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Seasonal variation and host sex affect bat–bat fly interaction networks in the Amazonian savannahs

Integrative Zoology 2024年第3期19卷 400-416页

作者： Paulo MEJIA Gustavo Lima URBIETA Bruna da Silva XAVIER IsaíJorge de CASTRO JoséJúlio DE TOLEDO Gustavo GRACIOLLI Lucio andréVIANA DIAS William Douglas CARVALHO Programa de Pós-Graduação em Biodiversidade Tropical Universidade Federal do Amapá(UNIFAP)MacapáAPBrazil Programa de Pós-Graduação em Ecologia Instituto de BiologiaCentro de Ciências da SaúdeUniversidade Federal do Rio de Janeiro(UFRJ)Rio de JaneiroRJBrazil Laboratório de Mamíferos Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá(IEPA)MacapáAPBrazil Programa de Pós-Graduação em Biologia Animal Laboratório de SistemáticaEcologia e Evolução(LSEE)Instituto de BiociênciasUniversidade Federal de Mato Grosso do Sul(UFMS)Campo GrandeMTBrazil Terrestrial Ecology Group(TEG-UAM) Departamento de EcologíaFacultad de CienciasUniversidad Autónoma de MadridMadridSpain Centro de Investigación en Biodiversidad y Cambio Global(CIBC-UAM) Universidad Autónoma de MadridMadridSpain

Bats are the second-most diverse group of mammals in the world,and bat flies are their main ***,significant knowledge gaps remain regarding these antagonistic interactions,especially since diverse factors such as seasonality and host sex can affect their network ***,we explore the influence of such factors by comparing species richness and composition of bat flies on host bats,as well as specialization and modularity of bat–bat fly interaction networks between seasons and adult host *** captured bats and collected their ectoparasitic flies at 10 sampling sites in the savannahs of AmapáState,northeastern region of the Brazilian *** female bats being more parasitized and recording greater bat fly species richness in the wet season,neither relationship was statistically *** pooled network could be divided into 15 compartments with 54 links,and all subnetworks comprised>12 *** total number of links ranged from 27 to 48(for the dry and wet seasons,respectively),and female and male subnetworks had 44 and 41 links,*** values were very low for the pooled network and for all *** results revealed higher bat fly species richness and abundance in the wet season,whereas specialization and modularity were higher in the dry ***,the subnetwork for female bats displayed higher specialization and modularity than the male ***,both seasonality and host sex contribute in different ways to bat–bat fly network *** studies should consider these factors when evaluating bat–bat fly interaction networks.

关键词： Amapá Amazon biome bat flies bats interaction networks

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Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China

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Journal of Arid Land 2014年第4期6卷 423-431页

作者： YongQing LUO XueYong ZHAO Olof andréN YangChun ZHU WenDa HUANG Naiman Desertification and Farmland Research Station of the Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences Bjorklundavagen 3

Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon（C） contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid（0.6 g C/kg dry soil） were added to soils from three biotopes（grassland, fixed dune and mobile dune） located in Naiman, Horqin Sandy Land, Inner Mongolia, China） and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration（including that from the added substrates） was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical condu

关键词： artificial root exudates carbon mineralization pH variation deteriorated grassland ecosystem Inner Mongolia

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高压条件下块体碳纳米管的制备(英文)

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新型炭材料 2014年第3期29卷 193-202页

作者： Pamela andréa Mantey dos Santos Аrea de Ciências Tecnológicas Centro Universitário Franciscano UNIFRA Santa Maria 97010-032 RS Brasil Instituto de Química Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil) Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil) Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil) Instituto de Ffsica Universidade Federal do Rio Grande do Sul UFRGS Porto Alegre 91501-970 RS Brasil

分别以高纯碳纳米管(MWCNTs)、未纯化MWCNTs和盐酸纯化MWCNTs为原料,铅(Pb)和石墨(Gr)为压力传递媒介,在4GPa和7.7GPa高压和室温条件下制备块体碳纳米管。其直径约为6nm,呈圆柱形块体。采用拉曼光谱仪、X-射线衍射仪、氮吸附仪和透射电... 详细信息

分别以高纯碳纳米管(MWCNTs)、未纯化MWCNTs和盐酸纯化MWCNTs为原料,铅(Pb)和石墨(Gr)为压力传递媒介,在4GPa和7.7GPa高压和室温条件下制备块体碳纳米管。其直径约为6nm,呈圆柱形块体。采用拉曼光谱仪、X-射线衍射仪、氮吸附仪和透射电镜表征样品。结果表明,含有MgO催化剂杂质的未纯化MWCNTs,以Pb为媒介时,在7.7GPa下可获得最佳压缩样品。高压可引起MWCNTs压缩和剪切应力。Pb容器作为准静压传递媒介可提供更多压缩应力,同时杂质能作为黏结剂,从而有利于得到致密化度较高的MWCNTs。

关键词：碳纳米管高压块体碳纳米管拉曼光谱透射电镜

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Formation of a 40 A DC Current Arc During the Opening of Silver Contacts

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Plasma Science and Technology 2014年第5期16卷 471-478页

作者： M'hammed ABBAOUI andré LEFORT Erwann CARVOU Damien SALLAIS James Brian Alexander MITCHELL Noureddine BEN JEMAA Clermont Université Université d'AuvergneEA 3120LAEPTBP 10448F-63000 Clermont-FerrandFrance Equipe Contacts Electriques IPR(UMR CNRS 6251)Universite de Rennes 135042 Rennes CedexFrance

The erosion of silver contacts due to break arcs with length proportional to time and of variable duration has been measured by weighing the contacts following 5000 openings at a constant current equal to 40 *** experimental results show that,for arc durations shorter than 60 μs,the transfer of metal from the anode to the cathode occurs,but after passing this stage,when the two electrodes are separated by greater distances,each will display *** is the result of the diffusion of material outside the space between the two *** order to interpret these results,we have applied a classical model of the physical phenomena occurring at the root of the *** of the experimental results shows that for an arc duration of less than15 μs,no distinct cathode root is seen to exist,but beyond this,several spots appear gradually on the cathode for arc duration up to 50 μs,after which they merge into a single *** comparison between experiment results and theoretical interpretation is reasonable up to 60 μs.

关键词： arc root cathode spot anode spot erosion contacts current density

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Do Aqueous Extracts from Buckwheat Compromise Seed Germination and Initial Development of Bidens pilosa and Euphorbia heterophylla?

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Agricultural Sciences 2023年第6期14卷 804-818页

作者： Joanei Cechin Mateus Poncheki andré Belmont Pereira João Victor de Mattos Rafael Domingues Department of Crop Science Syngenta Seeds Cascavel PR Brazil Department of Crop Science & Plant Protection State University of Ponta Grossa Ponta Grossa PR Brazil Department of Soil Science & Agricultural Engineering State University of Ponta Grossa Ponta Grossa PR Brazil Department of Plant Nutrition& Soil Science Nutrien Agri-Solutions S&#227o Paulo SP Brazil Institute of Agricultural Sciences & Technology State University of Ponta Grossa Ponta Grossa PR Brazil

Fagopyrum esculentum Moench (buckwheat) is a dicot species from the Polygonaceae family used as a cover crop in agricultural systems featured with a remarkable allelopathic potential for weed control, helping herbicide-resistance management and promoting substantial reductions in herbicide applications. The aim of this research was to examine the allelopathic potential of aqueous extracts from seeds and aerial part of buckwheat on seed germination and initial development of Bidens pilosa and Euphorbia heterophylla. Bioassay experiments were conducted under a completely randomized experimental design with four replications, containing 50 seeds each. Both weed seed species were harvested in a soybean field, and seed viability was previously assessed. Seeds were exposed to four concentrations (0, 25, 50, and 100%) from extracts of seeds (ES) and aerial part (Eap) of buckwheat. Germination speed index (GSI) in B. pilosa and E. heterophylla was daily evaluated throughout 14 and 16 days, respectively, whereas percentage of germination, abnormal seedlings, as well as non-germinated seeds, root (RL) and aerial part length (apL), and total dry matter (TDM) were rated at final germination test. Eap reduced the GSI, especially under the 100% concentration. Germination percentage was lower and abnormal seedlings increased for both weed species when seeds were exposed to Eap concentrations greater than 25%. However, ES did not impinge upon E. heterophylla germination. Eap and ES reduced the apL, RL, and TDM for concentrations greater than 50%, except for ES which did not affect E. heterophylla development. Both extracts from buckwheat have a high capacity to inhibit germination and compromise seedling development, culminating in such a potential alternative for B. pilosa and E. heterophylla management in agricultural systems.

关键词： Fagopyrum esculentum Moench Plant Allelopathy Allelochemicals Weed Management Bioherbicides

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Understanding bark thickness variations for Araucaria angustifolia in southern Brazil

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Journal of Forestry Research 2021年第3期32卷 1077-1087页

作者： Emanuel Arnoni Costa Veraldo Liesenberg César Augusto Guimaraes Finger andréFelipe Hess Cristine Tagliapietra Schons Graduate Program in Forest Engineering Santa Catarina State University(UDESC)LagesSC 88520-000Brazil Department of Forest Engineering Federal University of Uberlandia(UFU)Monte CarmeloMG 38500-000Brazil Graduate Program in Forest Engineering Federal University of Santa Maria(UFSM)Santa MariaRS 97105-900Brazil Graduate Program in Agroecosystems Federal Technological University of Parana(UFTPR)Dois VizinhosPR 85660-000Brazil

This study aimed to understand bark thickness variations of Araucaria angustifolia(Bertol.)Kuntze trees growing in natural forest remnants in southern Brazil,and their relationship with quantitative and qualitative *** thickness must be accurately estimated in order to determine timber volume *** is an important variable for the sustainable management and conservation of araucaria *** spite of its importance and visibility,bark thickness variations have not been evaluated for this key species in southern Brazil.A total of 104 trees were selected,and their qualitative and quantitative attributes such as diameter at breast height(D_(BH)),height(H),crown base height(C_(BH)),crown length(C_(L)),social position(S_(P)),stoniness(S_(T)),position on the relief(P_(R)),vitality(V_T)and branch arrangement(B_(A))were *** trees were categorized into two groups:red bark or gray *** analysis and artificial neural networks(ANN)were used for modelling bark *** results indicate that:(1)bark thickness showed good correlation to D_(BH),with 0.76 as coefficient of determination(RS_P),0.540 as Mean Absolute Error(M_(AE))and 22.4 root-meansquare error in percentage(R_(MSE%));(2)the trend changed according to bark colour,with significant differences for the intersection(_0–Pr>F:p=0.0124)and slope(β_(1)–Pr>F:p=0.0126)of bark thickness curves between groups;(3)the highest correlation of bark thickness was found with:D_(BH)(ρ=0.88),H(ρ=0.58),C_(BH)(ρ=0.46),S_(P)(ρ=-0.52),and B_(A)(ρ=-0.32);(4)modelling with ANN confirmed high adjustment(R^(2)=0.99)and accuracy(R_(MSE%)=3.0)of the *** is an efficient and robust technique for the modelling of various qualitative and quantitative attributes commonly used in forest *** effective use of ANN to estimate araucaria bark in natural forests reinforces its potential,besides the possibility of application for other forest species.

关键词： Dendrometry attributes Crown characteristics Prediction models Bark factor Parana-pine

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Polyethylene glycol 35 ameliorates pancreatic inflammatory response in cerulein-induced acute pancreatitis in rats

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World Journal of Gastroenterology 2020年第39期26卷 5970-5982页

作者： Ana Ferrero-andrés Arnau Panisello-Roselló Joan Roselló-Catafau Emma Folch-Puy Experimental Pathology Department Institut d'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones científicasBarcelona 08036CataloniaSpain Experimental Pathology Department Institut d'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones científicasCentro de Investigación Biomédica en Red de Enfermedades Hepáticas y DigestivasInstitut d'Investigacions Biomèdiques August Pi i SunyerBarcelona 08036CataloniaSpain

BACKGROUND Acute pancreatitis(ap)is a sudden inflammatory process of the pancreas that may also involve surrounding tissues and/or remote *** and parenchymal cell death are common pathological features of this condition and determinants of disease *** glycols(PEGs)are nonimmunogenic,non-toxic water-soluble polymers widely used in biological,chemical,clinical and pharmaceutical *** To evaluate the protective effect of a 35-kDa molecular weight PEG(PEG35)on the pancreatic damage associated to cerulein-induced acute pancreatitis in vivo and in *** Wistar rats were assigned at random to a control group,a cerulein–induced ap group and a PEG35 treatment *** was induced by five hourly intraperitoneal injections of cerulein(50μg/kg/bw),while the control animals received saline ***35 was administered intraperitoneally 10 minutes before each cerulein injection in a dose of 10 mg/*** ap induction,samples of pancreatic tissue and blood were collected for ***42J pancreatic acinar cells were treated with increasing concentrations of PEG35 prior to exposure with tumor necrosis factorα(TNFα),staurosporine or *** severity of ap was determined on the basis of plasma levels of lipase,lactate dehydrogenase activity,pancreatic edema and histological *** evaluate the extent of the inflammatory response,the gene expression of inflammation-associated markers was determined in the pancreas and in AR42J-treated ***-induced cell death was also measured in models of in vivo and in vitro pancreatic *** Administration of PEG35 significantly improved pancreatic damage through reduction on lipase levels and tissue edema in cerulein-induced ap *** increased associated inflammatory response caused by cerulein administration was attenuated by a decrease in the gene expression of inflammation-related cytokines and inducible nitric oxide synthase enzyme in the *** contr

关键词： Acute pancreatitis Inflammation Polyethylene glycols Cytokines AR42J cells Cell death

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Atacama Field Campaign: laboratory and in-situ measurements for remote sensing applications

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International Journal of Digital Earth 2019年第1期12卷 43-61页

作者： Cristian Mattar andrés Santamaría-Artigas Flavio Ponzoni Cibele T.Pinto Carolina Barrientos Glynn Hulley Laboratory for Analysis of the Biosphere(LAB) University of ChileSantiagoChile Department of Geographical Sciences University of MarylandCollege ParkMDUSA Divisão de Sensoriamento Remoto(DSR) Instituto Nacional de Pesquisas Espaciais(INPE)São PauloBrasil Aerial Photogrammetric Service(SAF) Chilean Air ForceSantiagoChile Jet Propulsion Laboratory(JPL) California Institute of TechnologyPasadenaCAUSA

This work presents the preliminary results of the first field calibration campaign performed in the Atacama Desert,Chile,between the 18 and 22 August 2014,called the Atacama Field Campaign(ATAFIC 2014).In situ measurements were performed in order to spectrally characterize the surface reflectance spectra between 0.3 and 2.5μm,radiometric temperature(8.0–14.0μm)and atmospheric measurements.A soil sample was collected and analyzed using Fourier Transform Infrared Spectroscopy and X-Ray Diffraction techniques to characterize the surface reflectance spectra and mineralogical composition,*** land surface emissivity in addition to GOES,MODIS and Landsat-8 land surface temperature(LST)were also *** showed that the spectral features of the Atacama soil and the characteristics of this geographical zone,which is featured as the most hyper-arid and cloudless place in the world,make this area a potential target for surface reflectance *** and night LST comparison between field and remote sensing data are lower than 2 K and the root Mean Square Error for land surface emissivity is close to 2%.This work opens the possibilities to consider the Atacama Desert as a reference target for calibration and validation activities for earth observation missions’purposes.

关键词： Atacama spectroradiometry emissivity temperature surface reflectance

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Exotic tree seedlings are much more competitive than natives but show underyielding when growing together

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Journal of Plant Ecology 2013年第4期6卷 305-315页

作者： Heike Kawaletz Inga Mölder Stefan Zerbe Peter Annighöfer andré Terwei Christian Ammer Department of Silviculture and Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Energieagentur Region Göttingen e.V. Berliner Str.237073 GöttingenGermany Faculty of Science and Technology Free University of Bozen-BolzanoPiazza Università539100 BolzanoItaly

Aims Invasive species continue to be a worldwide threat to ecosystems mainly as a cause for biodiversity *** ecosystems,for example,are subject to a change in species composition due to the invasion of exotic *** the attributes that cause the strong competitiveness of several exotic species may improve the ability to understand and effectively manage plant invasions in the *** this study the following hypotheses were tested:(1)biomass production of below-and aboveground plant compo-nents of the exotic tree species is higher than that of the natives,resulting in a higher competitiveness of the exotics;(2)the exclu-sion of root competition has a positive effect on the biomass pro-duction of the inferior native species;and(3)mixtures of native and exotic species yield a higher biomass production than the respective *** a pot experiment,containing about 2000 tree seedlings,was *** investigated the biomass productivity and growth reactions of two native(Quercus robur l.,Carpinus betulus l.)and two exotic tree species(Prunus serotina Ehrh.,Robinia pseudoacacia l.)in different intra-and interspecific,competitive situations with and without the influence of root *** Findingsthe biomass production of both exotic species was significantly higher and led to a strong competitive advantage,resulting in a biomass decrease of the less competitive native *** high belowground biomass of both exotic species had a negative effect on the biomass *** competitive pressure of exotic tree seedlings on the native ones was largely driven by root ***,mixtures of native and exotic tree species had a higher productivity than their growth in monocultures would have *** was lower for exotic species in mixtures with the less productive native species compared to the competition in monocultures or in mixture with the other highly productive exotic ***,b

关键词： competition biomass production pot experiment invasive species Prunus serotina Robinia pseudoacacia

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Mapping aboveground biomass and its prediction uncertainty using LiDAR and field data, accounting for tree-level allometric and LiDAR model errors

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Forest Ecosystems 2020年第3期7卷 562-578页

作者： Svetlana Saarela andréWästlund Emma Holmström Alex appiah Mensah Sören Holm Mats Nilsson Jonas Fridman Göran Ståhl Faculty of Forest Sciences Swedish University of Agricultural SciencesSLU Skogsmarksgränd 17UmeåSE-90183Sweden

Background: The increasing availability of remotely sensed data has recently challenged the traditional way of performing forest inventories, and induced an interest in model-based inference. Like traditional design-based inference, model-based inference allows for regional estimates of totals and means, but in addition for wall-to-wall mapping of forest characteristics. Recently Light Detection and Ranging(LiDAR)-based maps of forest attributes have been developed in many countries and been well received by users due to their accurate spatial representation of forest resources. However, the correspondence between such mapping and model-based inference is seldom appreciated. In this study we applied hierarchical model-based inference to produce aboveground biomass maps as well as maps of the corresponding prediction uncertainties with the same spatial resolution. Further, an estimator of mean biomass at regional level, and its uncertainty, was developed to demonstrate how mapping and regional level assessment can be combined within the framework of model-based ***: Through a new version of hierarchical model-based estimation, allowing models to be nonlinear, we accounted for uncertainties in both the individual tree-level biomass models and the models linking plot level biomass predictions with LiDAR metrics. In a 5005 km2 large study area in south-central Sweden the predicted aboveground biomass at the level of 18 m×18 m map units was found to range between 9 and 447 Mg·ha^-1. The corresponding root mean square errors ranged between 10 and 162 Mg·ha^-1. For the entire study region, the mean aboveground biomass was 55 Mg·ha^-1 and the corresponding relative root mean square error 8%. At this level 75%of the mean square error was due to the uncertainty associated with tree-level ***: Through the proposed method it is possible to link mapping and estimation within the framework of model-based inference. Uncertainties in both tree-level bio

关键词： Aboveground biomass assessment Forest mapping Gauss-Newton Regression Hierarchical Model-Based inference LiDAR maps National Forest Inventory Uncertainty estimation Uncertainty map

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