10 research outputs found

    Bat Ensembles Differ in Response to Use Zones in a Tropical Biosphere Reserve

    Get PDF
    Biosphere reserves, designated under The United Nations Education, Scientific and Cultural Organization's (UNESCO) Man and Biosphere Programme, aim to sustainably integrate protected areas into the biological and economic landscape around them by buffering strictly protected habitats with zones of limited use. However, the effectiveness of biosphere reserves and the contribution of the different zones of use to protection is poorly known. We assessed the diversity and activity of bats in the Crocker Range Biosphere Reserve (CRBR) in Sabah, Malaysia, using harp traps, mist nets and acoustic surveys in each zone-core, buffer, transition and in agricultural plots outside of the reserve. We captured 30 species, bringing the known bat fauna of CRBR to 50 species, half of Borneo's bat species. Species composition and acoustic activity varied among zones and by foraging ensemble, with the core and buffer showing particular importance for conserving forest-dependent insectivorous bats. Frugivorous bats were found in all zones but were the most abundant and most species-rich ensemble within agricultural sites. Although sampling was limited, bat diversity and activity was low in the transition zone compared to other zones, indicating potential for management practices that increase food availability and enhance biodiversity value. We conclude that, collectively, the zones of the CRBR effectively protect diversity, but the value of the transition zone can be improved

    Conflicting Confinement Effects on the <i>T</i><sub>g</sub>, Diffusivity, and Effective Viscosity of Polymer Films: A Case Study with Poly(isobutyl methacrylate) on Silica and Possible Resolution

    No full text
    The glass transition temperature (<i>T</i><sub>g</sub>), in-plane diffusivity (<i>D</i>), and effective viscosity (η<sub>eff</sub>) were measured for the same thin film system of poly­(isobutyl methacrylate) supported by silica (PiBMA/SiOx). We found that both the <i>T</i><sub>g</sub> and <i>D</i> were independent of the film thickness (<i>h</i><sub>0</sub>), but η<sub>eff</sub> decreased with decreasing <i>h</i><sub>0</sub>. We envisage the different <i>h</i><sub>0</sub> dependencies to be caused by <i>T</i><sub>g</sub>, <i>D</i>, and η<sub>eff</sub> being different functions of the local <i>T</i><sub>g</sub>’s (<i>T</i><sub>g,<i>i</i></sub>) or viscosities (η<sub><i>i</i></sub>), which vary with the film depth. By assuming a three-layer model and that <i>T</i><sub>g</sub>(<i>h</i><sub>0</sub>) = ⟨<i>T</i><sub>g,<i>i</i></sub>⟩, <i>D</i>(<i>h</i><sub>0</sub>) ∼ <i>k</i><sub>B</sub><i>T</i>/⟨η<sub><i>i</i></sub>⟩, and η<sub>eff</sub>(<i>h</i><sub>0</sub>) = <i>h</i><sub>0</sub><sup>3</sup>/3<i>M</i><sub>tot</sub>(η<sub><i>i</i></sub>), where ⟨...⟩ denotes spatial averaging and <i>M</i><sub>tot</sub> is the mobility of the films, we were able to account for the experimental data. By extending these ideas to the analogous data of polystyrene supported by silica (PS/SiOx), a resolution was found for the long-standing inconsistency regarding the effects of confinement on the dynamics of polymer films

    First asteroid gas sample delivered by the Hayabusa2 mission:A treasure box from Ryugu

    Get PDF
    「はやぶさ2」ミッションによる世界初の小惑星からのガスサンプル:リュウグウからのたまて箱. 京都大学プレスリリース. 2022-10-21.The Hayabusa2 spacecraft returned to Earth from the asteroid 162173 Ryugu on 6 December 2020. One day after the recovery, the gas species retained in the sample container were extracted and measured on-site and stored in gas collection bottles. The container gas consists of helium and neon with an extraterrestrial ³He/⁴He and ²⁰Ne/²²Ne ratios, along with some contaminant terrestrial atmospheric gases. A mixture of solar and Earth’s atmospheric gas is the best explanation for the container gas composition. Fragmentation of Ryugu grains within the sample container is discussed on the basis of the estimated amount of indigenous He and the size distribution of the recovered Ryugu grains. This is the first successful return of gas species from a near-Earth asteroid

    Noble gases and nitrogen in samples of asteroid Ryugu record its volatile sources and recent surface evolution

    No full text
    International audienceThe near-Earth carbonaceous asteroid (162173) Ryugu is expected to contain volatile chemical species that could provide information on the origin of Earth’s volatiles. Samples of Ryugu were retrieved by the Hayabusa2 spacecraft. We measure noble gas and nitrogen isotopes in Ryugu samples, finding they are dominated by pre-solar and primordial components, incorporated during Solar System formation. Noble gas concentrations are higher than those in Ivuna-type carbonaceous (CI) chondrite meteorites. Several host phases of isotopically distinct nitrogen have heterogeneous abundances between the samples. Our measurements support a close relationship between Ryugu and CI chondrites. Noble gases produced by galactic cosmic rays, indicating ~5 Myr exposure, and from implanted solar wind, record the recent irradiation history of Ryugu after it migrated to its current orbit

    First asteroid gas sample delivered by the Hayabusa2 mission: A treasure box from Ryugu

    No full text
    corecore