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Inflammatory bowel disease (IBD) is a group of chronic intestinal inflammatory diseases with unknown etiology. Gap junctions composed of connexins (Cxs) have been recently validated as an important factor in the development of IBD. Under IBD-induced inflammatory response in the gut, gap junctions connect multiple signaling pathways involved in the interaction between inflammatory cells with other intestinal cells, which altogether mediate the development of IBD. This paper is a narrative review aiming to comprehensively elucidate the biological function of connexins, especially the ubiquitously and predominantly expressed Cx43, in the pathogenesis of IBD. [ABSTRACT FROM AUTHOR]

This paper addresses the fixed‐time adaptive neural distributed control problem of uncertain nonlinear multiagent systems (MASs) with unknown communication link faults. To handle the unknown terms caused by communication link faults and the unknown functions in each agent, a radial basis function neural network (RBF NN) is employed. In contrast to existing methods that focus solely on practical finite‐/ fixed‐time stability of nonlinear systems, the control scheme developed in this paper goes beyond by not only mitigating the effects of unknown communication link faults in nonlinear MASs but also addressing the singularity problem of fixed‐time controllers. These advancements are realized through the design of new power exponent functions and the introduction of new lemmas. This way, the tracking error of MASs converges to a preset range within a fixed time and achieves better control performance. Finally, the feasibility of the proposed scheme is verified through two simulations. [ABSTRACT FROM AUTHOR]

The power system, as a core component of a launch vehicle, has a crucial impact on the reliability and safety of a rocket launch. Due to the limited measurement information inside the engine, it is often challenging to realize fast and accurate anomaly detection. For this reason, this paper introduces the rocket flight state data to expand the information source for anomaly detection. However, engine measurement and rocket flight state information have different data distribution characteristics. To find the optimal data fusion scheme for anomaly detection, a data set information fusion algorithm based on convex optimization is proposed, which solves the optimal fusion parameter using the convex quadratic programming problem and then adopts the adaptive CUSUM algorithm to realize the fast and accurate anomaly detection of engine faults. Numerical simulation tests show that the algorithm proposed in this paper has a higher detection accuracy and lower detection time than the traditional algorithm. [ABSTRACT FROM AUTHOR]

An enhanced finite‐difference time‐domain (FDTD) algorithm is built to solve the transverse electric two‐dimensional Maxwell's equations with inhomogeneous dielectric media where the electric fields are discontinuous across the dielectric interface. The new algorithm is derived based upon the integral version of the Maxwell's equations as well as the relationship between the electric fields across the interface. To resolve the instability issue of Yee's scheme (staircasing) caused by discontinuous permittivity across the interface, our algorithm revises the permittivities and makes some corrections to the scheme for the cells around the interface. It is also an improvement over the contour‐path effective permittivity algorithm by including some extra terms in the formulas. The scheme is validated in solving the scattering of a dielectric cylinder with exact solution from Mie theory and is then compared with the above contour‐path method, the usual staircasing and the volume‐average method. The numerical results demonstrate that the new algorithm has achieved significant improvement in accuracy over other methods. Furthermore, the algorithm has a simple structure and can be merged into current FDTD software packages easily. The C++ source code for this paper is provided as supporting information for public access. [ABSTRACT FROM AUTHOR]

The aims of the present study were to investigate the role of sphingosine kinase 2 (Sphk2) in hypertrophic scar (HS) formation and its underlying mechanisms. The expression levels of Sphk2 and Smad7 in HS tissues and healthy skin tissues of patients undergoing plastic surgery were determined using immunohistochemical staining. Subsequently, the expression levels of Sphk2 and collagen I in human embryonic skin fibroblasts (control) and human HS fibroblasts (HSF) were detected using western blot analysis and immunofluorescence assay, respectively. Following Sphk2 silencing, Smad7 overexpression or both Sphk2 and Smad7 silencing, HSF proliferative ability was assessed using Cell Counting Kit-8 assay and proliferation-associated proteins were evaluated using western blot analysis. In addition, the level of apoptosis in HSF was assessed using flow cytometry and expression levels of apoptotic-associated proteins were determined using western blotting. Furthermore, the expression levels of collagen I and proteins in the TGF-β1/Smad signaling pathway were detected using western blot analysis. The results indicated that the expression of Sphk2 was significantly increased, while Smad7 expression was decreased in HS tissue. Moreover, the upregulation of Sphk2 and collagen I expression levels was identified in HSF. The present results also indicated that Sphk2 silencing or Smad7 overexpression inhibited proliferation, but promoted apoptosis of HSF, coupled with changes in the expression levels of proliferation-associated proteins, with an increase in p21 and a decrease in cyclin D1 expression levels, and apoptosis-associated proteins, with an increase in Bax and cleaved caspase-3, and a decrease in Bcl-2, which were reversed following transfection with both Sphk2 and Smad7 using small interfering RNA in HSF. In addition, the expression levels of transforming growth factor-β1, phosphorylated (p)-Smad2, p-Smad3 and collagen I were reduced following Sphk2 silencing or Smad7 overexpression, which were abolished by silencing both Sphk2 and Smad7. Collectively, the present results indicated that inhibition of Sphk2 attenuated HS formation via upregulation of Smad7 expression, thus Sphk2 may serve as a potential therapeutic target for the treatment of HS. [ABSTRACT FROM AUTHOR]

This paper investigates the attitude and position tracking control problem of the Lead–Wing close formation system with unknown multiplicative actuator faults. In close formation flight, the movement of the Wing unmanned aerial vehicle (UAV) is influenced by the vortex effects of the neighboring Lead UAV. This situation requires a modeling of the aerodynamic coupling vortex effects and linearization on the basis of optimal close formation geometry. Adaptive actuator fault parameters are identified by merging the improved unknown input observers, and adaptive laws with projection functions are presented for actuator fault tracking. The sufficient condition corresponding to the existence of unknown input observers is given. Then, an adaptive fault-tolerant H-infinity output feedback control scheme is developed to guarantee the asymptotic stability, H-infinity closed-loop system performance, and attitude and position tracking properties while the Lead UAV is being maneuvered. Simulation results of the Lead–Wing close formation flight validate the efficiency of the proposed fault-tolerant control algorithm. [ABSTRACT FROM AUTHOR]

Summary: This study investigates the consensus problem of multiple 3‐DOF laboratory helicopters modeled with system nonlinearity, uncertainty, and actuator faults. The simultaneous additives and partial loss of effectiveness actuator faults are considered. The fault detection hierarchy, the healthy control hierarchy, and the fault‐tolerant control hierarchy constitute the hierarchical structure of multihelicopter systems. The fault‐tolerant consensus protocol is switched from the healthy control hierarchy once the actuator fault is detected in the fault detection hierarchy. An adaptive fault‐tolerant consensus control scheme is developed on the basis of the instantaneous and integral estimations to compensate simultaneously for system nonlinearity, uncertainty, and actuator faults and to guarantee the mean‐square consensus in a completely distributed form. Simulation results are presented to validate the effectiveness of the proposed adaptive fault‐tolerant consensus control algorithm. [ABSTRACT FROM AUTHOR]

Dynamic milling force under milling vibration is an important indicator for evaluating the milling stability of a milling cutter. The existing modeling methods for milling force ignore the milling vibration for the instantaneous milling behavior of a milling cutter and its teeth, the instantaneous cutter-workpiece engagement, and the milling force. The dynamic characteristics of the milling force need to be revealed. According to the influence characteristics of milling vibration on instantaneous cutter-workpiece engagement, a method for calculating the instantaneous milling attitude angle and the milling motion trajectory of a milling cutter and its cutter teeth was proposed that revealed the changing characteristics of the instantaneous milling behavior of the cutter teeth. The differential element method was used to characterize the distribution state of the milling force of a cutter tooth. The method for calculating the cutting layer thickness of the milling differential element and the instantaneous cutting boundary of the milling edge was put forward, and the instantaneous milling force model of the milling edge was established. By constructing an instantaneous milling force system for multi-tooth milling, a method for calculating the position vector relation variable and the force vector relation variable of the instantaneous milling force of adjacent cutter teeth was proposed, thus revealing the dynamic characteristics of the instantaneous milling force relationship of the adjacent cutter teeth. The dynamic characteristics and the response characteristics of the milling force were tested. The results showed that the calculated results of the dynamic milling force change characteristics of the milling cutter were quite similar to the experimental results. The influence mechanisms of milling vibration, cutter structure parameters, and milling parameters on the dynamic milling force of a milling cutter can be identified with the use of the above models and methods. [ABSTRACT FROM AUTHOR]

Incipient faults in electrical drive systems will evolve into faults or failures as time goes on. Successful detection and diagnosis of incipient faults can not only improve the safety and reliability but also provide optimal maintenance instructions for electrical drive systems. In this paper, an integration strategy of data-driven and deep learning-based method is proposed to deal with incipient faults. The salient advantages of the proposed method can be summarized as: (1) The moving average technique is firstly introduced into the canonical correlation analysis (CCA) framework, which makes the new residual signals more sensitive to incipient faults than the traditional CCA-based method; (2) Based on the defined residual signals, the new test statistics cooperating closely with Kullback–Leibler divergence (KLD) are proposed from the probability viewpoint, which can greatly improve the fault detectability; (3) It is of high computational efficiency because the estimation of probability density functions of residual signals is skilly avoided; (4) Based on the new developed test statistics, the fault matrices are defined and regarded as the input of convolutional neural network (CNN) whose feature extraction ability is highly improved compared with the traditional method, which helps to accurately diagnose of incipient faults; (5) The proposed method can be implemented without any priori knowledge on system information. Theoretical analysis and three sets of experiments on a practical electrical drive system demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Background: DnaJ/Hsp40 homolog, subfamily B, member 6 (DNAJB6) is significantly down-regulated in esophageal squamous cell carcinoma (ESCC), while its complicated molecular mechanisms are still unknown.Aims: To investigate the relationship between DNAJB6 and ESCC.Methods: The expression of DNAJB6 was detected in ESCC patient by Western blot and immunohistochemistry. To overexpress DNAJB6a by lentivirus infection, colony-forming, CCK-8, transwell, mouse xenograft assays were utilized to verify the proliferous, invasive, and migratory role of DNAJB6a in ESCC cells. The MDA and GSH assays determine whether DNAJB6a participates in cell redox reaction. The variation of AKT and GPX4 was detected by Western blot.Results: The correlation between DNAJB6 level and lymph node metastasis in ESCC patient was negative. Overexpressing DNAJB6a shows tumor-suppressive effects in vitro and in vivo. In addition, DNAJB6a overexpression was accompanied together with a remarkable reduction in the protein levels of GPX4 and phosphorylated AKT (p-AKT).Conclusion: DNAJB6 plays an important anti-oncogenic role in ESCC evolvement via ferroptosis. [ABSTRACT FROM AUTHOR]

Semantic segmentation for lightweight object parsing is a very challenging task, because both accuracy and efficiency (e.g., execution speed, memory footprint or computational complexity) should all be taken into account. However, most previous works pay too much attention to one-sided perspective, either accuracy or speed, and ignore others, which poses a great limitation to actual demands of intelligent devices. To tackle this dilemma, we propose a novel lightweight architecture named Context-Integrated and Feature-Refined Network (CIFReNet). The core components of CIFReNet are the Long-skip Refinement Module (LRM) and the Multi-scale Context Integration Module (MCIM). The LRM is designed to ease the propagation of spatial information between low-level and high-level stages. Furthermore, channel attention mechanism is introduced into the process of long-skip learning to boost the quality of low-level feature refinement. Meanwhile, the MCIM consists of three cascaded Dense Semantic Pyramid (DSP) blocks with image-level features, which is presented to encode multiple context information and enlarge the field of view. Specifically, the proposed DSP block exploits a dense feature sampling strategy to enhance the information representations without significantly increasing the computation cost. Comprehensive experiments are conducted on three benchmark datasets for object parsing including Cityscapes, CamVid, and Helen. As indicated, the proposed method reaches a better trade-off between accuracy and efficiency compared with the other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

To provide a systematic and rigorous re-examination of the well-known Polanyi's rules, excitation functions of several A + BC(v = 0, 1) reactions are determined using the Chebyshev real wave packet method on accurate potential energy surfaces. Reactions with early (F + H2 and F + HCl), late (Cl + H2), and central (H/D/Mu + H2, where Mu is a short-lived light isotope of H) barriers are represented. Although Polanyi's rules are in general consistent with the quantum dynamical results, their predictions are strictly valid only in certain energy ranges divided by a cross-over point. In particular, vibrational excitation of the diatomic reactant typically enhances reactivity more effectively than translational excitation at high energies, while reverse is true at low energies. This feature persists irrespective of the barrier location. A sudden vector projection model is proposed as an alternative to Polanyi's rules. It is found to give similar, but more quantitative, predictions about mode selectivity in these reactions, and has the advantage to be extendible to reactions involving polyatomic molecules. [ABSTRACT FROM AUTHOR]

Eu3+ and Er3+ co-doped YNbO4 powder phosphors were synthesized by a traditional high-temperature solid-state reaction method. A laser of 487.6 nm wavelength was selected to be the excitation source which can pump Eu3+ ions from its thermally populated low-lying 7F2 ground state to the excited state 5D2 and lift the Er3+ ions from their 4I15/2 to 4F7/2 states. Fluorescence intensity ratio (FIR) between the 5D0 → 7FJ emissions of Eu3+ and 4S3/2 → 4I15/2 emissions of Er3+ ions is remarkably dependent on temperature because of the dramatic increase of Eu3+ luminescence against a slight quenching of Er3+ luminescence with the rise of temperature. This temperature sensitive FIR can be favorably employed for temperature sensing, owing to this novel scheme of 5D2 excitation, instead of 5D0, from 7F2 and utilizing Er3+ luminescence as a reference for FIR measurements. This sample is also prominent for its excellent signal-to-noise ratio and is a promising candidate for an optical temperature sensor. [ABSTRACT FROM AUTHOR]

This paper studies the distributed adaptive output-feedback fault tolerant control problem for leader-following multiagent systems with sensor faults. By using the approximation theory of neural networks, an unknown continuous function is approximated, and the problem that the neural network output deviates from the true approximation of the unknown function due to the faults of neural network input is solved. A filter observer is adopted to estimate the unmeasurable states. Based on the adaptive backstepping technique and fault tolerant control technique, a distributed adaptive neural output-feedback control scheme is proposed to guarantee the output consensus of all nodes under directed communication graphs. Based on graph theory and Lyapunov stability theory, it is proved that the proposed adaptive neural control scheme guarantees the uniformly ultimate boundness of the closed-loop systems, and the tracking errors converge to a small adjustable neighborhood of the origin. The simulation results demonstrate the effectiveness of the control approach in this paper. [ABSTRACT FROM AUTHOR]

AZ31 magnesium alloy sheets were prepared by a conventional extrusion (CE) and a novel integrated extrusion with side direction strain (SE). The microstructure characterizations, crystallographic texture and mechanical property tests were carried out and compared between the extruded Mg alloy sheets processed by CE and SE. The results indicated that the SE sheets exhibited an excellent combination of strength and ductility. To reveal the side strain effect, the finite element model was employed to investigate the effective stress and strain behavior of the AZ31 magnesium alloy sheets during CE and SE processes. It was found that the SE process was effective in weakening the stress and strain concentration. This implied that it developed an additional side direction strain through the sheet thickness during the hot extrusion. Meanwhile, the side strain shear paths could promote the local accumulation of dynamically recrystallized grains and increase the random high-angle boundaries to achieve weak (0002) basal texture. Important factors including the side strain path and extrusion parameters need to be taken into account to understand the deformation mechanism and microstructure evolution. Image 1 • A novel extrusion path can introduce a weak texture for Mg alloy sheets. • An additional side direction strain along TD is developed. • The room temperature ductility and formability are remarkably enhanced. [ABSTRACT FROM AUTHOR]

This paper addresses the fault-tolerant control issue for a class of flexible air-breathing hypersonic vehicles. Firstly, a longitudinal dynamic model with process faults is established, which contains an ordinary differential equation (ODE) for rigid body, an Euler–Bernoulli beam equation for flexible modes, and a new boundary connection between them; Secondly, a novel fault-tolerant control scheme is proposed to accommodate process faults and suppress vibrations, which relies on the direct Lyapunov method and the bilinear matrix inequalities (BMIs) technique; Thirdly, in order to compute the gain matrices of the fault-tolerant control law, a two-step algorithm is provided to solve the BMI feasibility problem in terms of linear matrix inequality optimisation technique. Finally, the simulation results are provided to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper investigates the position-tracking and attitude-tracking control problem of close formation flight with vortex effects under simultaneous actuator and sensor faults. On the basis of the estimated state and fault information from unknown input observers and relative output information from neighbors, an integration of decentralized fault estimation and distributed fault-tolerant control is developed to deal with bidirectional interactions and to guarantee the asymptotic stability and $H_\infty$ performance of close formations. [ABSTRACT FROM AUTHOR]

Under the influence of a high-speed, interrupted-cutting impact load, the damage degree quickly increases following any structural damage in a milling cutter. The presence of structural damage must be explored given the fact that these conditions may result in irreparable and serious accidents if not immediately detected. Milling cutter damage has multi-scale characteristics. Therefore, the single-scale damage research method cannot reveal the formation and evolution of the multi-scale damage of a milling cutter, which makes it difficult to identify and control the damage of a milling cutter. The damage scales of a milling cutter are divided according to the multi-scale characteristics of milling cutter damage. Based on continuum mechanics, the dislocation theory, and molecular dynamics, the damage characterization method of the macrostructure, lattice structure, and mesoscopic structure of a milling cutter were proposed in this study. Utilizing the multi-scale finite element method and the force connection method, the loading boundary conditions of the multi-scale damage of a milling cutter were established in order to achieve a trans-scale load transfer. The damage characteristics of the macrostructure, lattice structure, and mesoscopic structure of the milling cutter were studied, and the critical value of the multi-scale damage characteristic variable of the milling cutter was obtained. Thereby, the damage position, types, and size and damage occurrence sequences of the milling cutter were revealed, and the damage formation process and the characteristics of the milling cutter were clarified. Based on this, a method for recognizing the multi-scale damage in a milling cutter was proposed and verified by experiments. The results showed that the above method could effectively identify multi-scale damage characteristics and reveal the formation and evolution process of the damage of a high-efficiency milling cutter. [ABSTRACT FROM AUTHOR]

In this paper, the problem of global state-feedback control is investigated for a class of switched nonlinear time-delay systems. In order to obtain a less-conservative common dynamic gain update law across subsystems, we construct different dynamic gain update laws for individual subsystems. Based on multiple Lyapunov function approach and adding one power integrator technique, the delay-independent controllers for all subsystems and a proper switching law are designed to guarantee that the states of the switched nonlinear time-delay systems can be globally asymptotically to the origin; meanwhile, all the signals of the closed-loop system are bounded. Finally, an example is provided to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Long-time operation of traction systems under severe working environment easily induces various faults in high-speed trains, and thereby puts passengers in an unsafe position. Thanks to widely equipped sensors in high-speed trains and the technical development of advanced data analysis techniques, real-time fault detection (FD) using only online data is an inevitable trend to improve safety and reliability of high-speed trains. In this paper, an edge computing-aided FD framework for traction systems in high-speed trains is proposed; the superior advantages include: 1) its implementation can be easily carried out without system information such as accurate mathematical models of traction systems; 2) it has the well-deserved expansibility without being redesigned for the control structure of traction systems; 3) it nearly does not occupy resource of traction control units, and it does not overburden the information transmission systems. This highly intelligent FD framework using edge computing is firstly speculated in details, and its core theory is then applied to a dSPACE platform of high-speed trains for verification. [ABSTRACT FROM AUTHOR]

Schisandra chinensis lignans are the main active components of the traditional Chinese medicine Schisandra chinensis in East Asia. At present, there are more and more medicines and health foods in which the total S. chinensis lignans extracts are considered as the main active components, but little research has been done on the active components of S. chinensis lignans in the blood and main target organs. In this study, the components of S. chinensis lignans in the blood, liver and brain tissues of rats at different time points after the intragastrical administration of S. chinensis lignans were determined by a metabolomic method based on high‐performance liquid chromatography with quadrupole time‐of‐flight tandem mass spectrometry spectrometry. Twelve Schisandra chinensis lignans and 15 metabolites in the blood, liver, and brain of rats were identified. The results showed that the main metabolic ways of S. chinensis lignans in rats were hydroxylation, demethylation, and demethylation‐hydroxylation, and some of them might undergo demethylation, dehydrogenation, epoxidation, and elimination reaction. The time‐dose characteristics of S. chinensis lignans and their metabolites in the blood and target organs were analyzed, which may be helpful to elucidate the active substances that really exert the pharmacodynamic effects of S. chinensis lignans in organisms. [ABSTRACT FROM AUTHOR]

Summary: Free fatty acids (FFAs) and triacylglycerols (TAGs) are the main components of edible vegetable oils. In this work, electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) was employed to characterise the molecular composition of FFAs and TAGs in various vegetable oils, including soybean, rapeseed, corn, sunflower, peanut, linseed and olive oils. Semiquantitative analysis of FFAs and structural analysis of TAGs by MS/MS were further conducted to reveal the differences in the molecular compositions of the various vegetable oils. It was found that each vegetable oil has characteristic fingerprints of FFAs and TAGs. MS/MS measurements showed that the high‐abundance TAGs in each vegetable oil were mainly composed of their abundant FFAs and glycerol. FFA and TAG fingerprints of genetically modified (GM) and nongenetically modified (non‐GM) vegetable oils were similar, exhibiting only subtle differences, as confirmed by principal component analysis (PCA). [ABSTRACT FROM AUTHOR]

An effective strategy for analyzing and diagnosing multiple faults is developed, based on the concise causality structure obtained by multisignal modeling and the fault source signals extracted by blind source separation (BSS). The key idea is enlightened by the need to handle the redundant test signals and the multiple fault ambiguity groups when applying multisignal modeling for multiple fault diagnosis. Considering that BSS is inherently suitable to extract the independent source information, it is integrated into the multisignal model to reconstruct the causality structure that will have superior diagnosticability. Preliminary study on test point design is also presented in the proposed strategy. The proposed multiple fault diagnosis strategy has been verified on a hydraulic automatic gauge control simulation system in a cold rolling mill. Results show that it can use less test information to effectively diagnose all simulated single and multiple faults. [ABSTRACT FROM AUTHOR]

The paper proposes new instrumental variables estimators for the slope parameters of a panel data model with classical endogeneity in which all the observables – including the instruments – may have a common factors structure. These estimators are shown to be consistent and asymptotically normal under weak regularity conditions. A small Monte Carlo simulation shows that these estimators compare favourably to existing estimators. [ABSTRACT FROM AUTHOR]

A single pixel in time of flight cameras receives multiple reflected light from different scene points, resulting in erroneous depth information. In this paper, based on the proposed sparse decomposition, a coarse and fine sparse decomposition based on compressed sensing is applied to multipath separation. The applied method uses a linear combination of multiple frequency signals to modulate the source. The measured vector obtained through finite random measurements is subjected to two sparse decompositions – rough separation and detailed positioning, and finally the minimum direct path depth is accurately recovered. Under the premise of the same number of measurements, calculation amount, and storage space, the accuracy of the coarse and fine sparse decomposition based on compressed sensing is improved by nearly an order of magnitude compared to the sparse decomposition without compressed sensing. Moreover, our method can basically achieve multi-path separation accuracy to the sub-millimeter level. [ABSTRACT FROM AUTHOR]

This paper studies a fault-tolerant control problem of singularly perturbed systems with faults and disturbances. The original faulty system is decomposed into a reduced subsystem and a boundary-layer subsystem. Then, a composite fault-tolerant controller is designed with one part dealing with the reduced subsystem and the other dealing with the boundary-layer subsystem. Through regulating the two parts of the controller, the original faulty system is input-to-state stable with respect to disturbances when the perturbation parameter is small enough. An application to the longitudinal control system of a hypersonic vehicle is given at last. Its singularly perturbed model is derived and a composite fault-tolerant controller is designed to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Diketopyrrolopyrrole (DPP) derivatives have been widely used as the electron-withdrawing unit to construct donor–acceptor (D–A) conjugated systems in organic electronics. The 3,6-position flanking aromatic rings of DPP could strongly influence the optoelectronic properties of DPP-based materials. In this study, a stepwise synthesis strategy was used to prepare monofluorinated and difluorinated dithienyl-DPP. The single crystal of the difluorinated model compound was also obtained. Three polymers based on bithiophene donor and dithienyl-DPP acceptor with different fluorinated positions were synthesized. And preliminary investigations of the influence of fluorination on the optoelectronic properties were performed. [ABSTRACT FROM AUTHOR]

Overuse of portable electronic devices depletes one's attention capacity, a critical cognitive resource. Although contact with nature promotes attentional functioning, we do not know the extent to which exposure to nature and the use of electronic devices interact to promote or inhibit attentional functioning. In this study, 81 participants performed cognitive tasks and then were randomly assigned to one of four rest treatments: green settings with or without a laptop computer and barren settings with or without a laptop computer. Attention was measured three times. Analysis showed a significant effect for both setting and use of a laptop as well as a significant interaction between setting and laptop use. A further analysis controlling for time spent focused on the laptop screen produced similar results. The findings show that using an electronic device in green settings substantially counteracts the attention enhancement benefits of green spaces. [ABSTRACT FROM AUTHOR]

In this paper, a novel descriptor estimator-based incipient fault estimation scheme is designed for Lipschitz nonlinear descriptor systems with process disturbances and measurement output noises. By using the proposed estimator, incipient sensor faults, abrupt actuator faults, and measurement noises can be estimated asymptotically. Application results conducted on a three-phase inverter system of China railway high-speed trains are given to illustrate the effectiveness of the developed approach. The main contributions are summarized in two aspects: 1) the unified framework designed for actuator and sensor fault reconstruction/estimation problem is capable of dealing with actuator and sensor faults at the same time and 2) a linear matrix inequality optimization method is formulated to achieve optimal performance of signal estimation. [ABSTRACT FROM AUTHOR]

Ovarian cancer is one of the most deadly cancers with rapid proliferation and poor prognosis among patients. Therapies focusing on regulation of tumor immunity and microenvironments are developing. MiR-217 was dysregulated in cancer progress and plays important roles in tumorigenesis and metastasis. However, the role of miR-217 in regulation of macrophage polarization and its underlying molecular mechanism remain unclear. The expression of miR-217 in ovarian cancerous tissues and cell lines were assessed by qRT-PCR. And we detected the staining of CD86 and CD206 via flow-cytometry and the levels of Arg-1 and CCR2 by western-blot in order to evaluate M2 macrophage polarization. The targeting regulation of miR-217 on pro-inflammatory factor IL-6 was assessed by dual-luciferase reporter assay and western-blot. ELISA assay was used to evaluate the secretion of IL-6 and IL-10 of cells. MiR-217 was found to be downregulated in ovarian cancerous tissues and cell lines. This downregulation correlated with an increased expression of the IL-6, Arg-1, CCR2, and CD206 gene. The overexpression of miR-217 in SKOV3 cells can inhibit the polarization of macrophages towards an M2-like phenotype. We also found that IL-6 was validated to induce M2 macrophage polarization and its secretion in SKOV-3 cells was inhibited by miR-217 directly. Moreover, we revealed that miR-217 suppressed M2 macrophage polarization partly thought JAK/STAT3 signal pathway. Taken together, these findings indicate that miR-217 inhibits tumor-induced M2 macrophage polarization through targeting of IL-6 and regulation JAK3/STAT3 signaling pathway, which may provide a potential therapeutic target for treating ovarian cancer. [ABSTRACT FROM AUTHOR]

A BN membrane with a distinct nanoconfinement effect toward efficient ethylene/ethane separation is presented. The horizontal and inclined self‐assembly of 2D BN nanosheets endow the BN membrane with abundant percolating nanochannels, and these nanochannels are further decorated by reactive ionic liquids (RILs) to tailor their sizes as well as to achieve nanoconfinement effect. The noncovalent interactions between RIL and BN nanosheets favor the ordered alignment of the cations and anions of RIL within BN nanochannels, which contributes to a fast and selective ethylene transport. The resultant membranes exhibit an unprecedented separation performance with superhigh C2H4 permeance of 138 GPU and C2H4/C2H6 selectivity of 128 as well as remarkably improved long‐term stability for 180 h, outperforming reported state‐of‐the‐art membranes. [ABSTRACT FROM AUTHOR]

A BN membrane with a distinct nanoconfinement effect toward efficient ethylene/ethane separation is presented. The horizontal and inclined self‐assembly of 2D BN nanosheets endow the BN membrane with abundant percolating nanochannels, and these nanochannels are further decorated by reactive ionic liquids (RILs) to tailor their sizes as well as to achieve nanoconfinement effect. The noncovalent interactions between RIL and BN nanosheets favor the ordered alignment of the cations and anions of RIL within BN nanochannels, which contributes to a fast and selective ethylene transport. The resultant membranes exhibit an unprecedented separation performance with superhigh C2H4 permeance of 138 GPU and C2H4/C2H6 selectivity of 128 as well as remarkably improved long‐term stability for 180 h, outperforming reported state‐of‐the‐art membranes. [ABSTRACT FROM AUTHOR]

As noted in the epigraph, a map was long ago seen as the map of the map, the map of the map, of the map, and so on endlessly. This recursive perspective on maps, however, has received little attention in cartography. Cartography, as a scientific discipline, is essentially founded on Euclidean geometry and Gaussian statistics, which deal respectively with regular shapes and more or less similar things. It is commonly accepted that geographic features are not regular and that the Earth's surface is full of fractal or scaling or living phenomena: far more small things than large ones are found at different scales. This article argues for a new paradigm in mapping, based on fractal or living geometry and Paretian statistics, and – more critically – on the new conception of space, conceived and developed by Christopher Alexander, as neither lifeless nor neutral, but a living structure capable of being more living or less living. The fractal geometry is not limited to Benoit Mandelbrot's framework, but tends towards Christopher Alexander's living geometry and is based upon the third definition of fractal: A set or pattern is fractal if the scaling of far more small things than large ones recurs multiple times. Paretian statistics deals with far more small things than large ones, so it differs fundamentally from Gaussian statistics, which deals with more or less similar things. Under the new paradigm, I make several claims about maps and mapping: (1) the topology of geometrically coherent things – in addition to that of geometric primitives – enables us to see a scaling or fractal or living structure; (2) under the third definition, all geographic features are fractal or living, given the right perspective and scope; (3) exactitude is not truth – to paraphrase Henri Matisse – but the living structure is; and (4) Töpfer's law is not universal, but the scaling law is. All these assertions are supported by evidence, drawn from a series of previous studies. This article demands a monumental shift in perspective and thinking from what we are used to in the legacy of cartography and GIS. [ABSTRACT FROM AUTHOR]

We have previously demonstrated the hepatoprotective effect of Schisandra chinensis polysaccharides (SCP) against the liver injury induced by alcohol, high-fat diet, and carbon tetrachloride in mice. In this study, we investigated the effect of SCP against the immunological liver injury induced by concanavalin A (Con A) in mice. The results showed that SCP could significantly reduce the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in the serum of mice with immunological liver injury. SCP could significantly decrease the content of malondialdehyde (MDA) and nitric oxide (NO) and increase the activity of superoxide dismutase (SOD) and glutathione (GSH) in the liver tissue. SCP could significantly increase the number of CD4+ and decrease the number of CD8+ in the peripheral blood, and elevate the ratio of CD4+/CD8+. SCP could significantly downregulate the expression of Kelch-like ECH-associated protein 1 (Keap1) and upregulate the expression of nuclear factor-erythroid 2-related factor2 (Nrf2) and downstream gene heme oxygenase-1 (HO-1), and downregulate the expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (MyD88), and nuclear factor-kappa B (NF-κB) proteins. This study indicates that SCP can reduce the release of a large number of inflammatory factors to inhibit the oxidative stress in mice with the immunological liver injury induced by Con A, and its mechanism is closely related to the regulation of Nrf2/antioxidant response element and TLR4/NF-κB signaling pathways. [ABSTRACT FROM AUTHOR]

• The application background of helium compressor is introduced. • The theoretical research of helium compressor is reviewed. • The challenges and potential breakthroughs were highlighted. The power conversion unit of a high-temperature gas-cooled reactor (HTGR) could be a closed Brayton cycle power plant with helium as the working fluid. The helium compressor is the main component of such a power conversion unit, and its performance has significant effects on the power output and cycle efficiency. However, helium is difficult to compress owing to its thermo-physical properties, making the helium compressor design challenging. This paper provides a review of the studies and applications of helium compressors. The background of the helium compressor is introduced, the theoretical studies on helium compressors are reviewed and the development of the helium compressor is discussed. Based on the review, the helium compressor future challenges and potential breakthroughs in different aspects are highlighted. The results show that helium compressor development requires a special design technique which takes the thermo-physical properties of helium into consideration and advanced technologies suitable for helium compressor should focus on development. [ABSTRACT FROM AUTHOR]

In major ischemic stroke caused by a large artery occlusion, neuronal loss varies considerably across individuals without revascularization. This study aims to identify which patient characteristics are most highly associated with this variability. Demographic and clinical information were retrospectively collected on a registry of 878 patients. Imaging biomarkers including Alberta Stroke Program Early CT score, noncontrast head computed tomography infarct volume, perfusion computed tomography infarct core and penumbra, occlusion site, collateral score, and recanalization status were evaluated on the baseline and early follow-up computed tomography images. Infarct growth rates were calculated by dividing infarct volumes by the time elapsed between the computed tomography scan and the symptom onset. Collateral score was graded into four levels (0, 1, 2, and 3) in comparison with the normal side. Correlation of perfusion computed tomography and noncontrast head computed tomography infarct volumes and infarct growth rates were estimated with the nonparametric Spearman's rank correlation. Conditional inference trees were used to identify the clinical and imaging biomarkers that were most highly associated with the infarct growth rate and modified Rankin Scale at 90 days. Two hundred and thirty-two patients met the inclusion criteria for this study. The median infarct growth rates for perfusion computed tomography and noncontrast head computed tomography were 11.2 and 6.2 ml/log(min) in logarithmic model, and 18.9 and 10.4 ml/h in linear model, respectively. Noncontrast head computed tomography and perfusion computed tomography infarct volumes and infarct growth rates were significantly correlated (rho=0.53; P < 0.001). Collateral status was the strongest predictor for infarct growth rates. For collateral=0, the perfusion computed tomography and noncontrast head computed tomography infarct growth rate were 31.56 and 16.86 ml/log(min), respectively. Patients who had collateral >0 and penumbra volumes>92 ml had the lowest predicted perfusion computed tomography infarct growth rates (6.61 ml/log(min)). Collateral status was closely related to the diversity of infarct growth rates, poor collaterals were associated with a faster infarct growth rates and vice versa. [ABSTRACT FROM AUTHOR]

A small amount of cerium (below 1.0 wt%) addition to AZ91 alloy have been investigated on the hot tearing susceptibility (HTS) at a cooling rate of 1.5Ks−1. The HTS increased to a maximum value with a cerium addition of 0.6 wt% and then decreased to a stable status as cerium was gradually added. Due to high chemical activity, cerium into the melts can react with aluminum to form an Al 11 Ce 3 intermetallic compound. X–ray diffraction results also confirmed the existence of Al 11 Ce 3. The Al 11 Ce 3 increased with the presence of the needle-like and block morphology. As cerium levels increased, the amount of Mg 17 Al 12 decreased. The variations between Mg 17 Al 12 and Al 11 Ce 3 resulted in a similar normal distribution of the HTS in AZ91 alloy. The findings were further verified through the microstructure evolution and the surface morphology of fracture. Image 1 • A normal–like distribution of HTS presented with cerium content increased. • The coarsest dendrites were observed in the AZ91–0.4Ce alloy and not in the AZ91–0.6Ce alloy with the highest HTS. • The morphology of Al 11 Ce 3 evolved from needle–like to short rod–like with cerium increase, and finally to block. [ABSTRACT FROM AUTHOR]

A study on hypersonic vehicle (HSV) with centroid shift and actuator fault is made to investigate the adaptive fault‐tolerant control for stability recovery of HSV operating in off‐nominal conditions. Based on the modelling and analyzing the influence of centroid shift and actuator fault on HSV, the centroid shift can cause system uncertainty, variation of inertial matrix, eccentric moment and strong coupling between the longitudinal and lateral motions, resulting in the high demand for controller. According to the difference of response time, the attitude system of HSV is divided into slow and fast loop. For handling the effect of centroid shift, actuator fault and external disturbance, an improved sliding mode controller combined with adaptive estimator is designed for the slow‐loop. Nonlinear general predictive controller (NGPC) assisted by adaptive radial basis function neural network (RBFNN) is developed for fast‐loop. In addition, the nonsingular improvements to fast‐loop controller are also made to cope with such the problem caused by the estimation of inertial matrix. The stability and tracking ability of the system are analyzed by the Lyapunov theorem of stability. At last, the simulation results show that the fault‐tolerant control algorithm provided in this paper is very effective. [ABSTRACT FROM AUTHOR]

Quantum state-to-state dynamics for the quenching process Br(2P1/2) + H2(vi = 0, 1, ji = 0) → Br(2P3/2) + H2(vf, jf) has been studied based on two-state model on the recent coupled potential energy surfaces. It was found that the quenching probabilities have some oscillatory structures due to the interference of reflected flux in the Br(2P1/2) + H2 and Br(2P3/2) + H2 channels by repulsive potential in the near-resonant electronic-to-vibrational energy transfer process. The final vibrational state resolved integral cross sections were found to be dominated by the quenching process Br(2P1/2) + H2(v) → Br(2P3/2) + H2(v+1) and the nonadiabatic reaction probabilities for Br(2P1/2) + H2(v = 0, 1, ji = 0) are quite small, which are consistent with previous theoretical and experimental results. Our calculated total quenching rate constant for Br(2P1/2) + H2(vi = 0, ji = 0) at room temperature is in good agreement with the available experimental data. [ABSTRACT FROM AUTHOR]

We compare the extra modes introduced by plane-wave expansion with the two-dimensional (2D) and the three-dimensional (3D) supercell approximation method, and analyze the differences between those two kinds of extra modes. In the band structure of 2D photonic crystal (PhC) using the 2D supercell approximation, the extra modes are created through band folding, and those extra modes can really exist in the 2D PhC. However, in the band structure of a 2D PhC slab using the 3D supercell approximation, the extra modes are mainly generated by the coupling between supercells, and cannot exist in the real 2D PhC slab, thus these extra modes are defined as fake modes in our paper. Through a detailed analysis of the origin of the fake modes and of the energy distribution of the fake modes and of the real modes, we propose an improved fake mode free plane-wave expansion and three planar slab waveguides method which removes the fake modes. This is the first time such a fake mode free band structure is presented. This result can be definitely helpful in designing 3D devices. [ABSTRACT FROM AUTHOR]

State-to-state photodissociation dynamics of H2O in its B band has been investigated quantum mechanically on a new set of non-adiabatically coupled potential energy surfaces for the lowest two 1A′ states of H2O, which are developed at the internally contracted multi-reference configuration interaction level with the aug-cc-pVQZ basis set. Quantum dynamical calculations carried out using the Chebyshev propagator yield absorption spectra, product state distributions, branching ratios, and differential cross sections, which are in reasonably good agreement with the latest experimental results. Particular focus is placed here on the dependence of various dynamical observables on the photon energy. Detailed analyses of the dynamics have assigned the diffuse structure in absorption spectrum to short-time recurring dynamics near the HOH conical intersection. The non-adiabatic dissociation to the ground state OH product via the HOH conical intersection is facile, direct, fast, and produces rotationally hot OH(X) products. On the other hand, the adiabatic channel on the excited state leading to the OH(Ã) product is dominated by long-lived resonances, which depend sensitively on the potential energy surfaces. [ABSTRACT FROM AUTHOR]

The three lowest (1A′, 2A′, and 1A′′) adiabatic potential energy surfaces (PESs) for the Br(2P) + H2 reactive system have been computed based on the multi-reference configuration interaction (MRCI) method including the Davidson's correction with a large basis set. These three adiabatic PESs have been transformed to a diabatic representation, leading to four coupling potentials. In addition, the spin-orbit matrix elements were also obtained using the Breit-Pauli Hamiltonian and the unperturbed MRCI wavefunctions in the Br + H2 channel and the transition state region. Consequently, six coupling potentials were obtained and their characteristics were extensively discussed. Nonadiabatic quantum dynamics calculations for this system have been realized with these realistic diabatic potentials instead of previous semi-empirical diabatic potentials. Based on two-state model nonadiabatic calculations for the Br(2P3/2, 2P1/2) + H2 reaction, the Br(2P1/2) + H2 reaction was found to show less reactivity than the Br(2P3/2) + H2 reaction at collision energies beyond the threshold of the Br(2P3/2) + H2 reaction. Our results are consistent with the previous studies on the XH2 (X = F, Cl) system, which indicate that the adiabatically forbidden channel is dominant at low energies in the open-shell halogen atom plus H2 reactions. [ABSTRACT FROM AUTHOR]

A Chebyshev-based flux-flux correlation function approach is introduced for calculating multiple initial state selected reaction probabilities for bimolecular reactions. Based on the quantum transition-state theory, this approach propagates, with the exact Chebyshev propagator, transition-state wave packets towards the reactant asymptote. It is accurate and efficient if many initial state selected reaction probabilities are needed. This approach is applied to the title reaction to elucidate the influence of the H2O ro-vibrational states on its reactivity. Results from several potential energy surfaces are compared. [ABSTRACT FROM AUTHOR]

Quantum state-to-state differential cross sections, along with the absorption spectrum and product internal state distributions, have been calculated for the photodissociation of H2O in its B band on a new set of ab initio potential energy surfaces in a diabatic representation. The theoretical attributes are in good agreement with the recent experimental data, shedding light on the non-adiabatic dissociation dynamics. [ABSTRACT FROM AUTHOR]

Quantum state-to-state dynamics for the H + HBr(υi = 0,ji =0) reaction was studied on an accurate ab intio potential energy surface for the electronic ground state of BrH2. Both the H + HBr → H2 + Br abstraction reaction and the H′ + HBr → H′Br + H exchange reaction were investigated up to a collision energy of 2.0 eV. It was found that the abstraction channel is dominant at lower collision energies, while the exchange channel becomes dominant at higher collision energies. The total integral cross section of the abstraction reaction at a collision energy of 1.6 eV was found to be 1.37 Å2, which is larger than a recent quantum mechanical result (1.06 Å2) and still significantly smaller than the experimental value (3 ± 1 Å2). Meanwhile, similar to the previous theoretical study, our calculations also predicted much hotter product rotational state distributions than those from the experimental study. This suggests that further experimental investigations are highly desirable to elucidate the dynamic properties of the title reactions. [ABSTRACT FROM AUTHOR]

A global potential energy surface (PES) for the electronic ground state of the BrH2 system was constructed based on the multireference configuration interaction (MRCI) method including the Davidson's correction using a large basis set. In addition, the spin-orbit correction were computed using the Breit-Pauli Hamiltonian and the unperturbed MRCI wavefunctions in the Br + H2 channel and the transition state region. Adding the correction to the ground state potential, the lowest spin-orbit correlated adiabatic potential was obtained. The characters of the new potential are discussed. Accurate initial state specified rate constants for the H + HBr → H2 + Br abstraction reaction were calculated using a time-dependent wave packet method. The predicted rate constants were found to be in excellent agreement with the available experimental values and much better than those obtained from a previous PES. [ABSTRACT FROM AUTHOR]

Laser waterless decontamination is a widely researched area for the high pollution issue of residual organic solvents in industry and agriculture. In this research, a nanosecond pulsed laser was used to conduct waterless decontamination studies on organic solvent residues on the surface of optical glass. A single-factor test was designed using the decontamination rate (Y) as the response value and the laser power (X 1), scanning speed (X 2), and decontamination times (X 3) as the influencing variables. The Raman spectrum reflected the decontamination effect of organic solvent decontamination using a waterless laser. The Box-Behnken response surface method (RSM) was used to design the experiments. The developed RSM was used to determine the link between laser parameters and decontamination rate, and optimum decontamination parameters were determined. In addition, the mathematical model and regression equation were established using Design-Expert. The findings demonstrate that residual solvent may be removed at a rate of up to 95.22%. Optimum values for laser power, scanning speed, and decontamination times are 130 W, 381 mm/s, and 10 times respectively. [ABSTRACT FROM AUTHOR]