Organic constitution of the CO3 chondrites and implications for asteroidal processes

This paper reports the organic constitution of the CO3 chondrites identified by 4D TOFMS in order to decipher the composition, structure and alteration history of the CO3 parent asteroid

Aligning archive maps and extracting footprints for analysis of historic urban environments.

Archive cartography and archaeologist's sketches are invaluable resources when analysing a historic town or city. A virtual reconstruction of a city provides the user with the ability to navigate and explore an environment which no longer exists to obtain better insight into its design and purpose. However, the process of reconstructing the city from maps depicting features such as building footprints and roads can be labour intensive. In this paper we present techniques to aid in the semi-automatic extraction of building footprints from digital images of archive maps and sketches. Archive maps often exhibit problems in the form of inaccuracies and inconsistencies in scale which can lead to incorrect reconstructions. By aligning archive maps to accurate modern vector data one may reduce these problems. Furthermore, the efficiency of the footprint extraction methods may be improved by aligning either modern vector data or previously extracted footprints, since common elements can be identified between maps of differing time periods and only the difference between the two needs to be extracted. An evaluation of two alignment approaches is presented: using a linear affine transformation and a set of piecewise linear affine transformations

APOCALYPSE NO: Population Aging and the Future of Health Care Systems

Illness increases with age. All else equal, an older population has greater needs for health care. This logic has led to dire predictions of skyrocketing costs-- "apocalyptic demography". Yet numerous studies have shown that aging effects are relatively small, and all else is not equal. Cost projections rest on specific assumptions about trends in age- specific morbidity and health care use that are far from self-evident. Sharply contrasting assumptions, for example, are made by Fries, who foresees a "compression of morbidity" and falling needs. Long term trends in health care use in British Columbia show minimal effects of population aging, but major effects, up and down, from changes in age- specific use patterns. Why then is the demographic apocalypse story so persistent, despite numerous contrary studies? It serves identifiable economic interests.aging, health care utilization, demography, health care financing

Nevanlinna theory for the q-difference operator and meromorphic solutions of q-difference equations

Nevanlinna theory for the q-difference operator and meromorphic solutions of q-difference equation

Prediction of multiple infections after severe burn trauma: a prospective cohort study.

OBJECTIVE: To develop predictive models for early triage of burn patients based on hypersusceptibility to repeated infections. BACKGROUND: Infection remains a major cause of mortality and morbidity after severe trauma, demanding new strategies to combat infections. Models for infection prediction are lacking. METHODS: Secondary analysis of 459 burn patients (≥16 years old) with 20% or more total body surface area burns recruited from 6 US burn centers. We compared blood transcriptomes with a 180-hour cutoff on the injury-to-transcriptome interval of 47 patients (≤1 infection episode) to those of 66 hypersusceptible patients [multiple (≥2) infection episodes (MIE)]. We used LASSO regression to select biomarkers and multivariate logistic regression to built models, accuracy of which were assessed by area under receiver operating characteristic curve (AUROC) and cross-validation. RESULTS: Three predictive models were developed using covariates of (1) clinical characteristics; (2) expression profiles of 14 genomic probes; (3) combining (1) and (2). The genomic and clinical models were highly predictive of MIE status [AUROCGenomic = 0.946 (95% CI: 0.906-0.986); AUROCClinical = 0.864 (CI: 0.794-0.933); AUROCGenomic/AUROCClinical P = 0.044]. Combined model has an increased AUROCCombined of 0.967 (CI: 0.940-0.993) compared with the individual models (AUROCCombined/AUROCClinical P = 0.0069). Hypersusceptible patients show early alterations in immune-related signaling pathways, epigenetic modulation, and chromatin remodeling. CONCLUSIONS: Early triage of burn patients more susceptible to infections can be made using clinical characteristics and/or genomic signatures. Genomic signature suggests new insights into the pathophysiology of hypersusceptibility to infection may lead to novel potential therapeutic or prophylactic targets

On the role of inlet flow instabilities on horizontal initially stratified liquid-liquid flow development

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.For a given pair of fluid phases, liquid-liquid flows are generally described in terms of regimes (e.g. stratified, wavy or dispersed), which are a function of the Reynolds numbers of the individual phases, the geometry of the flow, as well as the inlet conditions and the distance from the inlet. Typically, injecting the heavier phase at the bottom of the channel and the lighter phase at the top is the common inlet configuration when establishing a liquid-liquid flow for study in a laboratory environment. This configuration corresponds to that expected in a naturally separated flow orientation, on the assumption that at long lengths the density difference between the two phases will lead to this arrangement of the two phases. In this study, a series of experiments were designed to investigate the influence of injecting the heavier phase at the top of the pipe rather than at the bottom. This modification introduces the possibility of phase breakup near the inlet by an additional instability mechanism (due to the density difference between the two liquids), which would not appear had the phases been introduced in the conventional inlet flow arrangement. We perform detailed flow measurements and observe that this flow arrangement gives rise to altered flow structures downstream. Moreover, our results suggest that the effects of this instability near the inlet may persist along the pipe and influence the observed flow behaviour even at long lengths.cf201

Experimental investigations of two-phase liquid-liquid horizontal flows through orifice plates

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.This paper is concerned with two-phase liquid-liquid flows through orifice plates in horizontal pipes, and in particular with a phenomenon known as “phase inversion” that can occur in dispersed flow. Experimental investigations were carried out in which two-phase flows comprising oil and water were pumped via an inlet section into a horizontal pipe of diameter 25.4 mm and length 7 m. In one series of experiments the light phase (oil) was introduced into the inlet section above the heavier one (water), in a “stable” inlet configuration. This was followed by a set of experiments in which the water was introduced above the oil, in an “unstable” inlet configuration. Furthermore, tests were performed with and without the insertion of a static mixer just downstream of the inlet. The orifice plate was placed in two alternate positions with respect to the inlet: one near (1.30 m) the inlet, and one far (5.20 m) downstream, i.e., in both developing and fully developed flows. The pressure drop across the orifice plate was measured with a differential pressure transducer in a series of independent experimental runs in which the two liquid flow-rates were varied independently in order to span a range of superficial mixture velocities and inlet phase fractions (water-cuts). From the data generated in the present experimental campaign, the pressure drop measured across the orifice plate showed a gradual increase as the mixture velocities were increased, as expected. However, for a given mixture velocity, a decrease in the pressure drop across the orifice plate was observed as the water-cut was varied. This decrease was observed at water-cut values that were close to those for which phase inversion was expected in our flows (~0.2-0.3). It is inferred that the phase inversion point may be associated with this decrease in pressure drop. This interesting finding is contrary to the increase in pressure drop demonstrated in previous studies involving two-phase pipe flow and has important implications for the design of pipeline systems that incorporate orifice plates for flow measurement. In addition, the inlet orientation appeared to have little effect on the phase inversion point.dc201

Gravitational quasinormal modes of AdS black branes in d spacetime dimensions

The AdS/CFT duality has established a mapping between quantities in the bulk AdS black-hole physics and observables in a boundary finite-temperature field theory. Such a relationship appears to be valid for an arbitrary number of spacetime dimensions, extrapolating the original formulations of Maldacena's correspondence. In the same sense properties like the hydrodynamic behavior of AdS black-hole fluctuations have been proved to be universal. We investigate in this work the complete quasinormal spectra of gravitational perturbations of $d$-dimensional plane-symmetric AdS black holes (black branes). Holographically the frequencies of the quasinormal modes correspond to the poles of two-point correlation functions of the field-theory stress-energy tensor. The important issue of the correct boundary condition to be imposed on the gauge-invariant perturbation fields at the AdS boundary is studied and elucidated in a fully $d$-dimensional context. We obtain the dispersion relations of the first few modes in the low-, intermediate- and high-wavenumber regimes. The sound-wave (shear-mode) behavior of scalar (vector)-type low-frequency quasinormal mode is analytically and numerically confirmed. These results are found employing both a power series method and a direct numerical integration scheme.Comment: added references, typos corrected, minor changes, final version for JHE

Superconducting Transition Temperature in Heterogeneous Ferromagnet-Superconductor Systems

We study the shift of the the superconducting transition temperature $T_c$ in ferromagnetic-superconducting bi-layers and in a superconducting film supplied a square array of ferromagnetic dots. We find that the transition temperature in these two cases change presumably in opposite direction and that its change is not too small. We extend these results to multilayer structures. We predict that rather small external magnetic field $\sim 10$ Oe can change the transition temperature of the bilayer by 10% .Comment: 9 pages, 2 figure

A study on the sensitivities of simulated aerosol optical properties to composition and size distribution using airborne measurements

We present a flexible framework to calculate the optical properties of atmospheric aerosols at a given relative humidity based on their composition and size distribution. The similarity of this framework to climate model parameterisations allows rapid and extensive sensitivity tests of the impact of uncertainties in data or of new measurements on climate relevant aerosol properties. The data collected by the FAAM BAe-146 aircraft during the EUCAARI-LONGREX and VOCALS-REx campaigns have been used in a closure study to analyse the agreement between calculated and measured aerosol optical properties for two very different aerosol types. The agreement achieved for the EUCAARI-LONGREX flights is within the measurement uncertainties for both scattering and absorption. However, there is poor agreement between the calculated and the measured scattering for the VOCALS-REx flights. The high concentration of sulphate, which is a scattering aerosol with no absorption in the visible spectrum, made the absorption measurements during VOCALS-REx unreliable, and thus no closure study was possible for the absorption. The calculated hygroscopic scattering growth factor overestimates the measured values during EUCAARI-LONGREX and VOCALS-REx by ∼30% and ∼20%, respectively. We have also tested the sensitivity of the calculated aerosol optical properties to the uncertainties in the refractive indices, the hygroscopic growth factors and the aerosol size distribution. The largest source of uncertainty in the calculated scattering is the aerosol size distribution (∼35%), followed by the assumed hygroscopic growth factor for organic aerosol (∼15%), while the predominant source of uncertainty in the calculated absorption is the refractive index of organic aerosol (28–60%), although we would expect the refractive index of black carbon to be important for aerosol with a higher black carbon fraction