487 research outputs found

    Massive investments in bike infrastructure have got more people moving in Memphis, but they have also affected social inequality

    Get PDF
    In the past six years Memphis, Tennessee has undergone a cycling revolution, creating more than 100 miles of bicycle lanes and greenways. Despite the beneficial environmental implications of such a scheme, is bike oriented development just a way of reinforcing the status quo of social inequality? Kevin T. Smiley, Wanda Rushing, and Michele Scott find that while such bike schemes are likely to spur economic development and raise property values, these economic benefits are most likely to go to developers and may result in further racialized gentrification

    A Workflow for Lipid Nanoparticle (LNP) Formulation Optimization Using Designed Mixture-Process Experiments and Self-Validated Ensemble Models (SVEM)

    Full text link
    We present a Quality by Design (QbD) styled approach for optimizing lipid nanoparticle (LNP) formulations, aiming to offer scientists an accessible workflow. The inherent restriction in these studies, where the molar ratios of ionizable, helper, and PEG lipids must add up to 100%, requires specialized design and analysis methods to accommodate this mixture constraint. Focusing on lipid and process factors that are commonly used in LNP design optimization, we provide steps that avoid many of the difficulties that traditionally arise in the design and analysis of mixture-process experiments by employing space-filling designs and utilizing the recently developed statistical framework of self-validated ensemble models (SVEM). In addition to producing candidate optimal formulations, the workflow also builds graphical summaries of the fitted statistical models that simplify the interpretation of the results. The newly identified candidate formulations are assessed with confirmation runs and optionally can be conducted in the context of a more comprehensive second-phase study

    Translocating Wild California Valley Quail to Texas: An Evaluation of Survival, Dispersal, Tracking Efficacy, and Roost Preference

    Get PDF
    Quail translocations are becoming increasingly popular in regions of suitable habitat where local quail populations have declined. In northeastern Texas, USA, northern bobwhite (Colinus virginianus) populations have drastically declined for over a century and have reached undetectable levels in many areas. As a result, the number of quail hunters and quail conservation funding have also declined. California valley quail (Callipepla californica; hereafter, valley quail) have increased across their range and have been translocated to many states and countries. Thus, the goal of this study was to determine whether translocating wild valley quail to Texas was feasible, and evaluate their survival, dispersal, roost location preference, and potential predator impacts. We translocated 748 wild valley quail from Idaho, USA to northeastern Texas in 2019 and 2020. We collected quail location data from very high frequency (VHF) and digital transmitters. Motion-triggered cameras, scent stations, simulated nests, and raptor transects were used to record predator presence and potential predator impacts. Survival of birds with tracking devices was 63% (VHF) in 2019, and 38.8% (VHF) and 92.5% (digital tag) in 2020. Survival was greater for quail with digital transmitters. Median dispersal distance was 633.5 m in 2019 and 246.6 m in 2020 for valley quail with VHF transmitters, and 310.4 m for quail with digital transmitters. Minimum convex polygon area medians were 4.3 ha in 2019 and 3.1 ha in 2020 for quail with VHF transmitters, and 16.1 ha in 2020 for quail with digital transmitters. Roost sites were primarily in young stands of oak trees. Median simulated nest survival was 2 days (minimum [min] = 1, interquartile range [IQR] = 2–5.4, maximum [max] = 23) in 2019, and 7.5 days (min = 2, IQR = 4.5–15.2, max = 23) in 2020. The most frequent mammalian predators observed were raccoons (Procyon lotor), feral hogs (Sus scrofa), and white-tailed deer (Odocoileus virginianus). Red-tailed hawks (Buteo jamaicensis) were the most frequent aerial predator. We completed the first documented translocation of wild California valley quail to Texas, demonstrating it is feasible. Future translocation may benefit from translocating more birds over a longer period of time, with more consistent methodology. The establishment of a sustainable population may require ≥7 years of translocation at a rate of 500 birds per year with \u3e2,000 ha of suitable habitat

    Mechanical Effects of Rice Hush Ash in Ultra-High Performance Concretes: A Matrix Study,

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/84784/1/stults-RHA-2009.pd

    The Strength of Migratory Connectivity for Birds En Route to Breeding Through the Gulf of Mexico

    Get PDF
    The strength of migratory connectivity is a measure of the cohesion of populations among phases of the annual cycle, including breeding, migration, and wintering. Many Nearctic‐Neotropical species have strong migratory connectivity between breeding and wintering phases of the annual cycle. It is less clear if this strength persists during migration when multiple endogenous and exogenous factors may decrease the cohesion of populations among routes or through time along the same routes. We sampled three bird species, American redstart Setophaga ruticilla, ovenbird Seiurus aurocapilla, and wood thrush Hylocichla mustelina, during spring migration through the Gulf of Mexico region to test if breeding populations differentiate spatially among migration routes or temporally along the same migration routes and the extent to which within‐population timing is a function of sex, age, and carry‐over from winter habitat, as measured by stable carbon isotope values in claws (δ13C). To make quantitative comparisons of migratory connectivity possible, we developed and used new methodology to estimate the strength of migratory connectivity (MC) from probabilistic origin assignments identified using stable hydrogen isotopes in feathers (δ2H). We found support for spatial differentiation among routes by American redstarts and ovenbirds and temporal differentiation along routes by American redstarts. After controlling for breeding origin, the timing of American redstart migration differed among ages and sexes and ovenbird migration timing was influenced by carry‐over from winter habitat. The strength of migratory connectivity did not differ among the three species, with each showing weak breeding‐to‐spring migration MC relative to prior assessments of breeding‐wintering connectivity. Our work begins to fill an essential gap in methodology and understanding of the extent to which populations remain together during migration, information critical for a full annual cycle perspective on the population dynamics and conservation of migratory animals

    Dysferlinopathy in Switzerland: clinical phenotypes and potential founder effects.

    Get PDF
    BACKGROUND: Dysferlin is reduced in patients with limb girdle muscular dystrophy type 2B, Miyoshi myopathy, distal anterior compartment myopathy, and in certain Ethnic clusters. METHODS: We evaluated clinical and genetic patient data from three different Swiss Neuromuscular Centers. RESULTS: Thirteen patients from 6 non-related families were included. Age of onset was 18.8 ± 4.3 years. In all patients, diallelic disease-causing mutations were identified in the DYSF gene. Nine patients from 3 non-related families from Central Switzerland carried the identical homozygous mutation, c.3031 + 2 T>C. A possible founder effect was confirmed by haplotype analysis. Three patients from two different families carried the heterozygous mutation, c.1064_1065delAA. Two novel mutations were identified (c.2869 C>T (p.Gln957Stop), c.5928 G>A (p.Trp1976Stop)). CONCLUSIONS: Our study confirms the phenotypic heterogeneity associated with DYSF mutations. Two mutations (c.3031 + 2 T>C, c.1064_1065delAA) appear common in Switzerland. Haplotype analysis performed on one case (c. 3031 + 2 T>C) suggested a possible founder effect

    Possible new Arkansas endemic plant revealed by DNA sequence analysis, A

    Get PDF
    Cardamine angustata var. ouachitana, a wildflower in the mustard family (Brassicaceae), was described by Smith in 1982 to include a form of Cardamine found only in the Ouachita Mountains of Arkansas. This variety is morphologically very similar to typical Cardamine angustata. The major difference noted by Smith for the two varieties was the complete lack of leaf hairs (trichomes) in the new variety, whereas typical Cardamine angustata normally possesses trichomes. However, Al-Shehbaz rejected the variety ouachitana and reduced it to synonymy with the typical C. angustata. The recommendation of Al-Shehbaz has been followed and the taxon Cardamine angustata var. ouachitana is currently not accepted by most plant taxonomists. We performed a preliminary evaluation of the status of Cardamine angustata var. ouachitana by comparing ribosomal internal transcribed spacer region DNA sequences from specimens of Cardamine angustata var. ouachitana with sequences of Cardamine angustata from the main range of the species and other related species of Cardamine. Phylogenetic analyses of these data produced an unexpected result; specimens of C. angustata var. ouachitana were actually closely related to C. concatenata, rather than the expected close relationship with C. angustata. However, C. angustata var. ouachitana is morphologically distinct from C. concatenata. These results suggest that Cardamine angustata var. ouachitana is actually a new species found only in the Ouachita Mountains of Arkansas
    corecore