The host galaxies of luminous radio-quiet quasars

We present the results of a deep K-band imaging study which reveals the host galaxies around a sample of luminous radio-quiet quasars. The K-band images, obtained at UKIRT, are of sufficient quality to allow accurate modelling of the underlying host galaxy. Initially, the basic structure of the hosts is revealed using a modified Clean deconvolution routine optimised for this analysis. 2 of the 14 quasars are shown to have host galaxies with violently disturbed morphologies which cannot be modelled by smooth elliptical profiles. For the remainder of our sample, 2D models of the host and nuclear component are fitted to the images using the chi-squared statistic to determine goodness of fit. Host galaxies are detected around all of the quasars. The reliability of the modelling is extensively tested, and we find the host luminosity to be well constrained for 9 quasars. The derived average K-band absolute K-corrected host galaxy magnitude for these luminous radio-quiet quasars is =-25.15+/-0.04, slightly more luminous than an L* galaxy. The spread of derived host galaxy luminosities is small, although the spread of nuclear-to-host ratios is not. These host luminosities are shown to be comparable to those derived from samples of quasars of lower total luminosity and we conclude that there is no correlation between host and nuclear luminosity for these quasars. Nuclear-to-host ratios break the lower limit previously suggested from studies of lower nuclear luminosity quasars and Seyfert galaxies. Morphologies are less certain but, on the scales probed by these images, some hosts appear to be dominated by spheroids but others appear to have disk-dominated profiles.Comment: 16 pages, 8 figures, revised version to be published in MNRA

Neuroprotective Mechanism of Lycium barbarum Polysaccharides against Hippocampal-Dependent Spatial Memory Deficits in a Rat Model of Obstructive Sleep Apnea

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Wireless monitoring of liver hemodynamics in vivo

Liver transplants have their highest technical failure rate in the first two weeks following surgery. Currently, there are limited devices for continuous, real-time monitoring of the graft. In this work, a three wavelengths system is presented that combines near-infrared spectroscopy and photoplethysmography with a processing method that can uniquely measure and separate the venous and arterial oxygen contributions. This strategy allows for the quantification of tissue oxygen consumption used to study hepatic metabolic activity and to relate it to tissue stress. The sensor is battery operated and communicates wirelessly with a data acquisition computer which provides the possibility of implantation provided sufficient miniaturization. In two in vivo porcine studies, the sensor tracked perfusion changes in hepatic tissue during vascular occlusions with a root mean square error (RMSE) of 0.135 mL/min/g of tissue. We show the possibility of using the pulsatile wave to measure the arterial oxygen saturation similar to pulse oximetry. The signal is also used to extract the venous oxygen saturation from the direct current (DC) levels. Arterial and venous oxygen saturation changes were measured with an RMSE of 2.19% and 1.39% respectively when no vascular occlusions were induced. This error increased to 2.82% and 3.83% when vascular occlusions were induced during hypoxia. These errors are similar to the resolution of a commercial oximetry catheter used as a reference. This work is the first realization of a wireless optical sensor for continuous monitoring of hepatic hemodynamics. © 2014 Akl et al

Effect of Some Oligosaccharides on Functional Properties of Wheat Starch

Purpose: To investigate the effects of oligosaccharides on the functional properties of wheat starch.Methods: The blue value, retrogradation and pasting properties of wheat starch were determined. In addition, water activity (Aw), melting enthalpy and melting temperature of wheat starch paste were analyzed.Results: Fructo-oligosaccharide (FOS) and xylo-oligosaccharide (XOS) inhibited the retrogradation of wheat starch. The peak viscosity of wheat starch with oligosaccharides increased from 3238 ± 8 to 3822 ± 10 cP, with the highest peak obtained for sucrose. The setback of wheat starch decreased (from 1158 ± 5 to 799 ± 6 cP), with the lowest setback for FOS. Aw of control sample changed significantly (falling from 0.978 ± 0.025 to 0.397 ± 0.013) when the drying time was from 6 to 12 hours, while the Aw of the samples to which different oligosaccharides were added only showed slight decrease (from 0.98 ± 0.019 to 0.854 ± 0.022). During storage, the Aw of all starch pastes decreased, and the Aw and melting enthalpy of the samples containing FOS and XOS were significantly lower than that of the control after 6 days storage at 4 and 30 °C.Conclusion: A certain level of oligosaccharides can improve the functional properties of wheat starch paste and thus broaden its application prospects in food and pharmaceutical industries.Keywords: Melting enthalpy, Oligosaccharides, Pasting properties, Water activity, Wheat starc

Sorafenib dose escalation is not uniformly associated with blood pressure elevations in normotensive patients with advanced malignancies.

Hypertension after treatment with vascular endothelial growth factor (VEGF) receptor inhibitors is associated with superior treatment outcomes for advanced cancer patients. To determine whether increased sorafenib doses cause incremental increases in blood pressure (BP), we measured 12-h ambulatory BP in 41 normotensive advanced solid tumor patients in a randomized dose-escalation study. After 7 days' treatment (400 mg b.i.d.), mean diastolic BP (DBP) increased in both study groups. After dose escalation, group A (400 mg t.i.d.) had marginally significant further increase in 12-h mean DBP (P = 0.053), but group B (600 mg b.i.d.) did not achieve statistically significant increases (P = 0.25). Within groups, individuals varied in BP response to sorafenib dose escalation, but these differences did not correlate with changes in steady-state plasma sorafenib concentrations. These findings in normotensive patients suggest BP is a complex pharmacodynamic biomarker of VEGF inhibition. Patients have intrinsic differences in sensitivity to sorafenib's BP-elevating effects

Influence of southern hemispheric biomass burning on midtropospheric distributions of nonmethane hydrocarbons and selected halocarbons over the remote South Pacific

Aircraft measurements of nonmethane hydrocarbons (NMHCs) and halocarbons were made over the remote South Pacific Ocean during late August-early October 1996 for NASA's Global Tropospheric Experiment (GTE) Pacific Exploratory Mission-Tropics A (PEM-Tropics A). This paper discusses the large-scale spatial distributions of selected trace gases encountered during PEM-Tropics A. The PEM-Tropics A observations are compared to measurements made over the southwestern pacific in early November 1995 as part of Aerosol Characterization Experiment (ACE 1). Continental pollution in the form of layers containing elevated levels of O3 was observed during a majority of PEM-Tropics flights, as well as during several ACE 1 flights. The chemical composition of these air masses indicates that they were not fresh and were derived from nonurban combustion sources. The substantial impact of biomass burning on the vertical structure of the South Pacific troposphere is discussed. Copyright 1999 by the American Geophysical Union

A case study of transport of tropical marine boundary layer and lower tropospheric air masses to the northern midlatitude upper troposphere

Low-ozone (<20 ppbv) air masses were observed in the upper troposphere in northern midlatitudes over the eastern United States and the North Atlantic Ocean on several occasions in October 1997 during the NASA Subsonic Assessment, Ozone and Nitrogen Oxide Experiment (SONEX) mission. Three cases of low-ozone air masses were shown to have originated in the tropical Pacific marine boundary layer or lower troposphere and advected poleward along a warm conveyor belt during a synoptic-scale disturbance. The tropopause was elevated in the region with the low-ozone air mass. Stratospheric intrusions accompanied the disturbances. On the basis of storm track and stratospheric intrusion climatologies, such events appear to be more frequent from September through March than the rest of the year. Copyright 2000 by the American Geophysical Union