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Recovery of Baikiaea forest of southwestern Zambia from shifting cultivation and its implications for sustainable management

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Journal of Forestry Research 2019年第2期30卷 497-506页

作者： Filipo Zulu stephen Syampungani Peter Fushike National Science and Technology Council (NSTC) School of Natural Resources Copperbelt University

We studied the dominant species by age category of re-growth, and how subsistence forest use through shifting cultivation impacted on the floristic composition of Baikiaea forest. For re-growth stands, variable sampling method was adopted in data collection while in mature stands, a sample plot size of 50 m 9 50 m was used at each of three study sites. Distribution of species by age categories showed that shrub, herb, and grass species were abundant in young re-growth stands while woody vegetation became common with increasing age of the re-growth stand. Hierarchical clustering for common woody species showed several species associations with age categories and also with relatively undisturbed woodland. Common regeneration mechanisms of key woody species were mainly by seed(48%), coppicing(40%) and root suckers(12%). The young re-growth stands of 6–10 and 11–15 years were characterized by B. petersiana, ***, Combretum zeyheri, and Guibourtia coleosperma. Older stands(16–20 years after abandonment) were characterized by B. plurijuga, Pterocarpus antunesii, and Baphia massiensis, thus closely mimicking the relatively undisturbed forest whose dominant key woody species were B. plurijuga, P. antunesii, and G. coloesperma. There were many stems in younger stands(2–5 years) and fewer stems in older re-growth stands of 16–20 years after abandonment following shifting cultivation. Older regrowth stands(16–20 years) were similar to undisturbed stands(P \ 0.005). The similarity between re-growth stands of 16–20 years and control stands demonstrates the recovery of Baikiaea forest over time after cessation of shifting agriculture. Baikiaea forest requires some disturbance to perpetuate the dominant species and begins to show signs of recovery from shifting cultivation within16–20 years after abandonment. This is contrary to assertions that this ecosystem could take up to about 100 years for abandoned fields to begin showing signs of

关键词： Regeneration dynamics Species diversity Tree species dominance management model Shifting cultivation

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Visually modelling Collaborative Research into Innovative Community Disaster Resilience Practice,Strategy,and Governance

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International Journal of Disaster Risk Science 2015年第3期6卷 282-294页

作者： Thomas J.Huggins Robin Peace stephen R.Hill David m.Johnston Alicia Cuevas muniz Joint Centre for Disaster Research School of PsychologyMassey University School of Psychology Massey University School of Psychology Massey University Joint Centre of Disaster ResearchMassey University Faculty of Science University of Colima

In 2013 a new collaborative center was established in Wellington, New Zealand to focus on integrating resilience research with the region’s community disaster resilience strategy. An earlier study with parties to this center had indicated that researcher and practitioner groups were divided by attention to their own immediate knowledge and skills, but agreed there was a need to maximize community resilience benefits amongst a regional population. An action research workshop of researchers and practitioners used a visual logic model to focus on the pragmatic benefits of improving community resilience. The visual logic model was used to design research activities that would improve the regional community resilience strategy, which was still in an early implementation *** of 14 workshop participants were interviewed following the workshop. Statistical content analysis of interview data highlighted certain strengths of the action research process: visual monitoring and evaluation planning was a catalyst for complicated conversations between two very different groups of professionals; and researchers became more focused on practical issues as a result. Other findings suggested that in future collaborative researchgovernance would benefit from wider cycles of strategic intelligence, enhanced research contributions, and the use of different information formats for different *** formats for different purposes should also be considered when developing and implementing large-scale disaster risk reduction policies and strategies.

关键词： Collaborative research Community resilience Content analysis Emergency management Visual communication

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Seed value influences cache pilfering rates by desert rodents

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Integrative Zoology 2019年第1期14卷 75-86页

作者： stephen B.VANDER WALL Lindsay A.DImITRI William S.LONGLAND Joseph D.m.WHITE Department of Biology and Program in Ecology Evolution and Conservation BiologyUniversity of NevadaRenoUSA USDA Agricultural Research ServiceRenoNevadaUSA Department of Biological Sciences University of Cape TownCape TownRepublic of South Africa

Some rodents gather and store *** many seeds they gather and how they treat those seeds is largely determined by seed traits such as mass,nutrient content,hardness of the seed coat,presence of secondary compounds,and germination *** their consumption and dispersal of seeds,rodents act as agents of natural selection on seed traits,and those traits influence how rodents *** seeds that are scatter-hoarded by rodents are pilfered,or stolen,by other rodents,and seed traits also likely influence pilfering rates and seed fates of pilfered *** clarify coevolutionary relationships between rodents and the plants that they disperse,one needs to understand the role of seed traits in rodent foraging *** compared how the seeds of 4 species of plants that are dispersed by scatter-hoarding animals and that differ in value(singleleaf piñon pine,Pinus monophylla;desert peach,Prunus andersonii;antelope bitterbrush,Purshia tridentata;Utah juniper,Juniperus osteosperma)were pilfered and recached by *** hundred artificial caches of the 4 seed species(25 per species)were prepared,and removal by rodents was *** pilfered high-value seeds more rapidly than the other *** peach seeds,which contain toxic secondary compounds,were more frequently *** low value seeds like Utah juniper and antelope bitterbrush were pil-fered more slowly and were sometimes left at cache sites,and seeds of the latter species were transported shorter distances to new cache *** background density of seeds also appeared to influence the relative value of seeds.

关键词： desert rodents food storage granivory pilfering scatter-hoarding seed dispersal seed traits

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A machine learning approach to tungsten prospectivity modelling using knowledge-driven feature extraction and model confidenc

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Geoscience Frontiers 2020年第6期11卷 2067-2081页

作者： Christopher m.Yeomans Robin K.Shail stephen Grebby Vesa Nykanen maarit middleton Paul A.J.Lusty Camborne School of mines College of EngineeringMathematics and Physical SciencesUniversity of ExeterPenryn CampusPenrynCornwallTR109FEUK British Geological Survey Environmental Science CentreKeyworthNottinghamshireNG125GGUK University of Nottingham Nottingham Geospatial InstituteInnovation ParkNottinghamNG72TUUK Geological Survey of Finland P.O.Box 77FI-96101RovaniemiFinland

Novel mineral prospectivity modelling presented here applies knowledge-driven feature extraction to a datadriven machine learning approach for tungsten *** method emphasises the importance of appropriate model evaluation and develops a new Confidence metric to generate spatially refined and robust exploration *** data-driven Random ForestTm algorithm is employed to model tungsten mineralisation in SW England using a range of geological,geochemical and geophysical evidence layers which include a depth to granite evidence *** models are presented,one using standardised input variables and a second that implements fuzzy set theory as part of an augmented feature extraction *** use of fuzzy data transformations mean feature extraction can incorporate some user-knowledge about the mineralisation into the *** typically subjective approach is guided using the Receiver Operating Characteristics(ROC)curve tool where transformed data are compared to known training *** modelling is conducted using 34 known true positive samples with 10 sets of randomly generated true negative samples to test the random effect on the *** two models have similar accuracy but show different spatial distributions when identifying highly prospective *** analysis shows that the fuzzy-transformed model is a better discriminator and highlights three areas of high prospectivity that were not previously *** Confidence metric,derived from model variance,is employed to further evaluate the *** new metric is useful for refining exploration targets and highlighting the most robust areas for follow-up *** fuzzy-transformed model is shown to contain larger areas of high model confidence compared to the model using standardised ***,legacy mining data,from drilling reports and mine descriptions,is used to further validate the fuzzy-transformed model and gauge the depth of potential *** of m

关键词： machine learning mineral prospectivity modelling mineral exploration Random ForestTm Tungsten SW England

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An Analysis of Crosswalks from Research Data Schemas to ***

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Data Intelligence 2023年第1期5卷 100-121页

作者： mingfang Wu stephen m.Richard Chantelle Verhey Leyla Jael Castro Baptiste Cecconi Nick Juty Australian Research Data Commons MelbourneVictoria 3145Australia US Geoscience Information Network Neward DE 19716-7501USA International Science Council World Data SystemVictoria BC V8N 1V8Canada ZB mED-Information Centre for Life Sciences Cologne 50931Germany Observatoire de Paris-PSL Paris Astronomical Data CenterParis 75001France Department of Computer Science The University of ManchesterOxford RoadManchester M139PLUK

The increased number of data repositories has greatly increased the availability of open *** enable broad discovery and access to research dataset,some data repositories have begun leveraging the web architecture by embedding structured metadata markup in dataset web landing pages using vocabularies from *** and *** paper aims to examine metadata interoperability for supporting global data ***,the paper reports a survey on which metadata schema has been adopted by participating data repositories,and presents an analysis of crosswalks from fourteen research data schemas to *** analysis indicates most descriptive metadata are interoperable among the schemas,the most inconsistent mapping is the rights metadata,and a large gap exists in the structural metadata and controlled vocabularies to specify various property *** analysis and collated crosswalks can serve as a reference for data repositories when they develop crosswalks from their own schemas to ***,and provide the research data community a benchmark of structured metadata implementation.

关键词： metadata schema *** metadata interoperability FAIR(meta)data metadata schemas crosswalk research data schemas

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Incorporating within- and between-patch resource selection in identification of critical habitat for brood-rearing greater sage-grouse

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Ecological Processes 2015年第1期4卷 57-71页

作者： matthew R Dzialak Chad V Olson stephen L Webb Seth m Harju Jeffrey B Winstead Hayden-Wing Associates LLCNatural Resource ConsultantsLaramieWY 2308 South 8th StreetUSA The Samuel Roberts Noble Foundation 2510 Sam Noble ParkwayArdmoreOK 73401USA

Introduction:Incorporating information on animal behavior in resource-based predictive modeling(e.g.,occurrence mapping)can elucidate the relationship between process and spatial pattern and depict habitat in terms of its structure as well as its *** this paper,we assigned location data on brood-rearing greater sage-grouse(Centrocercus urophasianus)to either within-patch(encamped)or between-patch(traveling)behavioral modes by estimating a movement-based relative displacement *** were to estimate and validate spatially explicit models of within-versus between-patch resource selection for application in habitat management and compare these models to a non-behaviorally adjusted ***:A single model,the vegetation and water resources model,was most plausible for both the encamped and traveling modes,including the non-behaviorally adjusted *** encamped,sage-grouse selected for taller shrubs,avoided bare ground,and were closer to mesic *** sage-grouse selected for greater litter cover and herbaceous *** for proximity to mesic areas was common to both encamped and traveling modes and to the non-behaviorally adjusted *** non-behaviorally adjusted map was similar to the encamped model and validated ***,we observed different selection patterns during traveling that could have been masked had behavioral state not been accounted ***:Characterizing habitat that structured between-patch movement broadens our understanding of the habitat needs of brood-rearing sage-grouse,and the combined raster surface offers a reliable habitat management tool that is readily amenable to application by GIS users in efforts to focus sustainable landscape management.

关键词： Behavioral mode Brood-rearing Centrocercus urophasianus Conditional logistic regression Conservation planning Information-theoretic approach Relative displacement index Species occurrence model

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Campylobacter concisus and inflammatory bowel disease

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World Journal of Gastroenterology 2014年第5期20卷 1259-1267页

作者： Li Zhang Hoyul Lee michael C Grimm stephen m Riordan Andrew S Day Daniel A Lemberg School of Biotechnology and Biomo-lecular Sciences University of New South Wales St George and Sutherland Clinical School University of New South Wales Gastrointestinal and Liver Unit The Prince of Wales Hospital Prince of Wales Clinical School University of New South Wales Department of Gastroenter-ology Sydney Children’s Hospital Department of Pediatrics University of Otago Christchurch School of Women’s and Children’s Health University of New South Wales

Investigation of the possible role of Campylobacter concisus(C. concisus) in inflammatory bowel disease(IBD) is an emerging research area. Despite the association found between C. concisus and IBD, it has been difficult to explain how C. concisus, a bacterium that is commonly present in the human oral cavity, may contribute to the development of enteric diseases. The evidence presented in this review shows that some C. concisus strains in the oral cavity acquired zonula occludens toxin(zot) gene from a virus(prophage) and that C. concisus Zot shares conserved motifs with both Vibrio cholerae Zot receptor binding domain and human zonulin receptor binding domain. Both Vibrio cholerae Zot and human zonulin are known to increase intestinal permeability by affecting the tight junctions. Increased intestinal permeability is a feature of IBD. Based on these data, we propose that a primary barrier function defect caused by C. concisus Zot is a mechanism by which zot-positive C. concisus strains may trigger the onset and relapse of IBD.

关键词： Campylobacter concisus Inflammatory bowel disease Zonula occludens toxin Tight junctions Intestinal permeability

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Void fill and support techniques to stabilize drift excavated through a transition zone mined by a TBm at the Stillwater mine

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International Journal of mining Science and Technology 2017年第1期27卷 71-76页

作者： Johnson Josh Jacobs Curt Ferster mark Tadolini stephen Stillwater mining Company NyeMT 59061USA minova GeorgetownKYUSA

Stillwater mining Company is the only U.S. producer of platinum group metals （PGms） and the largest producer outside of South Afiica and Russia. The company controls a considerable portion of the J-m reef and is currently developing the ＂Blitz Project,＂ which will provide a main haulage level, ore pass systems, backfill plants, and fiow-through ventilation to increase production and ensure sustainable extraction of this critical strategic mineral. While driving two sub-parallel footwall laterals 8125 m in length, one of the development drifts experienced a massive fall in a geologically disturbed area created by a mafic dike intrusion. Combinations of a void fill material （Tekseal）, polyurethane injection, fore poling coupled with steel arches, and supplemental bolting allow safe and efficient advance through this geologically dis- turbed zone. This paper presents the details of this project.

关键词： TBm Ground Dike Cutterhead

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Coronary artery occlusion after arterial switch operation in an asymptomatic 15-year-old boy

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World Journal of Clinical Cases 2016年第8期4卷 219-222页

作者： Ashish P Saini stephen E Cyran Steven m Ettinger Linda B Pauliks Division of Pediatric Cardiology Department of Pediatrics Penn State Hershey Medical College Division of Cardiology Heart and Vascular InstitutePenn State Hershey College of Medicine

A 15-year-old boy with transposition of the great arteries(TGA) and neonatal arterial switch operation(ASO) presented with complete occlusion of the left main coronary artery(LmCA). Intra-operatively, an intramural left coronary artery was identified. Therefore, since age 7 years he had a series of screening exercise stress tests. At 13 years old, he had 3 to 4 mm ST segment depression in the infero-lateral leads without symptoms. This progressed to 4.2 mm inferior ST segment depression at 15 years old with normal stress echocardiogram. Sestamibi myocardial perfusion scan and cardiac magnetic resonance imaging was inconclusive. Therefore, a coronary angiogram was obtained which showed complete occlusion of the LmCA with ample collateralization from the right coronary artery system. This was later confirmed on a computed tomogram(CT) angiogram, obtained in preparation of coronary artery bypass grafting. The case illustrates the difficulty of detecting coronary artery stenosis and occlusion in young patients with rich collateralization. Coronary CT angiogram and conventional angiography were the best imaging modalities to detect coronary anomalies in this adolescent with surgically corrected TGA. Screening CT angiography may be warranted for TGA patients, particularly for those with known coronary anomalies.

关键词： Transposition of the great vessels Arterial switch operation Coronary angiography Ergometry Coronary occlusion

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Zwitterion-doped liquid crystal speckle reducers for immersive displays and vectorial imaging

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Light(Science & Applications) 2023年第11期12卷 2363-2377页

作者： Yihan Jin Nathan P.Spiller Chao He Grahame Faulkner martin J.Booth Steve J.Elston stephen m.morris Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK

Lasers possess many attractive features(e.g.,high brightness,narrow linewidth,well-defined polarization)that make them the ideal illumination source for many different scientific and technological endeavors relating to imaging and the display of high-resolution ***,their high-level of coherence can result in the formation of noise,referred to as speckle,that can corrupt and degrade ***,we demonstrate a new electro-optic technology for combatting laser speckle using a chiral nematic liquid crystal(LC)dispersed with zwitterionic *** are presented that demonstrate when driven at the optimum electric field conditions,the speckle noise can be reduced by>90%resulting in speckle contrast(C)values of C=0.07,which is approaching that required to be imperceptible to the human *** LC technology is then showcased in an array of different display and imaging applications,including a demonstration of speckle reduction in modern vectorial laser-based imaging.

关键词： polarization speckle crystal

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