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Leading directions and effective distance of larch offspring dispersal at the upper treeline in the Northern and Polar Urals, Russia

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Forest Ecosystems 2024年第5期11卷 603-617页

作者： P.A.Moiseev V.L.Semerikov T.V.Semerikova D.S.Balakin i.B.Voro.i.v S.o.Viuykhin institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesEkaterinburg620144Russia Center for Genetics and Life Science Sirius University of Science and Technology354340SochiRussia

Climate has changed sufficiently over the last 150 years and forced out upper treeline advance at the most studied sites around the *** rate of advance has been extremely variable–from tens to hundreds meters in *** is because the degree at which tree frontal populations respond to climate change depends on the complex interaction of biolo.i.al and physical *** resulting stand pattern is the consequence of the interaction between dispersal and survival functions.A few publications have addressed the question of how this pattern is *** order to understand how the spatial structure of tree stands was formed at the upper limit of their distribution in the Ural Mountains,we assessed the distance and direction of dispersal of offspring from maternal *** found that in frontal Larix sibirica ***,‘effective’dispersal of offspring ranges from 3 to 758 m(with a median of 20–33 m in open forest and 219 m in single-tree tundra in the Polar Urals and 107 m in open forest in the Northern Urals).We revealed that most of the offspring effectively dispersed not only in the direction of the prevailing winds,but also.i. the oppo.i.e direction up the slope,and the distance can reach 500–760 *** data obtained can be used to develop an individual-based model which is capable of simulating in detail the dynamics of tree stands at the upper limit of their growth and reliably predicting the future po.i.ion and pattern of treeline ecotone as growth conditions continue to.i.prove in the face of observed climate change.

关键词： Effective dispersal distance Upper treeline Parentage analysis Age estimation Terrestrial laser scanning Larix sibirica Ural mountains

The current status and future development of high-temperature conventional superconductivity

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National Science Review 2024年第7期11卷 18-20页

作者： Mikhail i.Eremets High Pressure Chemistry and Physics Group Max-Planck-Institut für Chemie

This survey highlights key advancements in high-temperature superconductivity in hydrogen-rich materials, emphasizing the robust evidence and reproducibility of superconductivity under challenging experimental conditions of megabar pressures. in the near future, achieving room-temperature superconductivity is highly probable, and the field is expected to transition towards near-ambient-pressure superconductivity.

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Using fracture-based continuum modeling of coupled geomechanical-hydrolo.i.al processes for numerical simulation of hydraulic fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1582-1599页

作者： Goodluck i.ofoegbu GNo Modeling Research LLC. San AntonioTX78253USA

This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrolo.i.al processes to evaluate a technique for high-density fracturing and fracture *** simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(*** re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain *** simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density *** combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing *** are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tenso.i.l aggregation of the behavior of discrete fractures and unfractured *** are presented for previously unfractured rock and for rock with preexisting fractures of ho.i.ontal,shallow-dipping,steeply dipping,or vertical *** of a single-well model are used to determine the pattern and spacing for a multiple-well *** results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or ho.i.ontal fractures,and in situ vertical compressive stress greater than *** preexisting fractures are steeply dipping or vertical,and considering the same in situ

关键词： Discrete fracture Fracture-based continuum modeling Fracture caging High-density fracturing Hydraulic fracturing Preexisting fracture

Making topolo.i.al protein links using enzymatic reactions

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National Science Review 2024年第3期11卷 50-51页

作者： Roger Castells-Graells Todd o.Yeates Department of Chemistry and Biochemistry University of California UCLA-DoE institute for Geno.i.s and Proteo.i.s

Proteins are exceedingly complex molecules though, at their heart, they are essentially linear polymers. Pull at their ends and one obtains an extended backbone. While that is true in most cases, some natural proteins... 详细信息

关键词： DESiGN

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David i.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGRoTECNio-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSiRo Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain iuFoR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. in this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the po.i.ion and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when gro.i.g conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction interspecific competition intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

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A synthetic micro.i.l community used as a bioinoculant can overcome rice production constraints in acid soils

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Science China(Life Sciences) 2024年第5期67卷 1085-1086页

作者： Maureen o’Callaghan Shengjing Shi Resilient Agriculture Group AgResearchLincolnChristcurch 8140New Zealand

A custo.i.ed synthetic micro.i.l community(SynCom)composed of carefully selected rhizosphere-competent bacterial strains improved rice growth,yield and resistance to soil acidity and Al to.i.ity.

关键词： soil soils rhizosphere

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Valo.i.ation of Tree Bark-Derived Suberin in Applications for the Bio-Based Compo.i.es industry–A Recent Review

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Journal of Renewable Materials 2024年第6期12卷 1029-1042页

作者： Aleksandra Jeżo institute of Wood Sciences and Furniture SGGWNowoursynowska St.159Warsaw02-776Poland

Bark extracts are sustainable sources of biopolymers and hold great pro.i.e for replacing fossil fuel-based polymers,for example,in wood-based *** addition to primary and secondary metabo.i.es,tree bark also contains suberin,which plays a major role in protecting the tree from environmental *** is a natural aliphatic-aromatic cross-linked polyester present in the cell walls of both normal and damaged external tissues,the main component of which are long-chain aliphatic *** main role as a plant ingredient is to protect against micro.i.lo.i.al factors and water *** of the most important suberin monomers are suberin fatty acids,known for their hydropho.i. and barrier ***,due to the diverse chemical compo.i.ion of suberin,it is an attractive alternative to hydrocarbon-based *** its potential is recognized,it is not widely used in biocompo.i.es technology,including wood-based compo.i.es and the polymer *** article will discuss the current knowledge about the potential of suberin and its components in biocompo.i.es technology,which will include surface finishes,compo.i.e adhesives and polymer blends.

关键词： Suberin suberinic acids wood compo.i.es biocompo.i.es biopolyester

Congenital Mesoblastic Nephroma: A Case Report

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open Journal of Pediatrics 2024年第5期14卷 834-840页

作者： E. A. Alinnor o. C. Ugwa i. o. Nnamani Department of Paediatrics University of Port Harcourt Teaching Hospital Port Harcourt Nigeria Department of Anato.i.al Pathology University of Port Harcourt Teaching Hospital Port Harcourt Nigeria

Background: Congenital Mesoblastic Nephroma (CMN) is a mesenchymal renal tumour of early life. With a median diagno.i. of two months and over 90% of cases occurring within the first year of life, it is the most prevalent non-Wilms’ renal tumour. Even though imaging can be used as a diagno.i.g tool, it is frequently identified in the neonatal period when the baby has an abdo.i.al mass. There are three different histolo.i. types: mixed, cellular, and classic. Radical nephrectomy is the usual mode of treatment, though adjuvant chemotherapy may be necessary for the cellular type, which may be aggressive. Case presentation: We report on a case of a 2-day-old term male neonate born to a 27-year-old mother through spontaneous vertex delivery (SVD). He presented with a right-sided abdo.i.al mass from birth. An abdo.i.al ultrasound scan revealed a huge, well-circumscribed heterogeneous soft tissue mass in the right hemi-abdomen extending to the left side, measuring 10.2 cm by 8.0 cm. He underwent a right radical nephrectomy with a tumour weight of 450 g and a size of 18 cm × 15 cm × 6 cm. Histopatholo.i.al diagno.i. was Congenital Mesoblastic Nephroma (cellular type) Stage 1. Conclusion: Any infant with a renal tumour should be evaluated for congenital mesoblastic nephroma. Detailed investigation and complete resection are fundamental for ensuring an excellent outcome.

关键词： Congenital Mesoblastic Nephroma Nephrectomy Neonate

Rotating effects on the photoio.i.ation cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： Carlos Magno o Pereira Frankbelson dos S Azevedo Luís Fernando C Pereira Edilberto o Silva Departamento de Física Universidade Federal do Maranh?o

in this article, we investigate the nonrelativistic quantum mo.i.n of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. our analysis entails the derivation of the equation of mo.i.n and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, pro.i.ing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoio.i.ation cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoio.i.ation process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoio.i.ation cross-section quantum ring rotating effect