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Climate refugia along Lake Superior’s shores:disjunct arctic-alpine plants rely on cool shoreline temperatures but are restricted to highly exposed habitat under climate warming

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Journal of Plant Ecology 2024年第4期17卷 23-41页

作者： Ashley Hillman Scott E.nielsen Department of Renewable Resources University of AlbertaEdmontonAB T6G 2R3Canada

Climate refugia can serve as a remnant habitat or stepping stones for species dispersal under climate *** largest freshwater lake by surface area,Lake Superior,USA and Canada,serves as a model system for understanding cooling-mediated local refugia,as its cool water temperatures and wave action have maintained shoreline habitats suitable for southern disjunct populations of arctic-alpine plants since ***,we seek to explain spatial patterns and environmental drivers of arctic-alpine plant refugia along Lake Superior’s shores,and assess future risk to refugia under moderate(+3.5℃)and warmest(+5.7℃)climate warming ***,we examined how the interactive effects of summer surface water temperatures and wind affected onshore temperatures,resulting in areas of cooler ***,we developed an ecological niche model for the presence of disjunct arctic-alpine refugia(pooling 1253 occurrences from 58 species)along the lake’s ***,we fit species distribution models for 20 of the most common arctic-alpine disjunct species and predicted presence to identify refugia ***,we used the two climate warming scenarios to predict changes in the presence of refugia and disjunct *** type,elevation above water,inland distance,July land surface temperature from MoDIS/Terra satellite and near-shore depth of water were the best predictors of disjunct ***,we predicted 2236 km of the shoreline(51%)as disjunct refugia habitat for at least one species under current conditions,but this was reduced to 20% and 7% with moderate(894 km)and warmest(313 km)climate change projections.

关键词： climate refugia disjunct populations lake effect Lake Superior species distribution models

Transmission matrices used in epidemiologic modelling

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Infectious Disease Modelling 2024年第1期9卷 185-194页

作者： M.Bekker-nielsen Dunbar Centre for Research on Pandemics&Society OsloMet–Oslo Metropolitan UniversityHG536Holbergs gate 1Oslo0166Norway

Mixing matrices are included in infectious disease models to reflect transmission opportunities between population *** matrices were originally constructed on the basis of theoretical considerations and most of the early work in this area originates from research on sexually transferred diseases in the 80s,in response to *** work in the 90s populated these matrices on the basis of survey data gathered to capture transmission risks for respiratory *** provide an overview of developments in the construction of matrices for capturing transmission opportunities in *** transmission matrices are useful for epidemiologic modelling to capture within and between stratum transmission and can be informed from theoretical mixing assumptions,informed by empirical evidence gathered through investigation as well as generated on the basis of *** to summary measures and threshold conditions are also provided.

关键词： Disease transmission Mixing matrix Social contact Index of disassortativity

使用AI自动生成的胸片报告：临床影响的评估

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国际医学放射学杂志 2023年第4期 480-480页

作者： L.L.Plesner F.C.Müller J.D.Nybing L.C.Laustrup F.Rasmussen o.w.nielsen 刘晴

摘要正常胸片的自动解读可以减轻放射科医生的工作量。然而，与临床影像报告相比，这种人工智能（AI）软件的效能尚未确定。目的对商用AI软件进行外部评估，评估内

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SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall o.Hetherington T.w.Buggey T.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

Perturbations in the earthworm metabolite profile during a two-week exposure to metformin

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Emerging Contaminants 2024年第3期10卷 221-229页

作者： J.D.Gillis G.w.Price S.o.Prasher Department of Bioresource Engineering McGill UniversityFaculty of Agricultural and Environmental SciencesMacdonald-Stewart Building MS1-02721111 Lakeshore RoadSainte-Anne-de-BellevueQuebecH9X 3V9Canada Department of Engineering Dalhousie UniversityFaculty of Agriculture39 Cox RoadPO Box 550TruroNova ScotiaB2N 5E3Canada

Metformin is among the most prescribed pharmaceuticals in many countries,and as a result has shown up in biosolids derived from municipal wastewater treatment that are destined for land *** humans taking metformin,the effects include reduced glucose uptake in the intestine,a reduction in gluconeogenesis,increased oxidation of fatty acids,and reduced fatty acid *** effects of metformin on soil-dwelling organisms are not well *** study tested the effects of metformin exposure(0,10,40,160,640μg g^(-1))on the earthworm(***)at four time points(6 h,2 d,7 d,and 14 d)using GC-MS to reveal sub-lethal effects and elucidate potential modes of action for *** were no mortalities observed,and earthworms exposed to the highest concentrations(160 and 640μg g^(-1))gained weight relative to the control on days 7 and *** reductions on day 7 were observed for glucose and malic acid(consistent with a reduction in gluconeogenesis),and for palmitic and margaric acid(consistent with increased oxidation and reduced synthesis of fatty acids).Lactic acid ranked first and second among canonicals 1 and 2 respectively and led to significant differences in discriminant scores across concentration and *** levels increased to equal or greater than the control on day 14,likely caused by reduced exposure as metformin is reported to be readily transformed by microorganisms under aerobic *** observations were consistent with the known effects of metformin in humans,and suggests that a similar mode of action exists in earthworms.

关键词： Metabolites Toxicity Earthworms Metformin GC-MS

The CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.w.J.Hubbard o.Hetherington D.J.Hall T.w.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

Sensing nanoscale electromagnetic forces when the heat is on

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National Science Review 2024年第7期11卷 64-65页

作者： Eric o.Potma Department of Chemistry University of California

In scanning probe microscopy(SPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. SPM contrast is derived from the physical interplay between the tip and the sample. A special class of SPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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Electrogenic sulfur oxidation mediated by cable bacteria and its ecological effects

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Environmental Science and Ecotechnology 2024年第4期20卷 34-41页

作者： Zhenyu wang Leonid Digel Yongqiang Yuan Hui Lu Yonggang Yang Carsten Vogt Hans-Hermann Richnow Lars Peter nielsen Department of Isotope Biogeochemistry Helmholtz Centre for Environmental Research e UFZPermoserstraße 1504318LeipzigGermany Center for Electromicrobiology Department of BiologyAarhus UniversityDK-8000AarhusDenmark Key Laboratory of Karst Georesources and Environment Ministry of EducationCollege of Resources and Environmental EngineeringGuizhou UniversityGuiyang550025China School of Environmental Science and Engineering Sun Yat-Sen UniversityGuangzhou510006China School of Life Science and Engineering Foshan UniversityFoshan528225China State Key Laboratory of Applied Microbiology Southern China Institute of MicrobiologyGuangdong Academy of SciencesGuangzhou510007China

At the sediment-water interfaces,filamentous cable bacteria transport electrons from sulfide oxidation along their filaments towards oxygen or nitrate as electron *** multicellular bacteria belonging to the family Desulfobulbaceae thus form a biogeobattery that mediates redox processes between multiple *** bacteria were first reported in *** the past years,cable bacteria have been found to be widely distributed across the *** potential in shaping the surface water environments has been extensively studied but is not fully *** this review,the biogeochemical characteristics,conduction mechanisms,and geographical distribution of cable bacteria,as well as their ecological effects,are systematically reviewed and *** insights for understanding and applying the role of cable bacteria in aquatic ecology are summarized.

关键词： Cable bacteria Electrogenic sulfur oxidation Long-distance electron transfer Aquatic ecology