Search

Microneedles (MNs) prepared from polymeric materials are painless and minimally invasive, safe and efficient, but they hindered by low mechanical strength and single diverse drug release pattern. Due to the distinctive mechanical strength and dimensions of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), the integration of nano-technology with microneedles can effectively improve penetration and delivery efficiency through the stratum corneum. We herein designed a simple paroxetine (PAX)-loaded PLGA nanoparticles-integrated dissolving microneedles system (PAX-NPs-DMNs), aiming to improve the bioavailability of PAX through the synergistic permeation-enhancing effect of dissolving microneedles (DMNs) and NPs. PAX-NPs-DMNs had a complete tips molding rate (N eff) of (94.06 ± 2.16) %, a 15×15 quadrangular-conical microneedle array and an overall fracture force of 301.10 N, which were improved nearly 0.50 times compared with the blank microneedles (HA-DMNs) and PAX microneedles (PAX-DMNs). PAX-NPs-DMNs could extend the release duration of PAX from 1 h to 24 h and the cumulative permeability per unit area (Q n) was 47.66 times and 7.37 times higher than the PAX and the PAX-DMNs groups. PAX-NPs-DMNs could be rapidly dissolved within 10 min without hindering skin healing or causing adverse reactions. This study confirmed that PAX-NPs-DMNs can effectively improve the bioavailability of PAX and the mechanical strength of DMNs, which can easily penetrate the skin to provide sustained and painless delivery without causing adverse effects, thus offering a more convenient and effective method for central nervous diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to the antioxidant properties of lignin, it has been demonstrated as an active substance for treating oxidation-related and inflammatory diseases. However, how the structural properties of lignin affect its biological activities is still ambiguous. In this study, Kraft lignin from wheat straw (KL-A) was used as the raw material to fractionate into three fractions (e.g. , KL-B, KL-C, and KL-D) with different molecular weight by ultrafiltration, which possessed different physicochemical properties. The biocompatibility, in vivo and in vitro scavenging abilities for reactive oxygen species (ROS), and anti-apoptotic abilities of the lignin fractions were evaluated using SW1353 chondrocyte cell lines and were quantitatively fitted to their physicochemical properties. The results showed that lignin fractions with lower molecular weights, lower G/S ratios, and higher non-condensed phenolic OH contents endowed lignin with stronger ROS scavenging ability in vivo and in vitro , but was accompanied by increased cytotoxicity to cells. The half maximal inhibitory concentration (IC50) of KL-A, KL-B, KL-C, and KL-D were separately determined as 44.02, 33.43, 32.41, and 18.40 μg/mL. Furthermore, KL-D, with the lowest molecular weight and highest number of functional groups, showed the best antioxidant ability, while it performed poorly in inhibiting cellular apoptosis of chondrocytes. Compared to KL-D, KL-C with inverse structural properties, performed better in anti-apoptosis of SW1353 cells, which is the optimum lignin as promising active substances to be applied in the treatment of osteoarthritis in biomedical engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

In this article, we propose the integral and differential operators within the kernel of the Y function for the first time. We study the properties of the J and Y functions. We also present the some new applications of the heat transfer and present the new representation for the solution of the heat equation in the 1-D case. [ABSTRACT FROM AUTHOR]

Flexible conductive hydrogels have great potential for healthcare and human motion sensing. However, it is difficult to simultaneously achieve conductive hydrogel epidermal sensors with reliable adhesion capabilities and excellent sensing properties, as well as accelerated wound healing performance in wearable hydrogels. Here, an epidermal sensor with excellent adhesion (0.6 kPa) and tensile strain (218.0 %) properties was assembled from an easy-to-prepare bilayer antimicrobial hydrogel, which effectively accelerates wound healing, as well as for human motion sensing. The upper hydrogel layer was composed of PVA, which could effectively enhance the mechanical properties of the bilayer hydrogel. The lower hydrogel layer consisted of polyacrylamide (PAm) and chitosan-dopamine (CC-DA). PAm with good adhesion properties adhered effectively to the skin surface. CC-DA not only had adhesion properties, but also has good antibacterial effects. It inhibited the growth of bacteria, which assisted in wound healing and infection prevention. Therefore, the design of the bilayer hydrogel combined the mechanical enhancement of PVA with the adhesion properties and antimicrobial effect of PAm and CC-DA to provide better wound repair. In addition, the double-layer hydrogel with good electrical conductivity (1.65 S·m−1) could sensitively monitor the tiny electrophysiological signals emitted by the human body during exercise rehabilitation training. [ABSTRACT FROM AUTHOR]

Flexible conductive hydrogels have great potential for healthcare and human motion sensing. However, it is difficult to simultaneously achieve conductive hydrogel epidermal sensors with reliable adhesion capabilities and excellent sensing properties, as well as accelerated wound healing performance in wearable hydrogels. Here, an epidermal sensor with excellent adhesion (0.6 kPa) and tensile strain (218.0 %) properties was assembled from an easy-to-prepare bilayer antimicrobial hydrogel, which effectively accelerates wound healing, as well as for human motion sensing. The upper hydrogel layer was composed of PVA, which could effectively enhance the mechanical properties of the bilayer hydrogel. The lower hydrogel layer consisted of polyacrylamide (PAm) and chitosan-dopamine (CC-DA). PAm with good adhesion properties adhered effectively to the skin surface. CC-DA not only had adhesion properties, but also has good antibacterial effects. It inhibited the growth of bacteria, which assisted in wound healing and infection prevention. Therefore, the design of the bilayer hydrogel combined the mechanical enhancement of PVA with the adhesion properties and antimicrobial effect of PAm and CC-DA to provide better wound repair. In addition, the double-layer hydrogel with good electrical conductivity (1.65 S·m−1) could sensitively monitor the tiny electrophysiological signals emitted by the human body during exercise rehabilitation training. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Composite conditioners can reduce NH 3 and HCN generation at each stage. • The synergy on NO x precursors reduction in homogeneous stage accounted for 50.59–98.76% of final decrement. • Nitrile-N and pyrrole-N in char converted to indole-N in tar with iron-catalyzing in heterogeneous process. • Both char-N and tar-N can be decomposed to N 2 in the existence of CaO. Abstract Fenton's reagent (Fe2+ + H 2 O 2) and CaO are the conditioners during sludge dewatering, which also showed abilities in NO x precursors control during drying and pyrolysis process that we have found before. This study further refined the effects of conditioners on homogeneous and heterogeneous processes during sludge steam gasification using a self-designed decoupling reactor. The results show that compared with raw sludge, the NH 3 and HCN yields of conditioned sludge decreased by 13.71–17.67 mL/g and 17.77–23.45 mL/g at 873–1073 K respectively. 50.59–98.76% of decrement attributed to the synergistic effect of conditioners on volatiles homogeneous reforming, owing to the less NH 3 , HCN and tar-N yields in devolatilization product as well as the indirect enhancement of HCN hydrolysis. Fenton's reagent added alone exhibited a significant effect on volatiles heterogeneous reforming. During the interaction between volatiles and char, iron salts could catalyze the nitrile-N and pyrrole-N in char conversion to stable indoles in tar and inhibited the hydrolysis of amine-N to release NH 3. Calcium salts also showed a certain capability on the co-decomposition of quaternary-N in char and indoles/quinolones in tar to harmless N 2. Thus, the combination of Fenton's reagent and CaO can complementarily reduce the emission of NO x precursors at each stage of gasification. [ABSTRACT FROM AUTHOR]

Objective. The chest computed tomography (CT) examination is an important clinical examination in the diagnosis and monitoring of paraquat- (PQ-) induced lung injury. The aim of this study was to explore the prognostic value of the average lung CT number acquired by quantitative CT techniques in patients with acute paraquat poisoning in the early stages of the disease. Methods. 46 patients who suffered from acute PQ poisoning in the emergency department of the Nanjing Drum Tower Hospital from January 2015 to June 2020 were enrolled in the present study. The patients were divided into survival group (n = 21) and nonsurvival group (n = 25). Clinical data were collected from subjects who met the inclusion criteria, including general information, personal disease history, and laboratory test indicators. The average lung CT numbers of each patient were obtained by quantitative CT techniques. Receiver operating characteristic (ROC) analysis was conducted to assess the prognostic value of average lung CT number in patients with acute paraquat poisoning. Results. The average CT numbers of the middle-lung, lower-lung, and whole lung fields in the nonsurvival group were significantly higher than those of the survival group (p < 0.0001). However, the upper-lung field was not significantly different between the two groups (p = 0.7765). The AUCs of different levels ranged from 0.554 to 0.977, among which the lower-lung field presented the largest AUC of 0.977 (95% CI: 0.943∼1; cut-off value: −702Hu; sensitivity 96%; specificity, 90.5%; YI: 0.865), followed by the whole lung field 0.914 (95% CI: 0.830∼0.999; cut-off value: −727Hu; sensitivity 76%; specificity, 95.2%; YI: 0.712) and the middle-lung field 0.87 (95% CI: 0.768∼0.971; cut-off value: −779Hu; sensitivity 80%; specificity, 85.7%; YI: 0.657). Conclusion. The present study indicated that the average lung CT number could be used to evaluate the relationship between the severity of PQ-induced lung injury and prognosis, especially in the lower-lung field. However, further research is needed to draw a clear conclusion. [ABSTRACT FROM AUTHOR]

In this paper, robust output tracking control problem of a laboratory helicopter for automatic landing in high seas is investigated. The motion of the helicopter is required to synchronise with that of an oscillating platform, e.g. the deck of a vessel subject to wave-induced motions. A robust linear time-invariant output feedback controller consisting of a nominal controller and a robust compensator is designed. The robust compensator is introduced to restrain the influences of parametric uncertainties, nonlinearities and external disturbances. It is shown that robust stability and robust tracking property can be achieved simultaneously. Experimental results on the laboratory helicopter for automatic landing demonstrate the effectiveness of the designed control approach. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the attitude tracking control problem for a three degree-of-freedom laboratory helicopter, which aims to improve tracking control performances of elevation and pitch channels. The model of each channel is considered as a linear system with equivalent disturbances which contain nonlinear uncertainties, coupling effects, parameter perturbations, and external disturbances. A state-feedback controller is applied to the linear model and a robust compensator is introduced to restrain the effects of equivalent disturbances. The robust properties of the closed-loop control system with the proposed controller are shown better than the standard controller. Experimental results demonstrate the improved performances of the proposed control strategy. [Copyright &y& Elsevier]

Robust attitude control problem for a three-degree-of-freedom (3-DOF) laboratory helicopter is investigated. The helicopter dynamics involves nonlinearity, uncertainties, and strong interaxis coupling. A robust controller is proposed with three parts: a nominal feedforward controller, a nominal linear quadratic regulation (LQR) controller, and a robust compensator. The LQR controller is applied to deal with a nominal linear error system derived by the feedforward control strategy and linearized approximation, while the robust compensator is designed to restrain the effects of uncertainties, nonlinear properties, and external disturbances. It is shown that the attitude tracking error of the closed-loop system can be guaranteed to converge to any given small neighborhood of the origin in a finite time. Experimental results on the 3-DOF laboratory helicopter demonstrate the effectiveness of the proposed control strategy. [ABSTRACT FROM PUBLISHER]

The basis of the autonomous driving system of the micro-vehicles based on simple visual is the road element detection. Based on the lack of the micro-vehicles processing capacity and the real-time requirements of the detection and control algorithms, the paper proposed a new feature extraction and tracking algorithm based on the pixel data blocks. We use the fixed OTSU threshold image binarization to reduce the impact of light. The detection experiments show that the rapid structural road elements detection(RSRED) algorithm can extract the lane markings, road signs, zebra crossings and other road elements against the interference of light, shelter, pollution and the vehicle speed definitely influence over detection rate of road elements. Finally the Lane-kepping and Overtaking experiments show that the algorithm is efficient and stable. [ABSTRACT FROM AUTHOR]

This study presents a method for a one-step co-encapsulation of PLGA nanoparticles in hydrophilic nanofibers. The aim is to effectively deliver the drug to the lesion site and achieve a longer release time. The celecoxib nanofiber membrane (Cel-NPs-NFs) was prepared by emulsion solvent evaporation and electrospinning with celecoxib as a model drug. By this method, nanodroplets of celecoxib PLGA are entrapped within polymer nanofibers during an electrospinning process. Moreover, Cel-NPs-NFs exhibited good mechanical strength and hydrophilicity, with a cumulative release of 67.74% for seven days, and the cell uptake at 0.5 h was 2.7 times higher than that of pure nanoparticles. Furthermore, pathological sections of the joint exhibited an apparent therapeutic effect on rat OA, and the drug was delivered effectively. According to the results, this solid matrix containing nanodroplets or nanoparticles could use hydrophilic materials as carriers to prolong drug release time. [ABSTRACT FROM AUTHOR]

In this article we suggest a new odd entire function of order one. We discover that it is the solution of the heat equation. We propose a new conjecture that this function has only real zeros. The obtained result gives a connection with the heat problem and number theory. [ABSTRACT FROM AUTHOR]

Abstract: The antioxidative activity of isolated peptides from of tuna cooking juice hydrolysates by orientase was determined. The results showed that, among the hydrolysates obtained under different hydrolysis time, the highest antioxidative activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity were presented at 60min. Then, the protein hydrolysate was subjected to a Sephadex G-25 gel filtration chromatography, and five major fractions were obtained. Peptide fractions ranging from 400 to 1500Da showed the highest antioxidative activity among all fractions. The peptide fractions were further isolated using the two-step high performance liquid chromatography (HPLC-1 and HPLC-2), and six and three fractions were obtained, respectively. The final three antioxidative peptides comprised 4–10 amino acids sequences were observed, and the structures of the peptides were Pro-Val-Ser-His-Asp-His-Ala-Pro-Glu-Tyr (1305Da), Pro-Ser-Asp-His-Asp-His-Glu (938Da), and Val-His-Asp-Tyr (584Da), respectively. We thus conclude that antioxidative hydrolysates from tuna cooking juice may be useful ingredients in food and nutraceutical applications. [Copyright &y& Elsevier]

Abstract: Electrical capacitance tomography (ECT) has been used to obtain the cross-section images of processes with different dielectric materials inside. Image reconstruction with ECT is to retrieve the permittivity distribution of materials inside the sensor from the capacitance measurements. Algorithms for ECT image reconstruction should be both precise and fast in order to satisfy the requirements of real-time monitoring of the dynamic behavior of processes. Several algorithms have been developed for ECT image reconstruction. The Landweber iteration is the most precise one. However, the low convergence rate of the Landweber iteration limits its application for on-line imaging. This paper introduces an iterative algorithm based on the Landweber method with preconditioning for ECT image reconstruction. A preconditioner, which is equivalent to a filter, is applied to the Landweber iteration. The convergence of this algorithm is analyzed. Its performance is evaluated by using simulated and experimental data corresponding to certain typical permittivity distributions. Preliminary numerical and experimental results show that this algorithm converges more rapidly than the Landweber iteration without preconditioning. Therefore, image reconstruction iteration can be accelerated, which makes on-line quantitative image reconstruction possible. [Copyright &y& Elsevier]

As the rapid-spreading disease COVID-19 occupies the world, most governments adopt strict control policies to alleviate the impact of the virus. These policies successfully reduced the prevalence and delayed the epidemic peak, while they are also associated with high economic and social costs. To bridge the microscopic epidemic transmission patterns and control policies, simulation systems play an important role. In this work, we propose an agent-based disease simulator for indoor public spaces, which contribute to most of the transmission in cities. As an example, we study Guangzhou Baiyun International Airport, which is one of the most bustling aviation hubs in China. Specifically, we design a high-efficiency mobility generation module to reconstruct the individual trajectories considering both lingering behavior and crowd mobility, which greatly enhances the credibility of the simulated mobility and ensures real-time performance. Based on the individual trajectories, we propose a multi-path disease transmission module optimized for indoor public spaces, which includes three main transmission paths as close contact transmission, aerosol transmission, and object surface transmission. We design a novel convolution-based algorithm to mimic the diffusion process, which can leverage the high concurrent capability of the graphics processing unit to accelerate the simulation process. Leveraging our simulation paradigm, the effectiveness of common policy interventions can be quantitatively evaluated. For mobility interventions, we find that lingering control is the most effective mobility intervention with 32.35% fewer infections, while increasing social distance and increasing walking speed have a similar effect with 15.15% and 18.02% fewer infections. It demonstrates the importance of introducing crowd mobility into disease transmission simulation. For transmission processes, we find the aerosol transmission involves in 99.99% of transmission, which highlights the importance of ventilation in indoor public spaces. Our simulation also demonstrates that without strict entrance detection to identify the input infections, only performing frequent disinfection cannot achieve desirable epidemic outcomes. Based on our simulation paradigm, we can shed light on better policy designs that achieve a good balance between disease spreading control and social costs. [ABSTRACT FROM AUTHOR]

We present a theoretical study on the spin-dependent transport through the ferromagnetic graphene nanoribbons in the presence of a magnetic and an in-plane ac electric field, and find that when the ac field is applied, in the two-terminal ferromagnetic graphene device, for the parallel configurations of the electrodes' magnetizations, the width of the even-number conductance plateaus decrease, the new conductance plateaus appear at the odd-number positions, and the even-number conductance plateaus at the high energy are quenched under the sufficiently strong ac field. In contrast, for the antiparallel configuration of the electrodes' magnetizations, the odd-plateaus of the conductance shrink, and the new plateaus developed at the even-number positions. The magnetic resistance exhibits a successive rectangular-like oscillation structure close to the band edge, whereas experiences an alternative transition between the sharp peak and dip near the zero energy with increasing the ac field strength. In the six-terminal ferromagnetic graphene device, the variations of the longitudinal and Hall resistances' plateaus as well as the addition of the new quantized plateaus with the rise of the ac field strength are also revealed. • We study magnetotransport through ac driven ferromagnetic graphene nanoribbons. • In the two-terminal device under an ac field, conductance plateaus can be transmuted into the integer plateaus sequences. • Magnetic resistance exhibits an alternative transition between the sharp peak and dip at the band center under an ac field. • In the six-terminal device, the new quantized plateaus appear in the Hall resistance. [ABSTRACT FROM AUTHOR]

Myelin abnormalities, oligodendrocyte damage, and concomitant glia activation are common in demyelinating diseases of the central nervous system (CNS). Increasing evidence has demonstrated that the inflammatory response triggers demyelination and gliosis in demyelinating disorders. Numerous clinical interventions, including those used to treat multiple sclerosis (MS), have confirmed prednisone (PDN) as a powerful anti-inflammatory drug that reduces the inflammatory response and promotes tissue repair in multiple inflammation sites. However, the underlying mechanism of PDN in ameliorating myelin damage is not well understood. In our study, a cuprizone (CPZ)-induced demyelinated mouse model was used to explore the mechanism of the protection provided by PDN. Open-field tests showed that CPZ-treated mice exhibited significantly increased anxiety and decreased exploration. However, PDN improved emotional behavior, as evidenced by an increase in the total distance traveled, and central distance traveled as well as the mean amount of time spent in the central area. CPZ-induced demyelination was observed to be alleviated in PDN-treated mice based on luxol fast blue (LFB) staining and myelin basic protein (MBP) expression analyses. In addition, PDN reduced astrocyte and microglia activation in the corpus callosum. Furthermore, we demonstrated that PDN inhibited the Nod-like receptor pyrin domain containing 3 (NLRP3) inflammasome signaling pathway and related inflammatory cytokines and chemokines, including TNF-α, CCL8, CXCL10 and CXCL16. PDN also reduced the serum corticosterone levels in the CPZ-treated mice. Taken together, these results suggest that inhibition of the NLRP3 signaling pathway may be a novel mechanism by which PDN exerts its protective actions in demyelinating diseases. [ABSTRACT FROM AUTHOR]

Formation-containment analysis and design problems for high-order linear time-invariant swarm systems with directed interaction topologies are dealt with respectively. Firstly, protocols are presented for leaders and followers respectively to drive the states of leaders to realize the predefined time-varying formation and propel the states of followers to converge to the convex hull formed by the states of leaders. Secondly, formation-containment problems of swarm systems are transformed into asymptotic stability problems, and an explicit expression of the formation reference function is derived. Sufficient conditions for swarm systems to achieve formation containment are proposed. Furthermore, necessary and sufficient conditions for swarm systems to achieve containment and time-varying formation are presented respectively as special cases. An approach to determine the gain matrices in the protocols is given. It is shown that containment problems, formation control problems, consensus problems and consensus tracking problems can all be treated as special cases of formation-containment problems. Finally, numerical simulations are provided to demonstrate theoretical results. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Robust attitude control problem for small-scale unmanned helicopters is investigated to improve attitude control performances of roll and pitch channels under both small and large amplitude manoeuvre flight conditions. The model of the roll or pitch angular dynamics is regarded as a nominal single-input single-output linear system with equivalent disturbances which contain nonlinear uncertainties, coupling-effects, parameter perturbations, and external disturbances. Based on the signal compensation method, a robust controller is designed with two parts: a proportional-derivative controller and a robust compensator. The designed controller is linear and time-invariant, so it can be easily realised. The robust properties of the closed-loop system are proven. According to the ADS-33E-PRF military rotorcraft standard, the controller can achieve top control performances. Experimental results demonstrate the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Output containment analysis and design problems for high-order linear time-invariant swarm systems are dealt with. Firstly, output containment protocols are presented for leaders and followers, respectively, to partially assign the output motion modes of leaders and propel the outputs of followers to converge to the convex hull formed by the outputs of leaders. Then, output containment problems for swarm systems are transformed into stability problems, and sufficient conditions for swarm systems to achieve output containment are proposed. Moreover, an approach to determine the gain matrix in the protocol for swarm systems to achieve output containment is given, which has less calculation complexity. Finally, numerical simulations are presented to demonstrate theoretical results. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Time‐varying formation control problems for high‐order linear time‐invariant swarm systems with switching interaction topologies are investigated. A general formation control protocol is proposed firstly. Then using a consensus based approach, necessary and sufficient conditions for swarm systems with switching interaction topologies to achieve a given time‐varying formation are presented. An explicit expression of the time‐varying formation reference function is given. It is revealed that the switching interaction topologies have no effect on the formation reference function and the motion modes of the formation reference can be specified. Furthermore, necessary and sufficient conditions for formation feasibility are presented. An approach to expand the feasible formation set is given and an algorithm to design the protocol for swarm systems with switching interaction topologies to achieve time‐varying formations is provided. Finally, numerical simulations are presented to demonstrate theoretical results. [ABSTRACT FROM AUTHOR]

As a sort of model-free tracking approach, discriminative correlation filter (DCF)-based trackers have shown prominent performance in unmanned aerial vehicle (UAV) tracking. Nevertheless, typical DCFs acquire all samples oriented to filter training merely from the current frame by cyclic shift operation in the spatial domain but ignore the consistency between samples across the timeline. The lack of temporal cues restricts the performance of DCFs under object appearance variations arising from object/UAV motion, scale variations, and viewpoint changes. Besides, many existing methods commonly neglect the channel discrepancy in object position estimation and generally treat all channels equally, thus limiting the further promotion of the tracking discriminability. To these concerns, this work proposes a novel tracking approach based on a multi-regularized correlation filter (MRCF), i.e., MRCF tracker. By regularizing the deviation of responses and the reliability of channels, the tracker enables smooth response variations and adaptive channel weight distributions simultaneously, leading to favorable adaption to object appearance variations and enhancement of discriminability. Exhaustive experiments on five authoritative UAV-specific benchmarks validate the competitiveness and efficiency of MRCF against top-ranked trackers. Furthermore, we apply our proposed tracker to monocular UAV self-localization under air–ground robot coordination. Evaluations indicate the practicability of the presented method in UAV localization applications. [ABSTRACT FROM AUTHOR]

SUMMARY Containment analysis and design problems for high-order linear time-invariant singular swarm systems on directed graphs with time delays are investigated. To eliminate impulse terms in singular swarm systems and ensure that the singular swarm systems can achieve containment, time-delayed protocols are presented for leaders and followers, respectively. By model transformation, containment problems of singular swarm systems are converted into stability problems of multiple low-dimensional time-delayed systems. In terms of linear matrix inequality, sufficient conditions are presented for time-delayed singular swarm systems to achieve containment, which are independent of the number of agents. By using the method of changing variables, an approach is provided to determine the gain matrices in the protocols. Numerical simulations are shown to demonstrate theoretical results. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study presents a controller design method to achieve the robust attitude control for uncertain quadrotors. The proposed linear time‐invariant controller consists of a proportional–derivative (PD) controller and a robust compensator. The PD controller is designed for the nominal linear system to achieve the desired tracking and the robust compensator is added to restrain the influence of the uncertainties. It is proven that attitude tracking errors are bounded and the boundaries can be made as small as desired. Experimental results on the quadrotor are given to confirm the effectiveness of this control method. [ABSTRACT FROM AUTHOR]

Abstract: A digital imaging based method for measuring the velocity of pneumatically conveyed particles is described in this paper. The measurement system consists of a laser sheet for illumination, a CCD camera for particle image acquisition, and bespoke image processing software. By controlling the exposure time of the camera, blurred images of moving particles are captured, which contain velocity information of the particles. The relationship between the motion blur length and the particle velocity is established using a lens model of the camera. To improve the robustness of the system to noise in the acquired particle images, a traveling wave equation (TWE) method is used to estimate the motion blur length and then deduce the particle velocity. In addition to computer simulations experimental work on a free fall particle flow rig and pneumatically conveying test rig is carried out. The results indicate that the proposed method is feasible for the velocity measurement of pneumatically conveyed particles. [Copyright &y& Elsevier]

Abstract: Image reconstruction for electrical capacitance tomography (ECT) is to retrieve the permittivity distribution of materials inside the sensor from the capacitance measurements outside. It is a typical inverse problem and has long been a challenge for its nonlinearity and ill-posedness. This paper discusses the application of Tikhonov regularization, widely used for ill-posed problems, to the image reconstruction for electrical capacitance tomography. Two methods using different regularizations are investigated, which are the standard Tikhonov regularization and the Tikhonov regularization based on the second order derivative operator. Particularly, a combined method using the linear back projection (LBP) result as the prior constraint for the Tikhonov regularization with the second order derivative operator is suggested. Simulation and experiment results show that this combined method takes advantages from both the linear back projection and the Tikhonov regularization and provides reconstructions better than those from the LBP and the Tikhonov regularization. In addition, considering the essence that the Tikhonov regularization can be described as a spectral filter characterized by its corresponding window function, we propose the possibility of applying other window functions to the ECT image reconstruction, which include the Gauss window, the Hanning window, the Blackman window, and the cosine window. Results also show the feasibility of using window functions as regularization, which presents a new strategy for the regularization of ECT image reconstruction. [Copyright &y& Elsevier]

Due to its low molecular weight and abundant functional groups, water-soluble lignin (WSL) is considered as a more potent antioxidant than traditional industrial lignin in biofields. However, few studies have been conducted to evaluate its intracellular and endogenous reactive oxygen species (ROS)-scavenging ability, especially for the intervention of ROS-related disease in vivo. In this work, WSL in bamboo autohydrolysate (WSL-BM) and wheat stalk autohydrolysate (WSL-WS) were isolated and characterized to comparably analyze their bioactivities. The composition analysis and NMR characterization showed that both WSL-BM and WSL-WS contained relatively similar components and substructures, but WSL-BM contained higher contents of phenolic OH groups. Both WSL samples exhibited excellent biocompatibility with the concentration below 50 μg/mL, while WSL-BM exhibited superior ROS-scavenging ability and ROS-related ulcerative colitis treatment potential at same concentration. In addition, WSL-BM also showed better performance in ameliorating inflammation and oxidative stress in RAW 264.7 cells and colitis mice by activating Nrf2 and suppressing NFκB signaling, resulting in an overall improvement in both macroscopic and histological parameters. Overall, these results implied that WSL from gramineous biomass can be used as a novel anti-inflammatory and antioxidative agent in the biomedical field. This work shows the application of water-soluble lignin (WSL) extracted from bamboo (BM) and wheat stalk (WS) as as a bioactivator (anti-inflammatory and antioxidative) for ulcerative colitis. [Display omitted] [ABSTRACT FROM AUTHOR]

The research on cable crosstalk is an important part of electromagnetic compatibility. The conventional research on cable crosstalk is mostly for parallel cables. However, most of the actual transmission line models are in a non-parallel state. A new method for the crosstalk prediction of coplanar irregular-placed cables is proposed in this paper. The method derives the integral form of the transmission line equation based on the cascade method. Combined with the cubic spline interpolation method for the processing of the per unit length parameter matrix, the crosstalk of the coplanar irregular-placed cables is predicted. The orthogonal experiment method is used to find that the distance between transmission lines has the greatest influence on crosstalk, followed by height from the current return plane, frequency, load and length. In order to verify the accuracy of the new method for crosstalk, the full wave method is introduced as a comparison method, and the experiment is introduced as a reference method. The verification results show that the new method has higher accuracy for the crosstalk prediction of coplanar irregular-placed cables, especially in the frequency band less than 100MHz. [ABSTRACT FROM AUTHOR]

The radar cross section (RCS) of seaskimming unmanned aerial vehicle (UAV) can be influenced by the sea surface scattering under different sea conditions. In this paper, a composite model of the rough sea surface and sea-skimming UAV is established. A hybrid algorithm based on the application of physical optics (PO) method and improved multilevel fast multipole algorithm (PO-IMLFMA) for solving the RCS of the composite model based on four-path model (FPM) is proposed. Compared with multilevel fast multipole algorithm (IMLFMA) and PO and method of moment (PO-MOM), PO-IMLFMA has the advantages of less memory consumption (about 295 MB) and faster solution speed (about 768 s) for solving the composite model. Furthermore, in view of the influence of sea surface on the RCS of sea-skimming UAV, a compensation scheme based on back propagation (BP) neural network for the RCS of UAV is proposed. The compensation scheme is analyzed for the monostatic RCS of sea-skimming UAV under different sea conditions. The compensation results show that the compensation errors under 1-scale, 3-scale and 5-scale sea conditions are less than 0.95 dBsm, 0.41 dBsm and 1.94 dBsm, respectively. In other words, the compensation scheme significantly reduces the influence of sea conditions. [ABSTRACT FROM AUTHOR]

Calorimetric measurements are performed to determine the specific heat of Si-x at.% Ge (where x = 0, 10, 30, 50, 70, 90 and 100) alloys within a broad temperature range from 123 to 823 K. The measured specific heat increases dramatically at low temperatures, and the composition dependence of specific heat is evaluated from the experimental results. Meanwhile, the specific heat at constant volume, the thermal expansion, and the bulk modulus of Si and Ge are investigated by the first principle calculations combined with the quasiharmonic approximation. The negative thermal expansion is observed for both Si and Ge. Furthermore, the isobaric specific heat of Si and Ge is calculated correspondingly from 0 K to their melting points, which is verified by the measured results and accounts for the temperature dependence in a still boarder range. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fenton/CaO-treated sludge gasification ash is used as adsorbent. • The sludge gasification ash shows the best H 2 S and NH 3 adsorption performance at 1173 K. • The CaO conditioned ash with better pore structures boosts the SO 2 adsorption performance. • The conversion of H 2 S to sulfate and sulfide is improved by iron-calcium compounds. • The adsorption of NH 3 mainly depended on the acid sites carbon structures at 873 K. Abstract Gasification technology can effectively convert the organic substances to combustible gas, but the high content of inorganic matter in sludge will cause a large amount of gasification ash needed to be utilized remaining. On the basis of our previous study, Fenton's reagent (Fe2+/H 2 O 2) and CaO conditioning brought more Fe- and Ca-containing compounds, providing the potential for gasification ash as adsorbent. This study explored the mechanism of sludge gasification ash sorbent for sulfur and nitrogen containing pollutants removal. Conditioned sludge was gasified in a lab-scale fixed bed at 873 and 1173 K, then SO 2 , H 2 S and NH 3 adsorption experiments were conducted in a self-designed reactor to evaluate in situ adsorption capacity of gasification ash. According to the results, gasification ash was more suitable for the adsorption and degradation of H 2 S and NH 3 at high temperature with outlet concentration reaching the minimum of 14 and 30 ppm respectively. Iron substances can promote the surface structure of ash, while the surface area pretreated with CaO was increased twice as large as that of raw sludge ash, which can partly explain the SO 2 adsorption performance. The raw sludge gasification ash mainly promoted the decomposition of H 2 S to sulfur, while the iron and calcium salts in gasification ash converted H 2 S to sulfides and sulfates cooperatively. As for NH 3 , the adsorbents also showed great removal effect at 873 K, mainly depending on the carbon structure and surface Lewis acid sites measured by in situ FTIR. With temperature increasing, the catalytic effect of calcium and iron compounds, which can react with NH 3 to form intermediates, played a dominant role in the decomposition of NH 3. [ABSTRACT FROM AUTHOR]

• An LC-MS/MS-based MRM method was developed to measure plasma 7-KC. • Patients with sepsis and septic shock showed high plasma 7-KC expression. • High plasma 7-KC level was associated with poor prognosis in sepsis. • A prognostic model for sepsis is proposed and validated. Early evaluation of the severity of sepsis and estimation of its prognosis remains one of the main challenges in current therapeutic strategies. This study aimed to evaluate the prognostic value of plasma 7-ketocholesterol (7-KC) in sepsis. We retrospectively measured by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) the plasma 7-KC concentration in 176 patients with sepsis and 90 healthy volunteers. A multivariate Cox proportional hazard model was introduced to identify independent factors, including plasma 7-KC and clinical features, for the 28-day mortality of sepsis, and a nomogram for predicting the 28-day mortality of sepsis was established. Decision curve analysis (DCA) was performed to assess the prediction model of death risk of sepsis. The area under the curve (AUC) of plasma 7-KC in diagnosing sepsis was 0.899 (95% CI = 0.862–0.935, P < 0.001), while it was 0.830 (95% CI = 0.764–0.894, P < 0.001) in diagnosing septic shock. The AUCs of plasma 7-KC in predicting the survival of sepsis patients in the training cohort and the test cohort were 0.770 (95% CI = 0.692–0.848, P < 0.05) and 0.869 (95% CI = 0.763–0.974, P < 0.05), respectively. In addition, high plasma 7-KC expression predicts poor prognosis in sepsis. Then, 7-KC and platelet count were identified as the two factors with significant differences by a multivariate Cox proportional hazard model, and the 28-day mortality probability ranged from 0.002 to 0.985 and was assessed using a nomogram. DCA results revealed that the combination of plasma 7-KC and platelet count showed the best prognostic efficiency of the risk threshold compared to a single factor in both the training cohort and test cohort. Collectively, the elevated plasma 7-KC level is an indicator of sepsis and was identified as a prognostic indicator for sepsis patients, providing a landscape for predicting survival in early sepsis with potential clinical utility. [ABSTRACT FROM AUTHOR]

The process of sewage sludge steam gasification can be divided into three stages: devolatilization, volatiles homogeneous reforming and heterogeneous catalyzing. This study investigated the direct and indirect impacts of Fe/Ca-based conditioners on syngas generation at different stages using a special decoupling reactor. The results show that the highest H 2 production for raw sludge gasification was 190 mL/g at 1273 K. The maximum promotion of H 2 yield was 51.2% for Fenton's reagent (Fe 2+ +H 2 O 2 ) addition at 1273 K and 132.5% for CaO addition at 1073 K. Among that, 52.8% and 62.9% of H 2 increment was attributed to the catalytic effect on devolatilization stage respectively. Fenton oxidation was conducive to the conversion and fixation of protein structure while the corresponding organic matter in CaO-conditioned sludge was aromatics. The catalysis of volatile reforming was proven an important process, thus reusing char/ash as bed material or cracking catalysts maybe a promising method for hydrogen energy production. [ABSTRACT FROM AUTHOR]

In order to control the emissions of NO x precursors during sewage sludge pyrolysis, we proposed a novel integrated pretreatment method based on Fenton peroxidation and CaO conditioning. Nitrogen transformation was investigated using a self-designed drop-tube/fixed-bed furnace, and the mechanism of influence of residual conditioners was further clarified by employing model compounds. According to the results, the conversion of sludge- N to gas- N at 873–1273 K was strengthened by composite conditioning during the pyrolysis process. The remaining iron salts prevented some nitrogenous organic matter from deamination, whereas calcium compounds promoted the decomposition of proteins and amine to release NH 3 . Active iron atoms derived from an Fe-bearing conditioner reacted with NH 3 through the formation of Fe α N. Furthermore, combined conditioning hampered the conversion of amine- N /pyridine- N , pyrrole- N and nitrile- N to HCN, therefore enhancing their yields in char. The residual Ca compounds, which presented as Ca(OH) 2 , facilitated the hydrolysis of HCN and hampered HCN generation from amine- N , nitrile- N and heterocyclic- N in tar. Both residual iron and calcium conditioners were capable of reacting with protein- N in sludge and char to form Fe α N and CaC x N y , respectively. The formation of complex Ca 2 Fe 2 O 5 facilitated the decomposition of these intermediates, thus facilitating the conversion of sludge- N and NOx precursors (tar- N , NH 3 , HCN) to N 2 , achieving a highest non-polluting gas yield of 80.5%. [ABSTRACT FROM AUTHOR]

Based on an open exactly solvable system coupled to an environment with nontrivial spectral density, we connect the features of quantum and classical correlations with some features of the environment, initial states of the system, and the presence of initial system–environment correlations. Some interesting features not revealed before are observed by changing the structure of environment, the initial states of system, and the presence of initial system–environment correlations. The main results are as follows. (1) Quantum correlations exhibit temporary freezing and permanent freezing even at high temperature of the environment, for which the necessary and sufficient conditions are given by three propositions. (2) Quantum correlations display a transition from temporary freezing to permanent freezing by changing the structure of environment. (3) Quantum correlations can be enhanced all the time, for which the condition is put forward. (4) The one-to-one dependency relationship between all kinds of dynamic behaviors of quantum correlations and the initial states of the system as well as environment structure is established. (5) In the presence of initial system–environment correlations, quantum correlations under local environment exhibit temporary multi-freezing phenomenon. While under global environment they oscillate, revive, and damp, an explanation for which is given. [ABSTRACT FROM AUTHOR]

In order to achieve the complete utilization of both sludge organic and inorganic components, this study proposed a novel method for synchronous production of clean syngas and ash adsorbent during steam gasification process based on composite conditioning. Sewage sludge was pretreated by Fenton’s reagent (Fe 2+ /H 2 O 2 ) and CaO, then gasified in a lab-scale fluidized bed at 873–1273 K. The ash adsorption performance was also evaluated in a self-designed reactor. According to the results, both residual iron and calcium salts were able to promote H 2 -rich fuel gas generation. The effect of iron compounds became more strongly with temperature increased, while the influence of calcium substances tend to be more obviously with temperature decreased. Thus after combined conditioning, very good sludge gasification performance and the highest cold gas efficiency were achieved at a wide temperature range. Moreover, separate gasification of Fenton-oxidized or CaO-treated sludge released H 2 S emission respectively from sulfonic acid/sulfone/heterocyclic-S and inorganic sulfide in char. However, H 2 S releasing amount was less than 1.8% of total sulfur with the co-usage of two conditioners due to oxidation and fixation reactions. Meanwhile, although CaC x N y that formed in CaO-added sludge char reacted with steam to produce NH 3 , the residual iron and calcium compounds could synergistically inhibit the final emissions of NH 3 and HCN. In this case, no nitrogenous gas was generated at 1273 K. Besides this outstanding role, the remaining conditioners were still able to boost the adsorption performance of sludge gasification ash and significantly prolong its life. [ABSTRACT FROM AUTHOR]

A novel non-visual vibration shape reconstruction method based on orthogonal curvilinear net is proposed in paper for shape detection and reconstruction of plate structure. Its iteration process is deduced and analyzed. A high precision experimental verification platform is constructed. Real time experiments are done for pure bending deformation, torsional deformation and dynamic vibration. Reconstruction precision and performance is compared with the modal approach using displacement-strain transformation techniques. Experimental results show that the proposed method and the modal approach have good shape reconstruction performance for the static deformation with large amplitude and dynamic low frequency vibration. The reconstruction precision of the proposed algorithm was higher than modal approach for deformation with small amplitude. But the modal approach is better for dynamic high frequency vibration. The reconstruction efficiency of the proposed algorithm is superior to the modal approach. [ABSTRACT FROM AUTHOR]

• Fenton-CaO promoted As accumulation, detoxification and stabilization in sludge. • Fenton-CaO induced As oxidation/demethylation by two-step reaction in dewatering process. • FeOOH and CaO promote As oxidation by catalyzing/directly reacting with it in drying process. • Fe-bound As was less stable than Ca-bound As in char gasification stage of sludge. • All the As in gasification ash existed in the form of As(V). In sludge disposal, Arsenic (As) poses serious secondary pollution due to its high toxicity and low stability. This work systematically studied the effects of Fenton-CaO composite conditioning on As chemistry throughout sludge dewatering, thermal drying, and steam gasification processes. The experimental results showed that, for raw sludge, 40.9% of As was released with filtrate discharging and 26.8–57.3% emitted with flue gas emission. When sludge was conditioned by Fenton-CaO, all of the As in the filtrate was fixed in the sludge cake and the releasing rate of gaseous As was reduced by up to 86.0%. Furthermore, the comprehensive results of the model compounds experiment, sequential extraction, and thermodynamic calculations revealed the effects of Fe/Ca conditioners on As species evolution. In the Fenton pre-oxidation, As(V) was reduced to As(III) due to the decreasing Eh caused by the excessive Fe(II). After adding CaO, As(III)/DMA (dimethyl arsenic) was adsorbed onto the surface of amorphous Fe(OH) 3 that was introduced by Fenton's reagent, 50% and 43% of which were then oxidized or demethylated to form As(V)/MMA (monomethyl arsenic), respectively. In the following drying process at 120–180 °C, the FeOOH and CaO derived by residual Fe/Ca conditioners could promote the oxidation of 30% of the rest As(III) by the catalytic effect or directly reacting with it. In the final steam gasification process, the very little As(III) left in the dry sludge was released with the gas phase and the proportion of As(V) in gasification ash almost reached 100%. In short, Fenton-CaO composite conditioning could achieve the near-zero emission of As and reduce the toxicity of the products throughout the whole sludge treatment process. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: The thermo-sensitive genic male sterility (TGMS) of Brassica napus facilitates reproductive researches and hybrid seed production. Considering the complexity and little information about the molecular mechanism involved in B. napus TGMS, comparative transcriptomic analyses were peroformed for the sterile (160S-MS) and fertile (160S-MF) flowers to identify potential crucial genes and pathways associated with TGMS. Results: In total, RNA-seq analysis showed that 2202 genes (561 up-regulated and 1641 down-regulated) were significantly differentially expressed in the fertile flowers of 160S-MF at 25 °C when compared the sterile flower of 160S-MS at 15 °C. Detailed analysis revealed that expression changes in genes encoding heat shock proteins, antioxidant, skeleton protein, GTPase and calmodulin might be involved in TGMS of B. napus. Moreover, gene expression of some key members in plant hormone signaling pathways, such as auxin, gibberellins, jasmonic acid, abscisic acid, brassinosteroid signalings, were significantly surppressed in the flowers of 160S, suggesting that these genes might be involved in the regulation in B. napus TGMS. Here, we also found that transcription factor MADS, NFY, HSF, MYB/C and WRKY might play a crucial role in male fertility under the high temperature condition. Conclusion: High temperature can significant affect gene expression in the flowers. The findings in the current study improve our understanding of B. napus TGMS at the molecular level and also provide an effective foundation for male fertility researches in other important economic crops. [ABSTRACT FROM AUTHOR]