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The aim of this work is to investigate the effect of different second phases on the composite spinning-extrusion forming and mechanical properties of Al–Cu–Li alloy. With that purpose, four kinds of second phases blanks were controlled using preheating treatment, composite spinning-extrusion forming and mechanical properties test. Then, the correlation between the second phases and mechanical properties was further analyzed using electron backscattered diffraction and transmission electron microscopy. The results indicated that different second phases of Al–Cu–Li alloy can be regulated via reasonable preheating treatment. In addition, different second phases in the blank have various influences on composite spinning-extrusion forming, microstructure and mechanical properties of cylindrical parts. Dissolving the coarse second phases particles and precipitating the Al3Zr dispersoid in the blank can effectively improve the composite spinning-extrusion forming, inhibit the abnormal growth of recrystallized grains, and significantly enhance the mechanical properties of cylindrical parts with ribs. After regulation, the average grain size of the cylindrical parts is refined from about 90 μm to about 45 μm, and the average diameter of T1 phase is refined from 107 nm to 77 nm. In addition, the ultimate tensile strength, yield strength and elongation of cylindrical parts are increased from 555 MPa to 588 MPa, 530 MPa to 564 MPa, and 9.1% to 11%, respectively.

A novel single-pixel imaging (SPI) technique based on discrete orthogonal Zernike moments is proposed. In this technique, the target object is illuminated by two sets of Zernike basis patterns which satisfy the Zernike polynomials. The Zernike moments of object image are obtained by measuring the reflected light intensities through a single-pixel detector. And the object image is reconstructed by summing the product of Zernike polynomials and detected intensities iteratively. By theoretical and experimental demonstrations, an image with high quality is retrieved under compressive sampling. Moreover, the Zernike illuminating patterns are used for object classification due to the rotation invariant of Zernike moments. By measuring the amplitudes of a few specific Zernike moments through the SPI system, the rotated images with different angles and the same content are classified into the same class on experiment. This classification technique has the advantages of high efficiency and high accuracy due to the high modulation speed and high sensitivity of SPI system.

Ozone (O3) has attracted considerable attention due to its harmful effects on the ecosystem and human health. The Yangtze River Delta (YRD), China in particular has experienced severe O3 pollution in recent years. Here, we conducted a long-term observation of O3 in YRD to reveal its characteristics. The O3 concentration in autumn was the highest at 72.76 ppb due to photochemical contribution and local convection patterns, with its lowest value of 2.40 ppb in winter. O3 exhibited strong diurnal variations, showing the highest values in the early afternoon (15:00–16:00) and the minimum in 07:00–08:00, specifically, peroxyacetyl nitrate (PAN) showed similar variations to O3 but PAN peak usually occurred 1 h earlier than that of O3 due to PAN photolysis. A generalized additive model indicated that the key factors to O3 formation were NO2, PAN, and temperature. It was found that a certain temperature rise promoted O3 formation, whereas temperatures above 27 °C inhibited O3 formation. An observation-based model showed O3 formation was VOCs-limited in spring and winter, was NOx-limited in summer, and even controlled by both VOCs and NOx in autumn. Thus, prevention and control strategies for O3 in the YRD are strongly recommended to be variable for each season based on various formation mechanisms.

Single-pixel imaging (SPI) is a new technology with many applications and prospects. Polarization detection technology can improve the detection and identification ability of the imaging system. A near-infrared polarization SPI lidar system is designed to realize detection and polarization imaging of outdoor long-range targets. The depth, intensity, linear polarization, and polarization degree images of typical remote targets are obtained. The results show that the polarization image contains many details and contour information of the target, and the intensity image contains brightness and reflectivity information. Intensity and polarization information complement each other. The characteristics of intensity and polarization images at different spatial frequencies are analyzed for the first time, to our knowledge, by taking advantage of the Fourier modulation mode. We found that the proportion of high-frequency information in the polarization image is much higher than that of the intensity image. The sampling strategy of collecting only low-frequency components is applicable in intensity imaging but needs further improvement in polarization imaging. The polarization SPI lidar system can enrich the target information acquired, improve imaging contrast, and have significant application value for target detection and identification in complex backgrounds.

Deoxynivalenol (DON), as a secondary metabolite of fungi, is continually detected in livestock feed and has a high risk to animals and humans. Moreover, pigs are very sensitive to DON. Recently, the role of histone modification has drawn people's attention; however, few studies have elucidated how histone modification participates in the cytotoxicity or genotoxicity induced by mycotoxins. In this study, we used intestinal porcine epithelial cells (IPEC-J2 cells) as a model to DON exposure in vitro. Mixed lineage leukemia 1 (

To test the hypothesis that stay-green genotypes help to increase stalk lodging resistance under high planting density by reducing dry matter remobilization from stalk, a two-year field study with three planting densities (60,000, 75,000, and 90,000 plants per ha) and six hybrids was conducted. When planting density changed from 75,000 to 90,000, stalk dry matter remobilization efficiency increased by 4.1–191%. Stem dry weight per length, rind penetration strength, average crushing strength for the first to fifth internode, and average bending strength for the third to fifth internode decreased by 25.4–47.2%, 5.1–24.6%, 1.4–29.9%, and 14.0–36.0%, respectively. Stalk lodging rate increased by 17–275%. Stalk dry matter remobilization efficiency was negatively correlated to either stem dry weight per length (r = 0.23, p

Target tracking has found important applications in particle tracking, vehicle navigation, aircraft monitoring, etc. However, employing single-pixel imaging techniques to track a fast-moving object with a high frame rate is still a challenge, due to the limitation of the modulation frequency of the spatial light modulator and the number of required patterns. Here we report a complementary single-pixel object tracking approach which requires only two geometric moment patterns to modulate the reflected light from a moving object in one frame. Using the complementary nature of a digital micromirror device (DMD), two identical single-pixel detectors are used to measure four intensities which can be used to acquire the values of zero-order and first-order geometric moments to track the centroid of a fast-moving object. We experimentally demonstrate that the proposed method successfully tracks a fast-moving object with a frame rate of up to 11.1 kHz in the first two experiments. In the third experiment, we compare previous works and find that the method can also accurately track a fast-moving object with a changing size and moving speed of 41.8 kilopixel/s on the image plane. The root mean squared errors in the transverse and axial directions are 0.3636 and 0.3640 pixels, respectively. The proposed method could be suitable for ultrafast target tracking.

When imaging moving objects, single-pixel imaging produces motion blur. This paper proposes a new single-pixel imaging method, which can achieve anti-motion blur imaging of a fast-moving object. The geometric moment patterns and Hadamard patterns are used to alternately encode the position information and the image information of the object with time-division multiplexing. In the reconstruction process, the object position information is extracted independently and combining motion-compensation reconstruction algorithm to decouple the object motion from image information. As a result, the anti-motion blur image and the high frame rate object positions are obtained. Experimental results show that for a moving object with an angular velocity of up to 0.5rad/s relative to the imaging system, the proposed method achieves a localization frequency of 5.55kHz, and gradually reconstructs a clear image of the fast-moving object with a pseudo resolution of 512x512. The method has application prospects in single-pixel imaging of the fast-moving object., Comment: 13 pages,7figures

Post-weaning diarrhea (PWD) is frequently associated with E. coli F18 infections in piglets. However, the underlying molecular mechanism concerning the resistance of E. coli F18 in local weaned piglets in China is not clearly understood. In the present study, by a comparative analysis of the transcriptome, a-1,3-fucosyltransferase (FUT3) was evaluated as a key candidate correlated with resistance to E. coli F18 in Sutai and Meishan piglets. Functional analysis demonstrated that FUT3 acts as a key positive regulator of E. coli F18 susceptibility in newly food accustomed piglets. However, the core promoter of FUT3 was present at −500–(−206) bp (chr.2: g.73171117–g.73171616), comprising of 9 methylated CpG sites. Among these, the methylation levels of the two CpG sites (mC-3, mC-5) located in HIF1A and Sp1 transcription factor (TF) considerably associated with mRNA expression of FUT3 (p &lt, 0.05). Our findings indicated that the methylation of mC-3 and mC-5 sites has certain inhibitory effect on FUT3 expression and promotes the resistance of E. coli F18 in piglets. The underlined study may explore FUT3 as a new candidate target in E. coli F18 infection in Chinese local weaned piglets.

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign or low-grade malignant tumor, but it has the potential to present with multiple lesions, lymph node metastasis, extra-pulmonary metastasis, recurrence and even cause death. Herein, a case of PSP that was huge, presented with multiple lesions and had lymph node as well as extrapulmonary metastases (liver, abdominal cavity, bones) is reported for the first time. This patient was also the first one to die of respiratory and circulatory failure caused by the PSP tumor and its metastases which compressed the mediastinal tissue.

Successive images of a scene are captured and then further processed to achieve the moving object tracking. However, due to modulation rate limitations of the spatial light modulator in single-pixel imaging (SPI) system, the imaging frame rate cannot meet the high-resolution and real-time requirements for object tracking. In this paper, we demonstrate a fast object tracking technique based on SPI with an ultra-low sampling rate that is independent of imaging. We construct modulation information that satisfies the projection conditions and can transform 2D images into 1D projection curves. The 1D projection curves, which provide the location information of the moving object, can be obtained with high resolution in real-time, and then the tracking of the moving object is realized. A background subtraction technique for tracking moving objects that removes static components from a scene is also proposed. The proposed technique is verified by computational simulations and laboratory experiments. In the laboratory experiments, we demonstrate that the proposed method can be used to track moving objects with less than 0.2% of the measurements established by the Nyquist criterion, and it presents 256 × 256 pixels at ∼ 177 fps. The reported technique accelerates the tracking speed of SPI and provides an efficient strategy for remote sensing and biomedical applications.

In previous studies, numerous dysregulated lncRNAs were identified using RNA-sequencing. Lung cancer is the most common malignant tumour worldwide and the second leading cause in cancer. The aim of this study is to investigate the function and mechanism of lincRNA00858 in the lung cancer. RT-PCR was used to detect the expression of lincRNA00858. Proliferation, invasion, and epithelial-mesenchymal transition (EMT) were examined by CCK8, transwell assay and western blot to evaluate the function of linc00858. Dual-luciferase reporter assay was used to identified the potential target of linc00858. Over-expression of linc00858 significantly promoted cell proliferation, invasion. We also found that linc00858 facilitated the EMT process. Dual-luciferase reporter assay revealed that linc00858 can bind with miR-3182 directly. Linc00858 can negatively regulate the expression of miR-3182. Further experiments demonstrated that MMP2 was the direct target of miR-3182. Rescue experiments revealed that linc00858 functioned through miR-3182/MMP2 axis. Taken together, we verified the role of an unknown linc00858 in lung cancer and provided its mechanism. Mechanistically, linc00858 acted as a competitive endogenous RNA to sponged miR-3182 and regulate MMP2 in lung cancer. Our study provided new clues for understanding the mechanism of lung cancer.

Long-range light detection and ranging (lidar) of active illumination optical imaging has widespread applications, such as remote sensing, satellite-based global topography, and target recognition and identification. Here, to make trade-offs among imaging efficiency, resolution, receiving field of view, divergence angle, and detected distance, we demonstrate a scanning single-pixel imaging lidar (SSPIL), enjoying the merits of the traditional pointing-by-pointing scanning imaging and single-pixel imaging. The imaging strategy of SSPIL is divided into scanning search and staring imaging processes. These strategies can save most time consumption for imaging background areas and thus improve imaging efficiency. Three imaging experiments were conducted in real urban atmospheric conditions. The preliminary results show SSPIL has the ability for long-range imaging with high efficiency, high resolution, and a large receiving field of view. Also, from the imaging results, we found that multiple samples can improve the SNR of imaging in the real urban atmosphere. The present work may provide a valuable alternative approach in the long-range active illumination optical imaging fields.

The information dimension obtained by multispectral ghost imaging is more abundant than in single-band ghost imaging. Existing multispectral ghost imaging systems still meet some shortages, such as complex structure or reconstruction time-consuming. Here, an approach of cosinusoidal encoding multiplexed structured illumination multispectral ghost imaging is proposed. It can capture the multispectral image of the target object within one projection cycle with a single-pixel detector while maintaining high imaging efficiency and low time-consuming. The core of the proposed approach is the employed novel encoding strategy which is apt to decode and reconstruct the multispectral image via the Fourier transform. Specifically, cosinusoidal encoding matrices with specific frequency characteristics are fused with the orthogonal Hadamard basis patterns to form the multiplexed structured illumination patterns. A broadband photomultiplier is employed to collect the backscattered signals of the target object interacted by the corresponding structured illumination. The conventional linear algorithm is applied first to recover the mixed grayscale image of the imaging scene. Given the specific frequency distribution of the constructed cosinusoidal encoding matrices, the mixed grayscale image can be converted to the frequency domain for further decoding processing. Then, the pictures of multiple spectral components can be obtained with some manipulations by applying Fourier transform. A series of numerical simulations and experiments verified our proposed approach. The present cosinusoidal encoding multiplexed structured illumination can also be introduced in many other fields of high-dimensional information acquisition, such as high-resolution imaging and polarization ghost imaging.

This study investigated the twinning behavior with increasing compressive strain in rolled AZ31 alloy. With that purpose, a polycrystalline structure with an average grain size of 30 μm was utilized to perform the uniaxial compression tests. Microstructure evolution was traced by in situ electron backscattered diffraction (EBSD). Multiple primary twin variants and extension double twins were observed in the same grain. A comprehensive analysis of kernel average misorientation (KAM) and Schmid factor (SF) revealed that the nucleation of twins in one special grain is not only based on the SF criterion, but that it is also strongly influenced by surrounding grains. Moreover, the existing primary twins modified the inner and outer strain distribution close to the twin boundaries. With continued compression, the strain inside the primary twins stimulated the nucleation of double twins, while the strain in the matrixes facilitated twin growth. Therefore, the primary twin growth and the new nucleation of secondary twins could take place simultaneously in the same twinning system to meet the requirements of strain accommodation. Twinning behaviors are controlled by the combined effect of the Schmid factor, strain accommodation between surrounding grains, and variation in the local stress state. The local stress exceeded the critical resolved shear stress (CRSS), implying that twin nucleation is possible. Hence, the twinning process tends to be a response of the local stress rather than the applied stress.

Single-pixel imaging (SPI), a novel computational imaging technique that has emerged in the past decades, can effectively capture the image of a static object by consecutively measuring light intensities from it. However, when SPI is applied to imaging the dynamic object, severe motion blur in the restored image tends to appear. In this Letter, a new SPI scheme is proposed to largely alleviate such a problem by leveraging a calibrated radon spectrum. Such a spectrum is obtained by translating the acquired one-dimensional projection functions (1DPFs) according to the positional relationship among the 1DPFs. Simulation and experimental results demonstrate that, without prior knowledge, our approach can effectively reduce motion blur and restore high-quality images of the fast-moving object. In addition, the proposed scheme can also be used for fast object tracking.

Trajectory prediction of surrounding objects plays a pivotal role in the field of autonomous driving vehicles. In the current rollout process, it suffers from an accumulation of errors, which has a negative impact on prediction accuracy. This paper proposes a parametric-learning recursive least-squares (RLS) method integrated with an encoder–decoder framework for trajectory prediction, named the recursive least-squares-based refinement network (RRN). Through the generation of several anchors in the future trajectory, RRN can capture both local and global motion patterns. We conducted experiments on the prevalent NGSIM and INTERACTION datasets, which contain various scenarios such as highways, intersections and roundabouts. The promising results indicate that RRN could improve the performance of the rollout trajectory prediction effectively.

A simple and versatile strategy, denominated Slip Trace - Modified Lattice Rotation Analysis (ST-MLRA), is presented to enable the identification of the active slip systems in polycrystalline alloys from surface information. The slip plane trace orientation is used to define the potential active slip planes while the actual slip direction within the active slip plane is obtained from the grain rotation, as indicated by the stretching of the trace of the grain orientation in the pole figure as a result of deformation. Examples of application of the strategy in a HCP Mg alloy are presented for illustration. They show that the strategy is simple to implement and allows to identify the active slip system(s) in each grain.

A new severe plastic deformation method, viz. integrated dual-directional extrusion and spiral deformation, was adopted to process AZ31 Mg alloy and found to be very effective for refining the grains and softening the texture. We also investigated how twinning in AZ31 alloy affected the dynamic recrystallization (DRX) during hot extrusion, revealing that multiple twins can offer increased nucleation sites and enough energy to trigger DRX. Moreover, even after dual-directional extrusion and spiral deformation, a misorientation angle of ~ 86° remained between the primary tension twin and matrix or ~ 60° between the secondary tension twin and primary twin, being induced by {10–12} tension twin variants (primary and secondary) and resulting in a dispersed misorientation angle distribution. Nucleation of DRX occurred at the tip of preexisting twins, although primary and secondary tension twins can also act as nucleation sites for DRX.