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Understorey species distinguish late successional and ancient forests after decades of minimum human intervention: A case study from Slovenia

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Forest Ecosystems 2023年第1期10卷 92-101页

作者： Mirjana Sipek tim Ravnjak nina Sajna University of Maribor Faculty of Natural Sciences and MathematicsKoroska c.1602000MariborSlovenia

The main species composition drivers in temperate deciduous forests are environmental conditions, a stand?s age and the site history, e.g., the succession stage and past land use, as well as disturbance regime and current management. We compared plant species diversity and composition in late successional and ancient forests, cooccurring on the same small river island applying species accumulation curves and nonmetric multidimensional scaling, respectively. Given the island?s geomorphological characteristics, we expected these to be very similar before human intervention in the past. The forests experienced differing disturbance regimes in the past, while over the last 30 years, human intervention has been the same and reduced to a minimum. The ancient forest in this study had two major characteristics defining it as old, mature forest: continuity of presence for more than 200years and specific composition. The late successional forest experienced major disturbance in the 20th century and was allowed natural regeneration by bordering on the ancient forest, representing a potential species pool,and by decades of minimum human intervention. Our results showed that, even though there was no difference in species richness, we could still detect differences between the forests, particularly in the abundance and species composition of the understorey, among which geophytes had the most indicative importance. To make our results useful on a broader scale, we composed from the literature a species list of plants indicative for ancient forest and tested its application. These results are important for distinguishing between old and mature secondary stands and particularly for identifying old forest stands, which should be conserved and, in the case of fragmented landscapes, included in a network connecting forest fragments.

关键词： Forest community Successional forest Indicator plants Plant diversity Understorey Geophytes

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LiDAR mapping of ground damage in a heading re-orientation case study

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International journal of Mining Science and Technology 2021年第1期31卷 67-74页

作者： nicole Evanek Brent Slaker Anthony Iannacchione tim Miller national Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA University of Pittsburgh PittsburghPA 15260USA East Fairfield Coal Company North LimaOH 44452USA

The Subtropolis Mine is a room-and-pillar mine extracting the Vanport limestone near Petersburg,Ohio,*** February of 2018,mine management began implementing a heading re-orientation to better control the negative effects of excessive levels of horizontal *** conditions in the headings improved,but as expected,stress-related damage concentrated within *** mine operator has worked to lessen the impact of the instabilities in the outby crosscuts by implementing several engineering *** the implementation of each control,conditions were monitored and analyzed using observational and measurement techniques including 3D LiDAR *** the heading re-orientation,several 3D LiDAR surveys have been conducted and analyzed by researchers from the national Institute for Occupational Safety and Health(nIOSH).This study examines(1)the characteristics of each 3D LiDAR survey,(2)the change in the detailed strata conditions in response to stress concentrations,and(3)the change detection techniques between 3D LiDAR surveys to assess entry ***,the 3D LiDAR surveys proved to be a useful tool for characterizing ground instability and assessing the effectiveness of the engineering controls used in the heading re-orientation at the Subtropolis Mine.

关键词： Ground control Limestone Horizontal stress Stress control layout Crosscut Windows

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Effect of vertical overturning circulation scale and moist static energy tendency on MjO phase speed

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Atmospheric and Oceanic Science Letters 2022年第1期15卷 68-75页

作者： Feng Hu tim Li School of Geographic Information and Tourism Chuzhou UniversityChuzhouChina Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjingChina International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaiiUSA

The combined effects of vertical overturning circulation(VOC) zonal length scale and moist static energy(MSE)tendency zonal asymmetry on MjO phase speed were investigated based on diagnosis of ERA-Interim data over a 40-year period(1979-2019).In a key region(80°-100°E),128 MjO events were *** was found that the larger the VOC zonal length scale,the faster the MjO eastward *** correlation coefficient between them was 0.52,exceeding the 99% confidence level.A significant positive correlation(0.59) was also identified between the phase speed and MSE tendency zonal asymmetry.A linear regression model based on the aforementioned two parameters was constructed,and the phase speed could be estimated based on the *** correlation coefficient between the reconstructed phase speed and its observed counterpart was 0.73,exceeding the 99% confidence level with an F-test.A composite analysis of the fast and slow groups indicated that the VOC zonal length scale was modulated by the background *** El nino(La ni?a)-like SST pattern and associated precipitation anomalies promoted a larger(smaller) VOC zonal length scale and thus a faster(slower)propagation speed.A sensitivity test with a reference point in a different longitudinal zone(120°-140°E) was ***,there were significant relationships between the MjO phase speed and the two *** correlation between the reconstructed and observed phase speed was 0.67,exceeding the 99% confidence level.

关键词： Vertical overturning circulation MjO phase speed Moist static energy tendency Linear regression model

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An investigation into intermittent electrification strategies and an analysis of resulting CO_(2) emissions using a high-fidelity train model

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Railway Engineering Science 2021年第3期29卷 314-326页

作者： Bilal M.Abdurahman tim Harrison Christopher P.Ward William j.B.Midgley Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughborough LE113TUUK

A near-term strategy to reduce emissions from rail vehicles,as a path to full electrification for maximal decarbonisation,is to partially electrify a route,with the remainder of the route requiring an additional self-powered traction *** rail vehicles are usually powered by a diesel engine when not operating on electrified track and are referred to as bi-mode *** paper analyses the benefits of discontinuous electrification compared to continuous electrification using the CO_(2)estimates from a validated high-fidelity bi-mode(diesel-electric)rail vehicle *** analysis shows that 50%discontinuous electrification provides a maximum of 54%reduction in operational CO_(2)emissions when compared to the same length of continuously electrified *** highest emissions savings occurred when leaving train stations where vehicles must accelerate quickly to line *** results were used to develop a linear regression model for fast estimation of CO_(2)emissions from diesel running and electrification *** model was able to estimate the CO_(2)emissions from a route to within 10%of that given by the high-fidelity ***,additional considerations such as cost and the embodied CO_(2)in electrification infrastructure were analysed to provide a comparison between continuous and discontinuous *** electrification can cost up to 56%less per reduction in lifetime emissions than continuous electrification and can save up to 2.3 times more lifetime CO_(2)per distance electrified.

关键词： Railway electrification CO_(2)reduction Discontinuous electrification Bi-mode rail vehicle

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Multi-scale drivers of soil resistance predict vulnerability of seasonally wet meadows to trampling by pack stock animals in the Sierra nevada,USA

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Ecological Processes 2020年第1期9卷 364-377页

作者： joy S.Baccei Mitchel P.McClaran tim j.Kuhn Stephen C.Hart Environmental Systems Graduate Group University of CaliforniaMercedCA 95343USA UC Merced Vernal Pools and Grassland Reserve UC Merced Natural Reserve SystemMercedCA 95343USA School of natural Resources and the Environment University of ArizonaTucsonAZ 85721USA Resources Management and Science Yosemite National ParkEl PortalCA 95318USA Department of Life&Environmental Sciences and Sierra nevada Research Institute University of CaliforniaMercedCA 95343USA.

Background:Meadow ecosystems have important ecological functions and support socioeconomic services,yet are subject to multiple stressors that can lead to rapid *** the Sierra nevada of the western USA,recreational pack stock(horses and mules)use in seasonally wet mountain meadows may lead to soil trampling and meadow degradation,especially when soil water content is high and vegetation is ***:In order to improve the ability to predict meadow vulnerability to soil disturbance from pack stock use,we measured soil resistance(SR),which is an index of vulnerability to trampling disturbance,at two spatial scales using a stratified-random sampling *** then compared SR to several soil and vegetation explanatory variables that were also measured at the two spatial scales:plant community type(local scale)and topographic gradient class(meadow scale).Results:We found that local-scale differences in drivers of SR were contingent on the meadow scale,which is important because multiple spatial scale evaluation of ecological metrics provides a broader understanding of the potential controls on ecological processes than assessments conducted at a single spatial *** also found two contrasting explanatory models for drivers of SR at the local scale:(1)soil gravimetric water content effects on soil disaggregation and(2)soil bulk density and root mass influence on soil *** resistance was insufficient to sustain pack stock use without incurring soil deformation in wet plant communities,even when plant cover was maximal during a major ***:Our study provides new information on seasonally wet meadow vulnerability to trampling by pack stock animals using multi-scale drivers of SR,including the contrasting roles of soil disaggregation,friction,and *** work aims to inform meadow management efforts in the Sierra nevada and herbaceous ecosystems in similar regions that are subject to seasonal soil saturation and livestock u

关键词： Hydrogeomorphic classification Hydrologic regime Pack stock Plant communities Soil properties Soil strength

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Unraveling giant Cu（110） surface restructuring induced by a non-planar phthalocyanine

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nano Research 2018年第5期11卷 2605-2611页

作者： nataliya Kalashnyk Luke A. Rochford Dongzhe Li Alexander Smogunov Yannick j. Dappe tim S. jones Laurent Guillemot Institut des Sciences Moleculaires d'Orsay CNRS Universite Paris-Sud 11 Orsay 91405 France School of Chemistry The University of Birmingham Birmingham B15 2TT UK Department of Physics University ofKonstanz Konstanz 78457 Germany SPEC CEA CNRS Universite Paris-Saclay CEA Saclay Gif-sur-Yvette Cedex 91191 France

The surface stability of coinage metals is paramount when they are used as electrode materials for functional electronic devices incorporating organic semiconductors. In this work, it is shown that the adsorption of non-planar vanadyl phthalocyanine molecules on Cu（110） drastically restructured the metal surface at room temperature, which was further enhanced upon moderate annealing. Scanning tunneling microscopy imaging demonstrated that the surface was restructured at step edges into sawtooth features that gradually replaced the （110） terraces. The edges of the modified steps were preferentially composed of chiral （1×6） kink sites decorated with vanadyl phthalocyanine molecules adsorbed in a tilted configuration with the oxygen atom pointing downwards. These results can have a strong impact on the optimization of the performance of organic devices integrated with phthalocyanine molecules.

关键词： surface restructuring step-etching chiral kink phthalocyanine

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A review of the resistome within the digestive tract of livestock

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journal of Animal Science and Biotechnology 2022年第3期13卷 642-661页

作者： Tao Ma tim A.McAllister Le Luo Guan Key laboratory of Feed Biotechnology of the Ministry of Agriculture Institute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081China Department of Agricultural Food and Nutritional ScienceUniversity of AlbertaT6G2P5EdmontonABCanada Lethbridge Research and Development Centre LethbridgeAB T1J 4P4Canada

Antimicrobials have been widely used to prevent and treat infectious diseases and promote growth in food-production ***,the occurrence of antimicrobial resistance poses a huge threat to public and animal health,especial y in less developed countries where food-producing animals often intermingle with *** limit the spread of antimicrobial resistance from food-production animals to humans and the environment,it is essential to have a comprehensive knowledge of the role of the resistome in antimicrobial resistance(AMR),The resistome refers to the col ection of al antimicrobial resistance genes associated with microbiota in a given *** dense microbiota in the digestive tract is known to harbour one of the most diverse resistomes in *** of the resistome in the digestive tract of humans and animals are increasing exponential y as a result of advancements in next-generation sequencing and the expansion of bioinformatic resources/tools to identify and describe the *** this review,we outline the various tools/bioinformatic pipelines currently available to characterize and understand the nature of the intestinal resistome of swine,poultry,and *** then propose future research directions including analysis of resistome using long-read sequencing,investigation in the role of mobile genetic elements in the expression,function and transmission of *** review outlines the current knowledge and approaches to studying the resistome in food-producing animals and sheds light on future strategies to reduce antimicrobial usage and control the spread of AMR both within and from livestock production systems.

关键词： Antimicrobial resistance Antimicrobial resistance gene Digestive tract Food-producing animal Metagenomic sequencing Resistome

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Heavy Precipitation over the jing–jin–ji Region in Early October: What Controls Its Interannual Variability?

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journal of Meteorological Research 2022年第4期36卷 586-600页

作者： jing FEnG tim LI ji WAnG Linna ZHAnG Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate andEnvironmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC–FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Beijing Meteorological Information Center China Meteorological AdministrationBeijing 100089China International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA Beijing Municipal Climate Center Beijing 100089China Beijing Meteorological Observatory Beijing 100089China

Heavy regional precipitation(HRP)over Beijing,Tianjin,and Hebei Province(the jing–jin–ji region or jjj)in early October(1–10 October)is a high-impact climate event because of travel and outdoor activities by exceptionally large population during the Chinese national Day Holidays(CnDH).What causes the year-to-year variation of the HRP during early October is investigated through an observational *** is found that the HRP arises from moisture transport by southerly anomalies to the west of an anomalous low-level anticyclone over the subtropical northwestern Pacific(SnWP).Sensitivity numerical experiments reveal that the low-level anticyclonic anomaly is caused by a dipole heating pattern over tropical western and central Pacific associated with a La niña-like SST anomaly(SSTA)pattern in the Pacific and by a negative heating anomaly over north *** latter connects the SnWP anticyclone through a Rossby wave *** ascent associated with a positive heating anomaly over the tropical western Pacific may strengthen the local Hadley Cell,contributing to maintenance of the low-level anomalous anticyclone over SnWP and extending westwards of the western Pacific subtropical high(WPSH).Therefore,both the tropical Pacific and midlatitude heating signals over north Europe may be potential predictors for HRP forecast in the jjj region in early October.

关键词： heavy regional precipitation(HRP)in jing–jin–ji(jjj) Beijing Tianjin and Hebei Province water vapor(WV)transport Rossby wave train diabatic heating anomalies La niña-like SST anomaly

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Development of a CO_2 Tolerant Fischer-Tropsch Catalyst:from Laboratory to Commercial-Sca1e Demonstration in Alaska

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journal of natural Gas Chemistry 2004年第1期13卷 1-9页

作者： joep j H M Font Freide tim D Gamlin j Richard Hensman Barry nay Christopher Sharp BP Exploration Operating Company Chertsey RoadSunbury on ThamesMiddlesexTWl6 7LNEnglandDavy Process Technology Lid 20 Eastbourne TerraceLondon W2 6LEEnglandDavy Process Technology Lid 20 Eastbourne TerraceLondon W2 6LEEnglandBP Chemicals LtdChertsey RoadSunbury on ThamesMiddlesexTW16 7LLEnglandBP Chemicals LtdChertsey RoadSunbury on ThamesMiddlesexTW16 7LLEngland

This article describes the development of BP's Fischer-Tropsch catalyst, used for the conversion of carbon monoxide and hydrogen into liquid hydrocarbons. It covers the 18 year period from the early eighties, when laboratory scale preparations and micro-reactors were heavily used, right through to the present day with the commercial scale manufacture and proving of the finished catalyst in BP's new ＄86 million gas to liquids demonstration facility in nikiski, Alaska. Extensive performance testing and scale-up experiments have been successfully carried out, all proof that a laboratory preparation can indeed be translated into a commercial manufacturing process. In addition, the resulting catalyst does not only meet the process design targets, but also exhibits enhanced stability and is tolerant to carbon dioxide. Above all, a commercial scale, fixed bed Fischer-Tropsch catalyst is now available and ready for licensing. Manufacturing procedures and quality control have all been successfully detailed and transferred to the commercial manufacturer.

关键词： carbon dioxide Fisher-Tropsch development syngas commercial catalyst

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Spin frustration and magnetic ordering in triangular lattice antiferromagnet Ca_3Conb_2O_9

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Chinese Physics B 2015年第12期24卷 549-553页

作者：代佳周萍王朋帅庞斐 tim j.Munsie Graeme M.Luke 张金珊于伟强 Department of Physics Renmin University of China Department of Physics and Astronomy Mc Master University Canadian Institute for Advanced Research School of Energy Power and Mechanical Engineering North China Electric Power University

We synthesized a quasi-two-dimensional distorted triangular lattice antiferromagnet Ca3Conb2O9, in which the effective spin of Co2＋is 1/2 at low temperatures, whose magnetic properties were studied by dc susceptibility and magnetization techniques. The x-ray diffraction confirms the quality of our powder samples. The large Weiss constant θCW --55 K and the low neel temperature Tn- 1.45 K give a frustration factor f =｜ θCW/Tn｜≈ 38, suggesting that Ca3 Co nb2O9resides in strong frustration regime. Slightly below Tn, deviation between the susceptibility data under zero-field cooling（ZFC）and field cooling（FC） is observed. A new magnetic state with 1/3 of the saturate magnetization Ms is suggested in the magnetization curve at 0.46 K. Our study indicates that Ca3 Co nb2O9is an interesting material to investigate magnetism in triangular lattice antiferromagnets with weak anisotropy.

关键词： Ca3Conb2O9 triangular lattice frustration spin glass magnetization plateau

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