Trajectories associated with early drinking alcohol milestones Interrelations between introduction and progression

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We present an erratum to correct an inadvertent error made during the calculations of the in-focus fluence of pulsed laser used to excite nanoparticles [Opt. Lett.44, 3162 (2019)OPLEDP0146-959210.1364/OL.44.003162] and to update the conclusion regarding laser safety limits achieved with this type of excitation.Platinum is reported as the main component of the substrate in surface plasmon microscopy of the metal-dielectric interface for small-angle measurements. In the absence of a narrow dip in the angular spectrum of platinum, the refractive index of the dielectric medium or the thickness of a deposited layer is proven deducible from the observed sharp peak, close to the critical angle. The sensitivities of refractive index and thickness measurements using platinum are compared with that of a gold surface plasmon resonance chip. Furthermore, the thickness of a structured layer of (3-Aminopropyl)triethoxysilane on the platinum substrate is measured to be 0.7 nm, demonstrating the high sensitivity of the technique.The maximum detectable vibration frequency of an optical frequency domain reflectometry (OFDR) system is limited by the tunable rate of the laser source. Unlike uniform sampling with the time-resolved method, the sampling frequency is randomly modulated so that the vibration signal applied on the interrogation fiber is sampled by a multi-frequency sub-Nyquist sampling method and reconstructed by the compressive sensing technique. First, we give a full treatment to prove that the proposed method has the same performance as the conventional method. Second, in a further proof-of-concept experiment, the measurable frequency of a sparse signal is achieved up to 200 Hz with a sweeping rate of 40 nm/s. This method can recover the vibration signal with sampling rates less than that required by the Nyquist sampling theory, which is a significant step toward a high-performance OFDR system, especially for evaluating the intrinsic frequency of the object's structural condition.We propose a simple method to control the topology of laser vortex solitons and their complexes in a wide-aperture laser with saturable absorption by means of weak coherent holding radiation. The holding radiation acting on initial "free" vortex solitons induces the appearance of new peripheral vortices and the splitting of multiple central vortices, as well as reconfiguration of energy flow topology. A wide variety of these stable vortex structures makes the scheme promising for topologically protected information processing.Structured light illumination, scanning along both horizontal and vertical directions, achieves more robust accuracy. By introducing the constraint of epipolar geometry, we previously proposed real-time 3D reconstruction using lookup tables; however, we only knew these offline derived tables were the combinations of the elements in calibration matrices of a camera and a projector, and suffered from long-time computation. In this Letter, by parameterizing the line perspectively mapping a 3D world coordinate into the camera and projector spaces, we propose to extend the epipolar analysis by defining phase and optical poles. Thus, we can geometrically address these parameters via analytic closed-form equations, with which we can (1) directly derive lookup tables in real time from the calibration matrices and (2) optimally reduce the number of tables from 11 to 5 to save much more memory space while further accelerating the processing rate. Experiments show that with the same level of accuracy, we significantly reduce the time to compute the lookup tables from more than 20 min to 20 ms, and increase the speed of computing point clouds from approximately 320 to 492 fps.We report on the study and generation of Ince-Gaussian beams in the spatially partially coherent regime. The inherent random fluctuations both in time and space of these partially coherent fields make their characterization difficult. WNK-IN-11 cost Our results show that the cross-correlation function (CCF) provides insight into the composition of the Ince-Gaussian beam, as well as into its spatial coherence structure and singularities. Our experimental findings are in very good agreement with the numerical simulations, particularly revealing a rich structure of nodal lines in the CCF.A scheme using cascaded silica microfibers is proposed for efficient third-harmonic (TH) generation. By tuning the phase difference via input pump power, the TH from the microfibers could overlap coherently, yielding great output enhancement. Conversion efficiency ∼20% is demonstrated analytically and numerically. Moreover, as the TH output features are dominated by behavior analogous to optical interference, the influence of random diameter deviation of each microfiber is reduced, and the conversion process could be well controlled.We report the first, to the best of our knowledge, demonstration of Grüneisen relaxation photoacoustic microscopy (GR-PAM) of lipid-rich tissue imaging at the 1.7 µm band, implemented with a high-energy thulium-doped fiber laser and a fiber-based delay line. GR-PAM enhances the image contrast by intensifying the region of strong absorbers and suppressing out-of-focus signals. Using GR-PAM to image swine-adipose tissue at 1725 nm, an 8.26-fold contrast enhancement is achieved in comparison to conventional PAM. GR-PAM at the 1.7 µm band is expected to be a useful tool for label-free high-resolution imaging of lipid-rich tissue, such as atherosclerotic plaque and nerves.In polarimetry, it is well known that measurement matrices based on spherical 2 designs optimize Stokes vector estimation in the presence of additive noise. We investigate the optimal matrices for estimation of the degree of polarization (DOP), the angle of polarization (AOP), and the ellipticity (EOP), which are nonlinear functions of the Stokes vector. We demonstrate that spherical 2 designs also optimize DOP and EOP estimation, but not AOP estimation, for which optimal structures consist of linear analyzers forming a regular polygon on the equator of the Poincaré sphere.Hyperspectral imaging has become a common technique in many different applications, enabling accurate identification of materials based on their optical properties; however, it requires complex and expensive technical implementation. A less expensive way to produce spectral data, spectral estimation, suffers from complex mathematics and limited accuracy. We introduce a novel, to the best of our knowledge, method where spectral reflectance curves can be reconstructed from the measured camera responses without complex mathematics. We have simulated the method with seven non-negative broadband transmission filters extracted from Munsell color data through principal component analysis and used sensitivity and noise levels characteristic of the Retiga 4000DC 12-bit monochrome camera. The method is sensitive to noise but produces sufficient reproduction accuracy even with six filters.