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Topological superconductors (TSCs) are an exotic field due to the existence of Majorana zero-modes (MZM) that obey non-Abelian statistics and can be used to implement topological quantum computations.

To investigate the effects of nitroquine on the development of different stages ofFollowing exposure to nitroquine-containing sucrose water one day prior toNitroquine treatment exhibits diverse effects the development of different stages of

On October, 2021, the WHO announced the recommendation of RTS, S/AS01 for use among children living in moderately and highly malaria-endemic areas, which receives global attention. Here, the history of RTS, S/AS01 vaccine development and its role in malaria control are described.

The apoptosis of vascular endothelial cells (VEC) is related to ischemic stroke. Phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT/PKB) signaling pathway can upregulate Bcl-2 expression, reduce reactive oxygen species (ROS) production, and induce apoptosis. The level of miR-124 was significantly increased after cerebral ischemia. This study aimed to investigate the role of miR-124 in regulating PI3K expression, brain VEC apoptosis, and ROS production.The expressions of miR-124, PI3K, p-AKT, and Bcl-2 in brain VEC of rats from the sham group and middle cerebral artery occlusion (MCAO) group were tested. Bioinformatics analysis showed the complementary binding site between miR-124 and PI3K mRNA. ROS content and cell apoptosis were detected by flow cytometry. Rat brain VEC were cultured in vitro and treated by oxygen-glucose deprivation (OGD) for 6 h. VECs were divided into four groups, including miR-NC, miR-124 inhibitor, pIRES2-blank, and pIRES2-PI3K groups, and were further treated by OGD.MiR-124 expression, ROS content, and cell apoptosis were markedly increased, whereas the levels of PI3K, p-AKT, and Bcl-2 were markedly reduced in rat VECs from MCAO group compared with that in the sham group. OGD treatment significantly induced VECs apoptosis, upregulated miR-124 expression and ROS content, and down-regulated the levels of PI3K, p-AKT, and Bcl-2. MiR-124 inhibitor or transfection of pIRES2-PI3K plasmid apparently enhanced PI3K, p-AKT, and Bcl-2 expressions, alleviated cell apoptosis and decreased ROS content in VECs induced by OGD.Our data demonstrated that miR-124 induced the apoptosis of brain vascular endothelial cells via the down-regulation of PI3K/AKT signaling pathway and promotion of ROS production.

Dacite is the dam site material of Rumei Hydropower Station, Tibet, China. To study the deformation and failure mechanisms of dacite under loading and unloading conditions, a series of triaxial compression tests and unloading confining pressure tests were carried out. Experimental results indicate that the deformation and strength behaviour of dacite are different between loading and unloading conditions. The lateral strain is more sensitive to the decreasing of the confining pressure under unloading process. In a uniaxial compression test, the sample is axial splitting. Shear failure takes place under the confining pressure. However, the samples failed with combined shear and tensile fractures in unloading confining pressure tests. From the viewpoint of energy conversion, the failure of dacite in triaxial compression process is determined by the released elastic strain energy, while the dissipated strain energy plays a major role in unloading confining pressure process.

High-performance ultraviolet (UV) detectors with both high responses and fast speeds are hard to make on homogeneous crystal semiconductor materials. Here, the UV response characteristics of mixed-phase MgZnO thin films with different internal structure distributions are studied. The mixed-phase MgZnO-based detector with the given crystal composition has a high response at both deep UV light (96 A W

Many findings have demonstrated long noncoding RNAs (lncRNAs) as crucial regulatory molecules in the progression of osteosarcoma. The aim of this study was to explore the roles and mechanisms of LncRNA LINC00689 (LINC00689) in osteosarcoma.Differential levels of LINC00689 and miR-655 in osteosarcoma samples and cell lines were analyzed by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The associations between LINC00689 expression and prognostic significance of osteosarcoma patients were analyzed using a series of statistical assays. Loss-of-function and gain-of-function assays were performed to investigate the role of LINC00689 in proliferation and metastasis in vitro. Bioinformatic assays, Luciferase report assays, and rescue assays were applied to illustrate the ceRNA mechanism network of LINC00689/miR-655/SOX18.We found that LINC00689 expression was distinctly upregulated in osteosarcoma specimens and cell lines. MiR-655 displayed a trend of remarkably decreased expression in osteosarcoma tissues. In addition, we showed that LINC00689 could specifically interact with the promoter of SP1 and activate LINC00689 transcription. Further clinical studies indicated that higher levels of LINC00689 were associated with advanced clinical stage, positively distant metastasis, and unfavorable clinical outcome. Functional studies revealed that the knockdown of LINC00689 suppressed the proliferation, migration, and invasion of osteosarcoma cells, and promoted apoptosis. Final mechanistic investigations confirmed that upregulation of LINC00689 competitively bound to miR-655 that prevented SOX18 from miRNA-mediated degradation, thus facilitating osteosarcoma progression.All our findings suggested that SP1-induced upregulation of LINC00689 promoted osteosarcoma progression by regulating miR-655/ SOX18 axis, which provided a novel insight for osteosarcoma tumorigenesis.

Odorant binding proteins (OBPs) and chemosensory proteins (CSPs) play essential roles in insect chemosensory recognition. Here, we identified nine OBPs and nine CSPs from the Myzus persicae transcriptome and genome. Genomic structure analysis showed that the number and length of the introns are much higher, and this appears to be a unique feature of aphid OBP genes. Three M. persicae OBP genes (OBP3/7/8) as well as CSP1/4/6, CSP2/9 and CSP5/8 are tandem arrayed in the genome. Phylogenetic analyses of five different aphid species suggest that aphid OBPs and CSPs are conserved in single copy across all aphids (with occasional losses), indicating that each OBP and CSP class evolved from a single gene in the common ancestor of aphids without subsequent duplication. Motif pattern analysis revealed that aphid OBP and CSP motifs are highly conserved, and this could suggest the conserved functions of aphid OBPs and CSPs. Three OBPs (MperOBP6/7/10) are expressed antennae specifically, and five OBPs (MperOBP2/4/5/8/9) are expressed antennae enriched, consistent with their putative olfactory roles. M. persicae CSPs showed much broader expression profiles in nonsensory organs than OBPs. None of the nine MperCSPs were found to be antennae specific, but five of them (MperCSP1/2/4/5/6) showed higher expression levels in the legs than in other tissues. MperCSP10 mainly expressed in the antennae and legs. The broad and diverse expression patterns of M. persicae CSPs suggest their multifunctions in olfactory perception, development and other processes.

A random generation method of periodic mesostructures of soil-rock mixtures based on random polygon is proposed and used in the generation of an RVE model. A code for generating a periodic mesh and periodic boundary is developed for the numerical simulation. Macroscopic elastic parameters of the SRMs are calculated based on the simulation using numerical homogenization. The elastic modulus shows a size effect, namely, the modulus deceases gradually with an increase in the model size. The border effect is related to the model size and is large in small-sized models. Rock aggregates arranged in a certain direction induce property anisotropy.

The permeability and porosity of a porous sandstone under cyclic loading–unloading conditions are measured using an integrated permeability and porosity measurement system. Mineral content analysis of the rock is performed. The rock contains open microcracks and pores, which can be closed after cyclic loading–unloading; as a result, the permeability and porosity decrease. Based on the test results, the empirical relations of confining stress-dependent sandstone permeability and porosity are derived. A power law is suggested to describe the relationship between the stress-dependent porosity and permeability of the sandstone under both loading and unloading conditions within the stress range used in the experiment. The permeability of the sandstone is more sensitive to stress than to porosity. It is inferred from the test results that the evolution of sandstone porosity and permeability is related to the relative movement of particles and the closure of microcracks.

Because of the complex geological structure, determination of the field mechanical parameters of the columnar jointed rock mass (CJRM) was a challenging task in the design and construction of the Baihetan hydropower plant. To model the mechanical behaviour of the CJRM, uniaxial compression tests were conducted on artificial CJRM specimens with geological structure similar to that found in the actual CJRM. Based on the test results, the anisotropic deformation and strength were mainly analysed. The empirical correlations of evaluating the field mechanical parameters were derived based on the joint factor approach and the modulus reduction factor method. The findings of the physical model tests were then used to estimate the field moduli and unconfined compressive strengths of the Baihetan CJRM. The results predicted by physical model tests were compared with those obtained from the field tests and the RMR classification system. It is concluded that physical model tests were capable of providing valuable estimations on the field mechanical parameters of the CJRM.

Due to the intensive rainfalls in October 2008 and the heavy snowfalls in February 2009, the Zhenggang deposit exhibited a high probability of landslide reactivation. A good understanding in landslide run-out prediction and failure mechanism analysis was thus highly urgent. In this study, the landslide dynamic simulations were performed for studying the run-out prediction and the failure mechanism of the Zhenggang deposit. The impacts of the friction coefficient at sliding surface and the contact damping ratio on landslide run-out were investigated. The potential improvement of the proposed landslide run-out modeling was discussed.

Recently, long noncoding RNAs (lncRNAs) have attracted much attention for their roles in tumor progression. The aim of this study was to investigate the exact role of lncRNA OR3A4 in the development of ovarian cancer (OC), and to explore the possible underlying mechanism.OR3A4 expression in OC tissue samples was detected by Real-time quantitative polymerase chain reaction (qRT-PCR). Moreover, wound healing assay and transwell assay were performed to evaluate the effect of OR3A4 on the metastasis of OC. Furthermore, the underlying mechanism was explored by RT-qPCR and Western blot assay.The expression level of OR3A4 in OC samples was significantly higher than that of adjacent tissues. Moreover, cell migration and invasion were significantly repressed after OR3A4 knockdown in vitro. Moreover, the mRNA and protein expressions of kruppel-like factor 6 (KLF6) were remarkably upregulated after knockdown of OR3A4. Furthermore, the expression level of KLF6 was negatively correlated with the expression of OR3A4 in OC tissues.Our results showed that OR3A4 could enhance OC cell metastasis and invasion via suppressing KLF6. Moreover, OR3A4 might be a potential therapeutic target for OC.

In this work, the Al/GO/Si/Al RRAM device was fabricated with solution-processed graphene oxide (GO) thin film at low temperature (50 □). A superior electrical performance and stable operation of the device has been achieved showing typical bipolar resistive switching characteristics with operation voltage lower than 3 V, retention property sustained over 104 s and endurance over 102 cycles. The results suggest that the solution-processed GO thin films exhibit great potential for use in the flexible device.

Permeability is an important factor for seepage analysis of rock material, and a key factor in ensuring the safety of underground works. In this study, the permeability evolution of granite gneiss during triaxial creep tests was investigated. In the context of an underground oil storage cavern in China, a series of hydro-mechanical coupling creep tests were conducted on rock cores of granite gneiss at three different pore pressures to reveal the effect of pore pressure on the permeability evolution and to investigate the correlation between the permeability and volumetric strain during the creep process. During the creep tests, the permeability decreases in the initial loading phase. At all deviatoric stress levels, the permeability remains stable in the steady creep stage and increases rapidly in the accelerated creep stage. Based on the test data, the initial permeability, steady permeability and peak permeability at various stress levels are defined. The effect of pore pressure on the permeability is captured by a linear model. In addition, the relationship between permeability and volumetric strain can be described as a process divided into three phases, with different functions in each phase.

This study develops a coupled elastoplastic damage model for brittle rocks within the framework of irreversible thermodynamics. In the model, degradations in the deformation and strength of rocks induced by damage are considered in the elastic stiffness matrix and plastic yield criterion. The thermodynamic force associated with damage is expressed as a state function of elastic strain and the internal plastic variable. The damage potential and criterion, as functions of the thermodynamic force, are constructed to describe the damage evolution of rocks, and to determine whether they are damaged, respectively. Constitutive relationships, and their numerical formulations of a return mapping algorithm for finite element method implementation, are deduced under three different loading conditions: damage, plastic and coupled plastic damage. For engineering application, the developed model is implemented in the finite element programme Abaqus as a user-defined material model (UMAT). The coupled model is then used for simulating the re-distributed stress fields, displacement and EDZs of the sidewall rock mass around the underground powerhouse of the Wudongde hydropower plant.

In order to understand the mechanical behaviours of the surrounding rocks in the underground caverns of the Wudongde hydropower plant, triaxial tests are performed on a type of dolomite. It is revealed that damage induced by crack development is the main factor controlling the nonlinear plastic deformation and failure behaviour of the dolomite in both pre- and post-peak regimes. Based on this understanding, a coupled elastoplastic damage model is developed for capturing the dolomite’s mechanical behaviours. In the model, the effects of plasticity and damage on rocks is described by introducing plastic hardening and damage softening commonly in the plastic yield surface. Which are both derived from a suitable Helmholtz free energy function. The model is used to simulate the triaxial tests. Comparisons between test results and the numerical modelling show that the developed model is capable of describing the macro mechanical behaviours of the Wudongde dolomite.

To mitigate the degradation of radiation characteristics for large ground-reflector antennas due to dielectric radomes, a simple compensation strategy based on phase modification has been proposed. A modification of the phase distribution in the original aperture of an enclosed reflector antenna via moving the feed or subreflector along axial direction opportunely could compensate the phase shift caused by dielectric radome, minimize the phase difference in transmission aperture, and reduce the distortion of the antenna’s far-field pattern. The movement of the subreflector could be calculated by a formula, which has been provided in this work based on geometrical optics (GO). Good compensated results are obtained in a 9.14-m one-piece dielectric sandwich radome. The proposed compensation strategy could also be applied to metal-space frame radome; a 20-m radome is presented to verify the results .

A micromechanics-based plastic damage model including localised failure is proposed in the present work for heterogenous materials which can be treated as a porous matrix reinforced by mineral inclusions. This model explicitly considers the influences of pores and inclusions volume fractions, also the solid phase dilatancy on the overall mechanical performance. The induced damage in solid phase is also considered. Based on this two-scale model, the bifurcation analysis is performed to detect both the onset and orientation of localization band. Numerical simulations are carried out for different cases. It is found that the material’s microstructure affects importantly the onset point of the localization and the post-localization behavior. As an example of validation, the proposed model enhanced with localization analysis is then adopted to predict the overall mechanical response before and post localization of this typical claystone. Comparing with the experimental results, the capacity of this enhanced modelling is clearly demonstrated.

Asphalt is a temperature sensitive material, distribution characteristics and vary rules of asphalt pavement temperature have an important impact on the bearing capacity and performance of pavement, which is a concern of domestic and foreign researchers. The objective of this study was to explore the correlation between pavement temperature of asphalt pavements and meteorological factors and implement an accurate trend prediction of the asphalt pavement temperature. First, errors and missing data in the meteorological dataset were cleaned. Then, the three kinds of temperature prediction models of asphalt pavements in winter were established by Gradient Boosting Decision Tree (GBDT), Random Forest (RF) and Linear Regression (LR). The results indicate that GBDT would perform an excellent ability on prediction. The mean-square-error of the GBDT predicting results has a lower value of 1.5 when compared with the Random Forest and Linear Regression owing to the high robustness and the good generalization ability, which reflects the GBDT model has a good applicability in the field of prediction. The research would serve as a technical support for the machine learning algorithms applied in the field of the application of prediction problems.

Asphalt is a typical temperature-sensitive material. In order to explore the correlation between surface temperature of asphalt pavements and meteorological factors, the association rules mining algorithm (Apriori) was applied to identify the key factors affecting the surface temperature of asphalt pavement. Firstly, errors and missing data in the meteorological dataset were cleaned. Then, Apriori was applied to identify the key factors affecting the asphalt pavement temperature. The results indicate that Apriori would perform an excellent ability to analyze the correlation rules between meteorological factors with the minimum confidence of 0.8 and the key meteorological factors which affect the temperature change of asphalt pavements are excavated including air temperature, air pressure, dew point temperature and relative humidity. The research would serve as a technical support for the machine learning algorithms applied in the field of the association rule analysis.

A novel hierarchical multiscale strength reduction method with a coupled finite element method (FEM) and discrete element method (DEM) approach is proposed for a heterogeneous slope. This approach is implemented and validated by employing a soil and rock mixture (SRM) slope. Compared with conventional strength reduction method, this method avoids the expensive cost of large field tests in parameters estimation and provides a better understanding of the failure mechanism with macroscopic and microscopic results. The multiscale simulation approach, which is directly based on particle-level simulation and bypasses conventional constitutive assumptions, provides a novel numerical tool for slope stability analysis of heterogeneous geomaterials.

A novel robust method for estimating equivalent tunnelling Mohr–Coulomb strength parameters in elastic–plastic or elasto–brittle–plastic media satisfying Hoek–Brown failure criterion is proposed. Based on the best uniform approximation technique, this method consists of explicit and closed-form formulae in terms of elementary functions, making the estimation of equivalent parameters more convenient than other methods. A simple code is provided and a series of benchmark test cases are performed for validation. When the tunnel support is accurately known, the performance estimates of this method are better than estimates of best fitting in an artificial stress range and best fitting in the existing range methods, but not as accurate as the performance of equating model responses method and that proposed by Jimenez et al. However, when the estimation of support pressure is poor, this method is the most robust among all methods. In elasto–brittle–plastic rock mass, the advantage of robustness of this method i...

Baitieba landslide, located on the left bank of Xiluodu reservoir, is an ancient landslide. The landslide slides along the shallow and deep sliding surfaces after excavation. Sliding along the shallow sliding surface has become stabilised by and large; whereas sliding along the deep sliding surface still continues after some effective and systematic treatments. Based on the data of inclinometer boreholes observed in the field, a detailed investigation into the mechanism of continuous sliding along the deep sliding surface is carried out. It is found that slow creep of the ancient sliding zone is a predominant factor, and its creep deformation has undergone two stages: attenuation of creep deformation and linear increase of creep deformation. A numerical simulation, considering creep behaviour of the ancient slip zone, is also conducted to verify the mechanism of movement of the landslide inferred from the monitoring data of inclinometer boreholes. Using the monitoring data, long-term stability of the land...

Landslides are one of the major natural disasters that are frequently occurring in southwestern China. The main objective of this study is to investigate the relationship between failure of landslide and fractal dimension using displacement time-series. Taking two slopes in southwestern China as examples, we estimate the fractal parameters of displacement time-series and analyze the relationship between fractal dimension and the stability of the slope during the evolution of landslides. The result shows that the fractal dimension increases when a landslide undergoes a transition from stability to failure, but decreases during the evolution from active to stable. Fractal dimension has a critical value of 1.10 in the transition between active and stable, which indicates that fractal dimension is an important nonlinear parameter in the evaluation of the stability of landslides, although more studies and in situ data are required for validation.