Polymorphisms in Epigenetic and Meat Quality Related Genes in Fourteen Cattle Breeds and Association with Beef Quality and Carcass Traits

Improvement for carcass traits related to beef quality is the key concern in beef production. Recent reports found that epigenetics mediates the interaction of individuals with environment and nutrition. The present study was designed to analyze the genetic effect of single nucleotide polymorphisms (SNPs) in seven epigenetic-related genes (DNMT1, DNMT3a, DNMT3b, DNMT3L, Ago1, Ago2, and HDAC5) and two meat quality candidate genes (CAPN1 and PRKAG3) on fourteen carcass traits related to beef quality in a Snow Dragon beef population, and also to identify SNPs in a total of fourteen cattle populations. Sixteen SNPs were identified and genotyped in 383 individuals sampled from the 14 cattle breeds, which included 147 samples from the Snow Dragon beef population. Data analysis showed significant association of 8 SNPs within 4 genes related to carcass and/or meat quality traits in the beef populations. SNP1 (13154420A>G) in exon 17 of DNMT1 was significantly associated with rib-eye width and lean meat color score (pG) of DNMT3a was significantly associated with six beef quality traits. Those individuals with the wild-type genotype AA of DNMT3a showed an increase in carcass weight, chilled carcass weight, flank thicknesses, chuck short rib thickness, chuck short rib score and in chuck flap weight in contrast to the GG genotype. Five out of six SNPs in DNMT3b gene were significantly associated with three beef quality traits. SNP15 (45219258C>T) in CAPN1 was significantly associated with chuck short rib thickness and lean meat color score (p<0.05). The significant effect of SNP15 on lean meat color score individually and in combination with each of other 14 SNPs qualify this SNP to be used as potential marker for improving the trait. In addition, the frequencies of most wild-type alleles were higher than those of the mutant alleles in the native and foreign cattle breeds. Seven SNPs were identified in the epigenetic-related genes. The SNP15 in CAPN1 could be used as a powerful genetic marker in selection programs for beef quality improvement in the Snow Dragon Beef population

Design of Zero-Differential Steering Controller for Tracked Vehicles With Hydraulic-Mechanical Transmission Based on Particle Swarm Optimization Algorithm

The handling stability of tracked vehicles not only affects the handling convenience of drivers but is also an important part of vehicle active safety. A zero-differential steering controller for tracked vehicles with hydraulic-mechanical transmissions was designed in this paper. First, the working principle of the steer-by-wire systems of tracked vehicles was analyzed, and the vehicle speed calculation model was established. Then, the steering dynamics model of the tracked vehicle was established based on the shear stress model. Finally, based on the particle swarm optimization algorithm, the established tracked vehicle steering dynamics model was iteratively solved, and the optimal yaw rate gain $K_{r}$ was calculated in real time and used for vehicle steering control. The steering control simulation model of tracked vehicles was established in MATLAB/Simulink, and the control effect of the designed steering controller was verified by the simulation. The control effect was evaluated by the comprehensive evaluation index of the handling stability. The simulation results showed that the steering controller based on the particle swarm optimization algorithm effectively improved the handling stability of the tracked vehicle and reduced the burden on the driver

Slope-Steering Motion Planning for Unmanned Tracked Vehicles Based on SSTP-RRT

Motion planning algorithms for unmanned tracked vehicles (UTV) which travel on off-road terrain often suffer from low accuracy and poor robustness when confronted with track sliding factor. SSTP-RRT (Slope-Steering Trajectory Parameter-space Rapidly-exploring Random Tree) motion planning algorithm is proposed for the slope-steering motion planning of UTV while considering the track sliding factor. A modified tracked vehicle slope-steering mechanical model is established to describe the process of UTV steering on the slope. The proposed UTV slope-steering model considers combined horizontal and vertical track sliding as well as steering centrifugal force. The PSO-LM (Particle Swarm Optimization - Levenberg Marquardt) algorithm is proposed to solve how to choose the initial values for the solution of the nonlinear system of equations of the model. The vehicle velocity, steering radii, and heading angle are taken as the independent variables, and the output rotational velocities of the inner and outer sprockets are taken as the dependent variables. The data are generated in a pre-computed way, and the output can be acquired by the point cloud surface fitting method based on moving least squares. By this method, UTV can travel according to the planned trajectory on the slope precisely and duly

Research on Characteristics of Tracked Vehicle Steering on Slope

A special design is needed for an unmanned tracked vehicle (UTV) to meet the requirements of off-road environments and complex tasks. A loose surface is the main terrain for tracked vehicles in off-road driving. Slope steering is inevitable while driving in such conditions; hence, its performance is a major concern for tracked vehicles on loose terrain. This study investigates the slope steering performance of a tracked vehicle. An improved dynamic steering model is proposed when considering the shear stress-shear displacement relation of soil at the track-ground interface. The influence of ground characteristics on the slope steering performance of a tracked vehicle is illustrated. The track slip rate is adopted as an index to evaluate the influence of typical vehicle structure parameters on the slope steering performance of a tracked vehicle. This study provides technical support for the design and optimization of UTV

An Optical Section-Assisted In Vivo Rabbit Model for Capsular Bend and Posterior Capsule Opacification Investigation.

To establish an optical section-assisted in vivo rabbit model for capsular bend and posterior capsule opacification (PCO) investigation.A total of 10 rabbits underwent phacoemulsification surgery and intraocular lens (IOL) implantation. On the basis of the relationship between the anterior capsule and IOL, the rabbits were divided into complete overlap and incomplete overlap groups, in which six and four rabbits were included, respectively. The capsular bend optical sections were assessed using ultra-long scan depth optical coherence tomography (UL-OCT), and posterior capsule opacification was evaluated with slit lamp on postoperative day 3, 7, 14, and 28. In addition, histopathological section was used to verify the accuracy of capsular bend type captured by OCT in three rabbits.Based on the special animal model, six capsular bend types were observed, namely, anterior (A), middle (M), posterior (P), detachment (D), funnel (Fun) and furcate adhesion (Fur). On day 3, capsular bend began to form. On 14 days, the capsular bends were comprised of A, M and D types, which were almost maintained until day 28. Histopathological section findings were consistent with optical sectioning results. In the incomplete and complete groups, the earliest PCO within the optical zone were on day 7 and 28, respectively. The incomplete group exhibited higher incidence and faster PCO on day 7 (p = 0.038) and 14 (p = 0.002).This animal model not only mimics capsular bend evolution and PCO processes but also produces OCT optical section images equivalent to and more repeatable than histopathology, thereby providing a promising method for the further investigations of PCO

The Effect of Anterior Capsule Polishing on Capsular Contraction and Lens Stability in Cataract Patients with High Myopia

Purpose. To evaluate the effect of anterior capsule polishing in patients with high myopia after cataract surgery. Setting. The Eye Hospital of Wenzhou Medical University, Zhejiang, China. Design. Prospective study. Methods. High myopic patients with a bilateral cataract who underwent phacoemulsification with 360° anterior capsular polishing in one eye and without polishing in the contralateral eye were recruited. The following parameters were recorded at 1, 3, and 6 months postoperatively, including the area and diameter of the anterior capsule opening (area and D), IOL tilt and decentration, refraction, and postoperative aqueous depth (PAD). Results. Paired samples of 38 eyes of 19 patients were enrolled. The area decreased significantly in both the polished group and unpolished group, whereas the diameter reduced more in the unpolished group. The IOL tilt and decentration at 3-month and 6-month follow-up showed significant differences between two groups. In the unpolished group, the IOL decentration firstly appeared between one-month to three-month visit, while the refraction error, PAD, and IOL tilt were significantly different between the three-month and six-month visits. Conclusion. 360° anterior capsule polishing can effectively reduce the extent of the anterior capsule contraction and increase the stability of IOL. The study was registered at http://www.clinicaltrials.gov, and the clinical trial accession number is NCT 03142269

Full Defects Passivation Enables 21% Efficiency Perovskite Solar Cells Operating in Air

10.1002/aenm.202001958ADVANCED ENERGY MATERIAL

Optimal design of liquid cooling structures for superfast charging cable cores under a high current load

Superchargers have become a focus of much research into new-energy vehicles, for which the cooling of high-current cable cores is a key problem that needs to be solved. To estimate influences of different core structures of liquid-cooled cables on the fluid flow and heat transfer characteristics in circular pipes, nine helical cable core structures with insertion of smooth pipes were designed taking dimethyl silicone oil as the coolant. The fluid flow and heat transfer in the pipes were studied through computational fluid dynamics (CFD) numerical simulation at different inlet velocities (0.2–2.0 m/s), and the models were verified by building an experimental platform. Numerical calculation results show that under conditions of the same Re and pitch of cable cores, the average surface temperature of three-core cables is lower than those of single-core and double-core cables. Moreover, the mean flow velocity v in pipes, heat transfer performance Nu, resistance factor f, evaluation factor for comprehensive heat transfer performance (PEC), and field synergy number Fc all increase with the decrease in the pitch of cable cores. This finding indicates that the heat transfer effect is gradually enhanced. The research implies that when the pitch p is 22.4 mm (cable C6), the velocity field is the most synergetic with the temperature field and the comprehensive heat transfer performance is optimal. This research provides an excellent cooling scheme for cable cores in superchargers under a high current load