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Seizures are a frequent symptom of unruptured brain arteriovenous malformations (bAVMs). However, the brain regions responsible for these seizures remain unclear. To identify the brain regions causally involved in bAVM-related seizures, we retrospectively reviewed 220 patients with unruptured bAVMs. Using voxel-based lesion-symptom mapping (VLSM) analyses, we tested whether individual brain regions were associated with unruptured bAVM-related seizures. The result revealed that unruptured bAVMs causing seizures are anatomically heterogeneous at the voxel level. Subsequently, lesion network mapping (LNM) analyses was performed to determine whether bAVMs causing seizures belonged to a distributed brain network. LNM analyses indicated that these lesions were located in a functional network characterized by connectivity to the left caudate and precuneus. Moreover, the discrimination performance of the identified seizure network was evaluated in discovery set by calculating the individualized network damage score and was tested in validation set. Based on the calculated network damage scores, patients were divided into low-, medium-, and high-risk groups. The prevalence of seizures significantly differed among the three risk categories in both discovery (p = .003) and validation set (p = .004). Finally, we calculated the percentage of voxels in the canonical resting-state networks that overlapped with the seizure-susceptible brain regions to investigate the involvement of resting-state networks. With an involvement percentage over 50%, the frontoparietal control (82.9%), limbic function (76.7%), and default mode network (69.3%) were considered to be impacted in bAVM-related seizures. Our study identified the seizure-susceptible brain regions for unruptured bAVMs, which could be a plausible neuroimaging biomarker in predicting possible seizures.

Supersonic boundary layer transition induced by a streamwise vortex is experimentally investigated based on the nanoparticle-based planar laser scattering technology, with an inflow Mach number of 2.7 and a unit Reynolds number of 8.79 × 106 m−1. Though the vortex is outside the boundary layer, it results in obvious difference of transition position along spanwise direction. On the up-wash side, transition to turbulence is completed in advance compared to the vortex-free case, and transition position moves more upstream as the vortex approaches the wall. Conversely, the transition process on down-wash side is inhibited. The promotion and inhibition effects on transition are found to be induced by the influence of vortex on streak density.

Structural characteristics of the strong interaction between an oblique shock wave and streamwise vortex are experimentally investigated based on the nanoparticle-based planar laser scattering technology. Fine structures of reorganized vortices and helical structures are first recorded in experimental visualization. For the case with the strongest shock wave, a catastrophe process occurs due to the change of breakdown type, which gives birth to abundant small-scale vortical structures. Fractal and feature analyses indicate that the turbulent mixing dramatically increases after the interaction, especially for the case with spiral breakdown.

In this paper, we study the following Schrödinger–Kirchhoff-type problem: [Formula: see text], [Formula: see text], where a > 0 and b > 0 are small enough. Under suitable assumptions on f, we obtain the existence of ground state sign-changing solution u b by the constraint variational method with Miranda’s theorem. Moreover, we prove that its energy is strictly larger than twice that of the ground state solution.

Bolboschoenus planiculmis is a typical wetland sedge with both ecological and agricultural value. We report the first complete chloroplast genome sequence of this species. The total genome size is 186,539 bp, containing a large single-copy region (LSC) of 104,654 bp, a small single copy region (SSC) of 9,659 bp and two inverted repeats (IRs) of 36,113 bp by each. The GC content is 33.59%. The genome encodes 105 unique genes, including 71 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis shows this species has a strong sister relationship with Cyperus. Our work could be helpful in understanding the evolution of Cyperaceae.

We use the Reynolds-averaged Navier–Stokes (RANS) equations with a full Reynolds stress model (RSM) to study the effect of the corner angle in supersonic corner flow. RANS data are compared to reference direct numerical simulation of fully developed a square duct flow, which support predictive capability of secondary flows from Stress-ω RSM. We then carry out a parametric study by changing the corner angle in the range θ = 45 °– 135 °, focusing on the effect on the mean streamwise and secondary flow. The maximum strength of the secondary flows of about 0.015 u ∞ occurs for θ = 90 °, which is similar to what is found in fully developed square ducts. Secondary eddies have approximately unit aspect ratio, and they maintain their shape for different corner angles by translating in the direction parallel to the closest wall. As a result, the position of the vortex center can be described by a simple geometrical transformation of the wall-parallel coordinate. We find that small corner angles are responsible for locally relaminarization flow at the corner, but otherwise the mean streamwise velocity profiles transformed according to van Driest following the canonical law-of-the-wall.

Vehicle routing and path planning become more challenging underwater where visibility is limited, and landscape variations are more significant. The search for optimal paths can be complicated further by uncertain environments such as water flow and unknown geographical features. This chapter describes the characteristics of underwater navigation, reviews the main problems of underwater navigation and common path planning methods. Then, the firefly algorithm is used to solve the path planning problem, and the algorithm is improved according to the characteristics of underwater path planning. Finally, aiming at different underwater navigation scenes, the application effects of the improved firefly algorithm are compared and analyzed.

The development of navigation technology stems from the need for direction and location identification of military and production activities in the early stages of human society. With the advancement of society and the improvement of productivity, the space for human activities has been expanding, which requires higher technical for navigation. Navigation under uncertainty is a challenging problem. When dealing with navigation problems in the case of complex dynamic environment information, intelligent revelation from nature can often play a very good role. This chapter briefly introduces the generation and definition of navigation and reviews the development history of navigation. Then, expound the basic concepts of natural heuristic navigation algorithms including ecosystem simulation algorithm, swarm intelligence algorithm, evolutionary algorithm, and artificial intelligence algorithm, and the principle and characteristics of the algorithm are summarized. Finally, prospect the development of the natural heuristic navigation algorithm and introduce its main application areas.

Fin-generated swept shock wave/turbulent boundary layer interactions were experimentally investigated via nanoparticle-based planar laser scattering method, surface oil flow visualizations, surface pressure measurements, and particle image velocimetry. Surface plateau pressure is also theoretically predicted. The plateau pressure of present quasi-conical swept shock interaction is dependent on the local skin friction coefficient and normal Mach number component, and can be predicted per a criterion deduced from free interaction theory. Visualizations and surface pressure measurements confirm that the surface plateau pressure data are equal to the pressure downstream of the separation shock; the upstream influence line is parallel to the impingement line of the separation shock on the flat plate. These observations support the free interaction theory as-applied to quasi-conical swept shock interactions.

By employing a nanoparticle-based planar laser scattering technique, with inflow Mach number of 2.95, boundary layers formed over two concave walls with respective curvature radii of 113 and 908 mm are visualized. The formation and the breakup process of the Gortler vortices have been clearly captured, which has seldom been done before under the supersonic condition. Different from the incompressible case, the breakup of the Gortler vortices in the supersonic boundary layer is found to be mainly attributed to the varicose mode instability. The Gortler vortices are not stationary, instead they are moving in the spanwise direction.

EZH2, a histone H3 lysine‐27‐specific methyltransferase, is involved in diverse physiological and pathological processes including cell proliferation and differentiation. However, the role of EZH2 in liver fibrosis is largely unknown. In this study, it was identified that EZH2 promoted Wnt pathway‐stimulated fibroblasts in vitro and in vivo by repressing Dkk‐1, which is a Wnt pathway antagonist. The expression of EZH2 was increased in CCl4‐induced rat liver and primary HSCs as well as TGF‐β1‐treated HSC‐T6, whereas the expression of Dkk1 was reduced. Silencing of EZH2 prevented TGF‐β1‐induced proliferation of HSC‐T6 cells and the expression of α‐SMA. In addition, knockdown of Dkk1 promoted TGF‐β1‐induced activation of HSCs. Moreover, silencing of EZH2 could restore the repression of Dkk‐1 through trimethylation of H3K27me3 in TGF‐β1‐treated HSC‐T6 cells. Interestingly, inhibition of EZH2 had almost no effect on the activation of HSC when Dkk1 was silenced. Collectively, EZH2‐mediated repression of Dkk1 promotes the activation of Wnt/β‐catenin pathway, which is an essential event for HSC activation.

BACKGROUND The aim of this study was to investigate the correlation between Hector Battifora mesothelial-1 (HBME-1) expression and the clinical pathological characteristics and prognosis of osteosarcoma (OS). MATERIAL AND METHODS HBME-1 expression was assessed using immunohistochemistry in OS tissues (n=152), osteochondroma tissues (n=91), and normal bone tissues (n=74). We carried out a follow-up lasting 8-60 months to investigate HBME-1 expression and its correlations with the clinical pathological characteristics and prognosis of OS. RESULTS HBME-1 was highly expressed in OS tissues compared with osteochondroma tissues and normal bone tissues, and was highly expressed in osteochondroma tissues compared with normal bone tissues (all P

Understanding the responses of stomatal structure, photosynthesis and biomass of maize to exogenous Ca探讨盐胁迫下玉米气孔特征、光合作用和生物量对外源钙离子的响应,有助于深入理解添加外源钙离子(Ca

Direct numerical simulation is conducted to uncover the response of a supersonic turbulent boundary layer to streamwise concave curvature and the related physical mechanisms at a Mach number of 2.95. Streamwise variations of mean flow properties, turbulence statistics and turbulent structures are analysed. A method to define the boundary layer thickness based on the principal strain rate is proposed, which is applicable for boundary layers subjected to wall-normal pressure and velocity gradients. While the wall friction grows with the wall turning, the friction velocity decreases. A logarithmic region with constant slope exists in the concave boundary layer. However, with smaller slope, it is located lower than that of the flat boundary layer. Streamwise varying trends of the velocity and the principal strain rate within different wall-normal regions are different. The turbulence level is promoted by the concave curvature. Due to the increased turbulence generation in the outer layer, secondary bumps are noted in the profiles of streamwise and spanwise turbulence intensity. Peak positions in profiles of wall-normal turbulence intensity and Reynolds shear stress are pushed outward because of the same reason. Attributed to the Görtler instability, the streamwise extended vortices within the hairpin packets are intensified and more vortices are generated. Through accumulations of these vortices with a similar sense of rotation, large-scale streamwise roll cells are formed. Originated from the very large-scale motions and by promoting the ejection, sweep and spanwise events, the formation of large-scale streamwise roll cells is the physical cause of the alterations of the mean properties and turbulence statistics. The roll cells further give rise to the vortex generation. The large number of hairpin vortices formed in the near-wall region lead to the improved wall-normal correlation of turbulence in the concave boundary layer.

The structural properties and the phase transition for scandium carbide (ScC) have been studied in NaCl (B1), CsCl (B2), ZB (B3), WZ (B4), NiAs (B81), WC (B h ), and Pmmn structures by using the pseudopotential plane-wave method in the framework of the density functional theory. Our theoretical results show that the most stable structure is the B1 phase, contrary to the result of Rahim et al. The phase transitions B1 → Pmmn and Pmmn → B2 are predicted at 83.7 and 109.7 GPa, respectively. At the same time, we find that the B3, B4, B81, and B h phases are not stable over the whole pressure range considered. In particular, the elastic constants of Pmmn-ScC under high pressure are obtained successfully. The effects of pressure on the elastic properties of B1-ScC and Pmmn-ScC are also predicted. The Debye temperatures Θ and the sound velocities of these two structures are estimated from the elastic constants, and by analyzing G/B, the brittle-ductile behavior of ScC is assessed. In addition, the density of states of B1-ScC at high pressures is also discussed.

Alcoholic liver disease (ALD) is a complex process that includes a wide range of hepatic lesions, from steatosis to cirrhosis, and even hepatocellular carcinoma (HCC). Accumulating evidence shows that the cytotoxic effects of ethanol metabolism lead to cell apoptosis and necrosis in ALD. Recently, several studies revealed that multifunctional protein β-arrestin 2 (Arrb2) modulated cell apoptosis in liver fibrosis and HCC, but its role in ALD has not been fully understood. The aim of this study is to explore the function and underlying mechanism of Arrb2 in hepatocyte survival and apoptosis in ALD. In our study, the primary hepatocytes were isolated from the livers of C57BL/6 mice fed EtOH-containing diet, it showed an increased level of Arrb2. EtOH also significantly up-regulated Arrb2 production in AML-12 cells in vitro. Furthermore, TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) and FCM results demonstrated that knockdown of Arrb2 could inhibit hepatocyte apoptosis induced by EtOH in vivo and vitro while over-expression of Arrb2 induced apoptosis in ALD. In addition, western blot results revealed that Arrb2 remarkably suppressed the Akt signaling. Taken together, our data suggested that Arrb2 may serve as a potential therapeutic target for ALD by promoting hepatocyte apoptosis via Akt suppression.

ABSTRAT Alcoholic liver disease (ALD) and its complication continued to be a major health problem throughout the world. Increasing evidence suggests that microRNA (miRNA) that regulate apoptosis, inflammation and lipid metabolism are affected by alcohol in ALD. MiR-200a has emerged as a major regulator in several liver diseases, but its role in ALD has not been elucidated. The aim of this study is to figure out the biological function of miR-200a in ALD and to explore its underlying mechanism. The expression pattern of miR-200a were analyzed in vitro and in vivo, we showed that miR-200a was up-regulated in ALD in AML-12 and primary hepatocyte. We then examined it's effect on cell apoptosis and identified zinc finger E-box binding homeobox 2 (ZEB2; also known as SIP1) as a direct target gene of miR-200a. Furthermore, reintroduction of ZEB2 could reverse the pro-apoptosis of miR-200a on AML-12. Taken together, our study demonstrated that miR-200a regulates the apoptosis of hepatocyte in ALD by directly target ZEB2, both of which could serve as new therapeutic targets for ALD.

The pressure-induced structural phase transition of rhenium monocarbon (ReC) is investigated via the projector augmented wave (PAW) method with the generalized gradient approximation (GGA). Using the first-principles calculations, the equilibrium structural parameters of ReC in rocksalt (NaCl), cesium chloride (CsCl), zinc blende (ZB), wurtzite (WZ), nickel arsenide (NiAs) and tungsten carbide (WC) types are successfully obtained, and the results are well consistent with other theoretical data. It is firstly noted that WC-ReC translates into CsCl-ReC at 510.50 GPa by analyzing the enthalpy difference versus pressure. From the calculated elastic constants, the aggregate elastic modulus ( B , G , E ), the Poisson's ratio ( σ ) and the Debye temperature Θ D of WC-type are also derived. It is observed that all the data of WC-ReC obtained increase monotonically with increasing pressure. Meanwhile, the thermodynamic properties of WC-ReC under high temperature and high pressure are investigated applying nonempirical Debye model in the quasi-harmonic approximation.

The temperature dependence of oxygen ion behavior in Zn 2 GeO 4 has been studied from 78 to 873 K. As the temperature increases, the oxygen ions undergo positional disordering along the oxygen vacancies, with the oxygen related modes (ORMs) at 751 cm − 1 and 775 cm − 1 broadening and weakening dramatically. The temperature dependence of the bandwidth of oxygen ion mode is particularly interesting and a model suggested by Andrade and Porto is used to describe the linewidth of a phonon. The activation energy calculated from the ORM is 0.46 eV. Moreover, the motion of oxygen ion in Zn 2 GeO 4 is described in terms of the conventional fast-ion conductor.

A design method was developed to specify the profile of the continuously variable Mach-number nozzle for the supersonic wind tunnel. The controllable contour design technique was applied to obtaining the original nozzle profile, while other Mach-numbers were derived from the transformation of the original profile. A design scheme, covering a Mach-number range of 3.0