Brugada Syndrome Deadly Effects of a MustNotMiss Diagnosis

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Fourier ptychography microscopy is a powerful tool for wide-field and high-spatial-resolution imaging. It can achieve a large field of view and high-spatial-resolution imaging with a low numerical aperture objective by capturing a series of low-resolution (LR) images that contain the information of different spatial frequencies and then stitching them together in the Fourier domain. Furthermore, the phase information of the object can also be recovered simultaneously. In this Letter, we propose a method to realize adaptive high-dynamic-range (HDR) LR image acquisition with a red, green, and blue camera, which needs only single exposure for each light-emitting diode (LED) illumination. According to the imaging principle of a color camera, the filter of each color channel still allows additional light within a certain wavelength range to pass through, but with a much smaller transmittance. By illuminating the sample with monochromatic light and combining the raw data from three color channels together, an HDR image corresponding to each LED illumination is obtained. The feasibility and good performance of our method are demonstrated by the experimental results.We present a scheme to realize precise discrimination of chiral molecules in a cavity. Assisted by additional laser pulses, cavity fields can evolve into different coherence states with contrary-sign displacements according to the handedness of molecules. Consequently, the handedness of molecules can be read out with homodyne measurement on the cavity, and the successful probability is nearly unity without very strong cavity fields. Numerical results show that the scheme is insensitive to errors, noise, and decoherence. Therefore, the scheme may provide helpful perspectives for accurate discrimination of chiral molecules.Modulation transfer spectroscopy is used to demonstrate absolute frequency stabilization of an 8.6-µm-wavelength quantum cascade laser against a sub-Doppler absorption of the CHF3 molecule. The obtained spectral emission properties are thoroughly characterized through a self-referenced optical frequency comb, stabilized against either a GPS-disciplined Rb clock or a 1.54-µm Er-fiber laser locked to a high-finesse ultra-low-expansion optical cavity. Fractional long-term stability and accuracy at a level of 4×10-12 (at 100 s) and 3×10-10, respectively, are demonstrated, along with an emission linewidth as narrow as 10 kHz for observation times of 0.1 s.Resonant frequency doubling of periodically phase-modulated single-frequency fiber laser is investigated as a method for power scaling of visible fiber lasers. Sinusoidal phase modulation is applied to generate few-frequency lasers at 1064 nm in the proof of principle experiments. By adjusting the modulation frequency to match the free spectral range of a doubling cavity, a resonant enhancement condition can be achieved and a near 30 W 532 nm laser is generated with a maximum conversion efficiency above 80%. The indistinguishable conversion efficiencies between the single-frequency and few-frequency cases prove the feasibility of the approach. Interesting spectral evolvement of the phase-modulated laser in second-harmonic generation is analyzed theoretically and observed in the experiment.Non-confocal adaptive optics scanning laser ophthalmoscopy (AOSLO) has enhanced the study of human retinal photoreceptors by providing complementary information to standard confocal AOSLO images. Previously we developed the first confocal handheld AOSLO (HAOSLO) capable of in vivo cone photoreceptor imaging in supine and non-cooperative patients. Here, we introduce the first multimodal (M-)HAOSLO for confocal and non-confocal split-detection (SD) imaging to allow for more comprehensive patient data collection. Aside from its unprecedented miniature size and weight, M-HAOSLO is also the first system to perform sensorless wavefront-corrected SD imaging of cone photoreceptors.We demonstrate a technique to compress spectral information in dual-comb spectroscopy that relies on subsampling of the electrical interferogram. It enables us to reduce the data sample rate by arbitrary factors directly in the sampling process or in post-processing of existing data. A demonstration code is provided.This publisher's note contains corrections to Opt. Lett.44, 4737 (2019) OPLEDP0146-959210.1364/OL.44.004737.High-purity silicon is a readily available material of utility in realizing a variety of long-wavelength optical and guided wave components. The transmittance of uncompensated for silicon is measured in the far- and mid-infrared regimes at room and cryogenic temperatures. The experimental and analysis techniques used to extract the refractive index from 100-1000cm-1 (100-10 µm) are presented, and the results are compared to the literature. An average refractive index below 300cm-1, n^(300K)=3.417+i8.9×10-5, which transitions in cooling to n^(10K)=3.389+i4.9×10-6, is observed.In this Letter, we propose a compact multimode fiber endoscope which employs wavefront shaping with a digital micromirror device (DMD). An automated single calibration step allows us to correct for optical misalignment, and the method achieves accurate focusing at various depths in the sample through rapid switching of holographic patterns by the DMD. The speed of calibration is one or two orders of magnitude faster than existing methods. The method, single calibration multimode fiber imaging (SCMFI), is compared with existing methods, and its performance is validated. read more We show a near diffraction limited focusing capability at imaging depths up to 110 µm with near constant lateral resolutions of 1.4 µm. Finally, we demonstrate the method for the imaging of small fluorescent beads embedded in a 3D matrix. The results indicate excellent power penetration and focusing performance. Combined with the high speed of SCMFI, this paves the way for volumetric tissue endoscopy at depth.In this Letter, we propose and demonstrate a practical optical-spatial-summing-based non-orthogonal multiple access (OSS-NOMA) technique for visible light communication (VLC) systems. This technique is innovative in adopting OSS in that the transmitter of OSS-NOMA VLC can be built upon commercial illuminating light emitting diodes (LEDs), free of LEDs' harmful nonlinearity. Unlike conventional NOMA VLC using analog components such as digital-to-analog converters and bias-T in the transmitter side, OSS-NOMA exploits only digital control signals to drive a LED array in forming optical power superposition for NOMA signals. We demonstrate that by simply switching different amounts of LED chips on or off, the proposed OSS-NOMA transmitter can deliver a fine-grained power allocation ratio ranging from 0.01 to one for two users. The implemented OSS-NOMA VLC prototype leveraging commercial components can achieve low bit error rates of ≤3.1×10-3 for two users at a data rate of 800 kbps, confirming the promising potential of this novel OSS-NOMA VLC for Internet of Things (IoT) applications.