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Diet composition of the lizard P odarcis lilfordi (Lacertidae) on 2 small islands: an individualresource network approach

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Current Zoology 2020年第1期66卷 39-49页

作者： Silvia SANTAmARIA Camilla Aviaaja ENOKSEN jens m.olesen Giacomo TAVECCHIA Andreu ROTGER Jose manuel IGUAL Anna TRAVESET Global Change Research Group Inst.Mediterrani d'Estudis Avanqats(CSIC-UIB)C/Miquel Marques 21E07190 EsporlesMallorcaBalearic IslandsSpain Section for Ecoinformatics&Biodiversity Department of BioscienceAarhus UniversityAarhus C8000Denmark Animal Ecology and Demography Group Inst.Mediterrani d'Estudis Avanqats(CSIC-UIB)C/Miquel Marques 21EsporlesMallorcaBalearic IslandsE07190Spain

Despite it is widely accepted that intrapopulation variation is fundamental to ecological and evolutionary processes,this level of information has only recently been included into network analysis of species/population *** done,it has revealed non-random patterns in the distribution of trophic *** in resource use among individuals is the most recurrent observed pattern,often accompanied by an absence of modularity,but no previous studies examine bipartite *** use network analysis to describe the diet composition of the Balearic endemic lizard Podarcis lilfordi in 2 islets at population and individual levels,based on the occurrence of food items in fecal *** objectives are to 1)compare niche structure at both levels,2)characterize niche partition using nestedness and modularity,and 3)assess how size,sex,season,and spatial location influence niche *** population-level niche width was wide,but narrow at the level of the *** islet networks were nested,indicating similar ranking of the food preferences among individuals,but also modular,which was partially explained by *** and body size did not notably affect diet *** niche overlap and therefore possibly relaxed competition were observed among females in one of the islets and during spring on both ***,higher modularity in autumn suggests that higher competition could lead to specialization in both populations,because resources are usually scarce in this *** absence of spatial location influence on niche might respond to fine-grained spatio-temporally distribution of food *** traits,not included in this study,could also influence resource partitioning.

关键词： Balearic Islands individual diet composition individual-level network modularity nestedness population niche width

Pin-on-disc tribological characterization of single ingredients used in a brake pad friction material

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Friction 2024年第11期12卷 2576-2593页

作者： Davide CARLEVARIS Francesco VARRIALE jens WAHLSTRÖm Cinzia mENAPACE Department of Industrial Engineering University of TrentoTrento 38123Italy Brembo S.p.A StezzanoBergamo 24040Italy Department of mechanical Engineering Sciences Lund UniversityLund 22100Sweden

Researchers have long been studying the effects of the modification of friction material compositions on their tribological *** models have also been developed,but they are of limited use in the design of new ***,this research aims to investigate the tribological behaviour of single ingredients in friction materials to develop a tribological *** dataset could then be used as a foundation for a cellular automaton(CA)predictive model,intended to be a tool for designing friction *** samples were almost entirely composed of four distinct friction material ingredients,and one sample composed of their mixture was successfully ***-on-disc(PoD)tribometer testing and scanning electron microscopy/energy-dispersive X-ray spectroscopy(SEm/EDXS)analysis were used for the tribological *** material showed distinct tribological properties and evolution of the contact surface features,and the synergistic effect of their mutual interaction was also demonstrated by their mixture.

关键词： disc brakes sliding contact wear behaviour scanning electron microscopy(SEm) modelling

Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： jens müller Sebastian Leonow Johannes Schulz Christian Hansen martin monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

Developing fertility control for rodents: a framework for researchers and practitioners

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Integrative Zoology 2024年第1期19卷 87-107页

作者： Giovanna mASSEI jens JACOB Lyn A.HINDS Botstiber Institute for Wildlife Fertility Control Department of Environment and GeographyUniversity of YorkHeslingtonYorkUK Rodent Research Institute for Epidemiology and Pathogen DiagnosticsJulius Kühn–Institute(JKI)Federal Research Institute for Cultivated PlantsMünsterGermany CSIRO Health and Biosecurity CanberraACTAustralia

Fertility control is often heralded as a humane and effective technique for management of overabundant wildlife,including *** intention is to reduce the use of lethal and inhumane methods,increase farm productivity and food security as well as reduce disease transmission,particularly of *** developed a framework to guide researchers and stakeholders planning to assess the effectiveness of a potential contraceptive agent for a particular *** guidelines describe the overarching research questions which must be sequentially addressed to ensure adequate data are collected so that a contraceptive can be registered for use in broad-scale rodent *** framework indicates that studies should be undertaken iteratively and,at times,in parallel,with initial research being conducted on(1)laboratory-based captive assessments of contraceptive effects in individuals;(2)simulation of contraceptive delivery using bait markers and/or surgical sterilization of different proportions of afield-based or enclosure population to determine how population dynamics are affected;(3)development of mathematical models which predict the outcomes of different fertility control scenarios;and(4)implementation of large-scale,replicated trials to validate contraceptive efficacy under various management-scalefield *** some circumstances,fertility control may be most effective when integrated with other methods(*** culling).Assessment of non-target effects,direct and indirect,and the environmental fate of the contraceptive must also be *** fertility control for a species is a resource-intensive commitment but will likely be less costly than the ongoing environmental and economic impacts by rodents and rodenticides in many contexts.

关键词： captive studies field applications modeling oral contraceptive delivery population management rodents

metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar m.Patel Oseeyi I.Daudu Donald F.Becker Jonathan L.Robinson jens Nielsen Department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Small mammal community composition impacts bank vole (Clethrionomys glareolus) population dynamics and associated seroprevalence of Puumala orthohantavirus

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Integrative Zoology 2024年第1期19卷 52-65页

作者： Felicitas maria BUJNOCH Daniela REIL Stephan DREWES Ulrike mROSENFELD Rainer G.ULRICH jens JACOB Christian ImHOLT Julius Kühn-Institute Federal Research Centre for Cultivated PlantsInstitute for Epidemiology and Pathogen DiagnosticsRodent ResearchMünsterGermany University of münster Institute for Evolution and BiodiversityMünsterGermany Friedrich-Loeffler-Institut Federal Research Institute for Animal HealthInstitute of Novel and Emerging Infectious DiseasesGreifswald-Insel RiemsGermany

Rodents are important reservoirs for zoonotic pathogens that cause diseases in *** is hypoth-esized to be closely related to pathogen prevalence through multiple direct and indirect *** example,the presence of non-host species can reduce contact rates of the main reservoir host and thus reduce the risk of transmission(“dilution effect”).In addition,an overlap in ecological niches between two species could lead to increased interspecific competition,potentially limiting host densities and reducing density-dependent pathogen transmission *** this study,we investigated the relative impact of population-level regulation of direct and indirect drivers of the prevalence of Puumala orthohantavirus(PUUV)in bank voles(Clethrionomys glareolus)during years with high *** compiled data on small mammal community composition from four regions in Germany between 2010 and *** equation modeling revealed a strong seasonality in PUUV control mechanisms in bank *** abundance of shrews tended to have a negative relationship with host abundance,and host abundance positively influenced PUUV seroprevalence,while at the same time increasing the abundance of competing non-hosts like the wood mouse(Apodemus sylvaticus)and the yellow-neckedfield mouse(Apodemusflavicollis)were associated with reduced PUUV seroprevalence in the *** results indicate that for PUUV in bank voles,dilution is associated with increased interspecific *** pressures leading to the decline of Apodemus *** a specific habitat could lead to the amplification of mechanisms promoting PUUV transmission within the host populations.

关键词： bank vole biodiversity Puumala orthohantavirus small mammals

Wind farms increase land surface temperature and reduce vegetation productivity in the Inner mongolia

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Geography and Sustainability 2024年第3期5卷 319-328页

作者： Luyao Liu Pengtao Liu Jiawei Yu Gang Feng Qing Zhang jens-Christian Svenning ministry of Education Key Laboratory of Ecology and Resource Use of the mongolian Plateau School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Key Laboratory of Forest Ecology and management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Inner mongolia Autonomous Region Ecological and Agricultural meteorological Centre Hohhot 010051China e Collaborative Innovation Center for Grassland Ecological Security(Jointly Supported by the ministry of Education of China and Inner mongolia Autonomous Region) Hohhot 010021China Center for Ecological Dynamics in a Novel Biosphere(ECONOVO) Department of BiologyAarhus UniversityNy Munkegade 114Aarhus C DK-8000Denmark Center for Biodiversity Dynamics in a Changing World(BIOCHANGE) Department of BiologyAarhus UniversityNy Munkegade 114Aarhus C DK-8000Denmark

Wind power has been developing rapidly as a key measure to mitigate human-driven global *** under-standing of the development and impacts of wind farms on local climate and vegetation is of great importance for their rational use but is still *** this study,we combined remote sensing and on-site investigations to identify wind farm locations in Inner mongolia and performed landscape pattern analyses using *** explored the impacts of wind farms on land surface temperature(LST)and vegetation net primary productivity(NPP)between 1990 and 2020 by contrasting these metrics in wind farms with those in non-wind farm *** results showed that the area of wind farms increased rapidly from 1.2 km2 in 1990 to 10,755 km2 in ***,wind farms are mainly clustered in three aggregation areas in the ***,wind farms increased nighttime LST,with a mean value of 0.23℃,but had minor impacts on the daytime ***,wind farms caused a decline in NPP,especially over forest areas,with an average reduction of 12.37 GC/m^(2).Given the impact of wind farms on LST and NPP,we suggest that the development of wind farms should fully consider their direct and potential *** study provides scientific guidance on the spatial pattern of future wind farms.

关键词： Wind farm Landscape pattern LST NPP Inner mongolia

Steroidal scaffold decorations in Solanum alkaloid biosynthesis

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molecular Plant 2024年第8期17卷 1236-1254页

作者： Rosalind Lucier mohamed O.Kamileen Yoko Nakamura Sofiia Serediuk Ranjit Barbole jens Wurlitzer maritta Kunert Sarah Heinicke Sarah E.O'Connor Prashant D.Sonawane Department of Natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany Research Group Biosynthesis and NmR Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences Division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in Nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galapagos lava lizards

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Current Zoology 2019年第4期65卷 353-361页

作者： Sandra HERVIAS-PAREJO Ruben HELENO Beatriz RUmEU Beatriz GUZmAN Pablo VARGAS jens m. olesen Anna TRAVESET Carlos VERA Edgar BENAVIDES manuel NOGALES Institut mediterrani d'Estudis Avanqats (CSIC-UIB) Global Change Research Group Mallorca Balearic Islands Spain Centre for Functional Ecology Department of Life Sciences University of Coimbra Portugal Real Jardin Botanico (CSIC-RJB) Madrid Spain Department of Bioscience Aarhus University Denmark Galapagos National Park Puerto Ayora Santa Cruz Galapagos Ecuador Department of Ecology and Evolutionary Biology Yale University USA lnstituto de Productos Naturales Agrobiologia (CSIC-IPNA) Island Ecology and Evolution Research Group Canary Islands Spain

Frugivory in lizards is often assumed to be constrained by body size;only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (microlophus spp.) were studied on the eleven largest Galapagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abunda nee in flue nces fruit con sumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snoutvent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more importa nt drivers of fruit selecti on (e.g., fruit size, energy con tent of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galapagos. most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizardingested seeds compared to control (uningested) fruits. De-pulping by lizards (i.e., removal of pulp with potential germi nation inhibitors) might in crease the chances that at least some seeds find suitable recruitment conditi ons. We con eluded that lizards are importa nt seed dispersers throughout the year and across the whole archipelago, regardless of body size.

关键词： microlophus oceanic islands plant-animal interactions seed disperser size seed dispersal effectiveness seedling emergence