1. Alinhamento Setup <ol><li> Comece por cerca de alinhar a laser, o feixe de expender, a lente ea câmera no mesmo eixo, o que seria o eixo óptico. </li><li> Ligue o laser (sem o alvo USAT), e certifique-se de que a luz passa através do centro da lente. Use uma íris de abertura para verificar. </li><li> Ligue a câmera e certifique-se de que a luz se concentra no centro da câmara. </li><li> Mudança para trás da câmera, usando o estágio linear z. Desde que o sistema está saindo do foco, o ponto de luz vai crescer. Certifique-se de que o centro da mancha permanece na mesma posição lateral. Se não, mudar cuidadosamente a posição do sistema de imagem e repita esta etapa até que o local permanece na mesma posição espacial, até um nível de pixel. </li></ol> 2. Imagem em Três planos Defocus <ol><li> Inserir o alvo do teste em frente do feixe de expender. Coloque o alvo de modo a que a luz que passa através do mesmo irá passar tháspera do centro da lente. </li><li> Capturar uma imagem. Esta imagem será um ponto de ancoragem, e sua localização será z 0, x 0 (todas as outras imagens estarão em referência à sua localização). Esta imagem será I 1, b. </li><li> Mudança para trás da câmera (usando o estágio linear z) uma distância de dz = 5,08 milímetros (ou 0,2 in) e capturar uma imagem. Esta imagem será I 2, b. </li><li> Mude de volta a câmera outra distância de dz = 5,08 milímetros (10,16 milímetros em relação ao z 0) e capturar uma imagem. Esta imagem será I 3, b. </li><li> Volte para z 0. </li></ol> 3. A varredura do Aperture <ol><li> Deslocar todo o sistema de imagem lateralmente (usando a fase linear x) uma distância de dx = 2,5 mm e captar uma imagem. Esta imagem será I 1, a. </li><li> Repita o processo no Protocolo 2. Deslocamento para trás da câmara (que utiliza a fase linear z) uma distância de dz = 5,08 milímetros, e captar uma imagem (I 2, a). Deslocar o the outra câmera distância de dz = 5,08 milímetros, e capturar uma imagem (I 3, a). </li><li> Agora, repetir o processo para o outro lado. Mudar o sistema de imagens a uma distância de dx = -2,5 mm e capturar um conjunto de três imagens em três posições z (I 1-3, c). </li><li> Volte para z 0, x 0. </li></ol> 4. Recuperação de fase (Cálculo Numérico) <ol><li> Usando o método de três aviões de 14, e imagens que eu 1-3, b, recuperar a fase óptica de imagem I 1, b. Usando a fase que foi recuperada, definir q 1, b. </li><li> Monitorizar o coeficiente de correlação entre a I 1, e b | q 1, b | 2, a fim de verificar que o processo iterativo que convergem. Para fazer isso, use a função &#39;corr2&#39; em MATLAB. </li><li> Repetir o processo de recuperação de fase I para o 1-3, um, e 1-3, c. </li></ol> 5. Imagem Super Resolvido (Cálculo Numérico) <ol><li> Ucantar Fresnel livre propagação espaço (FSP) integrante 15, de volta propagar os campos q 1, ac ao plano lente. Esses campos serão lente Ê, ac +. </li><li> Multiplique os campos resultantes lente Ê, ac + por exp (+ πix 0 2) / λf), a fim de passar de volta através da lente. Esses campos serão lente Ê, ac -. </li><li> A fim de posicionar a lente Ê campo, um na sua posição original, ele deslocar-se lateralmente uma distância de dx = 2,5 mm. </li><li> A fim de posicionar a lente Ê campo, c na sua posição original, ele deslocar-se lateralmente uma distância de dx = -2,5 mm. </li><li> Resumindo os três campos de e lente, CA, de modo a combiná-los, e sinteticamente aumentar o tamanho da abertura. </li><li> Multiplique o campo resultante por exp (-πix 0 2) / λf) e espaço livre em propagá-la ao plano de imagem. </li><li> A melhoria resolução por um fator of 3 na direção de varredura deve ser testemunhado. </li></ol>

<ol>
	<li>De Loor, G. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Possibilities+and+uses+of+radar+and+thermal+infrared+systems.">Possibilities and uses of radar and thermal infrared systems.</a> Photogrammetria. 24, 43-58 (1969).</li><li>Simonett, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Remote+sensing+with+imaging+radar:+A+review.">Remote sensing with imaging radar: A review.</a> Geoforum. , 61-74 (1970).</li><li>Born, M., Wolf, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Principles of optics: electromagnetic theory of propagation, interference and diffraction of light. , (1999).</li><li>Wiley, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+aperture+radars-a+paradigm+for+technology+evolution.">Synthetic aperture radars-a paradigm for technology evolution.</a> IEEE Trans. Aerospace Elec. Sys. 21, 440-443 (1985).</li><li>Brown, W., Porcello, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An introduction to synthetic-aperture radar. , 52-62 (1969).</li><li>Cheney, M., Borden, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fundamentals of Radar Imaging. Siam. , (2008).</li><li>Otto, R., Fritz, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Die+lehre+von+der+bildentstehung+im+mikroskop+von+Ernst+Abbe.">Die lehre von der bildentstehung im mikroskop von Ernst Abbe.</a> Vieweg Braunschweig. , (1910).</li><li>Gerchberg, W. R., Saxton, W. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+algorithm+for+the+determination+of+phase+from+image+and+diffraction+plane+pictures.">A practical algorithm for the determination of phase from image and diffraction plane pictures.</a> Optik. 35, 237-246 (1972).</li><li>Misell, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+the+solution+of+the+phase+problem+in+electron+microscopy.">A method for the solution of the phase problem in electron microscopy.</a> J. Phys. D Appl. Phys. 6, (1973).</li><li>Misell, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+examination+of+an+iterative+method+for+the+solution+of+the+phase+problem+in+optics+and+electron+optics:+I.+Test+calculations.">An examination of an iterative method for the solution of the phase problem in optics and electron optics: I. Test calculations.</a> J. Phys. D Appl. Phys. 6, 2200-2216 (1973).</li><li>Misell, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+examination+of+an+iterative+method+for+the+solution+of+the+phase+problem+in+optics+and+electron+optics.">An examination of an iterative method for the solution of the phase problem in optics and electron optics.</a> II. Sources of error. J. Phys. D Appl. Phys. 6, 2217-2225 (1973).</li><li>Fienup, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reconstruction+of+an+object+from+the+modulus+of+its+Fourier+transform.">Reconstruction of an object from the modulus of its Fourier transform.</a> Optics Lett. 3, 27-29 (1978).</li><li>Fienup, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+retrieval+algorithms:+a+comparison.">Phase retrieval algorithms: a comparison.</a> Appl. Optics. 21, 2758-2769 (1982).</li><li>Gur, E., Zalevsky, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Image+deblurring+through+static+or+time-varying+random+perturbation+medium.">Image deblurring through static or time-varying random perturbation medium.</a> J. Electron. Imaging. 18, 033016-03 (2009).</li><li>Goodman, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Introduction+to+Fourier+Optics.">Introduction to Fourier Optics.</a> Roberts &amp; Company. , (2005).</li><li>Tippie, A. E., Kumar, A., Fienup, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-resolution+synthetic-aperture+digital+holography+with+digital+phase+and+pupil+correction.">High-resolution synthetic-aperture digital holography with digital phase and pupil correction.</a> Optics Express. 19, 12027-12038 (2011).</li><li>Lim, S., Choi, K., Hahn, J., Marks, D. L., Brady, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Image-based+registration+for+synthetic+aperture+holography.">Image-based registration for synthetic aperture holography.</a> Optics Express. 19, 11716-11731 (2011).</li></ol>

Não há nada a divulgar.

A óptica radar de abertura sintética conceito (OSAR) que é apresentada neste artigo é uma nova abordagem super-resolvida que usa o algoritmo de GS e técnica de exploração, a fim de melhorar a resolução espacial de um objeto na direção da digitalização. O movimento da plataforma de imagem pode ser auto-gerado durante a utilização de uma plataforma aérea ou por satélite. Ao contrário de muitas técnicas tempo multiplexing SR, nosso método não requer qualquer informação a priori do objeto, al...

Em imagens de radar, um feixe de ângulo estreito de pulso de radiofreqüência (RF) é transmitido usando uma antena que está montada sobre uma plataforma. O sinal de radar transmite numa direcção do olhar para o lado da superfície de 1,2. O sinal reflectido é retroespalhamento a partir da superfície e é recebido pela mesma antena 2. Os sinais recebidos são convertidos para uma imagem de radar. Na real Radar de Abertura (RAR) a resolução do azimute é proporcional ao comprimento de onda e inversamente proporcional à dimensão da abertura 3. Assim, uma antena grande é necessária para a maior resolução azimutal. No entanto, é difícil atribuir grande antena a um plataformas móveis, como aviões e satélites. Em 1951, Wiley 4 sugeriram uma nova técnica de radar chamado Synthetic Aperture Radar (SAR), que utiliza o efeito Doppler criado pelo movimento da plataforma de imagem. No SAR, a amplitude, assim como a fase do sinal recebido são registados 5 </sup&gt;. Isto é possível uma vez que a frequência óptica SAR é de cerca de 1-100 6 GHz e a fase é gravado utilizando um ressonador de referência local, instalado na parte superior da plataforma. Na imagiologia óptica, os comprimentos de onda mais curtos são utilizados, tais como o visível e o infravermelho próximo (NIR), que é cerca de 1 um, isto é, frequência de cerca de 10 Hz 14. A intensidade de campo, em vez do próprio campo, está a ser detectada desde as mudanças de fase óptica muito rápidos para a detecção utilizando detectores de base de silício padrão. Enquanto imaginando um objeto através de um sistema óptico, a abertura da óptica serve como um filtro passa-baixa. Assim, a informação espacial de alta freqüência do objeto é perdido 7. Neste artigo pretende-se resolver cada uma das questões acima mencionadas separadamente, ou seja, a fase perdido eo efeito limite de difração. Gerchberg e Saxton (GS) 8 sugere que a fase óptica pode ser recupeved utilizando um processo iterativo. Misell 9-11 alargou o algoritmo para quaisquer dois planos de entrada e de saída. Essas abordagens são comprovados para convergir para uma distribuição de fase com um mínimo erro médio quadrático (MSE) 12,13. Gur e Zalevsky 14 apresentaram um método de três aviões que melhora o algoritmo Misell. Propomos e demonstrar experimentalmente que o restabelecimento da fase enquanto mudando a lente de imagem, como foi feito com a antena na aplicação SAR nos permite aumentar sinteticamente o tamanho efetivo da abertura ao longo do eixo de digitalização e, eventualmente, melhorar a resolução de imagem resultou. A aplicação de SAR em imagens ópticas usando interferometria e holografia é bem conhecida 16,17. No entanto, o método sugerido é voltado para imitar uma plataforma de imagem de varredura, tornando-o adequado para a imagem latente não-coerente (como plataforma aérea de aparência lado). Assim, o conceito de holografia, which utiliza um feixe de referência, não é adequada para tal pedido. Em vez disso, o algoritmo Gerchberg-Saxton revisto é utilizado, a fim de recuperar a fase.

<table border="0" cellpadding="0" cellspacing="0" width="1141">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Red Laser Module</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=LDM635">LDM635</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">10X Galilean Beam Expander</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=BE10M-A">BE10M-A</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Negative 1951 USAF Test Target</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=R3L3S1N">R3L3S1N</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Filter holder for 2&#34; Square Filters</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=FH2">FH2</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">1&#34; Linear Translation Stage</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=PT1">PT1</a></td>
			<td style="width:261px;">X2</td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Lens Mount for &#216;1&#34; Optics</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=LMR1">LMR1</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Lens f = 100.0mm</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=AC254-100-A">AC254-100-A</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Graduated Ring-Activated Iris Diaphragm</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://www.thorlabs.com/thorproduct.cfm?partnumber=SM1D12C">SM1D12C</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">2.5x2.5mm Aperture &#216;1&#34;</td>
			<td style="width:311px;"></td>
			<td style="width:259px;"></td>
			<td style="width:261px;">Indoor production</td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">High Resolution CMOS Camera</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=DCC1545M">DCC1545M</a></td>
			<td style="width:261px;"></td>
		</tr>
	</tbody>
</table>

time multiplexing super resolving technique for imaging from a moving platform

Propomos um método para aumentar a resolução de um objecto e ultrapassar o limite de difracção de um sistema óptico instalado no topo de um sistema de imagem em movimento, tal como uma plataforma aérea ou por satélite. O aumento da resolução é obtido num processo de dois passos. Em primeiro lugar, três imagens de baixa resolução diferente desfocados estão sendo capturados e fase óptica é recuperado usando um algoritmo iterativo baseado melhorado Gerchberg-Saxton. A recuperação de fase permite numericamente volta propagar o campo para o plano de abertura. Em segundo lugar, o sistema de formação de imagens é deslocada e o primeiro passo é repetido. Os campos ópticos obtidos no plano de abertura são combinados e um aumento sinteticamente abertura da lente é gerado ao longo da direção do movimento, produzindo resolução de imagem superior. O método assemelha-se a uma abordagem bem conhecida do regime de microondas chamado Radar de Abertura Sintética (SAR) em que o tamanho da antena é sinteticamente aumentado ao longo da plataformadireção de propagação. O método proposto é demonstrada através de experimento de laboratório.

<html> Um exemplo para os nove imagens capturadas (três imagens de desfocagem em três posições laterais) é mostrado na Figura 3. Um exemplo para a convergência GS é mostrado na Figura 4. O coeficiente de correlação para a imagem central I 1, b é superior a 0,95, e o coeficiente de correlação para as imagens laterais I 1, um, e I 1, c é acima de 0,85 (de simulação numérica completa todos eles passaram 0,99). </p...

Watch this Scientific Journal Video about Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform at JoVE.com

Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Um método para superar o limite de difração óptica é apresentado. O método inclui um processo de duas etapas: fase de recuperação óptica usando algoritmo iterativo Gerchberg-Saxton, e deslocamento do sistema de imagem seguido pela repetição da primeira etapa. A sinteticamente aumento abertura da lente é gerado ao longo da direção do movimento, produzindo resolução de imagem superior.

Técnica Tempo Multiplexing Super Resolvendo for Imaging a partir de uma plataforma móvel

We propose a method for increasing the resolution of an object and overcoming the diffraction limit of an optical system installed on top of a moving ...

time-multiplexing-super-resolving-technique-for-imaging-from-moving

Research

JoVE Journal

Engineering

8.2K visualizações.  Bar-Ilan University.  Um método para superar o limite de difração óptica é apresentado. O método inclui um processo de duas etapas: fase de recuperação óptica usando algoritmo iterativo Gerchberg-Saxton, e deslocamento do sistema de imagem seguido pela repetição da primeira etapa. A sinteticamente aumento abertura da lente é gerado ao longo da direção do movimento, produzindo resolução de imagem superior. 

Vídeo: Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Visualization of High Speed Liquid Jet Impaction on a Moving Surface

Two apparatuses for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device (for examining surface speeds between 0 and 25 m/sec) and a spinning disk device (for examining surface speeds between 15 and 100 m/sec). The air cannon linear traverse is a pneumatic energy-powered system that is designed to accelerate a metal rail surface mounted on top of a wooden projectile. A pressurized cylinder fitted with a solenoid valve rapidly releases pressurized air into the barrel, forcing the projectile down the cannon barrel. The projectile travels beneath a spray nozzle, which impinges a liquid jet onto its metal upper surface, and the projectile then hits a stopping mechanism. A camera records the jet impingement, and a pressure transducer records the spray nozzle backpressure. The spinning disk set-up consists of a steel disk that reaches speeds of 500 to 3,000 rpm via a variable frequency drive (VFD) motor. A spray system similar to that of the air cannon generates a liquid jet that impinges onto the spinning disc, and cameras placed at several optical access points record the jet impingement. Video recordings of jet impingement processes are recorded and examined to determine whether the outcome of impingement is splash, splatter, or deposition. The apparatuses are the first that involve the high speed impingement of low-Reynolds-number liquid jets on high speed moving surfaces. In addition to its rail industry applications, the described technique may be used for technical and industrial purposes such as steelmaking and may be relevant to high-speed 3D printing.

Two experimental devices for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device and a spinning disk device. The apparatuses are used to determine optimal approaches to the application of liquid friction modifier (LFM) onto rail tracks for top-of-rail friction control.

Visualização de alta velocidade líquido Jet impactação sobre uma superfície móvel

Two apparatuses for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device (for examining surface speeds ...

Engenharia

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus have potential applications in nonlinear optics, which requires extraordinary optical intensity. One of the most studied nonlinearities in plasmonics is nonlinear absorption, including saturation and reverse saturation behaviors. Although scattering and absorption in nanoparticles are closely correlated by the Mie theory, there has been no report of nonlinearities in plasmonic scattering until very recently. 
Last year, not only saturation, but also reverse saturation of scattering in an isolated plasmonic particle was demonstrated for the first time. The results showed that saturable scattering exhibits clear wavelength dependence, which seems to be directly linked to the localized surface plasmon resonance (LSPR). Combined with the intensity-dependent measurements, the results suggest the possibility of a common mechanism underlying the nonlinear behaviors of scattering and absorption. These nonlinearities of scattering from a single gold nanosphere (GNS) are widely applicable, including in super-resolution microscopy and optical switches. 
In this paper, it is described in detail how to measure nonlinearity of scattering in a single GNP and how to employ the super-resolution technique to enhance the optical imaging resolution based on saturable scattering. This discovery features the first super-resolution microscopy based on nonlinear scattering, which is a novel non-bleaching contrast method that can achieve a resolution as low as l/8 and will potentially be useful in biomedicine and material studies.

Saturable and reverse saturable scattering were discovered in isolated plasmonic particles and adopted as a novel non-bleaching contrast method in super-resolution microscopy. Here the experimental procedures of detecting and extracting nonlinear scattering are explained in detail, as well as how to enhance resolution with the aid of saturated excitation microscopy.

Medição da Dispersão Não-linearidades de um Nanoparticle plasmonic Individual

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus ...

Use of a Multi-compartment Dynamic Single Enzyme Phantom for Studies of Hyperpolarized Magnetic Resonance Agents

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due to fundamental constraints imposed by the hyperpolarized state, exotic imaging and reconstruction techniques are commonly used. A practical system for characterization of dynamic, multi-spectral imaging methods is critically needed. Such a system must reproducibly recapitulate the relevant chemical dynamics of normal and pathological tissues. The most widely utilized substrate to date is hyperpolarized [1-13C]-pyruvate for assessment of cancer metabolism. We describe an enzyme-based phantom system that mediates the conversion of pyruvate to lactate. The reaction is initiated by injection of the hyperpolarized agent into multiple chambers within the phantom, each of which contains varying concentrations of reagents that control the reaction rate. Multiple compartments are necessary to ensure that imaging sequences faithfully capture the spatial and metabolic heterogeneity of tissue. This system will aid the development and validation of advanced imaging strategies by providing chemical dynamics that are not available from conventional phantoms, as well as control and reproducibility that is not possible in vivo.

A multi-compartment dynamic phantom is used to simulate some biology of interest for metabolic studies using hyperpolarized magnet resonance agents.

O uso de um compartimento Multi-dinâmica única enzima Fantasma de Estudos de hyperpolarized agentes Ressonância Magnética

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due ...

A High Performance Impedance-based Platform for Evaporation Rate Detection

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was employed here for demonstration purposes. Multiple evaporation tests on the model compound as a humectant with various concentrations in solutions were conducted for comparison purposes. A conventional weight loss approach is known as the most straightforward, but time-consuming, measurement technique for evaporation rate detection. Yet, a clear disadvantage is that a large volume of sample is required and multiple sample tests cannot be conducted at the same time. For the first time in literature, an electrical impedance sensing chip is successfully applied to a real-time evaporation investigation in a time sharing, continuous and automatic manner. Moreover, as little as 0.5 ml of test samples is required in this impedance-based apparatus, and a large impedance variation is demonstrated among various dilute solutions. The proposed high-sensitivity and fast-response impedance sensing system is found to outperform a conventional weight loss approach in terms of evaporation rate detection.

This paper presents an impedance-based apparatus for evaporation rate detection of solutions. It offers clear advantages over a conventional weight loss approach: a fast response, high-sensitivity detection, a small sample requirement, multiple sample measurements, and easy disassembly for cleaning and reuse purposes.

A plataforma baseada em alta impedância de desempenho para a detecção Taxa de evaporação

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was ...

A Robotic Platform to Study the Foreflipper of the California Sea Lion

The California sea lion (Zalophus californianus), is an agile and powerful swimmer. Unlike many successful swimmers (dolphins, tuna), they generate most of their thrust with their large foreflippers. This protocol describes a robotic platform designed to study the hydrodynamic performance of the swimming California sea lion (Zalophus californianus). The robot is a model of the animal&#39;s foreflipper that is actuated by motors to replicate the motion of its propulsive stroke (the &#39;clap&#39;). The kinematics of the sea lion&#39;s propulsive stroke are extracted from video data of unmarked, non-research sea lions at the Smithsonian Zoological Park (SNZ). Those data form the basis of the actuation motion of the robotic flipper presented here. The geometry of the robotic flipper is based a on high-resolution laser scan of a foreflipper of an adult female sea lion, scaled to about 60% of the full-scale flipper. The articulated model has three joints, mimicking the elbow, wrist and knuckle joint of the sea lion foreflipper. The robotic platform matches dynamics properties&#8212;Reynolds number and tip speed&#8212;of the animal when accelerating from rest. The robotic flipper can be used to determine the performance (forces and torques) and resulting flowfields.

A robotic platform is described that will be used to study the hydrodynamic performance&#8212;forces and flowfields&#8212;of the swimming California sea lion. The robot is a model of the animal&#39;s foreflipper that is actuated by motors to replicate the motion of its propulsive stroke (the &#39;clap&#39;).

A plataforma robótica para estudar a Foreflipper do Leão de mar de Califórnia

The California sea lion (Zalophus californianus), is an agile and powerful swimmer. Unlike many successful swimmers (dolphins, tuna), they generate most ...

Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy (ATOM)

Scaling the number of measurable parameters, which allows for multidimensional data analysis and thus higher-confidence statistical results, has been the main trend in the advanced development of flow cytometry. Notably, adding high-resolution imaging capabilities allows for the complex morphological analysis of cellular/sub-cellular structures. This is not possible with standard flow cytometers. However, it is valuable for advancing our knowledge of cellular functions and can benefit life science research, clinical diagnostics, and environmental monitoring. Incorporating imaging capabilities into flow cytometry compromises the assay throughput, primarily due to the limitations on speed and sensitivity in the camera technologies. To overcome this speed or throughput challenge facing imaging flow cytometry while preserving the image quality, asymmetric-detection time-stretch optical microscopy (ATOM) has been demonstrated to enable high-contrast, single-cell imaging with sub-cellular resolution, at an imaging throughput as high as 100,000 cells/s. Based on the imaging concept of conventional time-stretch imaging, which relies on all-optical image encoding and retrieval through the use of ultrafast broadband laser pulses, ATOM further advances imaging performance by enhancing the image contrast of unlabeled/unstained cells. This is achieved by accessing the phase-gradient information of the cells, which is spectrally encoded into single-shot broadband pulses. Hence, ATOM is particularly advantageous in high-throughput measurements of single-cell morphology and texture &#8211; information indicative of cell types, states, and even functions. Ultimately, this could become a powerful imaging flow cytometry platform for the biophysical phenotyping of cells, complementing the current state-of-the-art biochemical-marker-based cellular assay. This work describes a protocol to establish the key modules of an ATOM system (from optical frontend to data processing and visualization backend), as well as the workflow of imaging flow cytometry based on ATOM, using human cells and micro-algae as the examples.

Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy ATOM

This protocol describes the implementation of an asymmetric-detection time-stretch optical microscopy system for single-cell imaging in ultrafast microfluidic flow and its applications in imaging flow cytometry.

Citometria de Fluxo de Imagem Microfluídica por Microscopia Óptica de Tempo-estiramento com detecção assimétrica (ATOM)

Scaling the number of measurable parameters, which allows for multidimensional data analysis and thus higher-confidence statistical results, has been the ...

Demonstration of a Hyperlens-integrated Microscope and Super-resolution Imaging

The use of super-resolution imaging to overcome the diffraction limit of conventional microscopy has attracted the interest of researchers in biology and nanotechnology. Although near-field scanning microscopy and superlenses have improved the resolution in the near-field region, far-field imaging in real-time remains a significant challenge. Recently, the hyperlens, which magnifies and converts evanescent waves into propagating waves, has emerged as a novel approach to far-field imaging. Here, we report the fabrication of a spherical hyperlens composed of alternating silver (Ag) and titanium oxide (TiO2) thin layers. Unlike a conventional cylindrical hyperlens, the spherical hyperlens allows for two-dimensional magnification. Thus, incorporation into conventional microscopy is straightforward. A new optical system integrated with the hyperlens is proposed, allowing for a sub-wavelength image to be obtained in the far-field region in real time. In this study, the fabrication and imaging setup methods are explained in detail. This work also describes the accessibility and possibility of the hyperlens, as well as practical applications of real-time imaging in living cells, which can lead to a revolution in biology and nanotechnology.

The use of a hyperlens has been regarded as a novel super-resolution imaging technique due to its advantages in real-time imaging and its simple implementation with conventional optics. Here, we present a protocol describing the fabrication and imaging applications of a spherical hyperlens.

Demonstração de um microscópio integrado Hyperlens e super resolução imagem

The use of super-resolution imaging to overcome the diffraction limit of conventional microscopy has attracted the interest of researchers in biology and ...

Multiplexing Focused Ultrasound Stimulation with Fluorescence Microscopy

By focusing low-intensity ultrasound pulses that penetrate soft tissues, LIPUS represents a promising biomedical technology to remotely and safely manipulate neural firing, hormonal secretion and genetically-reprogrammed cells. However, the translation of this technology for medical applications is currently hampered by a lack of biophysical mechanisms by which targeted tissues sense and respond to LIPUS. A suitable approach to identify these mechanisms would be to use optical biosensors in combination with LIPUS to determine underlying signaling pathways. However, implementing LIPUS to a fluorescence microscope may introduce undesired mechanical artefacts due to the presence of physical interfaces that reflect, absorb and refract acoustic waves. This article presents a step-by-step procedure to incorporate LIPUS to commercially-available upright epi-fluorescence microscopes while minimizing the influence of physical interfaces along the acoustic path. A simple procedure is described to operate a single-element ultrasound transducer and to bring the focal zone of the transducer into the objective focal point. The use of LIPUS is illustrated with an example of LIPUS-induced calcium transients in cultured human glioblastoma cells measured using calcium imaging.

Low-Intensity Pulsed Ultrasound Stimulation (LIPUS) is a modality for non-invasive mechanical stimulation of endogenous or engineered cells with high spatial and temporal resolution. This article describes how to implement LIPUS to an epi-fluorescence microscope and how to minimize acoustic impedance mismatch along the ultrasound path to prevent unwanted mechanical artefacts.

Multiplexação focada a estimulação de ultra-som com microscopia de fluorescência

By focusing low-intensity ultrasound pulses that penetrate soft tissues, LIPUS represents a promising biomedical technology to remotely and safely ...

Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method

The goal of this paper is to investigate the interaction force between droplets and super-hydrophobic substrates in the air. A measurement system based on an optical lever method is designed. A millimetric cantilever is used as a force sensitive component in the measurement system. Firstly, the force sensitivity of the optical lever is calibrated using electrostatic force, which is the critical step in measuring interaction force. Secondly, three super-hydrophobic substrates with different grid fractions are prepared with nanoparticles and copper grids. Finally, the interaction forces between droplets and super-hydrophobic substrates with different grid fractions are measured by the system. This method can be used to measure the force on the scale of sub-micronewton with a resolution on the scale of nanonewton. The in-depth study of the contact process of droplets and super-hydrophobic structures can help to improve the production efficiency in coating, film and printing. The force measurement system designed in this paper can also be used in other fields of microforce measurement.

The protocol aims to investigate the interaction between droplets and super-hydrophobic substrates in the air. This includes calibrating the measurement system and measuring the interaction force at super-hydrophobic substrates with different grid fractions.

Medindo a força de interação entre um droplet e um substrato super-hidrofóbico pelo método de alavanca óptica

The goal of this paper is to investigate the interaction force between droplets and super-hydrophobic substrates in the air. A measurement system based on ...

Design, Instrumentation and Usage Protocols for Distributed In Situ Thermal Hot Spots Monitoring in Electric Coils using FBG Sensor Multiplexing

Random wound coils are a key operational element of most electric apparatus in modern industrial systems, including low voltage electric machines. One of the major current bottlenecks in improved exploitation of electrical devices is the high sensitivity of their wound components to in-service thermal stress. The application of conventional thermal sensing methods (e.g., thermocouples, resistance temperature detectors) for thermal condition monitoring of current carrying random wound coils can impose considerable operational limitations due to sensor size, EMI sensitivity and the existence of electrically conductive material in their construction. Another substantial limitation exists in distributed sensing applications and is caused by what is often a considerable length and volume of conventional sensor wiring leads.
This paper reports the design of a fiber optic FBG&#160;sensing system&#160;intended for enabling real-time distributed internal thermal&#160;condition monitoring within random wound coils. The procedure of random wound coil instrumentation with the FBG sensing system is reported in a case study on an IEEE standard wound coil representative of those utilized in electrical machines. The reported work also presents and discusses important practical and technical aspects of FBG sensing system implementation and application, including the FBG array geometry design, sensing head and fiber packaging, the sensor array installation and calibration procedure and the use of a commercial interrogation system for obtaining thermal measurements. Finally, the in situ multiplexed FBG sensing system thermal monitoring performance is demonstrated in representative static and dynamic thermal conditions.&#160;

This paper presents a protocol that enables instrumentation of random wound electric coils with fiber Bragg grating (FBG) thermal sensors for the purpose of distributed condition monitoring of internal thermal hot spots.

Protocolos de design, instrumentação e uso para monitoramento de pontos quentes em ondas térmicas distribuídas em bobinas elétricas usando multiplexação de sensores FBG

Random wound coils are a key operational element of most electric apparatus in modern industrial systems, including low voltage electric machines. One of ...