Water Sampling and Analysis for the Tracer/Time-Lapse Radar Imaging Test at the Boise Hydrogeophysical Research Site

2002 ◽  
Author(s):  
Elisabeth Hausrath ◽  
Warren Barrash ◽  
Edward C. Reboulet
Keyword(s):  
Time Lapse ◽  
Radar Imaging ◽  
Water Sampling ◽  
Research Site ◽  
Imaging Test

Tracer/Time-Lapse Radar Imaging Test At The Boise Hydrogeophysical Research Site

2003 ◽  
Author(s):  
Warren Barrash ◽  
Michael D. Knoll ◽  
David W. Hyndman ◽  
Tom Clemo ◽  
Edward C. Reboulet ◽  
...  
Keyword(s):  
Time Lapse ◽  
Radar Imaging ◽  
Research Site ◽  
Imaging Test

Tracer/Time‐Lapse Radar Imaging Test at the Boise Hydrogeophysical Research Site

2003 ◽  
Author(s):  
Warren Barrash ◽  
Michael D. Knoll ◽  
David W. Hyndman ◽  
Tom Clemo ◽  
Edward C. Reboulet ◽  
...  
Keyword(s):  
Time Lapse ◽  
Radar Imaging ◽  
Research Site ◽  
Imaging Test

Borehole Radar Attenuation-Difference Tomography During The Tracer/Time-Lapse Test At The Boise Hydrogeophysical Research Site

2003 ◽  
Author(s):  
Sarah E. Goldstein ◽  
Tim C. Johnson ◽  
Michael D. Knoll ◽  
Warren Barrash ◽  
William P. Clement
Keyword(s):  
Time Lapse ◽  
Research Site ◽  
Borehole Radar

340-GHz 3D radar imaging test bed with 10-Hz frame rate

2012 ◽  
Author(s):  
Duncan A. Robertson ◽  
Paul N. Marsh ◽  
David R. Bolton ◽  
Robert J. C. Middleton ◽  
Robert I. Hunter ◽  
...  
Keyword(s):  
Radar Imaging ◽  
Frame Rate ◽  
Test Bed ◽  
Imaging Test

Borehole Radar Attenuation‐Difference Tomography During the Tracer/Time‐Lapse Test at the Boise Hydrogeophysical Research Site

2003 ◽  
Author(s):  
Sarah E. Goldstein ◽  
Tim C. Johnson ◽  
Michael D. Knoll ◽  
Warren Barrash ◽  
William P. Clement
Keyword(s):  
Time Lapse ◽  
Research Site ◽  
Borehole Radar

scholarly journals DETECTION OF SEEPAGE SLICKS IN CANTARELL COMPLEX (GULF OF MEXICO) USING POLARIMETRIC SAR DATA OF RADARSAT-2

2018 ◽  
Vol 36 (2) ◽  
pp. 137
Author(s):  
Sarah Barrón Torres ◽  
Luiz Bevilacqua ◽  
Fernando Pellon de Miranda ◽  
Carlos Henrique Beisl
Keyword(s):  
Gulf Of Mexico ◽  
Synthetic Aperture Radar ◽  
Incidence Angle ◽  
Alpha Angle ◽  
Time Lapse ◽  
Radar Imaging ◽  
Synthetic Aperture ◽  
Mechanism Analysis ◽  
Imaging Geometry ◽  
Aperture Radar

ABSTRACT. The occurrence of oil seeps on the sea surface from active petroleum systems has been extensively documented by radar imaging using SAR (Synthetic Aperture Radar). Polarimetry is consolidating in the oil industry as a sophisticated technique for the study of marine seeps. The Cantarell Complex, located in the Gulf of Mexico, is currently the most prolific natural seep site in the world. This paper aims to add to the discussion on the physical properties of seepage slicks from full polarimetric data (quad-pol) from RADARSAT-2 satellite. The fact that the research was based on two images (ID#02 and ID#04) acquired at the same place and with the same mode of operation but with a time lapse between acquisitions and different incidence angles allowed to evaluate the influence of the imaging geometry on target signatures. To this end, samples of four classes (sea, offshore platform, oil and false targets) were collected. The data of the samples were afterwards shown in graphs and plotted in the classification plan of Cloude & Pottier – entropy (H) vs. alpha angle (¯α) – for backscattering mechanism analysis. Such elements made it possible to certify that (i) the sea is a Bragg-type surface regardless the incidence angle, (ii) platforms have double-bounce scattering, but small incidence angles are inadequate for their characterization, (iii) false targets (associated in ID#02 to regions of little wind) are moderately random/quasi deterministic surfaces, and (iv) oil behaves either as a Bragg (19.0◦–22.7◦ incidence angle range) or as a random/anisotropic surface (33.7◦–36.7◦ incidence angle range). Keywords: H-¯α diagram, incidence angle, radar imaging, marine seeps.RESUMO. A ocorrência de exsudações de óleo na superfície do mar a partir de sistemas petrolíferos ativos vem sendo extensivamente documentada por imageamento utilizando sistemas SAR (Synthetic Aperture Radar). A polarimetria está se consolidando na indústria do petróleo como uma técnica sofisticada para o estudo de seeps marinhos. O Complexo de Cantarell, situado no Golfo do México, é atualmente o local de exsudação natural de óleo mais prolífico do globo terrestre. Este trabalho visou contribuir com a discussão acerca das propriedades físicas de escapes de óleo a partir dos dados polarimétricos completos (quad-pol) do satélite RADARSAT-2. O fato da pesquisa valer-se de duas imagens (ID#02 e ID#04) adquiridas no mesmo local e modo de operação, mas com intervalo entre as aquisições e diferentes ângulos de incidência, possibilitou avaliar a influência da geometria de imageamento na assinatura dos alvos. Com esse propósito, foram geradas amostras de quatro classes (mar, plataforma, óleo e falso alvo), que tiveram os dados posteriormente relacionados em gráficos e no plano de classificação de Cloude & Pottier – entropia (H) vs. ângulo alfa (¯α) – para análise do mecanismo de espalhamento. Tais elementos permitiram atestar que (i) o mar é uma superfície do tipo Bragg independente do ângulo de incidência, (ii) as plataformas têm espalhamento double-bounce, mas baixos ângulos são inadequados para sua caracterização, (iii) falsos alvos (associados em ID#02 a regiões de baixo vento) são superfícies moderadamente aleatórias/quase determinísticas, e (iv) o óleo comporta-se ou como Bragg (19,0◦–22,7◦), ou como uma superfície aleatória/anisotrópica (33,7◦–36,7◦).Palavras-chave: Diagrama H-¯α, ângulo de incidência, imagem de radar, seeps marinhos.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

High-voltage Electron Microscopy of astroglial cell whole mounts

1986 ◽  
Vol 44 ◽  
pp. 316-317
Author(s):  
J.N. Turner ◽  
W.G. Shain ◽  
V. Madelian ◽  
R.A. Grassucci ◽  
D.L. Forman
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Time Lapse ◽  
Astroglial Cells ◽  
High Voltage Electron Microscopy ◽  
Rat Glioma ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Nervous System Function ◽  
Beta Adrenergic Agonist

Homogeneous cultures of astroglial cells have proved useful for studying biochemical, pharmacological, and toxicological responses of astrocytes to effectors of central nervous system function. LRM 55 astroglial cells, which were derived from a rat glioma and maintained in continuous culture, exhibit a number of astrocyte properties (1-3). Stimulation of LRM 55s and astrocytes in primary cell cultures with the beta-adrenergic agonist isoproterenol results in rapid changes of morphology. Studies with time lapse video light microscopy (VLM) and high-voltage electron microscopy (HVEM) have been correlated to changes in intracellular levels of c-AMP. This report emphasizes the HVEM results.

Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

1995 ◽  
Vol 53 ◽  
pp. 972-973
Author(s):  
R H. Selinfreund ◽  
A. H. Cornell-Bell
Keyword(s):  
Membrane Potential ◽  
Confocal Microscopy ◽  
Patch Clamp ◽  
Electrical Activity ◽  
Time Lapse ◽  
Neuronal Firing ◽  
Neuronal Membrane ◽  
Pituitary Cells ◽  
Patch Clamp Recording ◽  
Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

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