380 research outputs found

    Evaluating Downtown Dynamics

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    The goal of this thesis is to present an improved methodology for evaluating the overall quality of downtowns. The result is a set of Quality of Downtown Indicators that can be summarized by a comprehensive Quality of Downtown Index (QDI). This evaluation framework has three distinct advantages over current practice: It is comprehensive: Real estate professionals, demographers, economists and urban planners have differing concerns regarding urban places and thus evaluate places with different criteria. The QDI includes performance indicators used in all of these fields, organized by four key elements of a quality downtown: accessibility (urban form and transportation), economy (employment and real estate), community (downtown as a residential neighborhood) and identity (distinctiveness, culture and activity). It provides unprecedented geographic precision: A major shortcoming of existing downtown research is its dependence upon data collected at the census tract level. Census tracts are defined based on residential population, so downtowns with few residents have very large tracts. These coarse units are often a poor fit for downtown geographies. The QDI was developed for fine geographic precision; its indicators primarily use data available at point, parcel and block levels. It is transparent: This paper explains each step in the development of the QDI; it justifies the underlying assumptions behind each indicator of the index. It presents the sources where data for each indicator can be found, including the limitations of each data source. The next chapter presents a review of the literature that informed the assumptions and methodology of the QDI. Chapter 3 explains the key decisions that went into its development, including the geographic definition of downtown, the reasoning behind selected performance idnicators, and the process of constructing a composite index. Chapter 4 applies the methodology to two case cities in North Carolina and discusses how the results align with local perceptions of downtown change. The paper concludes by identifying areas for further research and potential improvements to the QDI and by describing potential applications for academics, professionals, policy-makers and the public.Bachelor of Art

    Large seeds provide an intrinsic growth advantage that depends on leaf traits and root allocation

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    1. Seed mass and growth rate are important dimensions of plant ecological diversity, but their relationship remains unresolved. Negative relationships between RGR and seed mass are well-established. However, RGR is size dependent, so small-seeded species might achieve fast growth simply because they are initially small. 2. Using a dataset of unprecedented size, sampling 382 grass species, we investigated seed mass and growth rate using both RGR and SGR (RGR at a specific size), accounting for diversity in phylogeny, ecology (e.g. life history, photosynthetic pathway) and environment (mean annual temperature and precipitation). 3. RGR and SGR showed contrasting relationships with seed mass, such that large-seeded species had lower RGR but higher SGR than small-seeded species. However, the relationship between SGR and seed mass depended on leaf dry matter content (LDMC), and was only positive in high-LDMC species. When compared at a common size, the fast growth of large-seeded and low-LDMC species was associated with greater biomass allocation to roots in the hot, high-light environment used for our experiment. Photosynthetic pathway and life history contributed to variation in SGR, with C4 annuals having higher SGRs than C3 perennials regardless of seed size. 4. Large seeds therefore afford an intrinsic growth advantage in species with resource-conserving leaf traits, and may provide a competitive edge in resource-poor environments. This work advances the understanding of how seed mass and growth rate co-evolve with other ecological factors

    The relationship between central Indian terrestrial vegetation and monsoon rainfall distributions in different hydroclimatic extreme years using time-series satellite data

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    The study explored the dependence of the spatio-temporal pattern of rainfall and its variability on the spatial distribution of forests in the central Indian landscape, which covers ~1 million km2, includes five states, and supports a population of 329 million people. The monsoon rainfall is, thus, a crucial source of freshwater for these population. We analyzed the relationship between rainfall and satellite-derived vegetation vigor, vegetation fraction, and elevation across 22 experimental zones across central India (i.e., forested, non-forested, and agricultural regions; buffer zones within and outside forests). Around 87% of annual rainfall is received during the monsoon, with maximum rainfall (~1600 mm) in Odisha and minimum (~900 mm) in Maharashtra. The average rainfall was greater (~1500 mm) inside forests than in non-forested regions (~1000 mm). Moreover, 245 mm km−2 year−1 of rainfall was observed over forests during monsoon, but only 215 mm km−2 year−1 in non-forested areas. Overall, rainfall increases from the forest edge towards the forest core logarithmically at a rate of ~10 mm km−1 year−1, and it decreases exponentially when moving away from the forest edge at an average rate of −20 mm km−1 year−1 over 0-to-50 km range, and at a rate of −7.5 mm km−1 year−1 over the 50-to-100 km range. This rate of decrease was maximum in Madhya Pradesh and Jharkhand and minimum in Chhattisgarh. The results confirmed the crucial role of forests in the distribution of monsoon rainfall, but in the elevated and Western Ghats regions, the orographic effect is dominant. These findings are of great concern to forest policymakers to conserve and protect the central Indian forests

    C4 photosynthesis and the economic spectra of leaf and root traits independently influence growth rates in grasses

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    1. Photosynthetic pathway is an important cause of growth rate variation between species, such that the enhanced carbon uptake of C4 species leads to faster growth than their C3 counterparts. Leaf traits that promote rapid resource acquisition may further enhance the growth capacity of C4 species. However, how root economic traits interact with leaf traits, and the different growth strategies adopted by plants with C3 and C4 photosynthetic pathways is unclear. Plant economic traits could interact with, or act independently of, photosynthetic pathway in influencing growth rate, or C3 and C4 species could segregate out along a common growth rate‐trait relationship. 2. We measured leaf and root traits on 100+ grass species grown from seeds in a controlled, common environment to compare with relative growth rates (RGR) during the initial phase of rapid growth, controlling for phylogeny and allometric effects. 3. Photosynthetic pathway acts independently to leaf and root functional traits in causing fast growth. Using C4 photosynthesis, plants can achieve faster growth than their C3 counterparts (by an average 0.04 g g‐1 day‐1) for a given suite of functional trait values, with lower investments of leaf and root nitrogen. Leaf and root traits had an additive effect on RGR, with plants achieving fast growth by possessing resource‐acquisitive leaf traits (high specific leaf area and low leaf dry matter content) or root traits (high specific root length and area, and low root diameter), but having both leads to an even faster growth rate (by up to 0.06 g g‐1 day‐1). C4 photosynthesis can provide a greater relative increase in RGR for plants with a ‘slow’ ecological strategy than in those with fast growth. However, aboveground and belowground strategies are not coordinated, so that species can have any combination of ‘slow’ or ‘fast’ leaf and root traits. 4. Synthesis: C4 photosynthesis increases growth rate for a given combination of economic traits, and significantly alters plant nitrogen economy in the leaves and roots. However, leaf and root economic traits act independently to further enhance growth. The fast growth of C4 grasses promotes a competitive advantage under hot, sunny conditions

    A pleurocidin analogue with greater conformational flexibility, enhanced antimicrobial potency and in vivo therapeutic efficacy.

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    Antimicrobial peptides (AMPs) are a potential alternative to classical antibiotics that are yet to achieve a therapeutic breakthrough for treatment of systemic infections. The antibacterial potency of pleurocidin, an AMP from Winter Flounder, is linked to its ability to cross bacterial plasma membranes and seek intracellular targets while also causing membrane damage. Here we describe modification strategies that generate pleurocidin analogues with substantially improved, broad spectrum, antibacterial properties, which are effective in murine models of bacterial lung infection. Increasing peptide-lipid intermolecular hydrogen bonding capabilities enhances conformational flexibility, associated with membrane translocation, but also membrane damage and potency, most notably against Gram-positive bacteria. This negates their ability to metabolically adapt to the AMP threat. An analogue comprising D-amino acids was well tolerated at an intravenous dose of 15 mg/kg and similarly effective as vancomycin in reducing EMRSA-15 lung CFU. This highlights the therapeutic potential of systemically delivered, bactericidal AMPs

    Effective knowledge translation approaches and practices in Indigenous health research: A systematic review protocol

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    Background: Effective knowledge translation (KT) is critical to implementing program and policy changes that require shared understandings of knowledge systems, assumptions, and practices. Within mainstream research institutions and funding agencies, systemic and insidious inequities, privileges, and power relationships inhibit Indigenous peoples' control, input, and benefits over research. This systematic review will examine literature on KT initiatives in Indigenous health research to help identify wise and promising Indigenous KT practices and language in Canada and abroad. Methods: Indexed databases including Aboriginal Health Abstract Database, Bibliography of Native North Americans, CINAHL, Circumpolar Health Bibliographic Database, Dissertation Abstracts, First Nations Periodical Index, Medline, National Indigenous Studies Portal, ProQuest Conference Papers Index, PsycInfo, Social Services Abstracts, Social Work Abstracts, and Web of Science will be searched. A comprehensive list of non-indexed and grey literature sources will also be searched. For inclusion, documents must be published in English; linked to Indigenous health and wellbeing; focused on Indigenous people; document KT goals, activities, and rationale; an

    Molecular and Historical Aspects of Corn Belt Dent Diversity

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    Tens-of-thousands of open-pollinated cultivars of corn (Zea mays L.) are being maintained in germplasm banks. Knowledge of the amount and distribution of genetic variation within and among accessions can aid end users in choosing among them. We estimated molecular genetic variation and looked for influences of pedigree, adaptation, and migration in the genetic makeup of conserved Corn-Belt Dent-related germplasm. Plants sampled from 57 accessions representing Corn-Belt Dents, Northern Flints, Southern Dents, plus 12 public inbreds, were genotyped at 20 simple sequence repeat (SSR) loci. For 47 of the accessions, between 5 and 23 plants per accession were genotyped (mean = 9.3). Mean number of alleles per locus was 6.5 overall, 3.17 within accessions, and 3.20 within pooled inbreds. Mean gene diversity was 0.53 within accessions and 0.61 within pooled inbreds. Open-pollinated accessions showed a tendency toward inbreeding (FIS = 0.09), and 85% of genetic variation was shared among them. A Fitch-Margoliash tree strongly supported the distinctiveness of flint from dent germplasm but did not otherwise reveal evidence of genetic structure. Mantel tests revealed significant correlations between genetic distance and geographical (r = 0.54, P= 0.04) or maturity zone (r = 0.33, P = 0.03) distance only if flint germplasm was included in the analyses. A significant correlation (r = 0.76, P \u3c 0.01) was found between days to pollen shed and maturity zone of accession origin. Pedigree, rather than migration or selection, has most influenced the genetic structure of the extant representatives of the open-pollinated cultivars at these SSR loci

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    India’s contribution to mitigating the impacts of climate change through vegetation management

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    The changes in natural ecosystems provide opportunity to increase vegetation carbon sink capacity and thereby contribute to mitigation of climate change impacts. The Indian tropics and the large ecological variation within the country afford the advantage of diverse niches and offer opportunities to reveal the role of biotic factors at different levels of organization from populations to ecosystems. The last 4 decades of research and development in the Indian space science community has been primarily application driven in response to the government space programme for national development. The expenditure in R&D over next 5 year suggest that scientific research is higher on the country's agenda. The Indo-UK Terrestrial Carbon Group (IUTCG) comprising both Indian and UK scientists, funded jointly by the Department of Science and Technology, India and the Department of Business, Innovation and Skills organised a workshop to explore ways in which Earth observation data can be effectively utilised in mitigating the impacts of climate change through vegetation management. Effective integration of field observations, collected through various monitoring networks, and satellite sensor data has been proposed to provide country-wide monitoring

    Measurement of the cross section of high transverse momentum Z→bb̄ production in proton–proton collisions at √s = 8 TeV with the ATLAS detector

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    This Letter reports the observation of a high transverse momentum Z→bb̄ signal in proton–proton collisions at √s=8 TeV and the measurement of its production cross section. The data analysed were collected in 2012 with the ATLAS detector at the LHC and correspond to an integrated luminosity of 19.5 fb−Âč. The Z→bb̄ decay is reconstructed from a pair of b -tagged jets, clustered with the anti-ktkt jet algorithm with R=0.4R=0.4, that have low angular separation and form a dijet with pT>200 GeVpT>200 GeV. The signal yield is extracted from a fit to the dijet invariant mass distribution, with the dominant, multi-jet background mass shape estimated by employing a fully data-driven technique that reduces the dependence of the analysis on simulation. The fiducial cross section is determined to be σZ→bbÂŻfid=2.02±0.20 (stat.) ±0.25 (syst.)±0.06 (lumi.) pb=2.02±0.33 pb, in good agreement with next-to-leading-order theoretical predictions
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