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Rett syndrome (RTT), caused by mutations in the X-linked gene encoding methyl-CpG binding protein 2 (MeCP2), severely impairs learning and memory. We previously showed that forniceal deep brain stimulation (DBS) stimulates hippocampal neurogenesis with concomitant improvements in hippocampal-dependent learning and memory in a mouse model of RTT. To determine the duration of DBS benefits; characterize DBS effects on hippocampal neurogenesis; and determine whether DBS influences MECP2 genotype and survival of newborn dentate granular cells (DGCs) in RTT mice. Chronic DBS was delivered through an electrode implanted in the fimbria-fornix. We tested separate cohorts of mice in contextual and cued fear memory at different time points after DBS. We then examined neurogenesis, DGC apoptosis, and the expression of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) after DBS by immunohistochemistry. After two weeks of forniceal DBS, memory improvements lasted between 6 and 9 weeks. Repeating DBS every 6 weeks was sufficient to maintain the improvement. Forniceal DBS stimulated the birth of more MeCP2-positive than MeCP2-negative DGCs and had no effect on DGC survival. It also increased the expression of BDNF but not VEGF in the RTT mouse dentate gyrus. Improvements in learning and memory from forniceal DBS in RTT mice extends well beyond the treatment period and can be maintained by repeated DBS. Stimulation of BDNF expression correlates with improvements in hippocampal neurogenesis and memory benefits. • Memory enhancement persists weeks after forniceal DBS treatment • Repeated DBS treatment maintains memory benefit • DBS skews neurogenesis toward MeCP2-positive cells • DBS stimulates BDNF expression in the hippocampus [ABSTRACT FROM AUTHOR]

• Exposure to new automation technology leads to lower operating performance. • The pattern is driven by financially constrained firms. • Financially unconstrained firms increase investments with new automation exposure. • Financially unconstrained firms have lower costs and higher profits. We find that firms experiencing increases in exposure to new automation technology see deteriorating operating performance in subsequent years. This pattern is driven by financially constrained firms. For firms without financial constraints, increases in automation exposure are associated with increases in profits, increases in fixed assets and employees, decreases in selling, general, and administrative expenses, and increases in profit margin. For firms with financial constraints, increases in automation exposure are positively related to changes in expenses and negatively related to profit margin. It seems firms without financial constraints are in better positions to take advantage of innovations in automation technology. [ABSTRACT FROM AUTHOR]

In this study, steel fiber-reinforced concrete (SFRC) beam structures with regular oriented steel fibers are designed and prepared by using an assembled solenoid device. Fiber orientation is not arranged in a single direction but is similar to the direction of tensile stress of the beam in bending load conditions. With application of inductive test method and image processing technology, fiber orientation coefficient of SFRC was evaluated and increased from 0.5 to 0.7–0.8 after fiber alignment. To describe and analyze the flexural behavior of SFRC beams with regular oriented fibers and glass fiber-reinforced polymer (GFRP) rebars, 14 concrete beams with different parameters were fabricated and subjected to a four-point bending test. Specifically, the parameters included fiber content, fiber orientation, GFRP reinforcement ratio and different layer sections. The results showed that optimizing fiber orientations to the tension zone of the section led to a higher flexural strength and can well restrain the development of crack widths with comparison to randomly distributed fibers. The peak load and energy absorption increased by 7 % and 12.4 % after fiber alignment with a fiber volume fraction of 1.5 %. The combination of randomly and regularly distributed steel fibers in the form of two-layer composite members can be an efficient solution to improve the flexural performance for purpose of the optimum distribution and direction of steel fibers, and reduce the engineering cost. • A magnetic orientation device is designed for SFRC beams with regular oriented fibers. • Fibers had well arrangements with high fiber orientation coefficient. • A flexural test of the ASFRC beams was conducted and investigated. • ASFRC improved the first cracking load and initial stiffness of beams. • The experimental results indicated great flexural performance after aligning fibers to the tension zone. [ABSTRACT FROM AUTHOR]

The stable reliability analysis of dams is a challenging topic in geotechnical engineering safety. Because there are more complex system failure modes and high-dimensional parameters in large solid structures, it is difficult to calculate failure probability efficiently and accurately using general reliability analysis methods. Most methods suffer from complex iterative processes and the curse of dimensionality. In this study, an improved importance sampling method based on multi-objective optimization is proposed and applied to reliability analysis for dam sliding. The optimization function is constructed from the limit state surface and the original probability density. The optimal sampling center is selected from the optimization results by considering the dominant performance function as well as the coefficient of variation of the weight function. Four numerical examples and a case study of the sliding stability of a gravity dam demonstrate the accuracy and efficiency of the proposed method. The results show that the proposed method is not sensitive to the specific multi-objective optimization algorithm used. Simulations using multiple sampling centers perform better overall than simulations using a single sampling center. In particular, the proposed method remains applicable to parallel systems with 20 high-dimensional parameters that are virtually immune to the curse of dimensionality. [ABSTRACT FROM AUTHOR]

The failure mode is a dominant factor of mechanical performance of braided composite tube subjected to axial compression. The failure mode was modified by tailoring stack-up sequence of composite tubes hybridized by bi/tri-axial braided laminate. The thermal photographing and micro-CT scanning methods were employed to monitor the in-situ damage progression and post-mortem specimen, respectively. The results show that the delamination was easy to be induced at the interface nearby tri-axial braided laminate. It attributes to the combination between the crack caused by local buckling of the axial yarns and the crack caused by shear deformation of braiding yarns. By the illumination of this behavior, delamination is controlled to occur at the different position along thickness direction of braided tube by adjusting the stacking sequence of braided laminates. When delamination position transfer from the inner/outer sides to the middle of tube wall, the failure mode transfer from the progressive folding to splaying, which increase the specific energy absorption by 45.77%. [ABSTRACT FROM AUTHOR]

The powder immersion reaction assisted coating (PIRAC) method was used to fabricate a coating on the graphite surface. The graphite was immersed into Cr powder and annealed at 1173–1373 K. The iodine powder was admixed with the Cr powder to investigate the contribution of iodine to the growth and mechanical properties of the coating. After 4 h of PIRAC treatment with or without iodine, Cr7C3- and Cr23C6-based coatings were formed, respectively. The iodinated samples had a higher hardness and thickness, and the friction coefficient was slightly higher than that of the iodine-free sample. The mechanisms for the formation of PIRAC-chromium carbide coatings are explained, and the variations in the produced coatings are discussed. [ABSTRACT FROM AUTHOR]

Objective: CACNA1H is regarded as a gene conferring susceptibility to generalised epilepsy. However, the prognosis of epilepsy patients carrying the CACNA1H missense variants of uncertain significance (VUS) is unknown. A prospective cohort was generated to determine the deleterious effects of these variants and to check whether the presence of these variants affects the prognosis of epilepsy patients.Method: This study was conducted at Xijing Hospital in Xian, China. All patients were followed up for at least 1 year. Previous reports were searched for previously reported variants. Ensembl database was searched for variants in the general population. Combined Annotation Dependent Depletion (CADD) was used to evaluate the deleterious effect of variants. Logistic regression and Cox regression were used for data analysis.Results: The study included 176 epilepsy patients with or without CACNA1H variants. In epilepsy patients with missense variants, we found 35 different variants, including 33 variants with uncertain significance and 2 likely benign variants. No significant difference was observed between the distribution of CADD scores of the variants from this cohort, of the general population, and of those found in previous reports. Among epilepsy patients with missense variants, the number of antiepileptic drugs (AEDs) administered to the patients, a first-degree family history of epilepsy, and possibly the presence of abnormalities in brain radiology findings were correlated with the poorer prognosis. Among the entire cohort, the type of epilepsy, number of AEDs administered, and presence of abnormalities in brain radiology findings were associated with the prognosis of these patients. The deleterious effect of CACNA1H missense variants or their presence was not related to the prognosis of epilepsy patients.Conclusion: The results of our study suggest that CACNA1H variants are related to multiple epilepsy syndromes. However, there is no strong evidence of the correlation between CACNA1H missense variants and a certain type of epilepsy. In our study cohort, both the deleterious effects and the presence of CACNA1H variants were found to be unrelated to the prognosis of patients with epilepsy. These findings suggest that CACNA1H missense variants that are classified as VUS might not influence the outcome of epilepsy. [ABSTRACT FROM AUTHOR]

The endoplasmic reticulum (ER) is the main site for protein synthesis, folding, and secretion, and accumulation of the unfolded/misfolded proteins in the ER may induce ER stress. ER stress is an important participant in various intracellular signaling pathways. Prolonged- or high-intensity ER stress may induce cell apoptosis. Osteoporosis, characterized by imbalanced bone remodeling, is a global disease caused by many factors, such as ER stress. ER stress stimulates osteoblast apoptosis, increases bone loss, and promotes osteoporosis development. Many factors, such as the drug's adverse effects, metabolic disorders, calcium ion imbalance, bad habits, and aging, have been reported to activate ER stress, resulting in the pathological development of osteoporosis. Increasing evidence shows that ER stress regulates osteogenic differentiation, osteoblast activity, and osteoclast formation and function. Various therapeutic agents have been developed to counteract ER stress and thereby suppress osteoporosis development. Thus, inhibition of ER stress has become a potential target for the therapeutic management of osteoporosis. However, the in-depth understanding of ER stress in the pathogenesis of osteoporosis still needs more effort. [Display omitted] • ER stress is implicated in bone remodeling. • ER stress mediates osteogenic differentiation and osteoblast activity. • ER stress regulates osteoclast formation and function. • ER stress has become a target for osteoporosis treatment. [ABSTRACT FROM AUTHOR]

Highlights • A method for simulation of spatial variability of gravity dams was established. • Mean value of the tensile strength has a great influence on the plastic damage. • Research results can be used as a reference for gravity dams with similar profiles. Abstract A method to simulate the random field of the strength parameters of gravity dams considering their spatial variability based on the theory of random fields and the autocorrelation function is proposed. Taking a gravity dam project as an example, the elastic modulus and tensile strength are selected as random variables and the corresponding random fields are generated. Based on the concrete damage plasticity (CDP) model, the effects of the spatial variability of parameters on the dynamic response characteristics of gravity dams are expressed from the standpoints of damage development, residual displacement, and energy dissipation. The impacts of the mean value, coefficients of variation, autocorrelation distance, realizations of the tensile strength random field, and seismic inputs on the structural damage are also investigated. It is found that the spatial variability of parameters, especially the tensile strength, has a great influence on the dynamic damage of gravity dams, and that increasing the mean value of the tensile strength can improve their seismic performance. [ABSTRACT FROM AUTHOR]

An effective way to improve the flight capability and environmental adaptability of aerospace vehicles is to design a morphing aircraft structure, which can actively change their aerodynamic shape. During different physiological activities, the abdomens of bees are regularly deformed to improve the efficiency of movement. This was used as an inspiration for the design of a nose cone for aerospace vehicles. Based on the deformation mechanism of the bee abdomen, a bionic design of a variable configuration morphing nose cone (MNC) mechanism with high sensitivity is proposed, which can realize real-time reverse self-locking of the mechanism via auxiliary branch chains. Theoretical models for the kinematics and dynamics of the MNC mechanism under two configurations are derived, verifying that the proposed mechanism has good kinematic and dynamic characteristics. The theoretical models are validated through simulation studies. In addition, static finite element simulations are performed to verify that the auxiliary locking branch chain can significantly improve the bearing capacity of the proposed mechanism. Moreover, the force and thermal parameters of different configurations of the MNC under corresponding typical working conditions are analyzed, enabling the improvement of the aerospace vehicle aerodynamic characteristics by the morphing of its nose cone. Finally, based on the analytic hierarchy process, different drag and heat flux reduction schemes are comprehensively evaluated. [ABSTRACT FROM AUTHOR]

Most of the plasticizers used during poly (vinyl chloride) processing are typically toxic petroleum-based phthalates. Furthermore, large amount of edible oils become waste all over the world, fortunately, waste cooking oils have the potential to be an economic alternative for synthesizing different biomaterials. This study aimed to synthesis an improved properties and cost competitiveness cleaner bio-plasticizer using waste cooking oil methyl esters as staring raw materials. In this paper, waste cooking oil methyl esters were structurally modified i.e., transesterification and epoxidation reaction, to prepare epoxide waste cooking oil 2-ethylhexyl esters. The in-situ epoxidation was mainly studied by response surface methodology, with optimum conditions: reaction time was 7 h, molar ratio of C C bonds/FA/H 2 O 2 was 1.00/0.35/2.41, and reaction temperature was 65.84 °C with a maximum relative percentage conversion to oxirane of 92%. Also, the plasticizing effectiveness of epoxide waste cooking oil 2-ethylhexyl esters to substitute toxic plasticizer dioctyl phthalate were studied. Results showed that the mechanical and thermal performance of PVC samples was significantly improved with partial substitutions, while the migration resistance was slightly decreased. Comparison with conventional epoxy compound highlighted that epoxide waste cooking oil 2-ethylhexyl esters had superior low temperature property, oxidation stability, and remarkably reduced the glass transition temperature of PVC. In conclusion, the prepared epoxide via structural modification from waste cooking oil methyl esters proved to be an effective alternative to dioctyl phthalate, replacing about 40% of the total plasticizer. This may lead to the eco-development of waste cooking oil materials, and makes the plasticizing process more environmentally friendly. [ABSTRACT FROM AUTHOR]

Banks play an important role in the Japanese economy. This paper addresses some recent changes in Japanese banking industry over the past decade by focusing on the ownership structure of Japanese commercial banks. Ownership type, concentration and shareholder network are investigated to explore the structural changes and further demonstrate their effects on bank performance. [ABSTRACT FROM AUTHOR]

Using a sample of over half a million observations, we explore how investment in employee education affects cost of debt of privately held companies. Findings indicate that, although employee education does help enhance firm performance, it results in a higher cost of debt. However, this negative effect of employee education on cost of debt is weakened by better regional development. [ABSTRACT FROM AUTHOR]

• The usage of correlation between maximum temperature and peak load. • The reconstruction of CT images identifies the debonding distribution and degree. • A novel inspection way of combing infrared imaging and micro CT reconstruction methods. • The role of axial yarns in axial crushing. In this work, the effect of axial yarns on damage behavior of two-dimensional triaxially braided composite(2DTBC) tubes subjected to axial compression was investigated. A novel damage detection method combining infrared thermography and CT scanning was presented. In the area without axial yarns, yarn crossovers were separated from each other due to interlacing patterns. Axial compression caused the braiding yarns to shear deformation like scissors. Inter-yarn de-bonding appeared in crossovers and could not connect. Consequently, it caused a progressively folding failure mode. In contrast, local buckling occurred on axial yarns because of their primary loading behavior. Cracks along the axial yarns formed, which would combine with debonding crossovers caused by the sheared braiding yarn. It resulted in significant inter-layer delamination and consequently splaying failure mode. The energy absorption of composites tube with 18 axial yarns increased by 79.9% at the cost of 27.8% fiber usage more than 3 axial yarns. [ABSTRACT FROM AUTHOR]

It is very important to estimate the mechanical parameters based on monitoring data for investigating the operation behavior of concrete dams. In this paper, an advanced Bayesian parameter estimation method for concrete dams is proposed. The Empirical Mode Decomposition (EMD) is adopted to extract the aging component of the observed deformation sequence, and the hydrostatic component is separated from the remaining periodic term through the statistical regression model (SRM). A hybrid response surface method (HRSM) is proposed as a surrogate model for finite element method (FEM) simulation. The likelihood function, which reflects the error between the observed and simulated deformation, is constructed, then the Bayesian formula for parameter estimation is established. The transitional Markov chain Monte Carlo (TMCMC) algorithm is used to obtain the parameter posterior distribution. The proposed method is applied to estimate the elastic modulus of the GD concrete dam, the parameter posterior distribution is obtained through the fusion of monitoring information and parameter prior information. This method can also avoid the issues of multiple solutions and unreasonable parameter combinations, which may exist in traditional deterministic inversion methods. The case study shows that the proposed method has good applicability in the parameter estimation of concrete dams. [ABSTRACT FROM AUTHOR]

The health monitoring and operation behavior assessment of earth dams are research focuses in geotechnical engineering. Due to the limited monitoring data and the uncertainty of material properties, existing monitoring data-based interpolation methods and mechanism-based finite element method (FEM) can not accurately estimate the dam deformation field. Therefore, studying an accurate estimation method of the deformation field is important to guarantee the serviceability of earth dams. In this paper, a FEM-Bayesian kriging (FBK) method is proposed, in which the FEM is introduced into the Bayesian kriging framework as the source of soft data, taking the FEM results as a trend surface of the deformation field, the spatial distribution of the random residual is determined by the exact monitoring data, thereby the FEM results are corrected. In this method, data-rich but low-precision FEM results and limited but high-precision monitoring data are coupled to approach the real deformation field. A numerical experiment is designed to verify the accuracy of the proposed method, and the estimation error of the FBK is reduced by about 80% compared with traditional methods. The case study of an actual earth dam also shows that the proposed method can effectively characterize the deformation behavior of earth dams. [ABSTRACT FROM AUTHOR]

• Data-based models with EMD are proposed for deformation monitoring of concrete dams. • The proposed models can well simulate the irreversible component of concrete dam deformation and significantly decrease the over-fitting levels. • A new model selection criterion, namely Over-fitting coefficient, is proposed for evaluating and selecting dam health monitoring models. • The Over-fitting coefficient can better reflect over-fitting levels of individual monitoring models compared to traditional model selection criteria. Data-based models are extensively applied in concrete dam health monitoring. In this paper, the Empirical Mode Decomposition (EMD) is adopted to extract and visualize the irreversible component of deformation monitoring sequence. Consequently proper mathematical formulation of the irreversible component of deformation monitoring model for concrete dams can be established, and the problem of improperly assuming the mathematical form of irreversible component when constructing data-based models is well addressed. The periodic component of the deformation time series is modelled by regression and three machine learning algorithms (i.e., Extreme learning machine, Support Vector Machine based on Grid search and Cross-Verification, and Back Propagation Neural Networks optimized by Genetic Algorithm and Simulated Annealing) respectively. The data-based models with the EMD are able to effectively improve the performance of formulating irreversible component of concrete dam deformation and decrease the over-fitting levels. A new model selection criterion, namely Over-fitting coefficient, is proposed for evaluating and selecting the optimum model among candidate monitoring models. The Over-fitting coefficient can better reflect over-fitting levels of individual monitoring models compared to traditional model selection criteria. As a case study, the displacement and strain monitoring data from the YL gravity dam are modeled by data-based models with the EMD and machine learning algorithms. It is shown that data-based models with the EMD are of higher prediction accuracy and lower rate of false alarm in deformation monitoring than traditional models. The Over-fitting coefficient can better reflect over-fitting levels of monitoring models compared to the error measurement criteria and information criteria. The case study highlights the merits of the proposed data-based models and the model selection criterion for health monitoring of concrete dams. [ABSTRACT FROM AUTHOR]

Bearing fault diagnosis suffers from class imbalances and distributional discrepancies of fault data under different working conditions. The class imbalance of the fault class increases the difficulty of learning the classification boundary of the diagnostic model for the minority class. Furthermore, the diversities of feature distributions decrease the diagnostic model's generalizability under various working conditions. Thus, in this paper, a deep adversarial transfer learning model for imbalanced bearing fault diagnosis (deep Imba-DA) is proposed to overcome these problems. In the proposed method, a cost-sensitive deep classifier is used to solve the class imbalance problem, and the domain adversarial subnet with the intraclass maximum mean discrepancy (MMD) is used to minimize the marginal and conditional distributional discrepancy between the source (data under one working condition) and target domain (data under another working condition) simultaneously. The performance of deep Imba-DA is evaluated and analyzed on the Case Western Reserve University (CWRU) and Paderborn datasets. The results show that deep Imba-DA outperforms other baseline methods on bearing diagnostic tasks. • An imbalanced bearing fault diagnostic model under variant conditions is proposed. • A joint transfer network with marginal and conditional distribution is developed. • Pseudo label strategy guarantees a good accuracy and fast convergence. [ABSTRACT FROM AUTHOR]

• Difference of damage modes caused by the boundary conditions of primary load-bearing yarns. • Straightening effect of braided yarns with undulations under low-velocity impact. • Variation of off-axial angles leading to the transition of failure modes. The sensitivity of off-axial angle on impact response was investigated by experimental and numerical methods in this work. Three types of braided laminates with different on/off-axial angles in terms of OA00, OA225 and OA45 were prepared and low-velocity impact tests with various energy levels were performed. Meso-level finite element model (FEM) was also developed to reveal impact damage initiation and development. We discovered that the boundary condition of primary load-bearing yarns depending on the off-axial angles caused the difference of structural deformation and stress distribution of braiding yarns during impact process. Due to the restriction of the pressurized tips, the straightening effect of primary load-bearing yarns with heavy waviness caused its out-of-plane movement and related main cracks in OA00 specimen. In addition, the matrix resin cracks were found at the edge of the specimen because of in-plane shear movement of braiding yarns. As for OA45 specimen, more evident bending deformation was observed, resulting in elevated tensile stress of braiding yarns on non-impact side. The variation of off-axial angle from 0 to 45 degree led to the failure mode transforming from the extensive matrix damage on specimen edge to the severe fiber breakage on non-impact side. As a medium off-axial angle, OA225 specimen exhibited a mixture failure mode to resist impact and achieved excellent performance with respect to higher peak force and delayed load dropping. [Display omitted] [ABSTRACT FROM AUTHOR]

Niobium‑chromium (Nb Cr) carbide coatings were deposited on graphite using the thermo-reactive deposition and diffusion (TRD) technique. The microstructure, hardness, and coefficient of thermal expansion were characterized to search for the optimal treatment parameters for hard and adherent coatings on graphite. The growth rate increased with treatment temperature for fixed treatment duration and remained constant at a constant temperature for about 6 h. The coatings were found to consist of alternating Nb and Cr layers, and this interesting multilayer structure might be explained by the thermodynamics of oxide reduction and carbide formation reactions. Compared to the single-carbides layer, the hardness of the complex coatings increased from about 2500 HV to above 3000 HV, and displayed a smaller gradient of the depth-dependent hardness from the coating to the substrate. The variation of coefficient of thermal expansion of the samples with temperature was similar to that of the graphite substrate at temperatures from 40 to 450 °C. These results showed the effectiveness of the TRD method for synthesizing hard and adherent carbide coatings on graphite, and for other coating/substrate systems with sharply dissimilar mechanical properties. [Display omitted] • Nb Cr complex carbide layers were formed on graphite materials by the TRD technique for the first time. • The maximum coating thicknesses can reach up to 20 μm, positively correlate with the TRD treatment temperature/time. • The elements distributions and unique alternating Nb Cr multilayer structure in the coatings were reported and discussed. • The coatings showed excellent hardness performance (>2500 HV) with good adhesions to the graphite substrates. [ABSTRACT FROM AUTHOR]