determinación del índice de resistencia cada vez es más empleada, pero la sensibilidad y especificidad es baja y no es un método confiable, por lo que aún se requieren otros métodos complementarios. Thyroid nodular disease is highly prevalent in the general population. Its diagnosis has increased with Doppler ultrasound, by means of which features suggestive of malignancy can be detected, such as resistance and pulsatility indices elevation. To assess the correlation of a high resistance index and histopathological findings in patients with ultrasonographic suspicion of malignant thyroid nodules. Prospective, cross-sectional, analytic, observational study of diagnostic tests carried out at Specialty Hospital 25, in Monterrey, Nuevo León. Patients with thyroid nodules of ultrasonographic malignant characteristics were included

  2. [Diagnostic value of power Doppler ultrasonography for Sirenomelia Seguence in prenatal].

    Science.gov (United States)

    Yan, Xia-yu; Yang, Tai-zhu; Luo, Hong; Tian, Yu; Yang, Fan

    2011-11-01

    To study and discuss the diagnostic value and ultrasonographic characteristics of power doppler ultrasound in the prenatal diagnosis of Sirenomelia Seguence. The abdominal aorta in two fetuses with sirenomelia seguence fetuses and in ten with nomal was reviewed and compared with two-dimensional power doppler ultrasound and three-dimensional power doppler ultrasound in prenatal. The abdominal aorta were showed to divid into renal arteries in the kidney level while two common iliac arteries in the pelvis in nomal fetuses with two-dimensional power doppler ultrasound and three-dimensional power doppler ultrasound; compared with the nomal, the abdominal aorta and whose branches in sirenomelia seguence were demonstrated as follows: 1) a large and deformed vascular coming from the high abdominal aorta, which was found to act as a umbilical artery by careful examination; 2) no bifurcation of renal arteries identified; 3) no bifurcation of two common iliac arteries identified; 4) the abdominal aorta changing into a narrow vascular after one deformed vascular separating from. Sirenomelia seguence fetuses has a characteristic change in two-dimensional power doppler ultrasound and three-dimensional power doppler ultrasound, which is helpful to improve the prenatal diagnosis of sirenomelia seguence.

  3. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    International Nuclear Information System (INIS)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon

    2002-01-01

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  4. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  5. Three-gamma annihilation of ortho-positronium in NiO/γ-Al2O3 catalysts detected by positron lifetime and coincidence Doppler broadening measurements

    International Nuclear Information System (INIS)

    Huang, S.H.; Chen, Z.Q.; Zhang, H.J.

    2012-01-01

    The pore structure of NiO/γ-Al 2 O 3 catalysts is characterized by positron lifetime and Doppler broadening measurements. A very long lifetime τ 4 of 92 ns is resolved from the positron lifetime spectrum measured for pure Al 2 O 3 , which could be attributed to the ortho-positronium (o-Ps) lifetime in large pores. It was also found that the fitted lifetime τ 4 and its corresponding intensity I 4 obtained from the lifetime spectra both decrease with narrowing energy window of the stop channel in the fast–fast coincidence lifetime measurement system. This suggests that the ultra long lifetime is primarily due to the self annihilation of o-Ps which emits three gamma-rays. Such 3γ annihilation is further evidenced by measuring the Doppler broadening of annihilation gamma rays in coincidence with the prompt gamma rays (1.28 MeV) emitted from the 22 Na positron source. In NiO/γ-Al 2 O 3 catalysts both the lifetime τ 4 and its intensity I 4 decreases with increasing NiO content (from 3 wt% to 40 wt%), which indicates decreasing of the number of 3γ events. The 3γ annihilation parameter analyzed from the coincidence Doppler broadening spectrum shows consistent decrease with increasing NiO content. - Highlights: ► Above paper reported study of the 3-gamma annihilation of o-Ps. ► 3γ annihilation was verified by varying the energy window of the lifetime system. ► A new coincidence Doppler broadening technique is also used to record 3γ events. ► 3γ parameter decreases with NiO content in NiO/γ-Al 2 O 3 catalysts.

  6. Alergia ao leite de vaca: achados do ultrassom com Doppler colorido em neonatos com hematoquezia

    Directory of Open Access Journals (Sweden)

    Matias Epifanio

    2013-12-01

    Full Text Available OBJETIVO: o ultrassom (US tem sido uma importante ferramenta de diagnóstico para identificar várias causas de hemorragia gastrointestinal. Neonatos com alergia ao leite de vaca (ALV podem apresentar hematoquezia, e a confirmação do diagnóstico pode ser difícil. O objetivo deste estudo é descrever achados com ultrassom em escala de cinza e com Doppler colorido em pacientes com ALV. MÉTODOS: estudamos, retrospectivamente, 13 neonatos com ALV. Todos eles apresentaram hematoquezia severa e dor abdominal e foram submetidos a um estudo com US, com o diagnóstico de colite alérgica. O diagnóstico teve como base os achados clínicos, a recuperação após a dieta de exclusão do neonato ou da mãe, no caso de amamentação exclusiva, e o teste de provocação oral positivo. RESULTADOS: a idade média variou de um a seis meses (média = 3,53. Sete dos 13 neonatos (53,8% passaram novamente por ultrassonografia em escala de cinza e com Doppler colorido após a dieta de exclusão. Dentre eles, 12 dos 13 (92,3% mostraram anormalidades no US e no ultrassom com Doppler colorido (USDC no início. Os achados positivos que sugeriram colite foram paredes intestinais espessas e aumento na vascularização, principalmente no cólon descendente e sigmoide. Os resultados da colonoscopia e histopatológicos foram compatíveis com colite alérgica. Após uma mudança na dieta, os 13 neonatos se recuperaram e seus testes de provocação oral foram positivos. CONCLUSÃO: o US com Doppler pode ser muito útil para diagnosticar a colite secundária, como a ALV, e para excluir várias outras doenças abdominais que podem imitar essa doença.

  7. The impact of left ventricular preload reduction on cardiac pulsed doppler indices during hemodialysis and its relation to intra-dialysis hypotension: A pulsed doppler study

    International Nuclear Information System (INIS)

    Alarrayed, Sameer; Garadah Taysir Said; Alawdi, Abdulhai Ali

    2009-01-01

    Fluid status in the body plays an important role on left ventricular (LV) filling in patients with end-stage renal disease (ESRD) on regular hemodialysis (HD), and plays a role in intra-dialysis hemodynamic derangement. Fifty-two patients with ESRD on regular HD, including 34 males with a mean age of 45.5 +- 13 years (range 18-72 years), were studied. All patients underwent Echo-pulsed Doppler study before and immediately after a HD session. The Echo Doppler indices noted were: LV cavity dimension and wall thickness, LV ejection fraction (LVEF%), trans-mitral early diastolic filling velocity (E wave), atrial filling diastolic velocity (A wave), E/A ratio, Deceleration Time (DT) of E wave, Isovolumic relaxation time (IVRT), Aortic Velocity Integral (AVI) and Inferior Vena Cava Diameter (VCD) at expiration. Patients were divided into two groups according to the amount of net ultra filtrate loss after HD. Group I comprised of 25 patients with fluid loss of 2 liters. During the HD session, each patient was observed for the development of acute clinical events such as arterial hypotension (systolic BP less than 90 mmHg), chest pain and arrhythmias. There was a significant difference between the two groups in the mean values, pre- and post- HD, of reduction of E wave velocity (p < 0.01), the reduction of E/A ratio (p< 0.05), the increment in DT of E wave (p< 0.05), the reduction in AVI (p< 0.01) and the reduction of VCD (p< 0.05). There was no significant difference between the groups in the reduction of A wave velocity and the reduction of IVRT. Among the study patients, 11 (21%) developed systolic hypo-tension during HD. The pre-dialysis mean values of E/A ratio and DT of E wave in patients who developed hypotension compared to those who did not was 0.7 +- 0.2 vs 1.1 +- 0.2.1 (p< 0.001) and 246 +- 40 vs 224 +- 34 msec (p< 0.05), respectively. Our study suggests that preload reduction in patients with ESRD on regular HD is directly proportional to the reduction of left

  8. Transesophageal color Doppler evaluation of obstructive lesions using the new "Quasar" technology.

    Science.gov (United States)

    Fan, P; Nanda, N C; Gatewood, R P; Cape, E G; Yoganathan, A P

    1995-01-01

    Due to the unavoidable problem of aliasing, color flow signals from high blood flow velocities cannot be measured directly by conventional color Doppler. A new technology termed Quantitative Un-Aliased Speed Algorithm Recognition (Quasar) has been developed to overcome this limitation. Employing this technology, we used transesophageal color Doppler echocardiography to investigate whether the velocities detected by the Quasar would correlate with those obtained by continuous-wave Doppler both in vitro and in vivo. In the in vitro study, a 5.0 MHz transesophageal transducer of a Kontron Sigma 44 color Doppler flow system was used. Fourteen different peak velocities calculated and recorded by color Doppler-guided continuous-wave Doppler were randomly selected. In the clinical study, intraoperative transesophageal echocardiography was performed using the same transducer 18 adults (13 aortic valve stenosis, 2 aortic and 2 mitral stenosis, 2 hypertrophic obstructive cardiomyopathy and 1 mitral valve stenosis). Following each continuous-wave Doppler measurement, the Quasar was activated, and a small Quasar marker was placed in the brightest area of the color flow jet to obtain the maximum mean velocity readout. The maximum mean velocities measured by Quasar closely correlated with maximum peak velocities obtained by color flow guided continuous-wave Doppler in both in vitro (0.53 to 1.65 m/s, r = 0.99) and in vivo studies (1.50 to 6.01 m/s, r = 0.97). We conclude that the new Quasar technology can accurately measure high blood flow velocities during transesophageal color Doppler echocardiography. This technique has the potential of obviating the need for continuous-wave Doppler.

  9. DOPPLER SIGNATURES OF THE ATMOSPHERIC CIRCULATION ON HOT JUPITERS

    International Nuclear Information System (INIS)

    Showman, Adam P.; Lewis, Nikole K.; Fortney, Jonathan J.; Shabram, Megan

    2013-01-01

    The meteorology of hot Jupiters has been characterized primarily with thermal measurements, but recent observations suggest the possibility of directly detecting the winds by observing the Doppler shift of spectral lines seen during transit. Motivated by these observations, we show how Doppler measurements can place powerful constraints on the meteorology. We show that the atmospheric circulation—and Doppler signature—of hot Jupiters splits into two regimes. Under weak stellar insolation, the day-night thermal forcing generates fast zonal jet streams from the interaction of atmospheric waves with the mean flow. In this regime, air along the terminator (as seen during transit) flows toward Earth in some regions and away from Earth in others, leading to a Doppler signature exhibiting superposed blueshifted and redshifted components. Under intense stellar insolation, however, the strong thermal forcing damps these planetary-scale waves, inhibiting their ability to generate jets. Strong frictional drag likewise damps these waves and inhibits jet formation. As a result, this second regime exhibits a circulation dominated by high-altitude, day-to-night airflow, leading to a predominantly blueshifted Doppler signature during transit. We present state-of-the-art circulation models including non-gray radiative transfer to quantify this regime shift and the resulting Doppler signatures; these models suggest that cool planets like GJ 436b lie in the first regime, HD 189733b is transitional, while planets hotter than HD 209458b lie in the second regime. Moreover, we show how the amplitude of the Doppler shifts constrains the strength of frictional drag in the upper atmospheres of hot Jupiters. If due to winds, the ∼2 km s –1 blueshift inferred on HD 209458b may require drag time constants as short as 10 4 -10 6 s, possibly the result of Lorentz-force braking on this planet's hot dayside.

  10. Películas de ZnO piezoeléctricas depositadas por Spray Pirolisis US

    OpenAIRE

    Alcántara I., Salvador; Soto C, B Susana; Ortega J., L. Antonio; Cabañas T., Ruth L.; Pérez R., S. Jesús; Flores C., Gregorio

    2008-01-01

    El depósito de películas de ZnO con Spray Pirolisis es de mucho interés por la cantidad de aplicaciones de este material y por la simplicidad de la técnica mencionada. El uso del humidificador ultrasónico en lugar del spray neumático, permite obtener películas con mayor control y calidad. A las películas de ZnO obtenidas con esta técnica se les encontró efecto piezoeléctrico; en este trabajo se describe la técnica del depósito, la forma en que se compruebo el efecto piezoeléctrico y se presen...

  11. Trans-skull ultrasonic Doppler system aided by fuzzy logic

    Science.gov (United States)

    Hata, Yutaka; Nakamura, Masato; Yagi, Naomi; Ishikawa, Tomomoto

    2012-06-01

    This paper describes a trans-skull ultrasonic Doppler system for measuring the blood flow direction in brain under skull. In this system, we use an ultrasonic array probe with the center frequency of 1.0 MHz. The system determines the fuzzy degree of blood flow by Doppler Effect, thereby it locates blood vessel. This Doppler Effect is examined by the center of gravity shift of the frequency magnitudes. In in-vitro experiment, a cow bone was employed as the skull, and three silicon tubes were done as blood vessels, and bubble in water as blood. We received the ultrasonic waves through a protein, the skull and silicon tubes in order. In the system, fuzzy degrees are determined with respect to the Doppler shift, amplitude of the waves and attenuation of the tissues. The fuzzy degrees of bone and blood direction are calculated by them. The experimental results showed that the system successfully visualized the skull and flow direction, compared with the location and flow direction of the phantom. Thus, it detected the flow direction by Doppler Effect under skull, and automatically extracted the region of skull and blood vessel.

  12. Spectroscopic Doppler analysis for visible-light optical coherence tomography

    Science.gov (United States)

    Shu, Xiao; Liu, Wenzhong; Duan, Lian; Zhang, Hao F.

    2017-12-01

    Retinal oxygen metabolic rate can be effectively measured by visible-light optical coherence tomography (vis-OCT), which simultaneously quantifies oxygen saturation and blood flow rate in retinal vessels through spectroscopic analysis and Doppler measurement, respectively. Doppler OCT relates phase variation between sequential A-lines to the axial flow velocity of the scattering medium. The detectable phase shift is between -π and π due to its periodicity, which limits the maximum measurable unambiguous velocity without phase unwrapping. Using shorter wavelengths, vis-OCT is more vulnerable to phase ambiguity since flow induced phase variation is linearly related to the center wavenumber of the probing light. We eliminated the need for phase unwrapping using spectroscopic Doppler analysis. We split the whole vis-OCT spectrum into a series of narrow subbands and reconstructed vis-OCT images to extract corresponding Doppler phase shifts in all the subbands. Then, we quantified flow velocity by analyzing subband-dependent phase shift using linear regression. In the phantom experiment, we showed that spectroscopic Doppler analysis extended the measurable absolute phase shift range without conducting phase unwrapping. We also tested this method to quantify retinal blood flow in rodents in vivo.

  13. A study of doppler waveform using pulsatile flow model

    International Nuclear Information System (INIS)

    Chung, Hye Won; Chung, Myung Jin; Park, Jae Hyung; Chung, Jin Wook; Lee, Dong Hyuk; Min, Byoung Goo

    1997-01-01

    Through the construction of a pulsatile flow model using an artificial heart pump and stenosis to demonstrate triphasic Doppler waveform, which simulates in vivo conditions, and to evaluate the relationship between Doppler waveform and vascular compliance. The flow model was constructed using a flowmeter, rubber tube, glass tube with stenosis, and artificial heart pump. Doppler study was carried out at the prestenotic, poststenotic, and distal segments;compliance was changed by changing the length of the rubber tube. With increasing proximal compliance, Doppler waveforms show decreasing peak velocity of the first phase and slightly delayed acceleration time, but the waveform itself did not change significantly. Distal compliance influenced the second phase, and was important for the formation of pulsus tardus and parvus, which without poststenotic vascular compliance, did not develop. The peak velocity of the first phase was inversely proportional to proximal compliance, and those of the second and third phases were directly proportional to distal compliance. After constructing this pulsatile flow model, we were able to explain the relationship between vascular compliance and Doppler waveform, and also better understand the formation of pulsus tardus and parvus

  14. Response of a Doppler canceling system to plane gravitational waves

    International Nuclear Information System (INIS)

    Caporali, A.

    1982-01-01

    This paper discusses the interaction of long periodic gravitational waves with a three-link microwave system known as the Doppler canceling system. This system, which was developed for gravitational red-shift experiment, uses one-way and two-way Doppler information to construct the beat signal of two reference oscillators moving with respect to each other. The geometric-optics approximation is used to derive the frequency shift produced on a light signal propagating in a gravitational-wave space-time. The signature left on the Doppler-canceled beat by bursts and continuous gravitational waves is analyzed. A comparison is made between the response to gravitational waves of the Doppler canceling system and that of a (NASA) Doppler tracking system which employs two-way, round-trip radio waves. A threefold repetition of the gravitational wave form is found to be a common feature of the response functions of both systems. These two functions otherwise exhibit interesting differences

  15. Micro-Doppler Ambiguity Resolution Based on Short-Time Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Jing-bo Zhuang

    2015-01-01

    Full Text Available When using a long range radar (LRR to track a target with micromotion, the micro-Doppler embodied in the radar echoes may suffer from ambiguity problem. In this paper, we propose a novel method based on compressed sensing (CS to solve micro-Doppler ambiguity. According to the RIP requirement, a sparse probing pulse train with its transmitting time random is designed. After matched filtering, the slow-time echo signals of the micromotion target can be viewed as randomly sparse sampling of Doppler spectrum. Select several successive pulses to form a short-time window and the CS sensing matrix can be built according to the time stamps of these pulses. Then performing Orthogonal Matching Pursuit (OMP, the unambiguous micro-Doppler spectrum can be obtained. The proposed algorithm is verified using the echo signals generated according to the theoretical model and the signals with micro-Doppler signature produced using the commercial electromagnetic simulation software FEKO.

  16. Korea-China Joint R and D on Doppler Lidar Technology

    International Nuclear Information System (INIS)

    Cha, Hyung Ki; Kim, D. H.; Kwon, S. O.; Yang, K. H.; Song, I. K.

    2009-03-01

    Doppler lidar technology is to monitor atmospheric wind velocity by measuring the light scattering signals between a laser and aerosol particles or molecules existing in the atmosphere. When the particles (or molecules) in the atmosphere are moving by wind force, the frequency of backscattering light is shifted by doppler effect, so that the wind velocity profile can be obtained by measurement of the shifted frequencies. When the laser radiation is scanned in four different direction, three dimensional wind profiles are obtained. The Anhui Institute of Optics and Fine Mechanics under the China Academy of Sciences has developed and operated the doppler lidar system for long time. In this project we want to developed a new technologies adopted to the chinese doppler system and to test the updated In the process of collaboration between China and Korea research teams, we want to learn the state-of-art technology involved in the doppler lidar system

  17. The effectiveness of Doppler controlled hemorrhoidal artery ligation ...

    African Journals Online (AJOL)

    In this work, we discuss the preliminary results of the effectiveness of the hemorrhoidal artery ligation under control Doppler as a new technique for the treatment of hemorrhoids. We report the results of patients with hemorrhoids we have followed over a period of one year who were treated with HAL Doppler. The intra-and ...

  18. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji Young [Dept. of Radiology, Ewha Womans University School of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  19. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Directory of Open Access Journals (Sweden)

    Ji Young Hwang

    2017-04-01

    Full Text Available Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  20. Lorentz invariance and the rotor Doppler shift experiments

    International Nuclear Information System (INIS)

    Rodrigues Junior, W.A.; Tiomno, J.

    1984-01-01

    It is shown that 'Rotor Doppler shift Experiments' provide a way to distinguish Einstein's Special Relativity (SR) from Lorentz's Aether Theory (LAT). Misconceptions in previous papers involving the Doppler shift experiments are examined. The theoretical and experimental data available on rotor Doppler shift experiments are analysed. Two models of SR violating theories are used to predict the output of a recently proposed experiment by Torr and Kolen. The first one corresponds to (strict) LAT and the other to an extended form of LAT Contrary to the first, the second theory leads to results in agreement with the preliminary experimental data of Torr et al indicating a breakdown both of SR and strict LAT. (Author) [pt

  1. Lorentz invariance and the rotor Doppler shift experiments

    International Nuclear Information System (INIS)

    Rodrigues Junior, W.A.; Tiomno, J.

    1984-01-01

    It is shown that 'Rotor Doppler shift Experiments' provide a way to distinguish Einstein's Special Relativity (SR) from Lorentz's Aether Theory (LAT). Misconceptions in previous papers involving the Doppler shift experiments are examined. The theoretical and experimental data available on rotor Doppler shift experiments are analysed. Two models of SR violating theories are used to predict the output of a recently proposed experiment by Torr and Kolen. The first one corresponds to (strict) LAT and the other to an extended form of LAT. Contrary to the first, the second theory leads to results in agreement with the preliminary experimental data of Torr et al indicating a breakdown both of SR and strict LAT. (Author) [pt

  2. ISAR imaging using the instantaneous range instantaneous Doppler method

    CSIR Research Space (South Africa)

    Wazna, TM

    2015-10-01

    Full Text Available In Inverse Synthetic Aperture Radar (ISAR) imaging, the Range Instantaneous Doppler (RID) method is used to compensate for the nonuniform rotational motion of the target that degrades the Doppler resolution of the ISAR image. The Instantaneous Range...

  3. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  4. Three-dimensional power Doppler sonography in screening for carotid artery disease.

    Science.gov (United States)

    Keberle, M; Jenett, M; Beissert, M; Jahns, R; Haerten, R; Hahn, D

    2000-01-01

    Color Doppler sonography has gained considerable recognition as a noninvasive method to detect carotid artery disease and to assess the degree of carotid artery stenosis. However, results are highly operator-dependent and cannot be presented as survey images. The purpose of this study was to evaluate real-time 3-dimensional (3D) power Doppler sonography as a method for screening for atherosclerosis in the carotid arteries. We prospectively screened 75 patients for carotid artery disease using both conventional color Doppler sonography and 3D power Doppler sonography, and the results from the 2 modalities were compared. A total of 150 common carotid arteries, 150 internal carotid arteries, and 150 external carotid arteries were examined utilizing a 7.5-MHz linear-array transducer combined with tissue harmonic imaging. Color Doppler sonography detected 297 normal or atherosclerotic arteries without stenosis, 57 arteries with mild (1-49%) stenosis, 41 with moderate (50-69%) stenosis, 32 with severe (70-99%) stenosis, and 9 with occlusions. The degree of stenosis determined by color Doppler sonography correlated with that determined by 3D power Doppler sonography (r = 0.982-0.998). Moreover, there was a good correlation between the measurements for both the length of the lesion and its distance from the bulb as determined by the 3D volume surveys and by color Doppler sonography (r = 0.986). The interobserver variability rate was 3.7% +/- 0.5%. Generally, the acquisition and reconstruction of the 3D data took less than 5 minutes. 3D power Doppler sonography is easy to perform and is an accurate method in screening for atherosclerotic lesions of the carotid arteries. Moreover, it provides excellent 3D volume surveys that may be helpful in the planning of surgical treatment. Copyright 2000 John Wiley & Sons, Inc.

  5. Doppler electron velocimetry : notes on creating a practical tool.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.; Milster, Tom (University of Arizona)

    2008-11-01

    The Doppler electron velocimeter (DEV) has been shown to be theoretically possible. This report attempts to answer the next logical question: Is it a practical instrument? The answer hinges upon whether enough electrons are available to create a time-varying Doppler current to be measured by a detector with enough sensitivity and bandwidth. The answer to both of these questions is a qualified yes. A target Doppler frequency of 1 MHz was set as a minimum rate of interest. At this target a theoretical beam current signal-to-noise ratio of 25-to-1 is shown for existing electron holography equipment. A detector is also demonstrated with a bandwidth of 1-MHz at a current of 10 pA. Additionally, a Linnik-type interferometer that would increase the available beam current is shown that would offer a more flexible arrangement for Doppler electron measurements over the traditional biprism.

  6. Aplicação clínica da ultrassonografia craniana com Doppler em neonatos prematuros de muito baixo peso Clinical application of transcranial Doppler ultrasonography in premature, very-low-birth-weight neonates

    Directory of Open Access Journals (Sweden)

    Marta Lúcia Gabriel

    2010-08-01

    Full Text Available OBJETIVO: Analisar o valor do diagnóstico precoce de alterações hemodinâmicas em hemorragias e eventos hipóxico-isquêmicos pela avaliação de imagens e mensuração do índice de resistência por meio da ultrassonografia craniana com Doppler em neonatos prematuros de muito baixo peso. MATERIAIS E MÉTODOS: Cinquenta neonatos prematuros de muito baixo peso foram submetidos a ultrassonografia craniana com Doppler com a técnica transfontanela anterior e transtemporal sequenciais. RESULTADOS: Foram detectadas alterações cerebrais em 32% dos prematuros, sendo 22% com hemorragia intracraniana, 8% com leucomalácia periventricular e 2% com toxoplasmose. Dentre os 34 casos (68%, do total de neonatos, nos quais não foram detectadas lesões cerebrais pela ultrassonografia craniana, 18 (53% apresentaram alterações no índice de resistência. O índice de resistência variou conforme a época do exame. CONCLUSÃO: Existe correlação entre a presença de alterações na hemodinâmica cerebral e subsequente desenvolvimento de hemorragias e lesões hipóxico-isquêmicas, pela mensuração do índice de resistência. Alterações do índice de resistência, embora não preditoras de morte, estão relacionadas com a gravidade do quadro clínico em neonatos prematuros de muito baixo peso.OBJECTIVE: The present study was aimed at analyzing the value of the early diagnosis of hemodynamic changes in hemorrhages and hypoxic-ischemic events in premature, very-low-birth-weight neonates through the evaluation of images and resistance index measurement by means of transcranial Doppler ultrasonography. MATERIALS AND METHODS: Fifty premature, very-low-birth-weight neonates were submitted to transcranial Doppler ultrasonography with sequential transfontanellar and transtemporal techniques. RESULTS: Cerebral abnormalities were detected in 32% of the neonates (22% with intracranial hemorrhage, 8% with periventricular leukomalacia, and 2% with toxoplasmosis

  7. Designable ultra-smooth ultra-thin solid-electrolyte interphases of three alkali metal anodes.

    Science.gov (United States)

    Gu, Yu; Wang, Wei-Wei; Li, Yi-Juan; Wu, Qi-Hui; Tang, Shuai; Yan, Jia-Wei; Zheng, Ming-Sen; Wu, De-Yin; Fan, Chun-Hai; Hu, Wei-Qiang; Chen, Zhao-Bin; Fang, Yuan; Zhang, Qing-Hong; Dong, Quan-Feng; Mao, Bing-Wei

    2018-04-09

    Dendrite growth of alkali metal anodes limited their lifetime for charge/discharge cycling. Here, we report near-perfect anodes of lithium, sodium, and potassium metals achieved by electrochemical polishing, which removes microscopic defects and creates ultra-smooth ultra-thin solid-electrolyte interphase layers at metal surfaces for providing a homogeneous environment. Precise characterizations by AFM force probing with corroborative in-depth XPS profile analysis reveal that the ultra-smooth ultra-thin solid-electrolyte interphase can be designed to have alternating inorganic-rich and organic-rich/mixed multi-layered structure, which offers mechanical property of coupled rigidity and elasticity. The polished metal anodes exhibit significantly enhanced cycling stability, specifically the lithium anodes can cycle for over 200 times at a real current density of 2 mA cm -2 with 100% depth of discharge. Our work illustrates that an ultra-smooth ultra-thin solid-electrolyte interphase may be robust enough to suppress dendrite growth and thus serve as an initial layer for further improved protection of alkali metal anodes.

  8. Micro-Doppler classification of riders and riderless horses

    Science.gov (United States)

    Tahmoush, David

    2014-05-01

    Micro-range Micro-Doppler can be used to isolate particular parts of the radar signature, and in this case we demonstrate the differences in the signature between a walking horse versus a walking horse with a rider. Using micro-range micro-Doppler, we can distinguish the radar returns from the rider as separate from the radar returns of the horse.

  9. Color Doppler flow mapping of stenotic and regurgitant natural heart valves

    International Nuclear Information System (INIS)

    Nanda, N.C.

    1986-01-01

    Color Doppler echocardiography has found widest application in reliable detection and assessment of severity of both atrio-ventricular and semi-lunar valve incompetence. The authors believe both the sensitivity and specificity of color Doppler for the detection of mitral and aortic regurgitation is very high in patients with adequate acoustic windows. In 82 patients with proven mitral regurgitation studied, the best correlations with angiography were noted when the maximum or average regurgitant jet are obtained by color Doppler from three standard 2-D echo planes (parasternal long and short axis and apical four chamber view) and expressed as a percentage of the left atrial area were considered. The criteria the authors used for assessment of tricuspid and pulmonary valve incompetence are similar to those used for mitral and aortic valve incompetence, but the lack of a good ''gold'' standard has hampered validation. The color Doppler technique also supplements conventional Doppler in the assessment of severity of stenotic lesions by facilitating parallel alignment of the continuous wave Doppler cursor line with the stenotic jet for accurate recording of maximal velocities and pressure gradients. The authors have found this method especially useful in the assessment of aortic stenosis. In conclusion, color Doppler flow mapping combined with conventional echocardiography provides, for the first time, a comprehensive noninvasive assessement of the severity of regurgitant and stenotic lesions

  10. Comparison of the Diagnostic Performance of Power Doppler Ultrasound and a New Microvascular Doppler Ultrasound Technique (AngioPLUS) for Differentiating Benign and Malignant Breast Masses.

    Science.gov (United States)

    Jung, Hae Kyoung; Park, Ah Young; Ko, Kyung Hee; Koh, Jieun

    2018-03-12

    This study was performed to compare the diagnostic performance of power Doppler ultrasound (US) and a new microvascular Doppler US technique (AngioPLUS; SuperSonic Imagine, Aix-en-Provence, France) for differentiating benign and malignant breast masses. Power Doppler US and AngioPLUS findings were available in 124 breast masses with confirmed pathologic results (benign, 80 [64.5%]; malignant, 44 [35.5%]). The diagnostic performance of each tool was calculated to distinguish benign from malignant masses using a receiver operating characteristic curve analysis and compared. The area under the curve showed that AngioPLUS was superior to power Doppler US in differentiating benign from malignant breast masses, but the difference was not statistically significant. © 2018 by the American Institute of Ultrasound in Medicine.

  11. Acute Effects of Lateral Thigh Foam Rolling on Arterial Tissue Perfusion Determined by Spectral Doppler and Power Doppler Ultrasound.

    Science.gov (United States)

    Hotfiel, Thilo; Swoboda, Bernd; Krinner, Sebastian; Grim, Casper; Engelhardt, Martin; Uder, Michael; Heiss, Rafael U

    2017-04-01

    Hotfiel, T, Swoboda, B, Krinner, S, Grim, C, Engelhardt, M, Uder, M, and Heiss, R. Acute effects of lateral thigh foam rolling on arterial tissue perfusion determined by spectral Doppler and power Doppler ultrasound. J Strength Cond Res 31(4): 893-900, 2017-Foam rolling has been developed as a popular intervention in training and rehabilitation. However, evidence on its effects on the cellular and physiological level is lacking. The aim of this study was to assess the effect of foam rolling on arterial blood flow of the lateral thigh. Twenty-one healthy participants (age, 25 ± 2 years; height, 177 ± 9 cm; body weight, 74 ± 9 kg) were recruited from the medical and sports faculty. Arterial tissue perfusion was determined by spectral Doppler and power Doppler ultrasound, represented as peak flow (Vmax), time average velocity maximum (TAMx), time average velocity mean (TAMn), and resistive index (RI), and with semiquantitative grading that was assessed by 4 blindfolded investigators. Measurement values were assessed under resting conditions and twice after foam rolling exercises of the lateral thigh (0 and 30 minutes after intervention). The trochanteric region, mid portion, and distal tibial insertion of the lateral thigh were representative for data analysis. Arterial blood flow of the lateral thigh increased significantly after foam rolling exercises compared with baseline (p ≤ 0.05). We detected a relative increase in Vmax of 73.6% (0 minutes) and 52.7% (30 minutes) (p power Doppler scores at all portions revealed increased average grading of 1.96 after intervention and 2.04 after 30 minutes compared with 0.75 at baseline. Our results may contribute to the understanding of local physiological reactions to self-myofascial release.

  12. 21 CFR 892.1550 - Ultrasonic pulsed doppler imaging system.

    Science.gov (United States)

    2010-04-01

    ... system. (a) Identification. An ultrasonic pulsed doppler imaging system is a device that combines the... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic pulsed doppler imaging system. 892.1550... include signal analysis and display equipment, patient and equipment supports, component parts, and...

  13. Noise Studies of Externally Dispersed Interferometry for Doppler Velocimetry

    International Nuclear Information System (INIS)

    Erskine, D J; Edelstein, J; Lloyd, J; Muirhead, P

    2006-01-01

    Externally Dispersed Interferometry (EDI) is the series combination of a fixed-delay field-widened Michelson interferometer with a dispersive spectrograph. This combination boosts the spectrograph performance for both Doppler velocimetry and high resolution spectroscopy. The interferometer creates a periodic comb that multiplies against the input spectrum to create moire fringes, which are recorded in combination with the regular spectrum. Both regular and high-frequency spectral components can be recovered from the data--the moire component carries additional information that increases the signal to noise for velocimetry and spectroscopy. Here we present simulations and theoretical studies of the photon limited Doppler velocity noise in an EDI. We used a model spectrum of a 1600K temperature star. For several rotational blurring velocities 0, 7.5, 15 and 25 km/s we calculated the dimensionless Doppler quality index (Q) versus wavenumber v. This is the normalized RMS of the derivative of the spectrum and is proportional to the photon-limited Doppler signal to noise ratio

  14. Applications of Doppler in the first trimester

    International Nuclear Information System (INIS)

    Taylor, K.J.W.; Ramirez, B.; Grannum, P.

    1986-01-01

    Fifty patients have been studied by duplex Doppler US imaging in the first trimester. In normal gestations, luteal flow, characterized by a low pulsatility index (PI), can be seen in at least one ovary. Failure to detect luteal flow indicates a nonviable pregnancy. Six ectopic pregnancies demonstrated luteal flow and extrauterine heartbeat, detected by Doppler US. High PI values in the uterine artery are seen in the first trimester. Low PI values in the uterine arteries were found in patients with trophoblastic disease

  15. Christian Andreas Doppler--the man and his legacy.

    Science.gov (United States)

    Coman, I M

    2005-01-01

    Reminding the life and legacy of the Austrian Scientist who discovered the famous 'Doppler Effect'. C.A. Doppler was born the 29th of November 1803 in Salzburg. After studies in Linz and Vienna, he graduated in mathematics, became assistant at the University and later worked as a professor in Prague. Back to Vienna, he was appointed as professor at the Polytechnic School and --in 1850--as first director of the new Institute of Physics. C.A. Doppler did publish on magnetism, electricity, optics, and astronomy. He remains in the history of science due to the discovery presented (May 25, 1842) at the Royal Bohemian Society of Science entitled "On the colored light of the double stars and certain other stars of the heavens"; the paper described (applied to light) the shift of frequency which bears nowadays his name. The theory was later experimentally proven and--extended for any electromagnetic and acoustic waves--got myriads if applications in astronomy, physics, aviation, meteorology, and health science. Satomura in Japan (1955) published it's first ultrasound vascular application--with successive achievements in the next decades. Doppler ultrasonagraphy became the main noninvasive instrument for functional assesment of heart and vessels.

  16. Fetal Cardiac Doppler Signal Processing Techniques: Challenges and Future Research Directions

    Directory of Open Access Journals (Sweden)

    Saeed Abdulrahman Alnuaimi

    2017-12-01

    Full Text Available The fetal Doppler Ultrasound (DUS is commonly used for monitoring fetal heart rate and can also be used for identifying the event timings of fetal cardiac valve motions. In early-stage fetuses, the detected Doppler signal suffers from noise and signal loss due to the fetal movements and changing fetal location during the measurement procedure. The fetal cardiac intervals, which can be estimated by measuring the fetal cardiac event timings, are the most important markers of fetal development and well-being. To advance DUS-based fetal monitoring methods, several powerful and well-advanced signal processing and machine learning methods have recently been developed. This review provides an overview of the existing techniques used in fetal cardiac activity monitoring and a comprehensive survey on fetal cardiac Doppler signal processing frameworks. The review is structured with a focus on their shortcomings and advantages, which helps in understanding fetal Doppler cardiogram signal processing methods and the related Doppler signal analysis procedures by providing valuable clinical information. Finally, a set of recommendations are suggested for future research directions and the use of fetal cardiac Doppler signal analysis, processing, and modeling to address the underlying challenges.

  17. Doppler sonographic evaluation of ophthalmic arterial flow pattern in hypertensive patients

    International Nuclear Information System (INIS)

    Ryu, Dae Sik; Kim, Young Goo

    1994-01-01

    To compare the Doppler velocity waveform pattern of ophthalmic artery of hypertensive patients with that of normotensive subjects. Doppler velocity waveform was obtained from ophthalmic artery in 45 hypertensive patients and 60 normotensive subjects. Both hypertensives and normotensive subjects were classified according to age into those younger than and those older than 45 years. Doppler indices(pulsatility index(PI), resistance index(RI), the first systolic peak/the second systolic peak(S1/S2), the first systolic peak/diastolic peak(S1/D)) measured in hypertensive patients were compared with normotensive subjects. Among the various doppler indices, only S1/S2 showed significant difference(P < 0.05) between the hypertensive patients and normotensive subjects younger than 45 years. Doppler velocity waveform of hypertensive patients older than 45 years showed no significant difference from that of normotensive subjects with corresponding age. Doppler velocity waveform of ophthalmic artery in hypertensive patients younger than 45 years shows pattern with S2 higher than that of normotensive subjects. High S2 component(reflective-wave) may represent increased vascular impedance due to vasococonstriction of retinal arterioles in hypertensive patients

  18. Magnetic angioresonance of the carotid artery: correlation with color Doppler ultrasound

    International Nuclear Information System (INIS)

    Cotilla, J.; Miralles, M.; Cairols, M.C.; Dolz, J.L.; Vilanova, J.C.; Capdevila, A.

    1998-01-01

    To determine the value of magnetic angioresonance (MAR) in grading carotid stenosis, comparing it with color Doppler and intraarterial digital subtraction angiography (IADSA). A comparative study using color Doppler and MAR was carried out in 84 patients with coratid lesions. Fifty-two of the patients underwent angiographic study as well. The comparison of MAR versus arteriography in discriminating stenosis of more than 70%, expressed in terms of sensitivity specificity, overall precision and the kappa concordance index, gave values of 87.2, 90.8, 89.4 and 0.78%, respectively. When MAR was compared with color Doppler, the results were 86.8, 85.9, 86.3 and 0.72%, respectively. The results of the comparison between color Doppler and arteriography were 82.2, 86.2, 84.6 and 0.68%, respectively. The better correlation of MAR, as compares with angiography and color Doppler, with the grade of carotid stenosis indicates the high degree of reliability. The better correlation of MAR, as compares with angiography and color Doppler, with the grade of carotid stenosis indicates the high degree of reliability of this imaging technique. (Author) 29 refs

  19. Use of TRIGA-pulsed irradiations for high-temperature Doppler measurements

    Energy Technology Data Exchange (ETDEWEB)

    Foell, W K; Cashwell, R J; Bhattacharyya, S K [Argonne National Laboratory, Argonne, IL (United States); Russell, G J [Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1974-07-01

    Conventional activation and reactivity measurements of the nuclear Doppler Effect have been limited to temperatures of about 2000{sup o}K because of problems with furnace equipment. There is a need for Doppler data at higher temperatures for design of reactors and analysis of reactor accidents. To fill this need, a novel technique using pulsed-mode operation of a TRIGA reactor has been developed at the University of Wisconsin. This new method, the Pulsed Activation Doppler (PAD) technique, has been used successfully for high temperature Doppler measurements of UO{sub 2} fuel pellets. In the PAD technique, UO{sub 2} test pellets were doped with varying amounts of U-235, with fissile enrichments varying from 0.22% to 12% by weight. The pellets were encapsulated in individual irradiation cells and electrically preheated to predetermined temperatures. Pyrofoam-graphite heaters were used to give preheat temperatures of up to 1720 deg. K. The cells were then positioned in the University of Wisconsin TRIGA reactor core and pulse-irradiated. During the rapid irradiation, adiabatic fission energy deposition occurred in the pellets and very high temperatures (over 3115 deg, K) were attained. Corresponding resonance neutron captures occurred at the elevated temperatures. The Doppler Ratio was deduced from the gamma activities of the Np-239 in the heated and unheated reference pellets. UO{sub 2} pellets of two nominal diameters, 210 mils (a surface-to-mass ratio, s/m = 1.1 cm{sup 2} /gm) and 360 mils (s/m = 0.63 cm{sup 2}/gm), were used for the experiments. For the 210 mil diameter pellets there was very good agreement between experimental results and Doppler ratios predicted both from extrapolations of the Hellstrand low-temperature resonance integral correlations and from GAROL calculations. Significantly, the agreement was good even for those pellets which experienced extensive melting. For the 360 mil diameter pellets the theoretical predictions were 10-15% lower than

  20. Doppler ultrasound scan during normal gestation: umbilical circulation

    International Nuclear Information System (INIS)

    Ruiz, T.; Sabate, J.; Martinez-Benavides, M. M.; Sanchez-Ramos, J.

    2002-01-01

    To determine normal umbilical circulation patterns by means of Doppler ultrasound scan in a healthy gestating population without risk factors and with normal perinatal results, and to evaluate any occurring modifications relative to gestational age by obtaining records kept during pregnancy. One hundred and sixteen pregnant women carrying a single fetus have been studied. These women had no risk factors, with both clinical and analytical controls, as well as ultrasound scans, all being normal. There were performed a total of 193 Doppler ultrasound scans between weeks 15 and 41 of gestation, with blood-flow analysis in the arteries and vein of the umbilical cord. The obtained information was correlated with parameters that evaluate fetal well-being (fetal monitoring and/or oxytocin test) and perinatal result (delivery type, birth weight, Apgar score). Statistical analysis was performed with the programs SPSS 6.0.1 for Windows and EPIINFO 6.0.4. With pulsed Doppler, the umbilical artery in all cases demonstrated a biphasic morphology with systolic and diastolic components and without retrograde blood flow. As the gestation period increased, there was observed a progressive decrease in resistance along with an increase in blood-flow velocity during the diastolic phase. The Doppler ultrasound scan is a non-invasive method that permits the hemodynamic study of umbilical blood circulation. A knowledge of normal blood-flow signal morphology, as well as of the normal values for Doppler indices in relation to gestational age would permit us to utilize this method in high-risk pregnancies. (Author) 30 refs

  1. Dispersed single-phase-step Michelson interferometer for Doppler imaging using sunlight.

    Science.gov (United States)

    Wan, Xiaoke; Ge, Jian

    2012-09-15

    A Michelson interferometer is dispersed with a fiber array-fed spectrograph, providing 59 Doppler sensing channels using sunlight in the 510-570 nm wavelength region. The interferometer operates at a single-phase-step mode, which is particularly advantageous in multiplexing and data processing compared to the phase-stepping mode of other interferometer spectrometer instruments. Spectral templates are prepared using a standard solar spectrum and simulated interferometer modulations, such that the correlation function with a measured 1D spectrum determines the Doppler shift. Doppler imaging of a rotating cylinder is demonstrated. The average Doppler sensitivity is ~12 m/s, with some channels reaching ~5 m/s.

  2. An elementary approach to the gravitational Doppler shift

    International Nuclear Information System (INIS)

    Wörner, C H; Rojas, Roberto

    2017-01-01

    In college physics courses, treatment of the Doppler effect is usually done far from the first introduction to kinematics. This paper aims to apply a graphical treatment to describe the gravitational redshift, by considering the Doppler effect in two accelerated reference frames and exercising the equivalence principle. This approach seems appropriate to discuss with beginner students and could serve to enrich the didactic processes. (paper)

  3. Ultrasound and Doppler examination capabilities in adult portal hypertension type definition

    Directory of Open Access Journals (Sweden)

    N. V. Tumanskaya

    2015-08-01

    Full Text Available Early portal hypertension type diagnostics is an ultimate factor concerning kind and tactics of treatment. Aim. To objectify ultrasound examination capabilities, portal hemodynamics were studied in 97 patients using impulse and color doppler. Methods and results. It was ascertained that impulse and color doppler examination allows to visualize portal vein and its branches’ structural abnormalities, define subhepatic and intrahepatic types of portal hypertension, find thrombosis and characterize its stages. In cirrhosis patients with portal hypertension, homogenous doppler signal was received from the portal vessels lumen, while signs of intraluminar pathology were seen in the case of thrombosis of portal vein. Conclusion. This means that ultrasound examination of portal vein and its branches with impulse and color doppler is informative, non invasive method, which helps to define stages of portal hypertension. Doppler ultrasonography doesn’t have negative effect of ionizing radiation and can be used for the repeated research in the dynamics of disease.

  4. Superimposed noninterfering probes to extend the capabilities of phase Doppler anemometry.

    Science.gov (United States)

    Onofri, Fabrice; Lenoble, Anne; Radev, Stefan

    2002-06-20

    We propose using multiple superimposed noninterfering probes (SNIPs) of the same wavelength but different beam angles to extend the capabilities of phase Doppler anemometry. When a particle is moving in a SNIP the Doppler signals that are produced exhibit multiple Doppler frequencies and phase shifts. The resolution of the measurements of particle size (i.e., by fringe spacing and Doppler frequency) increases with beam angle. Then, with the solution proposed, even with only two detectors several measurements of size can be obtained for the same particle with increasing resolution if we consider higher frequencies in the signal. Several optical solutions to produce SNIPs as well as a signal-processing algorithm to treat the multiple-frequency Doppler signals are proposed. Experimental validations of the sizing of spherical and cylindrical particles demonstrate the applicability of this technique for particle measurement. We believe that this new technique can be of great interest when high resolution of size, velocity, and even refractive index is required.

  5. Images generated by ultra-sound; Imagenes generadas por ultrasonido

    Energy Technology Data Exchange (ETDEWEB)

    Godinez, Valery Francisco; Marcial, Miguel Angel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-01-01

    inspeccion requirio del analisis de imagenes ultrasonicas de las soldaduras de dos muestras de bastones; dichas imagenes se generaron mediante un barrido ultrasonico tipo C (C-scan) usando un sistema integrado en el Laboratorio de Pruebas no Destructivas de la Unidad de Sistemas de Combustion del Instituto de Investigaciones Electricas (IIE). El analisis permitio establecer la configuracion adecuada del equipo a utilizar en la inspeccion en sitio, los procedimientos de calibracion del mismo y los criterios de aceptacion/rechazo de las soldaduras a inspeccionar. Asimismo, se presenta una correlacion entre los valores de los coeficientes de reflexion ultrasonicos medidos en las soldaduras y los valores teoricos para la adherencia en la interfaz solido-solido predichos por un modelo simple de interfaz imperfecta. Estos resultados son un primer paso en la caracterizacion cuantitativa de uniones solido-solido, que aunado a futuros desarrollos tendria un impacto tecnologico inmediato en la determinacion del estado de soldaduras por friccion, soldaduras con aporte de metal fundido y grado de adherencia de recubrimientos sobre estructuras expuestas a condiciones que inducen corrosion.

  6. Correlation between Spectral Index and Doppler Factor for a ...

    Indian Academy of Sciences (India)

    Abstract. Relativistic beaming effect is important for blazars. In a very recent work, γ-ray Doppler factors were calculated for a sample of Fermi blazars (Fan et al. 2013). In this work, we investigated the correlation between the Doppler factor and the effective spectral index, αOX, and found an anticorrelation between them.

  7. Technical Note: A new phantom design for routine testing of Doppler ultrasound.

    Science.gov (United States)

    Grice, J V; Pickens, D R; Price, R R

    2016-07-01

    The objective of this project is to demonstrate the principle and operation for a simple, inexpensive, and highly portable Doppler ultrasound quality assurance (QA) phantom intended for routine QA testing. A prototype phantom has been designed, fabricated, and evaluated. The phantom described here is powered by gravity alone, requires no external equipment for operation, and produces a stable fluid velocity useful for quality assurance. Many commercially available Doppler ultrasound testing systems can suffer from issues such as a lengthy setup, prohibitive cost, nonportable size, or difficulty in use. This new phantom design aims to address some of these problems and create a phantom appropriate for assessing Doppler ultrasound stability. The phantom was fabricated using a 3D printer. The basic design of the phantom is to provide gravity-powered flow of a Doppler fluid between two reservoirs. The printed components were connected with latex tubing and then seated in a tissue mimicking gel. Spectral Doppler waveforms were sampled to evaluate variations in the data, and the phantom was evaluated using high frame rate video to find an alternate measure of mean fluid velocity flowing in the phantom. The current system design maintains stable flow from one reservoir to the other for approximately 7 s. Color Doppler imaging of the phantom was found to be qualitatively consistent with laminar flow. Using pulsed spectral Doppler, the average fluid velocity from a sample volume approximately centered in the synthetic vessel was measured to be 56 cm/s with a standard deviation of 3.2 cm/s across 118 measurements. An independent measure of the average fluid velocity was measured to be 51.9 cm/s with a standard deviation of 0.7 cm/s over 4 measurements. The developed phantom provides stable fluid flow useful for frequent clinical Doppler ultrasound testing and attempts to address several obstacles facing Doppler phantom testing. Such an ultrasound phantom can make routine

  8. Application of coincidence Doppler-broadening spectroscopy to different carbon phases

    International Nuclear Information System (INIS)

    Ito, Y.; Djourelov, N.; Suzuki, T.; Kondo, K.; Ito, Y.; Shantarovich, V.; Onoe, J.

    2004-01-01

    Coincidence Doppler-broadening spectroscopy was applied to C60 and C70 fullerenes and other carbon phases, such as nanotubes and graphites. Remarkable differences were observed in the Doppler-broadening of the positron annihilation γ-rays in these materials, which reflect the different densities distribution of the momentum for electrons annihilated with positrons. This would be caused by the different composition of the π and σ electrons in annihilation with positrons. This result shows the sensitivity of the coincidence Doppler-broadening method to determine the density distribution of electrons sampled by positrons. (orig.)

  9. Assessment of ureterovesical jet dynamics in obstructed ureter by urinary stone with color Doppler and duplex Doppler examinations.

    Science.gov (United States)

    Jandaghi, Ali Babaei; Falahatkar, Siavash; Alizadeh, Ahmad; Kanafi, Alireza Rajabzadeh; Pourghorban, Ramin; Shekarchi, Babak; Zirak, Amin Keshavarz; Esmaeili, Samaneh

    2013-04-01

    This study was designed to evaluate ureterovesical jet dynamics in obstructed ureter and to compare it with those of contralateral unobstructed side. Forty-six patients with diagnosis of ureteral stone, based on imaging findings in computed tomography were enrolled in this study. The gray-scale ultrasound exam from both kidneys and urinary bladder was performed. Then, ureterovesical jet characteristics including ureteral jet frequency, duration and peak velocity were assessed by color Doppler and duplex Doppler studies in both obstructed and unobstructed ureters by a radiologist, 15-30 min after oral hydration with 750-1,000 mL of water. When compared with contralateral normal side, the ureterovesical jet in obstructed ureter showed less frequency (0.59 vs. 3.04 jets/min; P < 0.05), shorter duration (1.24 vs. 5.26 s; P < 0.05) and lower peak velocity (5.41 vs. 32.09 cm/s; P < 0.05). The cut-off points of 1.5 jets/min, 2.5 s and 19.5 cm/s for difference of ureteral jet frequency, duration and peak velocity between obstructed and contralateral normal ureters yielded sensitivities of 97.8, 95.6 and 100 % and specificities of 87, 87.9 and 97.8 %, respectively for diagnosis of ureteral obstruction. Given the safety of Doppler study and significant differences in flow dynamics of obstructed versus unobstructed ureters, our findings demonstrated the utility of Doppler ultrasound examination as a useful adjunct to gray-scale ultrasound by improving the accuracy of ultrasound exam in diagnosis of ureteral obstruction.

  10. Comparative analysis of pulsed doppler ultrasonography of portal vein vs indirect photography

    International Nuclear Information System (INIS)

    Chang, Jae Chun; Kwon, Huck Po; Hwang, Mi Soo; Kim, Sun Youn; Park, Bok Hwan; Lee, Hyun Ju; Kim, Hong Jin

    1990-01-01

    There are some limitation of interpretation in indirect photography via superior mesenteric artery. In order to supplement and predict indirect photography, we compared indirect photographic findings with pulsed doppler flowmetry in 38 hepatobiliary patients, and the results were as follow: 1. In case of normal main portal vein(MPV) filling, Pulsed Doppler always showed antegrade, continuous parabolic wave form and cases of abnormal MPV filling, showed unusual wave form and flow direction. 2. In normal filling case of proximal right portal vein, Pulsed Doppler almost showed normal continuous parabolic wave form but in normal filling cases of proximal left portal vein, occasionally showed undulating wave form. 3. In each side proximal portal vein abnormal filling case, we could observe abnormal doppler wave form and could obtain additional information using doppler wave form. 4. Mean portal flow velocity was significantly increased in higher photography grade(p=0.01) and congestion index was significantly decreased in higher photography grade(p=0.01). 5. We concluded that doppler ultrasonography could supplement incomplete indirect photography

  11. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee [Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2009-12-15

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  12. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    International Nuclear Information System (INIS)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee; Kim, Sam Soo

    2009-01-01

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  13. Moving Target Detection With Compact Laser Doppler Radar

    Science.gov (United States)

    Sepp, G.; Breining, A.; Eisfeld, W.; Knopp, R.; Lill, E.; Wagner, D.

    1989-12-01

    This paper describes an experimental integrated optronic system for detection and tracking of moving objects. The system is based on a CO2 waveguide laser Doppler ra-dar with homodyne receiver and galvanometer mirror beam scanner. A "hot spot" seeker consisting of a thermal imager with image processor transmits the coordinates of IR-emitting, i.e. potentially powered, objects to the laser radar scanner. The scanner addresses these "hot" locations operating in a large field-of-view (FOV) random ac-cess mode. Hot spots exhibiting a Doppler shifted laser signal are indicated in the thermal image by velocity-to-colour encoded markers. After switching to a small FOV scanning mode, the laser Doppler radar is used to track fast moving objects. Labora-tory and field experiments with moving objects including rotating discs, automobiles and missiles are described.

  14. Three-dimensional laser cooling at the Doppler limit

    Science.gov (United States)

    Chang, R.; Hoendervanger, A. L.; Bouton, Q.; Fang, Y.; Klafka, T.; Audo, K.; Aspect, A.; Westbrook, C. I.; Clément, D.

    2014-12-01

    Many predictions of Doppler-cooling theory of two-level atoms have never been verified in a three-dimensional geometry, including the celebrated minimum achievable temperature ℏ Γ /2 kB , where Γ is the transition linewidth. Here we show that, despite their degenerate level structure, we can use helium-4 atoms to achieve a situation in which these predictions can be verified. We make measurements of atomic temperatures, magneto-optical trap sizes, and the sensitivity of optical molasses to a power imbalance in the laser beams, finding excellent agreement with Doppler theory. We show that the special properties of helium, particularly its small mass and narrow transition linewidth, prevent effective sub-Doppler cooling with red-detuned optical molasses. This discussion can be generalized to identify when a given species is likely to be subject to the same limitation.

  15. Color doppler ultrasound diagonosis in cesarean scar pregnancy

    International Nuclear Information System (INIS)

    Chen Shanshan; Xia Fei; Shen Zongji; Xu Jianyin; Gu Xinxian

    2010-01-01

    Objective: To study the sonographic characteristics of cesarean scar pregnancy(CSP), and the value of color Doppler in the diagnosis of CSP. Methods: Twelve cases of CSP were all confirmed by transabdominal and transvaginal ultrasound. Results: The ultrasonogram of CSP could be divided into gestational sac type and mixed mass type. Conclusion: Color Doppler can give guidance to the early diagnosis, treatment and following-up of CSP because of the sonographic specifity of CSP. (authors)

  16. Tracking Architecture Based on Dual-Filter with State Feedback and Its Application in Ultra-Tight GPS/INS Integration.

    Science.gov (United States)

    Zhang, Xi; Miao, Lingjuan; Shao, Haijun

    2016-05-02

    If a Kalman Filter (KF) is applied to Global Positioning System (GPS) baseband signal preprocessing, the estimates of signal phase and frequency can have low variance, even in highly dynamic situations. This paper presents a novel preprocessing scheme based on a dual-filter structure. Compared with the traditional model utilizing a single KF, this structure avoids carrier tracking being subjected to code tracking errors. Meanwhile, as the loop filters are completely removed, state feedback values are adopted to generate local carrier and code. Although local carrier frequency has a wide fluctuation, the accuracy of Doppler shift estimation is improved. In the ultra-tight GPS/Inertial Navigation System (INS) integration, the carrier frequency derived from the external navigation information is not viewed as the local carrier frequency directly. That facilitates retaining the design principle of state feedback. However, under harsh conditions, the GPS outputs may still bear large errors which can destroy the estimation of INS errors. Thus, an innovative integrated navigation filter is constructed by modeling the non-negligible errors in the estimated Doppler shifts, to ensure INS is properly calibrated. Finally, field test and semi-physical simulation based on telemetered missile trajectory validate the effectiveness of methods proposed in this paper.

  17. Laser doppler perfusion imaging

    International Nuclear Information System (INIS)

    Waardell, K.

    1992-01-01

    Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

  18. Análisis experimental de un motor ultrasónico de elevado par

    Directory of Open Access Journals (Sweden)

    Mateo Prous, C.

    1999-12-01

    Full Text Available Ultrasonic engines are useful in several applications due to low weight, small size, good position and speed regulation, and high torque. Nowadays there are only low and medium torque engines. We are working on high torque ultrasonic engines, which can be used as power actuators. Among all possible configurations, we are dealing with a standard piezoelectric ceramic excited one, which works in the no linear zone and resonant mode. A static, modal, harmonic and transitory finite elements analysis is being carrying on. The final goal is to obtain all components design criteria in order to optimise the obtained result. The finite element analysis and motor functioning are explained, showing two prototype results, and describing the improvements of the second one and his reason.

    Los motores ultrasónicos son útiles en diversas aplicaciones debido a su poco peso, pequeñas dimensiones, buena regulación de la posición y velocidad, y elevado par. Hoy en día tan sólo existen motores que desarrollan un par bajo o medio. En esta línea, estamos trabajando en motores ultrasónicos de par elevado, que pueden ser utilizados como actuadores de potencia. Entre todas las configuraciones inicialmente propuestas, se está analizando en detalle una que es excitada por cerámica piezoeléctrica estándar, que trabaja en la zona no lineal y en modo resonante. El análisis, realizado por elementos finitos, abarca el estático y el modal, el armónico y el transitorio. En este artículo se describen el funcionamiento del motor y su análisis por elementos finitos, mostrando los resultados experimentales de dos prototipos, y describiendo las mejoras que aporta el segundo debidamente justificadas.

  19. [The value of Doppler sonography in the detection of fetal hypoxia].

    Science.gov (United States)

    Aranyosi, János; Zatik, János; Juhász, A Gábor; Fülesdi, Béla; Major, Tamás

    2002-10-27

    Doppler ultrasound has become a part of routine antenatal fetal surveillance during the past two decades. It provides insight into the utero-placental and fetal arterial, venous circulation non-invasively. Doppler examination has a key role in the detection of hypoxic risk since abnormal blood flow patterns can be demonstrated before the clinical manifestation of fetal disorder. Doppler velocimetry facilitates judgment in the diagnosis, monitoring fetal well-being during pregnancy and labor, scheduling antenatal tests and timing delivery. Authors review the effects of chronic and acute hypoxia on fetal hemodynamics. On the basis of the present knowledge and experience a brief summary is given about the role of Doppler velocimetry in the early detection of hypoxic fetal jeopardy during pregnancy and labor.

  20. Doppler Centroid Estimation for Airborne SAR Supported by POS and DEM

    Directory of Open Access Journals (Sweden)

    CHENG Chunquan

    2015-05-01

    Full Text Available It is difficult to estimate the Doppler frequency and modulating rate for airborne SAR by using traditional vector method due to instable flight and complex terrain. In this paper, it is qualitatively analyzed that the impacts of POS, DEM and their errors on airborne SAR Doppler parameters. Then an innovative vector method is presented based on the range-coplanarity equation to estimate the Doppler centroid taking the POS and DEM as auxiliary data. The effectiveness of the proposed method is validated and analyzed via the simulation experiments. The theoretical analysis and experimental results show that the method can be used to estimate the Doppler centroid with high accuracy even in the cases of high relief, instable flight, and large squint SAR.

  1. Doppler velocity measurements from large and small arteries of mice

    Science.gov (United States)

    Reddy, Anilkumar K.; Madala, Sridhar; Entman, Mark L.; Michael, Lloyd H.; Taffet, George E.

    2011-01-01

    With the growth of genetic engineering, mice have become increasingly common as models of human diseases, and this has stimulated the development of techniques to assess the murine cardiovascular system. Our group has developed nonimaging and dedicated Doppler techniques for measuring blood velocity in the large and small peripheral arteries of anesthetized mice. We translated technology originally designed for human vessels for use in smaller mouse vessels at higher heart rates by using higher ultrasonic frequencies, smaller transducers, and higher-speed signal processing. With these methods one can measure cardiac filling and ejection velocities, velocity pulse arrival times for determining pulse wave velocity, peripheral blood velocity and vessel wall motion waveforms, jet velocities for the calculation of the pressure drop across stenoses, and left main coronary velocity for the estimation of coronary flow reserve. These noninvasive methods are convenient and easy to apply, but care must be taken in interpreting measurements due to Doppler sample volume size and angle of incidence. Doppler methods have been used to characterize and evaluate numerous cardiovascular phenotypes in mice and have been particularly useful in evaluating the cardiac and vascular remodeling that occur following transverse aortic constriction. Although duplex ultrasonic echo-Doppler instruments are being applied to mice, dedicated Doppler systems are more suitable for some applications. The magnitudes and waveforms of blood velocities from both cardiac and peripheral sites are similar in mice and humans, such that much of what is learned using Doppler technology in mice may be translated back to humans. PMID:21572013

  2. Pulsed-wave transmitral Doppler do not diagnose moderate acute rejection after heart transplantation

    NARCIS (Netherlands)

    Mannaerts, H. F.; Simoons, M. L.; Balk, A. H.; Tijssen, J.; van der Borden, S. G.; Zondervan, P. E.; Mochtar, B.; Weimar, W.; Roelandt, J. R.

    1993-01-01

    The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously

  3. PULSED-WAVE TRANSMITRAL DOPPLER DO NOT DIAGNOSE MODERATE ACUTE REJECTION AFTER HEART-TRANSPLANTATION

    NARCIS (Netherlands)

    MANNAERTS, HF; SIMOONS, ML; BALK, AH; TIJSSEN, J; VANDERBORDEN, SG; ZONDERVAN, PE; MOCHTAR, B; WEIMAR, W; ROELANDT, [No Value

    1993-01-01

    The value of pulsed-wave transmitral Doppler for the diagnosis of moderate acute rejection was examined in a total of 347 Doppler recordings obtained in 32 consecutive cardiac allograft recipients. Serial Doppler examinations (median, 11 per patient; range, 1 to 23) were performed simultaneously

  4. Compressive sensing for high resolution profiles with enhanced Doppler performance

    NARCIS (Netherlands)

    Anitori, L.; Hoogeboom, P.; Chevalier, F. Le; Otten, M.P.G.

    2012-01-01

    In this paper we demonstrate how Compressive Sensing (CS) can be used in pulse-Doppler radars to improve the Doppler performance while preserving range resolution. We investigate here two types of stepped frequency waveforms, the coherent frequency bursts and successive frequency ramps, which can be

  5. Physiology and Pathophysiology in Ultra-Marathon Running

    Directory of Open Access Journals (Sweden)

    Beat Knechtle

    2018-06-01

    Full Text Available In this overview, we summarize the findings of the literature with regards to physiology and pathophysiology of ultra-marathon running. The number of ultra-marathon races and the number of official finishers considerably increased in the last decades especially due to the increased number of female and age-group runners. A typical ultra-marathoner is male, married, well-educated, and ~45 years old. Female ultra-marathoners account for ~20% of the total number of finishers. Ultra-marathoners are older and have a larger weekly training volume, but run more slowly during training compared to marathoners. Previous experience (e.g., number of finishes in ultra-marathon races and personal best marathon time is the most important predictor variable for a successful ultra-marathon performance followed by specific anthropometric (e.g., low body mass index, BMI, and low body fat and training (e.g., high volume and running speed during training characteristics. Women are slower than men, but the sex difference in performance decreased in recent years to ~10–20% depending upon the length of the ultra-marathon. The fastest ultra-marathon race times are generally achieved at the age of 35–45 years or older for both women and men, and the age of peak performance increases with increasing race distance or duration. An ultra-marathon leads to an energy deficit resulting in a reduction of both body fat and skeletal muscle mass. An ultra-marathon in combination with other risk factors, such as extreme weather conditions (either heat or cold or the country where the race is held, can lead to exercise-associated hyponatremia. An ultra-marathon can also lead to changes in biomarkers indicating a pathological process in specific organs or organ systems such as skeletal muscles, heart, liver, kidney, immune and endocrine system. These changes are usually temporary, depending on intensity and duration of the performance, and usually normalize after the race. In

  6. Study on Zero-Doppler Centroid Control for GEO SAR Ground Observation

    Directory of Open Access Journals (Sweden)

    Yicheng Jiang

    2014-01-01

    Full Text Available In geosynchronous Earth orbit SAR (GEO SAR, Doppler centroid compensation is a key step for imaging process, which could be performed by the attitude steering of a satellite platform. However, this zero-Doppler centroid control method does not work well when the look angle of radar is out of an expected range. This paper primarily analyzes the Doppler properties of GEO SAR in the Earth rectangular coordinate. Then, according to the actual conditions of the GEO SAR ground observation, the effective range is presented by the minimum and maximum possible look angles which are directly related to the orbital parameters. Based on the vector analysis, a new approach for zero-Doppler centroid control in GEO SAR, performing the attitude steering by a combination of pitch and roll rotation, is put forward. This approach, considering the Earth’s rotation and elliptical orbit effects, can accurately reduce the residual Doppler centroid. All the simulation results verify the correctness of the range of look angle and the proposed steering method.

  7. Precise Doppler shift compensation in the hipposiderid bat, Hipposideros armiger.

    Science.gov (United States)

    Schoeppler, Diana; Schnitzler, Hans-Ulrich; Denzinger, Annette

    2018-03-15

    Bats of the Rhinolophidae and Hipposideridae families, and Pteronotus parnellii, compensate for Doppler shifts generated by their own flight movement. They adjust their call frequency such that the frequency of echoes coming from ahead fall in a specialized frequency range of the hearing system, the auditory fovea, to evaluate amplitude and frequency modulations in echoes from fluttering prey. Some studies in hipposiderids have suggested a less sophisticated or incomplete Doppler shift compensation. To investigate the precision of Doppler shift compensation in Hipposideros armiger, we recorded the echolocation and flight behaviour of bats flying to a grid, reconstructed the flight path, measured the flight speed, calculated the echo frequency, and compared it with the resting frequency prior to each flight. Within each flight, the average echo frequency was kept constant with a standard deviation of 110 Hz, independent of the flight speed. The resting and reference frequency were coupled with an offset of 80 Hz; however, they varied slightly from flight to flight. The precision of Doppler shift compensation and the offset were similar to that seen in Rhinolophidae and P. parnellii. The described frequency variations may explain why it has been assumed that Doppler shift compensation in hipposiderids is incomplete.

  8. Renal Power Doppler Ultrasonographic Evaluation of Children With Acute Pyelonephritis

    Directory of Open Access Journals (Sweden)

    Ali Pahlusi

    2011-10-01

    Full Text Available Urinary tract infections are common in children. The available gold standard method for diagnosis, Tc-99m dimercaptosuccinic acid scan is expensive and exposes patients to considerable amount of radiation. This study was performed to compare and assess the efficacy of Power Doppler Ultrasound versus Tc-99m DMSA scan for diagnosis of acute pyelonephritis. A quasi experimental study was conducted on 34 children with mean age of 2.82.7 years who were hospitalized with their first episode of febrile urinary tract infection. All children were evaluated in the first 3 days of admission by Doppler Ultrasound and Tc-99m DMSA scan. Patients with congenital structural anomalies were excluded. Each kidney was divided into three zones. The comparison between efficacy of Doppler Ultrasound and DMSA scan was carried out based on number of patients and on classified renal units. Based on the number of patients enrolled; the sensitivity, specificity, positive and negative predictive values and accuracy of Doppler Ultrasound were 89%, 53%, 70%, 80% and 74%, respectively but based on the renal units, it was 66%, 81%, 46%, 91% and 79% , respectively. Although Doppler Ultrasound has the potential for identifying acute pyelonephritis in children, but it is still soon to replace DMSA scan.

  9. Evaluation of pelvic varicose veins using color Doppler ultrasound: comparison of results obtained with ultrasound of the lower limbs, transvaginal ultrasound, and phlebography Avaliação de varizes pélvicas por Doppler colorido: comparação dos resultados obtidos com ultrassom dos membros inferiores, ultrassom transvaginal e flebografia

    Directory of Open Access Journals (Sweden)

    Fanilda Souto Barros

    2010-06-01

    étodos diagnósticos não-invasivos mais comumente usados para avaliar a insuficiência venosa pélvica, enquanto a flebografia ainda é considerada como o padrão-ouro. Objetivos: Determinar a prevalência de varizes dos membros inferiores originadas na pélvis em um grupo de pacientes do sexo feminino e determinar a concordância entre os resultados obtidos por Doppler colorido dos membros inferiores, ultrassom transvaginal e flebografia. Métodos: A AMOstra incluiu pacientes do sexo feminino encaminhadas para o laboratório vascular para triagem dos membros inferiores. As pacientes diagnosticadas com trombose venosa profunda foram excluídas. A análise dos dados incluiu o coeficiente de concordância kappa, o teste de McNemar e os valores de sensibilidade e especificidade. Resultados: De um total de 1.020 pacientes, 124 (12.2% tiveram achados compatíveis com refluxo de origem pélvica. Entre essas pacientes, 51 (41.2% eram casos recorrentes. Um total de 249 foram submetidas a ultrassom transvaginal. Houve concordância significativa entre os achados ultrassonográficos dos membros inferiores e os achados transvaginais. A flebografia foi realizada em 54 pacientes. A comparação entre o ultrassom transvaginal e a flebografia foi associada a 96.2% de sensibilidade e 100% de especificidade. Conclusões: OS AUTores chamam a atenção para a prevalência relativamente alta de varizes dos membros inferiores originadas na pélvis, sugerindo uma importante, embora subdiagnosticada, causa de varizes recorrentes.

  10. Endosonographic and color doppler flow imaging alterations observed within irradiated rectal cancer

    International Nuclear Information System (INIS)

    Alexander, Archie A.; Palazzo, Juan P.; Ahmad, Neelofur R.; Liu, J.-B.; Forsberg, Flemming; Marks, John

    1996-01-01

    Purpose: To correlate the endosonographic and color Doppler flow imaging alterations observed in irradiated rectal cancers with the pathologic features of radiation response, and to evaluate the potential impact of altered blood flow on the integrity of the surgical anastamosis. Methods and Materials: Endosonography with color and pulsed wave Doppler was performed on 20 rectal cancer masses before and after high dose preoperative radiation (XRT). Pre- and post-XRT observations included comparing alterations in tumor size, sonographic echotexture, color Doppler flow, and pulsatility indices. Comparisons were made with pathologic findings in the irradiated specimens and with the incidence of anastomotic failure. Results: Compared to pre-XRT observations, irradiated rectal cancers decreased in size and became either mixed in echogenicity with less apparent color Doppler flow (16 of 20) or unchanged in color Doppler flow and echotexture (4 of 20). Those with less flow (16 of 20) were imaged later (mean = 90.2 ± 12.1 days) than those without change in color Doppler flow (mean = 21.7 ± 2.7 days). Pathologically, the group of four without change in color Doppler signal had features of acute inflammation which were not observed in 16 of 20 imaged later. Based on pulsatility index measurements, both high and low resistance vessels were detected and confirmed by immunohistochemical staining, and features of postradiation obliterative vasculitis were observed. Only one primary anastomosis in 14 patients with decreased flow failed. Conclusions: The sonographic and color Doppler flow imaging alterations observed within irradiated rectal cancer correlated with changes of postradiation obliterative vasculitis. The apparent diminished local blood flow within high and low resistance vessels post-XRT did not result in an increased incidence of anastomotic failures

  11. Imagens ultra-sonográficas do plexo braquial na região axilar Imágenes ultra-sonográficas del plexo braquial en la región axilar Ultrasound images of the brachial plexus in the axillary region

    Directory of Open Access Journals (Sweden)

    Diogo Brüggemann da Conceição

    2007-12-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A artéria axilar é referência anatômica de superfície para o bloqueio do plexo braquial por via axilar. Estudos anatômicos sugerem variabilidade das posições das estruturas nervosas do plexo braquial em relação à artéria. Essas variações podem dificultar bloqueios por neuroestimulação. A ultra-sonografia permite a identificação das estruturas do plexo braquial ¹. Este estudo visou a descrever o posicionamento dos nervos do plexo braquial em relação à artéria axilar. MÉTODO: Foram estudados 30 voluntários de ambos os sexos, em posição supina com abdução a 90º e rotação externa do ombro e flexão do cotovelo a 90º. Utilizando transdutor digital de 5 cm e 5-10 MHz, foram identificados os nervos mediano, ulnar e radial e as respectivas posições em relação à artéria foram marcadas em uma carta gráfica seccional de oito setores, numerados em ordem crescente a partir da hora 12 (medial, cujo centro representava a artéria axilar. RESULTADOS: O nervo mediano localizou-se predominante no setor 8 (55% e no setor 1 (28% (mediais; o nervo radial localizou-se predominantemente nos setores 4 (59% e 5 (34% (laterais e o nervo ulnar nos setores 2 e 3 (inferiores em 69% e 24% dos casos, respectivamente. Houve considerável variação da localização dos nervos em relação aos aspectos superior e inferior da artéria. CONCLUSÕES: A inspeção em tempo real, por ultra-som, das estruturas neurovasculares do plexo braquial na axila mostrou que os nervos mediano, ulnar e radial podem apresentar diferentes relações com a artéria axilar.JUSTIFICATIVA Y OBJETIVOS: La arteria axilar es una referencia anatómica de superficie para el bloqueo del plexo braquial por vía axilar. Estudios anatómicos sugieren variabilidad de las posiciones de las estructuras nerviosas del plexo braquial con relación a la arteria. Esas variaciones pueden dificultar bloqueos por neuro estimulación. El ultrasonido

  12. Tissue Doppler echocardiography – A case of right tool, wrong use

    Directory of Open Access Journals (Sweden)

    Thomas George

    2004-08-01

    Full Text Available Abstract Background The developments in echocardiography or ultrasound cardiography (UCG have improved our clinical capabilities. However, advanced hardware and software capabilities have resulted in UCG facilities of dubious clinical benefits. Is tissue Doppler echocardiography (TDE is one such example? Presentation of the hypothesis TDE has been touted as advancement in the field of echocardiography. The striking play of colors, impressive waveforms and the seemingly accurate velocity values could be deceptive. TDE is a clear case of inappropriate use of technology. Testing the hypothesis To understand this, a comparison between flow Doppler and tissue Doppler is made. To make clinically meaningful velocity measurements with Doppler, we need prior knowledge of the line of motion. This is possible in blood flow but impossible in the complex myocardial motion. The qualitative comparison makes it evident that Doppler is best suited for flow studies. Implications of the hypothesis As of now TDE is going backwards using an indirect method when direct methods are better. The work on TDE at present is only debatable 'research and publication' material and do not translate into tangible clinical benefits. There are several advances like curved M-mode, strain rate imaging and tissue tracking in TDE. However these have been disappointing. This is due to the basic flaw in the application of the principles of Doppler. Doppler is best suited for flow studies and applying it to tissue motion is illogical. All data obtained by TDE is scientifically incorrect. This makes all the published papers on the subject flawed. Making diagnostic decisions based on this faulty application of technology would be unacceptable to the scientific cardiologist.

  13. Phylloedes tumor of breast: findings at mammography, sonography and color Doppler imaging

    International Nuclear Information System (INIS)

    Park, Kun Choon; Ahn, Sei Hyun; Kim, Young Hwan; Choi, Hye Yong; Baek, Seung Yon; Yoon, Jeong Hyun

    1994-01-01

    The phylloides tumor of the breast is rare. the purposes of this study were to find the characteristic findings at mammography, sonography, and color Doppler imaging and to evaluate the usefulness of color Doppler study as an additional modality in the diagnosis of phylloides tumor and differentiation between benign and malignant varieties. Eight cases, who were pathologically proven as pylloides tumors, were retrospectively studied. The findings at histologic examination suggested benign in five, malignantin two, and borderline in one. We analyzed the mammograms of all eight patients and sonogram and color Doppler images of four patients. Phylloides tumors were seen as dense masses with lobulated margins in mammograms. On sonography, they showed relatively well-defined masses with in homogenous internal echo pattern and central echogenic areas. They were characterized by the presence of arterial and venous flows in the center and periphery of the lesion on color Doppler imaging and spectral analysis. We conclude that mammographic, sonographic and even color Doppler findings are not predictive of benign or malignant nature of the phylloides tumor. However, mammography and sonography with color Doppler interrogation are helpful in the diagnosis of phylloides tumor

  14. TORSION TESTIS : ROLE OF COLOR DOPPLER : A STUDY OF 50 CASES

    Directory of Open Access Journals (Sweden)

    Anand

    2015-09-01

    Full Text Available BACKGROUND: T orsion testis is one of the catast r ophic conditions in children and young a d u lts. Traditionally the diagnosis was made clinical presentation and suspicion. Critical decision making is essential to save the testis . OBJECTIVE: To study the usefu lness and efficacy of Doppler ultrasound in correctly diagnosing acute scrotal conditions in children and young adults to save the testis and to avoid negative explorations. METHODS: Over a period of two years 50 patients with acute scrotum were admitted i n general surgery department who underwent Doppler ultrasound scrotum and its efficacy in correctly diagnosing the pathology was analysed. RESULTS: 50 patients with age group <25 years were included in study. Scrotal pain was the most frequent presenting s ymptom of acute scrotum (98% followed by Swelling of the hemiscrolum on the involved side present in 86% of the patients. Doppler ultrasound showed torsion of testis in 18 patients. On Scrotal exploration, torsion of spermatic cord was confirmed in 16 pat ients, one patient had torsion of appendix of testis and the other had Epididymo - orchitis. Thus the sensitivity and specificity of Doppler ultrasonography for testicular torsion was 86.9% and 92.6% respectively. 2 patients with equivocal Doppler findings, but strong clinical suspicion of testicular torsion were explored, and testis was found to be torsed in both two patients. Doppler ultrasonography showed Epididymo - orchitis in 22 patients, torsion of testicular appendage in 2 patients, Idiopathic scrotal edema in one, and in 5 pts no significant pathology found. All twenty patients of epididymo - orchitis, two patients of torsion of testicular appendage, and one patient of idiopathic scrotal edema were managed conservatively. At three weeks follow up, all th e patients were free of symptoms. The sensitivity and specificity of Doppler ultrasonography for epididymo - orchitis was 95% and 100% respectively. CONCLUSIONS: color

  15. High-frequency Doppler ultrasound transducer for the peripheral circulatory system

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Youngmin; Yang, Jeongwon; Kang, Uk; Kim, Guanghoon [Korea Electrotechnology Research Institute, Ansan (Korea, Republic of)

    2011-12-15

    A Doppler ultrasound transducer was designed and implemented to measure the blood flow velocity in tiny vessels near the skin of hands or feet. The geometric parameters of the transducer for defining the observation volume were derived and implemented with an acoustic window made of polystyrene. The observation volume designed in this study was located 6.5 mm from the transducer, which was comparable to the value predicted geometrically. The two-way insertion loss of the transducer was -11.3 dB on ultrasound frequency of 20 MHz, and the 3-dB bandwidth was approximately 2 MHz. In addition, the Doppler shift in the frequency measured by using a Doppler device composed of the transducer and a Doppler signal processing unit was proportional to the flow velocity generated by a homemade flowing system. Finally, we concluded that the transducer could be applied to measure the blood flow velocity in hands or feet.

  16. High-frequency Doppler ultrasound transducer for the peripheral circulatory system

    International Nuclear Information System (INIS)

    Bae, Youngmin; Yang, Jeongwon; Kang, Uk; Kim, Guanghoon

    2011-01-01

    A Doppler ultrasound transducer was designed and implemented to measure the blood flow velocity in tiny vessels near the skin of hands or feet. The geometric parameters of the transducer for defining the observation volume were derived and implemented with an acoustic window made of polystyrene. The observation volume designed in this study was located 6.5 mm from the transducer, which was comparable to the value predicted geometrically. The two-way insertion loss of the transducer was -11.3 dB on ultrasound frequency of 20 MHz, and the 3-dB bandwidth was approximately 2 MHz. In addition, the Doppler shift in the frequency measured by using a Doppler device composed of the transducer and a Doppler signal processing unit was proportional to the flow velocity generated by a homemade flowing system. Finally, we concluded that the transducer could be applied to measure the blood flow velocity in hands or feet.

  17. Proposed protocols for peripheral and renal Doppler

    International Nuclear Information System (INIS)

    Fonseca Portuguez, Adriana

    2009-01-01

    A literature review was performed in order to prepare a summary of the important concepts of Doppler and applications in peripheral vascular evaluation and renal. The normal characteristics are summarized and explained in each vascular system and diagnostic criteria of the disorders frequently encountered in practice. Requested more studies have been identified and proposed protocols and report sheets have been developed to standardize the methodology of realization of several Doppler studies. The variability between operators has been treated to reduce as much as possible and follow-up studies have provided in patients who need. (author) [es

  18. Doppler broadening of cross sections

    International Nuclear Information System (INIS)

    Buckler, P.A.C.; Pull, I.C.

    1962-12-01

    Expressions for temperature dependent cross-sections in terms of resonance parameters are obtained, involving generalisations of the conventional Doppler functions, ψ and φ. Descriptions of Fortran sub-routines, which calculate broadened cross-sections in accordance with the derived formulae, are included. (author)

  19. Cisto de colédoco: experiência de cinco anos com o tratamento cirúrgico no hospital municipal JESUS-RJ

    Directory of Open Access Journals (Sweden)

    Lisieux Eyer de Jesus

    Full Text Available OBJETIVO: Relatar a experiência no diagnóstico e tratamento do cisto de colédoco no Hospital Municipal Jesus em cinco anos (1996-2001 e a experiência brasileira publicada para o tratamento do cisto de colédoco em crianças. MÉTODO: Avaliação prospectiva dos pacientes operados com o diagnóstico de cisto de colédoco em cinco anos no Hospital Municipal Jesus. RESULTADOS: Houve predomínio de casos diagnosticados pela presença de dor abdominal recorrente, icterícia e/ou massa abdominal palpável. Apenas dois pacientes apresentavam a tríade completa. Todos os pacientes foram submetidos à ultra-sonografia e houve dúvida no diagnóstico ultra-sonográfico em apenas dois. Todos eram cistos do tipo 1 de Todani tratados através de ressecção completa e anastomose biliodigestiva em Y Roux. Houve complicações pós-operatórias imediatas em três pacientes: um caso de hemorragia digestiva alta e dois casos de fístula biliar, um deles relacionado a problemas técnicos na anastomose que necessitou de reoperação. O seguimento variou de quatro meses a cinco anos, sem detecção de complicação tardia em nenhum caso. CONCLUSÕES: O tratamento do cisto de colédoco através da ressecção completa na criança é seguro, relacionado a poucas complicações e capaz de resolver por completo a sintomatologia pré-operatória dos pacientes.

  20. A simplified study of trans-mitral Doppler patterns

    Directory of Open Access Journals (Sweden)

    Thomas George

    2008-11-01

    Full Text Available Abstract Background Trans-mitral Doppler produces complex patterns with a great deal of variability. There are several confusing numerical measures and indices to study these patterns. However trans-mitral Doppler produces readymade data visualization by pattern generation which could be interpreted by pattern analysis. By following a systematic approach we could create an order and use this tool to study cardiac function. Presentation of the hypothesis In this new approach we eliminate the variables and apply pattern recognition as the main criterion of study. Proper terminologies are also devised to avoid confusion. In this way we can get some meaningful information. Testing the hypothesis Trans-mitral Doppler should be seen as patterns rather than the amplitude. The hypothesis can be proven by logical deduction, extrapolation and elimination of variables. Trans-mitral flow is also analyzed vis-à-vis the Starling's Law applied to the left atrium. Implications of the hypothesis Trans-mitral Doppler patterns are not just useful for evaluating diastolic function. They are also useful to evaluate systolic function. By following this schema we could get useful diagnostic information and therapeutic options using simple pattern recognition with minimal measurements. This simplified but practical approach will be useful in day to day clinical practice and help in understanding cardiac function better. This will also standardize research and improve communication.

  1. Radar Micro-Doppler Feature Extraction Using the Singular Value Decomposition

    NARCIS (Netherlands)

    Wit, J.J.M. de; Harmanny, R.I.A.; Molchanov, P.

    2014-01-01

    Abstract—The micro-Doppler spectrogram depends on parts of a target moving and rotating in addition to the main body motion (e.g., spinning rotor blades) and is thus characteristic for the type of target. In this study, the micro-Doppler spectrogram is exploited to distinguish between birds and

  2. Acoustic doppler methods for remote measurements of ocean flows - a review

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.

    The evolution of acoustic doppler methods for remote measurements of ocean flows has been briefly reviewed in historical perspective. Both Eulerian and profiling methods have been discussed. Although the first acoustic Doppler current meter has been...

  3. Avaliação do ventrículo direito pelo ecocardiograma com doppler tecidual na embolia pulmonar aguda

    Directory of Open Access Journals (Sweden)

    Ana Clara Tude Rodrigues

    2013-06-01

    Full Text Available FUNDAMENTO: A avaliação da função Ventricular Direita (VD pelo ecocardiograma em pacientes com Tromboembolismo Pulmonar (TEP é complexa, frequentemente qualitativa; o Doppler tecidual tem sido utilizado para avaliação semiquantitativa dessa câmara, com algumas limitações. OBJETIVO: Avaliar a função do VD no TEP pelo ecocardiograma com Doppler tecidual, complementando com o peptídeo atrial natriurético (BNP. MÉTODOS: Foram estudados pacientes com TEP pelo ecocardiograma com Doppler tecidual e BNP até 24 horas do diagnóstico, obtendo-se as velocidades miocárdicas (s', strain, strain rate e índice de performance miocárdica do VD; disfunção do VD foi iagnosticada por hipocinesia da câmara, movimento anormal septal e relação VD/VE >1. De acordo com o BNP os pacientes foram divididos em Grupo I, BNP 50 pg/mL. RESULTADOS: De 118 pacientes, 100 (60 homens, idade = 55 ± 17 anos foram analisados; observou-se disfunção do VD em 28%, mais frequentemente no grupo II (19 vs. 9 pacientes, p < 0,001. O grupo II era mais idoso (64 ± 19 vs. 50 ± 15 anos, apresentava menor velocidade de s' (10,5 ± 3,5 vs. 13,2 ± 3,1 cm/s e maior pressão pulmonar (48 ± 11 vs. 35 ± 11 mmHg, p < 0,001 para todos. O ponto de corte de s' para disfunção do VD foi de 10,8 cm/s (especificidade = 85%, sensibilidade = 54%, com moderada correlação entre o BNP e a onda s'(r = -0,39. CONCLUSÃO: No TEP, a disfunção do VD pelo ecocardiograma se acompanha de elevação do BNP; apesar confirmar adequadamente a presença de disfunção do VD, o Doppler tecidual apresenta sensibilidade limitada para este diagnóstico.

  4. Developments in target micro-Doppler signatures analysis: radar imaging, ultrasound and through-the-wall radar

    OpenAIRE

    Clemente, C.; Balleri, A.; Woodbridge, K.; Soraghan, J. J.

    2013-01-01

    Target motions, other than the main bulk translation of the target, induce Doppler modulations around the main Doppler shift that form what is commonly called a target micro-Doppler signature. Radar micro-Doppler signatures are generally both target and action speci c and hence can be used to classify and recognise targets as well as to identify possible threats. In recent years, research into the use of micro-Doppler signatures for target classi cation to address many defence and security ch...

  5. Numerical stud of glare spot phase Doppler anemometry

    OpenAIRE

    Hespel , Camille; Ren , Kuan Fang; Gréhan , Gérard; Onofri , Fabrice

    2008-01-01

    International audience; The phase Doppler anemometry has (PDA) been developed to measure simultaneously the velocity and the size of droplets. When the concentration of particles is high, tightly focused beams must be used, as in the dual burst PDA. The latter permits an access to the refractive index of the particle, but the effect of wave front curvature of the incident beams becomes evident. In this paper, we introduce a glare spot phase Doppler anemometry which uses two large beams. The i...

  6. Transcranial Doppler ultrasound and cerebral angiography - alternative or complementary

    International Nuclear Information System (INIS)

    Bockenheimer, S.; Lorey, N.

    1985-01-01

    Transcranial Doppler ultrasound is a noninvasive method of recording the flow velocity of larger intracranial vessels. The impact on diagnosis of cerebravascular occlusive disease is not yet evaluated. We present 15 patients, age range 39-73 years, who suffered from completed stroke. The findings of transcranial Doppler ultrasound and of cerebral angiography are presented. The value of both methods in treatment strategy is discussed. (orig.) [de

  7. Predictable progressive Doppler deterioration in IUGR: does it really exist?

    LENUS (Irish Health Repository)

    Unterscheider, Julia

    2013-12-01

    An objective of the Prospective Observational Trial to Optimize Pediatric Health in IUGR (PORTO) study was to evaluate multivessel Doppler changes in a large cohort of intrauterine growth restriction (IUGR) fetuses to establish whether a predictable progressive sequence of Doppler deterioration exists and to correlate these Doppler findings with respective perinatal outcomes.

  8. The use ofDoppler velocitnetry ofthe utnbilical artery before 24 ...

    African Journals Online (AJOL)

    growth retardation with umbilical artery Doppler ultrasonography. BM] 1989; 298: 631-635. 12. Schulman H, Winter D, Farmakides G, er al. Pregnancy surveil- lance with Doppler velocimerry of the uterine and umbilical arter- ies. Am] Obstet Gyneco11989; 160: 192-196. 13. Hanrerry KP, Primrose MH, Neilson JP, Whittle MJ.

  9. [Doppler echocardiography of tricuspid insufficiency. Methods of quantification].

    Science.gov (United States)

    Loubeyre, C; Tribouilloy, C; Adam, M C; Mirode, A; Trojette, F; Lesbre, J P

    1994-01-01

    Evaluation of tricuspid incompetence has benefitted considerably from the development of Doppler ultrasound. In addition to direct analysis of the valves, which provides information about the mechanism involved, this method is able to provide an accurate evaluation, mainly through use of the Doppler mode. In addition to new criteria being evaluated (mainly the convergence zone of the regurgitant jet), some indices are recognised as good quantitative parameters: extension of the regurgitant jet into the right atrium, anterograde tricuspid flow, laminar nature of the regurgitant flow, analysis of the flow in the supra-hepatic veins, this is only semi-quantitative, since the calculation of the regurgitation fraction from the pulsed Doppler does not seem to be reliable; This accurate semi-quantitative evaluation is made possible by careful and consistent use of all the criteria available. The authors set out to discuss the value of the various evaluation criteria mentioned in the literature and try to define a practical approach.

  10. Contrast-enhanced power Doppler US in the characterization of renal masses

    International Nuclear Information System (INIS)

    Ascenti, G.; Zimbaro, G.; Mazziotti, S.; Visalli, C.; Racchiusa, S.; Vinci, S.; Scribano, E.

    2000-01-01

    Purpose of this work is to report the results of a prospective study investigating the potentials of contrast-enhanced power Doppler in the diagnosis of expansive renal lesions. From 1997 to October 30, 1999, it was studied the case of 59 expansive renal lesions (28 malignant, 31 benign) in 48 patients (mean age 55 years, range 10-79) with power Doppler US before and after the administration of an echo-enhancing agent (Levovist, Schering AG, Berlin Germany). Were found 5 patterns of vascular architecture of the lesions, both before and after contrast agent administration, following the classification by Jinzaki e Coll. Power Doppler US showed vascular structures in 34 patients. The administration of Levovist revealed vessels in 12/25 lesions which had none at baseline studies and in 6 cases vascularity was particularly evident. Color signals were enhanced in all the 34 vascularized lesions, which allowed better definition of vascular patterns. The characterization of vascular patterns with baseline power Doppler US helped improve diagnostic accuracy compared to gray-scale US (58% versus 32%) for hyperechoic lesions, complex cysts and pseudomasses. Independent of contrast agent administration, the integration of gray-scale and power Doppler modes increased diagnostic accuracy even further (76% correct diagnoses). In our series, the US contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions; conversely, Levovist can be advantageous for the characterization of suspected pseudomasses and complex cysts [it

  11. Micro-Doppler Ambiguity Resolution for Wideband Terahertz Radar Using Intra-Pulse Interference.

    Science.gov (United States)

    Yang, Qi; Qin, Yuliang; Deng, Bin; Wang, Hongqiang; You, Peng

    2017-04-29

    Micro-Doppler, induced by micro-motion of targets, is an important characteristic of target recognition once extracted via parameter estimation methods. However, micro-Doppler is usually too significant to result in ambiguity in the terahertz band because of its relatively high carrier frequency. Thus, a micro-Doppler ambiguity resolution method for wideband terahertz radar using intra-pulse interference is proposed in this paper. The micro-Doppler can be reduced several dozen times its true value to avoid ambiguity through intra-pulse interference processing. The effectiveness of this method is proved by experiments based on a 0.22 THz wideband radar system, and its high estimation precision and excellent noise immunity are verified by Monte Carlo simulation.

  12. A Comprehensive Radial Velocity Error Budget for Next Generation Doppler Spectrometers

    Science.gov (United States)

    Halverson, Samuel; Ryan, Terrien; Mahadevan, Suvrath; Roy, Arpita; Bender, Chad; Stefansson, Guomundur Kari; Monson, Andrew; Levi, Eric; Hearty, Fred; Blake, Cullen; hide

    2016-01-01

    We describe a detailed radial velocity error budget for the NASA-NSF Extreme Precision Doppler Spectrometer instrument concept NEID (NN-explore Exoplanet Investigations with Doppler spectroscopy). Such an instrument performance budget is a necessity for both identifying the variety of noise sources currently limiting Doppler measurements, and estimating the achievable performance of next generation exoplanet hunting Doppler spectrometers. For these instruments, no single source of instrumental error is expected to set the overall measurement floor. Rather, the overall instrumental measurement precision is set by the contribution of many individual error sources. We use a combination of numerical simulations, educated estimates based on published materials, extrapolations of physical models, results from laboratory measurements of spectroscopic subsystems, and informed upper limits for a variety of error sources to identify likely sources of systematic error and construct our global instrument performance error budget. While natively focused on the performance of the NEID instrument, this modular performance budget is immediately adaptable to a number of current and future instruments. Such an approach is an important step in charting a path towards improving Doppler measurement precisions to the levels necessary for discovering Earth-like planets.

  13. Ultra-high temperature direct propulsion

    International Nuclear Information System (INIS)

    Araj, K.J.; Slovik, G.; Powell, J.R.; Ludewig, H.

    1987-01-01

    Potential advantages of ultra-high exhaust temperature (3000 K - 4000 K) direct propulsion nuclear rockets are explored. Modifications to the Particle Bed Reactor (PBR) to achieve these temperatures are described. Benefits of ultra-high temperature propulsion are discussed for two missions - orbit transfer (ΔV = 5546 m/s) and interplanetary exploration (ΔV = 20000 m/s). For such missions ultra-high temperatures appear to be worth the additional complexity. Thrust levels are reduced substantially for a given power level, due to the higher enthalpy caused by partial disassociation of the hydrogen propellant. Though technically challenging, it appears potentially feasible to achieve such ultra high temperatures using the PBR

  14. Carotid Doppler ultrasound findings in patients with left ventricular assist devices.

    Science.gov (United States)

    Cervini, Patrick; Park, Soon J; Shah, Dipesh K; Penev, Irina E; Lewis, Bradley D

    2010-12-01

    Left ventricular assist devices (LVADs) have been used to treat advanced heart failure refractory to medical management, as bridge therapy to myocardial recovery, as bridge therapy to cardiac transplantation, or as destination therapy for patients with unfavorable transplant candidacy. Neurologic complications are some of the most common and devastating complications in these patients. Preoperative carotid ultrasound is, therefore, a standard evaluation in patients at risk for cerebrovascular disease. Postoperative carotid artery Doppler sonography is performed in those patients with neurologic symptoms. It is likely, therefore, that sonographers, radiologists, and other physicians working in a center where LVADs are implanted will likely encounter a carotid artery Doppler study in this patient group. To our knowledge, the carotid Doppler findings in these patients have never been published. We review the Doppler ultrasound findings in 6 patients after LVAD insertion.

  15. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2001-10-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses tasks performed in the fourth quarter as well as the other three quarters of the past year. The subjects that were covered in previous reports and that are also discussed in this report include: Analysis of field laboratory data of active cement applications from three oil-well service companies; Preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; Summary of pertinent information from Russian ultra-lightweight cement literature review; and Comparison of compressive strengths of ULHS systems using ultrasonic and crush methods Results reported from the fourth quarter include laboratory testing of ULHS systems along with other lightweight cement systems--foamed and sodium silicate slurries. These comparison studies were completed for two different densities (10.0 and 11.5 lb/gal) and three different field application scenarios. Additional testing included the mechanical properties of ULHS systems and other lightweight systems. Studies were also performed to examine the effect that circulation by centrifugal pump during mixing has on breakage of ULHS.

  16. Narrowing of electromagnetically induced transparency resonance in a Doppler-broadened medium

    International Nuclear Information System (INIS)

    Javan, Ali; Kocharovskaya, Olga; Lee Hwang; Scully, Marlan O.

    2002-01-01

    We derive an analytic expression for the linewidth of electromagnetically induced transparency (EIT) resonance in a Doppler-broadened system. It is shown here that for relatively low intensity of the driving field the EIT linewidth is proportional to the square root of intensity and is independent of the Doppler width, similar to the laser-induced line narrowing effect described by Feld and Javan. In the limit of high intensity we recover the usual power-broadening case where the EIT linewidth is proportional to the intensity and inversely proportional to the Doppler width

  17. Theoretical study of electromagnetically induced transparency in a five-level atom and application to Doppler-broadened and Doppler-free Rb atoms

    International Nuclear Information System (INIS)

    Bhattacharyya, Dipankar; Ray, Biswajit; Ghosh, Pradip N

    2007-01-01

    We report theoretical studies of a Λ-type five-level atomic system. The density matrix equations are set up and solved numerically to obtain the probe absorption line shape of Rb D 2 transitions for cold (Doppler-free) and room temperature (Doppler-broadened) atoms. Simulated spectra for Doppler-broadened systems lead to four velocity-selective dips along with an electromagnetic induced transparency (EIT) peak as observed earlier from the co-propagating pump-probe spectroscopy of Rb D 2 transitions. Effects of pump power and spontaneous decay rate from the upper levels on the simulated spectra are also studied. For cold atoms a very pronounced EIT peak is observed when the pump frequency is on resonance with one allowed transition. We find that lower pump power leads to a much sharper EIT signal in this case. A simulated dispersion curve shows a rapid variation of the refractive index that may lead to a sharp reduction of the group velocity of photons

  18. Ultrasonic intrusion sensor using the Doppler effect; Choonpa Doppler hoshiki shinnyu sensor

    Energy Technology Data Exchange (ETDEWEB)

    Kani, H; Iwasaki, N; Goto, M [Nippon Soken, Inc., Tokyo (Japan); Tsuzuki, T; Nakamura, T [Denso Corp., Aichi (Japan)

    1997-10-01

    For vehicle anti-theft alarm systems which cope with vehicle and car component theft, EU initiated vehicle security regulations from Jan 1997. Also, the insurance industry has instituted the insurance certification of vehicle anti-theft alarm systems. We have developed an ultrasonic intrusion sensor using the doppler effect for vehicle anti-theft alarm systems specifically for these EU regulations and insurance certification. 2 refs., 7 figs., 1 tab.

  19. Imaging doppler lidar for wind turbine wake profiling

    Science.gov (United States)

    Bossert, David J.

    2015-11-19

    An imaging Doppler lidar (IDL) enables the measurement of the velocity distribution of a large volume, in parallel, and at high spatial resolution in the wake of a wind turbine. Because the IDL is non-scanning, it can be orders of magnitude faster than conventional coherent lidar approaches. Scattering can be obtained from naturally occurring aerosol particles. Furthermore, the wind velocity can be measured directly from Doppler shifts of the laser light, so the measurement can be accomplished at large standoff and at wide fields-of-view.

  20. Radar micro-Doppler of wind turbines : Simulation and analysis using rotating linear wire structures

    NARCIS (Netherlands)

    Krasnov, O.A.; Yarovoy, A.

    2015-01-01

    A simple electromagnetic model of wind-turbine's main structural elements as the linear wired structures is developed to simulate the temporal patterns of observed radar return Doppler spectra (micro-Doppler). Using the model, the micro-Doppler for different combinations of the turbines rotation

  1. Consumers' conceptualization of ultra-processed foods.

    Science.gov (United States)

    Ares, Gastón; Vidal, Leticia; Allegue, Gimena; Giménez, Ana; Bandeira, Elisa; Moratorio, Ximena; Molina, Verónika; Curutchet, María Rosa

    2016-10-01

    Consumption of ultra-processed foods has been associated with low diet quality, obesity and other non-communicable diseases. This situation makes it necessary to develop educational campaigns to discourage consumers from substituting meals based on unprocessed or minimally processed foods by ultra-processed foods. In this context, the aim of the present work was to investigate how consumers conceptualize the term ultra-processed foods and to evaluate if the foods they perceive as ultra-processed are in concordance with the products included in the NOVA classification system. An online study was carried out with 2381 participants. They were asked to explain what they understood by ultra-processed foods and to list foods that can be considered ultra-processed. Responses were analysed using inductive coding. The great majority of the participants was able to provide an explanation of what ultra-processed foods are, which was similar to the definition described in the literature. Most of the participants described ultra-processed foods as highly processed products that usually contain additives and other artificial ingredients, stressing that they have low nutritional quality and are unhealthful. The most relevant products for consumers' conceptualization of the term were in agreement with the NOVA classification system and included processed meats, soft drinks, snacks, burgers, powdered and packaged soups and noodles. However, some of the participants perceived processed foods, culinary ingredients and even some minimally processed foods as ultra-processed. This suggests that in order to accurately convey their message, educational campaigns aimed at discouraging consumers from consuming ultra-processed foods should include a clear definition of the term and describe some of their specific characteristics, such as the type of ingredients included in their formulation and their nutritional composition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Transthoracic Doppler echocardiography to predict optimal tube pulsing window for coronary artery CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Gang, E-mail: cjr.sungang@vip.163.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Li, Min, E-mail: limin22000@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Jiang, Xiang-sen, E-mail: jiangxiangsen123@126.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Li, Li, E-mail: leely1976@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Peng, Zhao-hui, E-mail: zhaohuipeng_R@163.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China); Mu, Nan-nan, E-mail: munannan22000@sohu.com [Department of Medical Imaging, Jinan Military General Hospital, No. 25, Shifan Road, Jinan, Shandong Province 250031 (China)

    2012-09-15

    Rationale and objective: To evaluate the feasibility of transthoracic Doppler echocardiography to determine the optimal pulsing windows for CT coronary angiography to narrow the pulsing windows further, especially in higher heart rate. Materials and methods: Doppler was performed on 135 patients before CT scanning. For Doppler, the intervals with minimal motion were evaluated during both systole and diastole integrating electrocardiogram (ECG) intervals. For CT scanning, the retrospective ECG-gating was applied and the optimal reconstruction intervals were determined. The accuracy of Doppler analysis to predict the optimal reconstruction intervals was tested. The predicted length of pulsing windows was compared between Doppler analysis and traditional prospective ECG-gating protocol (heart rate ≦ 65 bpm, 60–76%; 66–79 bpm, 30–77%; ≧80 bpm, 31–47%). Results: According to Doppler analysis, the mean length of intervals with minimal motion in systole was 106.4 ± 39.2 ms and 125.2 ± 92.0 ms in diastole. When the intervals with minimal motion during diastole > 90 ms, the optimal reconstruction intervals were located at diastole; otherwise, at systole (P < 0.001). The optimal reconstruction intervals in 93.8% (132/135) patients could be predicted accurately by Doppler analysis. If the optimal reconstruction intervals predicted by Doppler were applied as the exposure windows, the mean length of pulsing windows should has been 105.2 ± 69.4 ms (range: 26.9–510.3 ms), which was significantly shorter than that of traditional prospective ECG-gating protocol (232.0 ± 120.2 ms, range: 93.2–427.3 ms, P < 0.001). Conclusion: Doppler can help detecting the optimal pulsing windows accurately. Prospective ECG-gating incorporating Doppler analysis may narrow pulsing windows significantly while maintaining image quality.

  3. Transthoracic Doppler echocardiography to predict optimal tube pulsing window for coronary artery CT angiography

    International Nuclear Information System (INIS)

    Sun, Gang; Li, Min; Jiang, Xiang-sen; Li, Li; Peng, Zhao-hui; Mu, Nan-nan

    2012-01-01

    Rationale and objective: To evaluate the feasibility of transthoracic Doppler echocardiography to determine the optimal pulsing windows for CT coronary angiography to narrow the pulsing windows further, especially in higher heart rate. Materials and methods: Doppler was performed on 135 patients before CT scanning. For Doppler, the intervals with minimal motion were evaluated during both systole and diastole integrating electrocardiogram (ECG) intervals. For CT scanning, the retrospective ECG-gating was applied and the optimal reconstruction intervals were determined. The accuracy of Doppler analysis to predict the optimal reconstruction intervals was tested. The predicted length of pulsing windows was compared between Doppler analysis and traditional prospective ECG-gating protocol (heart rate ≦ 65 bpm, 60–76%; 66–79 bpm, 30–77%; ≧80 bpm, 31–47%). Results: According to Doppler analysis, the mean length of intervals with minimal motion in systole was 106.4 ± 39.2 ms and 125.2 ± 92.0 ms in diastole. When the intervals with minimal motion during diastole > 90 ms, the optimal reconstruction intervals were located at diastole; otherwise, at systole (P < 0.001). The optimal reconstruction intervals in 93.8% (132/135) patients could be predicted accurately by Doppler analysis. If the optimal reconstruction intervals predicted by Doppler were applied as the exposure windows, the mean length of pulsing windows should has been 105.2 ± 69.4 ms (range: 26.9–510.3 ms), which was significantly shorter than that of traditional prospective ECG-gating protocol (232.0 ± 120.2 ms, range: 93.2–427.3 ms, P < 0.001). Conclusion: Doppler can help detecting the optimal pulsing windows accurately. Prospective ECG-gating incorporating Doppler analysis may narrow pulsing windows significantly while maintaining image quality

  4. Principles of doppler tomography

    International Nuclear Information System (INIS)

    Juhlin, P.

    1992-08-01

    This paper shows how the radon transform can be used to determine vector fields. A scheme to determine the velocity field of a moving fluid by measurements with a continuous doppler signal is suggested. When the flow is confined to a bounded domain, as is the case in most applications, it can be uniquely decomposed into one gradiental and one rotational part. The former vanishes if the fluid is incompressible and source-free, and the latter can be completely reconstructed by the methods proposed in this paper if the domain is simply connected. Special attention is paid to laminar flow in a long cylindrical vessel with circular cross-section. Under such conditions the flow profile becomes parabolic, which makes the vessel recognizable as a typical 'N-shaped' pattern in an image describing the rotation of the velocity field. The vessel yields the same doppler tomographic pattern, no matter how it is sectioned. The ideas presented should be applicable also when studying the flow in blood vessels, even if the flow profile in these is not quite parabolic. The discrepancies only make the 'N-shape' somewhat distorted

  5. Analysis of Doppler effect measurement in FCA cores using JENDL-3.2 library

    International Nuclear Information System (INIS)

    Okajima, Shigeaki

    1996-01-01

    For the evaluation of the calculation accuracy of the 238 U Doppler effect using JENDL-3.2 library, the previously measured Doppler reactivity worths in the FCA were systematically analyzed. In the analysis the Doppler reactivity worth was calculated by a first order perturbation theory. The calculated results were compared with those using JENDL-3.1 library. The JENDL-3.2 calculation in MOX fuel mock-up cores agrees well with the experimental values within the experimental error. In U-235/Pu fuel cores, the JENDL-3.2 calculation gives 12-15% larger Doppler reactivity worths than the JENDL-3.1 calculation. (author)

  6. Sex Difference in Draft-Legal Ultra-Distance Events - A Comparison between Ultra-Swimming and Ultra-Cycling.

    Science.gov (United States)

    Salihu, Lejla; Rüst, Christoph Alexander; Rosemann, Thomas; Knechtle, Beat

    2016-04-30

    Recent studies reported that the sex difference in performance in ultra-endurance sports such as swimming and cycling changed over the years. However, the aspect of drafting in draft-legal ultra-endurance races has not yet been investigated. This study investigates the sex difference in ultra-swimming and ultra-cycling draft-legal races where drafting - swimming or cycling behind other participants to save energy and have more power at the end of the race to overtake them, is allowed. The change in performance of the annual best and the annual three best in an ultra-endurance swimming race (16-km 'Faros Swim Marathon') over 38 years and in a 24-h ultra-cycling race ('World Cycling Race') over 13 years were compared and analysed with respect to sex difference. Furthermore, performances of the fastest female and male finishers ever were compared. In the swimming event, the sex difference of the annual best male and female decreased non-significantly (P = 0.262) from 5.3% (1976) to 1.0% (2013). The sex gap of speed in the annual three fastest swimmers decreased significantly (P = 0.043) from 5.9 ± 1.6% (1979) to 4.7 ± 3.1% (2013). In the cycling event, the difference in cycling speed between the annual best male and female decreased significantly (P = 0.026) from 33.31% (1999) to 10.89% (2011). The sex gap of speed in the annual three fastest decreased significantly (P = 0.001) from 32.9 ± 0.6% (1999) to 16.4 ± 5.9% (2011). The fastest male swimmer ever (swimming speed 5.3 km/h, race time: 03:01:55 h:min:s) was 1.5% faster than the fastest female swimmer (swimming speed 5.2 km/h, race time: 03:04:09 h:min:s). The three fastest male swimmers ever (mean 5.27 ± 0.13 km/h) were 4.4% faster than the three fastest female swimmers (mean 5.05 ± 0.20 km/h) (P swimming and cycling, the sex difference in the annual top and annual top three swimmers and cyclists decreased (i.e. non-linearly in swimmers and linearly in cyclists) over the years. The sex difference of the

  7. Development of Rayleigh Doppler lidar for measuring middle atmosphere winds

    Science.gov (United States)

    Raghunath, K.; Patra, A. K.; Narayana Rao, D.

    Interpretation of most of the middle and upper atmospheric dynamical and chemical data relies on the climatological description of the wind field Rayleigh Doppler lidar is one instrument which monitors wind profiles continuously though continuity is limited to clear meteorological conditions in the middle atmosphere A Doppler wind lidar operating in incoherent mode gives excellent wind and temperature information at these altitudes with necessary spectral sensitivity It observes atmospheric winds by measuring the spectral shift of the scattered light due to the motions of atmospheric molecules with background winds and temperature by spectral broadening The presentation is about the design and development of Incoherent Doppler lidar to obtain wind information in the height regions of 30-65 km The paper analyses and describes various types of techniques that can be adopted viz Edge technique and Fringe Imaging technique The paper brings out the scientific objectives configuration simulations error sources and technical challenges involved in the development of Rayleigh Doppler lidar The presentation also gives a novel technique for calibrating the lidar

  8. Color Doppler US of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, Michele (ed.) [Trieste Univ. Ospedale di Cattinara (Italy). Dept. Radiology

    2008-07-01

    This book provides a comprehensive reference and practical guide on the application of US to penile diseases and conditions. After introductory chapters on technical requirements and penile anatomy, subsequent chapters offer a systematic overview of the diverse applications of color Doppler US. The topics covered include erectile dysfunction, Peyronie's disease, priapism, trauma, tumors, the postoperative penis, inflammation, and fibrosis. Each topic is introduced by a clinical overview with the purpose of clarifying the problems and elucidating what the urologist may expect from color Doppler US. Thereafter, performance of the US study is explained and the pathological anatomy reviewed. High-quality images obtained with high-end US equipment are included. Each chapter also contains a section on the diagnostic information provided by other imaging modalities, and in particular MRI. (orig.)

  9. Determination of intestinal viability by Doppler ultrasonography in venous infarction.

    Science.gov (United States)

    Cooperman, M; Martin, E W; Carey, L C

    1980-01-01

    The accuracy of Doppler ultrasound in predicting the viability of ischemic intestine secondary to venous obstruction was assessed. Twenty loops of ischemic intestine were created in dogs by temporarily obstructing venous return from the bowel. Doppler arterial flow signals within the intestine quickly disappeared following venous occlusion. In ten segments, arterial signals promptly returned following release of venous occlusion. Nine of these ten segments were viable at reoperation 24 hours later. In ten segments, no arterial signals could be detected following release of venous occlusion, and only one segment proved to be viable. Doppler ultrasound findings were far more accurate in distinguishing between viable and nonviable intestine thatn were clinical guides to intestinal viability. PMID:7352777

  10. Effectiveness of Pulse Oximetry Versus Doppler for Tourniquet Monitoring.

    Science.gov (United States)

    Wall, Piper L; Buising, Charisse M; Grulke, Lisa; Troester, Alexander; Bianchina, Nicholas; White, Shannon; Freymark, Rosemarie; Hassan, Ali; Hopkins, James W; Renner, Catherine Hackett; Sahr, Sheryl M

    Pulse oximeters are common and include arterial pulse detection as part of their methodology. The authors investigated the possible usefulness of pulse oximeters for monitoring extremity tourniquet arterial occlusion. Tactical Ratcheting Medical Tourniquets were tightened to the least Doppler-determined occluding pressure at mid-thigh or mid-arm locations on one limb at a time on all four limbs of 15 volunteers. A randomized block design was used to determine the placement locations of three pulse oximeter sensors on the relevant digits. The times and pressures of pulsatile signal absences and returns were recorded for 200 seconds, with the tourniquet being tightened only when the Doppler ultrasound and all three pulse oximeters had pulsatile signals present (pulsatile waveform traces for the pulse oximeters). From the first Doppler signal absence to tourniquet release, toe-located pulse oximeters missed Doppler signal presence 41% to 50% of the times (discrete 1-second intervals) and missed 39% to 49% of the pressure points (discrete 1mmHg intervals); fingerlocated pulse oximeters had miss rates of 11% to 15% of the times and 13% to 19% of the pressure points. On toes, the pulse oximeter ranges of sensitivity and specificity for Doppler pulse detection were 71% to 90% and 44% to 51%, and on fingers, the respective ranges were 65% to 77% and 78% to 83%. Use of a pulse oximeter to monitor limb tourniquet effectiveness will result in some instances of an undetected weak arterial pulse being present. If a pulse oximeter waveform is obtained from a location distal to a tourniquet, the tourniquet should be tightened. If a pulsatile waveform is not detected, vigilance should be maintained. 2017.

  11. The Doppler paradigm and the APEX-EPOS-ORANGE quandary

    International Nuclear Information System (INIS)

    Griffin, J.J.

    1995-01-01

    The experimental detection of the sharp lines of the (e + e - ) Puzzle is viewed as a struggle against Doppler broadening. Gedanken experiments which are realistic in zeroth order of detail are analyzed to show that the ORANGE and EPOS/I geometries select narrower slices of a Doppler broadened line than spherically inclusive (APEX and EPOS/II -like) apparati. Roughly speaking, the latter require event-by-event Doppler reconstruction simply to regain an even footing with the former. This suggests that APEX' or EPOS/II's coincident pair distributions must be statistically superior to those of EPOS/I or ORANGE in order to support a comparable inference about sharp structure. Under such circumstances, independent alternative data is invaluable. Therefore, a corroboration of Sakai's 330.1 keV ( + or e - bombardments of U and Th targets could prove crucial

  12. Leukokoria in childhood: differential diagnosis using ultrasonography, computed tomography, and magnetic resonance imaging; Leucocoria na infancia: diagnostico diferencial por ultra-sonografia, tomografia computadorizada e ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Montandon Junior, Marcelo Eustaquio; Montandon, Cristiano [Colegio Brasileiro de Radiologia e Diagnostico por Imagem (CBR), Sao Paulo, SP (Brazil)]. E-mail: marmontandon@hotmail.com; Figueiredo, Sizenildo da Silva; Ribeiro, Flavia Aparecida de Souza; Nobrega, Bruno Barcelos da; Lobo, Leonardo Valadares Barbosa; Teixeira, Kim-Ir-Sen Santos [Goias Univ., Goiania (Brazil). Hospital das Clinicas. Servico de Diagnostico por Imagem e Anatomia Patologica; Jacob, Beatriz Mahmud [Goias Univ., Goiania (Brazil). Faculdade de Medicina. Radiologia e Diagnostico por Imagem

    2004-04-01

    Leukokoria is an abnormal pupillary reflex most commonly seen in children that usually results from an intra-ocular abnormality. The evaluation of a child with leukokoria should be performed particularly to rule out a retinoblastoma (the cause of leukokoria in half of the cases). The authors present the main clinical and imaging features for the diagnosis of the most common causes of leukokoria. (author)

  13. Doppler reactivity uncertainties and their effect upon a hypothetical LOF accident

    International Nuclear Information System (INIS)

    Malloy, D.J.

    1976-01-01

    The statistical uncertainties and the major methodological errors which contribute to the Doppler feedback uncertainty were reviewed and investigated. Improved estimates for the magnitudes of each type of uncertainty were established. The generally applied reactivity feedback methodology has been extended by explicitly treating the coupling effect which exists between the various feedback components. The improved methodology was specifically applied to the coupling of Doppler and sodium void reactivities. In addition, the description of the temperature dependence of the Doppler feedback has been improved by the use of a two-constant formula on a global and regional basis. Feedback and coupling coefficients are presented as a first comparison of the improved and the currently applied methods. Further, the energy release which results from hypothetical disassembly accidents was simulated with a special response surface in the parametric safety evaluation code PARSEC. The impact of the improved feedback methodology and of Doppler coefficient uncertainties was illustrated by the usual parametric relationship between available work-energy and the Doppler coefficient. The work-energy was calculated with the VENUS-II disassembly code and was represented as a response surface in PARSEC. Additionally, the probability distribution for available work-energy, which results from the statistical uncertainty of the Doppler coefficient, was calculated for the current and the improved feedback methodology. The improved feedback description yielded about a 16 percent higher average value for the work-energy. A substantially larger increase is found on the high-yield end of the spectrum: the probability for work-energy above 500 MJ was increased by about a factor of ten

  14. Reinforced Ultra-Tightly Coupled GPS/INS System for Challenging Environment

    Directory of Open Access Journals (Sweden)

    Xueyun Wang

    2014-01-01

    Full Text Available Among all integration levels currently available for Global Positioning System (GPS and Inertial Navigation System (INS Integrated System, ultra-tightly coupled (UTC GPS/INS system is the best choice for accurate and reliable navigation. Nevertheless the performance of UTC GPS/INS system degrades in challenging environments, such as jamming, changing noise of GPS signals, and high dynamic maneuvers. When low-end Inertial Measurement Units (IMUs based on MEMS sensors are employed, the performance degradation will be more severe. To solve this problem, a reinforced UTC GPS/INS system is proposed. Two techniques are adopted to deal with jamming and high dynamics. Firstly, adaptive integration Kalman filter (IKF based on fuzzy logics is developed to reinforce the antijamming ability. The parameters of membership functions (MFs are adjusted and optimized through self-developed neutral network. Secondly, a Doppler frequency error estimator based on Kalman filter is designed to improve the navigation performance under high dynamics. A complete simulation platform is established to evaluate the reinforced system. Results demonstrate that the proposed system architecture significantly improves navigation performance in challenging environments and it is a more advanced solution to accurate and reliable navigation than traditional UTC GPS/INS system.

  15. The chemistry of ultra-low concentrations

    International Nuclear Information System (INIS)

    Vertes, Attila; Kiss, Istvan

    1987-01-01

    Methods for the separation and enrichment of radionuclides in the ultra-low concentration range (coprecipitation, adsorption of radioactive substances on crystals) are disscussed in this chapter of the textbook. The properties and behaviour of ultra-dilute solutions, radiocolloids and the electrochemistry of ultra-dilute solution are also overviewed

  16. Biomicroscopia ultrasónica en pacientes operados de catarata traumática Ultrasound biomicroscopy used in patients operated from trauma cataract

    Directory of Open Access Journals (Sweden)

    Yanay Ramos Pereira

    2009-06-01

    Full Text Available OBJETIVO: Caracterizar a los pacientes operados de catarata traumática mediante su evaluación con biomicroscopia ultrasónica. MÉTODOS: Se realizó un estudio observacional, descriptivo, longitudinal y prospectivo en el servicio de microcirugía del Instituto Cubano de Oftalmología "Ramón Pando Ferrer", en el período comprendido entre enero de 2006 a enero de 2007. La muestra la conformaron 72 pacientes quienes recibieron tratamiento quirúrgico por diferentes técnicas con implante de lente intraocular. RESULTADOS: El 72,2 % fueron del sexo masculino y prevaleció el grupo de edad entre 40 y 49 años. La subluxación del cristalino estuvo presente en el 16,7 %. El 68,1 % presentó una amplitud de la cámara anterior normal independientemente del tipo de trauma. Los hallazgos más frecuentes por Biomicroscopía Ultrasónica fueron: el leucoma corneal, la desinserción zonular y la ruptura de cápsula posterior. Presentaron el mayor porcentaje de buena agudeza visual con corrección posoperatoria y sin ella los pacientes con lente intraocular en saco, localización más frecuente por biomicroscopia ultrasónica. Predominó la ruptura de las fibras zonulares por temporal. CONCLUSIONES: La biomicroscopia ultrasónica (BMU es un medio diagnóstico de gran importancia para la detección de alteraciones del segmento anterior en pacientes operados de catarata traumática.OBJECTIVE: To characterize the patients operated from trauma cataract through their evaluation with ultrasound biomicroscopy. METHODS: A longitudinal, prospective, observational and descriptive study was conducted in the Microsurgery Service of "Ramón Pando Ferrer" Cuban Institute of Ophthalmology from January 2006 to January 2007. The sample was made up of 72 patients who had been surgically treated using different techniques for intraocular lens implant. RESULTS: Male sex was 72.2 % and the prevailing age group was 40 to 49 years. Crystalline subluxation was found in 16.7 % of

  17. Applications of Doppler-free saturation spectroscopy for edge physics studies (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Martin, E. H., E-mail: martineh@ornl.gov; Caughman, J. B. O.; Isler, R. C.; Bell, G. L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Zafar, A. [Department of Nuclear Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2016-11-15

    Doppler-free saturation spectroscopy provides a very powerful method to obtain detailed information about the electronic structure of the atom through measurement of the spectral line profile. This is achieved through a significant decrease in the Doppler broadening and essentially an elimination of the instrument broadening inherent to passive spectroscopic techniques. In this paper we present the technique and associated physics of Doppler-free saturation spectroscopy in addition to how one selects the appropriate transition. Simulations of H{sub δ} spectra are presented to illustrate the increased sensitivity to both electric field and electron density measurements.

  18. The role of Doppler ultrasonography in the evaluation of the renal function

    International Nuclear Information System (INIS)

    Krasteva, R.; Kiperova, B.; Andreev, E.; Kostadinova, I.; Petrov, T.; Hadjidekov, V.; Simeonova, A.

    2008-01-01

    The purpose of the study was to evaluate Doppler ultrasonography in the detection of the renal function. Sixty six patients with unilateral kidney changes were enrolled in this prospective study. 16 had hypoplastic kidney, 24 had hypofunctioned kidney and 26 had afunctioned kidney. 15 healthy potential donors were controls. A dynamic renal scintigraphy was performed with 74-111 MBq 99mTc-MAG3. The Color, Pulsed and Power Doppler were performed. The Vp and δVp derived from the spectrum of the segmental arteries were measured during Pulsed Doppler examination. There are not any difference between kidneys of health and hypoplastic kidneys on color and Power Doppler. The hypofunctioning kidneys had reduced blood flow and afunctioning kidneys had markedly reduced blood flow. The Vp of donors (48.8±7.6) and Vp of hypoplastic kidneys (49.9±4.8) were significantly higher compared to Vp of hypofunctioning kidneys (31.6±10.0) and to Vp of afunctioning kidneys (26.6±9.1), (p 14.5 cm/s in 93%, and from hypofunctioning kidney by delta Vp>10.5 cm/s in 87%. The Doppler ultrasonography is very useful in the evaluation of renal function. The changes of the Doppler parameters accurately marked the loss of function which can not be detected by elevation of the creatinine level. (authors)

  19. Doppler derived gradient of ST Jude Mechanical Prosthesis, early postoperative assessment

    International Nuclear Information System (INIS)

    Shaikh, A.H.; Hanif, B.; Adil, A.; Hashimi, S.; Qazi, H.A.; Mujtaba, I.

    2010-01-01

    Objective: To determine the doppler derived mean gradients of St Jude mechanical prosthesis in early postoperative period in patients undergoing valve replacement at a tertiary care cardiac centre. Methods: Medical records of 190 consecutive patients who underwent 233 mitral, aortic or dual (mitral and aortic) valve replacement by St Jude bileaflet mechanical prosthesis at Tabba Heart Institute, between March 2006 to December 2008 were reviewed. Doppler derived mean gradients were assessed predischarge and recorded. Results: There were 98 (51.5%) males and 92 (48.5%) females in the study cohort. The mean age was 40 +- 14 years. Of the total, 101 (53%) had mitral, 46 (24.2%) had aortic and 43 (22.6%) patients had dual valve replacement. Doppler derived mean gradient was assessed across 144 mitral and 89 aortic St Jude mechanical prosthesis. Doppler derived mean gradient for St Jude mitral prosthesis was 3.5 mm Hg and for St Jude aortic prosthesis was 10.2 mm Hg. Conclusions: The study determines baseline gradients across mitral and aortic St Jude mechanical prosthesis in our population. These can be used as reference gradients to assess St Jude prosthetic valve function in patients who did not have early postoperative doppler assessment. (author)

  20. Moldagem por compressão a frio do polietileno de ultra alto peso molecular. Parte 1: influência do tamanho, distribuição e morfologia da partícula na densidade a verde Cold compression molding of ultra high molecular weight polyethylene. Part 1: influence of the size, distribution and morphology of particles on the green density

    Directory of Open Access Journals (Sweden)

    Bernadete A. Bittencourt

    2009-01-01

    Full Text Available Neste trabalho foram investigadas as características de amostras de pó de polietileno de ultra alto peso molecular (PEUAPM, tais como porosidade, morfologia, tamanho médio e distribuição de partícula, que são importantes na moldagem por compressão a frio. Também foi avaliada a influência dessas características na densidade a verde de pré-formas. As amostras dos pós foram caracterizadas por calorimetria diferencial de varredura (DSC, análise granulométrica, absorção de óleo, área superficial, porosimetria de mercúrio, fluidez do pó, densidade de compactação, densidade aparente e microscopia eletrônica de varredura (MEV. Através das técnicas de caracterização estudadas ficou evidenciado que as características da partícula citadas anteriormente, assim como o parâmetro de densificação (DP, que é função direta da porosidade interparticular, favorecem a densidade a verde relativa (DVR e consequentemente a tensão de resistência à flexão (TRF.In this paper an investigation was made of the characteristics of Ultra High Molecular Weight Polyethylene (UHMWPE powder samples, including porosity, particles average size, size distribution and morphology, which are important in cold compression molding. The influence of these characteristics on the green density of molded pre-shapes was also investigated. The UHMWPE powder samples were characterized by Differential Scanning Calorimetry (DSC, granulometric analysis, oil absorption, surface area, mercury porosity, density compaction, apparent density and Scanning Electron Microscopy (SEM. The characterization techniques used demonstrate that the UHMWPE particles characteristics cited above as well as the densification parameter (DP, which is a direct function of the interparticles porosity, affect the relative green density (RGD and hence, the flexural tensile strength (FTS.

  1. Associação da Vaginose Bacteriana com o Parto Prematuro Espontâneo Association of Bacterial Vaginosis with Spontaneous Preterm Delivery

    Directory of Open Access Journals (Sweden)

    Mário Henrique Burlacchini de Carvalho

    2001-09-01

    Full Text Available Objetivo: relacionar a presença de vaginose bacteriana em gestantes com a ocorrência de parto prematuro espontâneo. Método: foram estudadas 611 gestantes do serviço pré-natal da Clínica Obstétrica do HCFMUSP. Foram incluídas gestantes com idade gestacional confirmada por ultra-sonografia no primeiro trimestre de gestação ou duas ultra-sonografias até a 20ª semana quando havia discordância da idade gestacional no primeiro exame. Os partos prematuros eletivos foram excluídos. A pesquisa da vaginose foi realizada na 23ª ou 24ª semana de gestação por meio da técnica de coloração de Gram. O pH vaginal foi pesquisado utilizando-se fita de pH Universal 0-14 produzida pela Merck. O conteúdo vaginal foi coletado com a paciente em posição ginecológica, utilizando-se espéculo não-lubrificado. O pH foi medido na parede lateral da vagina e o conteúdo para Gram foi coletado do fundo de saco vaginal utilizando-se de cotonete estéril. Resultado: das 611 gestantes envolvidas inicialmente no estudo, foram obtidos os resultados do parto em 541. A vaginose bacteriana foi diagnosticada por bacterioscopia em 19% dos casos. No grupo de gestantes com vaginose, 9,7% (10/103 evoluíram com parto prematuro, contra apenas 3,2% (14/438 no grupo negativo (p=0,008. A sensibilidade da bacterioscopia positiva para vaginose bacteriana para predição do parto prematuro foi de 41,7%, a especificidade de 82%, a acurácia de 80,2%, com taxa de falso-positivos de 18% e risco relativo de 1,8. Conclusão: a vaginose bacteriana diagnosticada pelo Gram do conteúdo vaginal representa fator de risco para o parto prematuro, com risco relativo de 1,8.Purpose: to evaluate the relationship between bacterial vaginosis (BV and spontaneous preterm delivery. Method: a total of 611 pregnant women from the general antenatal clinic of the "Clínica Obstétrica do Hospital das Clínicas da Universidade de São Paulo" were enrolled in this study. All pregnancies were

  2. Analysis of placenta vascularization in patients with uterine altered artery Doppler flow velocity exams.

    Science.gov (United States)

    Gilio, Daniel Bruno; Miranda Corrêa, Rosana Rosa; Souza de Oliveira Guimarães, Camila; Peres, Luiz Cesar; Marques Salge, Ana Karina; Cavellani, Camila Lourencini; de Paula Antunes Teixeira, Vicente; Costa da Cunha Castro, Eumenia

    2009-08-01

    One of the frequent questions in obstetric practice is to determine placental vascular changes that may account for abnormal Doppler flow velocity alterations in maternal uterine vessels from women and fetuses without pregnancy pathology. A retrospective morphometric study was realized using 27 placentas from patients submitted for Doppler flow velocity exam during pregnancy. The placentas were morphologically examined using hematoxylin-eosin staining. Measurements of villi were made with the use of a video camera coupled to a common light microscope and a computer with automatic image analyzing software. Of the 27 placentas, 13 (48%) were of patients showing unaltered Doppler and 14 (52%) showing altered Doppler. The number of stem villi vessels was significantly larger in the placentas of patients with Doppler exam alterations (P = 0.003). This group also presented greater stem villi vessel thickness, although without significant difference. The number of intermediary and terminal villi vessels was greater in the placentas of patients with altered Doppler exams (P < 0.001), and a greater terminal villi area was observed in these cases (P < 0.001). The morphological proof that uterine artery Doppler flow velocity exam alterations are associated with placental vascular alterations demonstrates the importance of this exam during prenatal care, even in the absence of maternal-fetal alterations.

  3. Modeling and processing of laser Doppler reactive hyperaemia signals

    Science.gov (United States)

    Humeau, Anne; Saumet, Jean-Louis; L'Huiller, Jean-Pierre

    2003-07-01

    Laser Doppler flowmetry is a non-invasive method used in the medical domain to monitor the microvascular blood cell perfusion through tissue. Most commercial laser Doppler flowmeters use an algorithm calculating the first moment of the power spectral density to give the perfusion value. Many clinical applications measure the perfusion after a vascular provocation such as a vascular occlusion. The response obtained is then called reactive hyperaemia. Target pathologies include diabetes, hypertension and peripheral arterial occlusive diseases. In order to have a deeper knowledge on reactive hyperaemia acquired by the laser Doppler technique, the present work first proposes two models (one analytical and one numerical) of the observed phenomenon. Then, a study on the multiple scattering between photons and red blood cells occurring during reactive hyperaemia is carried out. Finally, a signal processing that improves the diagnosis of peripheral arterial occlusive diseases is presented.

  4. Tamizaje y prevención de pre-eclampsia guiado por Doppler de arterias uterinas: revisión sistemática de la literatura

    OpenAIRE

    Sáez O, Nicolás; Carvajal C, Jorge

    2012-01-01

    Antecedentes: La pre-eclampsia (PE) es una enfermedad grave asociada al embarazo con una prevalencia de ~3%. La identificación de las mujeres en riesgo podría mejorar el resultado materno y perinatal. La estimación de riesgo individual de PE permitiría ofrecer un tratamiento preventivo para ésta [ej: aspirina (AAS)]. Se ha descrito el Doppler de arterias uterinas (DAUt) en primer y segundo trimestre como un método de tamizaje de PE. Objetivo: Recopilar la evidencia disponible sobre el uso del...

  5. Explanation of the Inverse Doppler Effect Observed in Nonlinear Transmission Lines

    International Nuclear Information System (INIS)

    Kozyrev, Alexander B.; Weide, Daniel W. van der

    2005-01-01

    The theory of the inverse Doppler effect recently observed in magnetic nonlinear transmission lines is developed. We explain the crucial role of the backward spatial harmonic in the occurrence of an inverse Doppler effect and draw analogies of the magnetic nonlinear transmission line to the backward wave oscillator

  6. Research on Fast-Doppler-Broadening of neutron cross sections

    International Nuclear Information System (INIS)

    Li, S.; Wang, K.; Yu, G.

    2012-01-01

    A Fast-Doppler-Broadening method is developed in this work to broaden Continuous Energy neutron cross-sections for Monte Carlo calculations. Gauss integration algorithm and parallel computing are implemented in this method, which is unprecedented in the history of cross section processing. Compared to the traditional code (NJOY, SIGMA1, etc.), the new Fast-Doppler-Broadening method shows a remarkable speedup with keeping accuracy. The purpose of using Gauss integration is to avoid complex derivation of traditional broadening formula and heavy load of computing complementary error function that slows down the Doppler broadening process. The OpenMP environment is utilized in parallel computing which can take full advantage of modern multi-processor computers. Combination of the two can reduce processing time of main actinides (such as 238 U, 235 U) to an order of magnitude of 1∼2 seconds. This new method is fast enough to be applied to Online Doppler broadening. It can be combined or coupled with Monte Carlo transport code to solve temperature dependent problems and neutronics-thermal hydraulics coupled scheme which is a big challenge for the conventional NJOY-MCNP system. Examples are shown to determine the efficiency and relative errors compared with the NJOY results. A Godiva Benchmark is also used in order to test the ACE libraries produced by the new method. (authors)

  7. Influence of the development phase of the dominant follicle on the superovulatory response in Nelore heifers

    Directory of Open Access Journals (Sweden)

    Mayra Elena Ortiz D'’Avila Assumpção

    1999-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência do folículo dominante nas fases de crescimento, estática e de regressão sobre a resposta superovulatória em 18 ciclos estrais de 9 novilhas da raça Nelore. Avaliaram-se os ovários entre o dia 6 e o dia 10 do ciclo estral pela técnica de ultra-sonografia, medindo-se o diâmetro do maior folículo e contando-se o número de folículos subordinados. Os animais foram superovulados com 400 ou 500 UI de FSH/LH, iniciando-se no dia 10 do ciclo estral, em subdoses decrescentes, por 4 dias consecutivos. Aplicou-se PGF2alfa concomitante com a quinta subdose de FSH/LH e realizaram-se inseminações artificiais às l2 horas e às 24 horas após o início dos sintomas de estro. Os embriões foram colhidos no dia 6,5 após a primeira inseminação artificial, obtendo-se 3,00; 3,83 e 10,17 embriões, respectivamente, nas fases de crescimento, estática e regressão. Observaram-se melhores resultados quanto ao número de embriões quando o folículo dominante se encontrava em fase de regressão.

  8. Macroscopic effects in electromagnetically-induced transparency in a Doppler-broadened system

    International Nuclear Information System (INIS)

    Pei Li-Ya; Qu Yi-Zhi; Niu Jin-Yan; Wang Ru-Quan; Wu Ling-An; Fu Pan-Ming; Zuo Zhan-Chun

    2015-01-01

    We study the electromagnetically-induced transparency (EIT) in a Doppler-broadened cascaded three-level system. We decompose the susceptibility responsible for the EIT resonance into a linear and a nonlinear part, and the EIT resonance reflects mainly the characteristics of the nonlinear susceptibility. It is found that the macroscopic polarization interference effect plays a crucial role in determining the EIT resonance spectrum. To obtain a Doppler-free spectrum there must be polarization interference between atoms of different velocities. A dressed-state model, which analyzes the velocities at which the atoms are in resonance with the dressed states through Doppler frequency shifting, is employed to explain the results. (paper)

  9. Testing the relativistic Doppler boost hypothesis for supermassive black hole binary candidates

    Science.gov (United States)

    Charisi, Maria; Haiman, Zoltán; Schiminovich, David; D'Orazio, Daniel J.

    2018-06-01

    Supermassive black hole binaries (SMBHBs) should be common in galactic nuclei as a result of frequent galaxy mergers. Recently, a large sample of sub-parsec SMBHB candidates was identified as bright periodically variable quasars in optical surveys. If the observed periodicity corresponds to the redshifted binary orbital period, the inferred orbital velocities are relativistic (v/c ≈ 0.1). The optical and ultraviolet (UV) luminosities are expected to arise from gas bound to the individual BHs, and would be modulated by the relativistic Doppler effect. The optical and UV light curves should vary in tandem with relative amplitudes which depend on the respective spectral slopes. We constructed a control sample of 42 quasars with aperiodic variability, to test whether this Doppler colour signature can be distinguished from intrinsic chromatic variability. We found that the Doppler signature can arise by chance in ˜20 per cent (˜37 per cent) of quasars in the nUV (fUV) band. These probabilities reflect the limited quality of the control sample and represent upper limits on how frequently quasars mimic the Doppler brightness+colour variations. We performed separate tests on the periodic quasar candidates, and found that for the majority, the Doppler boost hypothesis requires an unusually steep UV spectrum or an unexpectedly large BH mass and orbital velocity. We conclude that at most approximately one-third of these periodic candidates can harbor Doppler-modulated SMBHBs.

  10. Aortic isthmus Doppler velocimetry: role in assessment of preterm fetal growth restriction.

    LENUS (Irish Health Repository)

    Kennelly, M M

    2012-02-01

    Intrauterine fetal growth restriction (IUGR) is an important pregnancy complication associated with significant adverse clinical outcome, stillbirth, perinatal morbidity and cerebral palsy. To date, no uniformly accepted management protocol of Doppler surveillance that reduces mortality and cognitive morbidity has emerged. Aortic isthmus (AoI) evaluation has been proposed as a potential monitoring tool for IUGR fetuses. In this review, the current knowledge of the relationship between AoI Doppler velocimetry and preterm fetal growth restriction is reviewed. Relevant technical aspects and reproducibility data are reviewed as we discuss AoI Doppler and its place within the existing repertoire of Doppler assessments in placental insufficiency. The AoI is a link between the right and left ventricles which perfuse the lower and upper body, respectively. The clinical use of AoI waveforms for monitoring fetal deterioration in IUGR has been limited, but preliminary work suggests that abnormal AoI impedance indices are an intermediate step between placental insufficiency-hypoxemia and cardiac decompensation. Further prospective studies correlating AoI indices with arterial and venous Doppler indices and perinatal outcome are required before encorporating this index into clinical practice.

  11. Doppler-ultrasonographic finding of air in the portal vein: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ki Soon; Lee, Kwan Sup; Lee, Yul; Chung, Soo Young; Bae, Sang Hoon [College of Medicine, Hallym University, Seoul (Korea, Republic of)

    1994-03-15

    Classically air in the portal vein has been detected on plain radiography, but computed tomography and ultrasonography have been shown to be more sensitive. We report a case of air in the PV in a 10-day-old infant with pneumatosis intestinalis with its ultrasonographic and Doppler findings. The patient was a 10-day-old infant born by cesarean section at 41 weeks. Simple abdomen film revealed branching pattern of radiolucent air shadows within in contour of liver, gas distention of bowel loops and thickenod bowel walls with lincar intraluminal air shadows in abdomen, suggesting necrotizing enterocolitis. So we performed Doppler ultrasonography. Ultrasonography showed branching pattern of hyperechogenic dots and along the lumen of left portal vein. The color Doppler study revealed an aliasing duo to increased velocity and whirling pattern of blood flow, and the Duplex Doppler spectral display showed sharp, vertical bidirectional spikes by air in portal vein. Air in the portal vein can be easily diagnosed by the following signs: hyperechogenic dots in the portal vein on ultrasonography and vertical, sharp bidirectional spikes superimposed on the usual Doppler tracing of the portal vein on Duplex ultrasonography.

  12. Doppler-ultrasonographic finding of air in the portal vein: a case report

    International Nuclear Information System (INIS)

    Park, Ki Soon; Lee, Kwan Sup; Lee, Yul; Chung, Soo Young; Bae, Sang Hoon

    1994-01-01

    Classically air in the portal vein has been detected on plain radiography, but computed tomography and ultrasonography have been shown to be more sensitive. We report a case of air in the PV in a 10-day-old infant with pneumatosis intestinalis with its ultrasonographic and Doppler findings. The patient was a 10-day-old infant born by cesarean section at 41 weeks. Simple abdomen film revealed branching pattern of radiolucent air shadows within in contour of liver, gas distention of bowel loops and thickenod bowel walls with lincar intraluminal air shadows in abdomen, suggesting necrotizing enterocolitis. So we performed Doppler ultrasonography. Ultrasonography showed branching pattern of hyperechogenic dots and along the lumen of left portal vein. The color Doppler study revealed an aliasing duo to increased velocity and whirling pattern of blood flow, and the Duplex Doppler spectral display showed sharp, vertical bidirectional spikes by air in portal vein. Air in the portal vein can be easily diagnosed by the following signs: hyperechogenic dots in the portal vein on ultrasonography and vertical, sharp bidirectional spikes superimposed on the usual Doppler tracing of the portal vein on Duplex ultrasonography

  13. Determinação do módulo de elasticidade da madeira juvenil e adulta de Pinus taeda por ultra-som Determination of the modulus of elasticity of juvenile and mature wood of Pinus taeda L.with ultrasonic method

    Directory of Open Access Journals (Sweden)

    Adriano W. Ballarin

    2005-04-01

    Full Text Available A madeira de Pinus sp. tem utilização crescente na indústria madeireira brasileira. O decréscimo constante do suprimento de árvores adultas com grandes diâmetros, provenientes de florestas naturais, tornou comum a produção de madeira em ciclos curtos, com grande proporção de madeira juvenil. Resultados de diversas pesquisas têm reportado que o módulo de elasticidade e a resistência a diferentes solicitações mecânicas são seriamente afetados pela presença de madeira juvenil. Este trabalho teve por objetivo determinar o módulo de elasticidade da madeira juvenil e adulta de Pinus taeda L. a partir da constante dinâmica C LL, obtida em ensaios não-destrutivos de ultra-som. A madeira de P. taeda era originária de plantios da Estação Experimental de Itapeva - SP, sendo amostrados seis indivíduos arbóreos com 34 anos de idade. Os corpos-de-prova (4 cm x 4 cm x 45 cm foram obtidos separadamente das regiões de madeira juvenil e adulta da prancha central, previamente submetida à secagem industrial (umidade final de 12%, para a determinação da constante dinâmica por meio de ensaios de ultra-som. Para avaliar a sensibilidade do método do ultra-som, os corpos-de-prova foram ensaiados destrutivamente à compressão paralela. Os resultados mostraram boa sensibilidade do método do ultra-som (R² » 0,90 na avaliação desse parâmetro mecânico da madeira juvenil e adulta.Pinus sp. wood has an increasing importance on supplying brazilian wood industry. The diminution of adult and large diameter trees supply deriving from natural tropical forests, became usual the production of wood on short rotation plantation, with considerable proportion of juvenil wood. Results from several researches have been demonstrated that MOE and mechanical strength are strongly affected by juvenile wood occurrence. This research was developed with the main objective of correlating dynamic modulus of elasticity (non-destructive ultrasound tests and MOE

  14. Ultrasonographic investigation of the Achilles tendon in elite badminton players using color Doppler.

    Science.gov (United States)

    Boesen, Morten Ilum; Boesen, Anders; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren

    2006-12-01

    The most frequent injuries in badminton players are in the lower extremities, especially in the Achilles tendon. The game of badminton may be related to abnormal intratendinous flow in the Achilles tendon as detected by color Doppler ultrasound. To a certain extent, this blood flow might be physiological, especially when examined after match. Cohort study (prevalence); Level of evidence, 3. Seventy-two elite badminton players were interviewed regarding Achilles tendon pain (achillodynia) in the preceding 3 years. Color Doppler was used to examine the tendons of 64 players before their matches and 46 players after their matches. Intratendinous color Doppler flow was graded from 0 to 4. The Achilles tendon was divided into dominant (eg, right side for right-handed players and vice versa) and nondominant side and classified as midtendon, preinsertional, and calcaneal areas. Of 72 players, 26 had experienced achillodynia in 34 tendons, 18 on the dominant side and 16 on the nondominant side. In 62% of the players with achillodynia, the problems had begun slowly, and the median duration of symptoms was 4 months (range, 0-36 months). Thirty-five percent had ongoing pain in their tendons for a median duration of 12 months (range, 0-12 months). Achillodynia was not associated with the self-reported training load or with sex, age, weight, singles or doubles players, or racket side. Forty-six players were scanned before and after match. At baseline, color Doppler flow was present in the majority of players, and only 7 (16%) players had no color Doppler flow in either tendon. After match, all players had some color Doppler flow in 1 or both tendons. Achillodynia and color Doppler flow were related in the nondominant Achilles tendon (chi-square, P = .008). The grades of Doppler flow also increased significantly after match in the preinsertional area in both the nondominant (P = .0002) and dominant (P = .005) side tendons. A large proportion of the players had experienced

  15. Effect of Doppler flow meter position on discharge measurement in surcharged manholes.

    Science.gov (United States)

    Yang, Haoming; Zhu, David Z; Liu, Yanchen

    2018-02-01

    Determining the proper installation location of flow meters is important for accurate measurement of discharge in sewer systems. In this study, flow field and flow regimes in two types of manholes under surcharged flow were investigated using a commercial computational fluid dynamics (CFD) code. The error in measuring the flow discharge using a Doppler flow meter (based on the velocity in a Doppler beam) was then estimated. The values of the corrective coefficient were obtained for the Doppler flow meter at different locations under various conditions. Suggestions for selecting installation positions are provided.

  16. Correlation between Doppler flow patterns in growth-restricted fetuses and neonatal circulation

    NARCIS (Netherlands)

    Tanis, J. C.; Boelen, M. R.; Schmitz, D. M.; Casarella, L.; van der Laan, M. E.; Bos, A. F.; Bilardo, C. M.

    Objectives To investigate whether prenatal Doppler parameters in growth-restricted fetuses are correlated with neonatal circulatory changes. Methods In 43 cases of suspected fetal growth restriction (FGR), serial Doppler measurements of umbilical artery (UA) and middle cerebral artery (MCA)

  17. Role of Doppler US and MRI in diagnosis of placenta accreta ...

    African Journals Online (AJOL)

    The aim of this work is to evaluate the role of Doppler US and MRI in the diagnosis of placenta accreta. Patients and methods: During period between 2012 to 2013, 120 pregnant patients with previous cesarean section were investigated by ultrasound and Doppler and then in suspected cases MRI was obtained (10 cases).

  18. Ultra-orthodox Jewish Women Go to Work

    Directory of Open Access Journals (Sweden)

    Foscarini, Giorgia

    2014-12-01

    Full Text Available In the last three decades the ultra-orthodox community in Israel has experienced great changes in its internal social functioning. More specifically, these developments were linked to the education of ultra-orthodox women. Through an accurate review of the existing literature and a series of in-depth interviews with Israeli scholars, rabbis, educators and women of the ultra-orthodox community in Jerusalem, it was found that the introduction of new vocational and academic training tracks in women's education, is gradually changing the internal social structure of the ultra-orthodox family and community. The main consequence is expressed in a renegotiation of gender roles within the ultra-orthodox community and in a subversion of the traditional patriarchal framework. As a result of their participation in the labor market and in higher education institutions, women are more and more exposed to the Israeli secular culture, introducing in the traditional and segregated ultra-orthodox community customs typically modern, narrowing the gap between the ultra-orthodox community and the mainstream Israeli society.

  19. Ultra-short laser pulses. Petawatt and femtosecond

    International Nuclear Information System (INIS)

    Lemoine, P.

    1999-01-01

    This book deals with a series of new results obtained thanks to the use of ultra-short laser pulses. This branch of physics has made incredible progresses during the last 25 years. Ultra-short laser pulses offer the opportunity to explore the domain of ultra-high energies and of ultra-short duration events. Applications are various, from controlled nuclear fusion to eye surgery and to more familiar industrial applications such as electronics. (J.S.)

  20. Cálculo del poder de la lente intraocular mediante biometría ultrasónica

    Directory of Open Access Journals (Sweden)

    Yileika Elías García

    Full Text Available Objetivo: caracterizar el comportamiento del cálculo de la lente intraocular mediante biometría ultrasónica. Métodos: se realizó un estudio descriptivo y prospectivo, con un grupo de pacientes atendidos por el Servicio de Catarata del Centro Oftalmológico «Enrique Cabrera», que recibieron tratamiento quirúrgico por catarata con implante de lente intraocular, mediante técnica de Blumenthal. La muestra se conformó con 160 ojos y se estudiaron las variables: sorpresa refractiva, edad, longitud axial y promedio queratométrico según resultado refractivo, poder dióptrico de la lente y componente esférico según edad. Resultados: como resultados más sobresalientes, se obtuvo que el 78,7 % no presentó error en el cálculo de la lente, la mayoría de los pacientes tenían 60 años y más, predominó el rango de longitud axial entre 22 y 24,4 (67,5 %, el promedio queratométrico de 43 a 44,99 (64,3 %, el poder dióptrico del lente de + 20 a + 23 dioptrías (48,2 % y el componente esférico entre 0,00 y +/-1,00 dioptrías (78,8%. Conclusiones: se considera que la biometría ultrasónica resulta adecuada para el cálculo correcto del lente.

  1. Kan Doppler-ultralyd erstatte strain gauge til måling af systolisk ankelblodtryk?

    DEFF Research Database (Denmark)

    Sørensen, T L; Perner, A; Hansen, L

    1992-01-01

    Traditionally, strain gauge technique is used in Denmark to measure ankle blood pressure, a method requiring both time and well-trained personnel. In a study involving 90 limbs in 45 patients, this method was compared with ultrasonic technique using a portable 5 MHz Doppler. The reproducibility...... of Doppler ankle pressure measurement was similar to that found in strain gauge based studies. Two consecutive measurements may differ by 20 mmHg or in terms of ankle-brachial index by 0.15 before this is considered significant. No systematic variation was found between the two methods. Increasing...... difficulties were encountered with the Doppler technique at pressures below 50 mmHg. It is concluded that Doppler is a good alternative to strain gauge for measurement of ankle blood pressure....

  2. Transcranial Doppler Ultrasound in Peninsular Arab Patients With Sickle Cell Disease.

    Science.gov (United States)

    Adekile, Adekunle; Hassan, Meaad; Asbeutah, Akram; Al-Hinai, Mohamed; Trad, Omar; Farhan, Nayef

    2018-05-06

    Transcranial Doppler ultrasound is used to identify patients with sickle cell disease (SCD) at risk for stroke. We performed transcranial Doppler studies in patients from 4 countries in the Arabian Peninsula (Kuwait, Oman, Iraq, and United Arab Emirates) to document the prevalence of abnormal transcranial Doppler findings. The patients were recruited from outpatient clinics and studied in a steady state. Transcranial Doppler examinations were performed with standard equipment by experienced operators. The time-averaged maximum mean velocity (TAMMV) was documented in the arteries of the circle of Willis. The hemoglobin (Hb) genotype was confirmed, and the fetal Hb level and complete blood counts were determined. There were 415 patients in the study, aged 2 to 18 years (mean ± SD, 8.6 ± 3.5 years). None of the patients had an abnormal TAMMV (ie, > 200 cm/s), whereas only 13 (3.1%), all from Iraq, had conditional values (170-200 cm/s) in the right middle cerebral artery and 7 (1.7%) in the left middle cerebral artery. There were no consistent TAMMV differences among male and female patients or in patients with different Hb genotypes (sickle cell anemia, sickle cell β 0- thalassemia, and sickle D). The use of hydroxyurea was associated with a lower TAMMV, whereas a blood transfusion history had no influence. Total hemoglobin, reticulocyte count, serum bilirubin, and fetal Hb values showed varying degrees of association with the TAMMV in the different vessels. This study has demonstrated the rarity of abnormal transcranial Doppler findings among Peninsular Arab patients with SCD. The guidelines for transcranial Doppler screening in this population need further studies and recommendations. © 2018 by the American Institute of Ultrasound in Medicine.

  3. Doppler echocardiographic predictors of mortality in female rats after myocardial infarction.

    Science.gov (United States)

    Santos, Alexandra Alberta; Helber, Izzo; Flumignan, Ronald L G; Antonio, Ednei L; Carvalho, Antonio C; Paola, Angelo A; Tucci, Paulo J; Moises, Valdir A

    2009-03-01

    Doppler echocardiogram is useful for the evaluation of anatomical and functional changes in late myocardial infarction (MI) in rats. However, no studies have evaluated the prognostic value of echocardiographic parameters 1 week after MI. Doppler echocardiogram was performed in 84 female Wistar rats 1 week after MI to determine infarction size, left chambers dimensions, fractional area change (FAC) of the left ventricle (LV), mitral inflow and tissue Doppler, myocardial performance index (MPI), and signs of pulmonary hypertension. The 365-day follow-up showed 53.6% mortality rate. Nonsurvivors showed larger (P or=0.60 (RR 3.49, 95% CI, 1.80-6.76), LV systolic area >or=0.26 cm(2) (RR 4.38, 95% CI, 1.88-10.21), E/E' ratio >or=20.3 (RR 2.12, 95% CI, 1.15-4.34), and E/A ratio associated with FAC (RR 2.99, 95% CI, 1.44-6.18). Some diastolic and systolic Doppler echocardiographic parameters in rats may be able to predict late mortality risk after MI.

  4. Computer-assisted quantitative assessment of power Doppler US: effects of microbubble contrast agent in the differentiation of breast tumors

    International Nuclear Information System (INIS)

    Kettenbach, Joachim; Helbich, Thomas H.; Huber, Sabine; Zuna, Ivan; Dock, Wolfgang

    2005-01-01

    Rationale and objectives: To objectively quantify the effects of a microbubble contrast agent to differentiate breast tumors with power doppler ultrasound and to compare these results with color doppler ultrasound (CD US). Methods: In 47 patients a microbubble contrast agent was injected intravenously. Computer-assisted quantitative assessment of the color pixel density was performed to evaluate the increase in Doppler signals. Results were compared to previously published results of a color Doppler ultrasound study. Results: Peak color pixel density at contrast-enhanced power Doppler ultrasound was higher for carcinomas than for benign tumors (P < 0.03). Time to peak enhancement was shorter in carcinomas than in benign tumors (P < 0.01). For both parameters, diagnostic accuracy of power Doppler ultrasound was 69 and 78%, and for color Doppler ultrasound 62 and 76%, respectively. Conclusions: Quantitative assessment of contrast-enhanced power Doppler ultrasound showed significant differences in malignant and benign breast tumors. Diagnostic accuracy of contrast-enhanced power Doppler ultrasound was higher compared to color Doppler ultrasound

  5. Doppler effect measurement in FCA assemblies X-3 and XI-1

    International Nuclear Information System (INIS)

    Okajima, Shigeaki; Mukaiyama, Takehiko

    1984-05-01

    Doppler reactivity worths were measured in FCA assemblies X-3 (mock-up core for JOYO Mark II) and XI-1 (mock-up core for large scale LMFBR) for U-238 and stractural materials of core (iron, stainless steel and nickel). The sample oscillation technique was used to measure the Doppler effect when a sample is heated up to 800 0 C from room temperature. The analysis was made using the 70 group JFS-3-J2 data set, and compared with the measured results. For U-238 samples, the calculation underestimates Doppler effects by 10%, on the other hand for other samples, the agreement between calculated values and measured values is quite good. (author)

  6. Vesico-ureteral reflux: diagnosis and staging with voiding color doppler US Preliminary experience

    International Nuclear Information System (INIS)

    Farina, Renato; Arena, Carmela; Pennisi, Francesco; Di Benedetto, Vincenzo; Politi, Guido; Di Benedetto, Aurelio

    2000-01-01

    Introduction: The aim of this study is to assess the accuracy of a new US examination: 'voiding color Doppler US ' in the early diagnosis and staging of vesico-ureteral reflux (VUR). The contrast agent US was SH U 508A (Levovist, Schering, Berlin), which produces a chromatic accentuation of the signals picked up by the color Doppler US. Eighteen patients (10 females, eight males) were recruited for the study. In two patients a second examination was performed for follow-up after a VUR conservative therapy. All patients were taken under examination for the evaluation of possible VUR. In all patients the voiding color Doppler US was followed by voiding cystourethrography (VCUG) and the data obtained were compared. Materials and methods: A total of 18 patients aged between 3 months and 10 years, were recruited for the study. The results of the examination were the following: urinary tract infections, follow-up of VUR after conservative or surgical therapy, miscellaneous indications. Voiding color Doppler US was performed, followed by a VCUG. The voiding color Doppler US consists in the trans-catheter introduction of a contrast agent SHU 508 A (Levovist, Schering, Ag. Berlin) into the bladder and a subsequent test with the color Doppler US to show or exclude the presence of reflux into the ureters and/or into the pyelo-caliceal cavity of the kidneys. After the introduction of the contrast agent US the ultrasound scanning of the bladder, the ureters and the pyelo-caliceal cavity was performed to examine the reflux degree. The ultrasonographic investigations were perfomed with AU 590 asyncronus US (Esaote Biomedica, Genova) with a 3.5 MHz convex probe. Results: After the trans-catheter introduction of the contrast agent US, vesico-ureteral reflux occured in 13 patients (77.2%). The reflux degree was also measured by means of ultrasound and was later confirmed by VCUG. The mean times of each examination were as follows: initial US, 10 min; catheterization, 8 min; voiding

  7. Application of Energy Window Concept in Doppler Broadening of {sup 238}U Cross Section

    Energy Technology Data Exchange (ETDEWEB)

    Khassnov, Azamat; Choi, Soo Young; Lee, Deok Jung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2014-10-15

    Currently, the NJOY code is used for construction and Doppler broadening of microscopic cross sections. There exist several methods or formalisms to produce microscopic cross sections and there are also different methods of Doppler broadening. In this paper, Multi-Level Breit-Wigner (MLBW) formalism and the Psi method are used for generation and Doppler broadening of the resonance cross section. Accuracy of the energy window concept applied MLBW (EW MLBW) Doppler broadened cross section was compared with that of the cross section generated by conventional MLBW (Con MLBW) formalism for {sup 2}38U isotope using MATLAB. The conventional method requires Doppler broadening of all resonances, including resonances far from the target energy point, which do not change much with respect to the temperature change. The energy window concept makes Doppler broadening possible with a smaller number of resonances neighboring to the energy point we are interested in, and just adds up 0 K temperature cross sections of other resonances. Multi-level Breit-Wigner formalism and the Doppler broadening method were used to construct microscopic cross sections of {sup 238}U at different temperatures. The energy window concept was applied only for the 1st resonance energy region (4.5∼11.2 eV). The energy window concept demonstrates high competitiveness because the relative differences were less than 0.0016% for all types of cross sections. The advantage of the energy window concept is that the number of resonances broadened for every energy point is significantly reduced, which allows a reduction of computation time by almost 45 % of Doppler broadening time of the cross section generation at temperatures higher than 0 K.

  8. On the Fly Doppler Broadening Using Multipole Representation

    International Nuclear Information System (INIS)

    Khassenov, Azamat; Choi, Sooyoung; Lee, Deokjung

    2015-01-01

    On the Fly Doppler broadening is the technique to avoid pre-generation of the microscopic cross section, in other words, reduce the amount of storage. Currently, there are different types of formalisms used by NJOY code to generate reaction cross section and accomplish its Doppler broadening. Single-Level Breit-Wigner (SLBW) formalism is limited to well-separated resonances, in other words, it does not consider interference between energy levels. Multi-Level Breit- Wigner formalism (MLBW) was tested as the candidate for the cross section generation in the Monte Carlo code, which is under development in UNIST. According to the results, MLBW method requires huge amount of computational time to produce cross section at certain energy point. Reich-Moore (RM) technique can generate only 0K cross section, which means that it cannot produce broaden cross section directly from resonance parameters. The first step was to convert resonance parameters given in nuclear data file into multipoles. MPR shows very high potential to be used as the formalism in the on-the-fly Doppler broadening module of MCS. One of the main reasons is that comparison of the time cost shown in Table IV supports application of multipole representation

  9. Doppler ultrasound study of penis in men with systemic sclerosis: a correlation with Doppler indices of renal and digital arteries.

    Science.gov (United States)

    Rosato, E; Barbano, B; Gigante, A; Cianci, R; Molinaro, I; Quarta, S; Digiulio, M A; Messineo, D; Pisarri, S; Salsano, F

    2013-01-01

    Erectile dysfunction (ED) prevalence in male systemic sclerosis (SSc) is high and its pathogenesis is unclear. The aim of the study is to assess correlation between Doppler ultrasound indices of penis and kidneys or digital arteries in male systemic sclerosis. Fourteen men with systemic sclerosis were enrolled in this study. Erectile function was investigated by the International Index of Erectile Function-5. Peak systolic velocity, end diastolic velocity, resistive index, pulsative index, and systolic/diastolic ratio were measured on the cavernous arteries at the peno-scrotal junction in the flaccid state, on the interlobar artery of both kidneys and all ten proper palmar digital arteries. Ten (71 percent) patients have an International Index of Erectile Function-5 less than 21. Reduction of penis peak systolic velocity was observed in all SSc subjects. Doppler indices of cavernous arteries correlate with the International Index of Erectile Function-5. The renal and digital arteries resistive index demonstrated a good correlation (p less than 0.0001) with International Index of Erectile Function-5. A positive correlation exists between penis and kidney arteries Doppler indices: end diastolic velocity (p less than 0.05, r=0.54), resistive index (p less than 0.0001, r=0.90), systolic/diastolic ratio (p less than 0.01, r=0.69). A positive correlation was observed between penis and digital arteries Doppler indices: peak systolic velocity (p less than 0.01, r=0.68), end diastolic velocity (p less than 0.01, r=0.75), resistive index (p less than 0.001, r=0.79), systolic/diastolic ratio (p less than 0.05, r=0.59). A correlation exists between arterial impairment of penis and renal or digital arteries.

  10. An ocean current inversion accuracy analysis based on a Doppler spectrum model

    Institute of Scientific and Technical Information of China (English)

    BAO Qingliu; ZHANG Youguang; LIN Mingsen; GONG Peng

    2017-01-01

    Microwave remote sensing is one of the most useful methods for observing the ocean parameters.The Doppler frequency or interferometric phase of the radar echoes can be used for an ocean surface current speed retrieval,which is widely used in spaceborne and airborne radars.While the effect of the ocean currents and waves is interactional.It is impossible to retrieve the ocean surface current speed from Doppler frequency shift directly.In order to study the relationship between the ocean surface current speed and the Doppler frequency shift,a numerical ocean surface Doppler spectrum model is established and validated with a reference.The input parameters of ocean Doppler spectrum include an ocean wave elevation model,a directional distribution function,and wind speed and direction.The suitable ocean wave elevation spectrum and the directional distribution function are selected by comparing the ocean Doppler spectrum in C band with an empirical geophysical model function (CDOP).What is more,the error sensitivities of ocean surface current speed to the wind speed and direction are analyzed.All these simulations are in Ku band.The simulation results show that the ocean surface current speed error is sensitive to the wind speed and direction errors.With VV polarization,the ocean surface current speed error is about 0.15 m/s when the wind speed error is 2 m/s,and the ocean surface current speed error is smaller than 0.3 m/s when the wind direction error is within 20° in the cross wind direction.

  11. Fresh look at the doppler changes in pregnancies with placental-based complications

    Directory of Open Access Journals (Sweden)

    S Dikshit

    2011-01-01

    Full Text Available Placental-based complications of pregnancy can be classified as acute and chronic. An example of acute placental complication is abruptio placenta. The chronic placental complications include pregnancy induced hypertension (PIH and idiopathic Intrauterine growth restriction (IUGR. The fetus is at risk for perinatal complications in both acute and chronic conditions. Here we take a look at the natural history of the Doppler parameters in chronic conditions. The techniques used for assessing the fetal well-being include, clinical methods, biophysical tests, conventional ultrasonography, and fetal Doppler studies. Arterial Doppler studies are used to assess the well-being of the fetus and to determine the timing of delivery. However, arterial Dopplers predict only the subset of fetuses at risk of having perinatal complications. Venous Dopplers have been used to improve upon the prognostication. However, by the time the commonly used venous Doppler signs, that is, ′A′ wave reversal in ductus venosus (DV is present, the fetus is likely to be already compromised. The fetus tries to adapt to the environment of deprivation by making a series of changes in the umbilical artery circulation, cerebral circulation, and hepatic circulation. As a result of these adaptations, the fetus overcomes the state of chronic hypoxia. This article takes a look at these changes and also the effect of these adaptations. It is suggested that serial comparisons of the venous flow characteristics of the DV and inferior vena cava (IVC can provide an early indication of the impending decompensation and can be used to predict the time the delivery.

  12. Doppler color flow mapping of peripheral vessels: Comparison of angiodynography with conventional duplex US

    International Nuclear Information System (INIS)

    Merritt, C.R.B.; Bluth, E.I.; Sullivan, M.A.

    1986-01-01

    A new Doppler color flow imager was compared to duplex US in the evaluation of carotid and peripheral vessels in 50 patients. A 7.5-MHz transducer permitted simultaneous high-resolution real-time imaging of Doppler flow and tissue. The system was found to have excellent image quality and Doppler sensitivity. Flow characteristics and velocity measurements obtained with this system correlated well with those obtained using the duplex scanner and were obtained more quickly than with the conventional system, allowing more complete assessment of flow characteristics. Color Doppler flow imaging appears to be an extremely promising method for the rapid and effective evaluation of peripheral vascular flow

  13. Contrast-enhanced power Doppler US of hepatocellular carcinomas: Quantitative analysis

    International Nuclear Information System (INIS)

    Kim, Ah Young; Choi, Byung Ihn; Kim, Tae Kyoung; Lee, Kyoung Ho; Han, Joon Koo

    1999-01-01

    To determine peak time and duration of contrast enhancement of nodular hepatocellular carcinoma (HCC) on contrast-enhancement power Doppler ultrasound (US) with Levovist by quantitative analysis. Twenty eight patients with nodular HCC were prospectively evaluated with power Doppler US by one examiner. Serial images were obtained before and after injection of 300 mg/mL US contrast agent (SH U 508 A, Levovist, Schering) with the injection rate of 0.2 mL/sec. Power Doppler signals on obtained digital images were quantified using 'Ultrasound Imaging Tool Version 1.0' (Seoul, Korea). The grade, peak time and duration of contrast enhancement of the tumors were analyzed. For nodular HCCs, mean peak enhancement time was 60 seconds after injection of Levovist (mean enhanced area 41.6 ± 28.6 %). These tumoral enhancement decreased from 90 seconds and returned to near baseline state at 5 minutes after injection of Levovist. Maximum enhanced areas (%) were variable at a range of 8-98.5% and mean maximum enhanced area was 46.4 ± 28.6%. On contrast-enhanced power Doppler US with Levovist, nodular HCCs showed peak contrast enhancement (41.6± 28.6) at 60 seconds after injection of contrast agent. This tumoral enhancement nearly disappeared at 5 minutes after injection of contrast agent.

  14. Method and system of doppler correction for mobile communications systems

    Science.gov (United States)

    Georghiades, Costas N. (Inventor); Spasojevic, Predrag (Inventor)

    1999-01-01

    Doppler correction system and method comprising receiving a Doppler effected signal comprising a preamble signal (32). A delayed preamble signal (48) may be generated based on the preamble signal (32). The preamble signal (32) may be multiplied by the delayed preamble signal (48) to generate an in-phase preamble signal (60). The in-phase preamble signal (60) may be filtered to generate a substantially constant in-phase preamble signal (62). A plurality of samples of the substantially constant in-phase preamble signal (62) may be accumulated. A phase-shifted signal (76) may also be generated based on the preamble signal (32). The phase-shifted signal (76) may be multiplied by the delayed preamble signal (48) to generate an out-of-phase preamble signal (80). The out-of-phase preamble signal (80) may be filtered to generate a substantially constant out-of-phase preamble signal (82). A plurality of samples of the substantially constant out-of-phase signal (82) may be accumulated. A sum of the in-phase preamble samples and a sum of the out-of-phase preamble samples may be normalized relative to each other to generate an in-phase Doppler estimator (92) and an out-of-phase Doppler estimator (94).

  15. Three-dimensional Doppler ultrasound findings in healthy wrist and finger tendon sheaths

    DEFF Research Database (Denmark)

    Ammitzboll-Danielsen, Mads; Janta, Iustina; Torp-Pedersen, Søren

    2016-01-01

    interpretation of Doppler signals when diagnosing tenosynovitis. Method Forty healthy participants (20 women and 20 men age 23-67 years) without prior history of arthritis, tendon diseases or present pain in their hands were included. Twenty participants had 3D Doppler US of the second and third finger...... participant. No significant difference in feeding vessels was seen between the radial and carpal level in the wrist (p = 0.06) or between the second and third flexor tendon sheath (p = 0.84). Conclusion Doppler findings in or in close proximity to the tendon sheaths were common in wrists and fingers...

  16. Laser sub-Doppler cooling of atoms in an arbitrarily directed magnetic field

    International Nuclear Information System (INIS)

    Chang, Soo; Kwon, Taeg Yong; Lee, Ho Seong; Minogin, V.G.

    2002-01-01

    We analyze the influence of an arbitrarily directed uniform magnetic field on the laser sub-Doppler cooling of atoms. The analysis is done for a (3+5)-level atom excited by a σ + -σ - laser field configuration. Our analysis shows that the effects of the magnetic field depend strongly on the direction of the magnetic field. In an arbitrarily directed magnetic field the laser cooling configuration produces both the main resonance existing already at zero magnetic field and additional sub-Doppler resonances caused by two-photon and higher-order multiphoton processes. These sub-Doppler resonances are, however, well separated on the velocity scale if the Zeeman shift exceeds the widths of the resonances. This allows one to use the main sub-Doppler resonance for an effective laser cooling of atoms even in the presence of the magnetic field. The effective temperature of the atomic ensemble at the velocity of the main resonance is found to be almost the same as in the absence of the magnetic field. The defined structure of the multiphoton resonances may be of importance for the sub-Doppler laser cooling of atoms, atomic extraction from magneto-optical traps, and applications related to the control of atomic motion

  17. Teratoma congênito de orofaringe: relato de caso Oropharyngeal congenital teratoma: a case report

    Directory of Open Access Journals (Sweden)

    Yuri Seguchi Chaves

    2005-02-01

    Full Text Available O teratoma congênito de orofaringe é o tipo mais raro de teratoma, compreendendo apenas 2% desses tumores fetais. O diagnóstico deve ser realizado o mais precocemente possível, preferencialmente durante o pré-natal. O prognóstico irá depender do tamanho e localização da lesão, da velocidade de crescimento desta, do envolvimento de estruturas intracranianas e da ressecção adequada do tumor com equipe multidisciplinar. Relatamos o caso de uma paciente que teve diagnosticado durante a gestação feto com teratoma congênito de orofaringe (epignathus por meio de ultra-sonografia. O feto evoluiu para óbito intra-uterino na 29ª semana de gestação, sendo então induzido o parto por via vaginal. O exame anatomopatológico revelou feto do sexo feminino, compatível com 27-28 semanas, teratoma orofaríngeo e outras malformações congênitas.Oropharyngeal teratoma is the most rare type of teratoma, with only 2% of fetal teratomas. The diagnosis must be established as early as possible, preferably during the prenatal period. The prognosis will depend on the size and location of the lesion, growth rate of the lesion, degree of intracranial spread, its resectability, and immediate care at birth by a multisciplinary team. We report aparticular case of congenital oropharyngeal teratoma (epignathus. The diagnosis was made during the prenatal period by ultrasound, and the fetus evolved to intrauterine death at the 29th week. The anatomopathological examination revealed a female fetus, compatible with 27-28 weeks, oropharyngeal teratoma and congenital malformations.

  18. Optimized variational analysis scheme of single Doppler radar wind data

    Science.gov (United States)

    Sasaki, Yoshi K.; Allen, Steve; Mizuno, Koki; Whitehead, Victor; Wilk, Kenneth E.

    1989-01-01

    A computer scheme for extracting singularities has been developed and applied to single Doppler radar wind data. The scheme is planned for use in real-time wind and singularity analysis and forecasting. The method, known as Doppler Operational Variational Extraction of Singularities is outlined, focusing on the principle of local symmetry. Results are presented from the application of the scheme to a storm-generated gust front in Oklahoma on May 28, 1987.

  19. Method and apparatus for Doppler frequency modulation of radiation

    Science.gov (United States)

    Margolis, J. S.; Mccleese, D. J.; Shumate, M. S.; Seaman, C. H. (Inventor)

    1980-01-01

    A method and apparatus are described for frequency modulating radiation, such as from a laser, for optoacoustic detectors, interferometers, heterodyne spectrometers, and similar devices. Two oppositely reciprocating cats-eye retroreflectors are used to Doppler modulate the radiation. By reciprocally moving both retroreflectors, the center of mass is maintained constant to permit smooth operation at many Hertz. By slightly offsetting the axis of one retroreflector relative to the other, multiple passes of a light beam may be achieved for greater Doppler shifts with the same reciprocating motion of the retroreflectors.

  20. Analysis of multiple scattering effects in optical Doppler tomography

    DEFF Research Database (Denmark)

    Yura, H.T.; Thrane, L.; Andersen, Peter E.

    2005-01-01

    Optical Doppler tomography (ODT) combines Doppler velocimetry and optical coherence tomography (OCT) to obtain high-resolution cross-sectional imaging of particle flow velocity in scattering media such as the human retina and skin. Here, we present the results of a theoretical analysis of ODT where...... multiple scattering effects are included. The purpose of this analysis is to determine how multiple scattering affects the estimation of the depth-resolved localized flow velocity. Depth-resolved velocity estimates are obtained directly from the corresponding mean or standard deviation of the observed...

  1. Calculation results and experimental testing of doppler feedback coefficients

    International Nuclear Information System (INIS)

    Yang Shunhai

    1989-01-01

    The Doppler feedback coefficients are calculated by the interpolation and group collapsing method from multigroup self-shielding factors and infinite dilution cross sections rather than effective resonance integrals by using resonance data base. Since many updated sets of multigroup data are in existence to be selected, the calculation process can be simplified. The heterogeneous effects are taken into account by equivalence relation. The computer code of Doppler feedback coefficients is created on computer CYBER-825 and PDP-11. The results calculated are in good agreement with the experiments

  2. The use of contrast-enhanced color doppler ultrasound in the differentiation of retinal detachment from vitreous membrane

    International Nuclear Information System (INIS)

    Han, Sang Suk; Chang, Seung Kook; Yoon, Jung Hee; Lee, Young Joon

    2001-01-01

    To compare the clinical utility of contrast-enhanced color Doppler US in the differentiation of retinal detachment (RD) from vitreous membrane (VM) with that of various conventional US modalities, and to analyze the enhancement patterns in cases showing an enhancement effect. In 32 eyes examined over a recent two-year period, RD (n=14) and VM (n=18) were confirmed by surgery (n=28) or clinical follow-up (n=4). In all cases, gray-scale, color Doppler, and power Doppler US were performed prior to contrast injection, and after the intravenous injection of Levovist (Schering, Berlin) by hand for 30 seconds at a dose of 2.5 g and a concentration of 300 mg/mL via an antecubital vein, contrast-enhanced color Doppler US was performed. At Doppler US, the diagnostic criterion for RD and VM was whether or not color signals were visualized in membranous structures. Diagnostic accuracy was 78% at gray-scale US, 81% at color Doppler US, 59% at power Doppler US, and 97% at contrast-enhanced color Doppler US. The sensitivity of color Doppler US to color signals in RD increased from 57% to 93% after contrast enhancement. The enhancement patterns observed were signal accentuation (n=3), signal extension (n=2), signal addition (n=3), and new signal visualization (n=5). Contrast-enhanced color Doppler US was the most accurate US modality for differentiating RD from VM, showing a significantly increased signal detection rate in RD

  3. Laser Doppler thermometry in flat flames

    NARCIS (Netherlands)

    Maaren, van A.; Goey, de L.P.H.

    1994-01-01

    Laser Doppler Velocimetry measurements are performed in flat flames, stabilized on a newly developed flat-flame burner. It is shown that the velocity component perpendicular to the main flow direction, induced by expansion in the reaction zone and buoyancy in the burnt gas, is significant. A method

  4. Varicocele e volume testicular em adolescentes e adultos jovens portadores de esquistossomose hepatoesplênica cirúrgica

    Directory of Open Access Journals (Sweden)

    Brandt Frederico Teixeira

    2003-01-01

    Full Text Available OBJETIVO: Avaliar o volume testicular e a prevalência de varicocele em adolescentes e adultos jovens portadores de esquistossomose na forma hepatoesplênica associada a varizes sangrentas de esôfago. MÉTODOS: O estudo envolveu 22 adolescentes masculinos com esquistossomose na forma descrita, submetidos à esplenectomia, ligadura da veia gástrica esquerda e auto-implante de tecido esplênico no grande omento quando crianças. O tempo médio de seguimento foi de 4 anos após a intervenção. O grupo de voluntários sadios foi de adolescentes de uma escola na mesma região onde os casos operados viviam. Eles foram selecionados de forma randomizada, considerando a faixa de idade, características epidemiológicas e não serem infestados por equistossomose. Todos os participantes possuíam história clínica completa e foram submetidos a exame físico e ultra-sonográfico. Foi dado atenção especial as características sexuais, ultra-sonografia testicular e dopplerfluxometria das veias espermáticas. RESULTADOS: Dos pacientes classificados como adultos pela idade cronológica, 53,8% tinham genitais com características infantis. A incidência de varicocele foi igual a 61,5% no grupo afetado e 40% no grupo controle, sem diferença estatística entre os grupos (x 2 =1,77; g.1.=1; p=0,18 3 p Fisher=0,16, acometendo predominantemente o testículo esquerdo, em ambos os grupos. CONCLUSÃO: Pacientes com doença esquistossomótica cirúrgica tinham significante déficit no desenvolvimento puberal e genital, no volume testicular, especialmente do lado esquerdo, e alta prevalência de varicocele (61.5% sem uma associação direta com atrofia testicular.

  5. Análise da fórmula SRK/T no cálculo de lente intra-ocular em cães portadores de catarata Analysis of the SRK/T formula for calculation of intra-ocular lens in dogs carrying cataract

    Directory of Open Access Journals (Sweden)

    T.P. Peixoto

    2008-12-01

    Full Text Available Foram utilizados 20 cães de raças e idades variadas, machos e fêmeas, portadores de catarata e não diabéticos, os quais foram submetidos ao exame oftálmico. Posteriormente, realizaram-se mensurações oculares empregando-se um ecobiômetro ultra-sônico (ultra-sonografia modo-A para o cálculo do poder dióptrico da lente intra-ocular por meio da fórmula SRK/T. O comprimento axial médio foi de 19,94±1,12mm. Todos os animais foram submetidos à facoemulsificação extracapsular. A lente calculada foi implantada no transoperatório da cirurgia de catarata, obtendo-se média de 37,33±3,05D. A avaliação pós-cirúrgica do erro refracional aos 60 dias de pós-operatório, pela retinoscopia, com a utilização da esquiascopia, foi de 5,57±1,59D. A fórmula SRK/T não ofereceu bons resultados.Twenty males and females non-diabetic dogs of different breeds and ages underwent ophthalmic examination because they presented catarats. Ocular measurements were performed by echobiometry (A-scan ultrasound for intraocular lens power calculation using the SRK/T formula. The obtained mean axial length was 19.94±1.12mm. All animals were submitted to extracapsular phacoemulsification; the mean intraocular lens power implanted was 37.33±3.05. At 60 days postoperative, the refractional error assessed via retinoscopy was 5.57±1.59 D. The SRK/T formula did not offer good results.

  6. Renal duplex Doppler ultrasound findings in diabetics

    International Nuclear Information System (INIS)

    Shim, Hyang Yee; Kim, Young Geun; Kook, Cheol Keu; Yoon, Chong Hyun; Lee, Shin Hyung; Lee, Chang Joon

    1993-01-01

    The correlation between clinical-laboratory findings and renal duplex Doppler ultrasound findings was studied in 45 patients with diabetes mellitus to see the role of duplex Doppler ultrasound in the detection of diabetic nephropathy. The resistive indices in patients with elevated serum creatinine, BUN, proteinuria, and systolic blood pressure levels were statistically significantly higher than those in patients with normal levels (p<0.05). Also resistive indics in patients with retinopathy were higher than that in patients without retinopathy (p<0.05). But the ultrasound morphologic changes of kidney such as renal length, cortical eye-catching, and corticomedullarycontrast were not well correlated with clinical-laboratory data and resistive index. The resistive index of the kidney in conjunction with clinical-laboratory data in diabetics may be helpful in the evaluation of diabetic nephropathy

  7. Renal duplex Doppler ultrasound findings in diabetics

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Hyang Yee; Kim, Young Geun; Kook, Cheol Keu; Yoon, Chong Hyun; Lee, Shin Hyung; Lee, Chang Joon [National Medical Center, Seoul (Korea, Republic of)

    1993-12-15

    The correlation between clinical-laboratory findings and renal duplex Doppler ultrasound findings was studied in 45 patients with diabetes mellitus to see the role of duplex Doppler ultrasound in the detection of diabetic nephropathy. The resistive indices in patients with elevated serum creatinine, BUN, proteinuria, and systolic blood pressure levels were statistically significantly higher than those in patients with normal levels (p<0.05). Also resistive indics in patients with retinopathy were higher than that in patients without retinopathy (p<0.05). But the ultrasound morphologic changes of kidney such as renal length, cortical eye-catching, and corticomedullarycontrast were not well correlated with clinical-laboratory data and resistive index. The resistive index of the kidney in conjunction with clinical-laboratory data in diabetics may be helpful in the evaluation of diabetic nephropathy

  8. The color Doppler ultrasonography in in the diagnosis of deep vein thrombosis

    International Nuclear Information System (INIS)

    Ameneiro Perez, Santiago; Alvarez Sanchez, Jose A.; Rodriguez Villalonga, Luis; Borras Migues, Marisela; Quinnones Castro, Mayda

    2004-01-01

    The paper was aimed at evaluating the accuracy of color Doppler ultrasonography, a noninvasive method, in the diagnosis of deep vein thrombosis of the lower limbs, comparing it to the results of the cruel and costly diagnostic g olden rule , that is, phlebography. Methods: Color Doppler ultrasonography served to assess 102 patients clinically suspected of deep vein thrombosis of the lower limbs, taking into account the following criteria: vein compressibility, echographic images, color, Vein Doppler signal modulation after several maneuvers and distal compression. Sensitivity, specificity, positive and negative predictive values and diagnostic efficacy were estimated for each criteria, taking the phlebography as a reference. Results: Total or partial lack of vein compressibility combined with the vein flow evaluation is the ultrasonographic criterion that reveals higher degree of sensitivity, specificity and efficacy (0,98; 0,95 and 0,97 respectively. Color Doppler ultrasonography is a highly effective noninvasive diagnostic method that detects deep vein thrombosis in proximal areas of the lower limbs

  9. Accuracy of doppler ultrasound in diagnosis of endometrial carcinoma

    International Nuclear Information System (INIS)

    Batool, S.; Raza, S.; Manzur, S.

    2013-01-01

    Objective: To determine the accuracy of Doppler ultrasound in the diagnosis of endometrial carcinoma in patients presenting with post-menopausal bleeding while taking histopathological findings as the gold standard. Methods: The cross-sectional study was done at the Department of Radiology, Bahawal Victoria Hospital, Bahawalpur, from April 1 to September 30, 2009, and comprised 128 patients above 50 years of age having history of post-menopausal bleeding and who were referred to the department. Name, age and hospital registration number were recorded on a proforma. Doppler ultrasound was performed and endometrial thickness and uterine artery resistive index were recorded on transabdominal ultrasonography. Patients with endometrial thickness of more than 5mm and uterine artery resistive index of less than 0.7 were considered to be having endometrial carcinoma. Histopathology findings were also recorded using the hospital registration number of the patient. The findings of Doppler ultrasound scan were validated with the findings of histopathology. Results: Of the 128 patients, 48 (37.5%) were between the ages of 51 and 55 years; 46 (35.93%) were in the 56-60 age group; and 34 (26.57%) were over 65 years. On the basis of Doppler ultrasound findings, 106 (82.8%) patients were diagnosed as having endometrial carcinoma, while 22 (17.19%) were declared negative. Ultrasonography results were compared with histopathology findings. The percentages of true positive, true negative, false positive and false negative were calculated. There were 103 (80.47%) true positive; 12 (9.37%) false positive; 10 (7.81%) true negative; and 3 (2.35%) false negative. Specificity, sensitivity, positive predictive value and negative predictive value were found to be 97.16%, 76%, 89.56% and 76.92% respectively. Conclusion: The use of Doppler ultrasonography in non-invasive diagnosis of endometrial carcinoma in patients presenting with post-menopausal bleeding was quite useful with good

  10. Operator auditory perception and spectral quantification of umbilical artery Doppler ultrasound signals.

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    Ann Thuring

    Full Text Available OBJECTIVE: An experienced sonographer can by listening to the Doppler audio signals perceive various timbres that distinguish different types of umbilical artery flow despite an unchanged pulsatility index (PI. Our aim was to develop an objective measure of the Doppler audio signals recorded from fetoplacental circulation in a sheep model. METHODS: Various degrees of pathological flow velocity waveforms in the umbilical artery, similar to those in human complicated pregnancies, were induced by microsphere embolization of the placental bed (embolization model, 7 lamb fetuses, 370 Doppler recordings or by fetal hemodilution (anemia model, 4 lamb fetuses, 184 recordings. A subjective 11-step operator auditory scale (OAS was related to conventional Doppler parameters, PI and time average mean velocity (TAM, and to sound frequency analysis of Doppler signals (sound frequency with the maximum energy content [MAXpeak] and frequency band at maximum level minus 15 dB [MAXpeak-15 dB] over several heart cycles. RESULTS: WE FOUND A NEGATIVE CORRELATION BETWEEN THE OAS AND PI: median Rho -0.73 (range -0.35- -0.94 and -0.68 (range -0.57- -0.78 in the two lamb models, respectively. There was a positive correlation between OAS and TAM in both models: median Rho 0.80 (range 0.58-0.95 and 0.90 (range 0.78-0.95, respectively. A strong correlation was found between TAM and the results of sound spectrum analysis; in the embolization model the median r was 0.91 (range 0.88-0.97 for MAXpeak and 0.91 (range 0.82-0.98 for MAXpeak-15 dB. In the anemia model, the corresponding values were 0.92 (range 0.78-0.96 and 0.96 (range 0.89-0.98, respectively. CONCLUSION: Audio-spectrum analysis reflects the subjective perception of Doppler sound signals in the umbilical artery and has a strong correlation to TAM-velocity. This information might be of importance for clinical management of complicated pregnancies as an addition to conventional Doppler parameters.

  11. Normal Doppler velocimetry of renal vasculature in Persian cats.

    Science.gov (United States)

    Carvalho, Cibele F; Chammas, Maria C

    2011-06-01

    Renal diseases are common in older cats. Decreased renal blood flow may be the first sign of dysfunction and can be evaluated by Doppler ultrasound. But previous studies suggest that the resistive index (RI) has a low sensitivity for detecting renal disease. Doppler waveforms of renal and intrarenal arteries demonstrate decreased blood flow before there are any changes in the RI. The purpose of this study was to evaluate the normal Doppler flowmetrics parameters of renal arteries (RAs), interlobar arteries (IAs) and abdominal aorta (AO) in adult healthy, Persian cats. Twenty-five Persian cats (13 females and 12 males with mean age of 30 months and an age range 12-60 months) with normal clinical examinations and biochemical tests and normal systemic blood pressure were given B-mode ultrasonographies in order to exclude all nephropathies, including polycystic kidney disease. All measurements were performed on both kidneys. Both kidneys (n=50) were examined by color mapping of the renal vasculature. Pulsed Doppler was used to examine both RAs, the IAs at cranial, middle and caudal sites, and the AO. The RI was calculated for all of the vessels. Early systolic acceleration (ESA) of RA and IA was obtained with Doppler spectral analysis. Furthermore, the ratio indices between RA/AO, and IA/RA velocities were calculated. The mean values of peak systolic velocity (PSV) and the diameter for AO were 53.17±13.46 cm/s and 0.38±0.08 cm, respectively. The mean RA diameter for all 50 kidneys was 0.15±0.02 cm. Considering the velocimetric values in both RAs, the mean PSV and RI that were obtained were 41.17±9.40 cm/s and 0.54±0.07. The RA had a mean ESA of 1.12±1.14 m/s(2) and the calculated upper limit of the reference value was 3.40 m/s(2). The mean renal-aortic ratio was 0.828±0.296. The IA showed PSV and RI values of 32.16±9.33 cm/s and 0.52±0.06, respectively. The mean ESA of all IAs was 0.73±0.61 m/s(2). The calculated upper limit of the reference value was 2.0m

  12. Low-frequency high-definition power Doppler in visualizing and defining fetal pulmonary venous connections.

    Science.gov (United States)

    Liu, Lin; He, Yihua; Li, Zhian; Gu, Xiaoyan; Zhang, Ye; Zhang, Lianzhong

    2014-07-01

    The use of low-frequency high-definition power Doppler in assessing and defining pulmonary venous connections was investigated. Study A included 260 fetuses at gestational ages ranging from 18 to 36 weeks. Pulmonary veins were assessed by performing two-dimensional B-mode imaging, color Doppler flow imaging (CDFI), and low-frequency high-definition power Doppler. A score of 1 was assigned if one pulmonary vein was visualized, 2 if two pulmonary veins were visualized, 3 if three pulmonary veins were visualized, and 4 if four pulmonary veins were visualized. The detection rate between Exam-1 and Exam-2 (intra-observer variability) and between Exam-1 and Exam-3 (inter-observer variability) was compared. In study B, five cases with abnormal pulmonary venous connection were diagnosed and compared to their anatomical examination. In study A, there was a significant difference between CDFI and low-frequency high-definition power Doppler for the four pulmonary veins observed (P low-frequency high-definition power Doppler was higher than that when employing two-dimensional B-mode imaging or CDFI. There was no significant difference between the intra- and inter-observer variabilities using low-frequency high-definition power Doppler display of pulmonary veins (P > 0.05). The coefficient correlation between Exam-1 and Exam-2 was 0.844, and the coefficient correlation between Exam-1 and Exam-3 was 0.821. In study B, one case of total anomalous pulmonary venous return and four cases of partial anomalous pulmonary venous return were diagnosed by low-frequency high-definition power Doppler and confirmed by autopsy. The assessment of pulmonary venous connections by low-frequency high-definition power Doppler is advantageous. Pulmonary venous anatomy can and should be monitored during fetal heart examination.

  13. Doença hepática gordurosa não alcoólica em escolares obesos Nonalcoholic fatty liver disease in obese children

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    Fabíola Isabel S. Souza

    2008-06-01

    Full Text Available OBJETIVO: Avaliar a prevalência de alterações hepáticas ao ultra-som e de elevação da alanina aminotransferase (ALT em crianças com sobrepeso e obesidade, além de relacionar a presença de alterações com peroxidação lipídica, perfil lipídico e resistência insulínica. MÉTODOS: Estudo transversal, prospectivo e controlado de 67 crianças com sobrepeso/obesidade (38 do sexo feminino e média de idade de 8,6 anos, pareadas por sexo e idade com 65 eutróficas. A avaliação bioquímica consistiu de perfil lipídico (LDL-c, HDL-c e triglicerídeos; ALT; substâncias reativas ao ácido tiobarbitúrico (TBARS; glicemia e insulina, utilizadas para o cálculo do Homeostasis Model Assessment Insulin Resistance (HOMA-IR. A esteatose hepática, avaliada por ultra-sonografia por um único examinador, foi classificada em difusa leve, moderada e grave. RESULTADOS: Elevação de ALT (>40U/L foi encontrada em 3% e alterações ultra-sonográficas do fígado em 57,4% das crianças com sobrepeso e obesidade. O Grupo Sobrepeso/Obesidade apresentou maior percentual de ALT >18U/L (OR 4,2; p=0,0006 e de hipertrigliceridemia (OR 4,2; p18U/L. CONCLUSÕES: A freqüência de ALT >40U/L foi baixa e a de esteatose foi alta. As alterações ultra-sonográficas hepáticas não mostraram associação com o estado nutricional nem com os níveis de ALT. Por sua vez, triglicerídeos aumentados associaram-se com níveis mais elevados de ALT.OBJECTIVE: To evaluate the prevalence of altered hepatic ultrasound and elevated serum alanine aminotransferase (ALT in overweight and obese children, as well as to relate them to lipid peroxidation, lipid profile and insulin resistance. METHODS: A prospective, controlled, cross-sectional study was performed with 67 overweight and obese children (38 female, mean age of 8,6 years paired by gender and age with 65 eutrophic controls. The following parameters were evaluated: lipid profile (LDL-c, HDL-c, triglycerides, ALT, lipid

  14. Glare Spot Phase Doppler Anemometry

    Science.gov (United States)

    Hespel, Camille; Ren, Kuanfang; Gréhan, Gérard; Onofri, Fabrice

    2007-06-01

    The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index would be also interesting since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemometry which uses two large beams. In this case, the images of the particle formed by the reflected and refracted light, known as glare spots, are separated in space. When a particle passes in the probe volume, the two parts in a signal obtained by a detector in forward direction are then separated in time. If two detectors are used the phase differences between two signals, the distance and the intensity ratio of reflected and refracted parts can be obtained and they provide rich information about the particle diameter and its refractive index, as well as its velocity. This paper is devoted to the numerical study of such a configuration with two theoretical models: geometrical optics and rigorous electromagnetism solution.

  15. Aspectos ultra-sonográficos da trombose da veia porta Ultrasonographic features of portal vein thrombosis

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    Márcio Martins Machado

    2006-04-01

    Full Text Available A trombose da veia porta pode estar associada a várias alterações, como a presença de tumores (por exemplo: hepatocarcinoma, doença metastática hepática e carcinoma do pâncreas, pancreatite, hepatite, septicemia, trauma, esplenectomia, derivações porto-cava, estados de hipercoagulabilidade (por exemplo: gravidez, em neonatos (por exemplo: onfalite e cateterização da veia umbilical e desidratação aguda. Os autores discutem, neste artigo, os aspectos ultra-sonográficos da trombose de veia porta e alguns aspectos de relevância clínica.Portal vein thrombosis may be associated with many alterations, such as the presence of tumors (for example, hepatocellular carcinoma, metastatic liver disease and carcinoma of the pancreas as well as pancreatitis, hepatitis, septicemia, trauma, splenectomy, portacaval shunts, hypercoagulable conditions (for example, pregnancy, in neonates (for example, omphalitis and umbilical vein catheterization and in acute dehydration. The authors discuss herein the sonographic features of portal vein thrombosis as well as some aspects of clinical relevance.

  16. Two-dimensional intraventricular flow mapping by digital processing conventional color-Doppler echocardiography images.

    Science.gov (United States)

    Garcia, Damien; Del Alamo, Juan C; Tanne, David; Yotti, Raquel; Cortina, Cristina; Bertrand, Eric; Antoranz, José Carlos; Perez-David, Esther; Rieu, Régis; Fernandez-Aviles, Francisco; Bermejo, Javier

    2010-10-01

    Doppler echocardiography remains the most extended clinical modality for the evaluation of left ventricular (LV) function. Current Doppler ultrasound methods, however, are limited to the representation of a single flow velocity component. We thus developed a novel technique to construct 2D time-resolved (2D+t) LV velocity fields from conventional transthoracic clinical acquisitions. Combining color-Doppler velocities with LV wall positions, the cross-beam blood velocities were calculated using the continuity equation under a planar flow assumption. To validate the algorithm, 2D Doppler flow mapping and laser particle image velocimetry (PIV) measurements were carried out in an atrio-ventricular duplicator. Phase-contrast magnetic resonance (MR) acquisitions were used to measure in vivo the error due to the 2D flow assumption and to potential scan-plane misalignment. Finally, the applicability of the Doppler technique was tested in the clinical setting. In vitro experiments demonstrated that the new method yields an accurate quantitative description of the main vortex that forms during the cardiac cycle (mean error for vortex radius, position and circulation). MR image analysis evidenced that the error due to the planar flow assumption is close to 15% and does not preclude the characterization of major vortex properties neither in the normal nor in the dilated LV. These results are yet to be confirmed by a head-to-head clinical validation study. Clinical Doppler studies showed that the method is readily applicable and that a single large anterograde vortex develops in the healthy ventricle while supplementary retrograde swirling structures may appear in the diseased heart. The proposed echocardiographic method based on the continuity equation is fast, clinically-compliant and does not require complex training. This technique will potentially enable investigators to study of additional quantitative aspects of intraventricular flow dynamics in the clinical setting by

  17. Brazilian Guidelines for transcranial doppler in children and adolescents with sickle cell disease

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    Clarisse Lopes de Castro Lobo

    2011-02-01

    Full Text Available BACKGROUND: Sickle cell disease is the most common monogenic hereditary disease in Brazil. Although strokes are one of the main causes of morbidity and mortality in these patients, the use of transcranial Doppler to identify children at risk is not universally used. OBJECTIVE: To develop Brazilian guidelines for the use of transcranial Doppler in sickle cell disease children and adolescents, so that related health policies can be expanded, and thus contribute to reduce morbidity and mortality. METHODS: The guidelines were formulated in a consensus meeting of experts in transcranial Doppler and sickle cell disease. The issues discussed were previously formulated and scientific articles in databases (MEDLINE, SciELO and Cochrane were carefully analyzed. The consensus for each question was obtained by a vote of experts on the specific theme. RESULTS: Recommendations were made, including indications for the use of transcranial Doppler according to the sickle cell disease genotype and patients age; the necessary conditions to perform the exam and its periodicity depending on exam results; the criteria for the indication of blood transfusions and iron chelation therapy; the indication of hydroxyurea; and the therapeutic approach in cases of conditional transcranial Doppler. CONCLUSION: The Brazilian guidelines on the use of transcranial doppler in sickle cell disease patients may reduce the risk of strokes, and thus reduce the morbidity and mortality and improve the quality of life of sickle cell disease patients.

  18. Evaluation of factors influencing arterial Doppler waveforms in an in vitro flow phantom

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chang Kyu [Dept. of Radiology, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Kyoung Ho [Dept. of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam (Korea, Republic of); Kim, Seung Hyup [Dept. of Radiology and the Institute of Radiation Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2017-01-15

    The aim of this study was to investigate factors that influence arterial Doppler waveforms in an in vitro phantom to provide a more accurate and comprehensive explanation of the Doppler signal. A flow model was created using a pulsatile artificial heart, rubber or polyethylene tubes, a water tank, and a glass tube. Spectral Doppler tracings were obtained in multiple combinations of compliance, resistance, and pulse rate. Peak systolic velocity, minimum diastolic velocity, resistive index (RI), pulsatility index, early systolic acceleration time, and acceleration index were measured. On the basis of these measurements, the influences of the variables on the Doppler waveforms were analyzed. With increasing distal resistance, the RI increased in a relatively linear relationship. With increasing proximal resistance, the RI decreased. The pulsus tardus and parvus phenomenon was observed with a small acceleration index in the model with a higher grade of stenosis. An increase in the distal resistance masked the pulsus tardus and parvus phenomenon by increasing the acceleration index. Although this phenomenon occurred independently of compliance, changes in the compliance of proximal or distal tubes caused significant changes in the Doppler waveform. There was a reverse relationship between the RI and the pulse rate. Resistance and compliance can alter the Doppler waveforms independently. The pulse rate is an extrinsic factor that also influences the RI. The compliance and distal resistance, as well as proximal resistance, influence the pulsus tardus and parvus phenomenon.

  19. Ophthalmic artery color Doppler ultrasonography in mild-to-moderate preeclampsia

    International Nuclear Information System (INIS)

    Ayaz, Tunahan; Akansel, Gur.; Hayirlioglu, Alper; Arslan, Arzu; Suer, Necdet; Kuru, Ihsan

    2003-01-01

    Objective: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. Methods: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. Results: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. Conclusion: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia

  20. 3D atom microscopy in the presence of Doppler shift

    Science.gov (United States)

    Rahmatullah; Chuang, You-Lin; Lee, Ray-Kuang; Qamar, Sajid

    2018-03-01

    The interaction of hot atoms with laser fields produces a Doppler shift, which can severely affect the precise spatial measurement of an atom. We suggest an experimentally realizable scheme to address this issue in the three-dimensional position measurement of a single atom in vapors of rubidium atoms. A three-level Λ-type atom-field configuration is considered where a moving atom interacts with three orthogonal standing-wave laser fields and spatial information of the atom in 3D space is obtained via an upper-level population using a weak probe laser field. The atom moves with velocity v along the probe laser field, and due to the Doppler broadening the precision of the spatial information deteriorates significantly. It is found that via a microwave field, precision in the position measurement of a single hot rubidium atom can be attained, overcoming the limitation posed by the Doppler shift.

  1. Airborne Doppler Wind Lidar Post Data Processing Software DAPS-LV

    Science.gov (United States)

    Beyon, Jeffrey Y. (Inventor); Koch, Grady J. (Inventor); Kavaya, Michael J. (Inventor)

    2015-01-01

    Systems, methods, and devices of the present invention enable post processing of airborne Doppler wind LIDAR data. In an embodiment, airborne Doppler wind LIDAR data software written in LabVIEW may be provided and may run two versions of different airborne wind profiling algorithms. A first algorithm may be the Airborne Wind Profiling Algorithm for Doppler Wind LIDAR ("APOLO") using airborne wind LIDAR data from two orthogonal directions to estimate wind parameters, and a second algorithm may be a five direction based method using pseudo inverse functions to estimate wind parameters. The various embodiments may enable wind profiles to be compared using different algorithms, may enable wind profile data for long haul color displays to be generated, may display long haul color displays, and/or may enable archiving of data at user-selectable altitudes over a long observation period for data distribution and population.

  2. [The use of intraoperative Doppler ultrasound in endoscopic transsphenoidal surgery].

    Science.gov (United States)

    Sharipov, O I; Kutin, M A; Kalinin, P L; Fomichev, D V; Lukshin, V A; Kurnosov, A B

    2016-01-01

    Doppler ultrasound (DUS) has been widely used in neurosurgical practice to diagnose various cerebrovascular diseases. This technique is used in transsphenoidal surgery to identify the localization of intracranial arteries when making an approach or during tumor resection. To identify the cavernous segment of the internal carotid artery (ICA) and/or basilar artery during endoscopic transsphenoidal surgery, we used a combined device on the basis of a click line curette («Karl Storz») and a 16 MHz Doppler probe (Lassamed). The technique was used in 51 patients during both standard transsphenoidal surgery (23 cases) and transsphenoidal tumor resection through an extended approach (28 cases). Doppler ultrasound was used in different situations: to determine a trajectory of the endonasal transsphenoidal approach in the absence of the normal anatomical landmarks (16 cases), to define the limits of safe resection of a tumor located in the laterosellar region (7), and to implement an extended transsphenoidal endoscopic approach (28). Intraoperative Doppler ultrasound enabled identification of the cavernous segment of the internal carotid artery in 45 cases and the basilar artery in 2 cases; a blood vessel was not found in 4 cases. Injury to the cavernous segment of the internal carotid artery was observed only in 1 case. The use of the described combined device in transsphenoidal surgery turned Doppler ultrasound into an important and useful technique for visualization of the ICA within the tumor stroma as well as in the case of the changed skull base anatomy. Its use facilitates manipulations in a deep and narrow wound and enables inspection of the entire surface of the operative field in various planes, thereby surgery becomes safer due to the possibility of maximum investigation of the operative field.

  3. Tissue doppler echocardiography for evaluating left ventricular functions in obese

    Directory of Open Access Journals (Sweden)

    Mecnun Çetin

    2013-03-01

    Full Text Available Objective: The aim of this study was to investigate theimpact of childhood obesity on ventricular functions usingtissue Doppler echocardiography.Materials and methods: The mitral tissue Doppler signalswere recorded in the apical four-chamber view, with thesample volume placed at the lateral walls of mitral annulus.The mitral flow was examined with the sample Pulse Dopplerpositioned parallely to flow just at the orifice of the mitralleaflets. Twenty obese (mean age, 161.5±25.8 monthsand 20 healthy children (mean age, 151.2±33.5 monthswere included to this study.Results: Body mass index (BMI was significantly higherin obese group (30.92±6.87. Isovolumic relaxation time(IVRT which is one of the left ventricular (LV diastolicfunction parameters was 66.10±7.30 ms in obese group,and 58.70±9.06 ms in the control group. IVRT was significantlyhigher in the obese group (p=0.007. In obesegroup, the mitral annulus tissue Doppler E velocity wasdecreased, flow velocity was increased and decrement inEm/Am ratio was significant. We found significant negativecorrelation between BMI and LV Em/Am ratio. Myocardialperformance index (MPI in obese group and control groupwas 0.50±0.07 and 0.41±0.04, respectively (p<0.001.Between MPI and LV Em/Am ratio there was a significantnegative correlation while MPI showed positive correlationwith BMI. In obese group septal and LV posterior wall thicknesswas shown to be significantly increased compared tothe control group (p<0.001.Conclusion: Our findings, may be important for determinationof the relationship between obesity and cardiovascularrisk factors in children. Tissue Doppler echocardiographicimaging may be useful in revealing this relationship.Key words: obesity, doppler echocardiography, ventricular dysfunction

  4. The Role of Color Doppler Ultrasonography in Characterization of Thyroid Tumors

    International Nuclear Information System (INIS)

    Kim, Hee Soo; Jeon, Pyong; Won, Jong Yoon; Na, Jae Beom; Lee, Hyang Mee; Yoo, Hyung Sik; Lee, Jong Tae; Park, Jeong Soo; Cho, Nam Hoon

    1995-01-01

    To assess the usefulness of color Doppler ultrasonography in the characterization of thyroid tumors, surgically proven 88 nodules in 85 patients were evaluated. Using 10 MHz linear array transducer, gray scale images were initially evaluated. Then, distribution pattern of color signals (marginal, intra-tumoral, mixed) and graded internal vascularity according to morphology of color signal (0:absence of internal signal, 1: spotty, 2: linear,3: branching) were observed on color doppler imaging. Pulsed doppler waves were analyzed with parameters including peak systolic velocity(PSV), resistive index(RI), and pulsatile index(PI). Significantly larger numbers of intra-tumoral type, 20 cases(62.5%), were observed in malignant nodules, whereas mixed forms were predominant in benign group, 37 cases (66%) In graded internal vascularity, malignant nodules tended to have grade 2 or 3 signals, whereas benign nodules tended to have grade 0 or 1 signals. Spectral wave analysis show no significant difference in the value of PSV, RI, and PI between malignancy and benignity group. In conclusion, color Doppler imaging has a potential role in the characterization of thyroid nodules as a supportive method for gray scale diagnosis

  5. Noticeable positive Doppler effect on optical bistability in an N-type active Raman gain atomic system

    International Nuclear Information System (INIS)

    Chang Zeng-Guang; Zhang Jing-Tao; Niu Yue-Ping; Gong Shang-Qing

    2012-01-01

    We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity. It is shown that the Doppler effect can greatly enhance the dispersion and thus create the bistable behaviour or greatly increase the bistable region, which has been known as the positive Doppler effect on optical bistability. In addition, we find that a positive Doppler effect can change optical bistability from the hybrid dispersion-gain type to a dispersive type

  6. Current Perspectives in Hyperbaric Physiology, Ultrasonic Doppler Bubble Detection, and Mass Spectrometry,

    Science.gov (United States)

    1979-12-28

    Doppler sound made by a bubble passing through the inson- ified volume blood vessel resembles a very sharp truncated whistle , chirp or click depending...the Doppler ultrasound , suffered the "slings and arrows of outrageous criticism" to borrow and beat a phrase. It is not appropriate to go into this

  7. Aircraft Wake Vortex Measurement with Coherent Doppler Lidar

    Directory of Open Access Journals (Sweden)

    Wu Songhua

    2016-01-01

    Full Text Available Aircraft vortices are generated by the lift-producing surfaces of the aircraft. The variability of near-surface conditions can change the drop rate and cause the cell of the wake vortex to twist and contort unpredictably. The pulsed Coherent Doppler Lidar Detection and Ranging is an indispensable access to real aircraft vortices behavior which transmitting a laser beam and detecting the radiation backscattered by atmospheric aerosol particles. Experiments for Coherent Doppler Lidar measurement of aircraft wake vortices has been successfully carried out at the Beijing Capital International Airport (BCIA. In this paper, the authors discuss the Lidar system, the observation modes carried out in the measurements at BCIA and the characteristics of vortices.

  8. Influence of the power level of an ultra-sonic system on dental cavity preparation Influência do nível de potência de um sistema de ultra-som em preparos cavitários

    Directory of Open Access Journals (Sweden)

    Érika Botelho Josgrilberg

    2007-12-01

    Full Text Available The aim of this study was to evaluate the shape of dental cavities made with the CVDentus® system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus® cylindrical bur (82142. The sample was divided into three groups: G1 - ultrasound with power II; G2 - ultrasound with power III; and G3 - ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during one minute in each dental preparation. The cavities were sectioned in the middle, allowing observation of the cavity’s profile with a magnifying glass, and width and depth measurement using the Leica Qwin program. The Kruskal-Wallis (p O objetivo deste estudo foi avaliar o formato dos preparos cavitários realizados com o sistema CVDentus® utilizando potências variadas do ultra-som. Uma cavidade padronizada foi realizada na face vestibular de 15 incisivos bovinos utilizando as pontas cilíndricas CVDentus® (82142. A amostra foi dividida em 3 grupos: G1 - ultra-som com potência II; G2 - ultra-som com potência III; e G3 - ultra-som com potência IV. Foi utilizada uma máquina padronizadora de preparos cavitários e o ultra-som foi aplicado durante 1 minuto em cada preparo. As cavidades foram seccionadas no centro, permitindo a visualização do perfil cavitário em uma lupa estereoscópica, e esse foi medido em largura e profundidade por meio do programa Leica Qwin. O teste estatístico Kruskal-Wallis (p < 0,05 e o método de Dunn demonstraram diferenças entre os formatos das cavidades produzidas com as potências III e IV. Entretanto, as cavidades realizadas com a potência III apresentaram dimensões semelhantes às da ponta utilizada. Concluiu-se que a potência indicada pelo fabricante (III é a mais adequada para uso do sistema CVDentus®.

  9. The UltraLightweight Technology for Research in Astronomy (ULTRA) Project

    Science.gov (United States)

    Twarog, B. A.; Anthony-Twarog, B. J.; Shawl, S. J.; Hale, R.; Taghavi, R.; Fesen, R.; Etzel, P. B.; Martin, R.; Romeo, R.

    2004-12-01

    The collaborative focus of four academic departments (Univ. of Kansas Aerospace Engineering, Univ. of Kansas Physics & Astronomy, San Diego State University Astronomy and Dartmouth College Astronomy) and a private industry partner (Composite Mirror Applications, Inc.-CMA, Inc.) is a three-year plan to develop and test UltraLightweight Technology for Research in Astronomy (ULTRA). The ULTRA technology, using graphite fiber composites to fabricate mirrors and telescope structures, offers a versatile and cost-effective tool for optical astronomy, including the economical fabrication and operation of telescopes ranging from small (1m or smaller) aperture for education and research to extremely large (30m+) segmented telescopes (ELTs). The specific goal of this NSF-funded three-year Major Research Instrumentation project is to design, build, and test a 1m-class optical tube assembly (OTA) and mirrors constructed entirely from composites. In the first year of the project, the team has built and is field-testing two 0.4m prototypes to validate the optical surfaces and figures of the mirrors and to test and refine the structural dynamics of the OTA. Preparation for design and construction of the 1m telescope is underway. When completed in late 2005, the ULTRA telescope will be operated remotely from Mt. Laguna Observatory east of San Diego, where it will undergo a period of intensive optical and imaging tests. A 0.4m prototype OTA with mirrors (12 kg total weight) will be on display at the meeting. Support of this work by NSF through grants AST-0320784 and AST-0321247, NASA grant NCC5-600, the University of Kansas, and San Diego State University is gratefully acknowledged.

  10. ANALISIS EFEK KECELAKAAN WATER INGRESS TERHADAP REAKTIVITAS DOPPLER TERAS RGTT200K

    Directory of Open Access Journals (Sweden)

    Zuhair Zuhair

    2015-03-01

    Full Text Available Dalam high temperature reactor, koefisien reaktivitas temperatur yang didesain negatif menjamin reaksi fisi dalam teras tetap berada di bawah kendali dan panas peluruhan tidak akan pernah melelehkan bahan bakar yang menyebabkan terlepasnya zat radioaktif ke lingkungan. Namun masuknya air (water ingress ke dalam teras reaktor akibat pecahnya tabung penukar panas generator uap, yang dikenal sebagai salah satu kecelakaan dasar desain, dapat mengintroduksi reaktivitas positif dengan potensi bahaya lainnya seperti korosi grafit dan kerusakan material struktur reflektor. Makalah ini akan menganalisis efek kecelakaan water ingress terhadap reaktivitas Doppler teras RGTT200K. Kapabilitas koefisien reaktivitas Doppler untuk mengkompensasi reaktivitas positif yang timbul selama kecelakaan water ingress akan diuji melalui serangkaian perhitungan dengan program MCNPX dan pustaka ENDF/B-VII untuk perubahan temperatur bahan bakar dari 800K hingga 1800K. Tiga opsi kernel bahan bakar UO2, ThO2/UO2 dan PuO2 dengan tiga model kisi bahan bakar pebble di teras reaktor diterapkan untuk kondisi water ingress dengan densitas air dari 0 hingga 1.000 kg/m3. Hasil perhitungan memperlihatkan koefisien reaktivitas Doppler tetap negatif untuk seluruh opsi bahan bakar yang dipertimbangkan bahkan untuk posibilitas water ingress yang besar. Efek water ingress lebih kuat pada model kisi dengan fraksi packing lebih rendah karena lebih banyak volume yang tersedia untuk air yang memasuki teras reaktor. Efek water ingress juga lebih kuat di teras uranium dibandingkan teras thorium dan plutonium sebagai konsekuensi dari fenomena Doppler dimana absorpsi neutron di daerah resonansi 238U lebih besar daripada 232Th dan 240Pu. Secara keseluruhan dapat disimpulkan bahwa, koefisien Doppler teras RGTT200K mampu mengkompensasi insersi reaktivitas yang diintroduksi oleh kecelakaan water ingress. Teras RGTT200K dengan bahan bakar UO2, ThO2/UO2 dan PuO2 dapat mempertahankan fitur keselamatan

  11. 21 CFR 177.2910 - Ultra-filtration membranes.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ultra-filtration membranes. 177.2910 Section 177... Components of Articles Intended for Repeated Use § 177.2910 Ultra-filtration membranes. Ultra-filtration membranes identified in paragraphs (a)(1), (a)(2), (a)(3), and (a)(4) of this section may be safely used in...

  12. 3D power Doppler ultrasound in early diagnosis of preeclampsia.

    Science.gov (United States)

    Neto, R Moreira; Ramos, J G L

    2016-01-01

    Preeclampsia is a known cause of maternal, fetal and neonatal morbidity and mortality. Thus, evaluation of the predicting value of comparing 3D power Doppler indices (3DPD) of uteroplacental circulation (UPC) in the first and second trimester in patients who developed preeclampsia (PE) and those who did not and testing the hypothesis that the parameters of vascularization and placenta flow intensity, as determined by three-dimensional ultrasound (3D), are different in normal pregnancies compared with preeclampsia, could be a suitable screening method. A prospective observational study using 3D power Doppler were performed to evaluate the placental perfusion in 96 pregnant women who came to do the ultrasound routine between 11 and 14 weeks. The placental vascular index (VI), flow index (FI), blood vessels and blood flow index (VFI) by three-dimensional Doppler histogram were calculated. All patients repeated the exam between 16 and 20 weeks. The outcome was scored as normal or preeclamptic. Placental vascular indices including VI, FI and VFI were significantly lower in preeclamptic placentas compared with controls in the study performed in the second trimester (ppower Doppler assessment of placental vascular indices in the second trimester has the potential to detect women at risk for subsequent development of PE. Copyright © 2015 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  13. Gestational trophoblastic neoplasia: efficacy of color doppler ultrasound

    International Nuclear Information System (INIS)

    Song, Sun Wha; Jee, Won Hee; Choe, Bo Young; Byun, Jae Young; Choi, Byung Gil; Shinn, Kyung Sub

    1997-01-01

    To evaluate the efficacy of color Doppler ultrasound (US) in the diagnosis of gestational trophoblastic neoplasia (GTN). Intralesional color flows and resistive index (RI) on color Doppler US were prospectively analyzed in 21 consecutive suspected GTN cases. RI of the intralesional artery was investigated on the basis of the presence or absence of mass and metastasis. Correlation between RI of intralesional artery and urinary β-hCG was also investigated. Intralesional color flows were identified in 15 patients with GTN. On operation, intralesional color flows were observed in one of two patients in whom the presence of completely necrotic tissue was confirmed. Intralesional color flows, however, were not detected in four patients who were proved not to be GTN sufferers. Sensitivity, specificity, accuracy, positive and negative predictive values, and accuracy were 100%, 83%, 95%, 94% and 100%, respectively. Significant correlation between RI of the intralesional artery and urinary β-hCG was not established (p=0.49, r=0.19). RI of this artery was not substantially different between groups with and without mass, and between groups with and without metastasis (p=0.32, p=0.82). The current study demonstrates that color Doppler US is a sensitive and useful method for the diagnosis of GTN

  14. Transcranial Doppler sonography in familial hemiplegic migraine

    International Nuclear Information System (INIS)

    Pierelli, F.; Pauri, F.; Cupini, L.M.; Fiermonte, G.; Rizzo, P.A.

    1991-01-01

    A patient affected by familial hemiplegic migraine underwent transcranial Doppler sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headachefree period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. The results indicate that during the attack in this familial hemiplegic migraine patient, a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, transcranial Doppler sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome. 13 refs., 1 figs., 1 tab

  15. Transcranial Doppler sonography in familial hemiplegic migraine

    Energy Technology Data Exchange (ETDEWEB)

    Pierelli, F.; Pauri, F.; Cupini, L.M.; Fiermonte, G.; Rizzo, P.A. (Universita la Sapienza, Roma (Italy))

    1991-02-01

    A patient affected by familial hemiplegic migraine underwent transcranial Doppler sonography twice: the first during a spontaneous attack with right hemiparesis and aphasia, the second during a headachefree period. During the attack the following haemodynamic changes were seen: (a) bilateral increase in the middle cerebral artery and anterior cerebral artery blood flow velocities (this increase was more pronounced on the left side), (b) decreased systo-diastolic ratio and pulsatility index on the right side, (c) increased systo-diastolic ratio and pulsatility index on the left side. The results indicate that during the attack in this familial hemiplegic migraine patient, a diffuse vasoconstriction of the basal cerebral arteries developed. Moreover, transcranial Doppler sonography data suggest that a prolonged vasoconstriction of the peripheral arterioles could play a role in determining the neurological symptoms in this syndrome. 13 refs., 1 figs., 1 tab.

  16. Void effects on BWR Doppler and void reactivity feedback

    International Nuclear Information System (INIS)

    Hsiang-Shou Cheng; Diamond, D.J.

    1978-01-01

    The significance of steam voids and control rods on the Doppler feedback in a gadolinia shimmed BWR is demonstrated. The importance of bypass voids when determining void feedback is also shown. Calculations were done using a point model, i.e., feedback was expressed in terms of reactivity coefficients which were determined for individual four-bundle configurations and then appropriately combined to yield reactor results. For overpower transients the inclusion of the void effect of control rods is to reduce Doppler feedback. For overpressurization transients the inclusion of the effect of bypass void wil increase the reactivity due to void collapse. (author)

  17. Sub-Doppler cooling in reduced-period optical lattice geometries

    International Nuclear Information System (INIS)

    Berman, P.R.; Raithel, G.; Zhang, R.; Malinovsky, V.S.

    2005-01-01

    It is shown that sub-Doppler cooling occurs in an atom-field geometry that can lead to reduced-period optical lattices. Four optical fields are combined to produce a 'standing wave' Raman field that drives transitions between two ground state sublevels. In contrast to conventional Sisyphus cooling, sub-Doppler cooling to zero velocity occurs when all fields are polarized in the same direction. Solutions are obtained using both semiclassical and quantum Monte Carlo methods in the case of exact two-photon resonance. The connection of the results with conventional Sisyphus cooling is established using a dressed state basis

  18. Quality-Controlled Wind Data from the Kennedy Space Center 915 Megahertz Doppler Radar Wind Profiler Network

    Science.gov (United States)

    Dryden, Rachel L.

    2011-01-01

    The National Aeronautics and Space Administration s (NASA) Kennedy Space Center (KSC) has installed a five-instrument 915-Megahertz (MHz) Doppler Radar Wind Profiler (DRWP) system that records atmospheric wind profile properties. The purpose of these profilers is to fill data gaps between the top of the KSC wind tower network and the lowest measurement altitude of the KSC 50-MHz DRWP. The 915-MHz DRWP system has the capability to generate three-dimensional wind data outputs from approximately 150 meters (m) to 6,000 m at roughly 15-minute (min) intervals. NASA s long-term objective is to combine the 915-MHz and 50-MHz DRWP systems to create complete vertical wind profiles up to 18,300 m to be used in trajectory and loads analyses of space vehicles and by forecasters on day-of-launch (DOL). This analysis utilizes automated and manual quality control (QC) processes to remove erroneous and unrealistic wind data returned by the 915-MHz DRWP system. The percentage of data affected by each individual QC check in the period of record (POR) (i.e., January to April 2006) was computed, demonstrating the variability in the amount of data affected by the QC processes. The number of complete wind profiles available at given altitude thresholds for each profiler in the POR was calculated and outputted graphically, followed by an assessment of the number of complete wind profiles available for any profiler in the POR. A case study is also provided to demonstrate the QC process on a day of a known weather event.

  19. Collapse and revival of the Doppler-Rabi oscillations of a moving atom in a cavity

    International Nuclear Information System (INIS)

    Kozlovskii, A. V.

    2008-01-01

    Collapse and revival of the Doppler-Rabi oscillations of a two-level atom moving in a cavity electromagnetic field are analyzed. The coupled atom-field dynamics are predicted accurately by numerical calculation and approximately by using the stationary phase approximation combined with the Poisson summation formula. The collapse and revival patterns are shown to be qualitatively different in the cases of moving atom and atom at rest. In particular, quantum revivals of Doppler-Rabi oscillations occur with a period determined by the Doppler shift of the atomic transition frequency. This regime of Doppler-Rabi oscillations requires that the Rabi frequency and the Doppler shift satisfy the condition Ω R D . Under the inverse relation, the collapse- revival phenomenon generally does not occur. It is shown that even a small amount of atom-cavity detuning eliminates collapse-revival behavior. The analysis is performed for both coherent and thermal cavity fields

  20. The Assessment of Left Ventricular Time-Varying Radius Using Tissue Doppler Imaging

    Directory of Open Access Journals (Sweden)

    Fardin Mirbolouk

    2012-03-01

    Full Text Available Background: Left ventricular twist/torsion is believed to be a sensitive indicator of systolic and diastolic performance. To obtain circumferential rotation using tissue Doppler imaging, we need to estimate the time-varying radius of the left ventricle throughout the cardiac cycle to convert the tangential velocity into angular velocity. Objectives: The aim of this study was to investigate accuracy of measured LV radius using tissue Doppler imaging throughout the cardiac cycle compared to two-dimensional (2D imaging. Methods: A total of 35 subjects (47±12 years old underwent transthoracic echocardiographic standard examinations. Left ventricular radius during complete cardiac cycle measured using tissue Doppler and 2D-imaging at basal and apical short axis levels. For this reason, the 2D-images and velocity-time data derived and transferred to a personal computer for off-line analysis. 2D image frames analyzed via a program written in the MATLAB software. Velocity-time data from anteroseptal at basal level (or anterior wall at apical level and posterior walls transferred to a spreadsheet Excel program for the radius calculations. Linear correlation and Bland-Altman analysis were calculated to assess the relationships and agreements between the tissue Doppler and 2D-measured radii throughout the cardiac cycle. Results: There was significant correlation between tissue Doppler and 2D-measured radii and the Pearson correlation coefficients were 0.84 to 0.97 (P<0.05. Bland-Altman analysis by constructing the 95% limits of agreement showed that the good agreements existed between the two methods. Conclusion: It can be concluded from our experience that the tissue Doppler imaging can reasonably estimate radius of the left ventricle throughout the cardiac cycle.

  1. A Doppler Radar System for Sensing Physiological Parameters in Walking and Standing Positions

    Directory of Open Access Journals (Sweden)

    Malikeh Pour Ebrahim

    2017-03-01

    Full Text Available Doppler radar can be implemented for sensing physiological parameters wirelessly at a distance. Detecting respiration rate, an important human body parameter, is essential in a range of applications like emergency and military healthcare environments, and Doppler radar records actual chest motion. One challenge in using Doppler radar is being able to monitor several patients simultaneously and in different situations like standing, walking, or lying. This paper presents a complete transmitter-receiver Doppler radar system, which uses a 4 GHz continuous wave radar signal transmission and receiving system, to extract base-band data from a phase-shifted signal. This work reports experimental evaluations of the system for one and two subjects in various standing and walking positions. It provides a detailed signal analysis of various breathing rates of these two subjects simultaneously. These results will be useful in future medical monitoring applications.

  2. Ophthalmic artery color Doppler ultrasonography in mild-to-moderate preeclampsia

    Energy Technology Data Exchange (ETDEWEB)

    Ayaz, Tunahan; Akansel, Gur. E-mail: gakansel@superonline.com; Hayirlioglu, Alper; Arslan, Arzu; Suer, Necdet; Kuru, Ihsan

    2003-06-01

    Objective: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. Methods: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. Results: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. Conclusion: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia.

  3. Identification of ultra-fine Ti-rich precipitates in V-Cr-Ti alloys irradiated below 300 deg. C by using positron CDB technique

    International Nuclear Information System (INIS)

    Fukumoto, Ken-ichi; Matsui, Hideki; Ohkubo, Hideaki; Tang, Zheng; Nagai, Yasuyoshi; Hasegawa, Masayuki

    2008-01-01

    Irradiation-induced Ti-rich precipitates in V-Ti and V-4Cr-4Ti alloys are studied by TEM and positron annihilation methods (positron lifetime, and coincidence Doppler broadening (CDB)). The characteristics of small defect clusters formed in V alloys containing Ti at irradiation temperatures below 300 deg. C have not been identified by TEM techniques. Strong interaction between vacancy and Ti solute atoms for irradiated V alloys containing Ti at irradiation temperatures from 220 to 350 deg. C are observed by positron lifetime measurement. The vacancy-multi Ti solute complexes in V-alloys containing Ti are definitely identified by using CDB measurement. It is suggested that ultra-fine Ti-rich precipitates or Ti segregation at periphery of dislocation loops are formed in V alloys containing Ti at irradiation temperatures below 300 deg. C

  4. Doppler Wind Lidar Measurements and Scalability to Space

    Data.gov (United States)

    National Aeronautics and Space Administration — Global measurements of wind speed and direction from Doppler wind lidars, if available, would significantly improve forecasting of severe weather events such as...

  5. Laser Doppler flowmetry for measurement of laminar capillary blood flow in the horse

    Science.gov (United States)

    Adair, Henry S., III

    1998-07-01

    Current methods for in vivo evaluation of digital hemodynamics in the horse include angiography, scintigraphy, Doppler ultrasound, electromagnetic flow and isolated extracorporeal pump perfused digit preparations. These techniques are either non-quantifiable, do not allow for continuous measurement, require destruction of the horse orare invasive, inducing non- physiologic variables. In vitro techniques have also been reported for the evaluation of the effects of vasoactive agents on the digital vessels. The in vitro techniques are non-physiologic and have evaluated the vasculature proximal to the coronary band. Lastly, many of these techniques require general anesthesia or euthanasia of the animal. Laser Doppler flowmetry is a non-invasive, continuous measure of capillary blood flow. Laser Doppler flowmetry has been used to measure capillary blood flow in many tissues. The principle of this method is to measure the Doppler shift, that is, the frequency change that light undergoes when reflected by moving objects, such as red blood cells. Laser Doppler flowmetry records a continuous measurement of the red cell motion in the outer layer of the tissue under study, with little or no influence on physiologic blood flow. This output value constitutes the flux of red cells and is reported as capillary perfusion units. No direct information concerning oxygen, nutrient or waste metabolite exchange in the surrounding tissue is obtained. The relationship between the flowmeter output signal and the flux of red blood cells is linear. The principles of laser Doppler flowmetry will be discussed and the technique for laminar capillary blood flow measurements will be presented.

  6. Inteligencias artificiales y ensayos ultrasónicos para la detección de defectos

    Directory of Open Access Journals (Sweden)

    Barrera Cardiel, Gerardo

    2001-06-01

    Full Text Available One of the most serious problems in the quality control of welded unions is the location, identification and classification of defects. As a solution to this problem, a technique for classification, applicable to welded unions done by electric arc welding as well as by friction, is proposed; it is based on ultrasonic signals. The neuronal networks proposed are Kohonen and Multilayer Perceptron, all in a virtual instrument environment. Currently the techniques most used in this field are: radiological analysis (X-rays and ultrasonic analysis (ultrasonic waves. The X-ray technique in addition to being dangerous requires highly specialized personnel and equipment, therefore its use is restricted. The ultrasonic technique, in spite of being one of the most used for detection of discontinuities, requires personnel with wide experience in the interpretation of ultrasonic signals; this is a timeconsuming process which necessarily increases its operation cost. The classification techniques that we propose turn out to be safe, reliable, inexpensive and easy to implement for the solution of this important problem.

    Uno de los problemas más serios dentro del análisis de la calidad de uniones soldadas es la localización e identificación de los defectos que se producen en la elaboración de dichas uniones. Como solución a este problema se propone la técnica de clasificación, por medio de la técnica de redes neuronales, para la localización e identificación en línea de defectos, tanto en piezas unidas por las técnicas convencionales (aporte de material-arco eléctrico como por fricción, entre otras, mediante el uso de patrones de señales ultrasónicas. Las redes neuronales propuestas son: Kohonen y Perceptron por Multicapas, todo en un ambiente de instrumentación virtual. Actualmente, las técnicas más utilizadas en este campo son las basadas en el análisis radiológico (aplicación de rayos X y en el análisis ultrasónico (aplicaci

  7. Deep vein thrombosis of lower extremity: What is the most important finding in duplex Doppler sonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Koh, Byung Hee; Cho, On Koo; Rhim, Hyun Chul; Seo, Heung Suk; Hahm, Chang Kok; Kwak, Jin Young [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    1993-12-15

    The positive findings of deep vein thrombosis on duplex Doppler ultrasonography such as intraluminal clot,non-compressibility of the venous lumen and abnormal or absent Doppler shift signal are well known. However, relatively hypoechoic thrombus is not always seen in sonography, and the vein is frequently compressible in partial thrombosis. In order to evaluate the most common and important findings of deep vein thrombosis, we analysed the findings at duplex Doppler ultrasound in 19 patients and compared the results with those of contrast venography in 11 patients. Duplex Doppler ultrasound examination of the common femoral and popliteal veins was performed for one extremity in 14 patients, and for both extremities in 5 (total 24 extremities). Contrast venography was performed for one extremity in 7 patients, and for both sides in 4 (total 15 extremities).Thrombosis was seen in 45.8%, non-compressibility of lumen in 75%, absent or decreased Doppler signal from common femoral vein in 95.8%. Thrombosis was seen in 41.7%, non-compressibility of lumen in 70.8%, absent or decreased Doppler shift signal from popliteal vein in 95.8%. We conclude that abnormal or absent Doppler shift signal is the most sensitive and important finding of the deep vein thrombosis

  8. Verification of MC{sup 2}-3 Doppler Sample Models in ZPPR-15 D Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Jae; Hartanto, Donny; Kim, Sang Ji [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    In this paper, the change of reaction rate and broadened cross section were estimated by as-built MCNP models for metallic uranium sample in ZPPR-15D using ENDF/B-VII.0 library, and the results were compared with deterministic calculations provided in previous work. The Doppler broadening is an instant feedback mechanism that improves safety and stability for both thermal and fast reactors. Therefore, the accuracy of Doppler coefficient becomes an important parameter in reactor design as well as in the safety analysis. The capability of the Doppler worth calculation by a modern computer code suites such as MC2-3 and DIF3DVARIANT, has been validated against the Zero Power Physics Reactor-15 (ZPPR-15) Doppler worth measurement experiments. For the same experiments, our previous work suggested four different MC2-3 Doppler sample models for enhanced accuracy, which are combinations of heterogeneous models and the super cell approach. The MOC and MOC-SPC models showed the smallest error in estimating the U-238 total cross section of Doppler sample N-11, and the Doppler broadening effects are well applied to the cross section compared to other two models, HOM and SPC. The effects of the super cell approach can be hardly seen, since the broadened cross section is almost the same with and without the super cell approach. Comparing the transition of reaction density, MOC and MOC-SPC models also show similar behavior as MCNP's with minor errors. As a conclusion, we could obtain more consistent broadened cross section as well as reaction density transition by providing heterogeneous models from MC2-3's MOC module.

  9. Uncertainty of Doppler reactivity worth due to uncertainties of JENDL-3.2 resonance parameters

    Energy Technology Data Exchange (ETDEWEB)

    Zukeran, Atsushi [Hitachi Ltd., Hitachi, Ibaraki (Japan). Power and Industrial System R and D Div.; Hanaki, Hiroshi; Nakagawa, Tuneo; Shibata, Keiichi; Ishikawa, Makoto

    1998-03-01

    Analytical formula of Resonance Self-shielding Factor (f-factor) is derived from the resonance integral (J-function) based on NR approximation and the analytical expression for Doppler reactivity worth ({rho}) is also obtained by using the result. Uncertainties of the f-factor and Doppler reactivity worth are evaluated on the basis of sensitivity coefficients to the resonance parameters. The uncertainty of the Doppler reactivity worth at 487{sup 0}K is about 4 % for the PNC Large Fast Breeder Reactor. (author)

  10. Spacecraft Doppler tracking with possible violations of LLI and LPI: a theoretical modeling

    International Nuclear Information System (INIS)

    Deng Xue-Mei; Xie Yi

    2014-01-01

    Currently two-way and three-way spacecraft Doppler tracking techniques are widely used and play important roles in control and navigation of deep space missions. Starting from a one-way Doppler model, we extend the theory to two-way and three-way Doppler models by making them include possible violations of the local Lorentz invariance (LLI) and the local position invariance (LPI) in order to test the Einstein equivalence principle, which is the cornerstone of general relativity and all other metric theories of gravity. After taking the finite speed of light into account, which is the so-called light time solution (LTS), we make these models depend on the time of reception of the signal only for practical convenience. We find that possible violations of LLI and LPI cannot affect two-way Doppler tracking under a linear approximation of LTS, although this approximation is sufficiently good for most cases in the solar system. We also show that, in three-way Doppler tracking, possible violations of LLI and LPI are only associated with two stations, which suggests that it is better to set the stations at places with significant differences in velocities and gravitational potentials to obtain a high level of sensitivity for the tests

  11. High-frequency dual mode pulsed wave Doppler imaging for monitoring the functional regeneration of adult zebrafish hearts

    OpenAIRE

    Kang, Bong Jin; Park, Jinhyoung; Kim, Jieun; Kim, Hyung Ham; Lee, Changyang; Hwang, Jae Youn; Lien, Ching-Ling; Shung, K. Kirk

    2015-01-01

    Adult zebrafish is a well-known small animal model for studying heart regeneration. Although the regeneration of scars made by resecting the ventricular apex has been visualized with histological methods, there is no adequate imaging tool for tracking the functional recovery of the damaged heart. For this reason, high-frequency Doppler echocardiography using dual mode pulsed wave Doppler, which provides both tissue Doppler (TD) and Doppler flow in a same cardiac cycle, is developed with a 30 ...

  12. Wayside Bearing Fault Diagnosis Based on a Data-Driven Doppler Effect Eliminator and Transient Model Analysis

    Science.gov (United States)

    Liu, Fang; Shen, Changqing; He, Qingbo; Zhang, Ao; Liu, Yongbin; Kong, Fanrang

    2014-01-01

    A fault diagnosis strategy based on the wayside acoustic monitoring technique is investigated for locomotive bearing fault diagnosis. Inspired by the transient modeling analysis method based on correlation filtering analysis, a so-called Parametric-Mother-Doppler-Wavelet (PMDW) is constructed with six parameters, including a center characteristic frequency and five kinematic model parameters. A Doppler effect eliminator containing a PMDW generator, a correlation filtering analysis module, and a signal resampler is invented to eliminate the Doppler effect embedded in the acoustic signal of the recorded bearing. Through the Doppler effect eliminator, the five kinematic model parameters can be identified based on the signal itself. Then, the signal resampler is applied to eliminate the Doppler effect using the identified parameters. With the ability to detect early bearing faults, the transient model analysis method is employed to detect localized bearing faults after the embedded Doppler effect is eliminated. The effectiveness of the proposed fault diagnosis strategy is verified via simulation studies and applications to diagnose locomotive roller bearing defects. PMID:24803197

  13. Outlier Detection in GNSS Pseudo-Range/Doppler Measurements for Robust Localization

    Directory of Open Access Journals (Sweden)

    Salim Zair

    2016-04-01

    Full Text Available In urban areas or space-constrained environments with obstacles, vehicle localization using Global Navigation Satellite System (GNSS data is hindered by Non-Line Of Sight (NLOS and multipath receptions. These phenomena induce faulty data that disrupt the precise localization of the GNSS receiver. In this study, we detect the outliers among the observations, Pseudo-Range (PR and/or Doppler measurements, and we evaluate how discarding them improves the localization. We specify a contrario modeling for GNSS raw data to derive an algorithm that partitions the dataset between inliers and outliers. Then, only the inlier data are considered in the localization process performed either through a classical Particle Filter (PF or a Rao-Blackwellization (RB approach. Both localization algorithms exclusively use GNSS data, but they differ by the way Doppler measurements are processed. An experiment has been performed with a GPS receiver aboard a vehicle. Results show that the proposed algorithms are able to detect the ‘outliers’ in the raw data while being robust to non-Gaussian noise and to intermittent satellite blockage. We compare the performance results achieved either estimating only PR outliers or estimating both PR and Doppler outliers. The best localization is achieved using the RB approach coupled with PR-Doppler outlier estimation.

  14. Spectral color Doppler in the diagnosis and follow-up of Graves' disease

    International Nuclear Information System (INIS)

    Sponza, Massimo; Bertolotto, Michele; Ricci, Claudio; Fabris, Bruno; Armini, Lorenzo

    1997-01-01

    Hyperthyroidism in Graves' disease is caused by the presence of circulating autoantibodies to the THS receptors on the thyroid cells. Thyroid-suppression therapy prevents hormone production directly, without affecting the pathogenetic process. They performed color Doppler US of the thyroid gland and pulsed Doppler analysis of thyroid artery flow in 21 patients with Graves' disease before and during medical treatment. US results were compared with those of a control group of 40 healthy subjects and correlated with the values of thyroid hormones, TSH and thyroid microsomal and thyroglobulin antibodies. The thyroid gland was hypo vascularized in the control group. Pulsed Doppler examination of the thyroid arteries exhibited peak systolic velocity of PSV 20 ± 4 cm/s, diastolic velocity of 8 ± 1 cm/s, and resistive index of 0.60 ± 0.04. The thyroid gland of Graves' disease patients was hyper vascularized. Pulsed Doppler examination of the thyroid arteries exhibited peak systolic velocity (PSV = 51 ± 12 cm/s), end diastolic velocity (VD = 15 ± 4 cm/s) and resistive index (RI = 0.71 ± 0.04) significantly higher than in normal subjects (p < 0.001). Circulating thyroid hormones and flow parameters normalized after 6-8 months of medical therapy (PSV = 20 ± 6 cm/s, VD = 9 ± 3 cm(s, RI = 0.58 ± 0.07). The color Doppler patterns normalized only in a patient with normal TSH and antibodies. Sampling of the thyroid arteries proved more repeatable than sampling of parenchymal vessels

  15. Effect of Casmo-5 cross-section data and doppler temperature definitions on LWR reactivity initiated accidents - 166

    International Nuclear Information System (INIS)

    Grandi, G.; Smith, K.; Xu, Z.; Rhodes, J.

    2010-01-01

    During LWR Reactivity Initiated Accidents (RIA), the accurate evaluation of the Doppler reactivity feedback depends on the Doppler coefficient computed by the lattice physics code (e.g. CASMO-5), and on the effective Doppler temperature computed by the transient code (e.g. SIMULATE-3K) using the non-uniform intra-pellet temperature profile. CASMO-5 has many new features compared with its predecessor. Among them, the replacement of the L-library (based primarily on ENDF/B IV data) by the latest available nuclear data (ENDF/B VII.0), and the Monte Carlo based resonance elastic scattering model to overcome deficiencies in NJOY modeling have a significant impact on the fuel temperature coefficient, and hence on LWR RIA. The Doppler temperature effect in thermal reactors is driven by the 238 U absorption. The different effective Doppler temperature definitions, available in the literature, try to capture the considerable self-shielding of the 238 U absorption that occurs in the pellet surface by defining an appropriate fuel temperature to compute cross-sections. In this work, we investigate the effect of the nuclear data generated by CASMO-5 on RIA, as well as the impact of different effective Doppler temperature definitions, including one proposed by the authors. It is concluded: 1) LWR RIA evaluated using CASMO-5 cross section data will be milder because the energy released is ∼10% smaller; 2) the prompt enthalpy rise is barely affected by the choice of the Doppler temperature definition; and 3) the peak fuel enthalpy is affected by the choice of the Doppler temperature definition, the under-prediction of the Doppler reactivity by the 'NEA' Doppler temperature results in a conservative estimate of the peak fuel enthalpy. (authors)

  16. Power Doppler sonography and ultrasound contrast agent in assessing rheumatoid synovitis

    Directory of Open Access Journals (Sweden)

    F. Salaffi

    2011-09-01

    Full Text Available Pannus formation is a fundamental event in the pathogenesis of rheumatoid arthritis and its hypervascularisation seems to be crucial to the development of joint damage. High-resolution greyscale ultrasonography is a safe, quick, and inexpensive imaging tool that allows an accurate detection of even minimal morphostructural changes in patients with rheumatoid arthritis, including joint effusion, thickening of synovial membrane and bone erosions. More recently, power Doppler sonography has proved to be a reliable tool for semiquantitative assessment of the vascularity of the synovial tissue. The contrast-enhanced power Doppler sonography seems to be a helpful adjunct in assessing synovitis and the therapeutic response to the different therapies in patients with rheumatoid arthritis. The aim of this radiological vignette was to show a representative example of use of power Doppler sonography with contrast agent in assessing rheumatoid synovitis.

  17. Pulsed and Color Doppler Sonographic Findings of Penile Mondor' Disease

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hye Yeon; Chung, Dong Jin; Kim, Kum Won; Hwang, Cheol Mog [University of Konyang School of Medicine, Daejeon (Korea, Republic of)

    2008-04-15

    Penile Mondor's disease is a rare disease that's characterized by thrombosis in the dorsal vein of the penis. Doppler ultrasonography (US) clearly visualizes dorsal vein thrombosis and the associated hemodynamic alterations. Previous studies have demonstrated the typical color Doppler US findings of superficial dorsal vein thrombosis without the flow signals in this area, yet this is insufficient to understand the hemodynamics in penile Mondor's disease. We report here for the first time a cavernosal artery flow signal pattern in a penile Mondor's disease patient, in addition to its previously reported classic US findings. In conclusion, the Doppler US findings of thrombus without blood flow in the superficial dorsal vein and the low-flow, high resistance in the cavernosal artery may be suggestive of penile Mondor's disease.

  18. Evaluation of renal allograft rejection by Doppler sonography and MR imaging

    International Nuclear Information System (INIS)

    Steinberg, H.V.; Nelson, R.C.; Murphy, F.B.; Baumgartner, B.R.; Bourke, E.; Delaney, V.B.; Whelchel, J.B.; Bernardino, M.E.

    1986-01-01

    The authors prospectively studies the efficacy of Doppler sonography and MR imaging in evaluating renal allografts, with specific attention to transplant rejection. Based on study findings, we were unable to make a statement with respect to the appearance or accuracy of diagnosing cyclosporin toxicity or acute tubular necrosis by either modality due to concomitant rejection in the few patients so afflicted. Moreover, the ability to predict and diagnose the presence or absence of allograft rejection was not affected by different serum creatinine values. Most important, however, Doppler sonography was shown to be superior to MR imaging in evaluating for allograft rejection, as evidenced by its higher sensitivity (100% vs. 71%), specificity (88% vs. 75%), and accuracy (96% vs. 73%). Thus, because of its low cost and ease of accessibility, Doppler sonography should become the primary modality for renal transplant screening

  19. Discrimination between pleural thickening and minimal pleural effusion using color Doppler chest ultrasonography

    Directory of Open Access Journals (Sweden)

    Ali A. Hasan

    2013-07-01

    Conclusions: Application of color Doppler examination increases the accuracy of real time chest ultrasound to discriminate pleural thickening from minimal pleural effusion and hence color Doppler examination proved to be a useful diagnostic tool to real-time gray-scale ultrasound for diagnosis of minimal pleural effusion.

  20. Doppler broadening measurements in FRX-C/LSM

    International Nuclear Information System (INIS)

    Baron, M.H.; Chrien, R.E.

    1989-01-01

    Measurements obtained in situ during field reversed configuration (FRC) formation show that the Doppler broadening ion temperature T CV is larger by a factor of two or more than the ion temperature T i derived from pressure balance and Thomson scattering. After a time comparable to an ion-ion equilibrium time, T CV and T i come into agreement with each other. An exception to this picture occurs in the lowest fill pressure condition (2 mtorr), for which T CV > T i is maintained throughout the FRC lifetime. Earlier Doppler broadening measurements in FRX-B and FRX-C also showed persistent, anomalously high T CV at low fill pressure. The initially high values of T CV are probably caused by convective motion generated by the radial implosion. The low fill pressure results suggest an enhanced ohmic power input to the carbon ions. 7 refs., 3 figs

  1. Portal blood flow volume measurement in schistosomal patients: evaluation of Doppler ultrasonography reproducibility

    International Nuclear Information System (INIS)

    Leao, Alberto Ribeiro de Souza; Santos, Jose Eduardo Mourao; Moulin, Danilo Sales; Shigueoka, David Carlos; D'Ippolito, Giuseppe; Colleoni, Ramiro

    2008-01-01

    Objective: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. Materials and methods: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearson's correlation coefficient. Results: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearson's correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). Conclusion: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement. (author)

  2. Portal blood flow volume measurement in schistosomal patients: evaluation of Doppler ultrasonography reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Alberto Ribeiro de Souza; Santos, Jose Eduardo Mourao; Moulin, Danilo Sales; Shigueoka, David Carlos; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Escola Paulista de Medicina. Dept. de Diagnostico por Imagem]. E-mail: ar.leao@uol.com.br; Colleoni, Ramiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Escola Paulista de Medicina. Dept. de Gastroenterologia

    2008-09-15

    Objective: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. Materials and methods: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearson's correlation coefficient. Results: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearson's correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). Conclusion: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement. (author)

  3. Changes in waveform on hepatic venous doppler in patients with chronic hepatic B: Correlation with histologic findings

    International Nuclear Information System (INIS)

    Ko, Joon Seok; Kim, Hak Soo; Chung, Dong Hae

    2001-01-01

    To evaluate changes of the waveform of the hepatic vein on doppler ultrasound (US) in patients with chronic hepatic B and to correlate them with histologic findings. Thirty three patients with chronic hepatic B were prospectively examined with doppler US, and liver biopsy was done at the same time. The right hepatic vein was examined on doppler US, and a liver biopsy was performed in the right lobe of the liver. Doppler waveform was considered abnormal if it showed either reduction in the amplitude of phasic oscillation without the reversed flow phase or the presence of completely flow. Specimens obtained from the biopsy were classified according to the predetermined histologic scoring criteria. It was technically possible to performed Doppler US of the right hepatic vein and liver biopsy simultaneously in all thirty three patients. Waveforms of the right hepatic vein were abnormal in fourteen (42.4%), biphasic in 12 (36.4%) and flat in two (6.0%) patients. Only the steatosis exhibited statistically significant correlation between changes of doppler waveform (p,0.05) of the normal and abnormal groups. Doppler US patterns of the hepatic vein in chronic hepatitis B were different from those of the normal group. The abnormal flow pattern on hepatic venous doppler appeared to be mainly influenced by the intrahepatic fat deposition rather than the degree of fibrosis.

  4. ULTRA-LIGHTWEIGHT CEMENT

    International Nuclear Information System (INIS)

    Fred Sabins

    2001-01-01

    The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter

  5. Power spectral density of velocity fluctuations estimated from phase Doppler data

    OpenAIRE

    Jicha Miroslav; Lizal Frantisek; Jedelsky Jan

    2012-01-01

    Laser Doppler Anemometry (LDA) and its modifications such as PhaseDoppler Particle Anemometry (P/DPA) is point-wise method for optical nonintrusive measurement of particle velocity with high data rate. Conversion of the LDA velocity data from temporal to frequency domain – calculation of power spectral density (PSD) of velocity fluctuations, is a non trivial task due to nonequidistant data sampling in time. We briefly discuss possibilities for the PSD estimation and specify limitations caused...

  6. Malformação arteriovenosa uterina após doença trofoblástica gestacional Uterine arteriovenous malformation after gestational trophoblastic disease

    Directory of Open Access Journals (Sweden)

    Paulo Belfort

    2006-02-01

    Full Text Available OBJETIVO: investigar a presença e resultados de malformações vasculares uterinas (MAVU após doença trofoblástica gestacional (DTG. MÉTODOS: estudo retrospectivo com inclusão de casos diagnosticados entre 1987 e 2004; 2764 pacientes após DTG foram acompanhadas anualmente com ultra-sonografia transvaginal e Doppler colorido no Centro de Neoplasia Trofoblástica Gestacional da Santa Casa da Misericórdia (Rio de Janeiro, RJ, Brasil. Sete pacientes tiveram diagnóstico final de MAVU baseado em análise ultra-sonográfica - índice de pulsatilidade (IP, índice de resistência (IR e velocidade sistólica máxima (VSM - e achados de imagens de ressonância nuclear magnética (RNM. Dosagens negativas de beta-hCG foram decisivas para estabelecer o diagnóstico diferencial com DTG recidivante. RESULTADOS: a incidência de MAVU após DTG foi 0,2% (7/2764. Achados ultra-sonográficos de MAVU: IP médio de 0,44±0,058 (extremos: 0,38-0,52; IR médio de 0,36±0,072 (extremos: 0,29-0,50; VSM média de 64,6±23,99 cm/s (extremos: 37-96. A imagem de RNM revelou útero aumentado, miométrio heterogêneo, espaços vasculares tortuosos e vasos parametriais com ectasia. A apresentação clínica mais comum foi hemorragia transvaginal, presente em 52,7% (4/7 dos casos. Tratamento farmacológico com 150 mg de acetato de medroxiprogesterona foi empregado para controlar a hemorragia, após a estabilização hemodinâmica. Permanecem as pacientes em seguimento, assintomáticas até hoje. Duas pacientes engravidaram com MAVU, com gestações e partos exitosos. CONCLUSÃO: presente sangramento transvaginal em pacientes com beta-hCG negativo e história de DTG, deve-se considerar a possibilidade de MAVU e solicitar avaliação ultra-sonográfica com dopplervelocimetria. O tratamento conservador é a melhor opção na maioria dos casos de MAVU pós-DTG.PURPOSE: to investigate the presence and outcome of uterinevascular malformations (UVAM after gestational

  7. Thermal Design for a Diffraction-Limited Doppler Spectrometer

    Data.gov (United States)

    National Aeronautics and Space Administration — The Univ. of Notre Dame is building a new high-resolution spectrometer named “iLocater” to achieve unprecedented radial velocity (RV) precision for stellar Doppler...

  8. Doppler-broadening of positron annihilation in a biological environment

    International Nuclear Information System (INIS)

    Torrisi, L.; La Mela, C.; Catania, Univ.

    1997-01-01

    The aim of this study was to investigate the Doppler effect of the 511 keV γ peak from positron annihilation in biological matter: The broadening of the annihilation peak is due to positron annihilation with electrons that have high momentum. In aqueous solutions annihilation depends on the temperature and it is linked positronium formation. Measurements in vivo, on human brain, were taken during the diagnosis of positron emission tomography (PET) on healthy patients by injecting them with the beta emitter of short lifetime 18F . The Doppler-broadening in biological tissues rich in water content decreased significantly compared to biological solutions and water

  9. Characterisation of baroreflex sensitivity of recreational ultra-endurance athletes.

    Science.gov (United States)

    Foulds, Heather J A; Cote, Anita T; Phillips, Aaron A; Charlesworth, Sarah A; Bredin, Shannon S D; Burr, Jamie F; Drury, Chipman Taylor; Ngai, Shirley; Fougere, Renee J; Ivey, Adam C; Warburton, Darren E R

    2014-01-01

    Altered autonomic function has been identified following ultra-endurance event participation among elite world-class athletes. Despite dramatic increases in recreational athlete participation in these ultra-endurance events, the physiological effects on these athletes are less known. This investigation sought to characterise changes in surrogate measures of autonomic function: heart rate variability (HRV), blood pressure variability (BPV) and baroreceptor sensitivity (BRS) following ultra-endurance race participation. Further, we sought to compare baseline measures among ultra-endurance athletes and recreationally active controls not participating in the ultra-endurance race. Recreational ultra-endurance athletes (n = 25, 44.6 ± 8.2 years, 8 females) and recreationally active age, sex and body mass index matched controls (n = 25) were evaluated. Measurements of HRV, BPV and BRS were collected pre- and post-race for recreational ultra-endurance athletes and at baseline, for recreationally active controls. Post-race, ultra-endurance athletes demonstrated significantly greater sympathetic modulation [low frequency (LF) power HRV: 50.3 ± 21.6 normalised units (n.u.) to 65.9 ± 20.4 n.u., p = 0.01] and significantly lower parasympathetic modulation [high frequency (HF) power HRV: 45.0 ± 22.4 n.u. to 23.9 ± 13.1 n.u., p HRV and BPV measures. Recreational ultra-endurance athletes experienced increased sympathetic tone and declines in BRS post-race, similar to previously reported elite world-class ultra-endurance athletes, though still within normal population ranges.

  10. Optical Doppler tomography based on a field programmable gate array

    DEFF Research Database (Denmark)

    Larsen, Henning Engelbrecht; Nilsson, Ronnie Thorup; Thrane, Lars

    2008-01-01

    We report the design of and results obtained by using a field programmable gate array (FPGA) to digitally process optical Doppler tomography signals. The processor fits into the analog signal path in an existing optical coherence tomography setup. We demonstrate both Doppler frequency and envelope...... extraction using the Hilbert transform, all in a single FPGA. An FPGA implementation has certain advantages over general purpose digital signal processor (DSP) due to the fact that the processing elements operate in parallel as opposed to the DSP. which is primarily a sequential processor....

  11. Doppler measurements of the ionosphere on the occasion of the Apollo-Soyuz test project. Part 1: Computer simulation of ionospheric-induced Doppler shifts

    Science.gov (United States)

    Grossi, M. D.; Gay, R. H.

    1975-01-01

    A computer simulation of the ionospheric experiment of the Apollo-Soyuz Test Project (ASTP) was performed. ASTP is the first example of USA/USSR cooperation in space and is scheduled for summer 1975. The experiment consists of performing dual-frequency Doppler measurements (at 162 and 324 MHz) between the Apollo Command Service Module (CSM) and the ASTP Docking Module (DM), both orbiting at 221-km height and at a relative distance of 300 km. The computer simulation showed that, with the Doppler measurement resolution of approximately 3 mHz provided by the instrumentation (in 10-sec integration time), ionospheric-induced Doppler shifts will be measurable accurately at all times, with some rare exceptions occurring when the radio path crosses regions of minimum ionospheric density. The computer simulation evaluated the ability of the experiment to measure changes of columnar electron content between CSM and DM (from which horizontal gradients of electron density at 221-km height can be obtained) and to measure variations in DM-to-ground columnar content (from which an averaged columnar content and the electron density at the DM can be deduced, under some simplifying assumptions).

  12. Sparse Representation Based Range-Doppler Processing for Integrated OFDM Radar-Communication Networks

    Directory of Open Access Journals (Sweden)

    Bo Kong

    2017-01-01

    Full Text Available In an integrated radar-communication network, multiuser access techniques with minimal performance degradation and without range-Doppler ambiguities are required, especially in a dense user environment. In this paper, a multiuser access scheme with random subcarrier allocation mechanism is proposed for orthogonal frequency division multiplexing (OFDM based integrated radar-communication networks. The expression of modulation Symbol-Domain method combined with sparse representation (SR for range-Doppler estimation is introduced and a parallel reconstruction algorithm is employed. The radar target detection performance is improved with less spectrum occupation. Additionally, a Doppler frequency detector is exploited to decrease the computational complexity. Numerical simulations show that the proposed method outperforms the traditional modulation Symbol-Domain method under ideal and realistic nonideal scenarios.

  13. The relationship between VHF radar auroral backscatter amplitude and Doppler velocity: a statistical study

    Directory of Open Access Journals (Sweden)

    B. A. Shand

    Full Text Available A statistical investigation of the relationship between VHF radar auroral backscatter intensity and Doppler velocity has been undertaken with data collected from 8 years operation of the Wick site of the Sweden And Britain Radar-auroral Experiment (SABRE. The results indicate three different regimes within the statistical data set; firstly, for Doppler velocities <200 m s–1, the backscatter intensity (measured in decibels remains relatively constant. Secondly, a linear relationship is observed between the backscatter intensity (in decibels and Doppler velocity for velocities between 200 m s–1 and 700 m s–1. At velocities greater than 700 m s–1 the backscatter intensity saturates at a maximum value as the Doppler velocity increases. There are three possible geophysical mechanisms for the saturation in the backscatter intensity at high phase speeds: a saturation in the irregularity turbulence level, a maximisation of the scattering volume, and a modification of the local ambient electron density. There is also a difference in the dependence of the backscatter intensity on Doppler velocity for the flow towards and away from the radar. The results for flow towards the radar exhibit a consistent relationship between backscatter intensity and measured velocities throughout the solar cycle. For flow away from the radar, however, the relationship between backscatter intensity and Doppler velocity varies during the solar cycle. The geometry of the SABRE system ensures that flow towards the radar is predominantly associated with the eastward electrojet, and flow away is associated with the westward electrojet. The difference in the backscatter intensity variation as a function of Doppler velocity is attributed to asymmetries between the eastward and westward electrojets and the geophysical parameters controlling the backscatter amplitude.

  14. The relationship between VHF radar auroral backscatter amplitude and Doppler velocity: a statistical study

    Directory of Open Access Journals (Sweden)

    B. A. Shand

    1996-08-01

    Full Text Available A statistical investigation of the relationship between VHF radar auroral backscatter intensity and Doppler velocity has been undertaken with data collected from 8 years operation of the Wick site of the Sweden And Britain Radar-auroral Experiment (SABRE. The results indicate three different regimes within the statistical data set; firstly, for Doppler velocities <200 m s–1, the backscatter intensity (measured in decibels remains relatively constant. Secondly, a linear relationship is observed between the backscatter intensity (in decibels and Doppler velocity for velocities between 200 m s–1 and 700 m s–1. At velocities greater than 700 m s–1 the backscatter intensity saturates at a maximum value as the Doppler velocity increases. There are three possible geophysical mechanisms for the saturation in the backscatter intensity at high phase speeds: a saturation in the irregularity turbulence level, a maximisation of the scattering volume, and a modification of the local ambient electron density. There is also a difference in the dependence of the backscatter intensity on Doppler velocity for the flow towards and away from the radar. The results for flow towards the radar exhibit a consistent relationship between backscatter intensity and measured velocities throughout the solar cycle. For flow away from the radar, however, the relationship between backscatter intensity and Doppler velocity varies during the solar cycle. The geometry of the SABRE system ensures that flow towards the radar is predominantly associated with the eastward electrojet, and flow away is associated with the westward electrojet. The difference in the backscatter intensity variation as a function of Doppler velocity is attributed to asymmetries between the eastward and westward electrojets and the geophysical parameters controlling the backscatter amplitude.

  15. Hepatic vein Doppler waveform in patients with diffuse fatty infiltration of the liver

    International Nuclear Information System (INIS)

    Oguzkurt, Levent; Yildirim, Tulin; Torun, Dilek; Tercan, Fahri; Kizilkilic, Osman; Niron, E. Alp

    2005-01-01

    Objective: To determine the incidence of abnormal hepatic vein Doppler waveform in patients with diffuse fatty infiltration of the liver (FIL). Materials and methods: In this prospective study, 40 patients with diffuse FIL and 50 normal healthy adults who served as control group underwent hepatic vein (HV) Doppler ultrasonography. The patients with the diagnosis of FIL were 23 men (57.5%) and 17 women aged 30-62 years (mean age ± S.D., 42 ± 12 years). Subjects in the control group were 27 men (54%) and 23 women aged 34-65 years (mean age ± S.D., 45 ± 14 years). The diagnosis of FIL was confirmed with computed tomography density measurements. The waveforms of HV were classified into three groups: regular triphasic waveform, biphasic waveform without a reverse flow, and monophasic or flat waveform. Etiological factors for FIL were diabetes mellitus (DM), hyperlipidemia and obesity (body mass index > 25). Serum lipid profile was obtained from all the patients with FIL. Results: Seventeen of the 40 patients (43%) with FIL had an abnormal HV Doppler waveform, whereas only one of the 50 (2%) healthy subjects had an abnormal waveform. The difference in the distribution of normal Doppler waveform pattern between the patients and the control group was significant (P 0.05). There was not any correlation between the degree of fat infiltration and the hepatic vein waveform pattern (P = 0.60). Conclusion: Patients with fatty liver has a high rate of an abnormal hepatic vein Doppler waveform pattern which can be biphasic or monophasic. We could not find a relation between the etiological factors for FIL and the occurrence of an abnormal HV Doppler waveform

  16. Doppler Sonographic Evaluation of Venogenic Extremity Swellings ...

    African Journals Online (AJOL)

    2017-09-14

    Sep 14, 2017 ... potentially lead to many complications including life-threatening pulmonary arterial thrombosis. Screening and confirmation ... and exclusion of acute lower extremity DVT. Duplex ultrasound is considered as the ... this study evaluates the role of Doppler sonography in the clinical management of suspected.

  17. [Postpartal ovarian thrombophlebitis. Value of Doppler ultrasonograph y].

    Science.gov (United States)

    Renaud-Giono, A; Giraud, J R; Poulain, P; Proudhon, J F; Grall, J Y; Moquet, P Y; Darnault, J P

    1996-01-01

    Thrombophlebitis of the ovarian vein is a well recognized but uncommon complication during the postpartum period. We report a small series and emphasize the contribution of color Doppler and the basic therapeutic measures.

  18. 7 CFR 58.144 - Pasteurization or ultra-pasteurization.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pasteurization or ultra-pasteurization. 58.144 Section... Service 1 Operations and Operating Procedures § 58.144 Pasteurization or ultra-pasteurization. When pasteurization or ultra-pasteurization is intended or required, or when a product is designated “pasteurized” or...

  19. Simulação de bloqueios periféricos guiados por ultra-som: curva de aprendizado dos residentes de anestesiologia do CET-SMA/HSL Simulacro de bloqueos periféricos guiados por ultrasonido: curva de aprendizaje de los residentes de anestesiología del CET-SMA/HSL Simulation of ultrasound-guided peripheral nerve block: learning curve of CET-SMA/HSL anesthesiology residents

    Directory of Open Access Journals (Sweden)

    Marilia Bonifácio Baranauskas

    2008-04-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A técnica de ultra-som tem sido cada vez mais utilizada para a realização de bloqueios de nervos periféricos. Existem poucos relatos na literatura que analisam a curva de aprendizado da técnica de ultra-som. O objetivo do estudo foi avaliar a curva de aprendizado dos residentes de Anestesiologia do CET-SMA/HSL em bloqueios periféricos guiados por ultra-som por meio de modelo experimental de gelatina. MÉTODO: Foi desenvolvido modelo experimental com cuba preenchida de gelatina e azeitona submersa. Nove residentes foram distribuídos aleatoriamente em três grupos (G1, G2 e G3 compostos, cada um, de um R1, um R2 e um R3. Os três grupos receberam explanação teórica. O G1 recebeu duas horas de treinamento prático, o G2 uma hora e o G3 não treinou. Na seqüência, os participantes foram solicitados a posicionar a agulha no ponto médio da parede da azeitona, próximo ao transdutor e reposicionar a agulha entre a azeitona e o fundo da cuba, simulando a injeção perineural do anestésico. Foram avaliadas a velocidade e eficácia das tarefas, além das falhas técnicas. RESULTADOS: O G1 apresentou média de tempo para realização das tarefas de 37,63 segundos, sem falhas técnicas; no G2 observou-se média de 64,40 segundos, ocorrendo duas falhas técnicas e o G3 apresentou média de 93,83 segundos, com 12 falhas técnicas. CONCLUSÕES: O estudo permite concluir que o maior tempo de treinamento em modelo experimental de bloqueios periféricos guiados por ultra-som melhorou a curva de aprendizado na simulação da técnica.JUSTIFICATIVA Y OBJETIVOS: La técnica de ultrasonido ha sido cada vez más utilizada para la realización de bloqueos de nervios periféricos. Existen pocos relatos en la literatura que analizan la curva de aprendizaje de la técnica de ultrasonido. El objetivo del estudio fue evaluar la curva de aprendizaje de los residentes de Anestesiología del CET-SMA/HSL en bloqueos periféricos guiados

  20. Investigation of Doppler spectra of laser radiation scattered inside hand skin during occlusion test

    Science.gov (United States)

    Kozlov, I. O.; Zherebtsov, E. A.; Zherebtsova, A. I.; Dremin, V. V.; Dunaev, A. V.

    2017-11-01

    Laser Doppler flowmetry (LDF) is a method widely used in diagnosis of microcirculation diseases. It is well known that information about frequency distribution of Doppler spectrum of the laser radiation scattered by moving red blood cells (RBC) usually disappears after signal processing procedure. Photocurrent’s spectrum distribution contains valuable diagnostic information about velocity distribution of the RBC. In this research it is proposed to compute the indexes of microcirculation in the sub-ranges of the Doppler spectrum as well as investigate the frequency distribution of the computed indexes.

  1. Leucemia linfoblástica aguda (LLA durante a gravidez: um relato de caso

    Directory of Open Access Journals (Sweden)

    Marcelo Gil Cliquet

    2015-10-01

    Full Text Available A incidência de Leucemia Linfoblástica Aguda (LLA associada à gestação é pequena, entretanto, devido à gravidade da doença, é fundamental que o obstetra esteja capacitado a orientar a conduta médica. O tratamento deve ser iniciado logo após o diagnóstico para que não haja prejuízo do prognóstico materno. Quando diagnosticada, sabe-se que haverá prejuízos fetais frente à quimioterapia a ser empregada. O dilema ético criado pela concomitância de neoplasias com a gestação é de difícil manejo. Objetivo: relatar o caso de uma gestante no primeiro trimestre com diagnóstico de LLA. Metodologia: as informações foram obtidas por meio de revisão do prontuário e da literatura. Relato: Relatamos o caso de uma gestante, 30 anos, com dores articulares no joelho e hemograma com pancitopenia. O mielograma e a imunofenotipagem foram compatíveis com Leucemia Linfoblástica B comum, quando a paciente estava com 12 semanas de gestação (ultrassom. A paciente foi informada sobre todos os riscos do tratamento quimioterápico para o feto, bem como os riscos maternos em postergar o tratamento. A partir da discussão entre a paciente, seus familiares e equipe médica, ela decidiu por iniciar o tratamento com protocolo BFM 86 modificado, assinando um termo de consentimento. Durante a Indução 2, foi diagnosticado óbito fetal por ultra-sonografia (21 semanas de gestação. A paciente continuou o tratamento com suporte psicológico e no momento encontra-se em remissão completa, iniciando a fase de consolidação do referido protocolo. Conclusão: Pretendemos alertar sobre a difícil decisão feita por uma paciente grávida com a LLA. Tal escolha deve ser feita com o amparo de toda a equipe médica e familiares dos pacientes, além de ser firmada por meio de um termo de consentimento.

  2. Screening for aortoiliac lesions by visual interpretation of the common femoral Doppler waveform

    DEFF Research Database (Denmark)

    Eiberg, J P; Jensen, F; Grønvall Rasmussen, J B

    2001-01-01

    to study the accuracy of simple visual interpretation of the common femoral artery Doppler waveform for screening the aorto-iliac segment for significant occlusive disease.......to study the accuracy of simple visual interpretation of the common femoral artery Doppler waveform for screening the aorto-iliac segment for significant occlusive disease....

  3. Anatomia foliar de microtomateiros fitocromo-mutantes e ultra-estrutura de cloroplastos Leaf anatomy of micro-tomato phytochrome-mutants and chloroplast ultra-structure

    Directory of Open Access Journals (Sweden)

    Hyrandir Cabral de Melo

    2011-02-01

    Full Text Available Plantas fitocromo-mutantes têm sido utilizadas com o intuito de caracterizar isoladamente, dentre os demais fotorreceptores, a ação dos fitocromos sobre eventos ligados à fotomorfogênese. Raros são os estudos que relatam a ação dos fitocromos sobre aspectos estruturais, embora sejam fundamentais à compreensão do desenvolvimento das plantas. Neste trabalho, objetivou-se analisar características ultraestruturais de cloroplastos e aspectos anatômicos foliares dos microtomateiros (Solanum lycopersicum L. cv. Micro-Tom fitocromo-mutantes aurea (subexpressa fitocromos, hp1 e atroviolacea (ambos supra-responsivos a eventos mediados por fitocromo em plantas em estágio de floração. Observou-se que os fitocromos são responsáveis pela expressão de muitas características anatômicas da epiderme foliar, assim como do mesofilo e da ultraestrutura dos cloroplastos.Phytochrome-mutant plants have been used for phytochrome action characterization among all photoreceptors, in events of photomorphogenesis. Studies relating the phytochrome action on structural aspects, which are fundamental to the comprehension of plant development, are rare. The objective of this work was to analyze chloroplast ultra structure and leaf anatomical characteristics of micro-tomatos (Solanum lycopersicum L. cv. Micro-Tom phytochrome-mutants aurea (sub express phytochrome, hp1 and atroviolacea (both super express phytochrome events-mediated in plants in the flowering stage. The results show that phytochromes are responsible for the expression of many characteristics of leaf epidermis, mesophyll and chloroplast ultra-structure.

  4. Ultra-som pulsado de baixa intensidade em fraturas diafisárias: aplicação clínica em cães Low-intensity pulsed ultrasound in diaphyseal fractures: clinical application in dogs

    Directory of Open Access Journals (Sweden)

    Valéria Lima de Sousa

    2008-08-01

    Full Text Available Os efeitos da estimulação ultra-sônica sobre a consolidação óssea têm sido demonstrados por trabalhos experimentais e clínicos. Este estudo teve por objetivo investigar a aplicação clínica do ultra-som pulsado de baixa intensidade como tratamento adjuvante de fraturas diafisárias em cães. Foram utilizados 16 cães de raças variadas, com faixa etária entre sete meses e seis anos, peso corpóreo entre 2,5 e 43kg, portadores de fraturas diafisárias fechadas recentes localizadas no rádio e ulna, fêmur ou tíbia e fíbula, estabilizadas por procedimentos de osteossíntese (fixação esquelética externa, pinos intramedulares ou a associação desses métodos. Os cães foram divididos em dois grupos: fraturas estabilizadas tratadas por ultra-som de baixa intensidade (grupo tratado, n=8; fraturas estabilizadas, não tratadas por estimulação ultra-sônica, (grupo controle, n=8. Os animais foram avaliados por exames clínicos e radiográficos nos períodos pré-operatório, pós-operatório imediato e a cada 30 dias posteriores aos procedimentos cirúrgicos. Realizou-se tratamento com ultra-som pulsado (sinal senoidal com freqüência de 1,5MHz, largura de pulso de 200µs e freqüência de repetição de 1kHz de baixa intensidade (30mW cm-2, aplicado de modo estacionário no foco de fratura. A terapia ultra-sônica foi realizada 20 minutos por dia, durante 21 dias consecutivos, a partir do período compreendido entre o 1° e o 9° dia pós-operatório. O teste t de Student, empregado na análise estatística, mostrou diferença significante (PThe effects of ultrasound stimulation on bone healing have been demonstrated in experimental and clinical studies. The purpose of this study was to investigate the clinical application of low-intensity pulsed ultrasound as an adjuvant for the treatment of diaphyseal fractures in dogs. Sixteen dogs of different breeds, ages ranging from seven months to six years, weighing from 2.5 to 43kg, were

  5. Power and color Doppler ultrasound settings for inflammatory flow: impact on scoring of disease activity in patients with rheumatoid arthritis.

    Science.gov (United States)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin; Ellegaard, Karen; D'Agostino, Maria Antonietta; Iagnocco, Annamaria; Naredo, Esperanza; Balint, Peter; Wakefield, Richard J; Torp-Pedersen, Arendse; Terslev, Lene

    2015-02-01

    To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. Six different types of ultrasound machines were used. On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity. Power Doppler was more sensitive on half of the machines, whereas color Doppler was more sensitive on the other half, using both factory settings and study settings. There was an average increase in Doppler sensitivity, despite modality, of 78% when study settings were applied. Over the 6 machines, 2 Doppler modalities, and 2 settings, the grades for each of 7 of the patients varied between 0 and 3, while the grades for each of the other 4 patients varied between 0 and 2. The effect of using different machines, Doppler modalities, and settings has a considerable influence on the quantification of inflammation by ultrasound in RA patients, and this must be taken into account in multicenter studies. Copyright © 2015 by the American College of Rheumatology.

  6. Glomerulonefritis fibrilar: Una rara forma de enfermedad glomerular por depósitos organizados

    Directory of Open Access Journals (Sweden)

    Marta B. Cabrera

    2011-10-01

    Full Text Available Se describe el caso de una mujer de 67 años de edad que consultó por debilidad y astenia, constatándose proteinuria de rango nefrótico y dislipemia. Se realizó punción para biopsia renal, la que se analizó por microscopia óptica, inmunofluorescencia y microscopia electrónica de transmisión. El análisis ultra-estructural reveló la existencia de depósitos fibrilares organizados, rectos, no ramificados, cuyo espesor osciló entre 15 y 20 nm. Dichas fibrillas ópticamente se veían como una expansión mesangial discretamente nodular, ligeramente PAS positiva, rojo Congo negativa y débilmente positiva para IgG. El diagnóstico fue glomerulonefritis fibrilar. Las enfermedades glomerulares por depósitos organizados pueden exhibir superposición sindrómica e histopatológica. Por tal motivo, resulta de importancia una primera separación entre aquellas rojo Congo positivas o negativas, siendo en este último caso la microscopia electrónica de transmisión la que diferencia dos entidades: la glomerulonefritis fibrilar y la glomerulonefritis inmunotactoide. Esta diferencia se apoya no sólo en las características ultraestructurales, sino en sus características clínicas. La glomerulonefritis inmunotactoide muestra una fuerte asociación con procesos linfoproliferativos, a diferencia de lo que ocurre con la glomerulonefritis fibrilar.

  7. Musculoskeletal colour/power Doppler in sports medicine: image parameters, artefacts, image interpretation and therapy

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, Mikael; Kønig, Merete Juhl

    2010-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  8. Musculoskeletal colour/power Doppler in sports medicine: image parameters, artefacts, image interpretation and therapy

    DEFF Research Database (Denmark)

    Boesen, M I; Boesen, Mikael; Kønig, Merete Juhl

    2011-01-01

    This review article discusses the aspects of sports medicine where musculoskeletal Doppler ultrasound has valuable contribution in diagnosis and/or treatment of some of the typical musculoskeletal sports injuries. Also, conditions where the Doppler ultrasound has no value are discussed. Some...

  9. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Newsom, R. K. [DOE ARM Climate Research Facility, Washington, DC (United States); Sivaraman, C. [DOE ARM Climate Research Facility, Washington, DC (United States); Shippert, T. R. [DOE ARM Climate Research Facility, Washington, DC (United States); Riihimaki, L. D. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    Accurate height-resolved measurements of higher-order statistical moments of vertical velocity fluctuations are crucial for improved understanding of turbulent mixing and diffusion, convective initiation, and cloud life cycles. The Atmospheric Radiation Measurement (ARM) Climate Research Facility operates coherent Doppler lidar systems at several sites around the globe. These instruments provide measurements of clear-air vertical velocity profiles in the lower troposphere with a nominal temporal resolution of 1 sec and height resolution of 30 m. The purpose of the Doppler lidar vertical velocity statistics (DLWSTATS) value-added product (VAP) is to produce height- and time-resolved estimates of vertical velocity variance, skewness, and kurtosis from these raw measurements. The VAP also produces estimates of cloud properties, including cloud-base height (CBH), cloud frequency, cloud-base vertical velocity, and cloud-base updraft fraction.

  10. Evaluation of the patients with renovascular hypertension after percutaneous revascularization by Doppler ultrasonography

    International Nuclear Information System (INIS)

    Akan, Huseyin; Arik, Nurol; Saglam, Seher; Danaci, Murat; Incesu, Lutfi; Selcuk, Mustafa Bekir

    2003-01-01

    Objective: Evaluation of the effectiveness of percutaneous revascularization is based primarily on clinical criteria, and laboratory findings rather than direct investigation of luminal width. The purpose of this study was to evaluate the success of endovascular revascularization with serial Doppler ultrasound (US) examinations. Methods and material: 19 patients (14 were atherosclerotic, five were with fibromuscular dysplasia) with suspected renovascular hypertension treated by percutaneous revascularization were included in a prospective study. Patients had 23 renal artery stenoses reducing the diameter by more than 50%. Doppler US examinations were performed before intervention, and 1 day, 3 and 6 months after intervention. Results: Initial revascularization was technically successful in 21 of 23 stenoses (91.3%) (18 PTRA, three stent placement). Hypertension was cured in five atherosclerotic and in five fibromuscular dysplasia (FMD) patients, and improved in four atherosclerotic patients. Residual stenosis was determined in six patients and the others were evaluated as normal by initial postprocedure Doppler US. As based on Doppler US, restenosis (>60%-narrowing) was depicted in four of six (66.6%) renal arteries with residual stenosis, and one of 15 (6.6%) normal renal arteries at 1 year. This difference in restenosis rates (residual stenosis vs. normal) was significant (P<0.05). Conclusion: Positive predictor for recurrence was a residual renal artery stenosis documented by Doppler US 1 day after percutaneous revascularization in atherosclerotic cases

  11. Experimental verification of the inverse Doppler effect in negative-index material

    Science.gov (United States)

    Feng, Lie; Chen, Jiabi; Wang, Yan; Geng, Tao; Zhuang, Songlin

    2010-10-01

    μResearch of negative-index material (NIM) is a very hot developing research field in recent years. NIM is also called left-handed material (LHM), in which the electric field [see manuscript], the magnetic field [see manuscript] and the wave vector [see manuscript] are not composed of a set of right-handed coordinates but a set of left-handed coordinates. Thus the action of electromagnetic waves in both left-handed material and right-handed material is just the opposite, for instance, the negative refraction phenomenon, the inverse Doppler effect and so on. Here we report the explicit result of the inverse Doppler effect through a photonic crystal (PC) prism at 10.6m wavelength for the first time, and the result we get from the experiment is much similar to the theoretical analysis we have deduced before. During the experiment, the CO2 laser is used as a light source, and the PC prism is used as a sample, which can move a tiny distance (1mm) uniformly with a translating stage. Based on the method of optical heterodyne, we let the emergent light from the output surface of PC prism and the reference light from light source interfere at the surface of the detector. When the translating stage moves towards the detector, the optical paths in the PC prism will be changed, and then the Doppler frequency shift will be generated. Though several different samples have been tested repeatedly, the results we get are extraordinarily similar. So we can be sure that the inverse Doppler effect really exists in the NIM at optical frequencies. To our best knowledge, this is the only experimental verification of the inverse Doppler effect in the NIM at optical frequencies at home and aboard.

  12. Transcranial Doppler velocimetry in aneurysmal subarachnoid haemorrhage

    DEFF Research Database (Denmark)

    Staalsø, J M; Edsen, T; Romner, B

    2013-01-01

    -coded transcranial Doppler (TCCD), with the secondary aim of describing prediction of angiographic vasospasm and mortality. METHODS: /st>Sixty patients and 70 healthy controls were each examined in duplicate by alternating operators. A total of 939 measurements divided on 201 examination sets were conducted by four...

  13. Avaliação ultra-sonográfica do segmento posterior de olhos de cães diabéticos e não diabéticos portadores de catarata Ultrasonographic evaluation of the eyes' posterior segment of diabetic and non-diabetic dogs with cataracts

    Directory of Open Access Journals (Sweden)

    Renata Squarzoni

    2007-11-01

    Full Text Available A catarata impossibilita a passagem de luz dentro do olho, dificultando o exame físico direto das estruturas oculares. É necessária a identificação prévia de quaisquer alterações oculares que contra-indiquem a cirurgia de catarata. A ultra-sonografia, ou ecografia ocular, é um exame seguro, de baixo custo, não invasivo, de fácil realização, que completa o exame oftálmico. Foi realizada avaliação ultra-sonográfica, com transdutor linear, freqüência de 10 MHz, de 225 olhos de 123 cães, sendo cães controle (Grupo 1, 52 cães não diabéticos portadores de catarata (Grupo 2 e 35 cães diabéticos portadores de catarata (Grupo 3, todos eles atendidos no Hospital Veterinário da Universidade de São Paulo. Foram encontradas as seguintes alterações ultra-sonográficas no Grupo 1: degeneração vítrea em 43%, descolamento de vítreo posterior em 7,7%, hialose asteróide em 4,6% dos olhos; no Grupo 2: degeneração vítrea em 58,9%, descolamento de vítreo posterior em 8,4%, hialose asteróide em 2,1%, processo inflamatório e/ou hemorrágico em 2,1% e descolamento de retina em 4,3% dos olhos; e no Grupo 3: degeneração vítrea em 50,7%, descolamento de vítreo posterior em 13,8%, hialose asteróide em 12,3%, processo inflamatório e/ou hemorrágico em 3,1% e descolamento de retina em 3,1% dos olhos. Concluiu-se, que (1 cães diabéticos, principalmente os que apresentam a doença há mais de 2 anos, tem maior predisposição para o desenvolvimento de hialose asteróide; (2 não houve diferença entre a freqüencia de descolamento de retina encontrada em cães diabéticos e não diabéticos; e (3 a ultra-sonografia ocular é em exame seguro, eficaz e importante na avaliação pré-operatória de cães portadores de catarata.Cataracts jeopardize the light penetration into the eye and may restrain direct exam of eye structures. It is necessary to identify very early any eye disease that could cause the failure of cataract surgery

  14. Echobiometrics kidney and renal artery triplex doppler of canine fetuses

    Directory of Open Access Journals (Sweden)

    M.A.R. Feliciano

    2014-04-01

    Full Text Available The aim of this study was to assess the sogographic parameters and biometry of canine fetal kidneys using the B mode, and to determinate the vascular index of the fetal renal arteries using the Doppler Triplex. Twenty four Shi-tzu and Pug, weighting between 4 and 10kg, aging between 4 and 6 years old were evaluated. The B mode, the fetal renal echobiometry and regularity of the renal surface, echotexture and cortex:medular ratio were evaluated during the 5th, 6th, 7th and 8th weeks of pregnancy. At the same time point of the B mode evaluation, the Doppler Triplex was carried out to assess the sistolic peak velocity (SPV, end diastolic velocity (EDV, vascular resistive (RI and pulsatility index (PI. B mode revealed no fetal renal abnormalities and echobiometry showed important measurements during fetal development (P0.05. B mode and Doppler Triplex were important tools for the assessment of fetal renal development, using echobiometry and renal arterial index in canie fetuses.

  15. Study of retrobulbar hemodynamics in diabetes via color doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2014-09-01

    Full Text Available AIM: To explore the changes of retrobulbar hemodynamics in diabetes via color doppler ultrasound. METHODS: Totally 80 patients(160 eyeswith eye diseases in type 2 diabetes from June 2010 to May 2013 in our hospital were enrolled as research group. By fundus photography and direct ophthalmoscopy, patients were assigned to diabetes without retinopathy group(DNR subgroup, non-proliferative diabetic retinopathy group(NPDR subgroupand proliferative diabetic retinopathy group(PDR subgroup. Of 60 healthy patients(120 eyesover the same period were chosen as control group. The doppler parameters of central retinal artery(CRA, posterior ciliary artery(PCAand ophthalmic artery(OAwere measured.RESULTS: There were significant differences on circulatory parameters of CRA, PCA and OA between both groups(PPPCONCLUSION: The monitoring of retinal blood flow and analysis of blood spectrum morphology via color doppler ultrasound can effectively evaluate the degree of diabetic retinopathy lesions, especially before DR vascular disease. Early detection can reveal the hemodynamic change pattern of DR, facilitating the prevention of diabetic eye complications and improvement of the quality of life.

  16. Adaptive OFDM Radar Waveform Design for Improved Micro-Doppler Estimation

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Satyabrata [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Engineering Science Advanced Research, Computer Science and Mathematics Division

    2014-07-01

    Here we analyze the performance of a wideband orthogonal frequency division multiplexing (OFDM) signal in estimating the micro-Doppler frequency of a rotating target having multiple scattering centers. The use of a frequency-diverse OFDM signal enables us to independently analyze the micro-Doppler characteristics with respect to a set of orthogonal subcarrier frequencies. We characterize the accuracy of micro-Doppler frequency estimation by computing the Cramer-Rao bound (CRB) on the angular-velocity estimate of the target. Additionally, to improve the accuracy of the estimation procedure, we formulate and solve an optimization problem by minimizing the CRB on the angular-velocity estimate with respect to the OFDM spectral coefficients. We present several numerical examples to demonstrate the CRB variations with respect to the signal-to-noise ratios, number of temporal samples, and number of OFDM subcarriers. We also analysed numerically the improvement in estimation accuracy due to the adaptive waveform design. A grid-based maximum likelihood estimation technique is applied to evaluate the corresponding mean-squared error performance.

  17. Direct measurement of Lorentz transformation with Doppler effects

    Science.gov (United States)

    Chen, Shao-Guang

    For space science and astronomy the fundamentality of one-way velocity of light (OWVL) is selfevident. The measurement of OWVL (distance/interval) and the clock synchronization with light-signal transfer make a logical circulation. This means that OWVL could not be directly measured but only come indirectly from astronomical method (Romer's Io eclipse and Bradley's sidereal aberration), furthermore, the light-year by definitional OWVL and the trigonometry distance with AU are also un-measurable. For to solve this problem two methods of clock synchronization were proposed: The direct method is that at one end of dual-speed transmissionline with single clock measure the arriving-time difference of longitudinal wave and transverse wave or ordinary light and extraordinary light, again to calculate the collective sending-time of two wave with Yang's /shear elastic-modulus ratio (E/k) or extraordinary/ordinary light refractive-index ratio (ne/no), which work as one earthquake-station with single clock measures first-shake time and the distance to epicenter; The indirect method is that the one-way wavelength l is measured by dual-counters Ca and Cb and computer's real-time operation of reading difference (Nb - Na) of two counters, the frequency f is also simultaneously measured, then l f is just OWVL. Therefore, with classical Newtonian mechanics and ether wave optics, OWVL can be measured in the Galileo coordinate system with an isotropic length unit (1889 international meter definition). Without any hypotheses special relativity can entirely establish on the metrical results. When a certain wavelength l is defined as length unit, foregoing measurement of one-way wavelength l will become as the measurement of rod's length. Let a rigidity-rod connecting Ca and Cb moves relative to lamp-house with velocity v, rod's length L = (Nb - Na) l will change follow v by known Doppler effect, i.e., L(q) =L0 (1+ (v/c) cos q), where L0 is the proper length when v= 0, v• r = v cos q

  18. The Doppler effect and the three most famous experiments for special relativity

    Directory of Open Access Journals (Sweden)

    Shukri Klinaku

    Full Text Available Using the general formula for the Doppler effect at any arbitrary angle, the three famous experiments for special theory of relativity will be examined. Explanation of the experiments of Michelson, Kennedy–Thorndike and Ives–Stilwell will be given in a precise and elegant way without postulates, arbitrary assumptions or approximations. Keywords: Doppler effect, Michelson experiment, Kennedy–Thorndike experiment, Ives–Stilwell experiment

  19. An assessment of methods of calculating Doppler effects in plutonium fuelled sodium cooled fast reactors

    International Nuclear Information System (INIS)

    Butland, A.T.D.; Reddell, G.

    1979-01-01

    After a survey of the requirements, an assessment of UK methods and data is made on the basis of the following work. First, the analysis of the SEFOR Doppler experiments, carried out using the UK FGL5 fine group nuclear data library, the MURAL cell code and whole reactor diffusion theory calculations of the neutron flux. Second, the analysis of some Japanese FCA central sample perturbation measurements of structural material Doppler effects. Third, an assessment of the accuracy of Doppler predictions in a sodium voided core using results from Zebra 5 and BIZET, and theoretical studies of additional effects relevant to power reactors and not covered by the above analyses, including the following, the calculation of Doppler effects at high temperature, fuel cycle and burn-up effects, and the heterogeneity effects of large fuelled subassemblies in pin geometry. The importance of crystalline binding effects in the fuel are discussed as is the importance of reactor material boundaries in the calculation of resonance shielding effects. Some suggestions for further Doppler studies are made. (U.K.)

  20. Three-dimensional power Doppler sonography: imaging and quantifying blood flow and vascularization.

    Science.gov (United States)

    Pairleitner, H; Steiner, H; Hasenoehrl, G; Staudach, A

    1999-08-01

    To assess the feasibility of imaging low-velocity blood flow in adnexal masses by transvaginal three-dimensional power Doppler sonography, to analyze three-dimensional power Doppler sonography data sets with a new computer-assisted method and to test the reproducibility of the technique. A commercially available 5-MHz Combison 530 ultrasound system was used to perform three-dimensional power Doppler sonography transvaginally. A cube (= volume of interest) was defined enclosing the vessels of the cyst and the Cartesian characteristics were stored on a hard disk. This cube was analyzed using specially designed software. Five indices representing vascularization (the vascularization index (VI) or blood flow (the flow index (FI)) or both (the vascularization-flow index (VFI)) were calculated. The intraobserver repeatability of cube definition and scan repetition was assessed using Hartley's test for homogeneous variances. Interobserver agreement was assessed by the Pearson correlation coefficient. Imaging of vessels with low-velocity blood flow by three-dimensional power Doppler sonography and cube definition was possible in all adnexal massed studied. In some cases even induced non-vascular flow related to endometriosis was detected. The calculated F value with intraobserver repeated Cartesian file-saving ranged from 0 to 18.8, with intraobserver scan repetition from 4.74 to 24.8 for VI, FI 1, FI 2 and VFI 1; for VFI 2 the calculated F value was 64. The interobserver correlation coefficient ranged between 0.83 and 0.92 for VI, FI 1, FI 2 and VFI 1; for VFI 2 the correlation coefficient was less than 0.75. Vessels with low-velocity blood flow can be imaged using three-dimensional power Doppler sonography. Induced non-vascular flow was detected in endometriotic cyst fluid. Three-dimensional power Doppler sonography combined with the cube method gave reproducible information for all indices except VFI 2. These indices might prove to be a new predictor in all fields of