331 research outputs found

    Incorporating ecological functions in conservation decision making

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    Systematic conservation planning has become a standard approach globally, but prioritization of conservation efforts hardly considers species traits in decision making. This can be important for species persistence and thus adequacy of the conservation plan. Here, we developed and validated a novel approach of incorporating trophic information into a systematic conservation planning framework. We demonstrate the benefits of this approach using fish data from Europe's second largest river, the Danube. Our results show that adding trophic information leads to a different spatial configuration of priority areas at no additional cost. This can enhance identification of priority refugia for species in the lower position of the trophic web while simultaneously identifying areas that represent a more diverse species pool. Our methodological approach to incorporating species traits into systematic conservation planning is generally applicable, irrespective of realm, geographical area, and species composition and can potentially lead to more adequate conservation plans.SL was supported by ARC DECRA fellowship, project number DE130100565. VH was supported by a Ramon y Cajal contract (RYC‐2013‐13979) funded by the Spanish Government

    KiDS+VIKING+GAMA: Halo occupation distributions and correlations of satellite numbers with a new halo model of the galaxy-matter bispectrum for galaxy-galaxy-galaxy lensing

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    Halo models and halo occupation distributions (HODs) are important tools to model the galaxy and matter distribution. We present and assess a new method for constraining the parameters of HODs using the gravitational lensing shear around galaxy pairs, galaxy-galaxy-galaxy-lensing (G3L). In contrast to galaxy-galaxy-lensing, G3L is sensitive to correlations between the per-halo numbers of galaxies from different populations. We use G3L to probe these correlations and test the default hypothesis that they are negligible. We derive a halo model for G3L and validate it with realistic mock data from the Millennium Simulation and a semi-analytic galaxy model. Then, we analyse public data from the Kilo-Degree Survey (KiDS), the VISTA Infrared Kilo-Degree Galaxy Survey (VIKING) and data from the Galaxy And Mass Assembly Survey (GAMA) to infer the HODs of galaxies at z<0.5z<0.5 in five different stellar mass bins between 108.5h−2M⊙10^{8.5}h^{-2} M_\odot and 1011.5h−2M⊙10^{11.5}h^{-2} M_\odot and two colours (red and blue), as well as correlations between satellite numbers. The analysis recovers the true HODs in the simulated data within the 68%68\% credibility range. The inferred HODs vary significantly with colour and stellar mass. There is also strong evidence (>3σ>3\sigma) for correlations, increasing with halo mass, between the numbers of red and blue satellites and galaxies with stellar masses below $10^{10} \Msun. Possible causes of these correlations are the selection of similar galaxies in different samples, the survey flux limit, or physical mechanisms like a fixed ratio between the satellite numbers of distinct populations. The decorrelation for halos with smaller masses is probably an effect of shot noise by low-occupancy halos. The inferred HODs can be used to complement galaxy-galaxy-lensing or galaxy clustering HOD studies or as input to cosmological analyses and improved mock galaxy catalogues.Comment: 20 pages + Appendix, 14 Figures. Submitted to Astronomy & Astrophysics. Abstract is abridge

    Feasibility of the Engagerℱ aortic transcatheter valve system using a flexible over-the-wire design

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    OBJECTIVES The aim was to investigate the safety and feasibility of the redesigned Engagerℱ transcatheter aortic valve implantation (TAVI) system. METHODS Transapical aortic valve implantation with the Engagerℱ valve prosthesis was intended in 11 patients, and performed in 10. Endpoints were defined according to the valve academic research consortium recommendations for reporting outcomes of TAVI in clinical trials. RESULTS All 10 patients were implanted successfully. No devicerelated or delivery system complications like coronary obstruction or aortic dissection emerged. One patient (10%) died from non-device-related reasons at post-operative day 23 of multi-organ failure. The invasively measured peak-to-peak gradient after valve implantation was 7.1±3.5mmHg. In 90%, there was no or only trivial (≀grad I) aortic regurgitation due to paravalvular leakage. In 10% of the patients, aortic regurgitation grade I-II was observed. At 30-day follow up, the mean gradient was 15.6±4.9mmHg, and no more than a mild transvalvular and paravalvular aortic regurgitation was seen as assessed by transthoracic echocardiography. CONCLUSIONS Application of the Engagerℱ TAVI system is safe and feasible. Prosthesis deployment in an anatomically correct position was facilitated by the design of the valve prosthesis and was successful in all patients. No device or delivery-system-related complications emerged. Safety and feasibility endpoints were met. Good results concerning the aortic valve performance after implantation and at 30-day follow up were ascertained. These results encouraged the start of a European Pivotal trial including patients to dat

    Evaluating the climate impact of aviation emission scenarios towards the Paris agreement including COVID-19 effects

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    Aviation is an important contributor to the global economy, satisfying society’s mobility needs. It contributes to climate change through CO2 and non-CO2 effects, including contrail-cirrus and ozone formation. There is currently significant interest in policies, regulations and research aiming to reduce aviation’s climate impact. Here we model the effect of these measures on global warming and perform a bottom-up analysis of potential technical improvements, challenging the assumptions of the targets for the sector with a number of scenarios up to 2100. We show that although the emissions targets for aviation are in line with the overall goals of the Paris Agreement, there is a high likelihood that the climate impact of aviation will not meet these goals. Our assessment includes feasible technological advancements and the availability of sustainable aviation fuels. This conclusion is robust for several COVID-19 recovery scenarios, including changes in travel behaviour

    Yeast XRS2 and human NBN gene: Experimental evidence for homology using codon optimized cDNA

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    The genes, XRS2 in Saccharomyces cerevisiae and NBN in mammals, have little sequence identity at the amino acid level. Nevertheless, they are both found together with MRE11 and RAD50 in a highly conserved protein complex which functions in the repair of DNA double-strand breaks. Here, we have examined the evolutionary and functional relationship of these two genes by cross-complementation experiments. These experiments necessitated sequence correction for specific codon usage before they could be successfully conducted. We present evidence that despite extreme sequence divergence nibrin can, at least partially, replace Xrs2 in the cellular DNA damage response, and Xrs2 is able to promote nuclear localization of MRE11 in NBS cells. We discuss that the extreme sequence divergence reflects a unique adaptive pressure during evolution related to the specific eukaryotic role for both Xrs2 and nibrin in the subcellular localisation of the DNA repair complex. This, we suggest, is of particular relevance when cells are infected by viruses. The conflict hypothesis of co-evolution of DNA repair genes and DNA viruses may thus explain the very low sequence identity of these two homologous genes

    Freshwater ecoacoustics as a tool for continuous ecosystem monitoring

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    Copyright by the Ecological Society of AmericaPassive acoustic monitoring is gaining popularity in ecology as a practical and non-invasive approach to surveying ecosystems. This technique is increasingly being used to monitor terrestrial systems, particularly bird populations, given that it can help to track temporal dynamics of populations and ecosystem health without the need for expensive resampling. We suggest that underwater acoustic monitoring presents a viable, non-invasive, and largely unexplored approach to monitoring freshwater ecosystems, yielding information about three key ecological elements of aquatic environments – (1) fishes, (2) macroinvertebrates, and (3) physicochemical processes – as well as providing data on anthropogenic noise levels. We survey the literature on this approach, which is substantial but scattered across disciplines, and call for more cross-disciplinary work on recording and analysis techniques. We also discuss technical issues and knowledge gaps, including background noise, spatiotemporal variation, and the need for centralized reference collection repositories. These challenges need to be overcome before the full potential of passive acoustics in dynamic detection of biophysical processes can be realized and used to inform conservation practitioners and managers

    KiDS+VIKING+GAMA:Testing semi-analytic models of galaxy evolution with galaxy-galaxy-galaxy lensing

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    Several semi-analytic models (SAMs) try to explain how galaxies form, evolve and interact inside the dark matter large-scale structure. These SAMs can be tested by comparing their predictions for galaxy-galaxy-galaxy-lensing (G3L), which is weak gravitational lensing around galaxy pairs, with observations. We evaluate the SAMs by Henriques et al. (2015; H15) and by Lagos et al. (2012; L12), implemented in the Millennium Run, by comparing their predictions for G3L to observations at smaller scales than previous studies and also for pairs of lens galaxies from different populations. We compare the G3L signal predicted by the SAMs to measurements in the overlap of the Galaxy And Mass Assembly survey (GAMA), the Kilo-Degree Survey (KiDS), and the VISTA Kilo-degree Infrared Galaxy survey (VIKING), splitting lens galaxies into two colour and five stellar-mass samples. Using an improved G3L estimator, we measure the three-point correlation of the matter distribution for mixed lens pairs with galaxies from different samples, and unmixed lens pairs with galaxies from the same sample. Predictions by the H15 SAM agree with the observations for all colour-selected and all but one stellar-mass-selected sample with 95% confidence. Deviations occur for lenses with stellar masses below 9.5h−2M⊙9.5h^{-2}\mathrm{M}_\odot at scales below 0.2h−1Mpc0.2h^{-1}\mathrm{Mpc}. Predictions by the L12 SAM for stellar-mass selected samples and red galaxies are significantly higher than observed, while the predicted signal for blue galaxy pairs is too low. The L12 SAM predicts more pairs of small stellar-mass and red galaxies than the H15 SAM and the observations, as well as fewer pairs of blue galaxies. Likely explanations are different treatments of environmental effects by the SAMs and different models of the initial mass function. We conclude that G3L provides a stringent test for models of galaxy formation and evolution.Comment: 14 pages, 8 figures, replaced with version accepted to Astronomy & Astrophysics after considering referees comment

    It\u27s Time to Listen: There is Much to be Learned from the Sounds of Tropical Ecosystems

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    Knowledge that can be gained from acoustic data collection in tropical ecosystems is low‐hanging fruit. There is every reason to record and with every day, there are fewer excuses not to do it. In recent years, the cost of acoustic recorders has decreased substantially (some can be purchased for under US$50, e.g., Hill et al. 2018) and the technology needed to store and analyze acoustic data is continuously improving (e.g., Corrada Bravo et al. 2017, Xie et al. 2017). Soundscape recordings provide a permanent record of a site at a given time and contain a wealth of invaluable and irreplaceable information. Although challenges remain, failure to collect acoustic data now in tropical ecosystems would represent a failure to future generations of tropical researchers and the citizens that benefit from ecological research. In this commentary, we (1) argue for the need to increase acoustic monitoring in tropical systems; (2) describe the types of research questions and conservation issues that can be addressed with passive acoustic monitoring (PAM) using both short‐ and long‐term data in terrestrial and freshwater habitats; and (3) present an initial plan for establishing a global repository of tropical recordings

    Sounding the call for a global library of underwater biological sounds

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    © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Parsons, M., Lin, T.-H., Mooney, T., Erbe, C., Juanes, F., Lammers, M., Li, S., Linke, S., Looby, A., Nedelec, S., Van Opzeeland, I., Radford, C., Rice, A., Sayigh, L., Stanley, J., Urban, E., & Di Iorio, L. Sounding the call for a global library of underwater biological sounds. Frontiers in Ecology and Evolution, 10, (2022): 810156, https://doi.org/10.3389/fevo.2022.810156.Aquatic environments encompass the world’s most extensive habitats, rich with sounds produced by a diversity of animals. Passive acoustic monitoring (PAM) is an increasingly accessible remote sensing technology that uses hydrophones to listen to the underwater world and represents an unprecedented, non-invasive method to monitor underwater environments. This information can assist in the delineation of biologically important areas via detection of sound-producing species or characterization of ecosystem type and condition, inferred from the acoustic properties of the local soundscape. At a time when worldwide biodiversity is in significant decline and underwater soundscapes are being altered as a result of anthropogenic impacts, there is a need to document, quantify, and understand biotic sound sources–potentially before they disappear. A significant step toward these goals is the development of a web-based, open-access platform that provides: (1) a reference library of known and unknown biological sound sources (by integrating and expanding existing libraries around the world); (2) a data repository portal for annotated and unannotated audio recordings of single sources and of soundscapes; (3) a training platform for artificial intelligence algorithms for signal detection and classification; and (4) a citizen science-based application for public users. Although individually, these resources are often met on regional and taxa-specific scales, many are not sustained and, collectively, an enduring global database with an integrated platform has not been realized. We discuss the benefits such a program can provide, previous calls for global data-sharing and reference libraries, and the challenges that need to be overcome to bring together bio- and ecoacousticians, bioinformaticians, propagation experts, web engineers, and signal processing specialists (e.g., artificial intelligence) with the necessary support and funding to build a sustainable and scalable platform that could address the needs of all contributors and stakeholders into the future.Support for the initial author group to meet, discuss, and build consensus on the issues within this manuscript was provided by the Scientific Committee on Oceanic Research, Monmouth University Urban Coast Institute, and Rockefeller Program for the Human Environment. The U.S. National Science Foundation supported the publication of this article through Grant OCE-1840868 to the Scientific Committee on Oceanic Research
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