Our microfluidic deep-UV microscopy approach consistently delivers absolute neutrophil counts (ANC) highly correlated with commercial CBC results in patients suffering from moderate and severe neutropenia, as well as in healthy controls. This research establishes the groundwork for a portable, user-friendly UV microscopy system, ideal for counting neutrophils in resource-constrained, home-based, or point-of-care environments.
The rapid determination of terahertz orbital angular momentum (OAM) beams is demonstrated through the application of an atomic-vapor-based imaging technique. Utilizing phase-only transmission plates, OAM modes incorporating azimuthal and radial indices are formed. The beams' terahertz-to-optical transformation occurs within an atomic vapor environment, preceding their far-field imaging by an optical CCD camera. In conjunction with the spatial intensity profile, the self-interferogram of the beams, obtained through imaging with a tilted lens, allows for a direct readout of the sign and magnitude of the azimuthal index. This method enables the reliable readout of the OAM mode of low-power beams with high fidelity, occurring within 10 milliseconds. This demonstration is anticipated to create significant and widespread effects on the proposed applications of terahertz OAM beams within the fields of telecommunication and microscopy.
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, a wavelength-dependent electro-optic polarization controller in the laser system's polarization-dependent gain mechanism, enables selection between multiple laser spectra through voltage control. Operating the APPLN device with a voltage-pulse train fluctuating between VHQ, where target laser lines attain gain, and VLQ, where laser lines are suppressed, yields a distinctive laser system that produces Q-switched pulses at dual wavelengths of 1064 and 1342 nanometers, single-wavelength 1064 nanometers, and single-wavelength 1342 nanometers, alongside their non-phase-matched sum-frequency and second-harmonic generation occurring at VHQ voltages of 0, 267, and 895 volts, respectively. antibiotic expectations This novel, simultaneous EO spectral switching and Q-switching mechanism can, as far as we know, elevate a laser's processing speed and multiplexing capabilities, making it suitable for diverse applications.
By exploiting the unique spiral phase structure of twisted light, we exhibit a picometer-scale, real-time interferometer that effectively cancels noise. We utilize a single cylindrical interference lens to execute the twisted interferometer, allowing simultaneous measurement on N phase-orthogonal intensity pairs of single pixels originating from the petals of the daisy-flower-like interference pattern. Compared to conventional single-pixel detection, our setup yielded a three orders of magnitude reduction in noise, allowing sub-100 picometer resolution in the real-time measurement of non-repetitive intracavity dynamic events. Moreover, the twisted interferometer displays a statistically progressive enhancement in noise cancellation as the radial and azimuthal quantum numbers of the twisted light increase. The proposed scheme could find practical application in precision metrology, and furthermore, in the creation of analogous ideas 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. The Raman probe, a 140-meter-outer-diameter ultra-thin DCF-GRIN fiberoptic design, employs a coaxial optical system to optimize efficiency. Splicing a GRIN fiber onto the DCF enhances both excitation/collection efficiency and depth-resolved selectivity. Employing the DCF-GRIN Raman probe, we show the capability of obtaining high-quality in vivo Raman spectra from various oral tissues (buccal, labial, gingiva, mouth floor, palate, tongue) covering both the fingerprint (800-1800 cm-1) and high-wavenumber (2800-3600cm-1) regions, all within sub-second acquisition times. Oral cavity epithelial tissues, despite their subtle biochemical variations, can be distinguished with high sensitivity using the DCF-GRIN fiberoptic Raman probe, a potential tool for in vivo diagnosis and characterization.
The organic nonlinear optical crystals are a significant source of terahertz radiation, with an efficiency rating greater than one percent. 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. Almorexant supplier This work combines THz pulses emitted from both DAST and PNPA crystals, which are complementary, to seamlessly fill in the spectral gaps, resulting in a continuous spectrum reaching up to 5 THz. The peak-to-peak field strength, subjected to the combined effect of pulses, is increased from its initial value of 1 MV/cm to an amplified 19 MV/cm.
The implementation of sophisticated strategies in traditional electronic computing systems necessitates the use of cascaded operations. All-optical spatial analog computing is now enhanced with the concept of cascaded operations. The first-order operation's singular function struggles to satisfy the demands of practical image recognition applications. Second-order all-optical spatial differentiators are constructed by combining two first-order differential units, showcasing edge detection capabilities for both amplitude and phase images. The implementation of our approach may pave the way for the development of compact, multifunctional differentiators and advanced optical analog computing networks.
Through experimental demonstration, we propose a simple and energy-efficient photonic convolutional accelerator based on a monolithically integrated multi-wavelength distributed feedback semiconductor laser, which utilizes 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. A real-time recognition task concerning the MNIST database of handwritten digits yielded a prediction accuracy that is 84%. To realize photonic convolutional neural networks, this work introduces a compact and inexpensive method.
The first tunable femtosecond mid-infrared optical parametric amplifier, to our knowledge, is demonstrated, utilizing a BaGa4Se7 crystal and exhibiting an exceptionally wide spectral range. The BGSe material's broad transparency range, high nonlinearity, and relatively large bandgap are instrumental in enabling the 1030nm-pumped MIR OPA, operating at a 50 kHz repetition rate, to have an output spectrum that is tunable across a very wide spectral range, encompassing the region from 3.7 to 17 micrometers. The MIR laser source's maximum output power at a center wavelength of 16 meters is 10mW, yielding a quantum conversion efficiency of 5%. Power scaling in BGSe is readily accomplished through the application of a stronger pump, aided by a substantial aperture size. Regarding pulse width, the BGSe OPA provides support for 290 femtoseconds, centered at the 16-meter mark. Our experimental data confirm that BGSe crystal has the potential to act as a viable nonlinear crystal for the generation of fs MIR radiation, offering an impressively broad tunable spectral range via parametric downconversion, making it suitable for applications like MIR ultrafast spectroscopy.
In the realm of terahertz (THz) technology, liquids appear to be a noteworthy area of exploration. Nevertheless, the observed THz electric field is constrained by the proficiency of collection and the impact of saturation. Ponderomotive-force-induced dipole interference, as modeled in a simplified simulation, demonstrates that plasma reshaping leads to the concentration of THz radiation in the collection direction. Using a dual cylindrical lens system, a linearly shaped plasma was generated in the transverse plane, leading to the redirection of THz radiation. The dependence of the pump energy exhibits a quadratic behavior, signifying a significant attenuation of the saturation effect. Drug Screening Accordingly, the detected THz energy is multiplied by a factor of five. This demonstration highlights a simple, yet impactful strategy for achieving further scaling of detectable THz signals originating from liquid substances.
The capability of multi-wavelength phase retrieval to deliver a competitive lensless holographic imaging solution hinges on its cost-effective, compact construction and swift data acquisition. Yet, the existence of phase wraps stands as a unique impediment to iterative reconstruction, commonly producing algorithms with limited generalizability and heightened computational demands. In multi-wavelength phase retrieval, a projected refractive index framework is suggested, leading to the direct determination of the object's amplitude and unwrapped phase. Linearized general assumptions form an integral part of the forward model's design. Under noisy measurements, the quality of the image is assured by the use of physical constraints and sparsity priors, established within an inverse problem formulation. High-quality quantitative phase imaging is experimentally demonstrated using a lensless on-chip holographic imaging system incorporating three color LEDs.
A new, long-lasting fiber grating configuration is introduced and successfully tested. A single-mode fiber serves as the host for micro air channels that constitute the device's structural arrangement. The fabrication process necessitates a femtosecond laser for inscription of multiple arrays of fiber inner waveguides, followed by an etching step using hydrofluoric acid. 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.