bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Robust Adaptive Intelligent and Compound Control of an Adaptive Neural Network, SMC, FLC and PI for Robot Manipulators
Authors: Vu Duc Ha , Huang Shoudao , Tran Thi Diep
Published: November 2019

In this paper, a new compound control scheme is proposed for robot manipulators (RMs) based on radial basis function neural network (RBFNNs), sliding mode control (SMC), fuzzy logic control (FLC) and proportional–integral (PI) controller. In this control scheme, the filtered tracking error is the input of the RBFNNs update laws, SMC, FLC and PI controller. The RBFNNs uses three-layer to approximate uncertain nonlinear manipulator dynamics. A robust sliding function is selected as a second controller to guarantee the stability and robustness under various environments. The FLC as the third controller completely removes the chattering signal caused by the sign function in the SMC. By using additional PI controllers, the goal of RMs tuning is to minimize tracking performance and overshoot can be realized. Simulation results highlight performance of the controller to compensate the approximate errors and its simpleness in the adaptive parameter tuning process. To be concluded, the controller is suitable for robust adaptive intelligent control and can be used as supplementary of traditional neural network (NN) controllers.
Preparation and study of chemical functional materials for wet mixed mortar
Authors: Zhang X F , Fang Y H , Ke Y L , Zhong S L N , Lai H Z , Guo S Y Q , Ma X X
Published: November 2019

The wet mixed mortar chemical functional material PC-2 was synthesized by monomers including 4-hydroxybutyl vinyl ether polyoxyethylene ether, acrylic acid, 4-vinylbenzenesulfonic acid and mono-2-(methacryloyloxy)ethyl succinate.The effects of different side chain lengths, the dosage of 4-vinylbenzenesulfonic acid and mono-2-(methacryloyloxy)ethyl succinate on the properties of wet-mixed mortar chemical functional materials were investigated. It had been verified by test that compared with PC-1, PC-2 could effectively reduce the consistency loss rate of wet mixed mortar, improved the water retention rate of wet mixed mortar, the tensile bond strength of 14d and the compressive strength of 7d and 28d. In the process of pumping and spraying construction, PC-2 had better performance and coud meet the requirement of continuous supply.
Research on Long-distance Non-contact Surface Defect and Crack Detection System in Civil Engineering Structures
Authors: Li Zhang , Linglong Zhou
Published: November 2019

Cracks are the result of excessive internal stress released by concrete materials. Cracks reduce the peak stress of the section. Therefore, the deformation energy stored in the structure is lower than a certain limit. Reducing the internal deformation energy by cracking is the inherent characteristic of concrete materials. Many concrete structures will have different degrees and forms of cracks, which is a quite common phenomenon. Cracks have become a common disease of concrete structures, which has long been a technical problem for construction engineers. Traditional crack detection methods of concrete bridges can not meet the needs of modern bridge detection. Based on this, this paper presents a long-distance non-contact surface defect and crack detection system, which is an economical and effective new method for bridge disease detection. This paper analyses the working principle and workflow of the detection system.
Practical Exploration of Virtual Simulation Experiment Teaching of Ceramic Art Design
Authors: Jing Chen
Published: November 2019

With the continuous development of network technology in China, the teaching of ceramic art design needs the application of new technology and equipment. The application effect of virtual simulation technology in ceramic art design teaching is remarkable. It is a new trend of experimental teaching reform to introduce virtual simulation technology into experimental teaching of higher education. This paper expounds the reform ideas and concrete methods of virtual simulation experiment teaching of ceramic art design from the aspects of characteristic virtual simulation experiment resources construction, virtual simulation experiment teaching methods and evaluation system construction, and provides a new idea for the development of ceramic experiment teaching informatization.
Effect of different blending ratio of waste polypropylene hybrid fiber on crack resistance of recycled concrete beams
Authors: Pei Chang-chun , Cui Xian , Chi Cui-ping
Published: November 2019

In order to improve the reuse efficiency of construction waste, industrial waste and textile waste, this study mixed the waste polypropylene fiber with polyacrylonitrile fiber in a certain proportion, and studied the influence of different blending ratio of hybrid fiber on crack resistance of recycled concrete beams. The experimental results showed that the mixing of hybrid fibers not only improves the basic mechanical properties and strength of recycled concrete test blocks, but also effectively inhibits the generation and development of cracks, and improves the crack resistance of recycled concrete beams. The article proposes the formula of maximum crack width in the limit state of normal use of hybrid fiber recycled concrete beams by theoretical analysis.
Molecular Behavior of Different Polycarboxylate Superplasticizers
Authors: Li Geli , Fang Yunhui , Wu Chuandeng , Guo Yuanqiang , Ma Xiuxing
Published: November 2019

Four different types of polycarboxylic superplasticizers were synthesized by using different macromonomers, and then the molecular behavior of GPC, infrared, nuclear magnetic, cement hydration heat and micromorphology were characterized. The results showed that different types of PCEs have different molecular behaviors. The research showed that the molecular weight and molecular weight distribution of PCE1 were the smallest, and these four different types of PCEs have better molecular weight and molecular weight distribution. The infrared spectra of the four PCEs were not much different. However, by 1H NMR, the macromonomer used in PCE1 when synthesised was MPEG. The macromonomer used in PCE2 and PCE4 when synthesised were TPEG, and the macro monomer used in PCE3 was HPEG. Cement hydration heat and scanning electron microscope data showed that PCE4 has the better early strength.
Study on Modification Technology of High Calcium Ash Steel Slag Composite Based on Microstructure Characteristics
Authors: Yan Zhou , Hao Zhang
Published: November 2019

By means of physicochemical modification technology, mineral admixture particles adhere to the surface of high calcium ash particles. On the one hand, mineral admixtures play a role of grinding aids, on the other hand, mineral admixtures are uniformly dispersed and closely contacted with high calcium ash particles. It is conducive to the hydration reaction of high calcium ash particles and reduces the most probable pore distribution and porosity. Active calcium oxide has a high content and contains a certain amount of self-hardening minerals. The single modification method of chemical admixtures can not effectively exert the chemical excitation effect of chemical admixtures on the activity of high calcium ash. High calcium ash and steel slag have great potential for utilization in cement concrete, and their full utilization is beneficial to environmental protection, energy saving and obtaining certain economic benefits. High calcium ash and steel slag admixture technology have achieved certain results. However, it is necessary to further study the activity of high calcium ash and steel slag in the fluctuation range of raw materials. And applied to the preparation of high durability gelation blending amount.
Performance-based Piezoelectric Material Applied in Health Inspection of Civil Engineering Structures
Authors: Xu Li , Zhang Liang
Published: November 2019

The application of piezoelectric impedance principle in health monitoring of civil engineering structures has attracted more and more attention. In this paper, the application of piezoelectric materials in health detection of civil engineering structures is reviewed. The basic principles, research progress, advantages and problems of impedance method and wave method are analyzed. Civil engineering structures, such as dams, bridges, high-rise buildings, etc., will inevitably suffer some damage during their service. Sometimes it is caused by natural factors of force majeure, or due to long-term accumulation damage, these damages will directly cause structural resistance to decay, and in severe cases may lead to catastrophic accidents. The support role of structural monitoring technology is needed to provide early warning of these disasters. Piezoelectric materials, piezoelectric impedance principles, interaction models of piezoelectric materials with monitored structures, and monitoring techniques based on impedance information. The research results of piezoelectric material size selection, scanning frequency selection, sensing range, binder influence, data acquisition equipment development and data processing methods are summarized.
Research and design of new type photovoltaic vacuum insulation cup
Authors: Zhang Shiqi , Ning Xiaoqiu , Ding Kaining , Guo Meiqi , Wang Lidi
Published: November 2019

Aiming at the problem of limited insulation time of vacuum insulating cup, the modification and design of new photovoltaic vacuum insulating cup are completed, including selection of heating material, selection of power supply of photovoltaic insulating cup, power transmission and overall structure design. Compared with similar research, this paper focuses on the selection of heating materials and the use of wireless transmission devices to solve the problem of thermal insulation. In this paper, the structure of photovoltaic insulating cup is studied, and the optimum heating material is discussed. Combined with photovoltaic power supply and wireless power transmission technology, the design of insulation Cup is completed, and the insulation performance of this design is verified for more than ten hours.
Infrared temperature spectrum analysis of air conductor considering vibration factor
Authors: Yu Xiangyang , Zhao Yuliang , Yao Linghong , Zhao Shi , Lingu
Published: November 2019

Through the analysis of the thermal state model of the wire, it is considered that the temperature rise is the characteristic parameter to measure the working state of the wire, which is related to the actual heat dissipation coefficient and heat dissipation surface area, and is determined by practical factors such as laying mode, operating current and thermal load, and external working condition. A method to determine its thermal state by obtaining infrared temperature spectrum is proposed, and the relatively stable temperature rise is taken as the evaluation index. The vibration condition promotes the establishment of heat exchange and its equilibrium. Different laying methods have different sensitivity to vibration and thermal stress.
Research on innovative design of mountain bike fender
Authors: Hua Yinhong
Published: November 2019

Based on the analysis of the insufficient of existing mountain bike fenders, the type of mountain bike tires and the use environment of mountain bike fender, combined with the design of color and material application, This paper makes a theoretical discussion on the innovative design of the mountain bike fender, and has carried on the constructive design, which solves the problems such as single shape, poor stability and imperfect function of mountain bike fender, and has practical value and guiding significance in actual product development.
Effect of mixing time of coupling agent on properties of 3D printing prototype of fly ash filled ABS
Authors: Xuan Ye , Huajin Tu , Zhiwen Qiu
Published: November 2019

Fly ash was modified by being mixed with silane coupling agent for 10min, 20min, 30min, 40min and 50min. Pure ABS, compounded materials consisting of unmodified and modified fly ash and ABS were extruded into filaments. 3D printed specimens were manufactured with extruded filaments. Results show, ABS filaments have good 3D printing process and product performance and unmodified fly ash is harmful to ABS filaments. To improve interface bonding between ABS and fly ash, silane coupling agent can be introduced, and mixing it with fly ash for 30min may be a better choice, which has better dimension stability, impact strength and tensile strength.
Estimation Requiring Torque of Prosthetic Screw by Finite Element Analysis and Experiment
Authors: Zhang Xiao , He Jingyan , Feng Wei , Chen Xianshuai
Published: November 2019

The purpose of the study was to find the influence of screw tightening torque to the prosthetic screw and screw-retained abutment-implant complex in long-term using. In this study, a method of FEM simulation is presented to estimate a suitable tightening torque of prosthetic. Torsion test has been carried out to find the ultimate torque secondly. The results of experimental are compared with simulation ones and shows a good agreement. A FEM modelling of occlusal loading with considering tightening torque is performed to investigate the influence of tightening torque under external loading subsequently. And the safety factor of 107 cycles is calculated based on the present modelling to judge the reliability in long-term using. The result shows that tightening torque not only affect the stress of prosthetic screw significantly but also the stress of screw-retained abutment. According to the study, a tightening torque less than 18N⋅cm is recommended to use ensure the functionality of implant system.
Influences of mandrel types on forming quality of TA18 high strength tube in numerical control bending
Authors: Fang Jun , Lu Shiqiang , Liang Chuang , Cheng Lu , Zheng Deliang
Published: November 2019

In order to improve the forming quality and limit of tube numerical control (NC) bending, it is necessary to select reasonable mandrel types. A finite element (FE) model of the whole process of TA18 high strength tube in NC bending was established based on the platform of ABAQUS, and its reliability was validated. Then, using the model, the effects of no mandrel, cylindrical mandrel, hemispherical mandrel and ball-and-socket mandrel on the distribution of tangential stress/strain, wall thinning and cross section distortion were studied. The results show that the shape, size and location of the tangential stress/strain distribution have no obvious difference for the NC bending without mandrel and with three mandrel types. For the bending without mandrel, the wall thinning is the smallest, and the cross section distortion is the largest, which exceeds the requirement of aviation standard. Three types of mandrel have no significant effect on the wall thinning, while the hemispherical mandrel is the most conducive to control the cross section distortion.
Application of Mesofacies Analysis Technology in Lithologic Reservoir Prediction
Authors: Guangying Hong
Published: November 2019

As an effective technique for exploration and development of lithologic reservoirs, curves and logging facies of several exploration wells and development wells in the facies analysis area were analyzed and sedimentary interpretation was carried out. Based on the analysis of well logs in the study area, this paper concluded that the main sedimentary facies in the study area are delta plain and fore-delta. It is concluded that the study area has experienced the sedimentary evolution process and sedimentary law of delta front, delta plain and delta front. It is pointed out that sedimentary micro-facies are the main oil and gas reservoir. Finally, the distribution and regularity of oil and gas enrichment areas are studied.
Research on Key Technologies of Intelligent Seeding Robot Based on Zigbee Network
Authors: Ying Wang , Kai Liang , Qi Liu , Shuo Li , Yao Gou , Baohua Li , Jinran Liu
Published: November 2019

Aimed at the problems of slow seeding speed, inaccurate path tracking and low efficiency of domestic intelligent seeding robot. An intelligent seeding robot based on Zigbee network is proposed. Wireless sensor and Zigbee network technology are combined to obtain real-time environmental data in the working area and transmit it to the robot for seeding operation. The incremental PID control method corrected by digital compass is adopted to control the robot to walk in a straight line and the ant colony algorithm is adopted to realize the path planning of the intelligent seeding robot. It solves the problem of seeding robot effectively and makes intelligent seeding robot widely used.
Kernel Adaptive Filtering Multiple-model Actuator Fault Diagnostic For Multi-effectors Aircraft
Authors: Zhu Peng , Dong Wenhan
Published: November 2019

In the traditional Multiple Model Adaptive Estimation (MMAE) algorithm, the extended Kalman filter has theoretical limitations, and the establishment of accurate aircraft mathematical model is almost impossible. In this paper, the Kernel Adaptive Filter (KAF) is introduced to replace the Kalman filter, a new multi-model adaptive estimation fault diagnosis method is proposed. Based on the kernel methods, the adaptive filter is designed in the high-dimensional feature space without the need to know the system model in advance. After training of KAF using the offline input control signal and output flight states measurement with noise, the estimation of real flight states values and actuator fault detection and isolation can be realized online. The simulation results show good performance of new fault diagnosis method in actuator fault diagnosis.
A self-calibration method for gyro scale factor asymmetry in rotational inertial navigation system
Authors: Yu Y S , Lv Y H , Wang L , Liu Z J
Published: November 2019

In the rotational inertial navigation system (RINS), the inertial measurement unit (IMU) rotates around the motor shaft, which will stimulate the gyro scale factor asymmetry, so it needs to be effectively calibrated and compensated. In this paper, the influence of gyro scale factor asymmetry on angular velocity error, angle error and velocity error is analysed, and a self-calibration method for it is proposed in the RINS using velocity errors as measurements. A self-calibration rotation strategy is designed for the dual-axis RINS so as to carry out self-calibration for the scale factor asymmetry of x-gyro, y-gyro and z-gyro. The feasibility of this scheme is verified by theoretical analysis and simulation. Experiments are carried out on a set of dual-axis RINS based on fiber optic gyroscope, and the scale factor asymmetry calibration results of three gyros are 2.56 ppm, 10.01 ppm and 0.88 ppm, respectively. In the navigation experiment, the navigation error is improved by 57.45% after compensating the gyro scale factor asymmetry error, which fully illustrates the significance of the proposed self-calibration method in improving the navigation performance of RINS.
Analysis and Design of Magnetic Levitation and Mechanical Spring Compound Vibration Isolation Control System
Authors: Dong Weihua , Zhai Mingda , Li Xiaolong
Published: November 2019

In this paper, the magnetic levitation and mechanical spring compound vibration isolation control system is designed by applying maglev active control on the basis of mechanical vibration isolator. The system can effectively solve the problems of fixed structure parameters and poor environmental adaptability of passive vibration isolators, and can be applied to the anti-vibration protection of precision instruments in complex environments. This paper analyses the mechanism and characteristics of maglev vibration isolation, deduces the dynamic model of the system, discusses the design of the active vibration isolation control strategies, and carries out several simulation experiments of vibration isolation in different environments. The results show that the design scheme of the system is reasonable and feasible.
Application of Lock-in Amplifier Technique in AC FSM based on AD630
Authors: Duan Rujiao , Meng Xiangji , Yang Yong , Sun Ming , Chen Jinzhong , Wang Haitao
Published: November 2019

Field Signature Method (FSM) is one of non-intrusive technique for pipeline internal corrosion monitoring, but the commercial FSM systems nowadays are all using DC input which have many shortcomings. In this paper, AC FSM based on AC input has been developed, DC FSM can be replaced by AC FSM with low-frequency. To extract weak signals, the lock-in amplifier based on AD630 has been designed and manufactured, the functions and designed circuits of each part have been proposed. Experimental results show that, the application of lock-in amplifier technique in AC FSM based on AD630 can measure the weak signal from the noise interference effectively, ensuring the accuracy and security at the same time.
Deep Learning Based Circuit Breaker Non - Full - Phase Operation State Monitoring Method
Authors: Tao Tao
Published: November 2019

To solve the problem of low accuracy of the traditional monitoring method, a deep learning based monitoring method is designed. A sensor is installed at the part that may cause the circuit breaker to run in non-full phase and the state data of the circuit breaker is collected through the sensor. Filter and digital-to-analog converter are used to reduce noise and digital-to-analog conversion of the signal transmitted by the sensor. After the data are standardized and normalized, input into the convolutional neural network. The parameters and weights of convolutional neural network are determined by training the sample data. After the training of convolutional neural network, the input neural network data are processed according to the determined parameters and weights. Output the processed results to the database, in the database classification algorithm after the data classification, sent to the circuit breaker operation control module, to achieve the circuit breaker operation status monitoring. Through the comparison with the traditional monitoring methods, it is verified that the designed deep learning-based state monitoring method has higher accuracy and can make up for the shortcomings of the traditional methods.
An enhanced heat collector design and numerical simulation for solar chimney power plant
Authors: Fu Shijun
Published: November 2019

The solar chimney power plant (SCPP) is a promising renewable energy technology to address energy security and CO2 mitigation problems. To improve efficiency of energy conversion from solar radiation to electricity, this article changes conventional horizontal heat collector and proposes a partial inclined and convergent collector for SCPP. Utilizing k – ε turbulence model and computational fluid dynamics (CFD) method, this article implemented a series of numerical simulations to explore the thermodynamic characteristics of airflow in SCPP and power generation efficiency in a way of changing value of design parameters, such as collector convergent angle, slope length and collector radius. The results reveal that, increasing these parameters will decrease airflow pressure, increase airflow velocity and temperature around the chimney base, hence will improve power generation efficiency. Comparing the enhanced convergent collector with conventional horizontal one, the former can improve SCPP performance and energy transformation efficiency.
A Research on Electric Inertia Simulation Technology Based on AC Induction Motor
Authors: Li Bo , Wang Weina
Published: November 2019

In order to study the application of AC induction motor in electrical inertia simulation system, a simulation model of electrical inertia simulation system was established by MATLAB/Simulink. The closed-loop vector control strategy of the drive motor and load motor torque of the system is proposed after analyzing the theory of electrical inertia simulation. The angular acceleration of the system during acceleration and deceleration is obtained by approximation based on the system rotation speed measured. Thus, the automatic compensation of the inertia torque of the load motor is realized. A mechanical inertia disk was simulated. According to the results of the simulation, the speed error of the electric inertia simulation system is within 15 r/min, which indicates that this method can realize accurate inertia simulation.
Joint optimal dispatch of electric vehicles and air conditioning loads in office buildings based on demand response
Authors: Yang Jie , Zhang Ruiping , Dong Haiying
Published: November 2019

Centralized use of air conditioning loads and the disordered charging and discharging of large-scale electric vehicles in cities have become the important reason for peak-valley difference increase of grid load in summer, deepening the contradiction between supply and demand during the peak period. Therefore, it is of great significance to improve power grid load characteristic and realize stable and economic operation of power grid by excavating peak shaving potential of large-scale air conditioning loads and electric vehicles. Taking into account the dispatching cost of power grid companies and the benefits of power users, a joint optimal dispatching model of electric vehicle and air-conditioning load is proposed. The power grid provided a low price compensation for loads and a high price compensation for EVs due to its battery loses. The objective function is optimized with the minimum load difference rate of office buildings and the maximum total revenue of users. Analysis of calculation example shows that air conditioning load and electric vehicle have complementary characteristics in energy use, and the joint optimal dispatching has certain effect on office building "peak load reduction", eliminating "secondary peak load" and improving electricity user income.
Computing weighted value of the fast linear iterations distributed consensus algorithm based on label propagation algorithm
Authors: Huanxin Peng , Bin Liu
Published: November 2019

In order to accelerate the convergence rate of distributed consensus under complex topology, the fast linear iterations distributed consensus algorithm was proposed by Xiao L. the fast linear iterations distributed consensus algorithm improved dramatically the convergence rate of the distributed consensus problem, but computing the weighted value was difficult, and the computing volume geometrically increased with the expansion of the communication topology. In the paper, the weighted value of every node was computed based on label propagation algorithm. In the paper, firstly, the complex network was divided into a few communities by the label propagation algorithm, the nodes between different community were weighted. The analysis and simulation of computing volume and the convergence speed were done. The computing volume of the proposed method was smaller than that of the fast linear iterations distributed consensus algorithm.
Weighted distributed consensus algorithm based on label propagation algorithm
Authors: Huanxin Peng , Bin Liu
Published: November 2019

In the practical application of multi-agent system, the convergence rate of the distributed consensus algorithm becomes slow with the expansion of the communication topology. In order to accelerate the convergence rate of distributed consensus under complex topology, in the paper, based on the fast linear iterations distributed consensus algorithm, a weighted distributed consensus algorithm based on label propagation algorithm was proposed. In the algorithm, firstly based on label propagation algorithm, the complex topology was composed into two layer of topologies, in the first layer of topology, the information was exchange each other within the same community, in the second layer of topology, the information was exchange within the different communities . The consensus firstly was reached in the first layer of topology, then the consensus was reached in the second of layer topology. The analysis and simulation of the convergence performance and the convergence speed were done. The results show that the average consensus can be reached in the weighted distributed consensus, and the convergence rate of the proposed algorithm was higher than that of the fast linear iterations distributed consensus algorithm.
Accelerating the convergence rate of distributed consensus algorithm based on label propagation algorithm
Authors: Bin Liu , Huanxin Peng
Published: November 2019

In order to accelerate the convergence rate of distributed consensus problem under complex topology, in the paper, the distributed consensus algorithm based label propagation algorithm was proposed. Firstly, we composed the complex topology into two layer of topologies by label propagation algorithm, the first layer of topology was consist of a few small communities, and every small community was considered as a node of the second layer of topology. The consensus firstly was reached in the first layer topology, then the consensus was reached in the second layer topology. In the paper, the convergence performance of the algorithm was proved. The analysis and simulation on convergence rate were done, the results show the convergence rate of the algorithm was higher than that of the usually first-order distributed consensus algorithm.
The Impact of Cultural Exchange between China and South Korea on the Relations between the Two Countries in the Internet Era
Authors: Hong Sun
Published: November 2019

Based on a clear understanding of the current situation of cultural exchanges between China and Korea, this paper focuses on the impact of contemporary cultural exchanges on the politics, economy, trade and society of China and Korea, and then expounds the problems arising from cultural exchanges between China and Korea, as well as the measures to be taken in the face of future cultural exchanges between the two countries, so as to guide the development of Sino-Korean relations in the direction beneficial to the common interests of the two peoples, to establish a comprehensive partnership strategy between China and Korea, to promote the smooth development of Sino-Korean relations, and to bring enlightenment to better play the role of cultural exchanges in promoting the relations between the two countries in the future.
Synchronization Control of Switched Complex Networks with Additive Delays
Authors: Sun Changfan , Lu Guoping , Sheng Suying , Dai Xinglei
Published: November 2019

The synchronization control problem for a class of switched complex networks with additive time-varying delays is studied.Firstly,the switched complex network drive-response system for system node parameter switching is studied.The appropriate Lyapunov function is constructed under the influence of additive time delay.According to Lyapunov stability theory and inequality technique,the sufficient conditions for mean-square exponential synchronization of the system are obtained.And these conclusions are expressed by linear matrix inequality (LMI).Secondly,the matrix inequality is solved by using LMI toolbox to synchronize the master-slave system.Finally,a numerical example is given to verify the effectiveness of the proposed method.
Lyapunov function selection for saturated constrained system
Authors: Zhang Cui
Published: November 2019

For a nonlinear system which is not globally asymptotically stable, it is important to study its attractive domain. Saturation constrained control system is one of the most important nonlinear systems. The estimation of attractive domain of saturated constrained control system involves the selection of Lyapunov function. This paper summarizes the different Lyapunov functions in the estimation of attractive domain of saturated constrained control system and illustrates them with numerical examples.
Characterization and corrosion resistance study of the Fe–Cr films electrodeposited from trivalent chromium sulfate electrolyte
Authors: Niu Yongkang , Zhang Shasha , Cheng Qian , Zhang Zelei , Yao Zhengjun , Moliar Oleksandr
Published: November 2019

Fe–Cr alloy films were prepared by direct current electrodeposition using trivalent chromium sulfate electrolyte. The reaction process was clarified by cyclic voltammetry and the influence of the deposition voltage on the characteristics of the alloy was investigated by GIXRD, SEM and AFM. The chemical composition of the surface passivation film was analyzed by XPS. The corrosion performance of Fe–Cr alloy films was analyzed by Tafel polarization curves and AC impedance spectra. The results show that the electrodeposition process mainly involves the reduction process of Fe2+ and Cr3+ under glycine complexation, accompanied by hydrogen evolution reaction at high deposition voltage. The deposition voltage has obvious effect on the crystallographic structure, morphology and composition of the alloy films. Compact and uniform amorphous Fe–Cr films can be obtained at a deposition voltage of 1.9 V and the content of Cr reaches 40%. A comparison of the corrosion potential, corrosion current and polarization resistance for the deposits indicates that the Fe–Cr alloy film prepared at deposition voltage 1.9 V have superior corrosion resistance. The main chemical composition of the passivation film is Cr2O3, CrO3, which contribute to its excellent corrosion resistance.
Stress signalling dynamics of the mitochondrial electron transport chain and oxidative phosphorylation system in higher plants
Authors: Dourmap Corentin , Roque Solène , Morin Amélie , Caubrière Damien , Kerdiles Margaux , Béguin Kyllian , Perdoux Romain , Reynoud Nicolas , Bourdet Lucile , Audebert Pierre-Alexandre , Moullec Julien Le , Couée Ivan
Published: November 2019

Background

Mitochondria play a diversity of physiological and metabolic roles under conditions of abiotic or biotic stress. They may be directly subjected to physico-chemical constraints, and they are also involved in integrative responses to environmental stresses through their central position in cell nutrition, respiration, energy balance and biosyntheses. In plant cells, mitochondria present various biochemical peculiarities, such as cyanide-insensitive alternative respiration, and, besides integration with ubiquitous eukaryotic compartments, their functioning must be coupled with plastid functioning. Moreover, given the sessile lifestyle of plants, their relative lack of protective barriers and present threats of climate change, the plant cell is an attractive model to understand the mechanisms of stress/organelle/cell integration in the context of environmental stress responses.

Scope

The involvement of mitochondria in this integration entails a complex network of signalling, which has not been fully elucidated, because of the great diversity of mitochondrial constituents (metabolites, reactive molecular species and structural and regulatory biomolecules) that are linked to stress signalling pathways. The present review analyses the complexity of stress signalling connexions that are related to the mitochondrial electron transport chain and oxidative phosphorylation system, and how they can be involved in stress perception and transduction, signal amplification or cell stress response modulation.

Conclusions

Plant mitochondria are endowed with a diversity of multi-directional hubs of stress signalling that lead to regulatory loops and regulatory rheostats, whose functioning can amplify and diversify some signals or, conversely, dampen and reduce other signals. Involvement in a wide range of abiotic and biotic responses also implies that mitochondrial stress signalling could result in synergistic or conflicting outcomes during acclimation to multiple and complex stresses, such as those arising from climate change.
Current challenges and best-practice protocols for microbiome analysis
Authors: Bharti Richa , Grimm Dominik G
Published: November 2019

Analyzing the microbiome of diverse species and environments using next-generation sequencing techniques has significantly enhanced our understanding on metabolic, physiological and ecological roles of environmental microorganisms. However, the analysis of the microbiome is affected by experimental conditions (e.g. sequencing errors and genomic repeats) and computationally intensive and cumbersome downstream analysis (e.g. quality control, assembly, binning and statistical analyses). Moreover, the introduction of new sequencing technologies and protocols led to a flood of new methodologies, which also have an immediate effect on the results of the analyses. The aim of this work is to review the most important workflows for 16S rRNA sequencing and shotgun and long-read metagenomics, as well as to provide best-practice protocols on experimental design, sample processing, sequencing, assembly, binning, annotation and visualization. To simplify and standardize the computational analysis, we provide a set of best-practice workflows for 16S rRNA and metagenomic sequencing data (available at https://github.com/grimmlab/MicrobiomeBestPracticeReview).
Multivessel percutaneous coronary intervention with bifurcation stenting in a quadfurcated single coronary artery from the right aortic sinus: a case report
Authors: Al Jarallah Mohammed , Rajan Rajesh , Kotevski Vladimir , Dashti Raja , Moustafa Wagdy
Published: November 2019

Background

Quadfurcation of single coronary artery (SCA) from the right is an extremely rare anomaly and acute coronary syndrome in such patients is catastrophic.

Case summary

We report a 56-year-old Bangladeshi male who presented with an acute inferior wall ST-elevation myocardial infarction. He was taken to the Cath lab for primary percutaneous coronary intervention which showed the presence of SCA arising from the right aortic sinus with multiple lesions including a bifurcation lesion. Percutaneous coronary intervention was done successfully in two sessions.

Discussion

Tackling multiple lesions in a case of SCA with quadfurcation was challenging especially in the setting of SCA and bifurcation lesions. This is first reported case of this kind.
The Rhododendron Genome and Chromosomal Organization Provide Insight into Shared Whole-Genome Duplications across the Heath Family (Ericaceae)
Authors: Soza Valerie L , Lindsley Dale , Waalkes Adam , Ramage Elizabeth , Patwardhan Rupali P , Burton Joshua N , Adey Andrew , Kumar Akash , Qiu Ruolan , Shendure Jay , Hall Benjamin
Published: November 2019

The genus Rhododendron (Ericaceae), which includes horticulturally important plants such as azaleas, is a highly diverse and widely distributed genus of >1,000 species. Here, we report the chromosome-scale de novo assembly and genome annotation of Rhododendron williamsianum as a basis for continued study of this large genus. We created multiple short fragment genomic libraries, which were assembled using ALLPATHS-LG. This was followed by contiguity preserving transposase sequencing (CPT-seq) and fragScaff scaffolding of a large fragment library, which improved the assembly by decreasing the number of scaffolds and increasing scaffold length. Chromosome-scale scaffolding was performed by proximity-guided assembly (LACHESIS) using chromatin conformation capture (Hi-C) data. Chromosome-scale scaffolding was further refined and linkage groups defined by restriction-site associated DNA (RAD) sequencing of the parents and progeny of a genetic cross. The resulting linkage map confirmed the LACHESIS clustering and ordering of scaffolds onto chromosomes and rectified large-scale inversions. Assessments of the R. williamsianum genome assembly and gene annotation estimate them to be 89% and 79% complete, respectively. Predicted coding sequences from genome annotation were used in syntenic analyses and for generating age distributions of synonymous substitutions/site between paralgous gene pairs, which identified whole-genome duplications (WGDs) in R. williamsianum. We then analyzed other publicly available Ericaceae genomes for shared WGDs. Based on our spatial and temporal analyses of paralogous gene pairs, we find evidence for two shared, ancient WGDs in Rhododendron and Vaccinium (cranberry/blueberry) members that predate the Ericaceae family and, in one case, the Ericales order.
Serotonin regulates maternal calcium homeostasis during the perinatal period of sheep
Authors: Jin Lu , Nameiriga  , Sun Haizhou , Dan Sang , Li Shengli , Zhang Chongzhi , Zhang Chunhua , Ren Xiaoping , Shan Dan , Ling Shuli
Published: November 2019

The goal of this experiment was to demonstrate the ability of an infusion of serotonin (5-HT; 5-hydroxytryptamine) precursors to increase 5-HT production during the transition from pregnancy to lactation and its effects on gene expression related to calcium (Ca) transporters in the mammary gland and bone resorption markers in the femur. Thirty pregnant Bamei mutton sheep were randomly assigned to 3 experimental groups. All groups received a daily intravenous infusion of saline (control group; n = 10), saline containing 0.178 mg of L-tryptophan/kg body weight (BW) (TRP group, n = 10) or 0.178 mg of 5-hydroxytryptophan/kg BW (5-HTP group, n = 10), beginning on day 7 of prepartum and continuing until delivery. Serum (pre- and postpartum), milk (postpartum), and femur and mammary gland tissue (day 9) were collected. Sheep infused with 5-HTP had a larger total serum Ca concentration on days 3, 6, 15, and 30 of lactation and total milk Ca concentration on days 3, 6, 12, and 15 of lactation compared with that of the control group. Sheep infused with 5-HTP and TRP increased blood and milk concentrations of 5-HT on days 3, 6, 9, and 30 of lactation and parathyroid hormone-related protein (PTHrP) on day 3 of prepartum and on days 3, 6, and 15 of lactation (P < 0.05). In addition, compared to that of the control group, the TRP or 5-HTP infusion upregulated PTHrP, a sodium/calcium exchanger, plasma membrane Ca2+ ATPase 2, secretory pathway Ca2+ ATPase 1, and calcium sensing receptor mRNA expression in mammary gland and receptor-activated nuclear factor kappa-B ligand mRNA expression in the femur, but had no effect on receptor-activated nuclear factor kappa-B and osteoprotegerin mRNA expression in the femur (P < 0.05). This suggests that 5-HT and PTHrP may be involved in regulating maternal Ca homeostasis during the transition from pregnancy to lactation in the sheep.
Peri-operative pain management in hip arthroscopy: a systematic review of the literature
Authors: Kolaczko Jensen G , Knapik Derrick M , Salata Michael J
Published: November 2019

The purpose of this article was to review current literature on peri-operative pain management in hip arthroscopy. A systematic review of the literature on pain control in hip arthroscopy published January 2008 to December 2018 was performed. Inclusion criteria consisted of English language or articles with English translations, subjects undergoing hip arthroscopy with documented peri-operative pain control protocols in studies reporting Level I to IV evidence. Exclusion criteria were non-English articles, animal studies, prior systematic review or meta-analyses, studies not reporting peri-operative pain control protocols, studies documenting only pediatric (<18 years of age) patients, studies with Level V evidence and studies including less than five subjects. Statistical analysis was performed to assess pain protocols on narcotic consumption in PACU, VAS score on discharge, time to discharge from PACU and incidence of complications. Seventeen studies were included, comprising 1674 patients. Nerve blocks were administered in 50% of patients (n = 838 of 1674), of which 88% (n = 740 of 838) received a pre-operative block while 12% (n = 98 of 838) post-operative block. Sixty-eight complications were recorded: falls (54%, n = 37), peripheral neuritis (41%, n = 28), seizure (1.5%, n = 1), oxygen desaturation and nausea (1.5%, n = 1) and epidural spread resulting in urinary retention (1.5%, n = 1). No significant differences in narcotic consumption, VAS score at discharge, time until discharge or incidence of complication was found based on pain control modality utilized. No statistically significant difference in PACU narcotic utilization, VAS pain scores at discharge, time to discharge or incidence of complications was found between peri-operative pain regimens in hip arthroscopy.
Flying while pregnant: what is the thrombosis risk?
Authors: Vethanayagam Bahy , Kahn Susan R
Published: November 2019

Physicians are encouraged to risk stratify pregnant and post-partum travelers into low, intermediate and high risk for venous thromboembolism. In the average healthy pregnant or postpartum woman, the risk of travel-associated venous thromboembolism appears low (< 1%), warranting only routine, common sense preventive measures. However, higher risk women may warrant thromboprophylaxis.
Unbiased Estimation of Linkage Disequilibrium from Unphased Data
Authors: Ragsdale Aaron P , Gravel Simon
Published: November 2019

Linkage disequilibrium (LD) is used to infer evolutionary history, to identify genomic regions under selection, and to dissect the relationship between genotype and phenotype. In each case, we require accurate estimates of LD statistics from sequencing data. Unphased data present a challenge because multilocus haplotypes cannot be inferred exactly. Widely used estimators for the common statistics r2 and D2 exhibit large and variable upward biases that complicate interpretation and comparison across cohorts. Here, we show how to find unbiased estimators for a wide range of two-locus statistics, including D2, for both single and multiple randomly mating populations. These unbiased statistics are particularly well suited to estimate effective population sizes from unlinked loci in small populations. We develop a simple inference pipeline and use it to refine estimates of recent effective population sizes of the threatened Channel Island Fox populations.
HDAC inhibition induces expression of scaffolding proteins critical for tumor progression in pediatric glioma: focus on EBP50 and IRSp53
Authors: Capdevielle Caroline , Desplat Angélique , Charpentier Justine , Sagliocco Francis , Thiebaud Pierre , Thézé Nadine , Fédou Sandrine , Hooks Katarzyna B , Silvestri Romano , Guyonnet-Duperat Veronique , Petrel Melina , Raymond Anne-Aurélie , Dupuy Jean-William , Grosset Christophe F , Hagedorn Martin
Published: November 2019

Background

Diffuse midline glioma (DMG) is a pediatric malignancy with poor prognosis. Most children die less than one year after diagnosis. Recently, mutations in histone H3 have been identified and are believed to be oncogenic drivers. Targeting this epigenetic abnormality using histone deacetylase (HDAC) inhibitors such as panobinostat (PS) is therefore a novel therapeutic option currently evaluated in clinical trials.

Methods

BH3 profiling revealed engagement in an irreversible apoptotic process of glioma cells exposed to PS confirmed by annexin-V/propidium iodide staining. Using proteomic analysis of 3 DMG cell lines, we identified 2 proteins deregulated after PS treatment. We investigated biological effects of their downregulation by silencing RNA but also combinatory effects with PS treatment in vitro and in vivo using a chick embryo DMG model. Electron microscopy was used to validate protein localization.

Results

Scaffolding proteins EBP50 and IRSp53 were upregulated by PS treatment. Reduction of these proteins in DMG cell lines leads to blockade of proliferation and migration, invasion, and an increase of apoptosis. EBP50 was found to be expressed in cytoplasm and nucleus in DMG cells, confirming known oncogenic locations of the protein. Treatment of glioma cells with PS together with genetic or chemical inhibition of EBP50 leads to more effective reduction of cell growth in vitro and in vivo.

Conclusion

Our data reveal a specific relation between HDAC inhibitors and scaffolding protein deregulation which might have a potential for therapeutic intervention for cancer treatment.