The impact of model grid zooming on tracer transport in the 1999/2000 Arctic polar vortex

International audienceWe have used a 3D chemistry transport model to evaluate the transport of HF and CH4 in the stratosphere during the Arctic winter of 1999/2000. Several model experiments were carried out with the use of a zoom algorithm to investigate the effect of different horizontal resolutions. Balloon-borne and satellite-borne observations of HF and CH4 were used to test the model. In addition, air mass descent rates within the polar vortex were calculated and compared to observations. Outside the vortex the model results agree well with the observations, but inside the vortex the model underestimates the observed vertical gradient in HF and CH4, even when the highest available resolution (1°×1°) is applied. The calculated diabatic descent rates agree with observations above potential temperature levels of 450 K. These model results suggest that too strong mixing through the vortex edge could be a plausible cause for the model discrepancies, associated with the calculated mass fluxes, although other reasons are also discussed. Based on our model experiments we conclude that a global 6°×9° resolution is too coarse to represent the polar vortex, whereas the higher resolutions, 3°×2° and 1°×1°, yield similar results, even with a 6°×9° resolution in the tropical region

The ecology of human-caused mortality for a protected large carnivore

Mitigating human-caused mortality for large carnivores is a pressing global challenge for wildlife conservation. However, mortality is almost exclusively studied at local (within-population) scales creating a mismatch between our understanding of risk and the spatial extent most relevant to conservation and management of wide-ranging species. Here, we quantified mortality for 590 radio-collared mountain lions statewide across their distribution in California to identify drivers of human-caused mortality and investigate whether human-caused mortality is additive or compensatory. Human-caused mortality, primarily from conflict management and vehicles, exceeded natural mortality despite mountain lions being protected from hunting. Our data indicate that human-caused mortality is additive to natural mortality as population-level survival decreased as a function of increasing human-caused mortality and natural mortality did not decrease with increased human-caused mortality. Mortality risk increased for mountain lions closer to rural development and decreased in areas with higher proportions of citizens voting to support environmental initiatives. Thus, the presence of human infrastructure and variation in the mindset of humans sharing landscapes with mountain lions appear to be primary drivers of risk. We show that human-caused mortality can reduce population-level survival of large carnivores across large spatial scales, even when they are protected from hunting

Information retrieval and text mining technologies for chemistry

Efficient access to chemical information contained in scientific literature, patents, technical reports, or the web is a pressing need shared by researchers and patent attorneys from different chemical disciplines. Retrieval of important chemical information in most cases starts with finding relevant documents for a particular chemical compound or family. Targeted retrieval of chemical documents is closely connected to the automatic recognition of chemical entities in the text, which commonly involves the extraction of the entire list of chemicals mentioned in a document, including any associated information. In this Review, we provide a comprehensive and in-depth description of fundamental concepts, technical implementations, and current technologies for meeting these information demands. A strong focus is placed on community challenges addressing systems performance, more particularly CHEMDNER and CHEMDNER patents tasks of BioCreative IV and V, respectively. Considering the growing interest in the construction of automatically annotated chemical knowledge bases that integrate chemical information and biological data, cheminformatics approaches for mapping the extracted chemical names into chemical structures and their subsequent annotation together with text mining applications for linking chemistry with biological information are also presented. Finally, future trends and current challenges are highlighted as a roadmap proposal for research in this emerging field.A.V. and M.K. acknowledge funding from the European Community’s Horizon 2020 Program (project reference: 654021 - OpenMinted). M.K. additionally acknowledges the Encomienda MINETAD-CNIO as part of the Plan for the Advancement of Language Technology. O.R. and J.O. thank the Foundation for Applied Medical Research (FIMA), University of Navarra (Pamplona, Spain). This work was partially funded by Consellería de Cultura, Educación e Ordenación Universitaria (Xunta de Galicia), and FEDER (European Union), and the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684). We thank Iñigo Garciá -Yoldi for useful feedback and discussions during the preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Modelling the impact of toxic and disturbance stress on white-tailed eagle (Haliaeetus albicilla) populations

Several studies have related breeding success and survival of sea eagles to toxic or non-toxic stress separately. In the present investigation, we analysed single and combined impacts of both toxic and disturbance stress on populations of white-tailed eagle (Haliaeetus albicilla), using an analytical single-species model. Chemical and eco(toxico)logical data reported from laboratory and field studies were used to parameterise and validate the model. The model was applied to assess the impact of ∑PCB, DDE and disturbance stress on the white-tailed eagle population in The Netherlands. Disturbance stress was incorporated through a 1.6% reduction in survival and a 10–50% reduction in reproduction. ∑PCB contamination from 1950 up to 1987 was found to be too high to allow the return of white-tailed eagle as a breeding species in that period. ∑PCB and population trends simulated for 2006–2050 suggest that future population growth is still reduced. Disturbance stress resulted in a reduced population development. The combination of both toxic and disturbance stress varied from a slower population development to a catastrophical reduction in population size, where the main cause was attributed to the reduction in reproduction of 50%. Application of the model was restricted by the current lack of quantitative dose–response relationships between non-toxic stress and survival and reproduction. Nevertheless, the model provides a first step towards integrating and quantifying the impacts of multiple stressors on white-tailed eagle populations

CARTILAGE THICKNESS MEASUREMENTS FROM PHOTO-COUNTING SPECTRAL COMPUTED TOMOGRAPHY IMAGES COMPARED WITH SYNCHROTRON RADIATION COMPUTED TOMOGRAPHY

International audienceImaging modalities which contribute to diagnosis, follow up and a better understanding of osteoarthritis are radiography, Magnetic Resonance Imaging (MRI), X-ray Computed tomography (CT), ultrasound, dual energy absorptiometry and positron emission tomography. Among these modalities, radiography is still the reference method to follow the cartilage impairment in osteoarthritis but only MRI and CT can provide three-dimensional images, MRI being more classically used in both clinical surveys and routine to visualize cartilage due to high contrast. Based on 3D MRI sequences, it is possible to perform 3D morphological maps for quantitative cartilage volume and thickness measurements. The best isotropic images that can be achieved with a 3T MR scanner is 0.63x0.63x0.68mm3 [1] and 0.3x0.3x0.3mm3 with a 7T MR scanner [2]. A new modality called Photo-Counting Spectral Computed Tomography (PCSCT) emerged recently with as main advantages to increase the resolution, the signal to noise ratio and the contrast in soft tissue compare to energy-integrating detectors that are classically used in routine CT device. From this new approach, we have shown in a previous study the interest of PCSCT virtual monoenergetic images at 60 keV for cartilage imaging [3].Zhang P et al. Clinical validation of the use of prototype software for automatic cartilage segmetation to qiantify knee cartilage in volunteers. BMC Musculoskeletal Disord. 23:19, 2022Bangarter N et al. Quantitative techniques for musculoskeletal MRI at 7 T. Quant Imaging med Surg 6:715,2016Chappard C et al. Virtual monoenergetic images from photon-counting spectral computed tomography to assess knee osteoarthritis. Eur Radio Exp, 22,6 202

CARTILAGE THICKNESS MEASUREMENTS FROM PHOTO-COUNTING SPECTRAL COMPUTED TOMOGRAPHY IMAGES COMPARED WITH SYNCHROTRON RADIATION COMPUTED TOMOGRAPHY

International audienceImaging modalities which contribute to diagnosis, follow up and a better understanding of osteoarthritis are radiography, Magnetic Resonance Imaging (MRI), X-ray Computed tomography (CT), ultrasound, dual energy absorptiometry and positron emission tomography. Among these modalities, radiography is still the reference method to follow the cartilage impairment in osteoarthritis but only MRI and CT can provide three-dimensional images, MRI being more classically used in both clinical surveys and routine to visualize cartilage due to high contrast. Based on 3D MRI sequences, it is possible to perform 3D morphological maps for quantitative cartilage volume and thickness measurements. The best isotropic images that can be achieved with a 3T MR scanner is 0.63x0.63x0.68mm3 [1] and 0.3x0.3x0.3mm3 with a 7T MR scanner [2]. A new modality called Photo-Counting Spectral Computed Tomography (PCSCT) emerged recently with as main advantages to increase the resolution, the signal to noise ratio and the contrast in soft tissue compare to energy-integrating detectors that are classically used in routine CT device. From this new approach, we have shown in a previous study the interest of PCSCT virtual monoenergetic images at 60 keV for cartilage imaging [3].Zhang P et al. Clinical validation of the use of prototype software for automatic cartilage segmetation to qiantify knee cartilage in volunteers. BMC Musculoskeletal Disord. 23:19, 2022Bangarter N et al. Quantitative techniques for musculoskeletal MRI at 7 T. Quant Imaging med Surg 6:715,2016Chappard C et al. Virtual monoenergetic images from photon-counting spectral computed tomography to assess knee osteoarthritis. Eur Radio Exp, 22,6 202

Analyse quantitative morphologique du cartilage à partir du scanner spectral à comptage de photons

International audienc