2,496 research outputs found

    Enumerating Segmented Patterns in Compositions and Encoding by Restricted Permutations

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    A composition of a nonnegative integer (n) is a sequence of positive integers whose sum is (n). A composition is palindromic if it is unchanged when its terms are read in reverse order. We provide a generating function for the number of occurrences of arbitrary segmented partially ordered patterns among compositions of (n) with a prescribed number of parts. These patterns generalize the notions of rises, drops, and levels studied in the literature. We also obtain results enumerating parts with given sizes and locations among compositions and palindromic compositions with a given number of parts. Our results are motivated by "encoding by restricted permutations," a relatively undeveloped method that provides a language for describing many combinatorial objects. We conclude with some examples demonstrating bijections between restricted permutations and other objects.Comment: 12 pages, 1 figur

    SLIDES: Tightening Water Supplies: Key Colorado River Issues for Wyoming

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    Presenter: Patrick T. Tyrrell, Wyoming State Engineer. 14 slides

    SLIDES: Tightening Water Supplies: Key Colorado River Issues for Wyoming

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    Presenter: Patrick T. Tyrrell, Wyoming State Engineer. 14 slides

    A quantified triple bottom line for tourism: experimental results

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    The tradition of tourism businesses and regional tourism industries is to measure their value to the host community by jobs, wages and tax revenues even though every member of that community is impacted on a daily basis though a broad variety of impacts. This paper demonstrates a conceptual approach for measuring the relative importance of the major dimensions of community quality of life that can be influenced by the tourism industry in order to calculate an indication of overall impact on the well being of community residents. Furthermore, we have formulated a conjoint model that values this overall performance in monetary units. A conjoint model for estimating importance is successfully implemented using samples of college students and tourism industry professionals in the US and Cyprus. A monetary version of Triple Bottom Line impacts is calculated for the impacts of a specific hypothetical tourism business development

    Evaluating tourism community preferences

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    A short online survey of Kingman Arizona residents included two approaches for determining the relative importance of social, cultural, environmental, and economic attributes to community quality of life. A simple multiattribute choice approach gave noticeably different results from a standard independent attribute ranking approach and lead researchers to recommend socially oriented tourism development projects over economically oriented ones

    A mixed life-cycle stage bloom of Syracosphaera bannockii (Borsetti and Cati, 1976) Cros et al. 2000 (Bay of Biscay, April 2010)

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    High concentrations (464 cells mL-1) of Syracosphaera bannockii have been identified for the first time, in the Bay of Biscay during April 2010. These high concentrations combined with coccolithophore community dominance (~87%) indicated that a bloom of S. bannockii had formed. While the bloom consisted mostly of heterococcolith coccospheres, both holococcolith coccospheres and holococcolith-heterococcolith combination coccospheres were observed. This is only the second time that combination coccospheres of S. bannockii have been observed

    New Forces Influencing Savanna Conservation: Increasing Land Prices Driven by Gentrification and Speculation at the Landscape Scale

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    Land transformation reduces biodiversity and regional sustainability, with land price being an indicator of the opportunity cost to a landowner of resisting land conversion. However, reliable spatially explicit databases of current land prices are generally lacking in developing countries. We used tools from data science to scrape 1,487 georeferenced land prices in southern Kenya from the internet. Prices were higher for land near cities and in areas of high agricultural productivity, but also around the Maasai Mara National Reserve. Predicted land prices ranged from US662toUS662 to US4,618,805 per acre. Land speculation associated with expanding urbanization increases the opportunity and acquisition costs of maintaining conservation buffer zones, corridors, and dispersal areas. However, high land values are also found adjacent to a world-famous tourist destination. Profit-driven turnover of ownership, subdivision, and transformation of land is occurring at a rapid pace in southern Kenya, to the detriment of savanna biodiversity and the sustainability of the pastoral social–ecological system

    Parental diabetes and birthweight in 236 030 individuals in the UK biobank study

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    This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.BACKGROUND: The UK Biobank study provides a unique opportunity to study the causes and consequences of disease. We aimed to use the UK Biobank data to study the well-established, but poorly understood, association between low birthweight and type 2 diabetes. METHODS: We used logistic regression to calculate the odds ratio for participants' risk of type 2 diabetes given a one standard deviation increase in birthweight. To test for an association between parental diabetes and birthweight, we performed linear regression of self-reported parental diabetes status against birthweight. We performed path and mediation analyses to test the hypothesis that birthweight partly mediates the association between parental diabetes and participant type 2 diabetes status. RESULTS: Of the UK Biobank participants, 277 261 reported their birthweight. Of 257 715 individuals of White ethnicity and singleton pregnancies, 6576 had type 2 diabetes, 19 478 reported maternal diabetes (but not paternal), 20 057 reported paternal diabetes (but not maternal) and 2754 participants reported both parents as having diabetes. Lower birthweight was associated with type 2 diabetes in the UK Biobank participants. A one kilogram increase in birthweight was associated with a lower risk of type 2 diabetes (odds ratio: 0.74; 95% CI: 0.71, 0.76; P = 2 × 10(-57)). Paternal diabetes was associated with lower birthweight (45 g lower; 95% CI: 36, 54; P = 2 × 10(-23)) relative to individuals with no parental diabetes. Maternal diabetes was associated with higher birthweight (59 g increase; 95% CI: 50, 68; P = 3 × 10(-37)). Participants' lower birthweight was a mediator of the association between reported paternal diabetes and participants' type 2 diabetes status, explaining 1.1% of the association, and participants' higher birthweight was a mediator of the association between reported maternal diabetes and participants' type 2 diabetes status, explaining 1.2% of the association. CONCLUSIONS: Data from the UK Biobank provides the strongest evidence by far that paternal diabetes is associated with lower birthweight, whereas maternal diabetes is associated with increased birthweight. Our findings with paternal diabetes are consistent with a role for the same genetic factors influencing foetal growth and type 2 diabetes.ERDF (European Regional Development Fund)ESF (European Social Fund) Convergence Programme for Cornwall and the Isles of ScillyWellcome TrustThe European Research CouncilDiabetes U

    Effect of enhanced pCO2 levels on the production of dissolved organic carbon and transparent exopolymer particles in short-term bioassay experiments

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    It has been proposed that increasing levels of pCO(2) in the surface ocean will lead to more partitioning of the organic carbon fixed by marine primary production into the dissolved rather than the particulate fraction. This process may result in enhanced accumulation of dissolved organic carbon (DOC) in the surface ocean and/or concurrent accumulation of transparent exopolymer particles (TEPs), with important implications for the functioning of the marine carbon cycle. We investigated this in shipboard bioassay experiments that considered the effect of four different pCO(2) scenarios (ambient, 550, 750 and 1000 mu atm) on unamended natural phytoplankton communities from a range of locations in the northwest European shelf seas. The environmental settings, in terms of nutrient availability, phytoplankton community structure and growth conditions, varied considerably between locations. We did not observe any strong or consistent effect of pCO(2) on DOC production. There was a significant but highly variable effect of pCO(2) on the production of TEPs. In three of the five experiments, variation of TEP production between pCO(2) treatments was caused by the effect of pCO(2) on phytoplankton growth rather than a direct effect on TEP production. In one of the five experiments, there was evidence of enhanced TEP production at high pCO(2) (twice as much production over the 96 h incubation period in the 750 mu atm treatment compared with the ambient treatment) independent of indirect effects, as hypothesised by previous studies. Our results suggest that the environmental setting of experiments (community structure, nutrient availability and occurrence of phytoplankton growth) is a key factor determining the TEP response to pCO(2) perturbations
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