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Journal of Rare Earths 2024年第9期42卷 1646-1651,I0001页

作者： Biao Zhou Xiangtong Zhang Ranran Hu Ruixue Hou william w.Yu Key laboratory for Special Functional Materials of Ministry of Education National&Local Joint Engineering Research Centre for High-Efficiency Display and Lighting TechnologySchool of Materials and EngineeringCollaborative Innovation Centre of Nano Functional Materials and ApplicationsHenan UniversityKaifeng475000China School of chemistry and chemical Engineering Shandong UniversityJinan250100China

Metal halide perovskites exhibit promising prospect in light-emitting diodes,solar cells,photodetectors and ***,the workhorse of metal halide perovskites relies on toxicity lead element,which severely damages human body and *** lead-free perovskites,cs_(2)NaIncl_(6)double perovskite is one of the most promising candidates because of its great stability and easy synthesis,but suffers inadequate optical ***,we doped Sb^(3+)and Sm^(3+)into cs_(2)NaIncl_(6)nanocrystals by a hot injection ***_(2)NaIncl_(6):Sb^(3+)exhibits blue emission at 447 ***_(2)NaIncl_(6):Sm^(3+),Sb^(3+)nanocrystals simultaneously generate the blue emission of Sb^(3+)and the multiple emissions of Sm^(3+)at 565,602,650 and 710 *** the increase of Sm^(3+)feed ratio,the emission color of cs_(2)NaIncl_(6):Sm^(3+),Sb^(3+)gradually moves to cold white region at(0.27,0.28)in cIE chromaticity diagram and correlated color temperature of 11840 *** work shows the potential application of cs_(2)NaIncl_(6):Sm^(3+),Sb^(3+)nanocrystals as a single-component cold white emitter.

关键词： lead-free Double perovskites Single component white emitter Doping Rare earths

Plant grafting:Molecular mechanisms and applications

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Molecular Plant 2024年第1期17卷 75-91页

作者： Ming Feng Frauke Augstein Abdul Kareem charles w.Melnyk Department of Plant Biology Linnean Center for Plant BiologySwedish University of Agricultural SciencesAlmas allé575651 UppsalaSweden

People have grafted plants since antiquity for propagation,to increase yields,and to improve stress *** cutting and joining of tissues activates an incredible regenerative ability as different plants fuse and grow as *** over a hundred years,people have studied the scientific basis for how plants ***,new techniques and a deepening knowledge of the molecular basis for graft formation have allowed a range of previously ungraftable combinations to ***,we review recent developments in our understanding of graft formation,including the attachment and vascular formation *** analyze why plants graft and how biotic and abiotic factors influence successful *** also discuss the ability and inability of plants to graft,and how grafting has transformed both horticulture and fundamental plant *** our knowledge about plant grafting improves,new combinations and techniques will emerge to allow an expanded use of grafting for horticultural applications and to address fundamental research questions.

关键词： plant grafting regeneration mobile molecules tissue adhesion vascular differentiation stress tolerance

Prehospital transdermal glyceryl trinitrate for ultra- acute ischaemic stroke: data from the RIGHT- 2 randomised sham- controlled ambulance trial

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Stroke & Vascular Neurology 2024年第1期9卷 38-49,I0035-I0046页

作者： Jason Philip Appleton lisa J woodhouse craig S Anderson Sandeep Ankolekar lesley cala Mark Dixon Timothy J England Kailash Krishnan Grant Mair Keith w Muir John Potter christopher I Price Marc Randall Thompson G Robinson christine Roffe Else c Sandset Jeffrey l Saver Angela Shone Aloysius Niroshan Siriwardena Joanna M wardlaw Nikola Sprigg Philip M Bath Stroke University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Applied HealthResearch University of Birmingham College of Medical and Dental SciencesBirminghamUK Stroke Trials unit Mental Health and Clinical NeurosciencesUniversity of NottinghamNottinghamUK Faculty of Medicine The George Institute for Global HealthSydneyNew South WalesAustralia The George Institute china at Peking university Health Science center BeijingChina Neurology Royal Prince Alfred HospitalSydney Health PartnersSydneyNew South WalesAustralia Department of Neurology King's College Hospital NHS Foundation TrustLondonUK Faculty of Health and Medical Sciences University of Western AustraliaCrawleyWestern AustraliaAustralia East Midlands Ambulance Service NHS Trust NottinghamUK Stroke Queen's Medical CentreNottingham University Hospitals NHS TrustNottinghamUK centre for clinical Brain Sciences Dementia Research InstituteUniveristy of EdinburghEdinburghUK Institute of Neurology and Psychology University of GlasgowGlasgowUK Bob champion Research and Education Building University of East AngliaNorwichUK Institute of Neuroscience Newcastle UniversityNewcastle upon TyneUK Department of Neurology Leeds Teaching Hospitals NHS TrustLeedsUK Department of cardiovascular Sciences and NIHR leicester Biomedical Research centre University of LeicesterLeicesterUK Stroke Research in Stoke Institute for Science and Technology in MedicineKeele UniversityStoke-on TrentUK Department of Neurology Oslo University HospitalOsloNorway Research and Development Norwegian Air Ambulance FoundationOsloNorway Department of Neurology and comprehensive Stroke center David Geffen School of MedicineUCLALos AngelesCaliforniaUSA Research and Graduate Services University of NottinghamNottinghamUK community and Health Research unit University of LincolnLincolnUK

Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is ***,we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2(RIGHT-2).Methods RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4hours of *** primary outcome was a shift in scores on the modified Rankin scale(mRS)at day *** outcomes included death;a global analysis(wei-lachin test)containing Barthel Index,EuroQol-5D,mRS,telephone interview for cognitive status-modified and Zung depression scale;and neuroimaging-determined‘brain frailty’*** were reported as n(%),mean(SD),median[IQR],adjusted common OR(acOR),mean difference or Mann-whitney difference(MwD)with 95%*** 597 of 1149(52%)patients had a final diagnosis of ischaemic stroke;age 75(12)years,premorbid mRS>2107(18%),Glasgow coma Scale 14(2)and time from onset to randomisation 67[45,108]***‘brain frailty’was common:median score 2[2,3](range 0–3).At day 90,GTN did not influence the primary outcome(acOR for increased disability 1.15,95%cI 0.85 to 1.54),death or global analysis(MwD 0.00,95%cI-0.10 to 0.09).In subgroup analyses,there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1hour of symptom onset and in those with more severe *** In patients who had an ischaemic stroke,ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital *** IS AlREADY KNOwN ON THIS TOPIc⇒Transdermal glyceryl trinitrate(GTN)was associat-ed with less death and dependency in those w

关键词： Glasgow nitrate random

Distributed swarm control for multi-robot systems inspired by shepherding behaviors

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Science china(Technological Sciences) 2024年第7期67卷 2191-2202页

作者： SuN GuiBin Gu HaiBo lÜJinHu School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Zhongguancun laboratory Beijing 100094China

Swarming behaviors play an eminent role in both biological and engineering research, and show great potential applications in many emerging fields. Traditional swarming models still lack integrity, uniformity, and stability in swarm forming processes,resulting in fragmentation and void phenomena. Inspired by the shepherding behaviors observed in nature, we propose an integrated negotiation-control scheme for distributed swarm control of massive robots. The core idea of this scheme is that the robots at the boundary of the group herd the internal robots to form an equilibrium swarm. For this purpose, we introduce a concept of virtual group center towards which boundary robots herd internal robots. Then, a distributed negotiation mechanism is designed to allow each robot to negotiate the virtual group center only through local interactions with its neighbors. After that, we propose a shepherding-inspired swarm control law to drive a group of robots to form an integrated, uniform, and stable configuration from any initial states. Both numerical and flight simulations are presented to verify the effectiveness of our proposed swarm control scheme.

关键词： swarm control multi-robot system negotiation-control scheme shepherding behavior

Effective yield strength of a saturated porous medium with a spheroidal meso-pore and spherical micro-pores

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第1期3卷 97-104页

作者： w.Q.Shen college of Architecture and Energy Engineering Wenzhou University of TechnologyWenzhou325000China Department of civil Engineering Polytech LilleUniversity of LilleFrance

A macroscopic yield criterion has been derived in the present work for a double saturated porous medium with a spheroidal pore at the mesocale and spherical pores at the *** two types of pores are well separated at two different *** meso spheroidal pore saturated by a pore pressure which is different from the one in the micro spherical pores.A Drucker-Prager type criterion is adopted for the solid phase at the microscopic scale to describe its asymmetric behavior between tension and *** methodology to formulate this criterion is based on the limit analysis approach of a spheroidal volume containing a confocal spheroidal pore subjected to a uniform strain rate boundary *** matrix at the mesoscopic scale obeys to a general elliptic yield *** on a two-step homogenization step,the influence of meso-pore shape(spherical,prolate or oblate),micro-porosity,meso-porosity and the effect of pore pressures at different scales are taken into account explicitly by this macroscopic yield criterion.

关键词： Double porous materials Saturated Spheroidal pore Macroscopic yield criterion Plasticity Gurson-type model

Promoting Older Adults' Engagement in Disaster Recovery Through Supportive Relationships, Partnerships, and collaboration: Perspectives of Social work Practitioners and Human Service Professionals

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International Journal of Disaster Risk Science 2024年第2期15卷 265-276页

作者： Julie l.Drolet Mahed choudhury Faculty of Social work University of CalgaryEdmontonAB T5J 4P6Canada

Shifting demographics—that is, the growing number of older adults in canada and internationally—and intersecting climatic risks create a complex landscape of aging in place in disaster contexts. Some older adults are vulnerable due to their underlying health conditions and limited physical mobility. Yet they also exhibit resilience in a distinct manner, owing to their wealth of knowledge, wisdom, and ability to navigate adversities. This article elucidates potential avenues for promoting the involvement of older adults in disaster recovery efforts. Our intention is to recognize and foster older adult resilience and mitigate vulnerability by drawing upon insights from the study titled “In the Aftermath of the 2016 Alberta wildfires: The Role of Social work Practitioners and Human Service Professionals in long-Term Disaster Recovery.” Employing a qualitative research approach, that study recruited 51 participants for semistructured interviews and focus groups. A thematic analysis of the collected data unveiled the pivotal roles played by social workers and human service practitioners in facilitating recovery from the 2016 wildfires in the research. Notably, three overarching themes emerged concerning the promotion of older adults' involvement in disaster recovery: fostering supportive relationships, building partnerships and enhancing collaboration, and addressing ongoing challenges. These findings offer valuable insights into how social work practitioners and human service professionals can effectively facilitate the engagement of older adults in disaster recovery initiatives. This article emphasizes the significance of actively promoting the participation of older adults in disaster mitigation efforts, thereby fostering greater resilience within communities.

关键词： Alberta wildfires canada Disaster recovery Older adults Partnerships and collaboration Social work

Recent Advances in catalytic carbonylation Reactions in Alternative Reaction Media

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chinese Journal of chemistry 2024年第4期42卷 406-429页

作者： csaba Árvai lászló T.Mika Department of chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of c=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVl),2-methyltetrahydrofuran(2-MeTHF),ionic liquids(Ils),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： carbonylation catalysis Solvents Green chemistry carbon monoxide Transition metals Homogeneous catalysis Palladium

Stability and performance analysis of the compressed Kalman filter algorithm for sparse stochastic systems

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Science china(Technological Sciences) 2024年第2期67卷 380-394页

作者： lI RongJiang GAN Die XIE SiYu lüJinHu Key laboratory of Systems and control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun laboratory Beijing 100049China School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic *** deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)*** algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional ***,the original high-dimensional sparse signals can be well recovered by a reconstruction *** ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and ***,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.

关键词： sparse signal compressed sensing Kalman filter algorithm compressed excitation condition stochastic stability tracking performance

Population dynamics of the tropical oyster Magallana bilineata(Mollusca,Bivalvia,Ostreidae)in Mengkabong Bay,Tuaran,Malaysia

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Aquaculture and Fisheries 2024年第2期9卷 295-305页

作者： Joanna w.Doinsing Julian Ransangan Politeknik Sandakan Sabah Education HubBatu 10Jalan Sungai BatangSandakanSabah90000Malaysia Borneo Marine Research Institute Universiti Malaysia SabahJalan UMSKota Kinabalu88400Malaysia

Knowledge about the population dynamics within a specific spatial area is vital for the effective planning and management of important fishery *** parameters,including the asymptotic length(l∞),growth coefficient(K),mortalities(Z,F,and M),recruitment pattern,exploitation level(E),and yield per recruit(Y’/R),of the tropical oyster Magallana bilineata in Mengkabong Bay,Tuaran,Malaysia were analyzed by using the FiSAT software,using on the monthly shell length-frequency data collected from April 2019 to March 2020.A total of 435 oysters with shell lengths ranging from 3.64 to 11.16 cm were *** water temperature,salinity,dissolved oxygen,hydrogen ion concentration(pH),and chlorophyll concentration were measured at 29.0-33.7◦c,26.68-35.74 psμ,3.18-6.99 mg/l,6.57-8.29 and 1.51-98.93μg/l,*** logarithmic relationship between the length and weight of log w=1.9055 log l+0.1049(R2=0.5431)with exponent b of 1.9055 for combined sexes showed a negative allometric growth(bcating that the oysters in Mengkabong Bay are *** management measures have been proposed to promote high meat growth,including the use of genetically selected seeds,selection of new farming sites and adoption of grow-out methods that favour high meat *** length(l∞)and growth coefficient(K)of the von Bertalanffy Growth Formula(VBGF)for *** were estimated at 12.13 cm and 1.00 yr􀀀1,*** theoretical ages at length zero(t0)(0.0487)were estimated by substituting l∞and K in Pauly’s *** sizes attained by *** were 3.76,5.04,6.13,7.05,7.83,and 8.49 cm at the end of 2,4,6,8,10,and 12 months,*** calculated growth performance index(φ)for *** in Mengkabong Bay was 2.168,while the estimated lifespan was 3 *** recruitment pattern was observed year-round,with higher recruitment activities in September-October 2019 and January *** total mortality(Z)was analyzed using the length-converted

关键词： crassostrea iredalei length-weight relationship Growth parameters Recruitment Exploitation

Neural-network-based fully distributed formation control for nonlinear multi-agent systems with event-triggered communication

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Science china(Technological Sciences) 2024年第1期67卷 209-220页

作者： ZHu Guoliang lIu KeXin Gu HaiBo lÜJinHu School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Zhongguancun laboratory Beijing 100094China

This paper investigates the consensus-based formation control problem for multi-agent systems with unknown nonlinear *** achieve the desired formation,we propose two formation controllers to achieve the desired formation,one based on system states and the other on system *** proposed controllers utilize adaptive gains to avoid global information and neural networks to estimate and compensate for *** proposed event-triggered schemes avoid continuous communication among agents and exclude the Zeno *** analysis reveals that formation errors are bounded,and numerical simulations are used to validate the effectiveness of the proposed approaches.

关键词： formation control neural network adaptive control event-triggered communication multi-agent systems