11/19/2024


Optoacoustic interaction can be strongly enhanced in tiny core fibers, and it holds significant potential for stable harmonic mode-locking at gigahertz (GHz) and higher repetition rate. In this Letter, we propose and demonstrate a microfiber-assisted GHz harmonic mode-locking fiber laser, which is achieved by the enhanced optomechanical coupling between cavity modes in microfiber with the waist length of ∼16cm and the waist diameter of ∼1.56µm. The repetition rates can be stably locked at 2.3828 GHz and predominately locked at 1.7852 GHz, corresponding to the frequencies of radial R01 and torsional-radial TR21 acoustic modes, respectively. Our results provide novel insight into the design of a high-repetition-rate laser source and the application of microfibers in the optomechanical field.Noninvasive, objective measurement of rod function is as significant as that of cone function, and for retinal diseases such as retinitis pigmentosa and age-related macular degeneration, rod function may be a more sensitive biomarker of disease progression and efficacy of treatment than cone function. Functional imaging of single human rod photoreceptors, however, has proven difficult because their small size and rapid functional response pose challenges for the resolution and speed of the imaging system. Here, we describe light-evoked, functional responses of human rods and cones, measured noninvasively using a synchronized adaptive optics optical coherence tomography (OCT) and scanning light ophthalmoscopy (SLO) system. The higher lateral resolution of the SLO images made it possible to confirm the identity of rods in the corresponding OCT volumes.It is of scientific significance to explore the terahertz radiation source with the performances of high power, tunable frequency, and controllable chirp for the realization of coherent control of quantum systems. How to realize frequency chirp control of terahertz synchrotron radiation is the last puzzle to be completed. In this Letter, we propose a method to control the radiation frequency chirp with precision. A novel photomixing scheme is presented to generate a longitudinally modulated laser pulse with non-uniform time intervals between the adjacent micro-peaks, which means that there is a chirp in the modulation frequency, and this chirp can be continuously tuned. https://www.selleckchem.com/products/nt157.html The interaction is made to occur between an electron beam and the modulated laser pulse in a modulator (an undulator tuned at the laser wavelength), then terahertz synchrotron radiation with the same spectrum characteristics as the modulated laser will be generated when the electron beam passes through the following bending magnet. We expect that this method will open a new way for the coherent control of quantum systems in the terahertz regime.Cavity-free lasing of N2+ induced by a femtosecond laser pulse at 800 nm is nearly totally suppressed by a delayed twin control pulse. We explain this surprising effect within the V-scheme of lasing without population inversion. A fast transfer of population between nitrogen ionic states X2Σg+ and A2Πu, induced by the second pulse, terminates the conditions for amplification in the system. The appearance of short lasing bursts at delays corresponding to revivals of rotational wave packets is explained along the same lines.This study considers the reflective characteristics of three-component Si/Al/Sc multilayer mirrors with a MoSi2 protective cap layer as candidates for telescopes for observation of the solar corona in the He I (λ=58.4nm) spectral line. At 58.4 nm, a peak reflectance of 32% and a spectral width at a half-maximum intensity of Δλ=5.4nm are obtained. The temporal stability of the reflectance at λ=58.4nm for Si/Al/Sc samples with a 6 nm thick MoSi2 cap layer is investigated during storage in air for 20 months.We report spatiotemporal pure-rotational coherent anti-Stokes Raman spectroscopy (CARS) in a one-dimensional imaging arrangement obtained with a single ultrafast regenerative amplifier system. The femtosecond pump/Stokes photon pairs, used for impulsive excitation, are delivered by an external compressor operating on a ∼35% beam split of the uncompressed amplifier output (2.5 mJ/pulse). The picosecond 1.2 mJ probe pulse is produced via the second-harmonic bandwidth compression (SHBC) of the ∼65% remainder of the amplifier output (4.5 mJ/pulse), which originates from the internal compressor. The two pump/Stokes and probe pulses are spatially, temporally, and repetition-wise correlated at the measurement, and the signal generation plane is relayed by a wide-field coherent imaging spectrometer onto the detector plane, which is refreshed at the same repetition rate as the ultrafast regenerative amplifier system. We demonstrate 1 kHz cinematographic 1D-CARS gas-phase thermometry across an unstable premixed methane/air flame-front, achieved with a single-shot precision less then 1% and accuracy less then 3%, 1.4 mm field of view, and an excellent less then 20µm line-spread function.BACKGROUND Prostate cancer (PCa) is considered to be the 4th most common cancer in males in the world. This study aimed to explore effects of atorvastatin on colony formation of PCa cells and radio-resistance of xenograft tumor models. MATERIAL AND METHODS PCa cell lines, including PC3, DU145, and Lncap, were treated with irradiation (4 Gy) and/or atorvastatin (6 μg/mL). Cells were divided into tumor cell group, irradiation treatment group (IR group) and irradiation+atorvastatin treatment group (IR-AS group). Xenograft tumor mouse model was established. Plate clone formation assay (multi-target/single-hit model) was conducted to evaluate colony formation. Flow cytometry analysis was employed to detect apoptosis. Interaction between Bcl-2 and MSH2 was evaluated with immuno-fluorescence assay. RESULTS According to the plate colony formation assay and multi-target/single-hit model, IR-treatment significantly suppressed colony formation in PCa cells (including PC3, DU145, and Lncap cells) compared to no-IR treated cells (P0.05). Atorvastatin administration (IR+AS group) significantly reduced tumor size of IR-treated PCa cells-induced xenograft tumor mice (P less then 0.05). Bcl-2 interacted with MSH2 both in tumor tissues of xenograft tumor mice. CONCLUSIONS Atorvastatin administration inhibited colony formation in PCa cells and enhanced effects of radiotherapy on tumor growth of xenograft tumor mice, which might be associated with interaction between Bcl-2 and MSH2 molecule.