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Exposure of airborne particulate matter (PM) with an aerodynamic diameter less than 2.5 μm (PM2.5) is epidemiologically associated with lung dysfunction and respiratory symptoms, including pulmonary fibrosis. However, whether epigenetic mechanisms are involved in PM2.5-induced pulmonary fibrosis is currently poorly understood. Herein, using a PM2.5-induced pulmonary fibrosis mouse model, we found that PM2.5 exposure leads to aberrant mRNA 5-methylcytosine (m5C) gain and loss in fibrotic lung tissues. Moreover, we showed the m5C-mediated regulatory map of gene functions in pulmonary fibrosis after PM2.5 exposure. Several genes act as m5C gain-upregulated factors, probably critical for the development of PM2.5-induced fibrosis in mouse lungs. These genes, including Lcn2, Mmp9, Chi3l1, Adipoq, Atp5j2, Atp5l, Atpif1, Ndufb6, Fgr, Slc11a1, and Tyrobp, are highly related to oxidative stress response, inflammatory responses, and immune system processes. Our study illustrates the first epitranscriptomic RNA m5C profile in PM2.5-induced pulmonary fibrosis and will be valuable in identifying biomarkers for PM2.5 exposure-related lung pathogenesis with translational potential.

We propose and experimentally demonstrate a process in which we can control the behavior of an atomic medium to switch on or off transmittance signals at multiple frequencies in ladder-type electromagnetically induced transparency (EIT) of 5S1/2−5P3/2−5D3/2 transition of Rb87 atoms. By adjusting the polarizations of the applied optical fields, the amplitudes of the transmittance spectra at multiple frequency channels can be controlled. This mechanism originates from the competition between EIT subsystems and single-photon absorption with a contribution from different transition strengths. Moreover, we also analyze the influences of the intensity and detuning of the coupling field on the transmitted signals when two lasers are perpendicular, linearly polarized lights, and observe electromagnetically induced absorption due to quantum constructive interference. Detailed theoretical analyses, including the different strengths in different transitions and Doppler broadening, agree with the experimental observations.

Background and objective The nature of pulmonary fibrosis involves inadequate repair of the epithelial cell barrier accompanied by impaired regulation of the fibroblast. Moreover, pulmonary fibrosis currently lacks an effective therapeutic drug. This study targets the protection of the epithelial cell and fibroblast to identify a novel, potentially therapeutic drug (i.e., astilbin). Methods In this study, the cytotoxicity of astilbin was firstly detected using CCK-8 . A real-time proliferation/migration analysis system was used to test the inhibitory proliferation and migration of astilbin in vitro . The expression of mesenchymal markers and the loss of epithelial cell markers were analyzed to evaluate the antifibrotic activity of astilbin on TGF-β1-treated AEC-II and L929 cells and bleomycin-treated mice. Then, in fibrosis-associated signaling pathways , the regulation of astilbin was tested using RNA sequencing and Cignal Finder 45-Pathway system. Rescue and other experiments were used to confirm this pathway regulation further. Results The data showed that astilbin inhibited proliferation and migration of cell samples. Its treatment resulted in the reduction of pathological score and collagen deposition, with a decrease in α-SMA and Snail and an increase in E-cadherin and SP-C in vivo and in vitro. The fibrosis-associated aberrant genes are some of the most notable components of the Hedgehog signaling pathway. Conclusions Astilbin ameliorates pulmonary fibrosis via blockade of Hedgehog signaling pathway and has potential therapeutic value for lung fibrosis treatment.

Hydrogen control in the case of severe accidents has been required by nuclear regulations to ensure the integrity of nuclear containment building. Therefore, getting detailed hydrogen flow and distribution is a key issue to resolve the hydrogen risk in containment and compartments. In this study, local hydrogen behavior has been investigated in a multi-subcompartments using Computational Fluid Dynamics method, concerning the local concentration in the multi-subcompartments. The multi-subcompartments containment is represented by four vessels interconnected by pipe. Hydrogen inlet pipe is located in source vessel. The analysis model is built by 3-dimensional Computational Fluid Dynamics code ANSYS-CFX in Cartesian coordinates. Computational domain is discretized in about 47559 cells, 87484 cells and 126388 cells, respectively. Taking a full consideration of the computational time and accurate, the medium mesh scheme is adopted to simulate the hydrogen transport. With standard k-ε turbulence model, the effects of the connecting pipe parameters and direction on hydrogen distribution in the multi-compartments are investigated. Local hydrogen behavior showed remarkably different in simulations with the change of the pipe parameter. Increasing the connection pipe diameter and decreasing the connection pipe length are helpful for helium flow between compartments. Compare with the vertical connection pipe, horizontal connection pipe is not conducive to the diffusion of hydrogen from source compartment to non-source compartment.

Hydrogen accumulation in the containment compartments under severe accidents would result in high concentration, which could lead to hydrogen deflagration or detonation. Therefore, getting detailed hydrogen flow and distribution is a key issue to arrange hydrogen removal equipment in the containment compartments. In this study, hydrogen flow behavior in local compartments has been investigated in two horizontal compartments. The analysis model is built by 3-dimensional CFD code in Cartesian coordinates based on the connection structure of the Advanced Pressurized Water Reactor (PWR) compartments. It consists of two cylindrical vessels, representing the Steam Generator compartment (SG) and Core Makeup Tank compartment (CMT). With standard k-ε turbulence model, the effects of the connecting pipe size and location on hydrogen concentration distribution are investigated. Results show that increasing the diameter of connection pipe (IP) which is located at 800 mm from 150 mm to 300 mm facilitates hydrogen flow between compartments. Decreasing the length of IP which is located at 800 mm from 1000 mm to 500 mm can also facilitate hydrogen flow between compartments. Lower IP is in favor of hydrogen mixing with air in non-source compartment. Higher IP is helpful for hydrogen flow to the non-source term compartment from source term compartment.

Accumulating evidence indicates that aged black garlic extract (ABGE) may prove beneficial in preventing or inhibiting oncogenesis; however, the underlying mechanisms have not been fully elucidated. The present study aimed to investigate the effects of ABGE on the proliferation and apoptosis of HT29 colon cancer cells. Our results demonstrated that ABGE inhibited HT29 cell growth via the induction of apoptosis and cell cycle arrest. We further investigated the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signal transduction pathway and the molecular mechanisms underlying the ABGE-induced inhibition of HT29 cell proliferation. We observed that ABGE may regulate the function of the PI3K/Akt pathway through upregulating PTEN and downregulating Akt and p-Akt expression, as well as suppressing its downstream target, 70-kDa ribosomal protein S6 kinase 1, at the mRNA and protein levels. In conclusion, these findings suggest that the PI3K/Akt signal transduction pathway is crucial for the development of colon cancer. ABGE inhibited the growth and induced apoptosis in HT29 cells through the inhibition of the PI3K/Akt pathway, suggesting that ABGE may be effective in the prevention and treatment of colon cancer in humans.

Being susceptible to the change of atmospheric conditions, the volume emission rate (VER) is very suitable to be used as a light source by passive remote sensing for measuring atmospheric wind and temperature. Thus, the VERs emitted from O2(0-1) and O(S1) of the nightglow at 80-120 km are studied in this paper. Based on the Naval Research Laboratory Mass Spectrometer Incoherent Scatter (NRLMSISE-00) model data and the ground-based airglow imaging interferometer (GBAII) instrument observation for a local time and place, simulated VER profiles represented by four layers are obtained for the nightglow of O2(0-1) and O(S1). The O2(0-1) nightglow model peak values at 94 km on 6 December 2013 and 8 November 2011 are 8111 photons·cm-3·s-1 and 8406 photons·cm-3·s-1, respectively; however, the O(S1) VER peak at a higher altitude of about 96 km on 18 December 2011 is only 338 photons·cm-3·s-1. The upper atmospheric VER values have been derived to transfer into the ground-based detected column intensities by our GBAII prototype. The calculated column integrated emission rates (IERs) of O2(0-1) for 0° and 45° zenith angles are 1.48×107 and 1.91×107 photons·cm-2·s-1, respectively; the calculated column IERs of O(S1) are 5.53×105 and 7.03×105 photons·cm-2·s-1, respectively. Correspondingly, the detected column IERs obtained by GBAII are 2.43×107 for O2(0-1) and 6.57×105 photons·cm-2·s-1 for O(S1).

A wide-angle Michelson interferometer based on LCoS is proposed as a novel device with no moving part for effectively measuring the upper atmospheric temperature and wind. The testing experiment gives a sequence of interferograms which can be used for evaluating the performances of this device through an image processing. The maximum phase modulations of 2.13 π and 1.58 π for 532 nm and 633 nm respectively can cover the desired detection range. The OPD variations with regard to incident angle are within 0.59 wavelengths. The instrument visibilities of 0.226–0.146 for both wavelengths have the decreasing trends with regard to the increasing incident angles. The suggestions for improving performances are also given. The results have proved its effectiveness which can satisfy the requirements for atmospheric wind measurement.

In this paper, we have proposed a novel periodic surface plasmon polariton (SPP) waveguide to realize a one-way mode converter which is based on a parity–time (PT) symmetry broken system, and it converts the fundamental TM mode to the first-order TM mode in only forward direction. Periodic gain potentials are put in place to construct the system mentioned in periodic SPP waveguide. Further, as the mode converter contains gain and loss material, light signals will be amplified when it propagates forward, and they will be attenuated toward when they propagate backward. The unidirectional mode converter has wide applications in nonlinearity induced isolation, mode insensitive element and on-chip mode locked laser.

ZnO thin films with (002) orientation have been deposited on Si(100) substrate by radio frequency (RF) magnetron sputtering technique. The influence of RF power and oxygen ratio on the the grain size-, the residual stress and optical properties was investigated by X-ray diffraction, transmission spectra and photoluminescence spectra. The results show that the ZnO film deposited with sputtering power (100W) and oxygen ratio(60%), can obtain its best c-axis orientation and crystallization and that tension stress of the film reaches the lowest, and a strong UV photoluminescence(PL) peak and a weak blue emission peak were observed.

In the research of detecting extinction ratio of polarimeter, some significant characters are discovered. One polaroid has perfect extinction ratio in the visible, but its extinction ratio becomes weak in near infrared (NIR) region, and the transmittance of a pair of vertical polaroid becomes strong in NIR region. This phenomenon has been found in several other polaroids as well. The transmittance increases greatly in NIR even if the crystal Glan-Taylor prism polarimeter with good polarization is used. The extinction ratio of the polaroid changes from 3:100 in visible to 98:100 in NIR. More experiments have shown that the weakening of extinction ratio and the enhancement of transmittance of a pair of vertical polaroid in NIR are closely associated with the intensity of incident light. When the light intensity increases, the effect becomes clearer. The transmittance exceeds the theoretical results from classical physical optics, reaching 98%. Our results provide two aspects of applications. First, because the extinction ratio of the polaroid is related to the wavelength of incident light, the polaroid can be used in definite spectral range. Second, a pair of vertical polaroid can perfectly filter the visible light, while making NIR light transmit. This research result can provide some conveniences at IR spectrum, IR photography, IR imaging and IR detection.

In order to enlarge the dynamic range of image intensifier, and CCD can work normally under the strong light (105lx), based on the generation II image intensifier, we have brought forward an novel equipment of double lens optical system including a liquid crystal panel (twisted nematic liquid crystal panel LCX023-CMT) and a photometric CCD which detects the illuminance real-time. The light intensity is controlled by liquid crystal automatically and the partial gating can be realized. The principle of auto-controlling light intensity is introduced detailedly in this paper. And the transmittance of liquid crystal has been simulated. Experimental result displays that the optical transmittance changed from 1.28% to 25.60% with the gray levels from 0 to 250. The high linearity relation of transmittance to gray levels is obtained when the gray levels change from 90 to 220. The feasibility of partial light intensity auto-controlled by liquid crystal has been further proved by the two obvious contrast pictures that one is photographed with the liquid crystal panel and another without.

A liquid crystal panel module coupled in the image intensifier which has been coupled the magnetic mirror has been proposed. The normal imaging under strong light and the part gating of light intensity control can be achieved by changing the transmittance of these pixel points which is changed by the voltage imposed on pixel points. Influence of the response time and transmittance of the liquid crystal to the entire system have been researched, that liquid crystal can achieve part gating function has been confirmed through experiments. Liquid crystal display module (LCP)'s response time is 22ms by using the 650nm, 4mw SZ-04 laser and the transmittance of LCP ranges from 1.28 to 25.60%.It has been proved that the liquid crystal selected in this article fit for the entire LCP. Photography effect graphs achieved by part gating of light intensity have been got.

In order to enhance the civil digital photography system's latitude, a kind of new structure is put forward which is made the liquid crystal plate coupled to CCD/CMOS (Charge Coupled Device/Complementary Metal Oxide Semiconductor) sensitive chip in this paper. We call this structure chip is LCCCD (liquid crystal CCD). This new system's key is proximity coupled a high precision HTPS (Low Temperature Poly-Silicon) liquid crystal plate on the foundation of current CCD/CMOS chip; each pixel on the liquid crystal plate corresponds with the pixel on CCD/CMOS one by one. They compose the new sensitive photosensitive chip that can control the each pixel's ratio of photoelectric conversion by changing each liquid crystal unit's transmittance. This paper expounds this system's structure as well as various modules' cooperation mode and the process of achieving the aim. Through analysis original image by common camera and the same image by LCCCD camera, these results are obtained: the image is changed directly on the physical level by the new system is much better than produces by post treatment, moreover the system can rectify images by 10bit precision, and the imaging latitude has been enhanced more than 5EV (EV is exposure level).

Based on the electro-optical properties of liquid crystal, we have designed a novel partial gating detector. Liquid crystal can be taken to change its own transmission according to the light intensity outside. Every single pixel of the image is real-time modulated by liquid crystal, thus the strong light is weakened and low light goes through the detector normally .The purpose of partial-gating strong light (>10 5 lx) can be achieved by this detector. The modulation transfer function (MTF) equations of the main optical sub-systems are calculated in this paper, they are liquid crystal panels, linear fiber panel and CCD array detector. According to the relevant size, the MTF value of this system is fitted out. The result is MTF= 0.518 at Nyquist frequency.

In order to enhance the dynamic range of digital imaging system, we have brought forward processing image by the Cyclone II chip and controlling HTPS's high-density liquid crystal unit. The system in this paper proposed a kind of low cost solution, the luminous intensity entering each pixel of CCD can be adjusted directly accurately. Meanwhile, the attenuation luminance coefficients set by system algorithm and precision parameters can be adjusted artificially on the physical level to satisfy different needs. It is proving that the function of partial gating image is realized by the image processing experiment in which the details of the final image are more obvious and clear than the original. Then the system latitude problem is solved fundamentally. The image of partial gating is obtained through the experiment, and then the anticipated goal has achieved successfully.

The spatially modulated polarization interference imaging spectroscopy (SMPIIS) is based on the polarization interferometer.The core of the polarization interferometer is the Savart polariscope. When light passing through polarizer,the natural light becomes linearly polarized in the direction of the polarization orientation of a linear polarizer. The linearly polarized ray is split into two polarized components by a Savart polariscope. After going through the analyzer,the two rays get linearly polarized in the polarized orientation of the analyzer and are focused by the imaging lens to form the interferogram and target image. From analyzing the mechanism of formation the interferogram and target image,we find the discrete between ordinary ray (o-ray) and extraordinary ray (e-ray) greatly influence the intensities and the results of the interferogram and target image. The wave vector of e-ray is obtained by the extension of Snell's law in the Savart polariscope. According to the relation between the wave vector of e-ray and e-ray,the direction of e-ray is solved. After the directions of o-ray and e-ray are given, the formula of the discrete between o-ray and e-ray can be got by calculating.

A novel imaging system has been designed in order to enhance the dynamic range of image intensifier, and make it image normally at high illumination based on the principle of liquid crystal for partial gating detection. This system is made up of lens, HTPS TFT-LCD (proximity to the image intensifier), photometric CCD, main CCD and control circuit. Under the high illumination environment, main control chip FPGA extract the output signals of photometric CCD as feedback signals, and get the environmental absolute intensity after some algorithm processing. Then the chip renews the color signals' value of YUV formats. Lastly, the HTPS TFT-LCD drive board receives the processed color signal, controls the transmittance of every pixel on the HTPS TFT-LCD. So the ultra bright partial of image can be weakened. Under the normal or weak light condition, LCD will be moved away by mechanical devices because its transmittance is about 30%. This paper gives the control principle and structure of the system and puts forward the CCD' photometric principle.

In order to improve the detectability of low-light imaging CCD (charge coupled devices), we have brought forward a magnetic mirror device to apply to microchannel electron vase plate ((MEVP)) of low-light imaging system at room temperature. After introduced the principle of restricted electron in magnetic mirror field to accumulate enough time for low-light CCD imaging, magnetic intensity has been calculated discretionary position in the mirror, the formula of electron's velocity direction has been given through the throat of magnetic mirror in this paper. The educed electron's angle distribution between velocity direction and magnetic mirror axis has been simulated at 7-10 degree. This answers for the design needs of microchannel vase plate now. The electron's loop speckle imaging has been obtained by experiment; the result is same as theoretical value. It is proved that if the electrons educed by the magnetic mirror field at the same cone angle and approximate speed, the gain of microchannel plate will be more stable, so that it is favorable to reduce the noise of photoelectronic imaging.

The modified super-wide-angle Sagnac interferometer (SASI) is designed for upper atmospheric wind measurement. The formula of SASI's optical path difference (OPD) is derived, in which the OPD versus the sine series of incidence angle in order of 4. The SASI's fully compensations of super-wide-angle, achromatic, thermal, wavelength-independent thermal conditions have been investigated. The SASI configuration for the above compensations was successfully setup by selecting correct glasses from the 113 kinds of glasses. The optimized SASI is made of ZBaF17 and QF14 glasses, and the arm lengths are accurately configured. Based on the configuration of glass types and arm lengths of SASI, it shows that SASI achromatic condition is satisfied synchronously for three aurora's emission lines, which are 557.7nm, 630.0nm and 732.0nm respectively. The relative error of SASI's lengths does not exceed 1%. The full field of view (FOV) of the SASI is 6°. It is about 5° in full angle from SASI optical axis to CCD farthest corner. The first order fringe occupies about 67% of the CCD area.

In order to obtain information both of aurora and airglow in one image by the same detector, a PLCI based on liquid crystal plate LCP and super second-generation image intensifier SSGII is proposed in this research. The detection thresholds of the CCD for aurora and airglow are calculated. For the detectable illumination range of 104–10−2 lx, the corresponding electron count is 1.57×105−0.2 for every pixel of CCD. The structure and work principle of the PLCI are described. An LC is introduced in the front of CCD to decrease the intensities of aurora in overexposure areas by means of controlling transmittances pixel by pixel, while an image intensifier is set between the LC and CCD to increase the intensity of the weak airglow. The modulation transfer function MTF of this system is calculated as 0.391 at a Nyquist frequency of 15 lp/mm. The curve of transmittance with regard to gray level for the LC is obtained by calibration experiment. Based on the design principle, the prototype is made and used to take photos of objects under strong light greater than 2×105 lx. The clear details of “西安理工大学XauT” presented in the image indicate that the PLCI can greatly improve the imaging quality. The theoretical calculations and experiment results prove that this device can extend the dynamic range and it provides a more effective method for upper atmospheric wind measurement.

A wide-angle Michelson interferometer with large air gap is proposed to effectively reduce the size of the glass arms and constraint on material. It provides a novel and practical instrument for ground based wind measurement of the upper atmosphere. The field widening conditions for the large air gap are calculated in theory. For the five spectral lines of 557.7 nm, 630.0 nm, 732.0 nm, 834.6 nm, and 865.7 nm, the optimal results under ideal condition are obtained with air gaps of 1.0 cm, 1.5 cm, and 2.0 cm, respectively. With the fixed optical path difference (OPD) of 7.495 cm, three pairs of glass arms are optimized. The pair with length of 1.5 cm for air gap, 5.765 cm for H-ZF12, and 2.956 cm for H-ZLaF54, has better effect of field widening than the other two pairs and its OPD variation is only within 0.30 wavelengths at incident angle of 3°. For developing a more practical wide-angle Michelson interferometer, the H-K9L glass with size of 4.445 cm is employed as the arm material of solid interferometer. The experiment for field of view of 3° is designed and the data processing and analysis for 60 images show the agreement between experimental results and theoretical simulation. The OPD variations are only within 0.27 wavelengths for image edge. The feasibility and practicality of the wide-angle Michelson interferometer with large air gap is proved by means of theory and experiment.

A partially light-controlled imaging system is proposed as a novel device. It is used to improve the imaging quality at the illumination of 1.979 x 10(5)lx by means of mitigating image contrast. It consists of a High Temperature Poly-Silicon Thin Film Transistor-Liquid Crystal Display (HTPS TFT-LCD), which is set between the lens and CCD and is coupled with CCD by the optical fiber taper. The transmittance of pixelated LCD can be controlled by Field-Programmable Gate Array to realize the partially light-controlled and thus dynamic range of the imaging system can be extended. Samples of indoor objects and outdoor license plate are photographed by the prototype imaging system under strong light. The imaging results of this novel system are satisfactory with better restored details, compared with the photos taken by normal CCD camera (WAT-231S2) which uses aperture and shutter to control the overall light intensity.