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Eight decades of compositional change in a managed northern hardwood landscape

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Forest Ecosystems 2023年第3期10卷 398-410页

作者： mark J.Ducey Olivia L.Fraser Mariko Yamasaki Ethan P.belair William b.Leak University of New Hampshire Department of Natural Resources and the Environment114 James HallDurhamNH03824USA U.S.D.A.Forest Service White Mountain National Forest71 White Mountain DriveCamptonNH03223USA U.S.D.A.Forest Service Northern Research Station271 Mast RoadDurhamNH03824USA The Nature Conservancy Natural Climate SolutionsAfrica Regional Portland Office45 Exchange StSuite 303PortlandME04101USA

We analyzed over 8 decades of change in forest composition(represented by species proportion of basal area)and size class from more than 400 permanent plots located on the bartlett Experimental Forest in the White Mountains of New *** data represent one of the longest-term landscape-scale records of forest change based on permanent plots in North *** analyzed the plots based on elevation class,land type indicating assumed successional direction(grouped into coniferous and deciduous),and inventory period within managed and unmanaged portions of the *** ongoing shift from small-to large-diameter stems is clear across all species,in response to the overall aging of the forest following exploitative harvesting in the 19th *** compositional changes include a continuing decline in shade-intolerant species(paper birch and aspen),along with the mid-tolerant yellow *** increase in red maple abundance through the early 1990s has leveled off or *** shade-tolerant species,increases in beech and red spruce were largely consistent with assumed land type on unmanaged plots,but heavy marking against diseased beech on managed plots restricted increase of that *** maple declined in abundance except where silvicultural intervention helped maintain *** contrast,eastern hemlock showed a continuing expansion at all elevations below 600 *** data continue to show little or no evidence of upward migration of species,despite evidence of recent regional change in ***,the bEF is poised for substantial changes when emerald ash borer and hemlock woolly adelgid,both of which are known to infest nearby areas,do arrive.

关键词： Northern hardwoods Succession Stand dynamics Silviculture

Atmospheric deposition of 7be,210Pb and 210Po during typhoons and thunderstorm in Shanghai, China and global data synthesis

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Science China Earth Sciences 2020年第4期63卷 602-614页

作者： Juan DU mark bASKARAN Jinzhou DU State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China Department of Geology Wayne State UniversityDetroit 48202USA

Atmospherically-delivered ~7be,^(210)Po and ^(210)Pb in bulk precipitation and air samples collected around the globe have provided valuable quantification on the rates of removal, as well as proportional mixing of attendant air masses;however, such studies during thunderstorm and typhoon events are limited. We report the first continuous time-series rainwater sampling and analysis of ~7be,^(210)Pb and ^(210)Po from two typhoons and one thunderstorm during 2015 summer in Shanghai. The depositional fluxes within individual rain events of typhoons and thunderstorms varied by a factor of 10 for ~7be, 5.7 for ^(210)Pb, 7.4 for ^(210)Po,and 7.0 for ~7be/^(210)Pb activity ratios(AR). Such large observed variations in the depositional fluxes of ~7be,^(210)Pb,^(210)Po and ~7be/^(210)Pb activity ratios were attributed to air masses injected from surrounding high pressure system adjoining the typhoon to low pressure system within the typhoon. based on ~7be/^(210)Pb activity ratios, we estimated the variations in the fraction of maritime and continental air masses into the typhoon. Observed constancy in the ^(210)Po/^(210)Pb AR indicates that the residence times of air masses contributing to the typhoon during heavy rain are similar. From a synthesis of global fallout of ~7be and ^(210)Pb during pulse events(precipitation≥50 mm from single rainout event), we quantify the importance of pulse events in the atmospheric fallout of these radionuclides.

关键词： 7be 210Pb 210Po Typhoon Thunderstorm Air masses intrusions

Hydrologic Modeling Impacts of Post-mining Land Use Changes on Streamflow of Peace River, Florida

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Chinese Geographical Science 2015年第6期25卷 728-738页

作者： ZHANG Jing mark ROSS Key Laboratory of Resource Environment and GIS in beijing Capital Normal University Department of Civil and Environmental Engineering University of South Florida

Whether mining activity results in reduced flow of surface water in the Peace River Watershed of Florida has been the subject of much debate. With increased dependence of downstream users on surface water flow of the Peace River as a source of drinking water for four coastal counties in Southwest Florida and problems of water security, the debate has been intensified. It is possible to assess relationships of mining with streamflow in the upper reaches of the Peace River basin using hydrologic modeling and identify mined sub-basins. In this work, land-use change impacts were simulated by the Hydrological Simulation Program--Fortran （HSPF） model based on geographical information system （GIS） tools, to compare pre- and post-mining streamflows at a study site of the Peace River in west-central Florida. The purpose of this study was to determine if land-use changes caused by mining have negatively impacted streamflow in the Peace River. Changes of land use were identified before and after mining activities. A coupled volume-water depth-discharge （V-h-Q） model based on stage/storage and stage/discharge was applied using HSPF for the pre-mining and post-mining models, respectively. Daily simulated post-mining hydrographs from HSPF were plotted with the calibrated pre-mining results and streamflow hydrographs from the 18 gauging stations, to compare timing of peaks, low fows and flow trends. Analyses of percent ex- ceedances of flow frequency curves of the streams indicated that most streams had similar distributions for mined （reclaimed） and pre- mining periods. In the streamflow change analysis, streamflows actually increased in mining-affected basins at nearly half the stations. Streamflows at other stations diminished. Overall from this comprehensive study, there were declines in streamflow at most gauging stations on the mainstem of the Peace River and its tributaries. The results of this study suggest that regional planning is urgently needed to propose reclamation s

关键词： post-mining land-use changes streamflow hydrologic model Hydrological Simulation Program--Fortran (HSPF) model

Extreme wave loads on submerged water intakes in shallow water

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Journal of Hydrodynamics 2015年第1期27卷 38-51页

作者： CORNETT Andrew HECIMOVICH mark NISTOR Ioan Ocean Coastal and River Engineering National Research Council Department of Civil Engineering University of Ottawa

This paper provides new guidance concerning the hydrodynamic loads on submerged intake structures located in shallow water under breaking and non-breaking waves. Results from a series of experiments conducted in a large wave flume at 1 ： 15 scale to study the hydrodynamic forces exerted on a generic intake structure located on a sloping seabed in shallow water below breaking and non-breaking irregular waves are presented. based on analysis of the experimental data, empirical relationships are developed to describe the peak loads in terms of characteristic wave parameters such as significant wave height and peak wave period. The distribution of the peak loads across different parts of the intake structure is also described. Drag and inertia force coefficients for the horizontal forcing on the intake structure and for the main structural sub-components are derived and presented. It is shown that the well-known Morison equation, with appropriate drag and inertia force coefficients, can provide reasonable estimates of the moderate horizontal loads, but the peak loads are less well predicted.

关键词： wave force water intake drag force inertia force coastal engineering

Significant association between AbO blood group and pancreatic cancer

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World Journal of Gastroenterology 2010年第44期16卷 5588-5591页

作者： Julia b Greer mark H Yazer Jay S Raval M Michael barmada Randall E brand David C Whitcomb Department of Medicine Division of GastroenterologyHepatology and NutritionUniversity of Pittsburgh School of Medicine Department of Pathology University of Pittsburgh School of Medicine The Institute for Transfusion Medicine Department of Human Genetics Graduate School of Public HealthUniversity of Pittsburgh University of Pittsburgh Cancer Institute

AIM:To evaluate whether the AbO blood group is related to pancreatic cancer risk in the general population of the United ***:Using the University of Pittsburgh's clinicalpancreatic cancer registry,the blood donor database from our local blood bank (Central blood bank),and the blood product recipient database from the regional transfusion service (Centralized Transfusion Service) in Pittsburgh,Pennsylvania,we identified 274 pancreatic cancer patients with previously determined serological AbO blood group *** AbO blood group frequency was compared between these patients and 708842 individual,community-based blood donors who had made donations to Pittsburgh's Central blood bank between 1979 and ***:The frequency of blood group A was statistically significantly higher amongst pancreatic cancer patients compared to its frequency amongst the regional blood donors [47.63% vs 39.10%,odds ratio (OR)=1.43,P=0.004].Conversely,the frequency of blood group O was significantly lower amongst pancreatic cancer patients relative to the community blood donors (32.12% vs 43.99%,OR=0.60,P=0.00007).There were limited blood group b (n=38) and Ab (n=17) pancreatic cancer patients;the overall P trend value comparing patient to donor blood groups was ***:The AbO blood group is associated with pancreatic cancer *** studies should examine the mechanism linking pancreatic cancer risk to AbO blood group.

关键词： AbO blood group Pancreatic adenocarcinoma Surveillance Risk reduction Epidemiology

A Connecticut Yankee in King Arthur's court

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A Connecticut Yankee in King Arthur's court

Validity of a noninvasive estimation of deep body temperature when wearing personal protective equipment during exercise and recovery

作者： mark Twain edited by Henry b. Wonham.

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Military Medical Research 2019年第4期6卷 328-339页

作者： Andrew P.Hunt mark J.buller Matthew J.Maley Joseph T.Costello Ian b.Stewart School of Exercise and Nutrition Sciences&Institute of Health and biomedical Innovation Queensland University of TechnologyBrisbaneQLDAustralia United States Army Research Institute of Environmental Medicine NatickMAUSA Extreme Environments Laboratory Department of Sport and Exercise ScienceUniversity of PortsmouthPortsmouthUK

background:Deep body temperature is a critical indicator of heat ***,direct measures are often invasive,costly,and difficult to implement in the *** study assessed the agreement between deep body temperature estimated from heart rate and that measured directly during repeated work bouts while wearing explosive ordnance disposal(EOD)protective clothing and during ***:Eight males completed three work and recovery periods across two separate *** consisted of treadmill walking on a 1%incline at 2.5,4.0,or 5.5 km/h,in a random order,wearing EOD protective *** temperature and relative humidity were maintained at 24℃and 50%[Wet bulb globe temperature(WbGT)(20.9±1.2)℃]or 32℃and 60%[WbGT(29.0±0.2)℃]on the separate days,*** rate and gastrointestinal temperature(TGI)were monitored continuously,and deep body temperature was also estimated from heart rate(ECTemp).Results:The overall systematic bias between TGI and ECTemp was 0.01℃with 95%limits of agreement(Lo A)of±0.64℃and a root mean square error of 0.32℃.The average error statistics among participants showed no significant differences in error between the exercise and recovery periods or the environmental *** TGI levels of(37.0–37.5)℃,(37.5–38.0)℃,(38.0–38.5)℃,and>38.5℃,the systematic bias and±95%Lo A were(0.08±0.58)℃,(–0.02±0.69)℃,(–0.07±0.63)℃,and(–0.32±0.56)℃,***:The findings demonstrate acceptable validity of the ECTemp up to 38.5℃.Conducting work within an ECTemp limit of 38.4℃,in conditions similar to the present study,would protect the majority of personnel from an excessive elevation in deep body temperature(>39.0℃).

关键词： Protective clothing body core temperature Heat strain Heat stress Kalman filter Explosive ordnance disposal

Functional Inferences of Environmental Coccolithovirus biodiversity

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Virologica Sinica 2013年第5期28卷 291-302页

作者： Jozef I Nissimov mark Jones Johnathan A Napier Colin b Munn Susan A Kimmance Michael J Allen Plymouth Marine Laboratory Prospect Place University of Nottingham School of BiosciencesSutton Bonington Campus Department of biological Chemistry Rothamsted Research School of Marine Science & Engineering Plymouth University

The cosmopolitan calcifying alga Emiliania huxleyi is one of the most abundant bloom forming coccolithophore species in the oceans and plays an important role in global biogeochemical cycling. Coccolithoviruses are a major cause of coccolithophore bloom termination and have been studied in laboratory, mesocosm and open ocean studies. However, little is known about the dynamic interactions between the host and its viruses, and less is known about the natural diversity and role of functionally important genes within natural coccolithovirus communities. Here, we investigate the temporal and spatial distribution of coccolithoviruses by the use of molecular fingerprinting techniques PCR, DGGE and genomie sequencing. The natural biodiversity of the virus genes encoding the major capsid protein （MCP） and serine palmitoyltransferase （SPT） were analysed in samples obtained from the Atlantic Meridional Transect （AMT）, the North Sea and the L4 site in the Westem Channel Observatory. We discovered nine new coccolithovirus genotypes across the AMT and L4 site, with the majority of MCP sequences observed at the deep chlorophyll maximum layer of the sampled sites on the transect. We also found four new SPT gene variations in the North Sea and at L4. Their translated fragments and the full protein sequence of SPT from laboratory strains EhV-86 and EhV-99b 1 were modelled and revealed that the theoretical fold differs among strains. Variation identified in the structural distance between the two domains of the SPT protein may have an impact on the catalytic capabilities of its active site. In summary, the combined use of ＇standard＇ markers （i.e. MCP）, in combination with metabolically relevant markers （i.e. SPT） are useful in the study of the phylogeny and functional biodiversity of coccolithoviruses, and can provide an interesting intracellular insight into the evolution of these viruses and their ability to infect and replicate within their algal hosts.

关键词： Coccolithovirus Major capsid protein Serine palmitoyltransferase Functional biodiversity

Shedding Light on the Crystallographic Etching of Multi-Layer Graphene at the Atomic Scale

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Nano Research 2009年第9期2卷 695-705页

作者： Franziska Schäffel Jamie H.Warner Alicja bachmatiuk bernd Rellinghaus bernd büchner Ludwig Schultz mark H.Rümmeli IFW Dresden P.O.Box 270116D-01171 DresdenGermany Department of Materials University of OxfordParks Rd.Oxford OX13PHUnited Kingdom

The controlled etching of graphite and graphene by catalytic hydrogenation is potentially a key engineering route for the fabrication of graphene nanoribbons with atomic *** hydrogenation mechanism,though,remains poorly *** this study we exploit the benefi ts of aberration-corrected high-resolution transmission electron microscopy to gain insight to the hydrogenation *** etch tracks are found to be commensurate with the graphite *** particles at the head of an etch channel are shown to be faceted and the angles between facets are multiples of 30°.Thus,the angles between facets are also commensurate with the graphite *** addition,the results of a post-annealing step suggest that all catalyst particles even if they are not involved in etching are actively forming methane during the hydrogenation ***,the data point against carbon dissolution being a key mechanism during the hydrogenation process.

关键词： Graphene graphene nanoribbons catalytic hydrogenation nanoparticles