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Attitude control of multi-spacecraft systems on SO(3)with stochastic links failure

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Chinese j.urnal of Aeronautics 2024年第3期37卷 320-331页

作者： KANG Zeyu SHEN Qiang WU Shufan chris j.DAMAREN MU Zhongcheng School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Institute for Aerospace Studies University of TorontoTorontoOntario M3H 5T6Canada

In this paper,for Multi-Spacecraft System(MSS)with a directed communication topology link and a static virtual leader,a controller is proposed to realize attitude consensus and attitude stabilization with stochastic links failure and actuator ***,an MSS attitude error model suitable for a directed topology link and with a static virtual leader based on SO(3)is derived,which considers that the attitude error on SO(3)cannot be defined based on algebraic ***,we design a controller to realize the MSS on SO(3)with attitude consensus and attitude stabilization under stochastic links failure and actuator ***,the simulation results of a multi-spacecraft system with stochastic links failure and a static virtual leader spacecraft are demonstrated to illustrate the efficiency of the attitude controller.

关键词： Multi-spacecraft systems Attitude consensus Attitude stabilization Stochastic links failure Super-martingale convergence

Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma chris j.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

Eco-evolutionary evidence for the global diversity pattern of Cycas(Cycadaceae)

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j.urnal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： j.an Liu Anders j.indstrom Yiqing Gong Shanshan Dong Yusheng(chris)Liu Shouzhou Zhang Xun Gong CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Global Biodiversity Conservancy 144/124 Moo3Soi Bua ThongBangsalaeSattahipChonburi 20250Thailand Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004China Department of Earth and Environmental Sciences Indiana University-IndianapolisIndianapolisIN 46202USA

The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ***,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately *** are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the ***,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely ***,using 1,843 nuclear genes from a nearly complete sampling,we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas,the largest genus within *** then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages,diversification rates,contemporary environment,and conservatism to ancestral niches in shaping the i-LDG *** found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental *** regions have distinctively contributed to the formation of i-LDG for Cycas,with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as ***,water-related climate variables,specifically precipitation seasonality and potential evapotranspiration,were identified as paramount factors constraining Cycas species richness in the rainforest biome near the ***,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity *** study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

关键词： cycads latitudinal diversity gradient niche conservatism spatiotemporal diversification species richness

Experimental and analytical investigation on friction resistance force between buried coated pressurized steel pipes and soil

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 615-629页

作者： Shaurav ALAM Tanvir MANZUR j.hn MATTHEWS chris BARTLETT Erez ALLOUCHE Brent KEIL j.hn KRAFT Department of Civil Engineering and Construction Engineering Technology Louisiana Tech UniversityRustonLA 71270USA Department of Civil Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh Georgia Tech Research Institute AtlantaGA 30332USA Stantec Inc. Edmonton T5J0K4Canada North West Pipe Company VancouverWA 98684USA

This paper presents an analytical approach for estimating frictional resistance to pipe movement at soil and external pipe surface of buried coated pressurized steel pipes relative to the internal thrust *** proposed analytical method was developed based on 36 experiments,which involved three coating types(cement mortar(CM),polyurethane type-I(PT-I),prefabricated plastic tape(PPT))on pipes’surfaces,three different soils(pea-gravel(PG),sand(S),silty-clay(SC)),and four simulated over burden depths above the pipe’s *** showed frictional resistance decreased with increasing over burden depth above the pipe’s *** degree of frictional resistance at the pipe-soil interface was found to be in the order of PG>SC>S for all coating variations and overburden *** coated pipe buried in all three types of soil produced significantly higher frictional resistance as compared to other coating *** on experimental data,the developed analytical introduced a dimensionless factor“Z”,which included effects of types of coatings,soil,and overburden depths for simplified rapid *** showed that the method provided a better prediction of frictional resistance forces,in comparison to previous analytical methods,which were barely close in predicting friction resistance for different coating variations,soil types,and overburden *** resistance force values reported herein could be considered conservative.

关键词： friction resistance force thrust force coated pressurized steel pipe soil type overburden depth

Comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

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j.urnal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.Stephen chris R.Burke j.nnie E.Pryce Nicole M.Steele Peter R.Amer Susanne Meier Claire V.C.Phyn Dorian j.Garrick DairyNZ Ltd 605 Ruakura RoadHamilton 3240New Zealand AL Rae Centre for Genetics and Breeding-Massey University RuakuraHamilton 3214New Zealand Agriculture Victoria Research AgriBioCentre for AgriBioscienceBundooraVictoria 3083Australia School of Applied Systems Biology La Trobe UniversityBundooraVictoria 3083Australia AbacusBio DunedinNew Zealand

Background Many phenotypes in animal breeding are derived from incomplete measures,especially if they are challenging or expensive to measure *** include time-dependent traits such as reproductive status,or *** measures for these traits result in phenotypes that are subj.ct to left-,interval-and rightcensoring,where phenotypes are only known to fall below an upper bound,between a lower and upper bound,or above a lower bound *** we compare three methods for deriving phenotypes from incomplete data using age at first elevation(>1 ng/mL)in blood plasma progesterone(AGEP4),which generally coincides with onset of puberty,as an example *** We produced AGEP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×j.rsey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New *** used these actual data to simulate 7 different visit scenarios,increasing the extent of censoring by disregarding data from one or two of the three *** methods for deriving phenotypes from these data were explored:1)ordinal categorical variables which were analysed using categorical threshold analysis;2)continuous variables,with a penalty of 31 d assigned to right-censored phenotypes;and 3)continuous variables,sampled from within a lower and upper bound using a data augmentation *** Credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was *** sires with at least 5 daughters,the correlations between estimated breeding values(EBVs)from our three-visit scenario and each reduced data scenario varied by method,ranging from 0.65 to *** estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring *** Our results indicate that using

关键词： Cattle Gibbs sampler Markov-chain Monte Carlo(MCMC) Puberty

Individual consistency in spatiotemporal characteristics of migratory Whimbrels in the East Asian-Australasian Flyway

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Avian Research 2024年第3期15卷 308-315页

作者： Siwei An Fenliang Kuang Wei Wu chris j.Hassell j.nathan T.Coleman Zij.ng Gao Xuena Sun Yue Yuan Grace Maglio Kar-Sin K.Leung Xuesong Feng Zhij.n Ma Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Coastal Ecosystems Research Station of the Yangtze River EstuaryInstitute of Biodiversity ScienceSchool of Life SciencesFudan UniversityShanghai200433China School of Chemistry and Environment Yunnan Minzu UniversityKunming650504China Shanghai Chongming Dongtan Nature Reserve Administration Center ChongmingShanghai202183China Global Flyway Network PO Box 3089BroomeWA 6725Australia Australasian Wader Studies Group BroomeWA6725Australia Queensland Wader Study Group Shailer ParkQLD4128Australia Hong Kong Waterbirds Ringing Group Hong Kong999077China

Many migratory birds exhibit interannual consistency in migration schedules,routes and stopover *** the interannual consistency in spatiotemporal characteristics helps understand the maintenance of migration and enables the implementation of targeted conservation *** tracked the migration of Whimbrel(Numenius phaeopus)in the East Asian-Australasian Flyway and collected spatiotemporal data from individuals that were tracked for at least two *** non-parametric tests were used to compare the interannual variations in the dates of departure from and arrival at breeding/nonbreeding sites,and the inter-annual variation in the longitudes when the same individual across the same *** exhibited a high degree of consistency in the use of breeding,nonbreeding,and stopover sites between *** variation of arrival dates at nonbreeding sites was significantly larger than that of the departure dates from nonbreeding and breeding *** used stopover sites by the same individuals in multiple years were concentrated in the Yellow Sea coast during northward migration,but were more widespread during southward *** stopover duration at repeatedly used sites was significantly longer than that at sites used only *** flying across the Yellow Sea,Whimbrels breeding in Sakha(Yakutia)exhibited the highest consistency in migration routes in both autumn and ***,the consistency in migration routes of Yakutia breeding birds was generally higher than that of birds breeding in *** results suggest that the northward migration schedule of the Whimbrels is mainly controlled by endogenous factors,while the southward migration schedule is less affected by endogenous *** repeated use of stopover sites in the Yellow Sea coast suggests this region is important for the migration of Whimbrel,and thus has high conservation value.

关键词： Consistency Migration route Migration timing Shorebird

Hepatic vein reconstruction during hepatectomy:A feasible and underused technique

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 421-427页

作者： Manish Ahuj. Kunal j.shi chris Coldham Paulo Muiesan Bobby Dasari Manuel Abradelo Ravi Marudanayagam Darius Mirza j.hn Isaac David Bartlett Nikolaos A Chatzizacharias Robert P Sutcliffe Keith j.Roberts Department of HPB and Liver Transplant Surgery University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Immunology and Immunotherapy University of BirminghamBirminghamUK

Complete surgical resection(R0)of liver tumors,primary or metastatic,remains the main obj.ctive in management of primary and metastatic liver tumors[1].Tumors invading to the proximity of the hepatic venous outflow pose a peculiar challenge to achieve R0 resections,because this location may render a tumor *** median survival of patients with liver tumor without surgery is less than 12 months[2].Even with surgery,post-hepatectomy liver failure and subsequently increased mortality are the main problems associated with complex resection[3].Moreover,when the vein is affected,vein resection and subsequent reconstruction are *** resection is a standard practice in liver resection and transplantation[4],for example,hepatic vein reconstruction during a living-donor liver transplant,porto-mesenteric axis reconstruction during resection of advanced pancreatic cancer and caval reconstruction during resection of retroperitoneal ***,novel techniques like total hepatic vascular exclusion(HVE)[5],veno-venous bypass[6]and ex vivo hepatic resection[7,8]have facilitated curative resections of tumors close to one or more maj.r hepatic veins.

关键词： hepatectomy surgery mortality

The Effects of Zinc Sulfate on the in Vitro Digestibility of Feeds in Cervids

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Open j.urnal of Animal Sciences 2024年第3期14卷 157-167页

作者： Reese j. Thibodeaux Philip M. Urso Stanley F. Kelley Marcy M. Beverly chris R. Stewart Ian C. Dunn Gentech Diagnostics Dallas Texas USA Department of Animal Science South Dakota State University Brookings South Dakota USA School of Agricultural Sciences Sam Houston State University Huntsville Texas USA 3-S Texas Outdoors/3-S Whitetails Bedias Texas USA

The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The obj.ctive of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying CO2. Fluid was placed into four separate incubator j.rs with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the j.rs ( Zn), and the additional two j.rs received 0.00 mg/kg/d (CON). Following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in ADF, NDF, IVTD, or OM between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.

关键词： Zinc IVDMD In Vitro Cervids

Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

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j.urnal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas Konrad Shahab Alizadeh Abdolhamid Daneshj.o Saman Hadj.zadeh Anvar Andrew Graham Ali Zahiri Reza Goudini chris Edwards Carina Scharf David George Behm Institute of Human Movement Science Sport and HealthGraz UniversityGraz A-8010Austria School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada Department of Sport Inj.ries and Corrective Exercises Faculty of Sport SciencesShahid Bahonar University of KermanKerman 76169-13439Iran

Background:It is well known that stretch training can induce prolonged increases in j.int range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in ***,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch ***:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect ***,by applying a mixed-effect model,we performed the respective subgroup *** find potential relationships between stretch duration or age and effect sizes,we performed a ***:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic ***,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to ***,further moderating analysis showed no significant relation or ***:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be *** to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were

关键词： Flexibility Long-term stretching Stretch training