Deep-UV microscopy, enabled by our microfluidic device, demonstrates a strong correlation between absolute neutrophil counts (ANC) and commercial hematology analyzer CBC results in patients with moderate to severe neutropenia and in healthy volunteers. This research forms the cornerstone for the creation of a portable and easily handled UV microscope system for tracking neutrophil levels, particularly in settings with limited resources, at-home, or on-site.

The rapid determination of terahertz orbital angular momentum (OAM) beams is demonstrated through the application of an atomic-vapor-based imaging technique. OAM modes, characterized by both azimuthal and radial indices, are produced by means of phase-only transmission plates. The optical CCD camera captures the far-field image of the beams after their transformation from terahertz to optical frequencies in an atomic vapor. Not only the spatial intensity profile, but also the self-interferogram of the beams, captured by imaging through a tilted lens, enables a direct determination of the sign and magnitude of the azimuthal index. Using this technique, the OAM mode of beams having a low intensity can be consistently measured with high accuracy in 10 milliseconds. This demonstration is projected to have extensive consequences for the intended deployment of terahertz OAM beams in microscopy and communication technologies.

An electro-optic (EO) switchable Nd:YVO4 laser, emitting at 1064 nm and 1342 nm wavelengths, is reported. This laser utilizes an aperiodically poled lithium niobate (APPLN) chip structured with aperiodic optical superlattice (AOS) technology. The APPLN component acts as a wavelength-sensitive electro-optic polarization controller within the polarization-sensitive laser amplification system, enabling the selection of diverse laser wavelengths through voltage manipulation. Modulation of the APPLN device by a voltage-pulse train alternating between VHQ (at which target laser lines experience gain) and VLQ (in which laser lines exhibit gain suppression) results in the generation of Q-switched laser pulses at dual wavelengths of 1064 and 1342 nanometers, single-wavelength 1064 nanometers, and single-wavelength 1342 nanometers, accompanied by non-phase-matched sum-frequency and second-harmonic generation at VHQ values of 0, 267, and 895 volts, respectively. Sacituzumab govitecan Simultaneous EO spectral switching and Q-switching mechanisms, to our knowledge, are novel and can enhance the processing speed and multiplexing capabilities of a laser for a wide range of applications.

We present a real-time picometer-scale interferometer that self-cancels noise, taking advantage of the unique spiral phase structure inherent in twisted light. A single cylindrical interference lens is used to create the twisted interferometer, allowing for simultaneous measurement on N phase-orthogonal single-pixel intensity pairs extracted from the daisy-flower interference pattern. Our system, employing a three orders of magnitude reduction in various noises compared to conventional single-pixel detection, provided the ability to achieve a sub-100 picometer resolution in real-time measurements of non-repetitive intracavity dynamic events. Additionally, the noise-canceling capacity of the twisted interferometer is statistically amplified by higher radial and azimuthal quantum numbers within the twisted light. Potential applications of the proposed scheme include precision metrology and the creation of analogous theoretical frameworks for twisted acoustic beams, electron beams, and matter waves.

A novel, as far as we are aware, coaxial double-clad-fiber (DCF) and graded-index (GRIN) fiberoptic Raman probe is reported to improve the efficacy of in vivo Raman measurements of epithelial tissue. With a 140-meter outer diameter, the ultra-thin DCF-GRIN fiberoptic Raman probe has a coaxial optical configuration for enhanced efficiency. A GRIN fiber is connected to the DCF, resulting in improved excitation/collection efficiency and depth-resolved selectivity. The DCF-GRIN Raman probe's capabilities are demonstrated in acquiring high-quality in vivo Raman spectra from a variety of oral tissues (e.g., buccal mucosa, labial mucosa, gingiva, mouth floor, palate, tongue), specifically encompassing both the fingerprint (800-1800 cm-1) and high-wavenumber (2800-3600 cm-1) regions within sub-second intervals. The DCF-GRIN fiberoptic Raman probe's capacity for high-sensitivity detection of subtle biochemical distinctions between various epithelial tissues in the oral cavity suggests its suitability for in vivo epithelial tissue diagnosis and characterization.

Organic nonlinear optical crystals are frequently utilized as highly efficient (>1%) terahertz (THz) radiation generators. One limitation of organic NLO crystals is the unique THz absorption in each crystal, thereby obstructing the generation of a strong, uniform, and broad emission spectrum. accident and emergency medicine By integrating THz pulses from the distinct crystals DAST and PNPA, we bridge spectral gaps, thereby producing a continuous spectrum spanning frequencies up to 5 THz. The peak-to-peak field strength, a consequence of combined pulses, expands its range from a baseline of 1 MV/cm to an elevated 19 MV/cm.

Traditional electronic computing systems utilize cascaded operations to bring about the execution of sophisticated strategies. For all-optical spatial analog computing, we present cascaded operations as a new methodology. Difficulties arise in meeting practical application needs in image recognition due to the limitations of the first-order operation's single function. Employing a cascade of two first-order differential units, all-optical second-order spatial differentiators are realized, successfully demonstrating image edge detection for both amplitude and phase targets. Our design demonstrates a prospective path for the fabrication of compact, multifunctional differentiation units and next-generation optical analog computing systems.

A novel design for a simple and energy-efficient photonic convolutional accelerator is proposed and experimentally verified, utilizing a monolithically integrated multi-wavelength distributed feedback semiconductor laser incorporating a superimposed sampled Bragg grating structure. The 22-kernel photonic convolutional accelerator, sliding its convolutional window vertically by 2 pixels, generates 100 images in real-time recognition, performing at 4448 GOPS. Moreover, the MNIST handwritten digit database yielded a real-time recognition task with a prediction accuracy reaching 84%. This work explores a compact and low-cost technique for the execution of photonic convolutional neural networks.

We, to the best of our knowledge, demonstrate the first tunable femtosecond mid-infrared optical parametric amplifier, based on a BaGa4Se7 crystal, with an exceptionally broad spectral range. The broad transparency range, high nonlinearity, and comparatively large bandgap of BGSe enable the 1030nm-pumped, 50 kHz repetition rate MIR OPA to produce an output spectrum that is tunable over an extremely wide spectral region, encompassing wavelengths from 3.7 to 17 micrometers. A quantum conversion efficiency of 5% is attained by the MIR laser source, where the maximum output power is 10mW at the center wavelength of 16 meters. To achieve straightforward power scaling in BGSe, one simply needs a more powerful pump with a large aperture size available. The BGSe OPA's operational parameters include a pulse width of 290 femtoseconds centered on a 16-meter location. Experimental results demonstrate the viability of BGSe crystal as a promising nonlinear material for the generation of fs MIR radiation, showing an ultra-broadband tunable spectral range via parametric downconversion, opening up opportunities for applications such as MIR ultrafast spectroscopy.

In the realm of terahertz (THz) technology, liquids appear to be a noteworthy area of exploration. However, the gathered THz electric field is hampered by the collection efficiency and the occurrence of saturation. A simplified simulation, analyzing the interference pattern from ponderomotive-force-induced dipoles, illustrates that plasma reshaping results in focused THz radiation collection. Utilizing a system of paired cylindrical lenses, a line-shaped plasma was created in cross-section. This led to the redirection of THz radiation, and the pump energy's dependence showed a quadratic trend, suggesting a substantial decrease in saturation. hepatic antioxidant enzyme Hence, the detected THz energy has been boosted by a factor of five. A straightforward, yet highly effective, demonstration is presented for the purpose of expanding the detectable range of THz signals emanating from liquids.

The low-cost, compact design and high-speed data acquisition of multi-wavelength phase retrieval make it a competitive solution for lensless holographic imaging. Nevertheless, the presence of phase wraps presents a distinctive obstacle to iterative reconstruction, frequently leading to algorithms with restricted applicability and amplified computational burdens. Our approach to multi-wavelength phase retrieval utilizes a projected refractive index framework, which directly retrieves the object's amplitude and unwrapped phase. Linearized general assumptions form an integral part of the forward model's design. The inverse problem formulation allows the incorporation of physical constraints and sparsity priors, ultimately enhancing image quality under noisy measurement conditions. A high-quality quantitative phase imaging system, based on a lensless on-chip holographic imaging system with three color LEDs, is experimentally demonstrated.

A new, long-lasting fiber grating configuration is introduced and successfully tested. The device's configuration is composed of a few micro air channels arranged along a single-mode fiber. Employing a femtosecond laser for the inscription of several groups of inner fiber waveguide arrays, followed by a hydrofluoric acid etching process, completes the device fabrication. The 600-meter length of the long-period fiber grating translates to just five grating periods. Based on our information, this long-period fiber grating is the shortest that has been reported. Remarkably, the device demonstrates a high refractive index sensitivity of 58708 nm/RIU (refractive index unit) across the refractive index range from 134 to 1365, coupled with a relatively small temperature sensitivity of only 121 pm/°C, thereby mitigating temperature cross-sensitivity.