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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

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

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Chinese journal 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 saturation.First,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 subtraction.Then,we design a controller to realize the MSS on SO(3)with attitude consensus and attitude stabilization under stochastic links failure and actuator saturation.Finally,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

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

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journal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： jian Liu Anders jLindstrom 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 ecology.However,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately explored.Cycads are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the tropics.Intriguingly,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely elusive.Here,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 cycads.We 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 pattern.We found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental Asia.Different 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 cradles.Moreover,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 equator.Notably,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity pattern.This 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

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

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journal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.Stephen chris R.Burke jennie 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 precisely.Examples include time-dependent traits such as reproductive status,or lifespan.Incomplete measures for these traits result in phenotypes that are subject 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 respectively.Here 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 trait.Methods We produced AGEP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×jersey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New Zealand.We 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 visits.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 approach.Results Credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was reduced.For 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 0.95.The estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring increased.Conclusion Our results indicate that using some methods,phenotypes derived from one observ

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

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 Ahuja Kunal joshi chris Coldham Paulo Muiesan Bobby Dasari Manuel Abradelo Ravi Marudanayagam Darius Mirza john 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 objective 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 unresectable.The 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 necessary.Vascular 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 tumors.Thus,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 major hepatic veins.

关键词： hepatectomy surgery mortality

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

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journal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas Konrad Shahab Alizadeh Abdolhamid Daneshjoo Saman Hadjizadeh 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 Injuries 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 joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,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 training.Methods: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 meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results: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 stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields.

关键词： Flexibility Long-term stretching Stretch training

high-repetition-rate laser-driven fusion;laser±plasma interaction;liquid target;neutron detectors

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High Power Laser Science and Engineering 2024年第1期12卷 13-23页

作者： Benjamin M.Knight Connor M.Gautam Colton R.Stoner Bryan V.Egner joseph R.Smith chris M.Orban juan j.Manfredi Kyle D.Frische Michael L.Dexter Enam A.Chowdhury Anil K.Patnaik Department of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics Department Marietta CollegeMariettaOHUSA Department of Physics The Ohio State UniversityColumbusOHUSA Department of Materials Science and Engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mj, 40 fs laser pulses on a thin(<1 μm) D_2O liquid sheet employing a measurement suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mj, 40 fs laser pulses on a thin(j-309 organic scintillator with pulse-shape discrimination, a ~3He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 MeV. Particle-in-cell simulations using the WarpX code support significant neutron production from D-D fusion events in the laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasma interaction liquid target neutron detectors

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领导为何不公?领导不公行为的形成机理

中国人力资源开发 2024年第1期41卷 112-124页

作者：陈思璇张春红段光卫旭华 chris M.Bell 南京理工大学经济管理学院南京210094 兰州大学管理学院兰州730000 湖南师范大学商学院长沙410081 约克大学舒立克商学院多伦多M3J1P3

领导不公行为是领导者违背公平准则的行为表现,对员工心理及行为的影响不容忽视。已有组织公平的研究广泛证实了领导不公行为对组织所造成的严重后果,但对领导不公行为的前因缺乏系统性的认知。为了全面系统地呈现领导不公行为形成的内... 详细信息

领导不公行为是领导者违背公平准则的行为表现,对员工心理及行为的影响不容忽视。已有组织公平的研究广泛证实了领导不公行为对组织所造成的严重后果,但对领导不公行为的前因缺乏系统性的认知。为了全面系统地呈现领导不公行为形成的内在逻辑,通过对相关文献的梳理,本文阐述了领导不公行为的内涵,对领导不公行为的相似构念进行了辨析,从道德正义理论、社会交换理论、态度功能理论、攻击性社会交互理论、自我损耗理论、自我概念维持理论的视角回顾了领导不公行为形成的理论解释,将领导不公行为归纳为不知而为的无意识不公以及知之而为的有意识不公两种基本模式。最后,从权威的视角切入,基于信息加工理论描述了领导者做出不公行为的信息加工过程,从自动化加工和系统化加工两方面详细讨论了领导不公行为的差异化形成机理,发展了一个形成机理模型。研究有助于推动领导不公行为的理论构建,为管理者做出有效的管理策略来减少领导不公行为提供实践启示。

关键词：领导不公行为信息加工理论组织公平

Most ankle sprain research is either false or clinically unimportant:A 30-year audit of randomized controlled trials

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journal of Sport and Health Science 2021年第5期10卷 523-529页

作者： chris M.bleakley Mark Matthews james M.Smoliga School of Health Science Ulster UniversityCounty AntrimNorthern IrelandBT370QBUK School of Sport Ulster UniversityCounty AntrimNorthern IrelandBT370QBUK Department of Physical Therapy Congdon School of Health ScienceHigh Point UniversityHigh PointNC 27268USA

Background:Lateral ankle sprain is the most common musculoskeletal injury.Although clinical research in this field is growing,there is a broader concern that clinical trial outcomes are often false and fail to translate into patient benefits.Methods:We audited 30 years of experimental research related to lateral ankle sprain management(n=74 randomized controlled trials)to determine if reports of treatment effectiveness could be validated beyond statistical certainty.Results:A total of 77%of trials reported positive treatment effects,but there was a high risk of false discovery.Most trials were unregistered and relied solely on statistical significance,or lack of statistical significance,rather than on interpreting key measures of minimum clinical importance(e.g.,minimal detectable change,minimal clinically important difference).Conclusion:Future clinical trials must adopt higher standards of reporting and data interpretation.This includes consideration of the ethical responsibility to preregister their research and interpretation of clinical outcomes beyond statistical significance.

关键词： Ankle sprain False discovery MCID MDC