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Output feedback adaptive super twisting sliding mode control for quadrotor UAVs

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Control Theory and Technology 2024年第1期22卷 92-105页

作者： Oscar Salas-peña Jesus DeLeón-Morales Susana V.Gutiérrez-Martínez École Centrale de Nantes-LS2N UMR 6004 CNRS44300NantesFrance Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo León66451San Nicolás de Los GarzaMexico

In this paper, a sliding mode control with adaptive gain combined with a high-order sliding mode observer to solve the tracking problem for a quadrotor UAV is addressed, in presence of bounded external disturbances and parametric uncertainties. The high order sliding mode observer is designed for estimating the linear and angular speed in order to implement the proposed sche.e. Furthermore, a Lyapunov function is introduced to design the controller with the adaptation law, whereas an analysis of finite time convergence towards to zero is provided, where sufficient conditions are obtained. Regarding previous works from literature, one important advantage of proposed strategy is that the gains of control are parameterized in terms of only one adaptive parameter, which reduces the control effort by avoiding gain overestimation. Numerical simulations for tracking control of the quadrotor are given to show the performance of proposed adaptive control–observer sche.e.

关键词： Adaptive super twisting controller High-order sliding modes observer UAV

Reproductive patterns in Araucaria araucana forests in the Andean range, Chile

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Ecological Processes 2024年第01期13卷 252-261页

作者： Sergio Donoso Karen pe?a-Rojas Claudia Espinoza Carolain Badaracco Rómulo Santelices-Moya Antonio Cabrera-Ariza Mediterranean Forests Laboratory Faculty of Forestry and Nature Conservation Centro Secano Faculty of Agricultural and Forestry Sciences Universidad Católica del Maule Maule Advanced Studies Research Center Vice-Rector's Office for Research and Postgraduate Studies Catholic University of Maule

Background Araucaria araucana is a mast species that presents a high variability in annual cone production. Researche.s have recorded synchronization events in cone production in different populations, which allows the seed production to be concentrated, reducing the percentage of seeds consumed by different animal *** We sampled three populations located in the Andes Mountains, Araucanía Region, Chile. In 2004 we began the collection of data on cone production, for which we installed permanent plots（1200 m2each） at each location. We identified and labeled each female tree in each plot to monitor its cone production. In 2012 we selected a total of 30 trees near the plots to evaluate the number of seeds per cone. In each February from 2012 to 2014 we selected two mature cones and covered them with a porous mesh for subsequent collection and storage in March. At the beginning of June, we counted and weighed the seeds, determining the average weight, the number of seeds per cone, the germination capacity（GC）, and the germination speed（GS）.Results Cone production was synchronous across the three locations. We observed significant differences among the locations and years evaluated. The cones had fewer seeds in 2013（high production） compared to those in 2012（low production）, but their weights were similar. In 2014 the cones produced smaller seeds in fewer quantities. The difference between the years 2013 and 2014 resulted from the high-energy expenditure in 2013. Regarding GC and GS, there were significant differences among the three locations（GC: F = 45.41, p pecies. Our results allow a better understanding of the reproductive phenology of A. araucana and could hel

关键词： Seed weight Germination potential Masting species Sustainable use Dioecious species

Oxidative degradation and upcycling of polyethylene wastes

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Science China che.istry 2024年

作者： Yizhen che.Yanfen Wu Zhiqiang Niu State Key Laboratory of che.ical Engineering Department of Chemical Engineering Tsinghua University Ordos Laboratory

Plastics have become omnipresent in modern life due to their versatility and durability. However, this convenience comes at the cost of substantial waste generation. The inherent che.ical stability of plastics complicates its recycling, leading to environmental pollution and ecological threats. This mini-review highlights recent advancements in addressing this challenge by oxidative transformation of polyethylene (pe) into new functional polymers, value-added che.icals, and carbon-based materials. We first discuss the introduction of hydroxyl, carbonyl groups onto pe with a focus on the functionalization degree and selectivity. Subsequently, approache. for pe oxidation into dicarboxylic acids and short-chain oxidized pe are described and compared, with an emphasis on the tandem reactions for converting mixed dicarboxylic acids into other value-added *** also briefly discuss the oxidative transformation of pe into carbon-based materials and summarize the progress in qualitative and quantitative analysis of oxidation products. Finally, we conclude this mini-review by highlighting the challenges and opportunities in the field.

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Hollow FeCoNiAl microspheres with stabilized magnetic properties for microwave absorption

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Nano Research 2024年第3期17卷 2079-2087页

作者： Linhe Yu Gangjie Lian Guozhen Zhu Sue Ren Yanfang Du Xuhui Xiong Rui che. Jincang Zhang Wenbin You Renchao che Institute of Advanced Materials College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438China Zhejiang Laboratory Hangzhou 311100China Capital Aerospace Machinery Corporation Limited Beijing 100000China AECC Beijing Institute of Aeronautical Materials Beijing 100095China International Center for Quantum and Molecular Structures Materials Genome InstitutePhysics DepartmentShanghai UniversityShanghai 200444China

Development of high-performance microwave absorption materials(MAM)with stabilized magnetic properties at high temperatures is specifically essential but remains ***,the Snoke's limitation restrains the microwave absorption(MA)property of magnetic *** alloy components is considered an effective way to solve the aforementioned ***,a hollow medium-entropy FeCoNiAl alloy with a stable magnetic property is prepared via simple spray-drying and two-step annealing for efficient *** exhibited an ultrabroad effective absorption band(EAB)of 5.84 GHz(12.16–18 GHz)at a thickness of just 1.6 mm,revealing an excellent absorption ***,the MA mechanism of FeCoNiAl is comprehensively investigated via off-axis ***,the electromagnetic properties,antioxidant properties,and residual magnetism at high temperatures of FeCoNiAl alloys are summarized in detail,providing new insights into the preparation of MAM operating at elevated temperatures.

关键词： microwave absorption hollow structure magnetic stability multiple microwave absorption mechanism

Assistive Robotics for Upper Limb Physical Rehabilitation: A Systematic Review and Future Prospects

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Chinese Journal of Mechanical Engineering 2024年第4期 63-86页

作者： Andrés Guatibonza Leonardo Solaque Alexandra Velasco Lina pe?uela Department of Engineering Mechatronics EngineeringMilitar Nueva Granada University

Physical assistive robotics are oriented to support and improve functional capacities of people. In physical rehabilitation, robots are indeed useful for functional recovery of affected limb. However, there are still open questions related to technological aspects. This work presents a systematic review of upper limb rehabilitation robotics in order to analyze and establish technological challenges and future directions in this area. A bibliometric analysis was performed for the systematic literature review. Literature from the last six years, conducted between August 2020 and May 2021,was reviewed. The methodology for the literature search and a bibliometric analysis of the metadata are *** a preliminary search resulted in 820 articles, a total of 66 articles were included. A concurrency network and bibliographic analysis were provided. And an analysis of occurrences, taxonomy, and rehabilitation robotics reported in the literature is presented. This review aims to provide to the scientific community an overview of the state of the art in assistive robotics for upper limb physical rehabilitation. The literature analysis allows access to a gap of unexplored options to define the technological prospects applied to upper limb physical rehabilitation robotics.

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Porphyrins,phthalocyanines,and related covalent-organic frameworks in the photoche.ical and electroche.ical water splitting:A review

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Particuology 2024年第7期90卷 236-265页

作者： Oxana V.Kharissova Yolanda peña Méndez Boris I.Kharisov Aleksandr LNikolaev Edith Luévano-Hipólito Lucy T.González Universidad Autónoma de Nuevo León Ave.Universidad s/nSan Nicolás de los GarzaNuevo León66455Mexico Department of che.istry Moscow State UniversityVorobievy HillsMoscowRussia CONACYT-Universidad Autónoma de Nuevo León Facultad de Ingeniería Civil-Departamento de Ecomateriales y EnergíaCd.UniversitariaC.P.66455San Nicolás de los GarzaNLMexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo León 64890Mexico Tecnologico de Monterrey Centro del AguaMonterreyNuevo León 64890Mexico

In this review,the possibilities of photoche.ical and electroche.ical water splitting(WS)using porphyrins,phthalocyanines,related macrocycles,and their metal complexes are *** efforts are being carried out in order to develop novel and che.p methods for water decomposition to generate inexhaustible greener energy sources(molecular hydrogen)instead of oil and *** processes of WS in heterogeneous and homogeneous media require novel photo-and electrocatalysts,in particular those on macrocycle basis.A high WS efficiency has been observed for porphyrins and phthalocyanines,showing their suitability both for HER and OER processes are available using these relative compounds for WS *** can be used in photocatalytic and electrocatalytic WS processes both in their free forms or as metal porphyrins/porphyrinates,mainly loaded on various inorganic materials,such as Au NPs,C_(3)N_(4),GaP,KTaO_(3),GaP,and so on,as part of porphyrin-containing polymers or on electrode surface as modifying coatings,being sometimes better than commercial catalysts,such as Pt/*** H2 evolution can be considerably depended on the shape of porphyrin particles;in particular,porphyrin nanowires can yield up to 20 times more H2 than its *** certain cases,both HER and OER can be driven in the same electrolyte using metal *** capacity of metal porphyrins to generate ROS(in particular,singlet oxygen 1O_(2))under ultrasonic treatment is known and can be successfully used for H_(2)O_(2) and O_(2) *** can be used in similar processes in free form or as composites with inorganic or organic counterparts,being immobilized on nanocarbons,metal oxides and salts,or simply dissolved in water acting in a homogeneous *** additional use of ultrasound can lead to better results due to the synergistic effect of the sonoche.ical treatment and ***-organic frameworks are also applied for WS purposes and are mainly based

关键词： Porphyrins Phthalocyanines COFs Water splitting Photocatalysis Electrocatalysis

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana V.Kharissova Lucy T.González Yolanda peña Méndez Igor E.Uflyand Idalia Gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of che.istry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electroche.ical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,che.ical stability and biocompatibility,as well as possessing antibacterial ***→G reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

Linking leaf elemental traits to biomass across forest biomes in the Himalayas

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Science China Earth Sciences 2024年第5期67卷 1518-1528页

作者： Nita DYOLA Eryuan LIANG Josep peÑUELAS J.Julio CAMARERO Shalik Ram SIGDEL Sugam ARYAL Wentao LIN Xiang LIU Yongwen LIU Xingliang XU Sergio ROSSI State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Laboratoire sur lesécosystèmes terrestres boréaux Département des Sciences FondamentalesUniversitédu QuébecàChicoutimi555Boulevard de l′UniversitéChicoutimi(QC)G7H2B1Canada CSIC Global Ecology Unit CREAF-CSIC-UABBellaterraE-08193 CataloniaSpain CREAF Cerdanyola del VallèsE-08193 CataloniaSpain Instituto Pirenaico de Ecología(Ipe-CSIC) Avenida Montañana 1005Zaragoza 50059Spain Friedrich-Alexander-Universität Erlangen-Nürnberg Institut für GeographieErlangen 91058Germany State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Plants require a number of essential elements in different proportions for ensuring their growth and *** elemental concentrations in leaves reflect the functions and adaptations of plants under specific environmental ***,less is known about how the spectrum of leaf elements associated with resource acquisition,photosynthesis and growth regulates forest biomass along broad elevational *** examined the influence of leaf element distribution and diversity on forest biomass by analyzing ten elements(C,N,P,K,Ca,Mg,Zn,Fe,Cu,and Mn)in tree communities situated every 100 meters along an extensive elevation gradient,ranging from the tropical forest(80 meters above sea level)to the alpine treeline(4200 meters above sea level)in the Kangche.junga Landscape in eastern Nepal *** calculated communityweighted averages(reflecting dominant traits governing biomass,i.e.,mass-ratio effect)and functional divergence(reflecting increased trait variety,i.e.,complementarity effect)for leaf elements in a total of 1,859 trees representing 116 *** increasing mass-ratio effect and decreasing complementarity in leaf elements enhance forest biomass accumulation.A combination of elements together with elevation explains biomass(52.2%of the variance)better than individual elemental trait diversity(0.05%to 21%of the variance).Elevation modulates trait diversity among plant species in biomass *** promotes biomass at lower elevations,but reduces biomass at higher elevations,demonstrating an interaction between elevation and *** interaction between elevation and mass-ratio effect produces heterogeneous effects on biomass along the elevation *** research indicates that biomass accumulation can be disproportionately affected by elevation due to interactions among trait diversities across vegetation *** higher trait variation enhances the adaptation of species to environmental changes,it reduces

关键词： Ecosystem function Elevational gradient Functional diversity Functional traits Leaf elements Niche.complementarity

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Rescue of p53 functions by in vitro-transcribed mRNA impedes the growth of high-grade serous ovarian cancer

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Cancer Communications 2024年第1期44卷 101-126页

作者： Monika Raab Izabela Kostova Samuel peña-Llopis Daniela Fietz Monika Kressin Seyed Mohsen Aberoumandi Evelyn Ullrich Sven Becker Mourad Sanhaji Klaus Strebhardt Department of Gynecology Medical SchoolGoethe-UniversityFrankfurt am MainGermany Translational Genomics in Solid Tumors West German Cancer CenterUniversity HospitalEssenGermany German Cancer Consortium(DKTK) EssenGermany German Cancer Research Center(DKFZ) HeidelbergGermany Histology and Embryology Institute for Veterinary AnatomyGiessenGermany Franfurt Cancer Institute(FCI) Goethe UniversityFrankfurt am MainGermany German Cancer Consortium(DKTK) Partner site Frankfurt/Mainza partnership between DKFZ and University Hospital FrankfurtFrankfurt am MainGermany Experimental Immunology Department for Children and Adolescents MedicineUniversity Hospital FrankfurtGoethe UniversityFrankfurt am MainGermany

Background:The cellular tumor protein p53(TP53)is a tumor suppressor gene that is frequently mutated in human *** various cancer types,the very aggressive high-grade serous ovarian carcinoma(HGSOC)exhibits the high-est prevalence of TP53 mutations,present in>96%of *** intensive efforts to reactivate p53,no clinical drug has been approved to rescue p53 *** this study,our primary objective was to administer in vitro-transcribed(IVT)wild-type(WT)p53-mRNA to HGSOC cell lines,primary cells,and ortho-topic mouse models,with the aim of exploring its impact on inhibiting tumor growth and dissemination,both in vitro and in ***:To restore the activity of p53,WT p53 was exogenously expressed in HGSOC cell lines using a mammalian vector ***,IVT WT p53 mRNA was delivered into different HGSOC model systems(primary cells and patient-derived organoids)using liposomes and studied for proliferation,cell cycle progression,apoptosis,colony formation,and chromosomal *** alterations induced by p53 mRNA were analyzed using RNA sequencing in OVCAR-8 and primary HGSOC cells,followed by ingenuity path-way *** vivo effects on tumor growth and metastasis were studied using orthotopic xenografts and metastatic intraperitoneal mouse ***:Reactivation of the TP53 tumor suppressor gene was explored in differ-ent HGSOC model systems using newly designed IVT mRNA-based *** introduction of WT p53 mRNA triggered dose-dependent apoptosis,cell cycle arrest,and potent long-lasting inhibition of HGSOC cell *** analysis of OVCAR-8 cells upon mRNA-based p53 reactivation revealed significant alterations in gene expression related to p53 signaling,such as apoptosis,cell cycle regulation,and DNA *** p53 function concurrently reduces chromosomal instability within the HGSOC cells,under-scoring its crucial contribution in safeguarding genomic integrity by moderating the baselin

关键词： apoptosis cell cycle chromosomal instability HGSOC metastatic intraperitoneal mouse model HGSOC orthotopic Xenograft model high-grade serous ovarian cancer in vitro-transcribed p53-mRNA liposomal IVT mRNA delivery system patient-derived organoid patient-derived primary cancer cell