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Effect of Saccharomyces cerevisiae on alfalfa nutrient degradation characteristics and rumen microbial populations of steers fed diets with different concentrate-to-forage ratios 被引量:16
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作者 Gengzhi Ding Ying Chang +3 位作者 Liping Zhao Zhenming Zhou Liping Ren Qingxiang Meng 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第4期430-438,共9页
Live yeast(Saccharomyces cerevisiae) constitutes an effective additive for animal production;its probiotic effect may be related to the concentrate-to-forage ratio(CTFR).The objective of this study was to assess t... Live yeast(Saccharomyces cerevisiae) constitutes an effective additive for animal production;its probiotic effect may be related to the concentrate-to-forage ratio(CTFR).The objective of this study was to assess the effects of S.cerevisiae(SC) on fiber degradation and rumen microbial populations in steers fed diets with different levels of dietary concentrate.Ten Simmental × Local crossbred steers(450 ± 50 kg BW) were assigned to a control group or an SC group.Both groups were fed the same basal diet but the SC group received SC supplementation(8 × 10^9 cfu/h/d through the ruminal fistula)following a two-period crossover design.Each period consisted of four phases,each of which lasted 17 d:10 d for dietary adaptation,6 d for degradation study,and 1 d for rumen sample collection.From the 1^(st) to the 4^(th) phase,steers were fed in a stepwise fashion with increasing CTFRs,i.e.,30:70,50:50,70:30,and 90:10.The kinetics of dry matter and fiber degradation of alfalfa pellets were evaluated;the rumen microbial populations were detected using real-time PCR.The results revealed no significant(P〉 0.05) interactions between dietary CTFR and SC for most parameters.Dietary CTFR had a significant effect(P〈 0.01) on degradation characteristics of alfalfa pellets and the copies of rumen microorganism;the increasing concentrate level resulted in linear,quadratic or cubic variation trend for these parameters.SC supplementation significantly(P〈 0.05) affected dry matter(DM) and neutral detergent fiber(NDF)degradation rates(c_(DM),c_(NDF)) and NDF effective degradability(ED_(NDF)).Compared with the control group,there was an increasing trend of rumen fungi and protozoa in SC group(P 〈 0.1);copies of total bacteria in SC group were significantly higher(P〈 0.05).Additionally,percentage of Ruminobacter amylophilus was significantly lower(P〈 0.05)but percentage of Selenomonas ruminantium was significantly higher(P〈 0.05) in the SC group.In a word,dietary CTFR had a significant effect on degradation characteristics of forage and rumen microbial population.S.cerevisiae had positive effects on DM and NDF degradation rate or effective degradability of forage;S.cerevisiae increased rumen total bacteria,fungi,protozoa,and lactate-utilizing bacteria but reduced starch-degrading and lactate-producing bacteria. 展开更多
关键词 Concentrate-to-forage ratios In situ Real-time PCR Rumen microorganism steers
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Subcutaneous fatty acid composition of steers finished as weanlings or yearlings with and without growth promotants
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作者 Cletos Mapiye Tyler D Turner +3 位作者 John A Basarab Vern S Baron Jennifer L Aalhus Michael ER Dugan 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第1期98-105,共8页
Background: The current study evaluated the subcutaneous fatty acid (FA) composition of calf- and yearling-fed steer with or without growth promoting implants. Crossbred steers (n = 112; 267 ± 5.0 kg) of the... Background: The current study evaluated the subcutaneous fatty acid (FA) composition of calf- and yearling-fed steer with or without growth promoting implants. Crossbred steers (n = 112; 267 ± 5.0 kg) of the same contemporary group were allocated to one of four production system and implant strategy based treatments in a completely randomized design with a 2 × 2 factorial arrangement of treatments. Results: There were no interactions (P 〉 0.05) between production systems and growth promoting implants for the total and individual subcutaneous FA. Yearling as opposed to calf finishing reduced (P 〈 0.05) subcutaneous proportions of C20:3n-6, trans (t)l 2-18:1, C14:0, several minor cis-monounsaturated FA (c-MUFA; c9-14:1, c11-16:1, cl 1-18:1, cl 2-18:1, cl 3-18:1, c9-20:1 and cl 1-20:1), and increased (P 〈 0.05) subcutaneous proportions of tl 1 cl 5-18:2, total and individual branched-chain FA. Subcutaneous fat from steers implanted with growth promotants had higher (P 〈 0.05) proportions of total polyunsaturated FA (PUFA), total n-6 PUFA, C18:2n-6 and individual t-18:1 isomers (t6 to tl0) compared to non-implanted steers. Conclusions: Overall, current findings show that production systems and growth promotants led to only minor differences in subcutaneous FA composition of beef steers. 展开更多
关键词 Age at feedlot entry BEEF Fatty acids Growth implant steers
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Effects of Plant Tannin Extracts Supplementation on Animal Performance and Gastrointestinal Parasites Infestation in Steers Grazing Winter Wheat 被引量:1
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作者 B. R. Min K. Hernandez +3 位作者 W. E. Pinchak R. C. Anderson J. E. Miller E. Valencia 《Open Journal of Animal Sciences》 2015年第3期343-350,共8页
Twenty-six stocker cattle (286.1 ± 25.7 kg) were used to quantify the effect of commercial plant tannin extracts (control vs. mimosa and chestnut tannins) on animal performance, gastrointestinal parasites control... Twenty-six stocker cattle (286.1 ± 25.7 kg) were used to quantify the effect of commercial plant tannin extracts (control vs. mimosa and chestnut tannins) on animal performance, gastrointestinal parasites control and plasma metabolite changes in heifers grazing winter wheat forage (Triticum aestivum L. var. “cutter”). The forage biomass and crude protein content were generally similar among treatments. Initial live-weight (LW) was similar among treatments, although final LW (P = 0.1) and average daily gain (ADG;P P Ostertagia was lower (P P P < 0.02) for chestnut tannins group than for control, and intermediate for mimosa tannins. However, cholesterol level was similar among treatment after 20 days cessation of tannins treatments. Our data suggest that heifers grazing winter wheat forage supplemented with plant tannins rather than control (non-tannins group) increased ADG (8% to 19%) for mimosa and chestnut tannins groups, respectively with no detectable detrimental effects on animal health. The increase in ADG may be due to decrease fecal parasites infections. 展开更多
关键词 Average Daily Gain Gastrointestinal Parasites STEER TANNINS
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Effects of a blend of Saccharomyces cerevisiae-based direct-fed microbial and fermentation products on plasma carbonylmetabolome and fecal bacterial community of beef steers
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作者 James A.Adeyemi Sunday O.Peters +2 位作者 Marcos De Donato Andres Pech Cervantes Ibukun M.Ogunade 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第2期504-513,共10页
Background:Previous studies have evaluated the metabolic status of animals fed direct-fed microbial(DFM)using enzyme-based assays which are time-consuming and limited to a few metabolites.In addition,little emphasis h... Background:Previous studies have evaluated the metabolic status of animals fed direct-fed microbial(DFM)using enzyme-based assays which are time-consuming and limited to a few metabolites.In addition,little emphasis has been placed on investigating the effects of DFM on hindgut microbiota.We examined the effects of dietary supplementation of a blend of Saccharomyces cerevisiae-based DFM and fermentation products on the plasma concentrations of carbonyl-containing metabolites via a metabolomics approach,and fecal bacterial community,via 16S rRNA gene sequencing,of beef steers during a 42-day receiving period.Forty newly weaned steers were randomly assigned to receive a basal diet with no additive(CON;n=20)or a basal diet supplemented with 19 g of Commence™(PROB;n=20)for a 42-day period.Commence™(PMI,Arden Hills,MN)is a blend of 6.2×1011 cfu/g of S.cerevisiae,3.5×1010 cfu/g of a mixture of Enterococcus lactis,Bacillus subtilis,Enterococcus faecium,and Lactobacillus casei,and the fermentation products of these aforementioned microorganisms and those of Aspergillus oryzae and Aspergillus niger.On d 0 and 40,rectal fecal samples were collected randomly from 10 steers from each treatment group.On d 42,blood was collected for plasma preparation.Results:A total number of 812 plasma metabolites were detected.Up to 305 metabolites[fold change(FC)≥1.5,FDR≤0.01]including glucose,hippuric acid,and 5-hydroxykynurenamine were increased by PROB supplementation,whereas 199 metabolites(FC≤0.63,FDR≤0.01)including acetoacetate were reduced.Supplementation of PROB increased(P≤0.05)the relative abundance of Prevotellaceae UCG-003,Megasphaera,Dorea,Acetitomaculum,and Blautia.In contrast,the relative abundance of Elusimicrobium,Moheibacter,Stenotrophomonas,Comamonas,and uncultured bacterium belonging to family p-2534-18B5 gut group(phylum Bacteroidetes)were reduced(P≤0.05).Conclusions:The results of this study demonstrated that supplementation of PROB altered both the plasma carbonyl metabolome towards increased glucose concentration suggesting an improved energy status,and fecal bacterial community,suggesting an increased hindgut fermentation of the beef steers. 展开更多
关键词 Beef steer CARBONYL Fecal bacteria Lactate-utilizing bacteria Plasma metabolomics
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Comparison of the effects of taurine and methionine supplementation on the nitrogen metabolism of beef steers elucidated through plasma metabolome profiling
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作者 Yufeng Liu Cheng Liu +3 位作者 Shuo Zhang Jinming Hu Meng M.Li Guangyong Zhao 《Animal Nutrition》 2025年第1期376-386,共11页
The objectives of the experiment were to compare the effects of rumen-protected taurine (RPT) and rumen-protected methionine (RPM) on the nitrogen (N) metabolism,plasma biochemical parameters,and metabolomics in beef ... The objectives of the experiment were to compare the effects of rumen-protected taurine (RPT) and rumen-protected methionine (RPM) on the nitrogen (N) metabolism,plasma biochemical parameters,and metabolomics in beef steers and to clarify whether taurine plays similar roles as methionine (Met) in the regulation of N metabolism in beef steers.Six Simmental steers aged 12 months (liveweight325±7 kg) were used as experimental animals.The experimental treatments included a basal diet,the basal diet+70.0 g/d RPT and the basal diet+74.2 g/d RPM.The treatments were assigned in a replicated3×3 Latin square design.Each experimental period included 15 d for adaptation and 5 d for sampling.The results showed that supplementing the diet with RPT or RPM did not affect the apparent nutrient digestibility (P>0.05).Supplementing the diet with RPT or RPM increased the N retention (P<0.05) and the N utilization efficiency (NUE)(P<0.05) and decreased the urinary excretion of 3-methylhistidine(P<0.05) and the estimated skeletal protein degradation rate (P<0.05).Supplementing the diet with RPT increased the plasma concentrations of taurine (P<0.001),cysteine (P=0.010),valine (P=0.013)and total non-essential amino acids (NEAA)(P=0.047) and tended to increase the plasma concentrations of essential amino acids (EAA)+NEAA (P=0.087),but it did not affect the plasma concentrations of total EAA (P>0.05).Supplementing the diet with RPM increased the plasma concentrations of methionine(P=0.033),lysine (P=0.047),cysteine (P=0.007),leucine (P=0.046),isoleucine (P=0.046),valine(P=0.034),total EAA (P=0.028),total NEAA (P=0.004) and EAA+NEAA (P=0.004).The plasma metabolomics profiling revealed that supplementing the diet with RPT upregulated the plasma concentrations of taurine (P<0.001),L-cysteine (P=0.004) and some amino acid (AA) analogues (P<0.05)and RPM upregulated the plasma concentrations of Met (P=0.021),L-isoleucine (P=0.036),L-tryptophan (P=0.006) and some AA analogues (P<0.05).In conclusion,taurine has similar impacts to Met in improving the N retention and the NUE in beef steers.Taurine deficiency negatively affects the NUE of beef steers.Supplementation of the diet with taurine is beneficial to the N utilization in beef steers. 展开更多
关键词 METHIONINE Nitrogen metabolism STEER TAURINE
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PID Steering Control Method of Agricultural Robot Based on Fusion of Particle Swarm Optimization and Genetic Algorithm
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作者 ZHAO Longlian ZHANG Jiachuang +2 位作者 LI Mei DONG Zhicheng LI Junhui 《农业机械学报》 北大核心 2026年第1期358-367,共10页
Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion... Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion algorithm took advantage of the fast optimization ability of PSO to optimize the population screening link of GA.The Simulink simulation results showed that the convergence of the fitness function of the fusion algorithm was accelerated,the system response adjustment time was reduced,and the overshoot was almost zero.Then the algorithm was applied to the steering test of agricultural robot in various scenes.After modeling the steering system of agricultural robot,the steering test results in the unloaded suspended state showed that the PID control based on fusion algorithm reduced the rise time,response adjustment time and overshoot of the system,and improved the response speed and stability of the system,compared with the artificial trial and error PID control and the PID control based on GA.The actual road steering test results showed that the PID control response rise time based on the fusion algorithm was the shortest,about 4.43 s.When the target pulse number was set to 100,the actual mean value in the steady-state regulation stage was about 102.9,which was the closest to the target value among the three control methods,and the overshoot was reduced at the same time.The steering test results under various scene states showed that the PID control based on the proposed fusion algorithm had good anti-interference ability,it can adapt to the changes of environment and load and improve the performance of the control system.It was effective in the steering control of agricultural robot.This method can provide a reference for the precise steering control of other robots. 展开更多
关键词 agricultural robot steering PID control particle swarm optimization algorithm genetic algorithm
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Quantum steering for two-mode states with continuous-variable in laser channel
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作者 Kaimin Zheng Jifeng Sun +1 位作者 Liyun Hu Lijian Zhang 《Chinese Physics B》 2026年第2期329-341,共13页
Einstein–Podolsky–Rosen(EPR)steering is an important resource for one-sided device-independent quantum information processing.This steering property can be destroyed by the interaction between a quantum system and i... Einstein–Podolsky–Rosen(EPR)steering is an important resource for one-sided device-independent quantum information processing.This steering property can be destroyed by the interaction between a quantum system and its environment in practical applications.In this paper,we employ the characteristic function representation of probability distributions to investigate the quantum steering of two-mode continuous-variable states in a laser channel,where both the gain factor and the loss effect are taken into account.Firstly,we analyse the steering time of the two-mode squeezed vacuum state under one-mode and two-mode laser channels,respectively.We find that the gain process introduces additional noise into the two-mode squeezed vacuum state,thereby reducing the steerable time.Secondly,by quantifying EPR steering,we show that two-side loss exhibits smaller steerability than one-side loss,although they share the same two-way steerable time.In addition,we find that the more-gained party can steer the other party’s state,whereas the other party cannot steer the gained party beyond a certain threshold value.In this sense,the gain effect in one party appears to be equivalent to the loss effect in the other party.Our results pave the way for the distillation of EPR steering and quantum information processing in practical quantum channels. 展开更多
关键词 Einstein-Podolsky-Rosen steering laser channel characteristic function
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Steering China’s High-Quality Growth
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作者 《China Today》 2026年第1期16-19,共4页
Chinese President Xi Jinping has guided China through a year of resilient growth via forward-looking reforms and innovation-driven transformation that is shaping the nation’s economic trajectory for 2026 and beyond.
关键词 forward looking reforms high quality growth STEERING resilient growth innovation driven transformation
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Metabolomic and transcriptomic study to understand changes in metabolic and immune responses in steers under heat stress 被引量:2
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作者 Jun Sik Eom Da Som Park +7 位作者 Sang Jin Lee Bon-Hee Gu Shin Ja Lee Sang-Suk Lee Seon-Ho Kim Byeong-Woo Kim Sung Sill Lee Myunghoo Kim 《Animal Nutrition》 SCIE CSCD 2022年第4期87-101,共15页
Heat stress(HS)damages livestock by adversely affecting physiological and immunological functions.However,fundamental understanding of the metabolic and immunological mechanisms in animals under HS remains elusive,par... Heat stress(HS)damages livestock by adversely affecting physiological and immunological functions.However,fundamental understanding of the metabolic and immunological mechanisms in animals under HS remains elusive,particularly in steers.To understand the changes on metabolic and immune responses in steers under HS condition,we performed RNA-sequencing and proton nuclear magnetic resonance spectroscopy-based metabolomics on HS-free(temperature humidity index[THI]value:64.92±0.56)and HS-exposed(THI value:79.13±0.56)Jersey steer(n=8,body weight:559.67±32.72 kg).This study clarifies the metabolic changes in 3 biofluids(rumen fluid,serum,and urine)and the immune responses observed in the peripheral blood mononuclear cells of HS-exposed steers.This integrated approach allowed the discovery of HS-sensitive metabolic and immunological pathways.The metabolomic analysis indicated that HS-exposed steers showed potential HS biomarkers such as isocitrate,formate,creatine,and riboflavin(P<0.05).Among them,there were several integrative metabolic pathways between rumen fluid and serum.Furthermore,HS altered mRNA expression and immune-related signaling pathways.A meta-analysis revealed that HS decreased riboflavin metabolism and the expression of glyoxylate and dicarboxylate metabolism-related genes.Moreover,metabolic pathways,such as the hypoxia-inducible factor-1 signaling pathway,were downregulated in immune cells by HS(P<0.05).These findings,along with the datasets of pathways and phenotypic differences as potential biomarkers in steers,can support more in-depth research to elucidate the interrelated metabolic and immunological pathways.This would help suggest new strategies to ameliorate the effects of HS,including disease susceptibility and metabolic disorders,in Jersey steers. 展开更多
关键词 Heat stress Jersey steer METABOLOME Transcriptome Immunity Metabolism
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Improving Path Tracking Performance of 4WIS Vehicles via Constraint-Oriented Consistent Coordinated Steering
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作者 Zeyu Yang Yusheng Dai +3 位作者 Manjiang Hu Yougang Bian Qingjia Cui Yang Li 《Chinese Journal of Mechanical Engineering》 2025年第5期176-190,共15页
Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4... Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4WIS)vehicles,the steering systems of the four wheels are relatively independent,and there are differences and uncertainties in individual steering dynamics,which lead to challenges for all four wheels in simultaneously satisfying the ASP and may deteriorate the vehicle path tracking performance.In response to this problem,this paper introduces a four-wheel consistent coordinated steering control for 4WIS vehicles.The algorithm innovatively reconfigures the Ackerman steering relationships as coupling constraints among the wheels,and utilizes the constraint-following method to design controller.The controller achieves uniform boundedness(UB)and uniform ultimate boundedness(UUB)of ASP constraint error.The Carsim/Simulink joint simulation results demonstrate that the algorithm guarantees the approximate satisfaction of ASP in both the transient and steady-state of the vehicle path tracking.Also,it significantly improves the path tracking performance. 展开更多
关键词 Four-wheel independent steering Path tracking Constraint-following control Consistent coordinated control Ackerman steering principle UNCERTAINTIES
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Distributed Finite-Time Event-Triggered Formation Control Based on a Unified Framework of Affine Image
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作者 Yan-Jun Lin Yun-Shi Yang +1 位作者 Li Chai Zhi-Yun Lin 《IEEE/CAA Journal of Automatica Sinica》 2025年第6期1289-1291,共3页
Dear Editor,This letter concentrates on distributed event-triggered formation control problems with finite-time convergence in an arbitrarily dimensional Euclidean space.A new unified approach of finite-time event-tri... Dear Editor,This letter concentrates on distributed event-triggered formation control problems with finite-time convergence in an arbitrarily dimensional Euclidean space.A new unified approach of finite-time event-triggered formation control is proposed by steering all agents to a sliding manifold(the affine image)to achieve general formations,like affine,rigid or translational formation.It only requires to design an extra steering law driving at least d+1 leaders from an affine image to a rigid or translational image,where d is the dimension of the space.The event-triggered function is designed in a distributed and discontinuous manner based only on local information to reduce the communication and calculation resources by aperiodic sampling.In the proposed event-triggered formation law,zeno-free behavior is ensured. 展开更多
关键词 event triggered control distributed control affine image steering all agents finite time convergence general formationslike sliding manifold steering law
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Investigating maximal steered coherence under the common impacts of reservoir and noise
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作者 Ling-Ling Xing Huan Yang Gang Zhang 《Chinese Physics B》 2025年第5期230-235,共6页
Maximal steered coherence(MSC)is a noteworthy resource measure in the field of quantum information,and it is defined under the framework of coherence measure and the formalism of quantum steering ellipsoids(QSEs).Here... Maximal steered coherence(MSC)is a noteworthy resource measure in the field of quantum information,and it is defined under the framework of coherence measure and the formalism of quantum steering ellipsoids(QSEs).Here,we explore the MSC of a two-qubit X state under the common influences of reservoir and noise.The results disclose that the introduction of auxiliary qubits can give rise to enhancement of the MSC in both the strong and weak coupling regimes.Moreover,more auxiliary qubits can decrease the oscillation period of the MSC,and also suppress the oscillation amplitude of the MSC in the strong coupling regime.In contrast,the increases in auxiliary qubits result in the oscillation of the MSC for the setting of the initially weak coupling regime.Of particular interest is that the improvement effects of more auxiliary qubits on the MSC in the initially weak coupling regime are significantly stronger than that in the initially strong coupling regime. 展开更多
关键词 maximal steered coherence quantum steering ellipsoid RESERVOIR noise
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STEERING APEC TOWARD SHARED GROWTH President Xi Jinping’s APEC trip underscores China’s resolve to advance openness,cooperation,and shared prosperity across the Asia-Pacific region
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《China Report ASEAN》 2025年第12期36-37,共2页
From October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to t... From October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to the country.This was Xi Jinping’s first overseas trip following the conclusion of the fourth plenary session of the 20th Communist Party of China Central Committee,underscoring its importance on China’s diplomatic agenda. 展开更多
关键词 APEC china RESOLVE OPENNESS STEERING xi jinping shared growth PRESIDENT
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Dynamic terahertz multi-channel beam steering with dual-frequency multiplexing based on magneto-optical metasurfaces
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作者 Dan Zhao Fei Fan +5 位作者 Hao Wang Pengxuan Li Zhen Xu Jining Li Yunyun Ji Shengjiang Chang 《Advanced Photonics Nexus》 2025年第3期149-157,共9页
With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A mag... With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication. 展开更多
关键词 TERAHERTZ MULTI-CHANNEL DUAL-FREQUENCY nonreciprocal transmission beam steering dynamics
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Steering APEC Toward Shared Growth
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作者 《China Today》 2025年第12期16-19,共4页
President Xi Jinping’s APEC trip underscores China’s resolve to advance openness,cooperation,and shared prosperity across the Asia-Pacific region.FROM October 30 to November 1,2025,Chinese President Xi Jinping trave... President Xi Jinping’s APEC trip underscores China’s resolve to advance openness,cooperation,and shared prosperity across the Asia-Pacific region.FROM October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to the country. 展开更多
关键词 APEC China state visit OPENNESS STEERING xi jinping shared growth president
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Analysis of Coordinated Steering Performance in Multi-wheel Landing Gears
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作者 GUI Xiwen ZHANG Ming +2 位作者 SHI Xiazheng HU Tianyang XU Yuhan 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期659-678,共20页
During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To ad... During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To address this issue,the rear landing gear is typically designed to steer in coordination with the nose wheels,reducing sideslip and improving maneuverability.This study examines how structural parameters and weight distribution affect the performance of coordinated steering in landing gear design for large transport aircraft.Using the C-5 transport aircraft as a case study,we develop a multi-wheel ground steering dynamics model,incorporating the main landing gear(MLG)deflection.A ground handling dynamics model is also established to evaluate the benefits of coordinated steering for rear MLG during steering.Additionally,the study analyzes the impact of structural parameters such as stiffness and damping on the steering performance of the C-5.It further investigates the effects of weight distribution,including the center-of-gravity(CG)height,the longitudinal CG position,and the mass asymmetry.Results show that when the C-5 employs coordinated steering for rear MLG,the lateral friction coefficients of the NLG tires decrease by 22%,24%,26%,and 27%.The steering radius is reduced by 29.7%,and the NLG steering moment decreases by 19%,significantly enhancing maneuverability.Therefore,in the design of landing gear for large transport aircraft,coordinated MLG steering,along with optimal structural and CG position parameters,should be primary design objectives.These results provide theoretical guidance for the design of multi-wheel landing gear systems in large transport aircraft. 展开更多
关键词 multi-wheel landing gear coordinated steering aircraft ground steering dynamics influence law analysis
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Far-field calibration of automotive millimeter wave radar via near-field implementation
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作者 SUN Jinghu LIU Jiahuan +3 位作者 WEI Wenqiang YU Xianxiang CUI Guolong ZHANG Xiuyin 《Journal of Systems Engineering and Electronics》 2025年第3期694-700,共7页
To enhance direction of arrival(DOA)estimation accuracy,this paper proposes a low-cost method for calibrating farfield steering vectors of large aperture millimeter wave radar(mmWR).To this end,we first derive the ste... To enhance direction of arrival(DOA)estimation accuracy,this paper proposes a low-cost method for calibrating farfield steering vectors of large aperture millimeter wave radar(mmWR).To this end,we first derive the steering vectors with amplitude and phase errors,assuming that mmWR works in the time-sharing mode.Then,approximate relationship between the near-field calibration steering vector and the far-field calibration steering vector is analyzed,which is used to accomplish the mapping between the two of them.Finally,simulation results verify that the proposed method can effectively improve the angle measurement accuracy of mmWR with existing amplitude and phase errors. 展开更多
关键词 automotive millimeter wave radar far-field steering vector calibration near-field steering vector calibration direction of arrival(DOA)estimation low cost
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Optimization Design and Numerical Evaluation of Waterjet Steering and Reversing Gear
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作者 GONG Jie WU Zhong-wan +2 位作者 SUN Yi-dan DING Jiang-ming SU Jun-jun 《China Ocean Engineering》 2025年第2期268-279,共12页
This study aims to enhance the maneuvering advantages of the waterjet unit through parametric design,performance evaluation,and optimization of the one-piece waterjet propulsion steering and reversing gear(SRG).The SR... This study aims to enhance the maneuvering advantages of the waterjet unit through parametric design,performance evaluation,and optimization of the one-piece waterjet propulsion steering and reversing gear(SRG).The SRG’s performance evaluation stems mainly from the effect of the free surface,the varying sailing speeds of the ship,and its performance while functioning at the stern of the waterjet-propelled vessel.Parameters such as the length,width,and height of the steering gear,as well as the inclination,width,and curvature of the reversing gear,significantly influence the SRG.Although the free surface has a great impact on the force of the SRG,its performance trend remains unaffected.When the SRG operates at the stern of the ship,the optimized scheme’s lateral force improves by an average of 8.08%for sailing with a rudder angle condition and an average of 45.69%for reversing sailing with a rudder angle condition.The longitudinal force of the optimized scheme improves by more than 23%when sailing without a rudder angle condition and by an average of 31.75%when sailing with a reversed rudder angle condition.Additionally,the speed of the rotor has a minimal effect on the lateral force and a significant effect on the longitudinal force. 展开更多
关键词 waterjet steering and reversing gear HYDRODYNAMICS OPTIMIZATION
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Multipartite entanglement and one-way steering in magnon frequency comb
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作者 Qianjun Zheng Yunshan Cao Peng Yan 《Chinese Physics B》 2025年第10期124-132,共9页
We theoretically demonstrate that multipartite entanglement and one-way Einstein-Podolsky-Rosen(EPR)steering in a magnon frequency comb(MFC)can be generated in a hybrid magnon-skyrmion system.When the system is driven... We theoretically demonstrate that multipartite entanglement and one-way Einstein-Podolsky-Rosen(EPR)steering in a magnon frequency comb(MFC)can be generated in a hybrid magnon-skyrmion system.When the system is driven by two microwave fields at the magnonic whispering gallery mode(m WGM)and the skyrmion,the skyrmion can be simultaneously entangled with three magnon modes of the MFC and the entanglement of the first-order magnon pair in the MFC also appears.The results show that the perfect one-way steering between the skyrmion and the three magnons can be obtained.Interestingly,the steering direction can be manipulated by controlling the amplitudes of two drive fields,which provides flexibility in controlling the asymmetry of the EPR steering and may well have practical applications.Moreover,the genuine tripartite entanglement among the skyrmion and the first-order magnon pair can be achieved with appropriate parameters in the steady state.Our work exhibits that the MFC has great potential in preparing multi-mode entanglement resources,with promising applications in quantum communication. 展开更多
关键词 multipartite entanglement one-way steering magnon frequency comb SKYRMION
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Enhancing entanglement and steering in a hybrid atom–optomechanical system via Duffing nonlinearity
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作者 Ling-Hui Dong Xiao-Jie Wu +1 位作者 Cheng-Hua Bai Shao-Xiong Wu 《Chinese Physics B》 2025年第2期124-131,共8页
We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system... We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity,leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system's resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies. 展开更多
关键词 quantum entanglement EPR steering optomechanical system Duffing nonlinearity
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