155 research outputs found

    Land-use controls for outdoor recreation areas

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    Land-use planning and control is fast becoming a major issue in the United States. Dwindling natural resources, a growing population, a recognized need for a quality environment, and several incidents of controversial resource management have brought land-use problems to the public eye. State land-use legislation, numerous court cases, and extensive debate have resulted. Central to the general debate is concern over the role of government in this area, formerly considered to be the realm of the individual and private firm. This paper is designed to help clarify the role of government in land-use planning and control by analyzing the powers available to government entities in providing opportunities for outdoor recreation.https://lib.dr.iastate.edu/specialreports/1074/thumbnail.jp

    Notes on Eastern North American Butterflies

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    Editor’s Note (Harry Pavulaan). New natural history elements and distribution records of several eastern North American butterflies are reported. While diversity and distribution of butterflies in the eastern United States are commonly believed to be fully known, the findings presented here show that much is yet to be learned of our butterfly fauna. Includes: 1. Pages 1-3 Lethe eurydice and L. appalachia Larvae (Nymphalidae: Satyrinae) Eat Their Shed Cuticle (Exuvia) Soon after Molting in Vermont, USA by David J. Hoag Abstract Larvae of Lethe eurydice and L. appalachia were observed eating their newly shed cuticle (exuvia). Further studies are needed to examine the extent of this unique dietary habit within the Satyrinae. 2. Page 4 Virginia state record of Phyciodes phaon (W. H. Edwards, 1864) (Nymphalidae: Limenitidinae) by Harry Pavulaan Abstract A state record specimen of Phyciodes phaon, originally reported by the author in the Virginia Butterfly Bulletin (Pavulaan, 2000), is illustrated for the first time with a view of location collected. 3. Pages 5-13 Butterflies of the Potomac River Woodlands in Leesburg, Loudoun Co., Virginia: A Depauperate Fauna? by Harry Pavulaan Abstract Butterfly observations made over a 16-year period (2005-2020) in the deciduous woodland habitat along the Potomac River in Leesburg, Virginia reveal a depauperate butterfly fauna in a region otherwise known for its rich butterfly diversity. While the forest canopy contains a high diversity of deciduous tree species, and patches of understory shrubs show limited variety, the herb flora of the forest floor is severely lacking due to uncontrolled deer browsing, poor soil conditions and prolonged annual summer droughts. The butterfly fauna is summarized here. 4. Page 14 Limenitis a. arthemis (White Admiral) in Coastal Southeastern Virginia by Brian Taber Abstract Limenitis a. arthemis is reported from coastal southeastern Virginia for the first time. 5. Pages 15-16 Three Species of the Pearly-Eye Genus Enodia (Hübner, 1819) Observed Together in Colonial National Historical Park, Virginia by Kenneth Lorenzen Abstract Butterflies of the Pearly-eye group of satyrs (genus Enodia) are rarely observed together at the same site at the same time. This report documents an occurrence of Enodia anthedon, E. portlandia, and E. creola together at a location near Jamestown, Virginia, United States. Editor’s note: Enodia is now recognized as a subgenus of Lethe. 6. Pages 17-19 Atlides halesus (Cramer, 1777) (Lycaenidae: Theclinae) and American Mistletoe in Northern Virginia by Harry Pavulaan and Richard D. Ullrich Abstract Atlides halesus halesus (Great Purple Hairstreak) is documented from three sites in western Fairfax County, Virginia, United States. The host American Mistletoe (Phoradendron leucarpum) is widespread in this area, forming dense infestations on trees which certainly supports a resident population of the butterfly as evidenced by several records over a 13-year span

    Micronutrient malnutrition and wasting in adults with pulmonary tuberculosis with and without HIV co-infection in Malawi

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    BACKGROUND: Wasting and micronutrient malnutrition have not been well characterized in adults with pulmonary tuberculosis. We hypothesized that micronutrient malnutrition is associated with wasting and higher plasma human immunodeficiency virus (HIV) load in adults with pulmonary tuberculosis. METHODS: In a cross-sectional study involving 579 HIV-positive and 222 HIV-negative adults with pulmonary tuberculosis in Zomba, Malawi, anthropometry, plasma HIV load and plasma micronutrient concentrations (retinol, α-tocopherol, carotenoids, zinc, and selenium) were measured. The risk of micronutrient deficiencies was examined at different severity levels of wasting. RESULTS: Body mass index (BMI), plasma retinol, carotenoid and selenium concentrations significantly decreased by increasing tertile of plasma HIV load. There were no significant differences in plasma micronutrient concentrations between HIV-negative individuals and HIV-positive individuals who were in the lowest tertile of plasma HIV load. Plasma vitamin A concentrations <0.70 μmol/L occurred in 61%, and zinc and selenium deficiency occurred in 85% and 87% respectively. Wasting, defined as BMI<18.5 was present in 59% of study participants and was independently associated with a higher risk of low carotenoids, and vitamin A and selenium deficiency. Severe wasting, defined as BMI<16.0 showed the strongest associations with deficiencies in vitamin A, selenium and plasma carotenoids. CONCLUSIONS: These data demonstrate that wasting and higher HIV load in pulmonary tuberculosis are associated with micronutrient malnutrition

    Evolutionary-Optimized Photonic Network Structure in White Beetle Wing Scales.

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    Most studies of structural color in nature concern periodic arrays, which through the interference of light create color. The "color" white however relies on the multiple scattering of light within a randomly structured medium, which randomizes the direction and phase of incident light. Opaque white materials therefore must be much thicker than periodic structures. It is known that flying insects create "white" in extremely thin layers. This raises the question, whether evolution has optimized the wing scale morphology for white reflection at a minimum material use. This hypothesis is difficult to prove, since this requires the detailed knowledge of the scattering morphology combined with a suitable theoretical model. Here, a cryoptychographic X-ray tomography method is employed to obtain a full 3D structural dataset of the network morphology within a white beetle wing scale. By digitally manipulating this 3D representation, this study demonstrates that this morphology indeed provides the highest white retroreflection at the minimum use of material, and hence weight for the organism. Changing any of the network parameters (within the parameter space accessible by biological materials) either increases the weight, increases the thickness, or reduces reflectivity, providing clear evidence for the evolutionary optimization of this morphology.PXCT measurements were performed at the cSAXS beamline at the Swiss Light Source, Paul Scherrer Institut, Switzerland. The OMNY instrumentation was supported by the Swiss National Science Foundation SNSF (Funding scheme RQUIP, Project number 145056). This research was financially supported through the National Centre of Competence in Research Bio-Inspired Materials, the Adolphe Merkle Foundation (to B.D.W. and U.S.), a BBSRC David Phillips fellowship (BB/K014617/1), the European Research Council (ERC-2014-STG H2020 639088, to O.O. and S.V.), and the Ambizione program of the Swiss National Science Foundation SNSF (168223, to B.D.W.). The authors acknowledge support from the Winton Programme for the Physics of Sustainability

    a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma

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    Background Despite novel therapeutic agents, most multiple myeloma (MM) patients eventually relapse. Two large phase III trials have shown significantly improved response rates (RR) of lenalidomide/dexamethasone compared with placebo/dexamethasone in relapsed MM (RMM) patients. These results have led to the approval of lenalidomide for RMM patients and lenalidomide/dexamethasone has since become a widely accepted second-line treatment. Furthermore, in RMM patients consolidation with high-dose chemotherapy plus autologous stem cell transplantation has been shown to significantly increase progression free survival (PFS) as compared to cyclophosphamide in a phase III trial. The randomized prospective ReLApsE trial is designed to evaluate PFS after lenalidomide/dexamethasone induction, high-dose chemotherapy consolidation plus autologous stem cell transplantation and lenalidomide maintenance compared with the well-established lenalidomide/dexamethasone regimen in RMM patients. Methods/Design ReLApsE is a randomized, open, multicenter phase III trial in a planned study population of 282 RMM patients. All patients receive three lenalidomide/dexamethasone cycles and - in absence of available stem cells from earlier harvesting - undergo peripheral blood stem cell mobilization and harvesting. Subsequently, patients in arm A continue on consecutive lenalidomide/dexamethasone cycles, patients in arm B undergo high dose chemotherapy plus autologous stem cell transplantation followed by lenalidomide maintenance until discontinuation criteria are met. Therapeutic response is evaluated after the 3rd (arm A + B) and the 5th lenalidomide/dexamethasone cycle (arm A) or 2 months after autologous stem cell transplantation (arm B) and every 3 months thereafter (arm A + B). After finishing the study treatment, patients are followed up for survival and subsequent myeloma therapies. The expected trial duration is 6.25 years from first patient in to last patient out. The primary endpoint is PFS, secondary endpoints include overall survival (OS), RR, time to best response and the influence of early versus late salvage high dose chemotherapy plus autologous stem cell transplantation on OS. Discussion This phase III trial is designed to evaluate whether high dose chemotherapy plus autologous stem cell transplantation and lenalidomide maintenance after lenalidomide/dexamethasone induction improves PFS compared with the well-established continued lenalidomide/dexamethasone regimen in RMM patients. Trial registration: ISRCTN16345835 (date of registration 2010-08-24)

    Preparation of Single-Phase Films of CH3NH3Pb(I1-xBrx)3 with Sharp Optical Band Edges.

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    Organometallic lead-halide perovskite-based solar cells now approach 18% efficiency. Introducing a mixture of bromide and iodide in the halide composition allows tuning of the optical bandgap. We prepare mixed bromide-iodide lead perovskite films CH3NH3Pb(I1-xBrx)3 (0 ≤ x ≤ 1) by spin-coating from solution and obtain films with monotonically varying bandgaps across the full composition range. Photothermal deflection spectroscopy, photoluminescence, and X-ray diffraction show that following suitable fabrication protocols these mixed lead-halide perovskite films form a single phase. The optical absorption edge of the pure triiodide and tribromide perovskites is sharp with Urbach energies of 15 and 23 meV, respectively, and reaches a maximum of 90 meV for CH3NH3PbI1.2Br1.8. We demonstrate a bromide-iodide lead perovskite film (CH3NH3PbI1.2Br1.8) with an optical bandgap of 1.94 eV, which is optimal for tandem cells of these materials with crystalline silicon devices.We acknowledge funding from the Engineering and Physical Sciences Research Council (EPSRC) and the Winton Programme (Cambridge) for the Physics of Sustainability. THT acknowledges funding from Cambridge Australia Scholarships and the Cambridge Commonwealth Trust. D.C. acknowledges support from St. John's College Cambridge and the Winton Programme (Cambridge) for the Physics of Sustainability.This is the final published version. It's also available at: http://pubs.acs.org/doi/abs/10.1021/jz501332v

    Structural Basis for Variant-Specific Neuroligin-Binding by α-Neurexin

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    Neurexins (Nrxs) are presynaptic membrane proteins with a single membrane-spanning domain that mediate asymmetric trans-synaptic cell adhesion by binding to their postsynaptic receptor neuroligins. α-Nrx has a large extracellular region comprised of multiple copies of laminin, neurexin, sex-hormone-binding globulin (LNS) domains and epidermal growth factor (EGF) modules, while that of β-Nrx has but a single LNS domain. It has long been known that the larger α-Nrx and the shorter β-Nrx show distinct binding behaviors toward different isoforms/variants of neuroligins, although the underlying mechanism has yet to be elucidated. Here, we describe the crystal structure of a fragment corresponding to the C-terminal one-third of the Nrx1α ectodomain, consisting of LNS5-EGF3-LNS6. The 2.3 Å-resolution structure revealed the presence of a domain configuration that was rigidified by inter-domain contacts, as opposed to the more common flexible “beads-on-a-string” arrangement. Although the neuroligin-binding site on the LNS6 domain was completely exposed, the location of the α-Nrx specific LNS5-EGF3 segment proved incompatible with the loop segment inserted in the B+ neuroligin variant, which explains the variant-specific neuroligin recognition capability observed in α-Nrx. This, combined with a low-resolution molecular envelope obtained by a single particle reconstruction performed on negatively stained full-length Nrx1α sample, allowed us to derive a structural model of the α-Nrx ectodomain. This model will help us understand not only how the large α-Nrx ectodomain is accommodated in the synaptic cleft, but also how the trans-synaptic adhesion mediated by α- and β-Nrxs could differentially affect synaptic structure and function
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