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Effect of pipe installation and external load on buried steel pipe responses:Experimental and numerical investigations

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Underground Space 2024年第2期15卷 44-58页

作者： Yadong Zhang ron Chik-Kwong Wong Jianfeng Chen Wei Su Department of Civil Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

During pipe installation,compacting soil at pipe sides causes an initial pipe deformation which is known as the"peaking"***,in conventional pipe design codes,only pipe deformation caused by vertical overburden is considered while the"peaking"effect is *** this study,a full-scale test was conducted on a Grade X52 steel pipe with a diameter of 600 mm to investigate the impacts of both soil compaction and vertical overburden on pipe *** compaction and external load were found to elongate and shorten the vertical pipe diameter,***"peaking"effect was observed during the installation procedure accompanied by the highest pipe stress measured at the pipe ***,a two-dimensional finite element model was created and validated based on the calculated pipe stresses from the experimental study.A parametric study was performed thereafter to numerically study the impacts of soil water content,pipe wall thickness,compaction pressure,and lift thickness on pipe responses due to soil compaction and external *** increase in the"peaking"effect is observed with increasing soil water content and compaction pressure,while an increase in pipe wall thickness or lift thickness would cause a decrease in the"peaking"effect.

关键词： X52 steel Soil compaction External load peaking effect Pipe deflection Soil arching

Small molecules to target tau amyloid aggregation

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Neural Regeneration Research 2024年第3期19卷 509-511页

作者： Zoe Manglano-Artuñedo Samuel peña-Díaz Salvador Ventura Institut de Biotecnologia i Biomedicina Universitat Autònoma de BarcelonaBellaterraSpain

Protein aggregation has been linked with many neurodegenerative diseases,such as Alzheimer’s disease(AD)or Parkinson’s *** belongs to a group of heterogeneous and incurable neurodegenerative disorders collectively known as *** comprise frontotemporal dementia,Pick’s disease,or corticobasal degeneration,among *** symptomatology varies with the specific tau protein variant involved and the affected brain region or cell ***,they share a common neuropathological hallmark-the formation of proteinaceous deposits named neurofibrillary *** tangles,primarily composed of aggregated tau(Zhang et al.,2022),disrupt normal neuronal functions,leading to cell death and cognitive decline.

关键词： tau degeneration aggregation

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 scheme. 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 scheme.

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1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. Researchers 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 f = 96.08, p f cones produced in a given year. These annual fluctuations in seed production are determining factors in the population dynamics of forest species. 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

Porphyrins,phthalocyanines,and related covalent-organic frameworks in the photochemical and electrochemical 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 Chemistry 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 photochemical and electrochemical water splitting(WS)using porphyrins,phthalocyanines,related macrocycles,and their metal complexes are *** efforts are being carried out in order to develop novel and cheap 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 sonochemical 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 Chemistry 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,electrochemical 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,chemical 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 Kangchenjunga 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

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN M.MOHAMMADIMEHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

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