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    Separation of Relatively Quasiconvex Subgroups

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    Suppose that all hyperbolic groups are residually finite. The following statements follow: In relatively hyperbolic groups with peripheral structures consisting of finitely generated nilpotent subgroups, quasiconvex subgroups are separable; Geometrically finite subgroups of non-uniform lattices in rank one symmetric spaces are separable; Kleinian groups are subgroup separable. We also show that LERF for finite volume hyperbolic 3-manifolds would follow from LERF for closed hyperbolic 3-manifolds. The method is to reduce, via combination and filling theorems, the separability of a quasiconvex subgroup of a relatively hyperbolic group G to the separability of a quasiconvex subgroup of a hyperbolic quotient G/N. A result of Agol, Groves, and Manning is then applied.Comment: 22 pages, 2 figures. New version has numbering matching with the published version in the Pacific Journal of Mathematics, 244 no. 2 (2010) 309--334

    Interprofessional Collaboration to Prevent Hospital-Acquired Pneumonia (HAP)

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    https://scholarworks.moreheadstate.edu/student_scholarship_posters/1138/thumbnail.jp

    What Do People Mean When They Say They “Had Sex”? Connecting Communication and Behavior

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    What do people mean when they say they “had sex”? The most-cited study regarding what activities are communicated as having “had sex” is now over 20 years old. This chapter provides findings from a study that replicated the original study’s methods to provide an up-to-date understanding. An Internet survey completed by 380 women and 197 men from the United States was conducted. Results show that penile-vaginal intercourse was the sexual activity most likely to count as having “had sex,” with 97.4% of participants indicating it as sex. Other common sexual activities measured include penile-anal intercourse, oral-genital contact, and manual stimulation of genitals. The findings suggest many attitudes represented in the original survey have changed. Implications and future studies are offered

    Continuous measurements of greenhouse gases and atmospheric oxygen at the Namib Desert atmospheric observatory

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    A new coastal background site has been established for observations of greenhouse gases (GHGs) in the central Namib Desert at Gobabeb, Namibia. The location of the site was chosen to provide observations for a data-poor region in the global sampling network for GHGs. Semi-automated continuous measurements of carbon dioxide, methane, nitrous oxide, carbon monoxide, atmospheric oxygen, and basic meteorology are made at a height of 21 m a.g.l., 50 km from the coast at the northern border of the Namib Sand Sea. Atmospheric oxygen is measured with a differential fuel cell analyzer (DFCA). Carbon dioxide and methane are measured with an early-model cavity ring-down spectrometer (CRDS); nitrous oxide and carbon monoxide are measured with an off-axis integrated cavity output spectrometer (OA-ICOS). Instrument-specific water corrections are employed for both the CRDS and OA-ICOS instruments in lieu of drying. The performance and measurement uncertainties are discussed in detail. As the station is located in a remote desert environment, there are some particular challenges, namely fine dust, high diurnal temperature variability, and minimal infrastructure. The gas handling system and calibration scheme were tailored to best fit the conditions of the site. The CRDS and DFCA provide data of acceptable quality when base requirements for operation are met, specifically adequate temperature control in the laboratory and regular supply of electricity. In the case of the OA-ICOS instrument, performance is significantly improved through the implementation of a drift correction through frequent measurements of a reference cylinder

    Polymyalgia rheumatica shows metabolomic alterations that are further altered by glucocorticoid treatment:Identification of metabolic correlates of fatigue

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    OBJECTIVE: In polymyalgia rheumatica (PMR), glucocorticoids (GCs) relieve pain and stiffness, but fatigue may persist. We aimed to explore the effect of disease, GCs and PMR symptoms in the metabolite signatures of peripheral blood from patients with PMR or the related disease, giant cell arteritis (GCA).METHODS: Nuclear magnetic resonance spectroscopy was performed on serum from 40 patients with untreated PMR, 84 with new-onset confirmed GCA, and 53 with suspected GCA who later were clinically confirmed non-GCA, and 39 age-matched controls. Further samples from PMR patients were taken one and six months into glucocorticoid therapy to explore relationship of metabolites to persistent fatigue. 100 metabolites were identified using Chenomx and statistical analysis performed in SIMCA-P to examine the relationship between metabolic profiles and, disease, GC treatment or symptoms.RESULTS: The metabolite signature of patients with PMR and GCA differed from that of age-matched non-inflammatory controls (R2 &gt; 0.7). There was a smaller separation between patients with clinically confirmed GCA and those with suspected GCA who later were clinically confirmed non-GCA (R2 = 0.135). In PMR, metabolite signatures were further altered with glucocorticoid treatment (R2 = 0.42) but did not return to that seen in controls. Metabolites correlated with CRP, pain, stiffness, and fatigue (R 2 ≄ 0.39). CRP, pain, and stiffness declined with treatment and were associated with 3-hydroxybutyrate and acetoacetate, but fatigue did not. Metabolites differentiated patients with high and low fatigue both before and after treatment (R2 &gt; 0.9). Low serum glutamine was predictive of high fatigue at both time points (0.79-fold change). CONCLUSION: PMR and GCA alter the metabolite signature. In PMR, this is further altered by glucocorticoid therapy. Treatment-induced metabolite changes were linked to measures of inflammation (CRP, pain and stiffness), but not to fatigue. Furthermore, metabolite signatures distinguished patients with high or low fatigue.</p

    Slope water intrusions onto Georges Bank

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    Author Posting. © American Geophysical Union, 2003. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 108, C11 (2003): 8012, doi:10.1029/2002JC001400.Data from moored instruments and hydrographic cruises of the U.S. GLOBEC NW Atlantic/Georges Bank program reveal a series of intrusions of high-salinity water extending onto the southern flank of Georges Bank during the spring and summer of 1995. On the basis of the layer of maximum salinity, these intrusions may be divided into three different types: near surface, near bottom, and pycnocline. The water mass and flow structure of all intrusions are highly variable, owing partly to wind-driven motions and partly to meanders and eddies formed along the front of the intruding water. The mooring data of May clearly show the passage of two cyclonic features, each with a core of intruding water. While the intrusions are shown to dominate the flux of high-salinity water onto the southern flank, the data examined offer no evidence that intrusions enhance nutrient concentrations over the southern flank.The work carried out at WHOI was supported by the U.S. National Science Foundation under grants OCE-98-06498, OCE-96-32357, OCE98-06397, and OCE02-27679. The effort at the Woods Hole NMFS was funded through a grant from the NOAA Coastal Ocean Program

    Erosion characteristics and horizontal variability for small erosion depths in the Sacramento-San Joaquin River Delta, California, USA

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    Erodibility of cohesive sediment in the Sacramento-San Joaquin River Delta (Delta) was investigated with an erosion microcosm. Erosion depths in the Delta and in the microcosm were estimated to be about one floc diameter over a range of shear stresses and times comparable to half of a typical tidal cycle. Using the conventional assumption of horizontally homogeneous bed sediment, data from 27 of 34 microcosm experiments indicate that the erosion rate coefficient increased as eroded mass increased, contrary to theory. We believe that small erosion depths, erosion rate coefficient deviation from theory, and visual observation of horizontally varying biota and texture at the sediment surface indicate that erosion cannot solely be a function of depth but must also vary horizontally. We test this hypothesis by developing a simple numerical model that includes horizontal heterogeneity, use it to develop an artificial time series of suspended-sediment concentration (SSC) in an erosion microcosm, then analyze that time series assuming horizontal homogeneity. A shear vane was used to estimate that the horizontal standard deviation of critical shear stress was about 30% of the mean value at a site in the Delta. The numerical model of the erosion microcosm included a normal distribution of initial critical shear stress, a linear increase in critical shear stress with eroded mass, an exponential decrease of erosion rate coefficient with eroded mass, and a stepped increase in applied shear stress. The maximum SSC for each step increased gradually, thus confounding identification of a single well-defined critical shear stress as encountered with the empirical data. Analysis of the artificial SSC time series with the assumption of a homogeneous bed reproduced the original profile of critical shear stress, but the erosion rate coefficient increased with eroded mass, similar to the empirical data. Thus, the numerical experiment confirms the small-depth erosion hypothesis. A linear model of critical shear stress and eroded mass is proposed to simulate small-depth erosion, assuming that the applied and critical shear stresses quickly reach equilibrium

    Atrial natriuretic factor

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    The discovery of the first well-defined natriuretic hormone, the Atrial Natriuretic Factor (ANF), has prompted research on its impact on volume regulation in health and disease. The natriuretic, diuretic, and smooth muscle-relaxing properties suggest an important role of this novel hormone in pathophysiological states with sodium or volume retention, such as congestive heart failure or cirrhosis of the liver. Investigations on the implications of ANF in liver disease have been performed for little more than 1 year, and results are still controversial in many respects. At present, it seems very likely that there is no absolute deficiency of plasma ANF in patients with cirrhosis. Moreover, elevated plasma levels in cirrhotics with ascites have been reported by several groups. However, as yet, a molecular characterization of this increased immunoreactivity is still lacking. There is disagreement on the reduced release of and renal response to ANF in subgroups of cirrhotics; however, stimulus-response-coupling might be impaired. Further studies are needed to elucidate the pathophysiological implications and therapeutical potential of ANF in patients with chronic liver disease

    Parameters influencing the regeneration of a green roof’s retention capacity via evapotranspiration

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    The extent to which the finite hydrological capacity of a green roof is available for retention of a storm event largely determines the scale of its contribution as a Sustainable Drainage System (SuDS). Evapotranspiration (ET) regenerates the retention capacity at a rate that is variably influenced by climate, vegetation treatment, soil and residual moisture content. Experimental studies have been undertaken to monitor the drying cycle behaviour of 9 different extensive green roof configurations with 80 mm substrate depth. A climate-controlled chamber at the University of Sheffield replicated typical UK spring and summer diurnal cycles. The mass of each microcosm, initially at field capacity, was continuously recorded, with changes inferred to be moisture loss/gain (or ET/dew). The ranges of cumulative ET following a 28 day dry weather period (ADWP) were 0.6–1.0 mm/day in spring and 0.7–1.25 mm/day in summer. These ranges reflect the influence of configuration on ET. Cumulative ET was highest from substrates with the greatest storage capacity. Significant differences in ET existed between vegetated and non-vegetated configurations. Initially, seasonal mean ET was affected by climate. Losses were 2.0 mm/day in spring and 3.4 mm/day in summer. However, moisture availability constrained ET, which fell to 1.4 mm/day then 1.0 mm/day (with an ADWP of 7 and 14 days) in spring; compared to 1.0 mm/day and 0.5 mm/day in summer. A modelling approach, which factors Potential Evapotranspiration (PET) according to stored moisture content, predicts daily ET with very good accuracy (PBIAS = 2.0% [spring]; −0.8% [summer])
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