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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

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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

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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

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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

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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

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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01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

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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

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Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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动物营养学报 2024年第1期16卷 422-428页

作者： Edwin T. Moran michael R. Bedford Poultry Science Department Auburn University AL 36830-5416 USA AB Vista Woodstock Court Blenheim Road Marlborough Wiltshire SN8 4AN UK

Phytin is the Ca 2+ -Mg 2+ -K + salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca 2+ . Even at low gastric pH, phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca 2+ near the enzyme's active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide's basic amino acids; coordinating free Ca 2+ , destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca 2+ and other cations re-bind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes (e.g. Ca 2+ , Zn 2+ ) which reduces their structural resistance to autolysis and ability as co-factors (e.g. Zn 2+ ) to increase enzyme activity. Goblet cells initially employ Ca 2+ as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca 2+ is progressively displaced by Na + to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer (USWL). Excessive removal of Ca 2+ from mucin by phytic acid increases its fluidity facilit

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

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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

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A Quasi-Linear Relationship between Planetary Outgoing Longwave Radiation and Surface Temperature in a Radiative-Convective-Transportive Climate Model of a Gray Atmosphere

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Advances in Atmospheric Sciences 2024年第1期41卷 8-18页

作者： Jie SUN michael SECOR Ming CAI Xiaoming HU Department of Earth Oceanand Atmospheric ScienceFlorida State UniversityTallahasseeFlorida 32304USA School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Zhuhai 519082China

In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric poleward energy transport as well as their combined effects for a quasi-linear relationship between the outgoing longwave radiation(OLR)and surface temperature(T_(S)).The greenhouse effect of water vapor enhances the meridional gradient of surface temperature,thereby directly contributing to a quasi-linear OLR-T_(S) *** atmospheric poleward energy transport decreases the meridional gradient of surface *** a result of the poleward energy transport,tropical(high-latitude)atmosphere-surface columns emit less(more)OLR than the solar energy input at their respective locations,causing a substantial reduction of the meridional gradient of the *** combined effect of reducing the meridional gradients of both OLR and surface temperature by the poleward energy transport also contributes to the quasi-linear OLR-T_(S) *** convective energy transport reduces the meridional gradient of surface temperature without affecting the meridional gradient of OLR,thereby suppressing part of the reduction to the increasing rate of OLR with surface temperature by the greenhouse effect of water vapor and poleward energy *** of the nature of the energy balance in the climate system,such a quasi-linear relationship is also a good approximation for the relationship between the annual-mean net downward solar energy flux at the top of the atmosphere and surface temperature.

关键词： outgoing longwave radiation greenhouse effect poleward energy transport

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