Optical Patch Research Articles

The association between habitual alcohol intake and electrical conduction disturbances: mechanistic insights into the electrical disturbances after long-term ethanol ingestion

Background: Alcohol-induced cardiac remodeling has been well documented. However, data regarding the dose-related ventricular electrical disturbances and the exact pathophysiologic mechanisms remained largely unknown. Methods: We examined in a community-dwelling cohort the cardiac electromechanical dysfunction among 260 participants (mean age: 64.9 years, 57.5% female) who had habitual alcohol consumption. In parallel, adult male C57BL/6 mice were fed a liquid diet containing 4% or 6% alcohol, or a normal diet (Ctrl) for 14 weeks followed by electrophysiological (whole heart optical mapping and single cardiomyocyte patch clamp technique) examination and analysis of sodium channel (INaV 1.5), gap junctions, and fibrosis. Results: When categorized by daily alcohol consumption (heavy group: >90 gm/day), the heavy alcohol consumption group demonstrated larger mass (trend p 30% decrement, both p<0.05). Expression of type 1 collagen markedly increased in the 6% alcohol groups. ![Figure][1] Figure 1 Conclusion: Chronic alcohol ingestion in humans manifested dose-related cardiac electrical disturbances and unfavorable LV geometry, which were highly mimicked by the mice model. The slower ventricular conduction in mice fed alcohol is attributed to the suppressed sodium channels and gap junctions, as well as an increase of fibrosis. [1]: pending:yes

Optical microstrip patch antennas design and analysis

This paper has presented transparent conductor oxide materials (TCOMs) based microstrip patch antennas with glass substrate and copper ground plane, which have been deeply analyzed in the visible spectrum region in comparison with the practical patch antenna model of indium tin oxide patch with glass substrate and different TCOMs based ground plane. As well as the study have investigated the effect of transparent oxide materials on patch antenna design instead of perfect conductor materials such as copper that has low cost and weight. The tradeoff between optical transparency and electrical conductivity will be evaluated for a range of visible regions. Microstrip transmission line feed method is used to predict the skin effects on a patch antenna and their impact on antenna efficiency, resonance frequency and optical transmission are also described. This study have discussed assessment of these tradeoffs and effect of TCOMs parameters on antenna design.

Controlling Spontaneous Emission with Plasmonic Optical Patch Antennas

We experimentally demonstrate the control of the spontaneous emission rate and the radiation pattern of colloidal quantum dots deterministically positioned in a plasmonic patch antenna. The antenna consists of a thin gold microdisk separated from a planar gold layer by a few tens of nanometers thick dielectric layer. The emitters are shown to radiate through the entire patch antenna in a highly directional and vertical radiation pattern. Strong acceleration of spontaneous emission is observed, depending on the antenna geometry. Considering the double dipole structure of the emitters, this corresponds to a Purcell factor up to 80 for dipoles perpendicular to the disk.

Impact of nonlocal response on metallodielectric multilayers and optical patch antennas

We analyze the impact of nonlocality on the waveguide modes of metallo-dielectric multilayers and optical patch antennas, the latter formed from metal strips closely spaced above a metallic plane. We model both the nonlocal effects associated with the conduction electrons of the metal, as well as the previously overlooked response of bound electrons. We show that the fundamental mode of a metal-dielectric-metal waveguide, sometimes called the gap-plasmon, is very sensitive to nonlocality when the insulating, dielectric layers are thinner than 5 nm. We suggest that optical patch antennas, which can easily be fabricated with controlled dielectric spacer layers and can be interrogated using far-field scattering, can enable the measurement of nonlocality in metals with good accuracy.

광섬유 피드 리트로마운트형 분광계

A low-dispersion fiber feed Littrow-mounted grating spectrometer for education was designed and fabricated. The dispersion element is a reflective type blazed grating Edmundoptics NT 46-075 (spatial frequency 600 lines/mm, dimension <TEX>$30mm{\times}30mm$</TEX>, blazed angle 8.6 degree). The optical fiber coupler module for optical guiding from telescope to spectrometer is composed of a multi-mode FC connector - FC connector optical fiber patch cord (core/cladding diameter <TEX>$50{\mu}m/125{\mu}m$</TEX>) and two 1.25" throw-tube couplers. The lens for collimating and imaging is a general purpose focal length 50 mm camera lens (f/1.8). The device for optical path control is a rectangular prism (size <TEX>$25mm{\times}25mm$</TEX>). The imaging camera sensor is a Meade DSI Pro 2 CCD sensor (black and white, <TEX>$752{\times}582$</TEX> pixels and pixel size <TEX>$8.3{\mu}m{\times}8.6{\mu}m$</TEX>). Softwares for data logging and analysis consist of Meade Autostar Suite, NIH imagej and Vernier Logger Pro 3. The wavelength coverage range of the spectrometer is 205 nm at central wavelength 550 nm. The wavelength resolution is 1.7 nm.

Waveguide-fed optical hybrid plasmonic patch nano-antenna

We propose a novel optical hybrid plasmonic patch nano-antenna for operation at the standard telecommunication wavelength of 1550 nm. The nano-antenna is designed to be compatible with a hybrid plasmonic waveguide through matching of both the operational mode and the wave impedance. The antenna is designed to receive the optical signal from a planar waveguide and redirect the signal out of plane, and is therefore useful for inter- or intra-chip optical communications and sensing. The transmission line model in conjunction with surface plasmon theory is used to develop analytical formulas for design and analysis, and a 3-dimensional full-wave numerical method is used to validate the design. The proposed device provides a bandwidth of more than 15 THz, a gain of 5.6 dB, and an efficiency of 87%. Furthermore, by designing an 8 × 8 array of the proposed antenna, a directivity of 20 dBi and steering of the beam angle are achieved by controlling the relative phase shift between elements of the array.

Polarization conversion with elliptical patch nanoantennas

In this paper, we demonstrate arrays of optical patch nanoantennas can convert light polarization through reflection. By breaking the azimuthal symmetry, elliptical plasmonic patch nanoantennas exhibit both even and odd cavity modes, which can be expressed by Mathieu functions. It is shown that by properly orienting the incident polarization, a linearly polarized light in resonance with one cavity mode can be converted into an elliptical or circular polarization after reflection. Since the major cavity modes can be excited at all incident angles, the polarization conversion by these elliptical patch nanoantennas can be realized with wide range of incident angles.

ELECTRO-OPTIC MICROWAVE-LIGHTWAVE CONVERTERS UTILIZING PATCH ANTENNAS WITH ORTHOGONAL GAPS

We propose a new electro-optic microwave-lightwave converter using two orthogonal optical waveguides and patch antennas embedded with two orthogonal gaps. Wireless microwave signals can be received, separated and converted directly to lightwave signals through optical modulation using the proposed device. This device operates with no external power supply and with low microwave distortion. In addition, it enables us to measure the magnitude, phase and polarization of the wireless signal simultaneously. Experimental demonstrations of the device were presented at the operation frequency of 26 GHz. The device can be applied for electromagnetic compatibility test in the radio-over-fiber link.

Ophthalmic features of CHARGE syndrome with CHD7 mutations

Coloboma and various ocular abnormalities have been described in CHARGE syndrome, although the severity of visual impairment varies from case to case. We conducted a multicenter study to clarify the ophthalmic features of patients with molecularly confirmed CHARGE syndrome. Thirty-eight eyes in 19 patients with CHARGE syndrome and confirmed CHD7 mutations treated at four centers were retrospectively studied. Colobomata affected the posterior segment of 35 eyes in 18 patients. Both retinochoroidal and optic disk colobomata were bilaterally observed in 15 patients and unilaterally observed in 3 patients. The coloboma involved the macula totally or partially in 21 eyes of 13 patients. We confirmed that bilateral large retinochoroidal colobomata represents a typical ophthalmic feature of CHARGE syndrome in patients with confirmed CHD7 mutations; however, even eyes with large colobomata can form maculas. The anatomical severity of the eye defect was graded according to the presence of colobomata, macula defect, and microphthalmos. A comparison of the severity in one eye with that in the other eye revealed a low-to-moderate degree of agreement between the two eyes, reflecting the general facial asymmetry of patients with CHARGE syndrome. The location of protein truncation and the anatomical severity of the eyes were significantly correlated. We suggested that the early diagnosis of retinal morphology and function may be beneficial to patients, since such attention may determine whether treatment for amblyopia, such as optical correction and patching, will be effective in facilitating the visual potential or whether care for poor vision will be needed.

Use of Channelrhodopsin for Activation of CNS Neurons

Optogenetics-the use of optically activated proteins to control cell function-allows for control of neurons with an unprecedented degree of spatial, temporal, and neurochemical precision. Three protocols are presented in this unit describing the use of channelrhodopsin-2 (ChR2), a light-activated cation channel. These protocols emphasize practical issues of working with ChR2, including guidelines for selecting a gene delivery method, light source, and method of tissue implantation, as well as steps for fabricating fiber optic patch cables and chronic implantable optical fibers. The first protocol describes the use of ChR2 in electrophysiological recordings from brain slices. The second and third involve the use of ChR2 in vivo, with light delivered through chronic fiber implants or guide cannula.

Real Time 3D Visualization of Intraoperative Organ Deformations Using Structured Dictionary

Restricted visualization of the surgical field is one of the most critical challenges for minimally invasive surgery (MIS). Current intraoperative visualization systems are promising. However, they can hardly meet the requirements of high resolution and real time 3D visualization of the surgical scene to support the recognition of anatomic structures for safe MIS procedures. In this paper, we present a new approach for real time 3D visualization of organ deformations based on optical imaging patches with limited field-of-view and a single preoperative scan of magnetic resonance imaging (MRI) or computed tomography (CT). The idea for reconstruction is motivated by our empirical observation that the spherical harmonic coefficients corresponding to distorted surfaces of a given organ lie in lower dimensional subspaces in a structured dictionary that can be learned from a set of representative training surfaces. We provide both theoretical and practical designs for achieving these goals. Specifically, we discuss details about the selection of limited optical views and the registration of partial optical images with a single preoperative MRI/CT scan. The design proposed in this paper is evaluated with both finite element modeling data and ex vivo experiments. The ex vivo test is conducted on fresh porcine kidneys using 3D MRI scans with 1.2 mm resolution and a portable laser scanner with an accuracy of 0.13 mm. Results show that the proposed method achieves a sub-3 mm spatial resolution in terms of Hausdorff distance when using only one preoperative MRI scan and the optical patch from the single-sided view of the kidney. The reconstruction frame rate is between 10 frames/s and 39 frames/s depending on the complexity of the test model.

Abstract 9746: Differential Impact of Dose-Related Chronic Alcohol Ingestion on Action Potential Upstroke, Systolic Myocardial Function and Cardiac Pro-inflammatory Factors mRNA Expression in Male C57BL/6 Mice

Background Cardiomyopathy elicited by ethanol or the toxic metabolites after chronic excessive alcohol intake had been well documented. However, to what extent of such dose-related chronic alcohol (Alc) ingestion on myocardial systolic performance and electrical disturbance remained unclear. Methods Totally 40 C57BL/6 male mice of 6 weeks old were fed with a liquid diet containing 4% (n=13) or 6% (n=14) alcohol and normal diet (CTRL, n=13) for 12 weeks. In vivo cardiac function was examined by echocardiography at baseline and before animal sacrifice. Optical mapping (Lecia MZ FLIII system, Heidelberg, Germany) and single cardiomyocyte patch clamp were used to assess conduction velocity of ventricular surface and action potential of single cardiomyocyte, respectively. Extent of myocardial macrophage infiltration and fibrosis were examined by immunostaining with the mRNA content of pro-inflammatory factors determined by real-time PCR. Results Both 4% and 6% Alc groups had reduced conduction velocity (47±3 cm/s and 28±8 cm/s vs Ctrl: 71±7 cm/s, p&lt;0.05)) and a more perturbated activation spread. Echocardiography demonstrated enlarged cardiac dimension and worsened fractional shortening in both Alc groups while only 6% Alc mice demonstrated a significant decline of systolic myocardial velocity (Ctrl vs 6%: 1.14±0.03 vs 0.97±0.03, p&lt;0.05). Reduced action potential upstroke velocity (Figure) and abnormal resting membrane potential were shown in both Alc groups. Markedly increased macrophage infiltration and fibrosis zone (6% vs Ctrl: 3.1±0.3 vs 1.3±0.1 mm 2 /cm 2 , p&lt;0.05) were accompanied by significantly elevated pro-inflammatory (including TNF-α, ΙL-6, and ΜΜP-2) factors mRNA expression only in 6% Alc mice. Conclusion These results showed a differential impact of myocardial electromechanical disturbance in response to dose-specific Alc ingestion and that overt inflammation response may start to take place in more severely damaged myocardium.

Depth Video Enhancement Based on Weighted Mode Filtering

This paper presents a novel approach for depth video enhancement. Given a high-resolution color video and its corresponding low-quality depth video, we improve the quality of the depth video by increasing its resolution and suppressing noise. For that, a weighted mode filtering method is proposed based on a joint histogram. When the histogram is generated, the weight based on color similarity between reference and neighboring pixels on the color image is computed and then used for counting each bin on the joint histogram of the depth map. A final solution is determined by seeking a global mode on the histogram. We show that the proposed method provides the optimal solution with respect to L(1) norm minimization. For temporally consistent estimate on depth video, we extend this method into temporally neighboring frames. Simple optical flow estimation and patch similarity measure are used for obtaining the high-quality depth video in an efficient manner. Experimental results show that the proposed method has outstanding performance and is very efficient, compared with existing methods. We also show that the temporally consistent enhancement of depth video addresses a flickering problem and improves the accuracy of depth video.

Linewidth reduction of a distributed-feedback diode laser using an all-fiber interferometer with short path imbalance

The linewidth of a distributed-feedback (DFB) diode laser at 1156 nm, of which free-running linewidth was 3 MHz, was reduced to 15 kHz using an all-fiber interferometer with 5-m-long path imbalance. Optical power loss and bandwidth limitation were negligible with this short optical fiber patch cord. This result was achieved without acoustic and vibration isolations, and the frequency lock could be maintained over weeks. In addition to its simplicity, compactness, robustness, and cost-effectiveness, this technique can be applied at any wavelength owing to the availability of DFB diode lasers and fiber-optic components.

Miniaturized optical system for atomic fountain clock

Using modularized components, we have built a miniaturized optical system for 87Rb atomic fountain clock that is fitted on an 80 cm × 60 cm optical breadboard. Compared with the conventional optical setup on the table, our system is more compact, more robust and miniaturized. Taking advantage of this system, laser beams are transmitted through eight optical fibre patch cords from the optical breadboard to an ultra high vacuum system. This optical setup has operated for five months in our fountain system and required no alignment.

Decay of polar cap patch

[1] We report an event in which a polar cap patch was detected with an all-sky imager (ASI) at Resolute Bay, Canada (74.73° N, 265.07° E; AACGM latitude 82.9°), on the nightside. The patch stopped its antisunward motion associated with a northward turning of interplanetary magnetic field and stayed within the field of view of the ASI for more than 1 h. When the patch stagnated, its luminosity decreased gradually, which allows us to investigate how the patch plasma decayed in a quantitative manner. The decay of the patch can be quantitatively explained by the loss through recombinations of O+ with ambient N2 and O2 molecules, if we assume the altitude of the optical patch to be around 295 km. The derived altitude of the patch around 295 km is much higher than the nominal value at 235 km obtained from the MSIS-E90 and IRI-2007 models, indicating that climatological models such as IRI are not suitable for describing the actual density profile of patches. This is probably because the loss process was much faster in the lower-altitude part of the patch; thus, the peak altitude of the patch increased as it traveled across the polar cap because of rapid recombination at the bottomside of the F region. This suggests that we should employ higher emission altitude when we investigate optical patches transported deep into the nightside polar cap. Such information is important when we compare the optical data with other instruments such as coherent radars and GPS scintillation measurements by mapping the all-sky image on the geographic coordinate system with an assumption of the patch emission altitude.

Temperature- and strain-independent torsion sensor using a fiber loop mirror based on suspended twin-core fiber

In this Letter, we present a fiber loop mirror configuration based on a suspended twin-core fiber for sensing applications. Using the suspended twin-core fiber, the fringe pattern is due to the differential optical patch of the light in the two cores associated with a refractive index difference of approximately 10(-3), which indicates an advantage of this approach compared with those based on high-birefringent fibers, namely, the possibility of using a small length of fiber. The sensing configuration was characterized for torsion, temperature, and strain. Using the fast Fourier transform technique, it is possible to obtain measurand-induced amplitude variations of the fringe pattern. The results obtained indicate the viability of a temperature- and strain-independent torsion sensor.

Magnetically Remote-Controlled Optical Sensor Spheres for Monitoring Oxygen or pH

Magnetic sensor macrospheres (MagSeMacs), i.e., stainless steel spheres coated with optical chemical sensors, are presented as an alternative to existing optical sensor patches and fiber-optical dip-probes. Such spheres can either be reversibly attached to the tip of an optical fiber (dip-probe) or trapped inside a vessel for read-out through the side wall. Moving the magnetic separator at the exterior enables measurements at varying positions with a single sensor. Moreover, the sensor’s replacement is rapid and contactless. We measured dissolved oxygen or pH in stirred liquids, rotating flasks, and 24-well plates with a SensorDish-reader device for parallel cell culture monitoring. In these applications, MagSeMacs proved to be advantageous over conventional sensor patches and magnetic optical sensor particles because of their magnetism, spherical shape, reflectance, and size. These properties resulted in strong but reversible fixation, magnetic remote-controllability, short response times, high signal intensities, and simplified handling.

Fabrication of low OH loss holey fibers with varying air hole sizes and their optical properties

We experimentally investigate a flexible fabrication technique for low OH and transmission losses holey fibers with a Ge-doped core and air holes in a silica cladding region. Versatile holey fibers of different size, pitch, and shape of air holes were achieved by controlling the temperature and heating time of the holey fiber preform. In addition, we suppress the OH loss of less than ∼0.323dB/km at 1383nm. After fabricating holey fibers, we measure their optical properties including cut-off wavelength, mode field diameter, splicing loss, dispersion, bending loss, and polarization dependent loss based on the size of air holes. The total transmission loss was measured to be ∼0.226dB/km at 1550nm by improving the fabrication process. After fabricating optical patch cord based on holey fibers, we measured the long-term stability of the fabricated holey fiber by using the temperature cycling technique for 24 and obtained low power fluctuation of 0.2dB. We achieve the high quality holey fiber with a low bending loss of ∼0.04dB/turn under a bending radius of 2.5mm at 1550nm. We also obtain a tunable band rejection filter with a number of bending turns.

On the Nonlinear Statistics of Range Image Patches

In [A. B. Lee, K. S. Pedersen, and D. Mumford, Int. J. Comput. Vis., 54 (2003), pp. 83–103], the authors study the distributions of $3\times3$ patches from optical images and from range images. In [G. Carlsson, T. Ishkanov, V. de Silva, and A. Zomorodian, Int. J. Comput. Vis., 76 (2008), pp. 1–12], the authors apply computational topological tools to the data set of optical patches studied by Lee, Pedersen, and Mumford and find geometric structures for high density subsets. One high density subset is called the primary circle and essentially consists of patches with a line separating a light and a dark region. In this paper, we apply the techniques of Carlsson et al. to range patches. By enlarging to $5\times5$ and $7\times7$ patches, we find core subsets that have the topology of the primary circle, suggesting a stronger connection between optical patches and range patches than was found by Lee, Pedersen, and Mumford.