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In the present study, an improved method for single-fiber compression sample preparation and compressive strength experiments is developed. This method improves the experiment efficiency and accuracy of the obtained results. Two improvements over the previous studies were implemented. Firstly, a special device is provided to improve the efficiency of compression specimen preparation using a mini-motor control platform. Secondly, an improved device for measuring the compressive strength of a single fiber is developed and verified using the results of analysis of four carbon fibers. More than 75 high-quality specimens were obtained compared to only one specimen when using the previous method. Compression tests of four types of carbon fibers that were used in our previous study were performed again using the improved device. Our results show good agreement with previous results, which indicates the validity of the two devices used for measuring the compressive strength of single fibers. [ABSTRACT FROM AUTHOR]

Wheat ( Triticum aestivum L.) morphological and adaptation-related traits that are controlled by quantitative trait loci (QTLs) help define potential growing areas of a wheat cultivar. To dissect QTLs for heading date, lodging, shattering (SH), cold tolerance, plant height, spike length, spike compactness, awn length (AL) and chaff color (CC), a high-density genetic map with single nucleotide polymorphism and simple sequence repeat markers were developed using recombinant inbred lines (RILs) derived from 'Ning7840' × 'Clark'. The RILs were evaluated in eight Oklahoma environments from 2001 to 2004. A total of 31 QTLs with additive effects on different traits were mapped on most wheat chromosomes except for 1D, 3A, 3D, 4D, 6D, and 7B. Six chromosome regions showed either tightly linked QTLs or QTLs with pleiotropic effects for two to three traits. Five QTL pairs showed additive × additive effects (AA). Ten additive QTLs were involved in additive × environment (AE) effects, and one epistatic QTL was involved in AAE effects. Among nine traits evaluated only three (SH, AL, and CC) were controlled by single genes in this biparental population. Seven traits were conditioned by multiple QTLs. A total of 127 markers were tightly linked to the QTLs. The findings shed light on the inheritance of wheat morphological and adaptation-related traits and provide DNA markers for manipulating these important traits to improve wheat production. [ABSTRACT FROM AUTHOR]

Background: Asthma is a heterogenetic disorder characterized by chronic inflammation with variable airflow obstruction and airway hyper-responsiveness. As the most potent and popular bronchodilators, β2 adrenergic receptor (β2AR) agonists bind to the β2ARs that are coupled via a stimulatory G protein to adenylyl cyclase, thereby improving cAMP accumulation and resulting in airway smooth muscle relaxation. We previously demonstrated arctigenin had a synergistic function with the β2AR agonist, but the target for this remained elusive. Method: Chemical proteomics capturing was used to enrich and uncover the target of arctigenin in human bronchial smooth muscle cells, and reverse docking and molecular dynamic stimulation were performed to evaluate the binding of arctigenin and its target. In vitro enzyme activities and protein levels were demonstrated with special kits and Western blotting. Finally, guinea pig tracheal muscle segregation and ex vivo function were analysed. Results: Arctigenin bound to PDK1 with an ideal binding free energy 25.45 kcal/mol and inhibited PDK1 kinase activity without changing its protein level. Additionally, arctigenin reduced PKB/Akt-induced phosphorylation of PDE4D, which was first identified in this study. Attenuation of PDE4D resulted in cAMP accumulation in human bronchial smooth muscle. The inhibition of PDK1 showed a synergistic function with β2AR agonists and relaxed the constriction of segregated guinea pig tracheal muscle. Conclusions: The PDK1/Akt/PDE4D axis serves as a novel asthma target, which may benefit airflow obstruction. [ABSTRACT FROM AUTHOR]

Fan Gao,1 Wen-Tao Zhang,2 Ya-Yun Lin,2 Wei-Min Wang,2 Na Xu,2 Gui-Qin Bai2 1Clinical Research Center, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710061, People’s Republic of China; 2Department of Gynecology and Obstetrics, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710061, People’s Republic of ChinaCorrespondence: Gui-Qin BaiDepartment of Gynecology and Obstetrics, The First Affiliated Hospital of Xi’an Jiaotong University, 277 Yanta West Road, Xi’an, Shaanxi 710061, People’s Republic of ChinaTel +86-18991232517Email baigq@126.comPurpose: To investigate whether tenofovir disoproxil fumarate (TDF) treatment that started from the second trimester had an advantage over TDF treatment that started from the third trimester.Patients and methods: Twenty 35-year-old pregnant women with hepatitis B virus (HBV) DNA >2×106 IU/mL were prospectively enrolled in this study. All participants were divided into two subgroups: the second trimester group who started TDF treatment at 24–27 weeks and the third trimester group who started TDF treatment at 28–30 weeks. The primary outcome was the change in serum HBV DNA level from baseline to delivery. Each parameter was tested every 4 weeks from TDF initiation to 3 months postpartum.Results: There were 80 pregnant women in the second trimester group and 49 pregnant women in the third trimester group. The decline in HBV DNA from baseline to delivery was more obvious in the second trimester group (4.8±1.2 log10 IU/mL) than that in the third trimester group (4.3±1.1 log10 IU/mL, p=0.041). The downward shift of haemoglobin (HB) from baseline to delivery was greater in the second trimester group (10.6±10.7 g/L) than in the third trimester group (6.3±12.3 g/L, p=0.041). The decline in HBV DNA from baseline to delivery was linearly related to the start of TDF treatment from the second trimester (β=0.50 and 95% CI: 0.26–0.75, p

Ferroelectric oxide nanocrystals, in combination with the robust coupling of an electric field with crystal structure symmetry, makes such systems agreeable to field-induced crystal structural transformation. The luminescent properties of rare earth ions are sensitive to the symmetry of the surrounding crystal field. The luminescence tuning of rare earth ions is an important assignment in the research of luminescent materials. However, the current conditional feasibility and reversibility in the exploration of luminescence modification remain major challenges. In this article, the luminescence modulation of rare earth ions has been developed in Yb3+/Er3+ codoped ferroelectrics glass ceramics containing Bi4Ti3O12 nanocrystals through an electric field. The inclusion of nanocrystals in the glass matrix greatly enhances the electrical resistance. Both upconversion and near-infrared emissions of rare earth ions are effectively enhanced more than twice via polarization engineering. The electric field regulates the photonic properties of rare earth ions with excellent reversibility and nonvolatility in ferroelectrics. The effective modification by electric field provides a new scheme for optical storage and optoelectronic devices.

The miniature pig possesses unmatched advantages as an animal model because of its high homology with humans. Our experiment aimed to build a chronic renal failure (CRF) model in pigs via laparoscopy.

In megacities, the number of vehicles has rapidly grown. Automatic parking, a special type of unmanned driving, has become an important technology to ease parking difficulties. Path tracking is also a core part of automatic parking. However, during automatic parking, the curvature of the reference path is very large. This poses a challenge in automatic parking and is different from that in high-speed unmanned driving. When the curvature of the reference path is large, the constraints of the system severely restrain the path tracking performance. These constraints include the limit of the steering wheel angle speed. Applying model predictive control is a good way to handle multiple constraints. Recently, a path tracking controller for automatic parking based on linear time-varying model predictive control has been reported. However, for automatic parking, the accuracy of the linearized prediction model is still insufficient. To solve this problem, a path tracking controller based on nonlinear model predictive control was proposed in this paper. This controller was compared with the controller based on linear time-varying model predictive control. The simulation environment is a combination of MATLAB/Simulink and PreScan. The simulation results show that the proposed controller could complete automatic parking with multiple constraints. After the parking was completed, the angle between the vehicle heading and the center line of the parking space was 0.0189 rad. The distance between the midpoint of the rear axle of the vehicle and the center line of the parking space was 0.1045 m. This distance was only 5.56% of the width of the vehicle body. Compared with the controller based on linear time-varying model predictive control, the proposed controller for automatic parking exhibited a higher parking precision, larger safety margin, and less parking time. In terms of real-time performance, the proposed controller could also meet the requirements for automatic parking.

Due to the narrow roadway and poor working environment, underground mines pose a threat to the safety of vehicle drivers. The realization of automatic driving of underground mine vehicles can improve mining automation and intelligence and ensure safety of workers, and it can significantly increase mining and exploitation efficiency. Automatic driving of underground mining vehicles requires the technologies of location, communication, navigation, and path following control. Automatic driving of mining vehicles is the ultimate approach of autonomous navigation and auto driving, while path following control system is one of the core technologies of the autopilot system. The path following control system is a multi-variable, multi-constraint system. There are optimization problems under multiple constraints as well as challenges such as actuator saturation during the control process. To solve the above problems, a model predictive control method was introduced in this paper. By considering the relationship between the position and situation of the vehicle, the objective function of the predictive control was optimized by minimizing the lateral deviation of the following path and the heading angle deviation of the vehicle. Therefore, the optimal controls of vehicle speed and articulation angle were obtained, and the problem of multi-variable and multi-constraint system was solved. For the tracking overshoot problem caused by the inability of determining sudden changes of road curvature in the model predictive control strategy, a control method based on preview distance was proposed; thus, the vehicle path following control accuracy and stability was improved through the advance judgment of road mutation information. Matlab/Adams simulation software was used to perform a comparison simulation test. The results show that the model predictive following controller is capable of solving the control problem in multi-variable, multi-constrained system and effectively prevent the actuator saturation. Moreover, the model predictive following control strategy based on the preview distance keeps the horizontal deviation of the vehicle within ±0.04 m and the heading angle deviation within ±1.8°. Compared with the controller before improvement, the lateral position deviation is reduced by 80.9%, and the heading angle deviation is reduced by 59.1%; this proves that the improved controller has better lateral stability and accuracy.

Aiming at the technical defects of the existing helium mass-spectrometry leak detection system, a design and implementation of the helium mass spectrometry leak detection system based on the Internet of Things technology is proposed. The system integrates embedded system, WiFi，ZigBee and consists of main control module, acquisition module and execution module. The main control module can integrate the data information of the helium mass spectrometer leak detector and the acquisition module. The execution module automatically completes the leak detection process, and predicts the stable time of the leak detection signal by gray algorithm, which can improve the leak detection efficiency. The test results show that the implementation scheme is effective.

The inconsistency among the battery cells for electric vehicle affects the performance and life expectancy of the batteries. A mixed optimal control scheme based on capacity balance and voltage balance is proposed. The scheme gives priority to capacity balance, as well as combines with the voltage balance, which makes full use of the advantages of these schemes. In addition, through the practical experiment, especially for lithium iron phosphate battery, it is proved that this strategy achieved higher efficiency and better effect than the traditional balance scheme- voltage equilibrium. This strategy can greatly improve the inconsistency among the battery cells and boost the battery capacity.

In order to optimize the control method of guide vane opening in an adjustable hydraulic torque converter, this paper presents a variable universe fuzzy control method for servo system of the adjustable hydraulic torque converter based on the multi-population genetic algorithm. This control method got a kind of adaptive control as optimizing proportional exponential contraction-expansion factors of the current loop with a genetic algorithm, thus transforming the fuzzy variable universe of the current loop. In this method, we designed a variable universe adaptive fuzzy controller with S-function on an adjustable hydraulic torque converter servo system and conducted some simulation experiments. The simulation results showed that the variable universe control based on genetic algorithm improved the anti-interference and robustness of adjustable hydraulic torque converter servo system compared with control methods in the previous literature. This control method could be a desirable way to adjust guide vane opening with the properties of better accuracy, rapidity, and reliability. Thus, the control method we designed will provide an effective, fast, and stable control strategy for the uncertain system with the properties of nonlinearity, strong disturbance, and uncertain time-varying.