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Dickey Gonzalez posted an update a month ago
Primary care practices throughout ten states encompassed federally qualified health centers, tribal health centers, rural health clinics, hospital/health system-owned entities, and academic medical centers, with a patient base distributed evenly as 55% urban and 45% rural. The examined population included primary care staff: physicians (n=13), residents (n=10), advanced practice providers (n=9), and administrators (n=10). Interviews assessed participant outlooks on cancer screening impediments and supports, necessary adjustments, and proposed future interventions. Cancer screening was hampered by delays in primary and specialty care access, shortages of medical personnel, insufficient protective equipment, patient resistance to in-person consultations, delays in postal services for home-testing kits, travel restrictions due to COVID-19 (particularly for patients crossing the Mexico-US border), and institutional rules (such as mandatory COVID-19 tests before screenings). Facilitators benefited from improved collaboration and care coordination, enabled by the pandemic, and gained extended telehealth appointment times for cancer screening discussions, exceeding the duration of in-person sessions. To adjust cancer screening procedures, delayed testing, triage of patients (prioritizing those overdue), telehealth consultations for discussing cancer screenings, mail-in test kits, coordinated cancer screenings (including supplying fecal immunochemical tests during cervical cancer screenings), and same-day screenings were implemented. To improve cancer screening outcomes during COVID-19, recommendations emphasized greater public health education efforts, the expansion of mail-home testing programs, and the widening of healthcare access, including the establishment of weekend clinics, to address the resulting patient backlogs. Innovative cancer screening adaptations were developed by primary care staff during the COVID-19 pandemic. The persistence of issues, including a backlog of patients, mandates further procedural implementations.
Integrated photonic devices depend upon multimode interference (MMI) power splitters, employing an interferometer design. Proposed to address the anticipated ‘capacity crunch’ in optical communications, integrated devices are capable of functioning in diverse spectral bands, including the conventional telecom window and the burgeoning 2-micron wavelength band, and are drawing substantial interest. A novel dual-band MMI-based 3 dB power splitter, operating within the 1550 nm and 2 micron bands, is demonstrated for the first time, as far as our knowledge goes. The fabricated power splitter’s excess losses are remarkably low at 0.21 dB and 0.32 dB, with corresponding 1 dB bandwidths for 1500-1600 nanometers and 1979-2050 nanometers, respectively.
Two 12-output power dividers utilizing multimode interference (MMI) are proposed and tested. The devices are characterized by ultra-compact design, simple fabrication processes, and low transmission losses. Through the application of Bezier curves, the design of MMI and output tapers is streamlined to support the creation of arbitrary ratio power splitters (ARPSs) and ultra-broadband dual-polarization power splitters (UDPSs). Across ARPS designs, experiments show that arbitrary power splitting ratios can be generated, resulting in an average excess loss of 0.17 dB at a wavelength of 1550 nm for fundamental TE polarization. For UDPSs, the experimental data underscores that effective lengths for fundamental TE and TM polarizations remain below -6.3dB and -4.4dB, respectively, over a comprehensive spectral bandwidth of 415nm (1260-1675nm). The projected area of the proposed devices, when excluding input straight waveguides, is anticipated to be between 10 and 25 square meters, and this proposed design offers substantial manufacturing tolerance.
This compact, continuous-wave, all-fiber cyan laser is, to our knowledge, newly reported for the first time. A 45-cm single-clad Pr3+-doped fluoride fiber, a 443-nm fiber-pigtail laser diode pump, and two custom-built dielectric-coated fiber-pigtail mirrors within the visible spectral region are incorporated into the all-fiber cavity. Direct downconversion lasing of cyan at 4915nm achieves a maximum output power of 975mW, exhibiting a slope efficiency of 237% and maintaining a power fluctuation below 0.41%. A cyan laser, constructed entirely of fiber, and exhibiting compactness, may hold substantial importance for widening the color range of laser displays and has potential applications in fluorescence imaging, underwater communication, and detection applications.
Long-range sensing, quantum information processing, and atomic clock technologies all demand a narrow linewidth laser that boasts high frequency stability and a diminutive form factor. High-performance noise-limited lasers (NLLs) have been demonstrated using Pound-Drever-Hall (PDH) lock or self-injection lock (SIL) techniques applied to a seed laser within a vacuum-stabilized Fabry-Perot (FP) cavity, characterized by an ultra-high Q factor. Complicated laboratory setups are frequently the result of the advanced stabilizing mechanisms and locking systems. This study presents a 67-mL volume nonlinear laser (NLL), created by incorporating single-mode diode laser output (SIL) into a miniature Fabry-Pérot (FP) cavity characterized by a high Q factor of 77108 and a 0.5-mL volume. This eliminates the bulky requirements of table-sized vacuum and isolation systems for thermal and vibration control. Our characterization of the NLL, achieved using a self-delayed heterodyne system, demonstrated a Lorentzian linewidth of 60 mHz, and an integrated linewidth of 80 Hz. DNASynthesis signal Frequency noise performance in this system is better than that observed in commercial NLLs and recently published hybrid-integrated NLL designs by SIL, which rely on high-Q on-chip ring resonators. Our endeavor represents a substantial advancement toward a deployable NLL of superior performance, facilitated by an ultrahigh-Q FP cavity.
Lasers emitting within the 2-3 micrometer wavelength spectrum, readily integrable with photonic platforms, hold significant potential for sensing applications. This approach leverages the combination of GaSb-based semiconductor gain chips and Si3N4 photonic integrated circuits, yielding a compelling platform. Employing the exceptional low-loss properties of Si3N4 waveguides, we showcase a hybrid laser system. This system integrates a GaSb gain chip with a tunable Si3N4 Vernier mirror. A laser operating at room temperature showcased a maximum output power of 15 milliwatts and a tunable wavelength range of 90 nanometers, varying between 1937 nanometers and 2026 nanometers. Several fundamental Si3N4 building blocks for photonic integrated circuits have also exhibited validated low-loss performance. The single-mode waveguide has a transmission loss of a low 0.15 dB per cm, the 90-degree bend exhibiting 0.008 dB loss, and the 50/50 Y-junction demonstrating an insertion loss of 0.075 dB.
We report a silicon-based microring avalanche photodiode (MRR-APD) with a very high responsivity (65 A/W), a dark current of 65 A, and an exceptional gain-bandwidth product of 798 GHz, operated at a reverse bias voltage of -736V. The high responsivity mechanisms have been modeled and investigated. Further, at 1310nm and -736V, open eye diagrams are functional up to a data rate of 20 Gb/s. We believe this device is the first low-cost, all-silicon APD with the potential to rival current commercial germanium and III-V-based photodetectors. The all-silicon APD stands to become a standard, black-box element in the component libraries of silicon photonics CMOS foundries.
The construction of self-directed radiation photonics systems hinges upon possessing a thorough grasp of the nonlinear attributes of the employed materials. This letter empirically demonstrates the vibrational mechanism governing the substantial, low-inertia cubic nonlinearity of water’s refractive index throughout the terahertz (THz) frequency regime. The liquid’s dominance is evident, as demonstrated by variations in its temperature. Analysis of the nonlinear refractive index in water jets, measured at THz frequencies and temperatures between 14°C and 21°C, corroborates theoretical models. The index demonstrates a range from 4×10⁻¹⁰ to 101×10⁻¹⁰ cm²/W, and displays an inertial time constant below 1 picosecond.
Theoretically, this letter analyzes cavity beam propagation within a gain medium and cavity, leveraging the rate equation and generalized Huygens’ integral, respectively. Within the transverse-mode-degenerate cavity configuration, spontaneous chaos and extreme events (EEs) were initiated by the interplay of transverse modes. An observed occurrence region, confined by variable pump power and cavity length, was noted. The continuous-wave Nd:YVO4 laser’s experimental outcomes harmonized with the previously mentioned numerical analyses. A laser’s reliance on gain effect necessitates that we consider EEs to be both universal and intrinsic within a properly aligned laser, if the transverse-mode competition conditions are fulfilled.
Light transport embodies the complete luminous transmission from the light source to the image sensor. In the realm of light transport, dual photography has seen considerable research interest, however, challenges such as lengthy acquisition durations, low signal-to-noise ratios, and the immense storage and processing burdens associated with copious measurement data hinder its progress. This letter describes a novel hardware system utilizing a flying-spot micro-electro-mechanical system (MEMS) modulated projector with an event camera to achieve dual photography. This facilitates 3D scanning of scenes featuring both line-of-sight (LoS) and non-line-of-sight (NLoS) visibility, including those containing transparent objects. Our methodology, employing event light transport, yielded depth extraction from scenes within the Line of Sight (LoS), along with the three-dimensional reconstruction of objects in Non-Line of Sight (NLoS) situations.