LTB4 Promotes Acute Lung Injury via Upregulating the PLCε-1/TLR4/NF-κB Pathway in One-Lung Ventilation.

BACKGROUND: Mechanical ventilation (MV) can provoke acute lung injury (ALI) by increasing inflammation activation and disrupting the barrier in lung tissues even causing death. However, the inflammation-related molecules and pathways in MV-induced ALI remain largely unknown. Hence, the purposes of this study are to examine the role and mechanism of a novel inflammation-related molecule, leukotriene B4 (LTB4), in ALI. METHODS: The functions of LTB4 in one-lung ventilation (OLV) model were detected by the loss-of-function experiments. H&E staining was used to examine the pathologic changes of lung tissues. Functionally, PLCε-1 knockdown and Toll-like receptor 4 (TLR4)/NF-κB pathway inhibitor were used to detect the regulatory effects of LTB4 on the phospholipase Cε (PLCε-1)/TLR4/nuclear factor-kappa B (NF-κB) pathway. The levels of genes and proteins were determined by RT-qPCR and western blotting assay. The levels of inflammation cytokines and chemokines were measured by ELISA. RESULTS: Here, we found LTA4H, leukotriene B (4) receptor 1 (BLT1), LTB4, and PLCε-1 upregulated in OLV rats and associated with inflammatory activation and lung permeability changes of lung tissues. Inhibition of LTB4 alleviated the OLV-induced ALI by inhibiting inflammatory activation and lung permeability changes of lung tissues. For mechanism analyses, LTB4 promoted OLV-induced ALI by activating the PLCε-1/TLR4/NF-κB pathway. CONCLUSION: LTB4 induced ALI in OLV rats by activating the PLCε-1/TLR4/NF-κB pathway. Our findings might supply a new potential therapeutic for OLV-induced ALI.

Rapid and precise compensation of scale factor in a fiber-optic gyroscope with a twin-peaks source.

In this Letter, two gyro outputs containing identical rotation rates are produced by a twin-peaks light source with peak wavelengths of 1530 nm and 1560 nm. We demonstrate that the two outputs' ratio κ can compensate for the temperature-induced scale factor drift in an interferometric fiber-optic gyroscope (IFOG). When the temperature ranged from -10∘C to 50°C, the scale factor drift after compensation was about 30 times less than that before compensation, and the minimum drift was ±7.7ppm at the rotation rate of 100°/s.

Open-loop fiber-optic gyroscope with a double sensitivity employing a polarization splitter and Faraday rotator mirror.

In this Letter, a novel open-loop fiber-optic gyroscope configuration with a double sensitivity is proposed. By employing a polarization-maintaining Faraday rotator mirror and a polarization beamsplitter/combiner, light waves propagate twice along the same fiber coil in two orthonormal polarization directions. The reciprocity of the configuration has been verified in theory. The Allan variance analysis of the gyro prototype exhibits 0.03°/h bias stability over 5.5 h in the laboratory environment.

Novel optical super-resolution pattern with upright edges diffracted by a tiny thin aperture.

In the past decade numerous efforts have been concentrated to achieve optical imaging resolution beyond the diffraction limit. In this letter a thin microcavity theory of near-field optics is proposed by using the power flow theorem firstly. According to this theory, the near-field optical diffraction from a tiny aperture whose diameter is less than one-tenth incident wavelength embedded in a thin conducting film is investigated by considering this tiny aperture as a thin nanocavity. It is very surprising that there exists a kind of novel super-resolution diffraction patterns showing resolution better than λ/80 (λ is the incident wavelength), which is revealed for the first time to our knowledge in this letter. The mechanism that has allowed the imaging with this kind of super-resolution patterns is due to the interaction between the incident wave and the thin nanocavity with a complex wavenumber. More precisely, these super-resolution patterns with discontinuous upright peaks are formed by one or three items of the integration series about the cylindrical waves according to our simulation results. This novel optical super-resolution with upright edges by using the thin microcavity theory presented in the study could have potential applications in the future semiconductor lithography process, nano-size laser-drilling technology, microscopy, optical storage, optical switch, and optical information processing.

Fiber gyroscope with a double sensitivity employing a polarization splitter.

An effective method for enhancing the sensitivity of interferometric fiber-optic gyroscope (IFOG) is presented. Light waves propagate twice along the same sensing coil made of polarization-maintaining fiber in different polarization states by inducing a fiber polarization splitter/combining in the IFOG. Preliminary performance data of a gyro prototype exhibits 0.006°/h bias stability.

Multifrequency erbium-doped fiber laser operating at room temperature.

A method to realize room-temperature operation of a multifrequency Er-doped fiber laser with low-frequency shift feedback placed within a linear laser cavity is theoretically proposed and experimentally demonstrated. Simultaneous multiwavelength lasing with 0.5 nm wavelength spacing is experimentally demonstrated by applying a sinusoidal signal of 10 kHz to a fiber phase modulator inserted within the linear cavity to prevent single wavelength steady-state oscillation. In the linear cavity, an all-polarization-maintaining fiber Sagnac loop is used as a periodic filter, and a single-mode fiber loop with a polarization controller is used as a partial reflector and also as an output port.

Room-temperature multiwavelength erbium-doped fiber ring laser employing sinusoidal phase-modulation feedback.

An effective method for achieving a room-temperature multiwavelength erbium-doped fiber ring laser is presented. Simultaneous multiwavelength lasing with 0.5-nm intervals is achieved both experimentally and theoretically by addition of sinusoidal phase modulation in the ring cavity to prevent single-wavelength oscillation.