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Simple Summary: Ashidan yak is a new breed of hornless yak developed by Chinese scientists, which has an important economic value. However, little is known about the growth of Ashidan yaks. This study analyzed the body weight and body size measurements of 260 female Ashdan yaks and compared the performance of five nonlinear models (Logistic model, Gompertz model, Brody model, von Bertalanffy model and Richards model). Our results showed that the early growth and development of Ashidan yak change with the seasons, and the Richards model performs better among the five models. Understanding animal growth plays an important role in improving animal genetics and breeding. In order to explore the early growth and development law of Ashidan yak, the body weight (BW), wither height (WH), body oblique length (BL) and chest girth (CG) of 260 female Ashidan yaks were measured. These individuals grew under grazing conditions, and growth traits were measured at 6, 12, 18 and 30 months of age. Then the absolute growth and relative growth of Ashidan yak were calculated, and five nonlinear models (Logistic model, Gompertz model, Brody model, von Bertalanffy model and Richards model) were used to fit the growth curve of Ashidan yak. The fitting effect of the model was evaluated according to MSE, AIC and BIC. The results showed that the growth rate of Ashidan yak was the fastest from 12 to 18 months old, and the growth was slow or even stagnant from 6 to 12 months old. The AIC and BIC values of the Richards model were the lowest among the five models, with an AIC value of 4543.98 and a BIC value of 4563.19. The Richards model estimated body weight at 155.642 kg. In summary, the growth rate of female Ashidan yak changes with the seasons, growing faster in warm seasons and slower in cold seasons. Richards model is the best model to describe the growth curve of female Ashidan yak in five nonlinear models. [ABSTRACT FROM AUTHOR]

Long-haired individuals in the Tianzhu white yak population are a unique genetic resource, and have important landscape value. Copy number variation (CNV) is an important source of phenotypic variation in mammals. In this study, we used resequencing technology to detect the whole genome of 10 long-haired Tianzhu white yaks (LTWY) and 10 normal-haired Tianzhu white yaks (NTWY), and analyzed the differences of CNV in the genome of LTWYs and NTWYs. A total of 110268 CNVs were identified, 2006 CNVRs were defined, and the distribution map of these CNVRs on chromosomes was constructed. The comparison of LTWYs and NTWYs identified 80 differential CNVR-harbored genes, which were enriched in lipid metabolism, cell migration and other functions. Notably, some differential genes were identified as associated with hair growth and hair-follicle development (e.g., ASTN2, ATM, COL22A1, GK5, SLIT3, PM20D1, and SGCZ). In general, we present the first genome-wide analysis of CNV in LTWYs and NTWYs. Our results can provide new insights into the phenotypic variation of different hair lengths in Tianzhu white yaks. [ABSTRACT FROM AUTHOR]

Cattle-yak is a hybrid F1 generation of cattle and yak, which has a history of more than 3000 years and has shown better production performance and higher economic benefits than those of yaks. However, up to now, there has been no study on the transcriptome-wide m6A methylation profile of bovine skeletal muscle and its potential biological function during muscle development. Here, we observed significant changes in the expression levels of muscle-related marker genes and methylation-related enzymes during the development of cattle-yak, and the overall m6A content in the Longissimus dorsi muscle of 18-month-old cattle-yak decreased significantly. A total of 36,602 peaks, 11,223 genes and 8388 lncRNAs were identified in the two groups, including 2989 differential peaks (427 up-regulated peaks and 2562 down-regulated peaks), 1457 differentially expressed genes (833 up-regulated genes and 624 down-regulated genes) and 857 differentially expressed lncRNAs (293 up-regulated lncRNAs and 564 down-regulated lncRNAs). GO and KEGG analysis revealed that they were significantly enriched in some muscle-related pathways (Wnt signaling pathway and MAPK signaling pathway) and high-altitude adaptation-related pathway (HIF-1 signaling pathway). Moreover, m6A abundance was positively correlated with gene expression levels, while it was negatively correlated with lncRNA expression levels. This indicates that m6A modification played an important role in the Longissimus dorsi muscle development of cattle-yak; however, the regulation mechanism of m6A-modified mRNA and lncRNA may be different. This study was the first report of transcriptome-wide m6A-modified mRNAs and lncRNAs atlas in the Longissimus dorsi muscle development of cattle-yak, one which will provide new perspectives for genetic improvement in bovines. [ABSTRACT FROM AUTHOR]

A new driving robot shifting manipulator for vehicle exhaust emission test is designed for the special motion trajectory of the car shifting joystick. The gear shifting operation is completed by adopting the planar five-bar linkage mechanism as the transmission mechanism of the manipulator plus the new end effector. Due to the small working space of the gear shifting manipulator, the penalty function method is applied to optimize the size of the mechanism Considering the assembly condition of the linkage mechanism, the dynamics of the mechanism and the constraint of the working space, the minimal sum of the lengths of the connecting rods is set to the objective function to obtain the optimal solution. The prototype model is built in SolidWorks software, the mechanism kinematics simulation is conducted by Simulink, and the mechanical analysis is performed by ANSYS Workbench, which provides an efficient simulation method for the optimization design of the mechanism The simulation results show that the shifting manipulator can respond within 0.1s during the gear selection and the gear shifting action, and the action can be completed at the specified time and speed to meet the national standard requirements for car shifting. The parameters of the shifting manipulator and the rationality of the model are verified by mechanical simulation. The results show that the shifting manipulator can achieve the selection and the shifting action, and the movement is smooth, indicating a good practical application value. [ABSTRACT FROM AUTHOR]

To improve the vehicle ride comfort, a variable cross track vehicle magnetorheological (MR) suspension system was designed for high clearance, track stepless and adjustable field work And a time domain excitation model for land unevenness of ridge and furrow was constructed by using trigonometric series method. To optimize the nonlinear dynamic characteristics of the suspension system and enhance the response speed of MR damper, equation of state of the suspension system was established by adopting land unevenness of ridge and furrow as random excitation source of system, wheel and body vertical displacement as inputs, optimization parameters of the suspension system as state variables, and damper real-time control current as output. And the fuzzy PID control model of the system was built based on MATLAB/Simulink module. The results show that after fuzzy PID control on the MR suspension system, the maximum vertical displacement of the body and the wheel are respectively 0.093 43 m and 0.015 2 m, and the degree of dispersion is decreased by 55% and 99.5%, much lower than that before control. The ride comfort of the variable cross track vehicle is improved significantly and the control current is well consistent with the damping force, which reduces the hysteretic response. [ABSTRACT FROM AUTHOR]

A dense $${\text{BaCe}}_{{\text{0}}{\text{.8}}} {\text{Sm}}_{{\text{0}}{\text{.2}}} {\text{O}}_{{\text{3 - }}\delta } $$ (BCSO) membrane was fabricated by a modified suspension spraying on porous NiO–BCSO anode support. In the process, the suspension was directly prepared by ball-milling the BaCO3, CeO2, and Sm2O3 powders in ethanol. A dense and uniform electrolyte layer in the thickness of 10 μm was successfully prepared on porous anode support by suspension spray process after co-sintering at 1,400 °C for 5 h. With $${\text{Nd}}_{{\text{0}}{\text{.7}}} {\text{Sr}}_{{\text{0}}{\text{.3}}} {\text{MnO}}_{{\text{3 - }}\sigma } $$ (NSMO) cathode, a single cell was assembled and tested with hydrogen and ammonia as fuels, respectively. The hydrogen-fueled cell exhibits 1.01 V for open circuit voltage (OCV) and 560 mW/cm2 for peak power density at 700 °C. In comparison, the cell in ammonia displays a similar performance (1.02 V for OCV and 530 mW/cm2 for output), which indicates the liquid ammonia is a promising substitute for hydrogen. Moreover, the fuel cell displays good interface contacts. To sum up, ammonia-fueled solid oxide fuel cells prepared by this simple suspension spray is an alternative way to promote the commercialization. [ABSTRACT FROM AUTHOR]

Porous cordierite ceramics were prepared from a mixture of coal fly ash and basic magnesium carbonate at 1100–1350°C. Porosity, flexural strength and thermal expansion coefficient of the samples sintered at 1300°C were estimated to be 26%, 65 MPa and 4.21×10−6/°C, respectively. The kinetics of the formation progress was investigated by stepwise isothermal dilatometry (SID) accompanied with XRD, SEM and porosity measurement. It was found that the isothermal shrinkage data from SID could be well analyzed to get kinetic parameters according to the empirical rate equation developed by Makipirtti-Meng, dY/dt = nk( T) Y(1 − Y)( Y/1 − Y) n/1, where Y is the fractional shrinkage during the sintering process and n is a dimensionless component. The apparent activation energy Δ E values for 900–1000°C and 1050–1150°C were 1294 and 1778 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

A thin Ba3Ca1.18Nb1.82O9−δ (BCN18) membrane electrolyte was prepared by a novel and facile method on a NiO–BCN18 anode substrate. The interesting aspect of the method was the adoption of a in situ reaction of BaCO3, CaCO3, and Nb2O5 on the anode substrate to prepare a dense BCN18 membrane. The BCN18 membrane obtained, which was about 15 μm in thickness and showed high chemical stability against H2O and CO2, attained a high density after sintering at 1400°C. The elemental composition of the BCN18 membrane prepared was identified by energy-dispersive X-ray spectroscopy analysis. With La0.7Sr0.3FeO3−σ (LSF) as the cathode, the fuel cell performance with the structure of Ni–BCN18/BCN18/LSF was studied. [ABSTRACT FROM AUTHOR]

Yttria-stabilized zirconia (YSZ) thin films were prepared by conventional and modified dip-coating techniques followed by heating to an appropriate temperature in air. Scanning electron microscopy showed that films of the thickness ranging from 20 to 30 μm were dense and crack-free. The electrical properties of the films were investigated by ac impedance spectroscopy. La0.8Sr0.2MnO3 paste was printed on to a YSZ electrolyte/anode assembly to create single fuel cells which were tested in the temperature range 650–800 °C. The results showed that both open circuit voltage (OCV) and maximum power density values of the cells with electrolytes produced by the modified dip coating were higher than those fabricated by conventional processing. At 800 °C, the OCV reached 0.98 V and a maximum power density of 190 mW cm-2 was attained, demonstrating that the modified dip coating process is a simple and cost-effective fabrication technique for IT-SOFCs, though further improvement is necessary. [ABSTRACT FROM AUTHOR]

Fine $$ SrTiO_3 $$ and Sr(Mg0.4Ti0.6)O3–δ powders were prepared by a sol-precipitation method. Tetraisopropyl titanate was used as a starting material, which firstly chelated with the acetic acid to form a water-soluble titanyl precursor. This precursor was then precipitated in a strong NaOH solution, to which, a nitrate solution of the required ratio of $$ Mg^{2 + } /Sr^{2 + } $$ was also added. By properly controlling reaction conditions, high crystalline undoped and Mg-doped strontium titanates with the dominating perovskite structures could be obtained directly at 80 °C. Owing to the chelating reaction of tetraisopropyl titanate with the acetic acid, the problem of the premature hydrolysis of titanium precursor was circumvented. The rates of the hydrolysis and condensation of titanyl acylate were also diminished. The final powder obtained had a uniform particle size of 40–60 nm. The formation mechanisms of $$ SrTiO_3 $$ and Sr(Mg0.4Ti0.6)O3–δ were also discussed. This study indicated that in the entire sol-precipitation process, the mixing of cations was homogeneous and the diffusion of alkaline earth cations into titanium particles occurred all at atomic level, which allowed the realization of the optimized solid-solubility in the complex oxide system. This method could be exploited for the preparation of other doped titanates. [ABSTRACT FROM AUTHOR]

Perovskite La0.6Sr0.4Co0.8Fe0.2O3−δ (LSCF) powders have been successfully synthesized from oxide and carbonates based on the principle of gelcasting. Phase-forming temperature is very dependent on the ball-milling process during the suspension preparation. As the ball-milling time is increased, the temperature of phase formation decreases, therefore the perovskite powder obtained has a larger Brunaver–Emmett–Teller (BET) specific surface area. The grain sizes were around 1 μm at 1000°C and 2 μm at 1100°C from scanning electron microscopy (SEM) photographs. The perovskite powders have good sinterability: the sintering densities of ceramic bodies shaped with as-prepared powders were investigated. SEM photos show that sintered ceramics exhibit a well defined morphology in the packing and sintering of particles. The oxygen permeance of disc shaped samples, with a thickness ranging from 1.02 to 1.98 mm was 6.39 × 10−8–1.99 × 10−8 mol cm−2 s−1 at 900°C indicating that LSCF ceramics have high oxygen permeation. It can be concluded that gelcasting is a simple and effective method for preparing practical multicomponent perovskite powders. [ABSTRACT FROM AUTHOR]