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Wildfire yields a distinct turnover of the beetle community in a semi-natural pine forest in northern Sweden

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Ecological Processes 2020年第1期9卷 505-516页

作者： Emelie Fredriksson Roger Mugerwa Pettersson j.rgen Naalisvaara Therese Löfroth Wildlife Fishand Environmental studiesSwedish University of Agricultural SciencesSkogsmarksgränd 1790183 UmeåSweden County Administrative Board of Norrbotten Stationsgatan 597238 LuleåSweden

Background:Fires have been an important natural disturbance and pervasive evolutionary force in the boreal ***,fire suppression has made forest fires rare in the managed landscapes in Fennoscandia,causing significant habitat loss for saproxylic species such as polypores and *** better understand how the beetle community changes(species turnover)after a wildfire in a landscape with intense fire suppression,we monitored beetles with flight intercept traps the first 3 years as well as 12 years after a large wildfire in a national park in northern Sweden(a control/unburnt area was set up for the last year of sampling).Results:Species composition changed significantly among all studied years with a continuous turnover of species following the *** indicator species analysis showed that year 1 post-fire was mostly associated with cambium consumers and also the pyrophilous species Batrisodes *** 2 was the most abundant and species-rich year,with Tomicus piniperda as the most important indicator *** indicator species year 3 were mostly secondary successional species,fungivores,and predators and were characterized by lower species *** 12 had higher diversity compared with year 3 but lower species richness and abundance.A control area was established during year 12 post-fire,and our analyses showed that the control area and burned area differed in species composition suggesting that the beetle community needs longer than 12 years to recover even after a lowintensive ground ***:The wildfire area hosted several red-listed and fire-dependent species suggesting that after a century of landscape-level fire suppression in a semi-natural area,the reintroduction of fire benefits rare and pyrophilous species and still impacts species composition after 12 *** study implies that fire has long-lasting effects on high latitudes and that prescribed burning has the potential to benefit biodiversity over decades in these

关键词： Assemblage Boreal Coleoptera Species composition Conservation Disturbance Diversity Fire suppression Insects Protected area Saproxylic

Bayesian inference-based wear prediction method for plain bearings under stationary mixed-friction conditions

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Friction 2024年第6期12卷 1272-1282页

作者： Florian KÖNIG Florian WIRSING Georg jACOBS Rui HE Zhigang TIAN Ming j.ZUO Institute for Machine Elements and Systems Engineering RWTH Aachen UniversityAachen 52062Germany Department of Mechanical Engineering University of AlbertaEdmonton T6G1H9Canada Qingdao International Academician Park Research Institute Qingdao 266000China

This study introduces a method to predict the remaining useful life(rul)of plain bearings operating under stationary,wear-critical *** this method,the transient wear data of a coupled elastohydrodynamic lubrication(mixed-EHL)and wear simulation approach is used to parametrize a statistical,linear degradation *** method incorporates Bayesian inference to update the linear degradation model throughout the runtime and thereby consider the transient,system-dependent wear progression within the rul prediction.A case study is used to show the suitability of the proposed *** results show that the method can be applied to three distinct types of post-wearing-in behavior:wearing-in with subsequent hydrodynamic,stationary wear,and progressive wear *** hydrodynamic operation leads to an infinite lifetime,the method is successfully applied to predict rul in cases with stationary and progressive wear.

关键词： plain bearings wear modeling remaining useful life prediction Bayesian inference

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien G.Moreau jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

DeepRice: A deep learning and deep feature based classification of Rice leaf disease subtypes

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ARTIFICIAL INTELLIGENCE IN AGRICULTURE 2024年第1期11卷 34-49页

作者： Ritharson, P. Isaac Raimond, Kumudha Mary, X. Anitha Robert, jennifer Eunice Andrew, j. Karunya Inst Technol & Sci Dept CSE Coimbatore Tamilnadu India Karunya Inst Technol & Sci Dept Robot Engn Coimbatore India Manipal Acad Higher Educ Manipal Inst Technol Dept Mechatron Engn Manipal 576104 Karnataka India Manipal Acad Higher Educ Manipal Inst Technol Dept Comp Sci & Engn Manipal 576104 Karnataka India

Rice stands as a crucial staple food globally, with its enduring sustainability hinging on the prompt detection of rice leaf diseases. Hence, efficiently detecting diseases when they have already occurred holds paramount importance for solving the cost of manual visual identification and chemical testing. In the recent past, the identification of leaf pathologies in crops predominantly relies on manual methods using specialized equipment, which proves to be time-consuming and inefficient. This study offers a remedy by harnessing Deep Learning (DL) and transfer learning techniques to accurately identify and classify rice leaf diseases. A comprehensive dataset comprising 5932 self-generated images of rice leaves was assembled along with the benchmark datasets, categorized into 9 classes irrespective of the extent of disease spread across the leaves. These classes encompass diverse states including healthy leaves, mild and severe blight, mild and severe tungro, mild and severe blast, as well as mild and severe brown spot. Following meticulous manual labelling and dataset segmentation, which was validated by horticulture experts, data augmentation strategies were implemented to amplify the number of images. The datasets were subjected to evaluation using the proposed tailored Convolutional Neural Networks models. Their performance are scrutinized in conjunction with alternative transfer learning approaches like VGG16, Xception, ResNet50, DenseNet121, Inception ResnetV2, and Inception V3. The effectiveness of the proposed custom VGG16 model was gauged by its capacity to generalize to unseen images, yielding an exceptional accuracy of 99.94%, surpassing the benchmarks set by existing state-of-the-art models. Further, the layer wise feature extraction is also visualized as the interpretable AI. (c) 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-nd license (http://creativeco

关键词： Rice leaf disease Deep learning CNN Crop yield Agriculture Food security IDENTIFICATION

Population assessment and habitat associations of the Visayan Hornbill(Penelopides panini)in Northwest Panay,Philippines

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Avian Research 2021年第4期12卷 612-622页

作者： Holly Isabelle Mynott David Charles Lee Rhea Aranas Santillan Christian j.rgen Schwarz Benjamin Tacud Arcel Dryden Fernandez Daphne Kerhoas Bristol Zoological Society Bristol Zoo GardensCollege RoadCliftonBristol BS83HAUK School of Applied Sciences University of South WalesAlfred Russel Wallace BuildingUpper Glyntaff CampusPontypridd CF374BBUK PhilinCon L.A.Dioso Memorial Public LibraryIloilo-Antique Road5712 PandanPhilippines PhilinCon Germany Ruhr-Universität BochumUniversitätsstraße 150ND 1/3144801 BochumGermany

Background:Seven out of ten hornbill species in the Philippines are threatened with *** these is the endangered Visayan Hornbill(Penelopides panini),found on the islands of Panay and *** by habitat loss and hunting,its population size is thought to have declined from 1800 individuals 20 years ago to less than ***,a recent study on Negros estimated 3564 individuals across three core forest *** study aims to quantify the Visayan Hornbill population size in and around the Northwest Panay Peninsula Natural Park(NWPPNP)on Panay,the largest contiguous low-elevation forest landscape remaining across its range,and its broad habitat associations across a gradient of environmental ***:Hornbills were surveyed using 10-min distance sampling point counts(n=367)along transects(average length 1.1 km).Environmental variables were recorded along transects,while habitat was classified into primary forest,secondary forest,plantation,or open *** software was used to estimate population densities stratified by habitat,with the overall population estimate taken as a mean of habitat density estimates weighted by habitat *** generalized linear mixed models,hornbill occurrence was modelled using combinations of nine environmental variables as main and two-way fixed ***:Surveys covered 204.4 km^(2) of the 374.8 km^(2) Northwest Panay *** were not recorded in plantations or open *** density was significantly higher in primary forest(17.8 individuals/km~2±26.9%CV)than in secondary forest(3.7 individuals/km^(2)±33.2%CV;z=15.212,Pnd environs is 2109 individuals,and 2673 individuals for the entire Northwest Panay *** presence was best explained by a model including distance from the Park boundary alongside five interaction effects and transect as a random ***,and the interaction between distance

关键词： Distance sampling Endangered species GLMM Hornbill Point count Population size Protected area

Highly divergent sympatric lineages of Leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the Isthmus of Tehuantepec,Mexico

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Avian Research 2024年第1期15卷 12-21页

作者： Orlando j.Espinosa-Chávez Adolfo G.Navarro-Sigüenza Hernando Rodríguez-Correa Luis A.Sánchez-González Museo de Zoología“Alfonso L.Herrera” Depto.de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autonoma de MexicoApdo.Postal 70-399CP 04510Ciudad de MexicoMexico Posgrado en Ciencias Biologicas Unidad de PosgradoEdificio D1◦PisoCircuito de PosgradosCiudad UniversitariaUniversidad Nacional Autonoma de MexicoCoyoacanCP 04510CDMXMexico Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autonoma de Mexico.Antigua Carretera a Patzcuaro No.8701 Col.Ex Hacienda de San Jose de la HuertaC.P.58190MoreliaMichoacanMexico

Due to a complex geological and biotic history,the Isthmus of Tehuantepec(IT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland *** distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized *** of these have been recorded in Mexico,and the distribution of three abuts at the IT,suggesting a contact *** estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(nd2 and COI)and one n DNA(β-fibint 7)*** also used correlative ecological niche models(ENM)to assess whether ecological differences across the IT may have acted as a biogeographical *** estimated paleodistributions during the Middle Holocene,Last Glacial Maximum and Last Interglacial,to evaluate the influence of climate changes on the distribution and demographic *** results showed genetically distinct lineages that diverged approximately 2.5 million years *** and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern *** ecological niche comparisons indicated that the ecological niche of sympatric lineages at the IT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low *** results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological ***,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group.

关键词： Biogeographical boundary Humid and dry forests Isthmus of Tehuantepec Phylogeography Secondary contact

Soil Water Hysteresis at Low Potential

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Pedosphere 2007年第4期17卷 436-444页

作者： L.PRUNTY j.BELL Department of Soil Science North Dakota State University FargoND 58105 (USA)

Knowledge of the soil water characteristic curve is fundamental for understanding unsaturated *** objective of this work was to find scanning hysteresis loops of two fine textured soils at water potentials below wilting *** was done by equilibration over NaCl solutions with water potentials of-6.6 to-18.8 MPa at 25℃.When cycled repeatedly through a series of potentials in the range noted previously both soils exhibited a hysteresis *** experimental differences in water content between the drying and wetting soils at the same water potential were much too large to be accounted for by failure to allow sufficient time to attain equilibrium as predicted by the exponential decay *** wetting versus drying differences were relatively small,however,at only 4 mg g-1 or less in absolute terms and about 3% of the mean of wetting and drying,in relative *** should be a consideration when modeling biological and physical soil processes at water contents below the wilting point,where small differences in water content result in large potential energy changes.

关键词： adsorption dry soil equilibration matric potential soil water characteristic

Spin order and dynamics in the topological rare-earth germanide semimetals

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 113-127页

作者： Yuhao Wang Zhixuan Zhen jing Meng Igor Plokhikh Delong Wu Dariusz j.Gawryluk Yang Xu Qingfeng Zhan Ming Shi Ekaterina Pomjakushina Toni Shiroka Tian Shang Key Laboratory of Polar Materials and Devices(MOE) School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Laboratory for Multiscale Materials and Experiments Paul Scherrer InstitutVilligen PSI CH-5232Switzerland Center for Correlated Matter and School of Physics Zhejiang UniversityHangzhou 310058China Laboratory for Muon-Spin Spectroscopy Paul Scherrer InstitutVilligen PSI CH-5232Switzerland Laboratorium für Festkörperphysik ETH ZürichZürich CH-8093Switzerland

The REAl(Si,Ge)(RE=rare earth)family,known to break both the inversion-and time-reversal symmetries,represents one of the most suitable platforms for investigating the interplay between correlated-electron phenomena and topologically nontrivial ***,we report on systematic magnetic,transport,and muon-spin rotation and relaxation(μSR)measurements on(nd,Sm)AlGe single crystals,which exhibit antiferromagnetic(AFM)transitions at T_(N)=6.1 and 5.9 K,*** addition,ndAlGe undergoes also an incommensurate-to-commensurate ferrimagnetic transition at 4.5 *** transverse-fieldμSR measurements confirm the AFM transitions,featuring a~90%magnetic volume ***-field(ZF)μSR measurements reveal a more disordered internal field distribution in ndAlGe than in SmAlGe,reflected in a larger transverse muon-spin relaxation rateλTat TndAlGe,which undergoes a series of metamagnetic transitions in an external magnetic field,while SmAlGe shows only a robust AFM *** ndAlGe,the topological Hall effect(THE)appears between the first and the second metamagnetic transitions for H‖c,while it is absent in *** THE in ndAlGe is most likely attributed to the field-induced topological spin *** longitudinal muon-spin relaxation rateλL,diverges near the AFM order,followed by a clear drop at TndAlGe than in *** general,our longitudinal-fieldμSR data indicate vigorous spin fluctuations in ndAlGe,thus providing valuable insights into the origin of THE and of the possible topological spin textures in REAl(Si,Ge)Weyl semimetals.

关键词： magneticWeyl semimetals topological Hall effect spin fluctuations μSR

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Transepithelial transport of putrescine across monolayers of the human intestinal epithelial cell line, Caco-2

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World journal of Gastroenterology 2001年第2期7卷 193-197页

作者： Vladan Milovic Lyudmila Turchanowa j.rgen Stein Wolfgang F.Caspary 2nd Department of Medicine Johann Wolfgang Goethe UniversityFrankfurtGermany

AIM: To study the transepithelial transport characteristics of the polyamine putrescine in human intestinal Caco-2 cell monolayers to elucidate the mechanisms of the putrescine intestinal absorption. METHODS: The transepithelial transport and the cellular accumulation of putrescine was measured using Caco-2 cell monolayers grown on permeable filters. RESULTS: Transepithelial transport of putrescine in physiological concentrations (> 0.5 mM) from the apical to basolateral side was linear. Intracellular accumulation of putrescine was higher in confluent than in fully differentiated Caco-2 cells, but still negligible (less than 0.5%) of the overall transport across the monolayers in apical to basolateral *** enhanced putrescine accumulation in Caco-2 cells by four fold, as well as putrescine conversion to spermidine and spermine by enhancing the activity of S adenosylmethionine decarboxylase. However, EGF did not have any significant influence on putrescine flux across the Caco-2 cell monolayers. Excretion of putrescine from Caco-2 cells into the basolateral medium did not exceed 50 picomoles, while putrescine passive flux from the apical to the basolateral chamber, contributed hundreds of micromoles polyamines to the basolateral chamber. CONCLUSION :Transepithelial transport of putrescine across Caco2 cell monolayers occurs in passive diffusion, and is not influenced when epithelial cells are stimulated to proliferate by a potent mitogen such as EGF.

关键词： Biological Transport Caco-2 Cells Epidermal Growth Factor Humans Intestinal Absorption Putrescine Recombinant Proteins Research Support, Non-U.S. Gov't