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Large-diameter trees dominate snag and surface biomass following reintroduced fire

Ecological Processes 2020年第1期9卷 475-487页

作者： James A.Lutz soren struckman Tucker J.Furniss C.Alina Cansler sara J.Germain Larissa *** Darren J.mcAvoy Crystal A.Kolden alistair m.s.smith mark E.swanson Andrew J.Larson Department of Wildland Resources S.J.and Jessie E.Quinney College of Natural ResourcesUtah State University5230 Old Main HillLoganUtah 84322-5230USA school of Environmental and Forest sciences University of WashingtonBox 352100SeattleWashington 98195USA management of Complex systems University of CaliforniaMerced5200 North Lake RoadMercedCalifornia 95343USA Department of Forest Rangelandand Fire SciencesCollege of Natural ResourcesUniversity of Idaho875 Perimeter DriveMoscowIdaho 83844-1133USA school of the Environment Washington State UniversityBox 646410PullmanWashington 99164-6420USA Wilderness Institute W.A.Franke College of Forestry and ConservationUniversity of Montana32 Campus DriveMissoulaMontana 59812USA

The reintroduction of fire to landscapes where it was once common is considered a priority to restore historical forest dynamics,including reducing tree density and decreasing levels of woody biomass on the forest ***,reintroducing fire causes tree mortality that can have unintended ecological outcomes related to woody biomass,with potential impacts to fuel accumulation,carbon sequestration,subsequent fire severity,and forest *** this study,we examine the interplay between fire and carbon dynamics by asking how reintroduced fire impacts fuel accumulation,carbon sequestration,and subsequent fire severity *** pre-fire,and continuing 6 years post-fire,we tracked all live,dead,and fallen trees≥1 cm in diameter and mapped all pieces of deadwood(downed woody debris)originating from tree boles≥10 cm diameter and≥1 m in length in 25.6 ha of an Abies concolor/Pinus lambertiana forest in the central sierra Nevada,California,*** also tracked surface fuels along 2240 m of planar transects pre-fire,immediately post-fire,and 6 years *** years after moderate-severity fire,deadwood≥10 cm diameter was 73 mg ha^(−1),comprised of 32 mg ha^(−1) that persisted through fire and 41 mg ha^(−1) of newly fallen wood(compared to 72 mg ha^(−1) pre-fire).Woody surface fuel loading was spatially heterogeneous,with mass varying almost four orders of magnitude at the scale of 20 m×20 m quadrats(minimum,0.1 mg ha^(−1);mean,73 mg ha^(−1);maximum,497 mg ha^(−1)).Wood from large-diameter trees(≥60 cm diameter)comprised 57%of surface fuel in 2019,but was 75%of snag biomass,indicating high contributions to current and future fuel *** of fire does not consume all large-diameter fuel and generates high levels of surface fuels≥10 cm diameter within 6 *** fires are needed to reduce surface fuel loading.

关键词： California Rim Fire Fuel reduction sierra Nevada mixed-conifer smithsonian ForestGEO Yosemite Forest Dynamics Plot Yosemite National Park

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Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger samantha J.Holdsworth alistair J.Gunn Laura Bennet Hamid Abbasi mātai medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

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methane and nitrous oxide emissions from a subtropical coastal embayment(moreton Bay, Australia)

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Journal of Environmental sciences 2015年第3期27卷 82-96页

作者： Ronald s.musenze Ursula Werner alistair Grinham James Udy Zhiguo Yuan Advanced Water management Centre (AWmC) The University of Queensland Department of Civil and Environmental Engineering College of Engineering Design Arts and Technology Makerere University school of Civil Engineering The University of Queensland Healthy Waterways Ltd.

surface water methane （CH4） and nitrous oxide （N20） concentrations and fluxes were investigated in two subtropical coastal embayments （Bramble Bay and Deception Bay, which are part of the greater moreton Bay, Australia）. measurements were done at 23 stations in seven campaigns covering different seasons during 2010-2012. Water-air fluxes were estimated using the Thin Boundary Layer approach with a combination of wind and currents-based models for the estimation of the gas transfer velocities. The two bays were strong sources of both CH4 and N2O with no significant differences in the degree of saturation of both gases between them during all measurement campaigns. Both CH4 and N2O concentrations had strong temporal but minimal spatial variability in both bays. During the seven seasons, CH4 varied between 500% and 4000% saturation while N2O varied between 128 and 255% in the two bays. Average seasonal CH4 fluxes for the two bays varied between 0.5 ± 0.2 and 6.0 ± 1.5 mg CH4/（m^***） while N20 varied between 0.4 ± 0.1 and 1.6 ± 0.6 mg N2O/（m^2-day）. Weighted emissions （t CO2-e） were 63%-90% N2O dominated implying that a reduction in N2O inputs and/or nitrogen availability in the bays may significantly reduce the bays＇ greenhouse gas （GHG） budget. Emissions data for tropical and subtropical systems is still scarce. This work found subtropical bays to be significant aquatic sources of both CH4 and N2O and puts the estimated fluxes into the global context with measurements done from other climatic regions.

关键词： Greenhouse gas emissions subtropical aquatic systems Bay methane Nitrous oxide Uncertainty

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Diabetic retinopathy: recent advances towards understanding neurodegeneration and vision loss

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science China(Life sciences) 2015年第6期58卷 541-549页

作者： BARBER alistair J. Penn state Hershey Eye Center Penn State Hershey College of Medicine Milton S. Hershey Medical Center

Diabetic retinopathy （DR） is one of the most common retinal diseases world-wide. It has a complex pathology that involves the vasculature of the inner retina and breakdown of the blood-retinal barrier. Extensive research has determined that DR is not only a vascular disease but also has a neurodegenerative component and that essentially all types of ceils in the retina are affected, leading to chronic loss of visual function. A great deal of work using animal models of DR has established the loss of neurons and pathology of other cell types, including supporting glial cells. There has also been an increased emphasis on measuring retinal function in the models, as well as further validation and extension of the animal studies by clinical and translational research. This article will attempt to summarize the more recent developments in research towards understanding the complexities of retinal neurodegeneration and functional vision loss in DR.

关键词： retina diabetes neurodegeneration visual function vascular function apoptosis synapse dendrite

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Quality of life assessment in patients with chronic pancreatitis receiving antioxidant therapy

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World Journal of Gastroenterology 2010年第32期16卷 4066-4071页

作者： Nehal s shah alistair J makin Aali J sheen Ajith K siriwardena Hepatobiliary surgery Unit Manchester Royal InfirmaryManchester M13 9WLUnited Kingdom Department of Gastroenterology Manchester Royal InfirmaryManchester M13 9WLUnited Kingdom

AIm:To undertake a baseline study comparing quality of life(QoL) in patients with chronic pancreatitis(CP) on Antox to those with CP,matched for disease duration,who were not on this ***:CP was defined according to the Zurich *** eight consecutive patients with CP who were taking Antox(antioxidants) were compared with 69 consecutive control CP patients not on *** Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core questions 30 and Pancreatic modification(28 questions) were used to assess *** of a total of 137 patients 28 in each group were matched for disease duration(within 12 mo).median disease duration was 8(1-22) years in the Antox group and 7(1-23) years in the Non-Antox cohort(P = Ns,mann-Whitney U-test).Other parameters(age,gender,etiology,endocrine and exocrine insufficiency) were similar between ***:median visual analogue pain score in the Antox group was 3(0-8) compared with 6(0-8) in the Non-Antox group(P s of cognitive,emotional,social,physical and role function were impaired in the Non-Antox group compared to Antox patients(P spectively).Analgesics and opiate usage was significantly lower in the Antox group(P sical health and global QoL was better in the Antox group(P sION:Contemporary quality of life assessments show that after correction for disease duration and cigarette smoking,patients with CP taking antox had better scores than non-antox controls.

关键词： Chronic pancreatitis Antioxidants Quality of life Assessment management

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Tracer advection in an idealised river bend with groynes

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Journal of Hydrodynamics 2018年第5期30卷 780-790页

作者： mohammad mahdi Jalali alistair G.L.Borthwick Institute for Energy systems School of Engineering The University of Edinburgh

This paper presents numerical simulations of particle advection in the bend of an open channel containing groynes, which is an idealised form of a shallow river bend in a wide river. The flow field is computed using a boundary-fitted solver of the non-orthogonal, curvilinear shallow water equations. The computational grid is generated by solving Poisson-type elliptic partial differential equations using an iterative multi-grid scheme for prescribed boundary coordinates. The shallow water equations are discretised with finite differences in space, and 4 t h order Runge-Kutta integration in time. Tracers introduced at specific initial locations have their trajectories computed using Lagrangian particle tracking. The numerical shallow flow model is verified by comparison to the analytical solution of fully developed flow in an open channel. The combined shallow flow and Lagrangian particle-tracking model is then used to simulate the advection of tracer particles in a rectangular channel containing a pair of parallel groynes, and tracer particles in a curved open channel containing groynes, of dimensions roughly equivalent to a Danube River bend.

关键词： shallow water equations tracer advection Lagrangian particle curvilinear coordinates system river bend groynes

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Tracer advection in a pair of adjacent side-wall cavities, and in a rectangular channel containing two groynes in series

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Journal of Hydrodynamics 2018年第4期30卷 564-572页

作者： mohammad mahdi Jalali alistair G.L.Borthwick Institute for Energy systems School of Engineering The University of Edinburgh

A model is presented of particle advection near groynes in an open channel. Open channel hydrodynamics is modelled using the shallow water equations, obtained as the depth-averaged form of Reynolds-averaged continuity and Navier-stokes momentum equations. A Lagrangian particle-tracking model is used to predict trajectories of tracer particles advected by the flow field, with bilinear interpolation representing the continuous flow field. The particle-tracking model is verified for chaotic advection in an alternating flow field of a pair of blinking vortices. The combined shallow flow and Lagrangian particle-tracking model is applied to the simulation of tracer advection in flow past a pair of side-wall cavities separated by a groyne, and in an open rectangular channel containing a pair of parallel groynes oriented normal to the channel wall. The study is potentially useful in understanding mixing processes in shallow flow fields near hydraulic structures in wide rivers.

关键词： shallow water equations Lagrangian particle tracking chaotic advection blinking vortices side-wall cavities groynes

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Paleobiological significance of the James Ross Basin

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Advances in Polar science 2019年第3期30卷 186-198页

作者： J.alistair CRAmE British Antarctic survey High CrossMadingley RoadCambridge CB3 0ETUK

The extensive Late mesozoic–Early Cenozoic sedimentary succession exposed within the James Ross Basin,Antarctica has huge potential to enhance paleobiological investigations into both the marine and terrestrial fossil *** excess of 7 km in total thickness and spanning the Early Cretaceous(Aptian)–Late Eocene in age,it represents an invaluable high-latitude(~65°s)site for comparison with lower latitude,tropical ones in an essentially greenhouse *** Early Cretaceous(Aptian–Albian)sequence is deep-water but there are indications of shallowing to inner shelf depths in both the Turonian and Coniacian *** first prolific shallow-water marine fauna occurs in the santonian–Campanian santa marta Formation and this is followed by repeated occurrences through the later Campanian,maastrichtian,Danian and middle Eocene(Lutetian).In this study an attempt has been made to compare these Antarctic faunas directly with the well-known ones of the same age from the Us Gulf *** comparisons made for three time slices,Late maastrichtian,Danian and middle Eocene,indicate that the Antarctic is characterised by both low taxonomic diversity and high levels of *** James Ross Basin is providing important evidence to indicate that the highest southern latitudes have always been characterised by a distinctive temperate biota,even on a pre-glacial *** roots of at least some elements of the modern southern Ocean biota can be traced back to a Late mesozoic–Early Cenozoic austral realm.

关键词： James Ross Basin biostratigraphy molluscan faunas Us Gulf Coast biodiversity patterns evolutionof temperate biotas

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Does mgsO_(4) protect the preterm brain?Dissecting its role in the pathophysiology of hypoxic ischemic encephalopathy

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Neural Regeneration Research 2024年第9期19卷 1861-1862页

作者： Robert Galinsky Laura Bennet alistair J.Gunn The Ritchie Centre Hudson Institute of Medical ResearchMelbourneVICAustralia Department of Obstetrics and Gynaecology Monash UniversityMelbourneVICAustralia Department of Physiology The University of AucklandAucklandNew Zealand

mitigating preterm encephalopathy continues to be one of the greatest challenges in perinatal *** encephalopathy is associated with high mortality,serious morbidity,and significant socio-economic impacts on the individuals,their families,and public health sectors and welfare systems that last a *** cost of disability associated with preterm brain injury continues to *** of this injury,and disability,would significantly reduce this socioeconomic burden.

关键词： encephalopathy mortality hypoxic

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A geocomputational analysis of Twitter activity around different world cities

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Geo-spatial Information science 2014年第3期17卷 145-152页

作者： muhammad ADNAN alistair LEAK Paul LONGLEY Department of Geography University College LondonGower StreetLondon WC1E 6BTUK Department of security and Crime science University College London35 Tavistock SquareLondon WC1H 9EZUK

The penetration and use of social media services differs from city to *** paper is aimed to provide a comparison of the use of Twitter between different cities of the *** present a temporal analysis of activity on Twitter in 15 *** study consists of two parts:First,we created temporal graphs of the activity in the 15 cities,through which hours of high and low activity could be ***,we created heat map visualizations of the Twitter activities during the period of 19 september 2012–25 september *** heat map visualizations make the periods of intense and sparse activity apparent and provide a snapshot of the activity during the whole year.

关键词： Twitter temporal analysis heat map visualization activity patterns

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