356 research outputs found
AGRICULTURAL LAND CONVERSION IN THE TWIN CITIES: PART II, THE NATIONAL RESOURCES INVENTORY
We divided the thirteen-county Twin Cities Metropolitan Statistical Area into a core and a fringe of seven and six counties, respectively. The National Resources Inventory estimates that 170 thousand acres of the Core were converted from agriculture to other uses between 1982 and 1987, while only about 46 thousand acres of the Fringe were so converted. The conversion rate was much greater in the Core than on the Fringe according to the NRIbut not according to the Census of Agriculture. The number of acres of agricultural land converted for each new resident ranged from 0.15 in Sherburne County to 2.49 in Pierce County. Viewed another way, the increase in urban land to house new residents ranged from 0.28 in Ramsey County to 1.23 acres per person in Isanti County.Land Economics/Use,
Tropical race 4: Current and future impact on export and subsistence banana production.
Norman Simmonds classified fusarium wilt of banana, caused by F. oxysporum f. sp. cubense (FOC), as one of the most destructive plant diseases. Susceptibility to race 1 of FOCdoomed 'Gros Michel,' the banana cultivar on which the first export trades were based; it was replaced by race 1-resistant Cavendish clones by the 19605.Trabalhos apresentados no: APS-IPPC 2011 Joint Meeting in Honolulu, Hawaii, August 6-10, 2011
A study of wrist-worn activity measurement as a potential real-world biomarker for late-life depression.
BACKGROUND: Late-life depression (LLD) is associated with a decline in physical activity. Typically this is assessed by self-report questionnaires and, more recently, with actigraphy. We sought to explore the utility of a bespoke activity monitor to characterize activity profiles in LLD more precisely. METHOD: The activity monitor was worn for 7 days by 29 adults with LLD and 30 healthy controls. Subjects underwent neuropsychological assessment and quality of life (QoL) (36-item Short-Form Health Survey) and activities of daily living (ADL) scales (Instrumental Activities of Daily Living Scale) were administered. RESULTS: Physical activity was significantly reduced in LLD compared with controls (t = 3.63, p < 0.001), primarily in the morning. LLD subjects showed slower fine motor movements (t = 3.49, p < 0.001). In LLD patients, activity reductions were related to reduced ADL (r = 0.61, p < 0.001), lower QoL (r = 0.65, p < 0.001), associative learning (r = 0.40, p = 0.036), and higher Montgomery-Åsberg Depression Rating Scale score (r = -0.37, p < 0.05). CONCLUSIONS: Patients with LLD had a significant reduction in general physical activity compared with healthy controls. Assessment of specific activity parameters further revealed the correlates of impairments associated with LLD. Our study suggests that novel wearable technology has the potential to provide an objective way of monitoring real-world function.This study was funded by an award from the UK
Medical Research Council (G1001828/1)
Fluctuation solution theory of pure fluids
Citation: Ploetz, E. A., Pallewela, G. N., & Smith, P. E. (2017). Fluctuation solution theory of pure fluids. Journal of Chemical Physics, 146(9), 13. doi:10.1063/1.4977040Fluctuation Solution Theory (FST) provides an alternative view of fluid thermodynamics in terms of pair fluctuations in the particle number and excess energy observed for an equivalent open system. Here we extend the FST approach to provide a series of triplet and quadruplet particle and excess energy fluctuations that can also be used to help understand the behavior of fluids. The fluctuations for the gas, liquid, and supercritical regions of three fluids (H2O, CO2, and SF6) are then determined from accurate equations of state. Many of the fluctuating quantities change sign on moving from the gas to liquid phase and, therefore, we argue that the fluctuations can be used to characterize gas and liquid behavior. Further analysis provides an approach to isolate contributions to the excess energy fluctuations arising from just the intermolecular interactions and also indicates that the triplet and quadruplet particle fluctuations are related to the pair particle fluctuations by a simple power law for large regions of the phase diagram away from the critical point. Published by AIP Publishing
Experimental triplet and quadruplet fluctuation densities and spatial distribution function integrals for pure liquids
Citation: Ploetz, E. A., Karunaweera, S., & Smith, P. E. (2015). Experimental triplet and quadruplet fluctuation densities and spatial distribution function integrals for pure liquids. Journal of Chemical Physics, 142(4), 14. doi:10.1063/1.4905562Fluctuation solution theory has provided an alternative view of many liquid mixture properties in terms of particle number fluctuations. The particle number fluctuations can also be related to integrals of the corresponding two body distribution functions between molecular pairs in order to provide a more physical picture of solution behavior and molecule affinities. Here, we extend this type of approach to provide expressions for higher order triplet and quadruplet fluctuations, and thereby integrals over the corresponding distribution functions, all of which can be obtained from available experimental thermodynamic data. The fluctuations and integrals are then determined using the International Association for the Properties of Water and Steam Formulation 1995 (IAPWS-95) equation of state for the liquid phase of pure water. The results indicate small, but significant, deviations from a Gaussian distribution for the molecules in this system. The pressure and temperature dependence of the fluctuations and integrals, as well as the limiting behavior as one approaches both the triple point and the critical point, are also examined. (C) 2015 AIP Publishing LLC
The TANAMI Program
TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond
Interferometry) is a monitoring program to study the parsec-scale structures
and dynamics of relativistic jets in active galactic nuclei (AGN) of the
Southern Hemisphere with the Long Baseline Array and associated telescopes.
Extragalactic jets south of -30 degrees declination are observed at 8.4 GHz and
22 GHz every two months at milliarcsecond resolution. The initial TANAMI sample
is a hybrid radio and gamma-ray selected sample since the combination of VLBI
and gamma-ray observations is crucial to understand the broadband emission
characteristics of AGN.Comment: Confernce Proceedings for "X-ray Astronomy 2009" (Bologna), 3 pages,
3 figures, needs cls-fil
Micelles of Polybutadiene-b-Poly(Ethylene Oxide) in a Binary Solvent System
We studied the assembly behavior of a polybutadiene-b-poly(ethylene oxide) diblock copolymer in methanol, cyclohexane, and the corresponding partially miscible binary solvent system. Dynamic light scattering indicates that the copolymer forms coexisting spherical and cylindrical micelles in both of the pure solvents. In the binary solvent system, spherical micelles form in the methanol-rich phase for a wide range of temperatures. Conversely, micelles are present in the cyclohexane-rich phase only near the critical temperature. At the critical solvent composition, micelles form in the single phase region above the critical temperature. Size exclusion chromatography results for the binary solvent system show that the copolymer generally prefers the methanol-rich phase. The preference becomes more pronounced as temperature decreases
Recent advances in understanding the roles of whole genome duplications in evolution
Ancient whole-genome duplications (WGDs)—paleopolyploidy events—are key to solving Darwin’s ‘abominable mystery’ of how flowering plants evolved and radiated into a rich variety of species. The vertebrates also emerged from their invertebrate ancestors via two WGDs, and genomes of diverse gymnosperm trees, unicellular eukaryotes, invertebrates, fishes, amphibians and even a rodent carry evidence of lineage-specific WGDs. Modern polyploidy is common in eukaryotes, and it can be induced, enabling mechanisms and short-term cost-benefit assessments of polyploidy to be studied experimentally. However, the ancient WGDs can be reconstructed only by comparative genomics: these studies are difficult because the DNA duplicates have been through tens or hundreds of millions of years of gene losses, mutations, and chromosomal rearrangements that culminate in resolution of the polyploid genomes back into diploid ones (rediploidisation). Intriguing asymmetries in patterns of post-WGD gene loss and retention between duplicated sets of chromosomes have been discovered recently, and elaborations of signal transduction systems are lasting legacies from several WGDs. The data imply that simpler signalling pathways in the pre-WGD ancestors were converted via WGDs into multi-stranded parallelised networks. Genetic and biochemical studies in plants, yeasts and vertebrates suggest a paradigm in which different combinations of sister paralogues in the post-WGD regulatory networks are co-regulated under different conditions. In principle, such networks can respond to a wide array of environmental, sensory and hormonal stimuli and integrate them to generate phenotypic variety in cell types and behaviours. Patterns are also being discerned in how the post-WGD signalling networks are reconfigured in human cancers and neurological conditions. It is fascinating to unpick how ancient genomic events impact on complexity, variety and disease in modern life
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