656 research outputs found

    Inducing Private Wildfire Risk Mitigation: Experimental Investigation of Measures on Adjacent Public Lands

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    Increasing private wildfire risk mitigation is an important part of the larger forest restoration policy challenge. Data from an economic experiment are used to evaluate the effectiveness of providing fuel treatments on public land adjacent to private land to induce private wildfire risk mitigation. Results show evidence of “crowding out” where public spending can decrease the level of private risk mitigation. However, a policy prescription that ameliorates this crowding out is identified. Participants undertake more mitigation when fuel treatments on publicly owned lands are conditional on a threshold level of private mitigation effort and information describing each participant’s spending is provided. Key Words:

    Aquatic Invasive Species Change Ecosystem Services from the World\u27s Largest Wild Sockeye Salmon Fisheries in Alaska

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    This study combines a multi-method approach to structured expert judgment with market valuation to forecast fisheries damages from introduced invasive species. The method is applied to a case study of Alaska’s first submersed aquatic invasive plant, Elodea spp., threatening Alaska’s salmon fisheries. Assuming that Elodea spp. remains unmanaged, estimated mean damages to commercial sockeye fisheries aggregated across Alaska amount to a potential 159millionannuallywitha5159 million annually with a 5% chance of exceeding 577 million annually (2015USD).Theassociatedmeanlossofnaturalcapitalamountsto2015 USD). The associated mean loss of natural capital amounts to 5.1 billion cumulatively over the next 100 years reaching $400 million after 10 years. Results from the expert elicitation indicate that there is a 35% chance of positive net benefits associated with the believed positive effects of Elodea spp. on sockeye salmon (Oncorhynchus nerka). Despite the potential for positive net gains, the magnitude of the most probable damage estimate may justify substantial investment in keeping productive freshwater systems free of aquatic invasive species. The damage estimate for Alaska is significantly larger than similar estimates in the Great Lakes where ecosystems are already impaired by multiple aquatic invasive species, underscoring the value of keeping functioning ecosystems with global market value productive. This study is the first to estimate ecosystem service loss associated with introduction of an aquatic invasive species to freshwater habitat that supports the world’s most valuable wild sockeye salmon fisheries. Important policy implications related to natural resource management and efficient allocation of scarce resources are discusse

    Imaging anomalous nematic order and strain in optimally doped BaFe2_2(As,P)2_2

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    We present the strain and temperature dependence of an anomalous nematic phase in optimally doped BaFe2_2(As,P)2_2. Polarized ultrafast optical measurements reveal broken 4-fold rotational symmetry in a temperature range above TcT_c in which bulk probes do not detect a phase transition. Using ultrafast microscopy, we find that the magnitude and sign of this nematicity vary on a 50−100 Ό{50{-}100}~\mum length scale, and the temperature at which it onsets ranges from 40 K near a domain boundary to 60 K deep within a domain. Scanning Laue microdiffraction maps of local strain at room temperature indicate that the nematic order appears most strongly in regions of weak, isotropic strain. These results indicate that nematic order arises in a genuine phase transition rather than by enhancement of local anisotropy by a strong nematic susceptibility. We interpret our results in the context of a proposed surface nematic phase

    Imaging anomalous nematic order and strain in optimally doped BaFe2_2(As,P)2_2

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    We present the strain and temperature dependence of an anomalous nematic phase in optimally doped BaFe2_2(As,P)2_2. Polarized ultrafast optical measurements reveal broken 4-fold rotational symmetry in a temperature range above TcT_c in which bulk probes do not detect a phase transition. Using ultrafast microscopy, we find that the magnitude and sign of this nematicity vary on a 50−100 Ό{50{-}100}~\mum length scale, and the temperature at which it onsets ranges from 40 K near a domain boundary to 60 K deep within a domain. Scanning Laue microdiffraction maps of local strain at room temperature indicate that the nematic order appears most strongly in regions of weak, isotropic strain. These results indicate that nematic order arises in a genuine phase transition rather than by enhancement of local anisotropy by a strong nematic susceptibility. We interpret our results in the context of a proposed surface nematic phase

    Inducing private wildfire risk mitigation: Experimental investigation of measures on adjacent public lands

    Get PDF
    Increasing private wildfire risk mitigation is an important part of the larger forest restoration policy challenge. Data from an economic experiment are used to evaluate the effectiveness of providing fuel treatments on public land adjacent to private land to induce private wildfire risk mitigation. Results show evidence of “crowding out” where public spending can decrease the level of private risk mitigation. However, a policy prescription that ameliorates this crowding out is identified. Participants undertake more mitigation when fuel treatments on publicly owned lands are conditional on a threshold level of private mitigation effort and information describing each participant’s spending is provided

    Pericellular colocalisation and interactive properties of type VI collagen and perlecan in the intervertebral disc

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    The aim of this study was to immunolocalise type VI collagen and perlecan and determine their interactive properties in the intervertebral disc (IVD). Confocal laser scanning microscopy co-localised perlecan with type VI collagen as pericellular components of IVD cells and translamellar cross-bridges in ovine and murine IVDs. These cross-bridges were significantly less abundant in the heparin sulphate deficient Hspg2 exon 3 null mouse IVD than in wild type. This association of type VI collagen with elastic components provides clues as to its roles in conveying elastic recoil properties to annular tissues. Perlecan and type VI collagen were highly interactive in plasmon resonance studies. Pericellular colocalisation of perlecan and type VI collagen provides matrix stabilisation and cell-matrix communication which allows IVD cells to perceive and respond to perturbations in their biomechanical microenvironment. Perlecan, at the cell surface, provides an adhesive interface between the cell and its surrounding extracellular matrix. Elastic microfibrillar structures regulate tensional connective tissue development and function. The 2010 Global Burden of Disease study examined 291 disorders and identified disc degeneration and associated low back pain as the leading global musculoskeletal disorder emphasising its massive socioeconomic impact and the need for more effective treatment strategies. A greater understanding of how the IVD achieves its unique biomechanical functional properties is of great importance in the development of such therapeutic measures

    The CS sulphation motifs 4C3, 7D4, 3B3[-]; and perlecan identify stem cell populations and niches, activated progenitor cells and transitional tissue development in the fetal human elbow

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    We compared the immunohistochemical distribution of (i) the novel chondroitin sulphate (CS) sulphation motifs 7D4, 4C3 and 3B3[-], (ii) native heparan sulphate (HS) and Δ-HS ‘stubs’ generated by heparitinase III digestion and (iii) the HS-proteoglycan, perlecan, in the foetal human elbow joint. Putative stem cell populations associated with hair bulbs, humeral perichondrium, humeral and ulnar rudiment stromal/perivascular tissues expressed the CS motifs 4C3, 7D4 and 3B3[-] as well as perlecan in close association but not co-localised. Chondrocytes in the presumptive articular cartilage of the foetal elbow expressed the 4C3 and 7D4 CS sulphation motifs consistent with earlier studies on the expression of these motifs in knee cartilage following joint cavitation. The present study also indicated that hair bulbs, skin, perichondrium and rudiment stroma were all perlecan rich progenitor cell niches that contributed to the organisation and development of the human foetal elbow joint and associated connective tissues. One of the difficulties in determining the precise role of stem cells in tissue development and repair processes is their short engraftment period and the lack of specific markers which differentiate the activated stem cell lineages from the resident cells. The CS sulphation motifs 7D4, 4C3 and 3B3[-] decorate cell surface proteoglycans on activated stem/progenitor cells and thus can be used to identify these cells in transitional areas of tissue development and in repair tissues and may be applicable to determining a more precise mode of action of stem cells in these processes. Isolation of perlecan from 12-14 week gestational age foetal knee rudiments demonstrated that perlecan in these foetal tissues was a HS-CS hybrid proteoglyca

    Nonlinear Mixed-Effect Pharmacokinetic Modeling and Distribution of Doxycycline in Healthy Female Donkeys after Multiple Intragastric Dosing–Preliminary Investigation

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    Doxycycline (DXC) is a broad-spectrum antibacterial antimicrobial administered to horses for the treatment of bacterial infections which may also affect donkeys. Donkeys have a different metabolism than horses, leading to differences in the pharmacokinetics of drugs compared to horses. This study aimed to describe the population pharmacokinetics of DXC in donkeys. Five doses of DXC hyclate (10 mg/kg) were administered via a nasogastric tube, q12 h, to eight non-fasted, healthy, adult jennies. Serum, urine, synovial fluid and endometrium were collected for 72 h following the first administration. Doxycycline concentration was measured by competitive enzyme immunoassay. Serum concentrations versus time data were fitted simultaneously using the stochastic approximation expectation-maximization algorithm for nonlinear mixed effects. A one-compartment model with linear elimination and first-order absorption after intragastric administration, best described the available pharmacokinetic data. Final parameter estimates indicate that DXC has a high volume of distribution (108 L/kg) as well as high absorption (10.3 h-1) in donkeys. However, results suggest that oral DXC at 10 mg/kg q12 h in donkeys would not result in a therapeutic concentration in serum, urine, synovial fluid or endometrium by comparison to the minimum inhibitory concentration of common equine pathogens. Further studies are recommended to identify appropriate dosage and dosing intervals of oral DXC in donkeys

    Double Lorentzian Atomic Prism

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    We present an atomic prism spectrometer that utilizes the steep linear dispersion between two strongly absorbing hyperfine resonances of rubidium. We resolve spectral lines 50 MHz apart and, utilizing a larger part of the available spectrum than only between the two resonances, we spatially separate collinear pump, signal, and idler beams resulting from a four-wave mixing process. Due to the high transparency possible between the resonances, these results have applications in the filtering of narrow-band entangled photons and interaction-free measurements
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