Base de dados : MEDLINE
Pesquisa : L01.178.847.500 [Categoria DeCS]
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[PMID]:29023544
[Au] Autor:Oziel M; Korenstein R; Rubinsky B
[Ad] Endereço:Department of Physiology and Pharmacology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
[Ti] Título:Radar based technology for non-contact monitoring of accumulation of blood in the head: A numerical study.
[So] Source:PLoS One;12(10):e0186381, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: This theoretical study examines the use of radar to continuously monitor "accumulation of blood in the head" (ACBH) non-invasively and from a distance, after the location of a hematoma or hemorrhage in the brain was initially identified with conventional medical imaging. Current clinical practice is to monitor ABCH with multiple, subsequent, conventional medical imaging. The radar technology introduced in this study could provide a lower cost and safe alternative to multiple conventional medical imaging monitoring for ACBH. MATERIALS AND METHODS: The goal of this study is to evaluate the feasibility of using radar to monitor changes in blood volume in the brain through a numerical simulation of ACBH monitoring from remote, with a directional spiral slot antennae, in 3-D models of the brain. The focus of this study is on evaluating the effect of frequencies on the antennae reading. To that end we performed the calculations for frequencies of 100 MHz, 500 MHz and 1 GHz. RESULTS AND DISCUSSION: The analysis shows that the ACBH can be monitored with radar and the monitoring resolution improves with an increase in frequency, in the range studied. However, it also appears that when typical clinical dimensions of hematoma and hemorrhage are used, the variable ratio of blood volume radius and radar wavelength can bring the measurements into the Mie and Rayleigh regions of the radar cross section. In these regions there is an oscillatory change in signal with blood volume size. For some frequencies there is an increase in signal with an increase in volume while in others there is a decrease. CONCLUSIONS: While radar can be used to monitor ACBH non-invasively and from a distance, the observed Mie region dependent oscillatory relation between blood volume size and wavelength requires further investigation. Classifiers, multifrequency algorithms or ultra-wide band radar are possible solutions that should be explored in the future.
[Mh] Termos MeSH primário: Encéfalo/fisiologia
Modelos Teóricos
Monitorização Fisiológica/métodos
[Mh] Termos MeSH secundário: Adulto
Encéfalo/anatomia & histologia
Encéfalo/diagnóstico por imagem
Mapeamento Encefálico
Seres Humanos
Imagem por Ressonância Magnética
Masculino
Radar
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171013
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186381


  2 / 895 MEDLINE  
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[PMID]:28961264
[Au] Autor:de Michele M; Ergintav S; Aochi H; Raucoules D
[Ad] Endereço:Natural Risks department, French Geological Survey (BRGM), Orléans, France.
[Ti] Título:An L-band interferometric synthetic aperture radar study on the Ganos section of the north Anatolian fault zone between 2007 and 2011: Evidence for along strike segmentation and creep in a shallow fault patch.
[So] Source:PLoS One;12(9):e0185422, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We utilize L-band interferometric synthetic aperture radar (InSAR) data in this study to retrieve a ground velocity map for the near field of the Ganos section of the north Anatolian fault (NAF) zone. The segmentation and creep distribution of this section, which last ruptured in 1912 to generate a moment magnitude (Mw)7.3 earthquake, remains incompletely understood. Because InSAR processing removes the mean orbital plane, we do not investigate large scale displacements due to regional tectonics in this study as these can be determined using global positioning system (GPS) data, instead concentrating on the close-to-the-fault displacement field. Our aim is to determine whether, or not, it is possible to retrieve robust near field velocity maps from stacking L-band interferograms, combining both single and dual polarization SAR data. In addition, we discuss whether a crustal velocity map can be used to complement GPS observations in an attempt to discriminate the present-day surface displacement of the Ganos fault (GF) across multiple segments. Finally, we characterize the spatial distribution of creep on shallow patches along multiple along-strike segments at shallow depths. Our results suggest the presence of fault segmentation along strike as well as creep on the shallow part of the fault (i.e. the existence of a shallow creeping patch) or the presence of a smoother section on the fault plane. Data imply a heterogeneous fault plane with more complex mechanics than previously thought. Because this study improves our knowledge of the mechanisms underlying the GF, our results have implications for local seismic hazard assessment.
[Mh] Termos MeSH primário: Terremotos
Interferometria/métodos
Radar
[Mh] Termos MeSH secundário: Turquia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170930
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185422


  3 / 895 MEDLINE  
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[PMID]:28541338
[Au] Autor:Popkin G
[Ti] Título:Earth-observing companies push for more-advanced science satellites.
[So] Source:Nature;545(7655):397, 2017 05 23.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Mh] Termos MeSH primário: Terra (Planeta)
Ciências da Terra/economia
Ciências da Terra/instrumentação
Setor Privado/economia
Imagens de Satélites/economia
Imagens de Satélites/instrumentação
[Mh] Termos MeSH secundário: Agricultura/economia
Radar/instrumentação
Pesquisa/economia
Pesquisa/instrumentação
Estados Unidos
United States National Aeronautics and Space Administration/economia
Tempo (Meteorologia)
[Pt] Tipo de publicação:NEWS
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170914
[Lr] Data última revisão:
170914
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1038/545397a


  4 / 895 MEDLINE  
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[PMID]:28417836
[Au] Autor:Shin YH; Yun C; Han AH
[Ti] Título:Cervical Spine Status of Pilots and Air-Controllers of Airborne Early Warning and Control Aircraft.
[So] Source:Aerosp Med Hum Perform;88(5):476-480, 2017 May 01.
[Is] ISSN:2375-6314
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: Many countries have developed their own airborne early warning and control (AEW&C) systems for use in surveying their territorial sky in real time. However, a review of the literature suggests that no studies have been conducted to analyze the cervical spine of pilots and air-controllers of AEW&C aircraft. METHODS: The study subjects were 80 pilots and air-controllers of AEW&C aircraft with a period of service of > 1 yr and had data on physical examinations, simple radiographs and functional scores of the axial skeleton, and questionnaires about lifestyle and working conditions. Information about physical characteristics and experience of neck pain were collected. Functional scores including the neck disability index and short-form 36-item health survey were obtained. Radiological measurements were performed for the C2-7 Cobb angle and degree of forward head posture. RESULTS: Of the 80 subjects, 33 (41.3%) had experienced neck pain and 63 (78.8%) had impaired cervical lordosis. The results of functional and radiological evaluations were not significantly different between pilots and air-controllers. In multivariate analysis, only the age was significantly related to the occurrence of impaired cervical lordosis. However, there were no significant factors related to the occurrence of neck pain. DISCUSSION: The results of this study suggest that the working environment of pilots and air-controllers of AEW&C aircraft has a negative effect on their cervical spine. Age seemed to be the most significant factor affecting the occurrence of impaired cervical lordosis in these subjects.Shin YH, Yun C, Han AH. Cervical spine status of pilots and air-controllers of airborne early warning and control aircraft. Aerosp Med Hum Perform. 2017; 88(5):476-480.
[Mh] Termos MeSH primário: Medicina Aeroespacial
Aviação
Vértebras Cervicais/diagnóstico por imagem
Cervicalgia/epidemiologia
Exposição Ocupacional
Pilotos
Postura
[Mh] Termos MeSH secundário: Adulto
Fatores Etários
Feminino
Seres Humanos
Masculino
Análise Multivariada
Cervicalgia/diagnóstico por imagem
Radar
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170615
[Lr] Data última revisão:
170615
[Sb] Subgrupo de revista:IM; S
[Da] Data de entrada para processamento:170419
[St] Status:MEDLINE
[do] DOI:10.3357/AMHP.4734.2017


  5 / 895 MEDLINE  
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[PMID]:28409576
[Au] Autor:Matyjasiak P
[Ad] Endereço:Department of Evolutionary Biology, Faculty of Biology and Environmental Sciences, Cardinal Stefan Wyszynski University in Warsaw, 1/3 Wóycickiego St., PL-01-938 Warsaw, Poland.
[Ti] Título:[Radar as imaging tool in ecology and conservation biology].
[Ti] Título:Radar jako narzedzie obrazowania w ekologii i ochronie przyrody..
[So] Source:Postepy Biochem;63(1):59-67, 2017.
[Is] ISSN:0032-5422
[Cp] País de publicação:Poland
[La] Idioma:pol
[Ab] Resumo:Migrations and dispersal are among the most important ecological processes that shape ecosystems and influence our economy, health and safety. Movements of birds, bats and insects occur in a large spatial scale - regional, continental, or intercontinental. However, studies of these phenomena using classic methods are usually local. Breakthrough came with the development of radar technology, which enabled researchers to study animal movements in the atmosphere in a large spatial and temporal scale. The aim of this article was to present the radar imaging methods used in the research of aerial movements of birds, bats and insects. The types of radars used in research are described, and examples of the use of radar in basic research and in conservation biology are discussed. Radar visualizations are used in studies on the effect of meteorological conditions on bird migration, on spatial and temporal dynamics of movements of birds, bats and insects, and on the mechanism of orientation of migrating birds and insects. In conservation biology research radars are used in the monitoring of endangered species of birds and bats, to monitor bird activity at airports, as well as in assessing the impact of high constructions on flying birds and bats.
[Mh] Termos MeSH primário: Conservação dos Recursos Naturais/métodos
Ecologia/métodos
Radar
[Mh] Termos MeSH secundário: Animais
Aves
Quirópteros
Voo Animal
Insetos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170415
[St] Status:MEDLINE


  6 / 895 MEDLINE  
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[PMID]:28394932
[Au] Autor:Pieraccini M; Betti M; Forcellini D; Dei D; Papi F; Bartoli G; Facchini L; Corazzi R; Kovacevic VC
[Ad] Endereço:Department of Information Engineering (DINFO), University of Florence, Florence, Italy.
[Ti] Título:Radar detection of pedestrian-induced vibrations on Michelangelo's David.
[So] Source:PLoS One;12(4):e0174480, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This paper summarizes the results of a two-day dynamic monitoring of Michelangelo's David subject to environmental loads (city traffic and pedestrian loading induced by tourists visiting the Accademia Gallery). The monitoring was carried out by a no-contact technique using an interferometric radar, whose effectiveness in measuring the resonant frequencies of structures and historic monuments has proved over the last years through numerous monitoring activities. Owing to the dynamic behavior of the measurement system (radar and tripod), an accelerometer has been installed on the radar head to filter out the movement component of the measuring instrument from the measurement of the David's displacement. Measurements were carried out in the presence and absence of visitors, to assess their influence on the dynamic behavior of the statue. A numerical model of the statue was employed to evaluate the experimental results.
[Mh] Termos MeSH primário: Pedestres
Escultura
Vibração
[Mh] Termos MeSH secundário: Acelerometria
Meio Ambiente
Seres Humanos
Interferometria
Modelos Teóricos
Museus
Radar
Transportes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170830
[Lr] Data última revisão:
170830
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170411
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0174480


  7 / 895 MEDLINE  
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[PMID]:28091883
[Au] Autor:Wijewardana YN; Shilpadi AT; Mowjood MI; Kawamoto K; Galagedara LW
[Ad] Endereço:Uva Wellassa University, Badulla, Sri Lanka.
[Ti] Título:Ground-penetrating radar (GPR) responses for sub-surface salt contamination and solid waste: modeling and controlled lysimeter studies.
[So] Source:Environ Monit Assess;189(2):57, 2017 Feb.
[Is] ISSN:1573-2959
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The assessment of polluted areas and municipal solid waste (MSW) sites using non-destructive geophysical methods is timely and much needed in the field of environmental monitoring and management. The objectives of this study are (i) to evaluate the ground-penetrating radar (GPR) wave responses as a result of different electrical conductivity (EC) in groundwater and (ii) to conduct MSW stratification using a controlled lysimeter and modeling approach. A GPR wave simulation was carried out using GprMax2D software, and the field test was done on two lysimeters that were filled with sand (Lysimeter-1) and MSW (Lysimeter-2). A Pulse EKKO-Pro GPR system with 200- and 500-MHz center frequency antennae was used to collect GPR field data. Amplitudes of GPR-reflected waves (sub-surface reflectors and water table) were studied under different EC levels injected to the water table. Modeling results revealed that the signal strength of the reflected wave decreases with increasing EC levels and the disappearance of the subsurface reflection and wave amplitude reaching zero at higher EC levels (when EC >0.28 S/m). Further, when the EC level was high, the plume thickness did not have a significant effect on the amplitude of the reflected wave. However, it was also found that reflected signal strength decreases with increasing plume thickness at a given EC level. 2D GPR profile images under wet conditions showed stratification of the waste layers and relative thickness, but it was difficult to resolve the waste layers under dry conditions. These results show that the GPR as a non-destructive method with a relatively larger sample volume can be used to identify highly polluted areas with inorganic contaminants in groundwater and waste stratification. The current methods of MSW dumpsite investigation are tedious, destructive, time consuming, costly, and provide only point-scale measurements. However, further research is needed to verify the results under heterogeneous aquifer conditions and complex dumpsite conditions.
[Mh] Termos MeSH primário: Monitoramento Ambiental/métodos
Água Subterrânea/química
Radar
Cloreto de Sódio/análise
Resíduos Sólidos
[Mh] Termos MeSH secundário: Condutividade Elétrica
Monitoramento Ambiental/instrumentação
Eliminação de Resíduos/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Solid Waste); 451W47IQ8X (Sodium Chloride)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171020
[Lr] Data última revisão:
171020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170117
[St] Status:MEDLINE
[do] DOI:10.1007/s10661-017-5770-4


  8 / 895 MEDLINE  
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[PMID]:27337707
[Au] Autor:Buxi D; Redout JM; Yuce MR
[Ti] Título:Blood Pressure Estimation Using Pulse Transit Time From Bioimpedance and Continuous Wave Radar.
[So] Source:IEEE Trans Biomed Eng;64(4):917-927, 2017 Apr.
[Is] ISSN:1558-2531
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: We have developed and tested a new architecture for pulse transit time (PTT) estimation at the central arteries using electrical bioimpedance, electrocardiogram, and continuous wave radar to estimate cuffless blood pressure. METHODS: A transmitter and receiver antenna are placed at the sternum to acquire the arterial pulsation at the aortic arch. A four-electrode arrangement across the shoulders acquires arterial pulse across the carotid and subclavian arteries from bioimpedance as well as a bipolar lead I electrocardiogram. The PTT and pulse arrival times (PATs) are measured on six healthy male subjects during exercise on a bicycle ergometer. Using linear regression, the estimated PAT and PTT values are calibrated to the systolic and mean as well as diastolic blood pressure from an oscillometric device. RESULTS: For all subjects, the Pearson correlation coefficients for PAT-SBP and PTT-SBP are -0.66 (p = 0.001) and -0.48 (p = 0.0029), respectively. Correlation coefficients for individual subjects ranged from -0.54 to -0.9 and -0.37 to -0.95, respectively. CONCLUSION: The proposed system architecture is promising in estimating cuffless arterial blood pressure at the central, proximal arteries, which obey the Moens-Korteweg equation more closely when compared to peripheral arteries. SIGNIFICANCE: An important advantage of PTT from the carotid and subclavian arteries is that the PTT over the central elastic arteries is measured instead of the peripheral arteries, which potentially reduces the changes in PTT due to vasomotion. Furthermore, the sensors can be completely hidden under a patients clothes, making them more acceptable by the patient for ambulatory monitoring.
[Mh] Termos MeSH primário: Determinação da Pressão Arterial/instrumentação
Pressão Sanguínea/fisiologia
Cardiografia de Impedância/instrumentação
Diagnóstico por Computador/métodos
Análise de Onda de Pulso/métodos
Radar
[Mh] Termos MeSH secundário: Algoritmos
Determinação da Pressão Arterial/métodos
Cardiografia de Impedância/métodos
Diagnóstico por Computador/instrumentação
Eletrodos
Desenho de Equipamento
Análise de Falha de Equipamento
Seres Humanos
Masculino
Micro-Ondas
Reprodutibilidade dos Testes
Sensibilidade e Especificidade
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160624
[St] Status:MEDLINE
[do] DOI:10.1109/TBME.2016.2582472


  9 / 895 MEDLINE  
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[PMID]:26955012
[Au] Autor:Byrne D; Sarafianou M; Craddock IJ
[Ti] Título:Compound Radar Approach for Breast Imaging.
[So] Source:IEEE Trans Biomed Eng;64(1):40-51, 2017 Jan.
[Is] ISSN:1558-2531
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Multistatic radar apertures record scattering at a number of receivers when the target is illuminated by a single transmitter, providing more scattering information than its monostatic counterpart per transmission angle. This paper considers the well-known problem of detecting tumor targets within breast phantoms using multistatic radar. To accurately image potentially cancerous targets size within the breast, a significant number of multistatic channels are required in order to adequately calibrate-out unwanted skin reflections, increase the immunity to clutter, and increase the dynamic range of a breast radar imaging system. However, increasing the density of antennas within a physical array is inevitably limited by the geometry of the antenna elements designed to operate with biological tissues at microwave frequencies. A novel compound imaging approach is presented to overcome these physical constraints and improve the imaging capabilities of a multistatic radar imaging modality for breast scanning applications. The number of transmit-receive (TX-RX) paths available for imaging are increased by performing a number of breast scans with varying array positions. A skin calibration method is presented to reduce the influence of skin reflections from each channel. Calibrated signals are applied to receive a beamforming method, compounding the data from each scan to produce a microwave radar breast profile. The proposed imaging method is evaluated with experimental data obtained from constructed phantoms of varying complexity, skin contour asymmetries, and challenging tumor positions and sizes. For each imaging scenario outlined in this study, the proposed compound imaging technique improves skin calibration, clearly detects small targets, and substantially reduces the level of undesirable clutter within the profile.
[Mh] Termos MeSH primário: Algoritmos
Neoplasias da Mama/diagnóstico por imagem
Aumento da Imagem/métodos
Interpretação de Imagem Assistida por Computador/métodos
Micro-Ondas
Radar/instrumentação
[Mh] Termos MeSH secundário: Seres Humanos
Imagens de Fantasmas
Reprodutibilidade dos Testes
Sensibilidade e Especificidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160309
[St] Status:MEDLINE
[do] DOI:10.1109/TBME.2016.2536703


  10 / 895 MEDLINE  
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[PMID]:28269085
[Au] Autor:Van Nguyen; Javaid AQ; Weitnauer MA
[Ti] Título:Detection of motion and posture change using an IR-UWB radar.
[So] Source:Conf Proc IEEE Eng Med Biol Soc;2016:3650-3653, 2016 08.
[Is] ISSN:1557-170X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Impulse radio ultra-wide band (IR-UWB) radar has recently emerged as a promising candidate for non-contact monitoring of respiration and heart rate. Different studies have reported various radar based algorithms for estimation of these physiological parameters. The radar can be placed under a subject's mattress as he lays stationary on his back or it can be attached to the ceiling directly above the subject's bed. However, advertent or inadvertent movement on part of the subject and different postures can affect the radar returned signal and also the accuracy of the estimated parameters from it. The detection and analysis of these postural changes can not only lead to improvement in estimation algorithms but also towards prevention of bed sores and ulcers in patients who require periodic posture changes. In this paper, we present an algorithm that detects and quantifies different types of motion events using an under-the-mattress IR-UWB radar. The algorithm also indicates a change in posture after a macro-movement event. Based on the findings of this paper, we anticipate that IR-UWB radar can be used for extracting posture related information in non-clinical enviroments for patients who are bed-ridden.
[Mh] Termos MeSH primário: Algoritmos
Monitorização Fisiológica/métodos
Postura/fisiologia
Radar
[Mh] Termos MeSH secundário: Adulto
Feminino
Frequência Cardíaca/fisiologia
Seres Humanos
Masculino
Meia-Idade
Monitorização Fisiológica/instrumentação
Movimento
Radar/instrumentação
Respiração
Processamento de Sinais Assistido por Computador
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171122
[Lr] Data última revisão:
171122
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170309
[St] Status:MEDLINE
[do] DOI:10.1109/EMBC.2016.7591519



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