检索结果-南通市图书馆

Journal of Forestry Research 2024年第5期35卷 26-36页

作者： Andrés Baietto Andrés Hirigoyen Jorge hernández Amabelia del Pino Forest Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay National Research Program of Forest Production National Agriculture Research InstituteINIA97000 TacuarembóUruguay soil and Water Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay

Native grasslands in the Pampas of south America are increasingly being replaced by Eucalyptus and Pinus *** short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient *** model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic *** temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by ***;seasonal accumulated precipitation and mean maximum temperature affected litterfall by *** regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for ***(N=33;MAE(mean absolute error)=0.65;RMsE(root mean square error)=0.91;R^(2)=0.71)and ***(N=108;MAE=1.50;RMsE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(***:Ca>N>K>Mg>P;***:N>Ca>K>Mg>P)and micronutrients(*** and ***:Mn>Fe>Zn>Cu)in both *** study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems.

关键词： Afforestation Litterfall Nutrient recycling Climate modeling Myrtaceae Pinaceae

Topical ocular administration of DPP-Ⅳ inhibitors:a new approach for treating diabetes-induced retinal neurodegeneration

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第4期19卷 713-714页

作者： Rafael simó Cristina hernández Diabetes and Metabolism Research Unit Vall d’Hebron Research Institute(VHIR) Department of Medicine Autonomous University of Barcelona Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas(CIBERDEM) Instituto de Salud CarlosⅢ(ICSⅢ)

Retinal neurodegeneration plays a significant role in the pathogenesis of diabetic retinopathy(DR),the leading cause of preventable *** fact,the American Diabetes Association has defined DR as a highly specific neurovascular complication(solomon et al.,2017).Therefore,it is no longer acceptable to consider DR as merely a microvascular *** this regard,the term diabetic retinal disease(DRD)has been proposed as a broader term comprising microangiopathy and ***,there are currently no treatments available that directly target the neurodegenerative changes of *** paper will give new insights into the translational research in this field with particular emphasis on glucagon-like peptide 1/dipeptidyl peptidase IV(GLP-1/DPP-IV)inhibitors.

关键词： neurodegeneration ocular insight

Deep optics preconditioner for modulation-free pyramid wavefront sensing

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2024年第2期12卷 301-312页

作者： FELIPE GUZMÁN JORGE TAPIA CAMILO WEINBERGER nicolás.hernández JORGE BACCA BENOIT NEICHEL EsTEBAN VERA school of Electrical Engineering Pontificia Universidad Católica de Valparaı´soValparaı´soChile Department of systems Engineering Universidad Industrial de SantanderBucaramangaColombia Laboratoire d’Astrophysique de Marseille MarseilleFrance

The pyramid wavefront sensor(PWFs)can provide the sensitivity needed for demanding adaptive optics applications,such as imaging exoplanets using the future extremely large telescopes of over 30 m of diameter(D).However,its exquisite sensitivity has a limited linear range of operation,or dynamic range,although it can be extended through the use of beam modulation—despite sacrificing sensitivity and requiring additional optical *** by artificial intelligence techniques,this work proposes to train an optical layer—comprising a passive diffractive element placed at a conjugated Fourier plane of the pyramid prism—to boost the linear response of the pyramid sensor without the need for cumbersome *** develop an end-2-end simulation to train the diffractive element,which acts as an optical preconditioner to the traditional least-square modal phase estimation *** results with a large range of turbulence conditions show a noticeable improvement in the aberration estimation performance equivalent to over 3λ∕D of modulation when using the optically preconditioned deep PWFs(DPWFs).Experimental results validate the advantages of using the designed optical layer,where the DPWFs can pair the performance of a traditional PWFs with 2λ∕D of *** and adding an optical preconditioner to the PWFs is just the tip of the iceberg,since the proposed deep optics methodology can be used for the design of a completely new generation of wavefront sensors that can better fit the demands of sophisticated adaptive optics applications such as ground-to-space and underwater optical communications and imaging through scattering media.

关键词： process optics pyramid

Attaching CF3 groups to organic molecules using trifluoroacetates via ion-shielding photoelectrocatalysis

在线全文

学校读者我要写书评

暂无评论

science China Chemistry 2024年第11期67卷 3495-3497页

作者： Paula Visiedo-Jiménez Francisco Juliá-hernández Departamento de Química Inorgánica Facultad de Química Universidad de MurciaCampus de Espinardo

Fluorinated molecules play a protagonist role in pharmaceuticals, agrochemicals, and materials. The incorporation of fluoroalkyl groups into organic compounds provides them with unique chemical properties that are key...

关键词：

Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state,Mexico:implication for provenance

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2024年第3期13卷 375-400页

作者： Mayank shukla sanjeet K.Verma Mayla A.Ramos-Vázquez John s.Armstrong-Altrin Karla R.hernández-Martínez sumit Mishra Vivek P.Malviya Héctor hernández-Mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de México Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of Marine sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de Mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and V-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),sierra Madre Oriental(sMOr)and Oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

Learning to bag with a simulation‐free reinforcement learning framework for robots

在线全文

学校读者我要写书评

暂无评论

IET Cyber-systems and Robotics 2024年第2期6卷 52-66页

作者： Francisco Munguia-Galeano Jihong Zhu Juan David hernández Ze Ji Cooper Group University of LiverpoolLiverpoolUK school of Physics Engineering and Technology University of YorkYorkUK school of Computer science and Informatics Cardiff UniversityCardiffUK school of Engineering Cardiff UniversityCardiffUK

Bagging is an essential skill that humans perform in their daily ***,deformable objects,such as bags,are complex for robots to manipulate.A learning-based framework that enables robots to learn bagging is *** novelty of this framework is its ability to learn and perform bagging without relying on *** learning process is accomplished through a reinforcement learning(RL)algorithm introduced and designed to find the best grasping points of the bag based on a set of compact state *** framework utilises a set of primitive actions and represents the task in five *** our experiments,the framework reached 60% and 80% success rates after around 3 h of training in the real world when starting the bagging task from folded and unfolded states,***,the authors test the trained RL model with eight more bags of different sizes to evaluate its generalisability.

关键词： reinforcement learning robot learning robotics

AN OPTIMAL CONTROL PROBLEM FOR A LOTKA-VOLTERRA COMPETITION MODEL WITH CHEMO-REPULsION

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica scientia 2024年第2期44卷 721-751页

作者： Diana I.hernÁndez Diego A.RUEDA-GOMEZ Élder J.VILLAMIZAR-ROA Universidad Industrial de santander Escuela de MatemáticasA.A.678BucaramangaColombia

In this paper we study a bilinear optimal control problem for a diffusive Lotka-Volterra competition model with chemo-repulsion in a bounded domain of ℝ^(ℕ),N=2,*** model describes the competition of two species in which one of them avoid encounters with rivals through a chemo-repulsion *** prove the existence and uniqueness of weak-strong solutions,and then we analyze the existence of a global optimal solution for a related bilinear optimal control problem,where the control is acting on the chemical ***,we derive first-order optimality conditions for local optimal solutions using the Lagrange multipliers ***,we propose a discrete approximation scheme of the optimality system based on the gradient method,which is validated with some computational experiments.

关键词： Lotka-Volterra chemo-repulsion optimal control optimality conditions

Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

在线全文

学校读者我要写书评

暂无评论

Journal of semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán solís-Cisneros Carlos Alberto hernández-Gutiérrez Enrique Campos-González Máximo López-López Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPs)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using sILVACO *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge hernández-Campano sergei A.Kirov Jesús M.hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIs) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

The dark side of cyclooctatetraene(COT):Photophysics in the singlet states of“self-healing”dyes

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第8期35卷 225-228页

作者： supphachok Chanmungkalakul syed Ali Abbas Abedi Federico J.hernández Jianwei Xu Xiaogang Liu Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore Department of Chemistry University College LondonLondon WC1H 0AJUnited Kingdom Institute of sustainability for Chemicals Energy and Environment(ISCE2)Agency for ScienceTechnology and Research(A^(∗)STAR)Jurong Island 627833Singapore

Cyclooctatetraene(COT)attachment to fluorophores(“self-healing”dyes)is known for quenching reac-tive triplet states via triplet-state energy transfer(TET),enhancing ***,COT’s impact on singlet states remains *** calculations reveal that COT induces energy transfer to dark states in deep blue dyes while promoting photoinduced electron transfer(PET)and intersystem crossing(IsC)in visible dyes,potentially compromising brightness and/or *** address this,we pro-pose the use of △E descriptor to optimize COT’s *** findings uncover COT’s multifaceted *** insights will guide the development of superior triplet state quenchers and photostable dyes.

关键词： Cyclooctatetraene Photostability Triplet state quencher Energy transfer Electron transfer