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Due to seasonal climate alterations, the microstructure and permeability of granite residual soil are easily affected by multiple dry-wet cycles. The X-ray micro computed tomography (micro-CT) acted as a non-destructive tool for characterizing the microstructure of soil samples exposed to a range of damage levels induced by dry-wet cycles. Subsequently, the variations of pore distribution and permeability due to dry-wet cycling effects were revealed based on three-dimensional (3D) pore distribution analysis and seepage simulations. According to the results, granite residual soils could be separated into four different components, namely, pores, clay, quartz, and hematite, from micro-CT images. The reconstructed 3D pore models dynamically demonstrated the expanding and connecting patterns of pore structures during dry-wet cycles. The values of porosity and connectivity are positively correlated with the number of dry-wet cycles, which were expressed by exponential and linear functions, respectively. The pore volume probability distribution curves of granite residual soil coincide with the χ2 distribution curve, which verifies the effectiveness of the assumption of χ2 distribution probability. The pore volume distribution curves suggest that the pores in soils were divided into four types based on their volumes, i.e. micropores, mesopores, macropores, and cracks. From a quantitative and visual perspective, considerable small pores are gradually transformed into cracks with a large volume and a high connectivity. Under the action of dry-wet cycles, the number of seepage flow streamlines which contribute to water permeation in seepage simulation increases distinctly, as well as the permeability and hydraulic conductivity. The calculated hydraulic conductivity is comparable with measured ones with an acceptable error margin in general, verifying the accuracy of seepage simulations based on micro-CT results.

While the anisotropy of sedimentary soil—particularly the underlying role of soil structure—is well understood, similar knowledge about granite residual soil formed by weathering is scarce. In particular, the evolution of soil structure during the hollow cylinder torsional shear tests (among the most appropriate for studying soil strength anisotropy) remains largely unknown. This study systematically investigates the multiscale structural properties of granite residual soil using stereo microscopy, scanning electron microscopy, energy-dispersive spectrometry, and computed tomography. Furthermore, the structural evolution during hollow cylinder torsional shear tests is traced. Results indicate the strength anisotropy of residual soil is associated with horizontal fissures which cause low shear strength when the soil is sheared with a principal stress direction of 45°. The cementation via Fe is characterized by a uniform distribution. Different evolutionary patterns are observed for soils within the shear band, inside the necking area, and in other regions. It is not always the case that particles are rearranged with their long axis perpendicular to the major principal stress. This study improves the understanding of natural residual soil structure and provides some insights into its anisotropic behavior.

The oxidation and structural properties of hazelnut protein prepared from a low-temperature cold-pressed hazelnut meal were evaluated using three oxidative modification methods: AAPH (2,2'-azo(2-methylpropionamidine)dihydrochloride), MDA (malondialdehyde), and H2O2. The three different oxidants gradually increased the carbonyl content of the proteins, MDA from 1.91 to 8.87 nmol/m, AAPH (from 2.13 to 12.18 nmol/mg, and H2O2 from 2.28 to 13.72 nmol/mg, indicating that the hazelnut protein was oxidized. The carbonyl content of H2O2-modified hazelnut proteins was the highest, implying that the proteins were more susceptible to oxidation by hydroxyl radicals. FT-IR, intrinsic fluorescence spectra, surface hydrophobicity, and protein electrophoresis implied that oxidative modifications altered the secondary structure of hazelnut proteins, and promoted protein aggregation and cross-linking. In addition, the oxidative modification resulted in a larger particle size distribution of hazelnut proteins and a decrease in the zeta potential absolute value, indicating a decrease in the hazelnut proteins stability and the formation of soluble aggregates. Overall, incubation with AAPH, MDA, and H2O2 significantly affected the structure of hazelnut proteins, demonstrating that hazelnut proteins in food processing systems are susceptible to structural and property changes due to different oxidation products.

A class of global exponential synchronization problem for delayed quaternion-valued neural networks with stochastic impulses has been investigated in this paper, where the impulses arouse time and strength both are randomly. Firstly, the delayed quaternion-valued model with stochastic impulses was fain to separate to four real-valued parts in consideration of the fact that noncommutativity character of quaternion multiplication. Then, a new criterion was obtained to achieve the global exponential synchronization via building an appropriate classically Lyapunov candidate function and utilizing the method of comparison principle and reduction to absurdity. Finally, in order to verify the validity of the proposed theorem, a given numerical example is provided.

The climate is a significant factor affecting the collapsing gully in weathered granite areas, and most of the surface layers of the collapsed area comprise granite residual soil. Granite residual soil has complex disintegration characteristics under different initial water content conditions. Besides, its disintegration characteristic is an essential factor for collapsing gully. Therefore, disintegration tests, triaxial shear tests, nuclear magnetic resonance tests, and hydraulic conductivity tests are conducted under torridity and rainstorm conditions in order to study the disintegration characteristics of granite residual soil. The results of disintegration test showed that the initial disintegration rate of granite residual soil increased rapidly with the decrease in water content, while the relationship between disintegration rate and water content in the later stage of disintegration is unclear. When soaked, the maximum decrease in cohesion was 44.48%, the hydraulic conductivity became six times larger, and the amplitude of the T 2 curve increased by about 40%, which reduced the strength of the soil and provided better access for rainwater infiltration to deeper stratum. The results show that the microstructure of granite residual soil would be damaged and the disintegration would occur after a rainstorm at low water content. Micropores would be formed inside the sample after soaking, resulting in destroying the continuity of the material.

The pseudo-potential lattice Boltzmann (LB) model is versatile in modeling multiphase flows since the mesoscopic interaction potential enables it to directly describe the nonideal effect evading the tracking or integrating of phase interface. In this paper, we develop an effective pseudo-potential lattice Boltzmann model to simultaneously realize the thermodynamic consistency, the extremely large density ratio, and the adjustable surface tension. Decoupling the mesh space from the momentum space by a scale factor, denser lattice nodes depict the transition region more accurately. The high-precision explicit finite difference method (EFM) further enhances the calculation accuracy of interaction force. The present model is validated to satisfy thermodynamic even at very low temperature, where the liquid–gas density ratio exceeds 1010. The spurious current can be suppressed to a very low level (

Simple and effective hybrid interpolation method for IC-GN2 DVC algorithm

With the introduction of quaternion number and memristor connection weights, the quaternion-valued memristive neural networks (QVMNNs) is then constructed. Based on the differential theory and quaternion feature, the finite-time boundedness problem of QVMNNs is considered in both quaternion area and complex area. Theorems for guaranteeing finite-time boundedness of QVMNNs are achieved by appropriately choosing the Lyapunov functional and applying linear matrix inequality (LMI). Finally, a simulation example is presented to demonstrate our results.

English version is updated!, {"references":["Accurate and simple digital volume correlation using pre-interpolation. http://doi.org/10.5281/zenodo.3600641"]}

This paper presents the mechanism of five different algorithms for the type of unbalance dip, compared the results based on measured voltage dip by these algorithms. Apply three algorithms to calculate the type of unbalance dip for some typical cases. A conclusion is that there are large differences in results when applying the different algorithms to measured voltage dips. For two of the algorithms it is recommended against application or further development

Uncoupling protein 2 (UCP2), an anion transporter, modulates the production of mitochondrial reactive oxygen species (ROS) and plays an important role in protecting against cell apoptosis. However, the role of UCP2 in sepsis-associated AKI remains unclear. In the present study, we investigated the role of UCP2 in LPS-induced AKI in vitro and in vivo. UCP2 expression was increased in tubular epithelial cells (TECs) treated with LPS. Accordingly, UCP2 expression was distinctly upregulated in renal tissues from the animals with LPS-induced AKI. Furthermore, UCP2 silencing dramatically aggravated LPS-induced apoptosis, accompanied by increased ROS production in renal tubular epithelial cell. Additionally, the inhibition of UCP2 by genipin, a specific UCP2 inhibitor, exacerbated the kidney injury of animals with LPS-induced AKI. Moreover, NAC (N-acetylcysteine), a potent ROS scavenger, obviously suppressed apoptosis induced by UCP2 silencing, which suggests that the increased ROS levels were associated with tubular epithelial cell apoptosis induced by UCP2 silencing. Therefore, UCP2 exerts a protective effect on the LPS-induced apoptosis of tubular epithelial cells by reducing excess ROS production. In conclusion, our findings highlight the renoprotective actions of UCP2 on inhibiting the production of apoptotic factors and oxidative stress to improve tubular cell survival in the LPS-induced AKI model.

In order to study the evolution of cracks in the initial disintegration process of granite residual soil, this study used CT scanner to scan the sample before and after 60s disintegration. Internal cracks are statistically analyzed by 3D reconstruction techniques. The initial crack content of granite residual soil is 0.8%, and it increases to 8.1% after 60s disintegration. Internal cracks of the sample are transformed into complex connected cracks, and there are many large pores formed by erosion and presented as complex geometry shape. The geometry of cracks is analyzed from three aspects: width, length and bending ratio. It is found that cracks have strong linear characteristics after 60s disintegration, which may be related to the initial rapid infiltration damage.

Developing a robust, porous and biodegradable scaffold remains a significant challenge in bone tissue engineering. For this purpose, biodegradable and porous hydrogel has been researched for many years. However, it is still a big challenge to get a porous and robust hydrogel in a one-step method. The objective of this study is to prepare a porous hydrogel with a triple network using chitosan and alginate cross-linked by genipin and Ca2+ respectively and a simple foaming method was utilized to enrich porous structures. Besides, the optimum dosage of foaming agents and surfactant agents is studied to prepare a porous hydrogel with suitable pore size and high mechanical strength. Furthermore, the morphology, percentage porosity, swelling property, degradation profile and biocompatibility of the porous chitosan-alginate (CA) hydrogel has been assessed. The results show that the porous hydrogel prepared in this paper has pores with size of 45–280 ​μm and 91.16% porosity. The synthesis of triple network structure makes this hydrogel tough, and the wall stiffness of the dry porous CA hydrogel is 7.05 ​± ​0.084 ​MPa. The excellent biodegradability of chitosan and alginate makes the prepared hydrogel have good biodegradability and low cytotoxicity. These properties attest that this hydrogel might be an ideal candidate for tissue engineering.

The meso-deformation evolution in grus is crucial to the mechanical characteristics. Although the macroscopic deformation of grus has been widely studied, its physical meso-scale deformation and shear band evolution have not been well understood. In this paper, high energy X-ray computed tomography (CT) measurements and digital volume correlation (DVC) were performed on a grus sample under triaxial compression in order to quantify shear strain and shear bands in grus. Besides, a series of three-dimensional octahedral shear strain was obtained by DVC analysis. Furthermore, the corresponding evolution of the shear band, content, distribution characteristics and connectivity were investigated. The results show that the shear bands are formed at the stage where the axial strain is equal to 8%; generally, they are obliquely distributed as a whole and connected in an irregular flat strip shape; besides, the failure path may cause the grains to divert or branch due to the anisotropic distribution of grains. Moreover, the octahedral shear strain approximation obeys the χ2 distribution. There are at least two types of distribution of shear bands. Small-scale shear bands may be generated in different areas in the material at the initiation state, whereas the correlation and directionality between the variety of shear bands are slight; while at the shear failure stage and the subsequent stages, a close correlation is found between the shear bands, the direction consistency is significant.

Background The role of the chemokine axis, CX3CL1/CX3CR1, in the development of cardiovascular diseases has been widely speculated. Angiotensin II (Ang II) is a pivotal factor promoting cardiovascular complications in patients with chronic kidney disease (CKD). Whether there is a link between the two in CKD remains unclear. Methods The uremic mice were treated with losartan for 8 weeks, and the expression of aortic CX3CL1/CX3CR1 was detected. Cultured mouse aortic vascular smooth muscle cells (VSMCs) were stimulated with Ang II, and then CX3CR1 expression was assessed by western blot. After the targeted disruption of CX3CR1 by transfection with siRNA, the migration of VSMCs was detected by transwell assay. Finally, both the activation of Akt pathway and the expression of IL-6 were detected by western blot. Results Losartan treatment reduced the upregulation of aortic CX3CL1/CX3CR1 expression in uremic mice. In vitro, Ang II significantly upregulated CX3CR1 expression in VSMCs. Targeted disruption of CX3CR1 attenuated Ang II-induced migration of VSMCs. In addition, the use of CX3CR1-siRNA suppressed Akt phosphorylation and IL-6 production in VSMCs stimulated by Ang II. Conclusions The aortic CX3CL1/CX3CR1 is upregulated by Ang II in CKD, and it contributes to Ang II-induced migration of VSMCs in vitro.

a water treatment agent for white pulp of pomelo peel was developed using commercial Pomelo as raw material, which laid a foundation for the further development and utilization of Pomelo Peel. Indeed adsorption Cu2+, Fe3+ as an index, the effect of modification on the basis of single factor experiment research on the use of sodium hydroxide concentration, pH, adsorbent, adsorption process the time required to the influence of factors such as the adsorption effect, orthogonal experiment as the main experimental method to determine the modification of pomelo peel white pulp desorption process using the adsorption effect of again. The results showed that the modified water treatment agent had higher adsorption efficiency for Cu2+ and Fe3+ in water, and had favourable reabsorption ability, it can be reused and has higher adsorption efficiency. The developed water treatment agent for white pulp of Pomelo Peel has laid a foundation for the adsorption of Cu2+ and Fe3+ in water, the efficient utilization of white pulp of pomelo peel and the invention of production equipment.

In recent years, perovskite solar cells have been developed rapidly because of its excellent crystalline properties, high optical absorption coefficient, high carrier mobility, long carrier life and direct band gap, and suitable to be used as light absorbing layer material of photovoltaic devices. However, the most prominent problem of perovskite materials is that a lot of organic cations will migrate and lose in the process of illumination or heating, which is considered to be the main reason for the performance degradation of perovskite films and devices. Therefore, the suppression of ion migration in perovskite is helpful to improve the stability of perovskite materials and devices and enhance their photoelectric properties. In order to effectively control the ion migration in perovskite films, this paper uses the cation-π supramolecular interaction, to prepare the perovskite films with better photoelectric performance and higher stability. The experimental results show that the photoelectric conversion efficiency of the perovskite solar cellsdevice doped with rubrene is increased from 18.60% to 20.86%, and the hysteresis of the cell is also significantly suppressed.

Angiotensin II (Ang II) dysregulation has been determined in many diseases. The CX3CL1/CX3CR1 axis, which has a key role in cardiovascular diseases, is involved in the proliferation and inflammatory cytokine production of vascular smooth muscle cells (VSMCs). In this study, we aim to explore whether Ang II has a role in the expression of CX3CL1/CX3CR1, thus contributing to the proliferation and pro-inflammatory status of VSMCs. Cultured mouse aortic VSMCs were stimulated with 100 nmol/L of Ang II, and the expression of CX3CR1 was assessed by western blot. The results demonstrated that Ang II significantly up-regulated CX3CR1 expression in VSMCs and induced the production of reactive oxygen species (ROS) and the phosphorylation of p38 MAPK. Inhibitors of NADPH oxidase, ROS, and AT1 receptor significantly reduced Ang II-induced CX3CR1 expression. Targeted disruption of CX3CR1 by transfection with siRNA significantly attenuated Ang II-induced VSMC proliferation as well as down-regulated the expression of proliferating cell nuclear antigen (PCNA). Furthermore, CX3CR1-siRNA suppressed the effect of Ang II on stimulating Akt phosphorylation. Besides, the use of CX3CR1-siRNA decreased inflammatory cytokine production induced by Ang II treatment. Our results indicate that Ang II up-regulates CX3CR1 expression in VSMCs via NADPH oxidase/ROS/p38 MAPK pathway and that CX3CL1/CX3CR1 axis contributes to the proliferative and pro-inflammatory effects of Ang II in VSMCs.

The miniature penetrometer tests are often used to investigate the distribution and strength of aggregates in soils. In this work, the elastoplastic solution to spherical cavity expansion for stress distribution in saturated clay is studied using the cavity expansion theory in combination with the modified Cambridge clay (MCC) model. From the case study, it can be found that the radial stress, circumferential stress and tip resistance increased when the modulus of compression increased. The radial stress increased nonlinearly when the critical stress ratio increased. However, the relationship between circumferential stress, tip resistance and critical stress ratio showed linear growth properties. When the penetration probe diameters are in the range of 1.75 to 2.95 mm, theoretical values are smaller than test data, and all the deviations between theoretical and test values are within 5%. Therefore, results indicate the elastoplastic solution can be used to predict the tip resistance and penetration stress.