1,265 research outputs found

    Church forests and traditional wetlands: supporting rural well-being in Lake Tana Basin, Ethiopia

    Get PDF
    The Lake Tana Basin (15,114 km2) is the most economically, historically and environmentally important headwater catchment of the Upper Blue Nile River System. It is also provide benefits for downstream eastern Nile countries. This ecologically important landscape comprises of isolated patches of scattered natural forest sites, wetlands, communal grasslands and agricultural lands. The remaining patches of forests are found in the area surrounding the 3,500 orthodox churches and monasteries. These sacred natural sites are rich in biodiversity provides multiple ecosystem services such as carbon sequestration, source of drinking and holy water, soil erosion control, harbor pollinator species, sources of seed, fuelwood, research and educational site, spiritual purpose, tourism and provide shade and local healing medicines. Some of which are also provided by the wetlands and grasslands.Rapidly growing population, environmental and social changes in the basin adversely affect the characteristics of local ecosystems. Consequently, the widespread alteration and fragmentation of the native land cover became the greatest threat to the ecosystem. Threats to the isolated fragmented church forests, wetlands and grasslands are many. Over-harvesting of wood products, overgrazing, and transformation to an area of cultivated lands and eucalyptus plantation leads to significant reduction and loss of ecosystem functions and services and affect rural human well-being. Remote sensing based detailed information on the wide range of ecosystem service changes and their economic values and livelihood impacts for different groups at local scale are largely absent in Lake Tana basin. This study will estimate the status, trend, extent, and impact of natural ecosystems transformation incorporating stakeholder perceptions and values across the study area. Spatial assessments of ecosystem services are valuable for policy and decision-making processes and provides a stimulus to conserve the ecosystems that offer the most valuable resources.<br/

    Detecting respiratory bacterial communities of wild dolphins: Implications for animal health

    Get PDF
    Infectious diseases contribute to the vulnerable status of marine mammals, including respiratory illnesses. This study aimed to capture exhaled breath condensate (blow) for microbial identification from wild Indo-Pacific bottlenose dolphins Tursiops aduncus. Individual dolphins were sampled by holding a funnel connected to a 50 ml centrifuge tube over the blowhole of the animal near shore in Shark Bay (SB), Western Australia. Four individuals were sampled on 2 occasions along with seawater samples. Comparative blow and pool water samples were collected from 4 individual common bottlenose dolphins Tursiops truncatus housed in the National Aquarium (NA), Baltimore, Maryland, USA. Bacteria were identified using the V4 region of the 16S rRNA gene from extracted DNA. We identified bacteria independent of seawater in SB dolphins, which included the classes Alphaproteobacteria (26.1%) and Gammaproteobacteria (25.8%); the phyla Bacteroidetes (15.6%) and Fusobacteria (7.2%); and the genera Pseudomonas (11.5%), Pedomicrobium (4.5%), Streptobacillus (3.7%), Phenylobacterium (2.2%) and Sphingomonas (2.1%). There were broad similarities in phyla between SB and NA dolphins yet there were differences between lower taxonomic groups. A number of operational taxonomic units (OTUs) were shared between dolphin individuals, which may be a result of their genetic lineage (siblings or parentage), shared living and social interactions. A number of genera were observed in SB dolphins which have species known to be infectious in marine mammals such as Pseudomonas, Mycoplasma and Streptococcus. This study successfully characterised bacteria from DNA captured in blow from wild dolphins. The ability to capture these communities from individuals in the wild provides a novel health indicator

    Anisotropy of the Mobility of Pentacene from Frustration

    Get PDF
    The bandstructure of pentacene is calculated using first-principles density functional theory. A large anisotropy of the hole and electron effective masses within the molecular planes is found. The band dispersion of the HOMO and the LUMO is analyzed with the help of a tight-binding fit. The anisotropy is shown to be intimately related to the herringbone structure.Comment: Accepted for publication in Synthetic Metal

    BRAIN Α-TOCOPHEROL CONCENTRATION IS INVERSELY ASSOCIATED WITH NEUROFIBRILLARY TANGLE COUNTS IN BRAIN REGIONS AFFECTED IN EARLIER BRAAK STAGES: A CROSS-SECTIONAL FINDING IN THE OLDEST OLD

    Get PDF
    Objectives: Higher vitamin E status has been associated with lower risk of Alzheimer’s disease (AD). However, evidence of the association of vitamin E concentration in neural tissue with AD pathologies is limited. Design: The cross-sectional relationship between the human brain concentrations of α- and γ-tocopherol and the severity of AD pathologies – neurofibrillary tangle (NFT) and neuritic plaque (NP) – was investigated. Setting & Participants: Brains from 43 centenarians (≥ 98 years at death) enrolled in the Phase III of the Georgia Centenarian Study were collected at autopsy. Measurements: Brain α- and γ-tocopherol concentrations (previously reported) were averaged from frontal, temporal, and occipital cortices. NP and NFT counts (previously reported) were assessed in frontal, temporal, parietal, entorhinal cortices, amygdala, hippocampus, and subiculum. NFT topological progression was assessed using Braak staging. Multiple linear regression was performed to assess the relationship between tocopherol concentrations and NP or NFT counts, with and without adjustment for covariates. Results: Brain α-tocopherol concentrations were inversely associated with NFT but not NP counts in amygdala (β = -2.67, 95% CI [-4.57, -0.79]), entorhinal cortex (β = -2.01, 95% CI [-3.72, -0.30]), hippocampus (β = -2.23, 95% CI [-3.82, -0.64]), and subiculum (β = -2.52, 95% CI [-4.42, -0.62]) where NFT present earlier in its topological progression, but not in neocortices. Subjects with Braak III-IV had lower α-tocopherol (median = 69,622 pmol/g, IQR = 54,389-72,155 pmol/g) than those with Braak I-II (median = 72,108 pmol/g, IQR = 64,056-82,430 pmol/g), but the difference was of borderline significance (p = 0.063). γ-Tocopherol concentrations were not associated with either NFT or NP counts in any brain regions assessed. Conclusions: Higher brain α-tocopherol level is specifically associated with lower NFT counts in brain structures affected in earlier Braak stages. Our findings emphasize the possible importance of α-tocopherol intervention timing in tauopathy progression and warrant future clinical trials

    Critical Dynamics of Magnets

    Get PDF
    We review our current understanding of the critical dynamics of magnets above and below the transition temperature with focus on the effects due to the dipole--dipole interaction present in all real magnets. Significant progress in our understanding of real ferromagnets in the vicinity of the critical point has been made in the last decade through improved experimental techniques and theoretical advances in taking into account realistic spin-spin interactions. We start our review with a discussion of the theoretical results for the critical dynamics based on recent renormalization group, mode coupling and spin wave theories. A detailed comparison is made of the theory with experimental results obtained by different measuring techniques, such as neutron scattering, hyperfine interaction, muon--spin--resonance, electron--spin--resonance, and magnetic relaxation, in various materials. Furthermore we discuss the effects of dipolar interaction on the critical dynamics of three--dimensional isotropic antiferromagnets and uniaxial ferromagnets. Special attention is also paid to a discussion of the consequences of dipolar anisotropies on the existence of magnetic order and the spin--wave spectrum in two--dimensional ferromagnets and antiferromagnets. We close our review with a formulation of critical dynamics in terms of nonlinear Langevin equations.Comment: Review article (154 pages, figures included

    The Muonium Atom as a Probe of Physics beyond the Standard Model

    Get PDF
    The observed interactions between particles are not fully explained in the successful theoretical description of the standard model to date. Due to the close confinement of the bound state muonium (M=μ+e−M = \mu^+ e^-) can be used as an ideal probe of quantum electrodynamics and weak interaction and also for a search for additional interactions between leptons. Of special interest is the lepton number violating process of sponteanous conversion of muonium to antimuonium.Comment: 15 pages,6 figure
    • …
    corecore