2023
2023
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Record 517 of
Title:Solar Polar-orbit Observatory
Author(s):Deng, Yuanyong(1,9); Zhou, Guiping(1,9); Dai, Shuwu(3); Wang, Ying(3); Feng, Xueshang(4); He, Jiansen(5); Jiang, Jie(6); Tian, Hui(5); Yang, Shangbin(1,9); Hou, Junfeng(1,9); Yan, Yihua(4,9); Gan, Weiqun(7); Bai, Xianyong(1,9); Li, Leping(1,9); Xia, Lidong(8); Li, Hui(7); Su, Yang(7); Xiong, Ming(4); Zhang, Yechi(3); Zhu, Chenglin(3); Lin, Jiaben(1,9); Zhang, Haiying(10); Chen, Bo(11); He, Lingping(11); Feng, Li(7); Zhang, Hongxin(11); Sun, Mingzhe(8); Zhang, Aibing(4); Chen, Linjie(4,9); Tan, Baolin(1,9); Zhang, Zhe(7); Yang, Jianfeng(12); Yang, Mengfei(2); Wang, Jingxiu(1,9)Source: Kexue Tongbao/Chinese Science Bulletin Volume: 68 Issue: 4 Article Number: null DOI: 10.1360/TB-2022-0674 Published: 2023Abstract:Solar magnetic fields and related solar magnetic activities dominate the heliospheric environments from the near-Earth space, to the interplanetary space, and up to the interstellar boundary. The polar magnetic fields of the Sun and its dynamic processes are especially vital in the aspects of manifesting the internal dynamo of the Sun, and shaping magnetic fields in the heliosphere. But so far, almost all the solar satellites have been limited in the vicinity of the ecliptic plane. Due to the serious projection effect, the polar regions remain as the least-known mysterious territory of the Sun. The spacecraft of "Solar Polar-orbit Observatory (SPO)" has been designed to directly image the solar polar regions in an unprecedented way by traveling in a large solar inclination angle (≥ 80°) and a small ellipticity. Based on multi-band remote-sensing and in-situ measurements, the SPO will make breakthrough on the following top-level scientific objectives: (1) Provide decisive observations for solving the problem of the century—How the solar magnetic activity cycle originates that shapes the living environment of human beings; (2) provide direct observational supports for unveiling the origin, mechanism, and effect of the "primitive" high-speed solar wind that connects the Sun and celestial bodies in the solar system; (3) provide the necessary, complete, and self-consistent initial and boundary conditions for creating a data-driven global heliospheric numerical model that serves as the foundation for space weather prediction. To achieve these scientific objectives, the SPO will be equipped with six remote-sensing instruments and one in-situ instrument package. The remote-sensing instruments are Magnetic and Helioseismic Imager (MHI; FOV: 34′ (full disk)/17′ (high resolution); pixel resolution: 1″/0.5″; sensitivity: 10 G (longitudinal), 200 G (transverse); cadence: 15 min; sensitivity of Doppler velocity: 30 m/s; Cadence: 1 min), Extreme Ultraviolet Solar Telescope (EUST; FOV: 51′; spatial resolution: 3.5″; imaging band: 19.3, 17.1, 13.1 and 30.4 nm; cadence: 1 min), Visible-light Coronagraph (VISCO; FOV: 0.69°–2.67° annular; pixel resolution: 4.8″; wave band: 700±40 nm; cadence: 2 min), Very Large Angle Coronagraph (VLACOR; FOV: 2.67°–24° annular; pixel resolution: 45″; wave band: 600–750 nm; cadence: 10 min (white light), 60 min (polarization)), X-ray Imaging Telescope (XIT; FOV: 48′; angular resolution: 10″; energy range: Energy spectrum 0.5–10 keV; spectral resolution: 1 keV@6 keV; time resolution: 5 s (common), 1 s (burst)), and Low Frequency Radio Spectrometer (LFRS; frequency range: 10 kHz–2.0 MHz and 1.0–50 MHz; spectral resolution: ≤5 kHz@2.0 MHz and ≤0.1 MHz@50 MHz; time resolution: 1 s; dynamic range: >72 dB). The in-situ instrument package includes Solar Wind Ion Analyzer (SWIA), Solar Energetic Particles Analyzer (SEPA), and Magnetometer (MAG). ? 2023 Chinese Academy of Sciences. All rights reserved.Accession Number: 20230813608181 -
Record 518 of
Title:Machine learning reveals the effects of drivers on PM2.5 and CO2 based on ensemble source apportionment method
Author(s):Xu, Han(1,2); Ge, Yi(3); Zhang, Chun(3); Wang, Zhenyu(1,2); Xu, Bo(1,2); Zhao, Huan(1,2); Huang, Junbo(1,2); Wang, Gen(4); Liu, Jinxing(5,6); Feng, Yinchang(1,2); Shi, Guoliang(1,2)Source: Atmospheric Research Volume: 295 Issue: null Article Number: 107019 DOI: 10.1016/j.atmosres.2023.107019 Published: November 2023Abstract:Air pollution and climate change are currently common global concern issues. Understanding the main pollution sources of fine particulate matter (PM2.5) and carbon dioxide (CO2), and the drivers that accelerate their concentrations can provide novel insights into the co-benefits of air-quality improvement and climate change mitigation. Hence, in this study, we conducted source apportionment of PM2.5 and CO2, and obtained impacts of common sources on PM2.5-CO2 using an ensemble source apportionment method. Then, machine learning (ML) methods were utilized to study the effects of different drivers (including main pollution sources and meteorological factors) on PM2.5 and CO2. The results demonstrate that coal combustion (40%), vehicle exhaust (37%), and industrial emissions (23%) were the main common sources of PM2.5 and CO2. Controlling the combustion of fossil fuels and long-term vehicle electrification still hold significant importance for reducing pollutions and carbon emissions. The results of data-driven ML models show that temperature had the highest effect among meteorological factors, reflecting the seasonal changes of CO2 and PM2.5. The study provides a feasible framework for exploring co-benefits of clean air policies on greenhouse gas emissions based on online observation dataset. ? 2023 Elsevier B.V.Accession Number: 20233814751946 -
Record 519 of
Title:Orally administration of cerium oxide nanozyme for computed tomography imaging and anti-inflammatory/anti-fibrotic therapy of inflammatory bowel disease
Author(s):Cao, Yameng(1,2,5); Cheng, Kai(3); Yang, Mei(1,2,5); Deng, Zhichao(1,2,5); Ma, Yana(1,2,5); Yan, Xiangji(1,2,5); Zhang, Yuanyuan(1,2,5); Jia, Zhenzhen(1,2,5); Wang, Jun(4); Tu, Kangsheng(1); Liang, Jie(6); Zhang, Mingzhen(1,2,5)Source: Journal of Nanobiotechnology Volume: 21 Issue: 1 Article Number: 21 DOI: 10.1186/s12951-023-01770-0 Published: December 2023Abstract:Background: Inflammatory bowel disease (IBD) is a chronic nonspecific disease with unknown etiology. Currently, the anti-inflammatory therapeutic approaches have achieved a certain extent of effects in terms of inflammation alleviation. Still, the final pathological outcome of intestinal fibrosis has not been effectively improved yet. Results: In this study, dextran-coated cerium oxide (D-CeO2) nanozyme with superoxide dismutase (SOD) and catalase (CAT) activities was synthesized by chemical precipitation. Our results showed that D-CeO2 could efficiently scavenge reactive oxide species (ROS) as well as downregulate the pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and iNOS) to protect cells from H2O2-induced oxidative damage. Moreover, D-CeO2 could suppress the expression of fibrosis-related gene levels, such as α-SMA, and Collagen 1/3, demonstrating the anti-fibrotic effect. In both TBNS- and DSS-induced colitis models, oral administration of D-CeO2 in chitosan/alginate hydrogel alleviated intestinal inflammation, reduced colonic damage by scavenging ROS, and decreased inflammatory factor levels. Notably, our findings also suggested that D-CeO2 reduced fibrosis-related cytokine levels, predicting a contribution to alleviating colonic fibrosis. Meanwhile, D-CeO2 could also be employed as a CT contrast agent for noninvasive gastrointestinal tract (GIT) imaging. Conclusion: We introduced cerium oxide nanozyme as a novel therapeutic approach with computed tomography (CT)-guided anti-inflammatory and anti-fibrotic therapy for the management of IBD. Collectively, without appreciable systemic toxicity, D-CeO2 held the promise of integrated applications for diagnosis and therapy, pioneering the exploration of nanozymes with ROS scavenging capacity in the anti-fibrotic treatment of IBD. ? 2023, The Author(s).Accession Number: 20230413427655 -
Record 520 of
Title:Revolutionizing wound healing: Ultrashort pulse electric fields in seconds for highly aligned extracellular matrix and efficient cell migration
Author(s):Xiang, Xiao-Wei(1); Liu, Hao-Tian(1); Liu, Wei(2); Yan, Ze-Yao(3); Zeng, Yu-Lian(4); Wang, Ya-Jun(2); Liu, Jing(1); Chen, Yu-Chen(2); Yu, Sai-Xi(2); Zhu, Cai-Hui(3); Tao, Xiao-Nan(3); Wang, Chen(2); Wu, Jin-Tao(4); Du, Yang(2); Xu, Xin-Xin(2); Gao, Hai(2); Jiu, Yaming(5); Ma, Jiong(6); Qiu, Jian(3); Chang, Lingqian(7); Jing, Guangyin(8); Liu, Ke-Fu(3); Liu, Yan-Jun(2)Source: Chemical Engineering Journal Volume: 471 Issue: null Article Number: 144267 DOI: 10.1016/j.cej.2023.144267 Published: September 1, 2023Abstract:Wound healing is a complicated process for maintaining skin integrity after injury, for which electrical stimulations (ES) have been attributed to promote wound healing by facilitating cell migration. Reducing the duration of the stimulation treatment from hours to minutes to promote efficient wound healing while avoiding cell damage poses a considerable challenge. Here, a promising technology of ultrashort pulse electric field (PEF), microsecond PEF at higher voltage, is proposed and realized to promote wound healing under a much short time (seconds) for the total treatment. We revealed that microsecond PEF regulated actin cytoskeleton reorganization and focal adhesion turnover, promoting fibroblasts migration in 2D cell cultures under the pulse stimulation. This accelerated fibroblast migration was accompanied by the mutual promotion with extracellular matrix (ECM) alignment in 3D microenvironments, which cooperatively benefit the eventual wound healing. These findings were further corroborated by the significant 2.5-fold enhancement observed in the healing of skin wounds in the classical mouse model by day 6 after electrical stimulation. Additionally, we coined an actin- and collagen-dependent mechanism of microsecond PEF-mediated wound healing. The quantitative mechanism proposed here for our novel microsecond pulse electric filed (μsPEF) methodology orients the new practical electric treatment toward a wide range of biomedical applications, such as wound healing, regenerative medicine and tissue engineering. ? 2023 Elsevier B.V.Accession Number: 20232914417734 -
Record 521 of
Title:Ultrafast two-dimensional x-ray imager with temporal fiducial pulses for laser-produced plasmas
Author(s):Liu, Zheng-Dong(1,2); Zhong, Jia-Yong(1,2,6); Yuan, Xiao-Hui(5,6); Zhang, Ya-Peng(1,2); Yao, Jia-Wen(1,2); Ma, Zuo-Lin(1,2); Xu, Xiang-Yan(3); Xue, Yan-Hua(3); Zhang, Zhe(4,6,11); Yuan, Da-Wei(2,7); Zhang, Min-Rui(3); Li, Bing-Jun(9); Gu, Hao-Chen(4,12); Dai, Yu(4,12); Zhang, Cheng-Long(4,8); Dong, Yu-Feng(4,12); Zhou, Peng(5,6); Ma, Xin-Jie(9); Ma, Yun-Feng(9); Bai, Xue-Jie(9); Liu, Gao-Yang(10); Tian, Jin-Shou(3); Zhao, Gang(7); Zhang, Jie(4,5,6)Source: Chinese Physics B Volume: 32 Issue: 11 Article Number: 110702 DOI: 10.1088/1674-1056/ace766 Published: November 1, 2023Abstract:It is challenging to make an ultrafast diagnosis of the temporal evolution of small and short-lived plasma in two dimensions. To overcome this difficulty, we have developed a well-timed diagnostic utilizing an x-ray streak camera equipped with a row of multi-pinhole arrays. By processing multiple sets of one-dimensional streaked image data acquired from various pinholes, we are capable of reconstructing high-resolution two-dimensional images with a temporal resolution of 38 ps and a spatial resolution of 18 μm. The temporal fiducial pulses accessed from external sources can advance the precise timing and accurately determine the arrival time of the laser. Moreover, it can correct the nonlinear sweeping speed of the streak camera. The effectiveness of this diagnostic has been successfully verified at the Shenguang-II laser facility, providing an indispensable tool for observing complex physical phenomena, such as the implosion process of laser-fusion experiments. ? 2023 Chinese Physical Society and IOP Publishing Ltd.Accession Number: 20234715085221 -
Record 522 of
Title:Detecting the Background-Similar Objects in Complex Transportation Scenes
Author(s):Sun, Bangyong(1); Ma, Ming(1); Yuan, Nianzeng(2); Li, Junhuai(2); Yu, Tao(3)Source: IEEE Transactions on Intelligent Transportation Systems Volume: null Issue: null Article Number: null DOI: 10.1109/TITS.2023.3268378 Published: 2023Abstract:With the development of intelligent transportation systems, most human objects can be accurately detected in normal road scenes. However, the detection accuracy usually decreases sharply when the pedestrians are merged into the background with very similar colors or textures. In this paper, a camouflaged object detection method is proposed to detect the pedestrians or vehicles from the highly similar background. Specifically, we design a guide-learning-based multi-scale detection network (GLNet) to distinguish the weak semantic distinction between the pedestrian and its similar background, and output an accurate segmentation map to the autonomous driving system. The proposed GLNet mainly consists of a backbone network for basic feature extraction, a guide-learning module (GLM) to generate the principal prediction map, and a multi-scale feature enhancement module (MFEM) for prediction map refinement. Based on the guide learning and coarse-to-fine strategy, the final prediction map can be obtained with the proposed GLNet which precisely describes the position and contour information of the pedestrians or vehicles. Extensive experiments on four benchmark datasets, e.g., CHAMELEON, CAMO, COD10K, and NC4K, demonstrate the superiority of the proposed GLNet compared with several existing state-of-the-art methods. IEEEAccession Number: 20232114129082 -
Record 523 of
Title:Multi-scale Local Intensity and Gradient Networks for Infrared Small Target Detection
Author(s):Zhao, Zehao(1,2,4); Ma, Yukun(3); Chen, ZhiQiang(1,2,4); Hao, Wang(1,2,4); Chen, Yaohong(1,2,4)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12921 Issue: null Article Number: 129214E DOI: 10.1117/12.2691798 Published: 2023Abstract:Robust small infrared target detection has becoming increasingly important in security and defense applications. Current detection methods can be divided into two parts.The performance of the model-driven methods is limited by the prior assumption parameters, while data-driven methods perform poor in semantic feature extraction due to the lack of the shape characteristic. In this paper, we proposed to embed a model-driven module into a convolution network, which has clear advantages on detection performance and running time. Our method consists of a backbone based on dilated convolution, a multi-scale local intensity and gradient module, and a segmentation head. Experimental results using extended SIRST dataset demonstrated that the proposed method achieves a good balance between the detection performance and running time. ? 2023 SPIE.Accession Number: 20234815132696 -
Record 524 of
Title:Configuration of the active region for the Ge-on-Si photodetector based on carrier mobility
Author(s):Chang, Chang(1,2); Xie, Xiaoping(1,2); Li, Tiantian(3); Cui, Jishi(4)Source: Frontiers in Physics Volume: 11 Issue: null Article Number: 1150684 DOI: 10.3389/fphy.2023.1150684 Published: 2023Abstract:The design of vertical and lateral PIN Ge-on-Si photodetectors was motivated by the disparity in electron and hole mobilities. In the case of vertical PIN junction detectors, configuring the slab region as n-type doping leads to a notable increase in the bandwidth of approximately 20?GHz compared to utilizing p-type doping for the slab. For lateral PIN junction detectors, we determined that setting the length of the n-type slab region to be 2.8?times that of the p-type slab region, based on the carrier saturation drift rate ratio, does not compromise the bandwidth. This configuration enhances the bandwidth while minimizing light absorption loss from the electrode. The proposed design in this study enhances the performance of Ge-on-Si photodetectors without adding complexity to the fabrication process. The principles applied in this study serve as instructive references for the conceptualization of other photonic or electronic devices, reinforcing the widespread applicability of these design strategies. Copyright ? 2023 Chang, Xie, Li and Cui.Accession Number: 20233514653987 -
Record 525 of
Title:A Method of Design and Evaluation of X-ray Communication in Black-Out Area
Author(s):Xia, Fangyuan(1,2,3); Wang, Bo(1); Zhang, Guoting(1); Yuan, Yabo(1); Wu, Jian(2); Zhang, Yingjun(3); Li, Yao(4,6); Zhang, Furui(4,6); Tan, Zhenkun(4); Du, Yun(5); Su, Tong(6)Source: Lecture Notes in Electrical Engineering Volume: 996 LNEE Issue: null Article Number: null DOI: 10.1007/978-981-19-9968-0_19 Published: 2023Abstract:In order to solve the communication problem in black-out area caused by the hypersonic vehicle or re-enter spacecraft, a communication scheme is proposed based on X-ray for electromagnetic shielding of complex media. The principle of laser-X-ray conversion module has been analyzed. According to the space application environment, the X-ray generation model is established by using the Monte Carlo software (MCNP), and the optimal metal target thickness and photon conversion efficiency of the transmission structure are simulated against different load environments. On this basis, the engineering model of space X-photon transmission is deduced. Combined with the existing core component level, the effective transmission rate of X-ray control signal under different communication distances is estimated. Simulated results point out that the X-ray band carrier transmission network can penetrate the black-out plasma medium with an electron density of 1017/m3 order at a distance of 20 km and realize the information transmission at the rate of 75 kps and the bit error rate of 10–6, which provides technical support for cracking the reliable transmission of information in complex electromagnetic environment. ? 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Accession Number: 20231113734071 -
Record 526 of
Title:Design of Large Field of View Multi-Spectral Off-Axis Three-Mirror Reflective Optical System
Author(s):Zhao, Jiawen(1,2); Li, Xuyang(1,2); Ren, Zhiguang(1,2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12559 Issue: null Article Number: 125590C DOI: 10.1117/12.2651744 Published: 2023Abstract:Aiming at the application requirements of space remote sensing observation of light and small multispectral imaging technology, a wide field of view multispectral small off-axis three-mirror optical system based on linear gradient filter is designed. The spectral coverage range is 430nm ~ 900nm, the field of view is 6.3 °×4.5 °, F number is 8. The focal length of the optical system is 350 mm, and the system uses staring scanning to image the ground. The detector is 8424 × 6032 array detector, the pixel size is 4.6μm. The light splitter adopts linear gradient filter, and the aperture diaphragm is set at the secondary mirror, so that the size of the main mirror is close to that of the three mirrors, and the size of the whole system is reduced. Finally, the design results show that the whole system has compact structure and good imaging quality. The modulation transfer function (MTF) of the optical system in each spectrum band of the full field of view is greater than 0.3 at the Nyquist frequency of 108lp/mm. MTF and Spot Diagrams are close to the diffraction limit, which can meet the application requirements. ? 2023 SPIE.Accession Number: 20230613559815 -
Record 527 of
Title:A Generic Multispectral Demosaicking Method Based on Inter-channel Spectrum Correlation
Author(s):Zhang, Xuejun(1,2); Zhang, Geng(1); Hu, Bingliang(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12921 Issue: null Article Number: 1292113 DOI: 10.1117/12.2688177 Published: 2023Abstract:Multispectral images have more spectral bands compared to RGB color images and also contain more information. Therefore, multispectral images have a wide range of applications, including atmospheric environment detection, medical diagnostics, agricultural disease detection, and food monitoring. Because acquiring raw multispectral images requires embedding multiple cameras and various mechanical and optical components to image them once, these systems are very heavy and not inexpensive, so their use is limited. In order to solve these problems, a kind of sensor technology called multispectral filter array (MSFA) has become a hot topic and gradually developed. Snapshot multispectral imaging based on msfa can lead to severe sparsity in each channel of the original captured image. Each pixel on the detector based on MSFA only responds to the optical information of the corresponding spectral band, so the other spectral band information of the pixel is lost. We refer to the original image captured based on MSFA as mosaic image. In order to obtain multiple single spectral band images with full resolution, we need to carry out a process called demosaicking on the original image. In this article, we present a generic demosaicking approach based on inter-channel spectrum correlation. In order to verify the effect of the proposed approach, we conducted some validation experiments on a public database. Experimental results show that the proposed approach is better than the classical methods in spatial reconstruction and spectral accuracy. ? 2023 SPIE.Accession Number: 20234815132590 -
Record 528 of
Title:A Fast Non-local Means Algorithm for Phase Diversity Technique to Reconstruct High-resolution Multi-aperture Images
Author(s):Zhang, Yating(1,2); Zhao, Hui(1); Yang, Mingyang(1); Xie, Xiaopeng(1); Wang, Pengfei(1,2); Li, Baopeng(1); Fan, Xuewu(1); Li, Chuang(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12766 Issue: null Article Number: 127660W DOI: 10.1117/12.2686674 Published: 2023Abstract:Phase diversity technique (PD) can jointly estimate the wavefront aberration and the target image of an optical imaging system. The PD technique reconstructs images by acquiring a focal plane image of optical system and one or more images with known aberrations (often selected defocus). Due to the simple construction of the optical system, the ability to detect discontinuous co-phase errors, and its applicability to both point sources and extended targets, The PD technique is uniquely suited for spatial target imaging applications, especially for the detection of multi-aperture piston errors. However, in a spatially low-illumination environment, Poisson noise as the main noise source of the imaging system seriously affects the accuracy of the reconstructed images. In this paper, we propose a method of phase diversity technique based on a fast Non-local Means (NLM) algorithm for reconstructing single-aperture images or multi-aperture images. For the two cases of single-aperture imaging and multi-aperture imaging with piston errors in spatial low illumination conditions, the method is used to solve the sensitivity problem of Poisson noise during image reconstruction. Numerical simulation results show that our method has significant improvement in structural similarity of the recovered images compared with the traditional phase diversity technique, and also is faster than the common non-local mean algorithm. The combination of this fast non-local means algorithm which using integral images and the phase diversity technique greatly reduce the computation time. The field experimental results and simulation results show good agreement. The new method would be useful in the AO system with active Poisson noise. ? 2023 SPIE.Accession Number: 20235215267983