Bidirectional associations among gallstone disease, non-alcoholic fatty liver disease, kidney stone disease.

Background: A body of evidence has suggested bidirectional relationships among gallstone disease (GSD), non-alcoholic fatty liver disease (NAFLD), and kidney stone disease (KSD). However, the results are inconsistent, and studies on this topic in China are relatively few. Our goal is to explore the bidirectional associations among these three diseases through a multicenter study, systematic review, and meta-analysis.

Light-induced symmetry breaking for enhancing second-harmonic generation from an ultrathin plasmonic nanocavity.

Efficient frequency up-conversion of coherent light at the nanoscale is highly demanded for a variety of modern photonic applications, but it remains challenging in nanophotonics. Surface second-order nonlinearity of noble metals can be significantly boosted up by plasmon-induced field enhancement, however the related far-field second-harmonic generation (SHG) may also be quenched in highly symmetric plasmonic nanostructures despite huge near-field amplification. Here, we demonstrate that the SHG from a single gold nanosphere is significantly enhanced when tightly coupled to a metal film, even in the absence of a plasmon resonance at the SH frequency.

Crystalline Silicon White Light Sources Driven by Optical Resonances.

Silicon (Si) is generally considered as a poor photon emitter, and various scenarios have been proposed to improve the photon emission efficiency of Si. Here, we report the observation of a burst of the hot electron luminescence from Si nanoparticles with diameters of 150-250 nm, which is triggered by the exponential increase of the carrier density at high temperatures. We show that the stable white light emission above the threshold can be realized by resonantly exciting either the mirror-image-induced magnetic dipole resonance of a Si nanoparticle placed on a thin silver film or the surface lattice resonance of a regular array of Si nanopillars with femtosecond laser pulses of only a few picojoules, where significant enhancements in two- and three-photon-induced absorption can be achieved.

Mapping the Magnetic Field Intensity of Light with the Nonlinear Optical Emission of a Silicon Nanoparticle.

To detect the magnetic component of arbitrary unknown optical fields, a candidate probe must meet a list of demanding requirements, including a spatially isotropic magnetic response, suppressed electric effect, and wide operating bandwidth. Here, we show that a silicon nanoparticle satisfies all these requirements, and its optical magnetism driven multiphoton luminescence enables direct mapping of the magnetic field intensity distribution of a tightly focused femtosecond laser beam with varied polarization orientation and spatially overlapped electric and magnetic components. Our work establishes a powerful nonlinear optics paradigm for probing unknown optical magnetic fields of arbitrary electromagnetic structures, which is not only essential for realizing subwavelength-scale optical magnetometry but also facilitates nanophotonic research in the magnetic light-matter interaction regime.

Metal-Substrate-Mediated Plasmon Hybridization in a Nanoparticle Dimer for Photoluminescence Line-Width Shrinking and Intensity Enhancement.

Metal-film-coupled nanoparticles with subnanometer particle-film gaps possess an ultrasmall mode volume, responsible for a variety of intriguing phenomena in plasmonic nanophotonics. Due to the large radiative loss associated with dipolar coupling, however, the plasmonic-film-coupled nanocavities usually feature a low-quality factor, setting an ultimate limit of the increased light-matter interaction strength. Here, we demonstrate a plasmonic nanocavity composed of a metal-film-coupled nanoparticle dimer, exhibiting a significantly improved quality factor.

Pronounced Fano Resonance in Single Gold Split Nanodisks with 15 nm Split Gaps for Intensive Second Harmonic Generation.

Single metallic nanostructures supporting strong Fano resonances allow more compact nanophotonics integration and easier geometrical control in practical applications such as enhanced spectroscopy and sensing. In this work, we designed a class of plasmonic split nanodisks that show pronounced Fano resonance comparable to that observed in widely studied plasmonic oligomer clusters. Using our recently developed "sketch and peel" electron-beam lithography, split nanodisks with varied diameter and split length were fabricated over a large area with high uniformity.

Hybrid plasmonic gap modes in metal film-coupled dimers and their physical origins revealed by polarization resolved dark field spectroscopy.

Plasmonic gap modes sustained by metal film-coupled nanostructures have recently attracted extensive research attention due to flexible control over their spectral response and significantly enhanced field intensities at the particle-film junction. In this work, by adopting an improved dark field spectroscopy methodology - polarization resolved spectral decomposition and colour decoding - we are able to "visualize" and distinguish unambiguously the spectral and far field radiation properties of the complex plasmonic gap modes in metal film-coupled nanosphere monomers and dimers. Together with full-wave numerical simulation results, it is found that while the monomer-film system supports two hybridized dipole-like plasmon modes having different oscillating orientations and resonance strengths, the scattering spectrum of the dimer-film system features two additional peaks, one strong yet narrow resonant mode corresponding to a bonding dipolar moment and one hybridized higher order resonant mode, both polarized along the dimer axis.

Polarization-Independent Multiple Fano Resonances in Plasmonic Nonamers for Multimode-Matching Enhanced Multiband Second-Harmonic Generation.

Plasmonic oligomers composed of metallic nanoparticles are one class of the most promising platforms for generating Fano resonances with unprecedented optical properties for enhancing various linear and nonlinear optical processes. For efficient generation of second-harmonic emissions at multiple wavelength bands, it is critical to design a plasmonic oligomer concurrently having multiple Fano resonances spectrally matching the fundamental excitation wavelengths and multiple plasmon resonance modes coinciding with the harmonic wavelengths. Thus far, the realization of such a plasmonic oligomer remains a challenge.

Efficient three-photon luminescence with strong polarization dependence from a scintillating silicate glass co-doped with Gd3+ and Tb3+.

Efficient three-photon luminescence (3PL) from a scintillating silicate glass co-doped with Gd(3+) and Tb(3+) was generated by using a focused femtosecond laser beam at 800 nm. Four emission bands centered at 496, 541, 583, and 620 nm were identified as the electronic transitions between the energy levels of Tb(3+) followed by three-photon absorption (3PA) in Gd(3+) and Tb(3+) and the resonant energy transfer from Gd(3+) to Tb(3+). More interestingly, a strong polarization dependence of the 3PL was observed and it is ascribed to the polarization dependent 3PA in Gd(3+) and Tb(3+) and/or the angular distribution of photogenerated electrons in the glass.

Size dependent competition between second harmonic generation and two-photon luminescence observed in gold nanoparticles.

We investigate systematically the competition between the second harmonic generation (SHG) and two-photon-induced luminescence (TPL) that are simultaneously present in Au nanoparticles excited by using a femtosecond (fs) laser. For a large-sized (length ~ 800 nm, diameter ~ 200 nm) Au nanorod, the SHG appears to be much stronger than the TPL. However, the situation is completely reversed when the Au nanorod is fragmented into many Au nanoparticles by the fs laser.

Role of interfering optical fields in the trapping and melting of gold nanorods and related clusters.

We investigate the simultaneous trapping and melting of a large number of gold (Au) nanorods by using a single focused laser beam at 800 nm which is in resonance with the longitudinal surface plasmon resonance of Au nanorods. The trapping and melting processes were monitored by the two-photon luminescence of Au nanorods. A multi-ring-shaped pattern was observed in the steady state of the trapping process.

Assembling of three-dimensional crystals by optical depletion force induced by a single focused laser beam.

We proposed a method to assemble microspheres into a three-dimensional crystal by utilizing the giant nonequilibrium depletion force produced by nanoparticles. Such assembling was demonstrated in a colloid formed by suitably mixing silica microspheres and magnetic nanoparticles. The giant nonequilibrium depletion force was generated by quickly driving magnetic nanoparticles out of the focusing region of a laser light through both optical force and thermophoresis.

Fiber magnetic-field sensor based on nanoparticle magnetic fluid and Fresnel reflection.

A simple fiber sensor for magnetic field measurement based on nanoparticle Fe(3)O(4) magnetic fluid and relative Fresnel reflection is presented. The sensor includes only a light source, three couplers, two photodetectors, and two fiber sensing ends. Magnetic fields at different concentrations of magnetic fluid are measured.

Sensory denervation reduces visceral hypersensitivity in adult rats exposed to chronic unpredictable stress: evidences of neurogenic inflammation.

The purpose of this study is to provide evidence of neurogenic inflammation in chronic unpredictable stressed rats with the changes of visceral sensitivity, number of mast cells, and close proximity among mast cell-nerve-blood vessels. We found that (1) capsaicin denervation blocked stress-induced increase of visceral sensitivity, while doxantrazole presented a partial blocking; (2) capsaicin denervation blocked stress-induced enhancement of the proximity of mast cell-nerve fiber-blood vessels and blood vessel damage, while doxantrazole showed no effects on these; (3) doxantrazole blocked stress-induced increases of the MPO activity, the number and the degranulation of mast cells in the colon; (4) sensory denervation and doxantrazole had no effects on stress-induced behavioral inhibition. These results suggest that capsaicin-sensitive sensory fibers play a key role in stress-induced visceral hypersensitivity and the ultrastructural changes, mast cells play an important role in the generation of stress-induced colon inflammation.

Evidence of human papilloma virus infection and its epidemiology in esophageal squamous cell carcinoma.

Aim: To look for the evidence of human papilloma virus (HPV) infection in esophageal squamous cell carcinomas (ESCC) and to investigate the potential role and epidemiology of HPV infection in the pathogenesis of esophageal carcinomas in Henan emigrants.

Methods: Papilloma virus(PV) and HPV were determined by Ultrasensive S-P immunohistochemistry (IHC) and in situ hybridization (ISH)in esophageal carcinoma tissues (82 cases) and the normal mucosa (40 cases).

Results: IHC revealed that the positive rate of PV was 75.