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12/05/2024


We report a method to generate angularly polarized vector beams with a topological charge of one by rotating air holes to form two-dimensional photonic crystal (PC) cavities. The mode volume and resonance wavelength of these cavities are tuned from $0.33(\lambda /n)^3$0.33(λ/n)3 to $12(\lambda /n)^3$12(λ/n)3 and in a wide range of 400 nm, respectively, by controlling the range of fixed air holes near the center of the structure. As a benefit, the half-maximum divergence angles of the vector beam can be widely changed from 90° to $\sim60^\circ $∼60∘. By adjusting the shift direction of the air holes in the PC cavities, optical vector beams with different far-field morphology are obtained. The scheme provides not only an alternative method to generate optical vector beams, but also an effective strategy to control far-field morphology and polarizations, which holds promising applications such as optical microscopy and micro-manipulation.We demonstrated that ultrabroadband noise-like pulses (NLPs) spanning from below 1600 nm to beyond 2300 nm can be generated in Tm-doped fiber lasers enabled by an optical microfiber. Meanwhile, pronounced red light around 660 nm was also observed, which was attributed to the intracavity third harmonic generation (THG) of ultrashort pulses by harnessing the intermodal phase matching in the optical microfiber. As far as we know, it is the first time to simultaneously observe the ultrabroadband NLPs and the intracavity THG in ultrafast fiber lasers, and it is anticipated that these ultrabroadband NLPs can be adopted as a compact broadband source for optical spectroscopy around 2 µm and a wonderful potential seed for supercontinuum generation in the mid-infrared. Moreover, the THG of the intracavity high peak power NLPs in ultrafast fiber lasers provides a new kind of fiber-format visible light source.A nonlinear optical vortex coronagraph (n-OVC) based on sum-frequency generation (SFG) in a periodically poled lithium niobate (PPLN) crystal is presented. We demonstrate an n-OVC by mixing the image of an on-axis point source ($ \lambda _s = 1.6\;\unicodex00B5\rm m $λs=1.6µm) inside the PPLN crystal with a pump beam ($\lambda _p = 1064\;\rm nm$λp=1064nm) imprinted with a helical phase profile from a vector vortex mask (topological charge $l = 2$l=2). Due to quasi-phase matching and orbital angular momentum conservation, a coronagraphic image is produced at the SFG wavelength ($\lambda _\rm up\sim 630\;\rm nm$λup∼630nm). We validate that the n-OVC is tunable to signal wavelength but only requires a vortex mask operating at the pump wavelength. The acceptance bandwidth of the SFG process provides the n-OVC a degree of achromaticity even with a monochromatic vortex mask. The n-OVC exhibits an inner working angle of $ \sim \lambda _s/D$∼λs/D and an experimental contrast of $10^ - 4$10-4 at $3\lambda _s/D$3λs/D.It is still a technical challenge to obtain a 1.55 µm passively $Q$Q-switched $\rm Er^3 + /\rm Yb^3 + $Er3+/Yb3+ pulse laser with high energy and high repetition frequency, especially when it is end-pumped by a continuous-wave 0.98 µm diode laser. Benefitting from its long fluorescence lifetime of the $^4\rm I_13/2$4I13/2 upper laser level and high thermal conductivity, $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal may be an excellent gain medium for realizing a high energy and high repetition frequency 1.55 µm pulse laser. At a continuous-wave absorbed pump power of 6.1 W, a 1537 nm pulse laser with energy of 45.5 µJ, repetition frequency of 1.32 kHz, and duration of 25 ns was first, to the best of our knowledge, realized in an $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal.We report on a peculiar propagation of bosons loaded by a short Laguerre-Gaussian pulse in a nearly flat band of a lattice potential. Taking a system of exciton polaritons in a kagome lattice as an example, we show that an initially localized condensate propagates in a specific direction in space, if anisotropy is taken into account. This propagation consists of quantum jumps, collapses, and revivals of the whole compact states, and it persists given any direction of anisotropy. This property reveals its signatures in the tight-binding model, and, surprisingly, it is much more pronounced in a continuous model. Quantum revivals are robust to the repulsive interaction and finite lifetime of the particles. Since no magnetic field or spin-orbit interaction is required, this system provides a new kind of easily implementable optical logic.Structured illumination microscopy (SIM) is a powerful technique for providing super-resolution imaging, but its reconstruction algorithm, i.e., linear reconstruction structured illumination microscopy (LRSIM) algorithm in the Fourier domain, limits the imaging speed due to its computational effort. Here, we present a novel reconstruction algorithm that can directly process SIM data in the spatial domain. Compared to LRSIM, this approach uses the same number of frames to achieve a comparable resolution but with a much faster processing speed. Our algorithm was verified on both simulated and experimental data using sinusoidal pattern illumination. Moreover, this algorithm is also applicable for speckle pattern illumination.We report the experimental study of spectral modulations induced by a stimulated Raman scattering process in an all-fiber all-normal dispersion oscillator. With the use of dispersive Fourier transform, we recorded a series of single-shot spectra of consecutive laser pulses. The data indicate that the Raman process destabilizes the long-wavelength part of the laser pulse spectrum without disrupting the single-pulse generation regime. https://www.selleckchem.com/products/BIBR1532.html Our experiments revealed also that the oscillator displayed bistable operation for high pump powers. Two stable dissipative soliton mode-locked states were observed, together with output power hysteresis.Polarization imaging plays a crucial role in modern photonic applications such as remote sensing, material classification, and reconnaissance. A novel InGaAs focal plane array integrated with linear-array polarization grating is proposed and fabricated to meet the practical needs of near-infrared polarization imaging. In order to accurately evaluate the polarization performance of a fabricated detector, the improved test system is used to measure the transmittance and extinction ratio (ER). The results show that the detectivity reaches $1.06\; \times \;10^12\;\rm cm\cdot\rm Hz^1/2/\rm W$1.06×1012cm⋅Hz1/2/W, and the operable pixel factor is more than 99.8%. The transmittance of more than 55% and the ER of greater than 211 are realized, which indicates that the fabricated detector has excellent capability for near-infrared polarization imaging.

11/22/2024


We report a method to generate angularly polarized vector beams with a topological charge of one by rotating air holes to form two-dimensional photonic crystal (PC) cavities. The mode volume and resonance wavelength of these cavities are tuned from $0.33(\lambda /n)^3$0.33(λ/n)3 to $12(\lambda /n)^3$12(λ/n)3 and in a wide range of 400 nm, respectively, by controlling the range of fixed air holes near the center of the structure. As a benefit, the half-maximum divergence angles of the vector beam can be widely changed from 90° to $\sim60^\circ $∼60∘. By adjusting the shift direction of the air holes in the PC cavities, optical vector beams with different far-field morphology are obtained. The scheme provides not only an alternative method to generate optical vector beams, but also an effective strategy to control far-field morphology and polarizations, which holds promising applications such as optical microscopy and micro-manipulation.We demonstrated that ultrabroadband noise-like pulses (NLPs) spanning from below 1600 nm to beyond 2300 nm can be generated in Tm-doped fiber lasers enabled by an optical microfiber. Meanwhile, pronounced red light around 660 nm was also observed, which was attributed to the intracavity third harmonic generation (THG) of ultrashort pulses by harnessing the intermodal phase matching in the optical microfiber. As far as we know, it is the first time to simultaneously observe the ultrabroadband NLPs and the intracavity THG in ultrafast fiber lasers, and it is anticipated that these ultrabroadband NLPs can be adopted as a compact broadband source for optical spectroscopy around 2 µm and a wonderful potential seed for supercontinuum generation in the mid-infrared. Moreover, the THG of the intracavity high peak power NLPs in ultrafast fiber lasers provides a new kind of fiber-format visible light source.A nonlinear optical vortex coronagraph (n-OVC) based on sum-frequency generation (SFG) in a periodically poled lithium niobate (PPLN) crystal is presented. We demonstrate an n-OVC by mixing the image of an on-axis point source ($ \lambda _s = 1.6\;\unicodex00B5\rm m $λs=1.6µm) inside the PPLN crystal with a pump beam ($\lambda _p = 1064\;\rm nm$λp=1064nm) imprinted with a helical phase profile from a vector vortex mask (topological charge $l = 2$l=2). Due to quasi-phase matching and orbital angular momentum conservation, a coronagraphic image is produced at the SFG wavelength ($\lambda _\rm up\sim 630\;\rm nm$λup∼630nm). We validate that the n-OVC is tunable to signal wavelength but only requires a vortex mask operating at the pump wavelength. The acceptance bandwidth of the SFG process provides the n-OVC a degree of achromaticity even with a monochromatic vortex mask. The n-OVC exhibits an inner working angle of $ \sim \lambda _s/D$∼λs/D and an experimental contrast of $10^ - 4$10-4 at $3\lambda _s/D$3λs/D.It is still a technical challenge to obtain a 1.55 µm passively $Q$Q-switched $\rm Er^3 + /\rm Yb^3 + $Er3+/Yb3+ pulse laser with high energy and high repetition frequency, especially when it is end-pumped by a continuous-wave 0.98 µm diode laser. Benefitting from its long fluorescence lifetime of the $^4\rm I_13/2$4I13/2 upper laser level and high thermal conductivity, $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal may be an excellent gain medium for realizing a high energy and high repetition frequency 1.55 µm pulse laser. At a continuous-wave absorbed pump power of 6.1 W, a 1537 nm pulse laser with energy of 45.5 µJ, repetition frequency of 1.32 kHz, and duration of 25 ns was first, to the best of our knowledge, realized in an $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal.We report on a peculiar propagation of bosons loaded by a short Laguerre-Gaussian pulse in a nearly flat band of a lattice potential. Taking a system of exciton polaritons in a kagome lattice as an example, we show that an initially localized condensate propagates in a specific direction in space, if anisotropy is taken into account. This propagation consists of quantum jumps, collapses, and revivals of the whole compact states, and it persists given any direction of anisotropy. This property reveals its signatures in the tight-binding model, and, surprisingly, it is much more pronounced in a continuous model. Quantum revivals are robust to the repulsive interaction and finite lifetime of the particles. Since no magnetic field or spin-orbit interaction is required, this system provides a new kind of easily implementable optical logic.Structured illumination microscopy (SIM) is a powerful technique for providing super-resolution imaging, but its reconstruction algorithm, i.e., linear reconstruction structured illumination microscopy (LRSIM) algorithm in the Fourier domain, limits the imaging speed due to its computational effort. Here, we present a novel reconstruction algorithm that can directly process SIM data in the spatial domain. Compared to LRSIM, this approach uses the same number of frames to achieve a comparable resolution but with a much faster processing speed. Our algorithm was verified on both simulated and experimental data using sinusoidal pattern illumination. Moreover, this algorithm is also applicable for speckle pattern illumination.We report the experimental study of spectral modulations induced by a stimulated Raman scattering process in an all-fiber all-normal dispersion oscillator. With the use of dispersive Fourier transform, we recorded a series of single-shot spectra of consecutive laser pulses. The data indicate that the Raman process destabilizes the long-wavelength part of the laser pulse spectrum without disrupting the single-pulse generation regime. https://www.selleckchem.com/products/eft-508.html Our experiments revealed also that the oscillator displayed bistable operation for high pump powers. Two stable dissipative soliton mode-locked states were observed, together with output power hysteresis.Polarization imaging plays a crucial role in modern photonic applications such as remote sensing, material classification, and reconnaissance. A novel InGaAs focal plane array integrated with linear-array polarization grating is proposed and fabricated to meet the practical needs of near-infrared polarization imaging. In order to accurately evaluate the polarization performance of a fabricated detector, the improved test system is used to measure the transmittance and extinction ratio (ER). The results show that the detectivity reaches $1.06\; \times \;10^12\;\rm cm\cdot\rm Hz^1/2/\rm W$1.06×1012cm⋅Hz1/2/W, and the operable pixel factor is more than 99.8%. The transmittance of more than 55% and the ER of greater than 211 are realized, which indicates that the fabricated detector has excellent capability for near-infrared polarization imaging.

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.

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12/05/2024


We report a method to generate angularly polarized vector beams with a topological charge of one by rotating air holes to form two-dimensional photonic crystal (PC) cavities. The mode volume and resonance wavelength of these cavities are tuned from $0.33(\lambda /n)^3$0.33(λ/n)3 to $12(\lambda /n)^3$12(λ/n)3 and in a wide range of 400 nm, respectively, by controlling the range of fixed air holes near the center of the structure. As a benefit, the half-maximum divergence angles of the vector beam can be widely changed from 90° to $\sim60^\circ $∼60∘. By adjusting the shift direction of the air holes in the PC cavities, optical vector beams with different far-field morphology are obtained. The scheme provides not only an alternative method to generate optical vector beams, but also an effective strategy to control far-field morphology and polarizations, which holds promising applications such as optical microscopy and micro-manipulation.We demonstrated that ultrabroadband noise-like pulses (NLPs) spanning from below 1600 nm to beyond 2300 nm can be generated in Tm-doped fiber lasers enabled by an optical microfiber. Meanwhile, pronounced red light around 660 nm was also observed, which was attributed to the intracavity third harmonic generation (THG) of ultrashort pulses by harnessing the intermodal phase matching in the optical microfiber. As far as we know, it is the first time to simultaneously observe the ultrabroadband NLPs and the intracavity THG in ultrafast fiber lasers, and it is anticipated that these ultrabroadband NLPs can be adopted as a compact broadband source for optical spectroscopy around 2 µm and a wonderful potential seed for supercontinuum generation in the mid-infrared. Moreover, the THG of the intracavity high peak power NLPs in ultrafast fiber lasers provides a new kind of fiber-format visible light source.A nonlinear optical vortex coronagraph (n-OVC) based on sum-frequency generation (SFG) in a periodically poled lithium niobate (PPLN) crystal is presented. We demonstrate an n-OVC by mixing the image of an on-axis point source ($ \lambda _s = 1.6\;\unicodex00B5\rm m $λs=1.6µm) inside the PPLN crystal with a pump beam ($\lambda _p = 1064\;\rm nm$λp=1064nm) imprinted with a helical phase profile from a vector vortex mask (topological charge $l = 2$l=2). Due to quasi-phase matching and orbital angular momentum conservation, a coronagraphic image is produced at the SFG wavelength ($\lambda _\rm up\sim 630\;\rm nm$λup∼630nm). We validate that the n-OVC is tunable to signal wavelength but only requires a vortex mask operating at the pump wavelength. The acceptance bandwidth of the SFG process provides the n-OVC a degree of achromaticity even with a monochromatic vortex mask. The n-OVC exhibits an inner working angle of $ \sim \lambda _s/D$∼λs/D and an experimental contrast of $10^ - 4$10-4 at $3\lambda _s/D$3λs/D.It is still a technical challenge to obtain a 1.55 µm passively $Q$Q-switched $\rm Er^3 + /\rm Yb^3 + $Er3+/Yb3+ pulse laser with high energy and high repetition frequency, especially when it is end-pumped by a continuous-wave 0.98 µm diode laser. Benefitting from its long fluorescence lifetime of the $^4\rm I_13/2$4I13/2 upper laser level and high thermal conductivity, $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal may be an excellent gain medium for realizing a high energy and high repetition frequency 1.55 µm pulse laser. At a continuous-wave absorbed pump power of 6.1 W, a 1537 nm pulse laser with energy of 45.5 µJ, repetition frequency of 1.32 kHz, and duration of 25 ns was first, to the best of our knowledge, realized in an $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal.We report on a peculiar propagation of bosons loaded by a short Laguerre-Gaussian pulse in a nearly flat band of a lattice potential. Taking a system of exciton polaritons in a kagome lattice as an example, we show that an initially localized condensate propagates in a specific direction in space, if anisotropy is taken into account. This propagation consists of quantum jumps, collapses, and revivals of the whole compact states, and it persists given any direction of anisotropy. This property reveals its signatures in the tight-binding model, and, surprisingly, it is much more pronounced in a continuous model. Quantum revivals are robust to the repulsive interaction and finite lifetime of the particles. Since no magnetic field or spin-orbit interaction is required, this system provides a new kind of easily implementable optical logic.Structured illumination microscopy (SIM) is a powerful technique for providing super-resolution imaging, but its reconstruction algorithm, i.e., linear reconstruction structured illumination microscopy (LRSIM) algorithm in the Fourier domain, limits the imaging speed due to its computational effort. Here, we present a novel reconstruction algorithm that can directly process SIM data in the spatial domain. Compared to LRSIM, this approach uses the same number of frames to achieve a comparable resolution but with a much faster processing speed. Our algorithm was verified on both simulated and experimental data using sinusoidal pattern illumination. Moreover, this algorithm is also applicable for speckle pattern illumination.We report the experimental study of spectral modulations induced by a stimulated Raman scattering process in an all-fiber all-normal dispersion oscillator. With the use of dispersive Fourier transform, we recorded a series of single-shot spectra of consecutive laser pulses. The data indicate that the Raman process destabilizes the long-wavelength part of the laser pulse spectrum without disrupting the single-pulse generation regime. https://www.selleckchem.com/products/BIBR1532.html Our experiments revealed also that the oscillator displayed bistable operation for high pump powers. Two stable dissipative soliton mode-locked states were observed, together with output power hysteresis.Polarization imaging plays a crucial role in modern photonic applications such as remote sensing, material classification, and reconnaissance. A novel InGaAs focal plane array integrated with linear-array polarization grating is proposed and fabricated to meet the practical needs of near-infrared polarization imaging. In order to accurately evaluate the polarization performance of a fabricated detector, the improved test system is used to measure the transmittance and extinction ratio (ER). The results show that the detectivity reaches $1.06\; \times \;10^12\;\rm cm\cdot\rm Hz^1/2/\rm W$1.06×1012cm⋅Hz1/2/W, and the operable pixel factor is more than 99.8%. The transmittance of more than 55% and the ER of greater than 211 are realized, which indicates that the fabricated detector has excellent capability for near-infrared polarization imaging.

11/22/2024


We report a method to generate angularly polarized vector beams with a topological charge of one by rotating air holes to form two-dimensional photonic crystal (PC) cavities. The mode volume and resonance wavelength of these cavities are tuned from $0.33(\lambda /n)^3$0.33(λ/n)3 to $12(\lambda /n)^3$12(λ/n)3 and in a wide range of 400 nm, respectively, by controlling the range of fixed air holes near the center of the structure. As a benefit, the half-maximum divergence angles of the vector beam can be widely changed from 90° to $\sim60^\circ $∼60∘. By adjusting the shift direction of the air holes in the PC cavities, optical vector beams with different far-field morphology are obtained. The scheme provides not only an alternative method to generate optical vector beams, but also an effective strategy to control far-field morphology and polarizations, which holds promising applications such as optical microscopy and micro-manipulation.We demonstrated that ultrabroadband noise-like pulses (NLPs) spanning from below 1600 nm to beyond 2300 nm can be generated in Tm-doped fiber lasers enabled by an optical microfiber. Meanwhile, pronounced red light around 660 nm was also observed, which was attributed to the intracavity third harmonic generation (THG) of ultrashort pulses by harnessing the intermodal phase matching in the optical microfiber. As far as we know, it is the first time to simultaneously observe the ultrabroadband NLPs and the intracavity THG in ultrafast fiber lasers, and it is anticipated that these ultrabroadband NLPs can be adopted as a compact broadband source for optical spectroscopy around 2 µm and a wonderful potential seed for supercontinuum generation in the mid-infrared. Moreover, the THG of the intracavity high peak power NLPs in ultrafast fiber lasers provides a new kind of fiber-format visible light source.A nonlinear optical vortex coronagraph (n-OVC) based on sum-frequency generation (SFG) in a periodically poled lithium niobate (PPLN) crystal is presented. We demonstrate an n-OVC by mixing the image of an on-axis point source ($ \lambda _s = 1.6\;\unicodex00B5\rm m $λs=1.6µm) inside the PPLN crystal with a pump beam ($\lambda _p = 1064\;\rm nm$λp=1064nm) imprinted with a helical phase profile from a vector vortex mask (topological charge $l = 2$l=2). Due to quasi-phase matching and orbital angular momentum conservation, a coronagraphic image is produced at the SFG wavelength ($\lambda _\rm up\sim 630\;\rm nm$λup∼630nm). We validate that the n-OVC is tunable to signal wavelength but only requires a vortex mask operating at the pump wavelength. The acceptance bandwidth of the SFG process provides the n-OVC a degree of achromaticity even with a monochromatic vortex mask. The n-OVC exhibits an inner working angle of $ \sim \lambda _s/D$∼λs/D and an experimental contrast of $10^ - 4$10-4 at $3\lambda _s/D$3λs/D.It is still a technical challenge to obtain a 1.55 µm passively $Q$Q-switched $\rm Er^3 + /\rm Yb^3 + $Er3+/Yb3+ pulse laser with high energy and high repetition frequency, especially when it is end-pumped by a continuous-wave 0.98 µm diode laser. Benefitting from its long fluorescence lifetime of the $^4\rm I_13/2$4I13/2 upper laser level and high thermal conductivity, $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal may be an excellent gain medium for realizing a high energy and high repetition frequency 1.55 µm pulse laser. At a continuous-wave absorbed pump power of 6.1 W, a 1537 nm pulse laser with energy of 45.5 µJ, repetition frequency of 1.32 kHz, and duration of 25 ns was first, to the best of our knowledge, realized in an $\rm Er\rm Yb\rm Lu_2\rm Si_2\rm O_7$ErYbLu2Si2O7 crystal.We report on a peculiar propagation of bosons loaded by a short Laguerre-Gaussian pulse in a nearly flat band of a lattice potential. Taking a system of exciton polaritons in a kagome lattice as an example, we show that an initially localized condensate propagates in a specific direction in space, if anisotropy is taken into account. This propagation consists of quantum jumps, collapses, and revivals of the whole compact states, and it persists given any direction of anisotropy. This property reveals its signatures in the tight-binding model, and, surprisingly, it is much more pronounced in a continuous model. Quantum revivals are robust to the repulsive interaction and finite lifetime of the particles. Since no magnetic field or spin-orbit interaction is required, this system provides a new kind of easily implementable optical logic.Structured illumination microscopy (SIM) is a powerful technique for providing super-resolution imaging, but its reconstruction algorithm, i.e., linear reconstruction structured illumination microscopy (LRSIM) algorithm in the Fourier domain, limits the imaging speed due to its computational effort. Here, we present a novel reconstruction algorithm that can directly process SIM data in the spatial domain. Compared to LRSIM, this approach uses the same number of frames to achieve a comparable resolution but with a much faster processing speed. Our algorithm was verified on both simulated and experimental data using sinusoidal pattern illumination. Moreover, this algorithm is also applicable for speckle pattern illumination.We report the experimental study of spectral modulations induced by a stimulated Raman scattering process in an all-fiber all-normal dispersion oscillator. With the use of dispersive Fourier transform, we recorded a series of single-shot spectra of consecutive laser pulses. The data indicate that the Raman process destabilizes the long-wavelength part of the laser pulse spectrum without disrupting the single-pulse generation regime. https://www.selleckchem.com/products/eft-508.html Our experiments revealed also that the oscillator displayed bistable operation for high pump powers. Two stable dissipative soliton mode-locked states were observed, together with output power hysteresis.Polarization imaging plays a crucial role in modern photonic applications such as remote sensing, material classification, and reconnaissance. A novel InGaAs focal plane array integrated with linear-array polarization grating is proposed and fabricated to meet the practical needs of near-infrared polarization imaging. In order to accurately evaluate the polarization performance of a fabricated detector, the improved test system is used to measure the transmittance and extinction ratio (ER). The results show that the detectivity reaches $1.06\; \times \;10^12\;\rm cm\cdot\rm Hz^1/2/\rm W$1.06×1012cm⋅Hz1/2/W, and the operable pixel factor is more than 99.8%. The transmittance of more than 55% and the ER of greater than 211 are realized, which indicates that the fabricated detector has excellent capability for near-infrared polarization imaging.

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.

11/18/2024


Motivated by recent observations of ergodicity breaking due to Hilbert space fragmentation in 1D Fermi-Hubbard chains with a tilted potential [Scherg et al., arXiv2010.12965], we show that the same system also hosts quantum many-body scars in a regime U≈Δ≫J at electronic filling factor ν=1. We numerically demonstrate that the scarring phenomenology in this model is similar to other known realizations such as Rydberg atom chains, including persistent dynamical revivals and ergodicity-breaking many-body eigenstates. At the same time, we show that the mechanism of scarring in the Fermi-Hubbard model is different from other examples in the literature the scars originate from a subgraph, representing a free spin-1 paramagnet, which is weakly connected to the rest of the Hamiltonian's adjacency graph. Our work demonstrates that correlated fermions in tilted optical lattices provide a platform for understanding the interplay of many-body scarring and other forms of ergodicity breaking, such as localization and Hilbert space fragmentation.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into a pandemic of unprecedented scale. This coronavirus enters cells by the interaction of the receptor binding domain (RBD) with the human angiotensin-converting enzyme 2 receptor (hACE2). In this study, we employed a rational structure-based design to propose 22-mer stapled peptides using the structure of the hACE2 α1 helix as a template. These peptides were designed to retain the α-helical character of the natural structure, to enhance binding affinity, and to display a better solubility profile compared to other designed peptides available in the literature. We employed different docking strategies (PATCHDOCK and ZDOCK) followed by a double-step refinement process (FIBERDOCK) to rank our peptides, followed by stability analysis/evaluation of the interaction profile of the best docking predictions using a 500 ns molecular dynamics (MD) simulation, and a further binding affinity analysis by molecular mechanics with generalized Born and surface area (MM/GBSA) method. Our most promising stapled peptides presented a stable profile and could retain important interactions with the RBD in the presence of the E484K RBD mutation. We predict that these peptides can bind to the viral RBD with similar potency to the control NYBSP-4 (a 30-mer experimentally proven peptide inhibitor). Furthermore, our study provides valuable information for the rational design of double-stapled peptide as inhibitors of SARS-CoV-2 infection.CoMo sulfides are typical catalysts for selective hydrodeoxygenation (HDO) of phenolics to aromatics which is important in bio-oil upgrading. However, it is still a challenge to promote the intrinsic activity of Co-MoS2 catalysts. Defect chemistry provides a good option to improve surface reactivity in catalysis. In this work, we report a facile H2O2 etching method to tailor the concentration of surface acidic sites. https://www.selleckchem.com/products/guanosine-5-triphosphate-trisodium-salt.html The molar ratio of H2O2/MoS2 can be altered to tune sulfur defects on the MoS2 surface for stabilizing Co species to form CoMoS active sites. The optimized Co-MoS2-2 catalyst, with the highest concentration of acidic sites, exhibits 3.4 times higher activity than the Co-MoS2-0 sample in the HDO of p-cresol to toluene. It is also found the HDO activity shows a linear relationship with the amount of surface acid (both Lewis and Brønsted acid) over the Co-MoS2-x catalysts. We believe that the understanding of the role of surface acidity would provide new opportunities for the rational design of efficient Co-MoS2 catalysts.Nitrogen dioxide, NO2, is a free radical composed of the two most abundant elements in Earth's atmosphere, nitrogen and oxygen, and is relevant to atmospheric and combustion chemistry. The electronic structure of even its lowest-lying states is remarkably complex, with various conical intersections and Renner-Teller pairings, giving rise to complex and perturbed vibronic states. Here we report some analysis of the 18 molecular states of doublet spin-multiplicity formed by combining ground-state N(4Su) and O(3Pg) atoms. Three-dimensional potential energy surfaces were fit at the MRCI(Q)-F12/VTZ-F12 level, describing the lowest four (X̃, Ã, B̃, and C̃) electronic states. A properties-based diabatization procedure was applied to accommodate the intersections, producing energies in a quasidiabatic representation and yielding couplings that were also fit into surfaces. The low-lying vibrational levels on the ground X̃ state were computed and compared with experimental measurements. Compared to experiment, the lowest 125 calculated vibrational levels (up to 8500 cm-1 above the zero-point energy) have a root-mean-squared error of 16.5 cm-1. In addition, dipole moments for each of the lowest four electronic states-and the transition dipoles between them-were also computed and fit. With the coupled energy and dipole surfaces, the electronic spectrum was calculated in absolute intensity and compared with experimental measurements. Detailed structure in the experimental spectrum was successfully reproduced, and the total integrated intensity matches experiment to an accuracy of ∼1.5% with no empirical adjustments.In recent years, considerable breakthroughs have been achieved in the explored photodetectors with improved performance and stability. However, such devices suffer from the drifting parameters (photoresponsivity, response time, and specific detectivity) in the case of evident operating temperature changes. Here, a double perovskite Cs2NaBiCl6-based ultraviolet (UV) photodetector is developed free from thermal disturbance, exhibiting a steady photoresponsivity (≈ 67.98 mA/W) and response time (≈ 16.42 ms) within a wide temperature range (from 273 to 333 K). Further studies demonstrate that the stability of the crystal structure endows the superior photodetection capability. This result unambiguously highlights the great potential of such double perovskite Cs2NaBiCl6 compound as an environmentally friendly alternative for UV photodetectors.Based on the energy conservation approach, this study develops a universal model to predict the maximum spreading factor of liquid droplet impact on a smooth solid surface. Validated with the present simulations and experiments in the literature, this model effectively overcomes the limitation of previous models in the viscous regime and greatly reduces the computing errors from over 30% to below 6%. It is demonstrated that the underestimated maximum spreading factor by previous models results from the overestimation of viscous dissipation. By replacing the conventional model of spreading time, tm = 8D0/3U0, with a more precise one, tm = 1.47τiWe-0.44, the formulation to compute the viscous dissipation of entire spreading is improved. Finally, we examine the applicability of present model in the capillary regime and good performance is also shown.

11/02/2024





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** Introduction **.



In today's competitive company landscape, procurement plays a crucial function in driving operational efficiency and productivity. https://atavi.com/share/wx7puuz1bwr31 dives deeper into sophisticated purchase strategies, gearing up experts with the abilities and insights to take advantage of SAP ERP's robust capabilities. This guide will discover the vital takeaways from this innovative SAP ERP course and demonstrate how it can encourage procurement groups to excel.



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### 1. ** Advanced Purchase Procedures with SAP ERP **.



** Key Emphasizes **:.



** Automated Sourcing & Vendor Monitoring **: Streamline vendor option and connection administration by making use of SAP ERP's automated sourcing features. The training course covers advanced sourcing methods, enabling participants to maximize vendor communications and attain cost-effective results.
** Enhanced Contract Management **: Discover just how to develop, keep an eye on, and manage agreements within SAP ERP. TSCM52 supplies comprehensive understandings into automating agreement revivals and tracking conformity, making sure better control over purchase commitments.

** Advantages **: Mastering these tools leads to minimized cycle times, boosted supplier efficiency, and considerable price financial savings.



### 2. ** Enhancing Order Management **.



** Secret Emphasizes **:.



** Automated Order (PO) Development **: Explore techniques to automate PO development based upon inventory and need data, reducing manual intervention.
** PO Authorization Workflow Optimization **: Learn to set up personalized approval operations in SAP ERP, ensuring purchase conformity and enhanced accountability at every stage.

** Advantages **: These abilities encourage procurement teams to process orders much faster, lower mistakes, and keep uniformity throughout all PO processes.



### 3. ** Supply and Stock Monitoring **.



** Trick Highlights **:.



** Supply Optimization Techniques **: Learn advanced stock administration approaches to stabilize supply and need effectively, minimizing holding expenses while making certain stock schedule.
** Supply Analytics and Coverage **: TSCM52 teaches participants how to generate informative reports on stock motions, assessments, and turn over prices utilizing SAP ERP's effective analytics devices.

** Conveniences **: Boosted stock administration leads to lower lugging costs, decreased risk of stockouts, and much better decision-making abilities.



### 4. ** Distributor Evaluation and Efficiency Tracking **.



** Secret Emphasizes **:.



** Provider Analysis Devices **: Recognize how to use SAP ERP's evaluation metrics to evaluate distributor performance based upon high quality, distribution, and rates.
** Distributor Scorecards **: Dive into developing distributor scorecards and reports to track efficiency trends, allowing notified procurement approaches and strong supplier connections.

** Advantages **: Enhanced supplier efficiency monitoring drives continuous renovation, decreases supply chain dangers, and fosters equally valuable distributor relationships.



### 5. ** Data-Driven Decision Making in Procurement **.



** Secret Highlights **:.



** Predictive Analytics for Procurement **: Discover just how to leverage SAP ERP's anticipating analytics capabilities to forecast purchase needs and expect market changes.
** Real-Time Data Combination **: The course provides insights into integrating real-time information throughout departments, equipping purchase teams to make quick and enlightened decisions.

** Conveniences **: These analytics abilities enable purchase leaders to drive data-driven choices, maximize purchase spending plans, and remain competitive.



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** Final thought **.



The TSCM52 SAP ERP Academy Component II is a comprehensive source for professionals aiming to accomplish procurement excellence. With its focus on advanced SAP ERP capabilities, participants acquire the knowledge needed to drive operational performance, lower costs, and improve supplier relationships. By mastering these abilities, purchase teams can open new levels of effectiveness and established a standard for excellence within their companies.



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