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Infection by bacteria leads to tissue damage and inflammation, which need to be tightly controlled by host mechanisms to avoid deleterious consequences. It is previously reported that TMEM16F, a calcium‐activated lipid scramblase expressed in various immune cell types including T cells and neutrophils, is critical for the control of infection by bacterium Listeria monocytogenes (Lm) in vivo. This function correlated with the capacity of TMEM16F to repair the plasma membrane (PM) damage induced in T cells in vitro, by the Lm toxin listeriolysin O (LLO). However, whether the protective effect of TMEM16F on Lm infection in vivo is mediated by an impact in T cells, or in other cell types, is not determined. Herein, the immune cell types and mechanisms implicated in the protective effect of TMEM16F against Lm in vivo are elucidated. Cellular protective effects of TMEM16F correlated with its capacity of lipid scrambling and augment PM fluidity. Using cell type‐specific TMEM16F‐deficient mice, the indication is obtained that TMEM16F expressed in liver Kupffer cells (KCs), but not in T cells or B cells, is key for protection against Listeria in vivo. In the absence of TMEM16F, Listeria induced PM rupture and fragmentation of KCs in vivo. KC death associated with greater liver damage, inflammatory changes, and dysregulated liver metabolism. Overall, the results uncovered that TMEM16F expressed in Kupffer cells is crucial to protect the host against Listeria infection. This influence is associated with the capacity of Kupffer cell‐expressed TMEM16F to prevent excessive inflammation and abnormal liver metabolism. [ABSTRACT FROM AUTHOR]

To prepare a high quality Fe-based ceramic composite coating, 17-4ph+30% WC alloy powder was clad onto a 17-4ph stainless steel substrate by high speed laser cladding (HSLC) and a metal matrix composite (MMC) clad without cracks and pores was achieved. The WC particle distribution, microstructure formation and evolution mechanism of the MMC laser clad were studied in detail. The results show that the phase composition of the MMC laser clad mainly includes γ-Fe, W2C, WC, Ni3Fe, Cr23C6, etc. The WC particles in the MMC laser clad show a good metallurgical bonding with the 17-4ph substrate, the dilution rate of the clad is low and the higher heat input causes more WC particles to melt and decompose, generating more hard strengthening phases. The grain refinement strengthening, solid solution strengthening and second phase strengthening are more prominent, which provides a scientific basis for optimizing the preparation of high quality Fe-based ceramic composite coatings. [ABSTRACT FROM AUTHOR]

In this paper, a surface with fractal characteristics on the basis of a continuous function has been constructed. We conducted a study on the Box dimension and the Hausdorff dimension of this surface, building upon this foundation. We found that there exists a certain relationship between the dimensionality of the surface with fractal characteristics, which is obtained from the rotation of a fractal curve. [ABSTRACT FROM AUTHOR]

The coal mine roller is a key component in the mine belt conveyor system. The work described herein involved a Fe-based clad prepared on a 42CrMo steel roller substrate by laser cladding in order to improve the service life and performance of the coal mine roller. The chemical composition, microstructure, properties, microhardness, wear resistance and salt spray corrosion performance of the laser clad layer and substrate under the optimum process parameters were systematically studied. The results showed that laser scanning speed and laser power mainly affect the width, height and depth of the clad. The process parameters were optimized by a series of orthogonal experiments. The optimal process parameters were a laser power of 1700 W, scanning speed of 6 mm/s and powder feed rate of 15 g/min. The laser clad mainly composed γ-Fe and the compounds of Fe and Cr, such as CrFe4and CrFe19. Along the depth direction of laser clad the microstructure gradually changed from planar crystal and bits of dendrite crystal to equiaxed crystal. The grains at the top of the direction of the laser cladding layer were further refined. The hardness of the laser clad was increased by about 2.2 times that of the substrate. The friction and the loss of weight from wear test and salt spray corrosion of the laser clad show that the weight gain is much smaller than that of the substrate. The experimental results show that the wear resistance and corrosion resistance are improved significantly. [ABSTRACT FROM AUTHOR]

This study used a potted experiment to apply biochar to black soil (BCS) and saline-alkali soil (BSAS) in Northeast China, with a dosage of 0 and 300 g biochar/pot applied, respectively. The original black soil (CS) and saline-alkali soil (SAS) were used as controls to investigate the effects of different particle sizes of soil aggregates on the activity of enzymes related to carbon, nitrogen, and phosphorus cycle. Compared with CS and SAS, the soil organic matter (SOM) values for biochar added into the black soil (BCS) and saline-alkali soil (BSAS) treatments were increased significantly by 41.86 % and 31.98 %. Compared with CS, BCS significantly increased the polyphenol oxidase and ß-1,4-glucosidase activity. Polyphenol oxidation activity, endo-1,4-ß-D-glucanohydrolase activity, ß-1,4-glucosidase activity and xylanase activity are more active in particles with a diameter of >2 mm. The alkaline phase activity and Coenzyme activity with BCS treatment was highest in soil aggregates with sizes of 1~2 mm and >5 mm, respectively. Mantel test analysis shows a highly significant effects between SOM and total nitrogen content (TN) with soil nitrogen, phosphorus, and potassium cycling. Therefore, from the perspective of soil enzyme activities, application of biochar is more effective in promoting soil bio-fertility in northeastern soil of China. Biochar to the soil is more likely to promote the improvement of soil biological fertility. [ABSTRACT FROM AUTHOR]

PIEZO1 is a mechanosensitive channel that converts applied force into electrical signals. Partial molecular structures show that PIEZO1 is a bowl-shaped trimer with extended arms. Here we use cryo-electron microscopy to show that PIEZO1 adopts different degrees of curvature in lipid vesicles of different sizes. We also use high-speed atomic force microscopy to analyse the deformability of PIEZO1 under force in membranes on a mica surface, and show that PIEZO1 can be flattened reversibly into the membrane plane. By approximating the absolute force applied, we estimate a range of values for the mechanical spring constant of PIEZO1. Both methods of microscopy demonstrate that PIEZO1 can deform its shape towards a planar structure. This deformation could explain how lateral membrane tension can be converted into a conformation-dependent change in free energy to gate the PIEZO1 channel in response to mechanical perturbations. Cryo-electron microscopy and high-speed atomic force microscopy reveal that PIEZO1 can reversibly deform its shape towards a planar structure, which may explain how the PIEZO1 channel is gated in response to mechanical stimulation., Author(s): Yi-Chih Lin [sup.1] [sup.2] , Yusong R. Guo [sup.3] , Atsushi Miyagi [sup.1] [sup.2] , Jesper Levring [sup.3] , Roderick MacKinnon [sup.3] , Simon Scheuring [sup.1] [sup.2] Author Affiliations: [...]

The hydraulic column is the key component of the hydraulic support in the mining environment. To improve a hydraulic column's reliability and service life, the Fe-based laser clad layer was prepared on 27SiMn steel substrate using a high power diode laser (HPDL). The results show that the best process parameters are the laser power of 3000 W, the scanning speed of 5 mm/s, the feeding fraction of 16 g/min and the lapping rate of 50%. The macroscopic morphology of the laser clad layer has no cracks, pits and other defects. The laser clad layer has a fine and uniform microstructure and can form a metallurgical bonding with the 27SiMn steel substrate. Elements distribution is uniform and it appears fluctuation around the melting line. The cladding hardness is 1.3 times higher than the substrate and the wear resistance is 7.7 times higher than the substrate. The self-corrosion potential of the laser clad layer is significantly shifted positively and has a significant passivation region. After 96 hours of salt pray corrosion test, the surface of the laser clad layer is still smooth. The laser clad layer has better corrosion resistance and performance than the substrate, which can meet the requirements of hydraulic support in the mining environment. [ABSTRACT FROM AUTHOR]

Reducing the risk behaviors of drivers during driving is of great significance to improve the level of road traffic safety. Using intelligent technology to monitor unsafe behaviors of drivers can effectively reduce and control the occurrence of unsafe events of drivers, and avoid and reduce casualties and property losses. In this paper, we propose a multiple occurrence point recognition method for traffic unsafe driving behavior based on YOLOv5 visual perception. This method uses media filtering to remove the noise of driving image, divides the image in YOLOv5 network structure, objectifies the image features; uses visual perception to obtain the true aspect ratio, calculates the fatigue coefficient; uses threshold value to judge unsafe driving behavior, and determines the frequent occurrence of unsafe driving through low fimction. The results show that the data SNR of this method can reach 77.ldB, the recall rate can reach 99.0%, and the recognition time is less than 8s, indicating that this method has stronger recognition performance. [ABSTRACT FROM AUTHOR]

A novel NiTi/AlNi2Ti ternary intermetallic alloy were prepared by arc melting. Tribocorrosion behaviors of the NiTi/AlNi2Ti alloy were investigated by tribocorrosion tests. The results showed that NiTi/AlNi2Ti alloy had an excellent tribocorrosion resistance in NaCl solution and is more suitable as a tribocorrosion resistant material than 1Cr18Ni9Ti stainless steel. With the onset of sliding, the OCP of NiTi/AlNi2Ti alloy decreases and the corrosion current density increases during tribocorrosion test, and the decrease of the OCP is proportional to the increase of the frictional force, showing a strong corrosion-wear synergy effect. The corrosion current density and wear loss volume of the NiTi/AlNi2Ti alloy increase with the increase of applied potentials. [ABSTRACT FROM AUTHOR]

The scanning trajectory method of laser cladding has a great influence on the quality of the clad layer. Herein, the effects of single spiral and double spiral trajectories on the clad morphology, temperature gradient and solidification rate of the Fe-based powder clad at different solidification positions during the injection of the cladding powder on a 45 steel elongated slender shaft when cladding with a high power diode laser (HPDL) are investigated. A three-dimensional (3-D) mathematical model was developed. The temperature variation curves of the substrate and the molten coating were obtained by the birth-death cell technique. The influence of the output parameters on the coating quality was analysed and discussed. In order to verify the reliability of the model, experimental tests were carried out to verify the surface quality and tissue morphology of the molten coating under the two scanning methods. The results show that the agreement between the theoretical calculation results and the experimental results is good. In addition, both scanning methods generate pores at the coating laps. The above conclusions are further confirmed by the dimensional change analysis. For this reason, this paper serves as a good guideline for the melting and cladding process of slender shafts. [ABSTRACT FROM AUTHOR]

Author(s): Yugang Wang [1]; Yusong R. Guo [2]; Ke Liu [3]; Zheng Yin [4]; Rui Liu [1]; Yan Xia [1]; Lin Tan [5]; Peiying Yang [5]; Jong-Ho Lee [1]; Xin-jian [...]

We show in the companion paper that the free membrane shape of lipid bilayer vesicles containing the mechanosensitive ion channel Piezo can be predicted, with no free parameters, from membrane elasticity theory together with measurements of the protein geometry and vesicle size [C. A. Haselwandter, Y. R. Guo, Z. Fu, R. MacKinnon, Proc. Natl. Acad. Sci. U.S.A., 10.1073/pnas.2208027119 (2022)]. Here we use these results to determine the force that the Piezo dome exerts on the free membrane and hence, that the free membrane exerts on the Piezo dome, for a range of vesicle sizes. From vesicle shape measurements alone, we thus obtain a force–distortion relationship for the Piezo dome, from which we deduce the Piezo dome’s intrinsic radius of curvature, 42 ± 12 nm, and bending stiffness, 18 ± 2:1 kBT, in freestanding lipid bilayer membranes mimicking cell membranes. Applying these estimates to a spherical cap model of Piezo embedded in a lipid bilayer, we suggest that Piezo’s intrinsic curvature, surrounding membrane footprint, small stiffness, and large area are the key properties of Piezo that give rise to low-threshold, high-sensitivity mechanical gating. [ABSTRACT FROM AUTHOR]

Piezo proteins are mechanosensitive ion channels that can locally curve the membrane into a dome shape [Y. R. Guo, R. MacKinnon, eLife 6, e33660 (2017)]. The curved shape of the Piezo dome is expected to deform the surrounding lipid bilayer membrane into a membrane footprint, which may serve to amplify Piezo’s sensitivity to applied forces [C. A. Haselwandter, R. MacKinnon, eLife 7, e41968 (2018)]. If Piezo proteins are embedded in lipid bilayer vesicles, the membrane shape deformations induced by the Piezo dome depend on the vesicle size. We employ here membrane elasticity theory to predict, with no free parameters, the shape of such Piezo vesicles outside the Piezo dome, and show that the predicted vesicle shapes agree quantitatively with the corresponding measured vesicle shapes obtained through cryoelectron tomography, for a range of vesicle sizes [W. Helfrich, Z. Naturforsch. C 28, 693–703 (1973)]. On this basis, we explore the coupling between Piezo and membrane shape and demonstrate that the features of the Piezo dome affecting Piezo’s membrane footprint approximately follow a spherical cap geometry. Our work puts into place the foundation for deducing key elastic properties of the Piezo dome from membrane shape measurements and provides a general framework for quantifying how proteins deform bilayer membranes. [ABSTRACT FROM AUTHOR]

OBJECTIVES: In exemplar-based image inpainting algorithms, there are often issues with the calculation of patch similarity for matching, suboptimal strategies for selecting matching patches, and low inpainting speed. METHODS: First, large-scale scanning patches are used to scan the known areas of the image line by line to solve the problem of slow scanning speed. When the scanning reaches the area to be repaired, the large-scale scanning patches are adaptively changed to small-scale scanning patches to continue scanning, improving the accuracy of local information inpainting in the image. Then, an improved weighted similarity calculation formula is used to search for similar matching patches, and the search range gradually expands from local to global to improve computational efficiency. To further improve the correctness of the matching patch selection, multiple matching criteria and filtering strategies are used for selection. Finally, the direction of priority inpainting is determined by the stability factor, followed by filling. RESULTS: The experimental results show that the inpainting effect of the proposed method is significantly improved in subjective vision, and the structural similarity (SSIM), peak signal-to-noise ratio (PSNR), and inpainting speed of the inpainting results are all improved. CONCLUSION: For damaged images, texture images, and target removal images, the proposed method has a better inpainting effect and higher inpainting speed than the other three advanced methods. [ABSTRACT FROM AUTHOR]

To evaluate the effect of autologous blood transfusion (ABT) on hematopoietic stem cells through the observation of the changes in the number and activity of bone marrow CD34+ cells after preoperative autologous blood donation (PABD). Rabbit bone marrow specimens were collected preoperatively (T2), 6 h postoperatively (T3), and 24 h postoperatively (T4). Next, the percentages of CD34+ cells, the cell cycle, and the relative expression of telomeric DNA were measured in each group of rabbits. Peripheral blood specimens were collected before PABD (T1) and at T4 to measure reticulocytes. At T3 and T4, the percentages of CD34+ cells and the expressions of telomeric DNA were significantly higher, and the percentages of cells in the G1 phase were significantly lower in each experimental group compared with those in the blank control group (group A) (P<0.05). Compared with the surgical blood collection group (group C), the CD34+ cells and the expressions of telomeric DNA were significantly higher, and the percentages of cells in the G1 phase were significantly lower in the preoperative autologous whole blood group (group D) and the preoperative autologous blood component group (group E) (P<0.05). Compared with group D, the CD34+ cells and the expressions of telomeric DNA were significantly lower, and the percentages of cells in the G1 phase were significantly higher in group E (P<0.05). At T4, the reticulocyte percentages in the surgery group (group B) and group C were significantly higher than in group E and group D, and the reticulocyte percentages in group E were higher than in group D (P<0.05). This study's findings indicated that ABT suppressed bone marrow hematopoiesis, while autologous blood component transfusion had less of an effect than that of whole blood transfusion. Therefore, PABD blood component transfusion would be superior to autologous whole blood transfusion. [ABSTRACT FROM AUTHOR]