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A new method of calculating crown projection area and its comparative accuracy with conventional calculations for asymmetric tree crowns

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Journal of Forestry Research 2024年第4期35卷 171-188页

作者： Mingrui Zhang Huiquan Bi Xingji Jin michael McLean School of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Forest Science NSW Department of Primary IndustriesLevel 304PSQ12 Darcy StreetParramattaNSW 2150Australia School of Ecosystem and Forest Sciences The University of MelbourneMelbourne 3010Australia

This paper introduces a new method of calculating crown projection area(CPA),the area of level ground covered by a vertical projection of a tree crown from measured crown radii through numerical interpolation and *** novel method and other four existing methods of calculating CPA were compared using detailed crown radius measurements from 30 tall trees of Eucalyptus pilularis variable in crown size,shape,and *** four existing methods included the polygonal approach and three ways of calculating CPA as the area of a circle using the arithmetic,geometric and quadratic mean *** were made across a sequence of eight non-consecutive numbers(from 2 to 16)of measured crown radii for each tree over the range of crown asymmetry of the 30 trees through generalized linear models and multiple comparisons of *** sequence covered the range of the number of crown radii measured for calculating the CPA of a tree in the literature.A crown asymmetry index within the unit interval was calculated for each tree to serve as a normative *** a slight overestimation of 2.2%on average and an overall mean error size of 7.9%across the numbers of crown radii that were compared,our new method was the least biased and most *** CPA as a circle using the quadratic mean crown radius was the second best,which had an average overestimation of 4.5%and overall mean error size of 8.8%.These two methods remained by and large unbiased as crown asymmetry increased,while the other three methods showed larger bias of *** the conventional method of using the arithmetic mean crown radius to calculate CPA as a circle,bias correction factors were developed as a function of crown asymmetry index to delineate the increasing magnitude of bias associated with greater degrees of crown *** study reveals and demonstrates such relationships between the accuracy of CPA calculations and crown asymmetry and will help increase awa

关键词： Crown radius measurements Interpolated crown contour Projected crown area Multiple comparisons of means

Benign stricture of bilioenteric anastomosis after Whipple withsynthetic polypropylene suture

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 103-105页

作者： A michael Devane Christine MG Schammel Department of Radiology Prisma Health UpstateGreenvilleUSA Department of Pathology Prisma Health UpstateGreenvilleUSA

To the Editor:Biliary stricture formation at the bilioenteric anastomosis is an infrequent complication(2%-3%)after pancreaticoduodenectomy;the average presentation is within 13-14 months(range from 1 month to 9 years)after surgery[1,2].While the etiology is unknown,development of biliary stricture has shown to be more likely if a bile leak occurs in the postoperative period[3,4]and with younger patients[5].

关键词： stricture anastomosis Whipple

Mesenchymal stem cell-derived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration

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Neural Regeneration Research 2024年第1期19卷 49-54页

作者： Ye Xiong Asim Mahmood michael Chopp Department of Neurosurgery Henry Ford HospitalDetroitMIUSA Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA

Traumatic brain injury is a serious and complex neurological condition that affects millions of people *** significant advancements in the field of medicine,effective treatments for traumatic brain injury remain ***,extracellular vesicles released from mesenchymal stem/stromal cells have emerged as a promising novel therapy for traumatic brain *** vesicles are small membrane-bound vesicles that are naturally released by cells,including those in the brain,and can be engineered to contain therapeutic cargo,such as anti-inflammatory molecules,growth factors,and *** administered intravenously,extra cellular vesicles can cross the blood-brain barrier and deliver their cargos to the site of injury,where they can be taken up by recipient cells and modulate the inflammatory response,promote neuroregeneration,and improve functional *** preclinical studies,extracellular vesicle-based therapies have shown promising results in promoting recove ry after traumatic brain injury,including reducing neuronal damage,improving cognitive function,and enhancing motor *** further research is needed to establish the safety and efficacy of extra cellular vesicle-based therapies in humans,extra cellular vesicles represent a promising novel approach for the treatment of traumatic brain *** this review,we summarize mesenchymal ste m/stromal cell-de rived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration and brainderived extracellular vesicles as potential biofluid biomarkers in small and large animal models of traumatic brain injury.

关键词： biomarkers extracellular vesicles functional outcome mesenchymal stem/stromal cells neuroinflammation neuroplasticity neuroprotection traumatic brain injury

Iterative Subregion Correction Preconditioners with Adaptive Tolerance for Problems with Geometrically Localized Stiffness

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Communications on Applied Mathematics and Computation 2024年第2期6卷 811-836页

作者： michael Franco Per-Olof Persson Will Pazner Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720-3840USA Fariborz Maseeh Department of Mathematics and Statistics Portland State UniversityPortlandOR 97201USA

We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated *** preconditioners are designed to treat the case of geometrically localized stiffness,where the convergence rates of iterative methods are degraded in a localized subregion of the *** convergence may be caused by a number of factors,including the mesh size,anisotropy,highly variable coefficients,and more challenging *** approach taken in this work is to correct well-known preconditioners such as the block Jacobi and the block incomplete LU(ILU)with an adaptive inner subregion *** goal of these preconditioners is to reduce the number of costly global iterations by accelerating the convergence in the stiff region by iterating on the less expensive reduced *** tolerance for the inner iteration is adaptively chosen to minimize subregion-local work while guaranteeing global convergence *** present analysis showing that the convergence of these preconditioners,even when combined with an adaptively selected tolerance,is independent of discretization parameters(e.g.,the mesh size and diffusion coefficient)in the *** demonstrate significant performance improvements over black-box preconditioners when applied to several model convection-diffusion ***,we present performance results of several variations of iterative subregion correction preconditioners applied to the Reynolds number 2.25×10^(6)fluid flow over the NACA 0012 airfoil,as well as massively separated flow at 30°angle of attack.

关键词： Subregion correction Nested Krylov Geometrically localized stiffness

Emerging glacier forelands alter carbon dynamics on the Tibetan Plateau

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Journal of Mountain Science 2024年第9期21卷 2871-2875页

作者： GAO Tanguang ZHANG Yulan MEADOWS michael Edward College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geography and Ocean Sciences Nanjing UniversityNanjing 210023China Department of Environmental&Geographical Science University of Cape TownRondebosch 7701South Africa

The critical challenge of ongoing climate warming is resulting in glacier melting globally,a process accompanied by the formation of substantial glacier *** phenomenon emerges as a pivotal area of study,especially in the Tibetan Plateau(TP),known as the Third Pole and the Asian Water *** particular,the rapid retreat of temperate glaciers in the southeastern TP has led to the formation of expansive glacier *** forelands are not merely evidence of climate shifts but are also key areas for transformative carbon ***,the newly exposed land surface actively adjusts the balance of dissolved organic carbon,especially in meltwater,and influences the release of greenhouse gases from a range of sources including glacial lakes,subglacial sediments,and supraglacial/proglacial *** processes play a crucial role in the dynamics of atmospheric carbon *** from our intensive and detailed observations over several years,this perspective not only emphasizes the importance of the underexplored impact of glacier forelands on carbon cycles but also opens a window into understanding potential future trajectories in a warming world.

关键词： Glacier Climate warming Carbon release Tibetan Plateau

Harnessing naturally occurring mutations for T-cell therapy:a potential new avenue to enhance treatment efficacy

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1799-1801页

作者： michael Hiltensperger Jürgen Ruland Kilian Schober Mikrobiologisches Institut-Klinische Mikrobiologie Immunologie und HygieneFriedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany Institute of Clinical Chemistry and Pathobiochemistry School of MedicineTechnical University of MunichMunichGermany TranslaTUM Center for Translational Cancer ResearchTechnical University of MunichMunichGermany German Cancer Consortium(DKTK) HeidelbergGermany German Center for Infection Research(DZIF) partner site MunichMunichGermany FAU Profile Center Immunomedicine Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

In a recent study published in Nature,Garcia et *** a sophisticated approach to identify fitness-enhancing mutations for T cells that was inspired by cancer evolution.1 The identified CARD11-PIK3R3 gene fusion enhanced tumor rejection and persistence of engineered T cells in multiple tumor models and might have the potential to improve efficacy of adoptive T-cell therapies in cancer patients.

关键词： cancer potential

Stability and Generalization of Hypergraph Collaborative Networks

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Machine Intelligence Research 2024年第1期21卷 184-196页

作者： michael K.Ng Hanrui Wu Andy Yip Institute of Data Science The University of Hong KongHong KongChina Department of Mathematics The University of Hong KongHong KongChina College of Information Science and Technology Jinan UniversityGuangzhou 510006China

Graph neural networks have been shown to be very effective in utilizing pairwise relationships across ***,there have been several successful proposals to generalize graph neural networks to hypergraph neural networks to exploit more com-plex *** particular,the hypergraph collaborative networks yield superior results compared to other hypergraph neural net-works for various semi-supervised learning *** collaborative network can provide high quality vertex embeddings and hyperedge embeddings together by formulating them as a joint optimization problem and by using their consistency in reconstructing the given *** this paper,we aim to establish the algorithmic stability of the core layer of the collaborative network and provide generaliz--ation *** analysis sheds light on the design of hypergraph filters in collaborative networks,for instance,how the data and hypergraph filters should be scaled to achieve uniform stability of the learning *** experimental results on real-world datasets are presented to illustrate the theory.

关键词： Hypergraphs vertices hyperedges collaborative networks graph convolutional neural networks(CNNs) stability generalization guarantees

Water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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Ecological Processes 2024年第1期13卷 217-236页

作者： Matthew L.Skoog michael A.Eggleton Yushun Chen Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota Department of Natural Resources State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P < 0.001–0.010). Differences between agriculture and forest streams with respect to other physical and chemical variables were intermittent and season dependent. Fish assemblages in agriculture and forest streams were structured primarily along an environmental gradient reflecting instream habitat conditions, water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream Land use Water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain

Resident immune responses to spinal cord injury:role of astrocytes and microglia

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Neural Regeneration Research 2024年第8期19卷 1678-1685页

作者： Sydney Brockie Cindy Zhou michael G.Fehlings Division of Genetics and Development Krembil Research InstituteUniversity Health NetworkTorontoONCanada Institute of Medical Science University of TorontoTorontoONCanada Division of Neurosurgery and Spine Program Department of SurgeryUniversity of TorontoTorontoONCanada

Spinal cord injury can be traumatic or non-traumatic in origin,with the latter rising in incidence and prevalence with the aging demographics of our *** r,as the global population ages,individuals with co-existent degenerative spinal pathology comprise a growing number of traumatic spinal cord injury cases,especially involving the cervical spinal *** makes recovery and treatment approaches particula rly challenging as age and comorbidities may limit regenerative *** these reasons,it is critical to better understand the complex milieu of spinal cord injury lesion pathobiology and the ensuing inflammatory *** review discusses microglia-specific purinergic and cytokine signaling pathways,as well as microglial modulation of synaptic stability and plasticity after ***,we evaluate the role of astrocytes in neurotransmission and calcium signaling,as well as their border-forming response to neural *** the inflammatory and reparative roles of these cells have eluded our complete understanding and remain key therapeutic targets due to their extensive structural and functional roles in the nervous *** advances have shed light on the roles of glia in neurotransmission and reparative injury responses that will change how interventions are *** key processes and existing knowledge gaps will allow future research to effectively target these cells and harness their regenerative potential.

关键词： astrocytes glial signaling microglia spinal cord injury synaptic transmission