909 research outputs found
A cross-sectional study on nutrient intake and -status in inflammatory bowel disease patients.
To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files.
This article is open access.Inflammatory bowel disease (IBD) can be associated with nutritional problems. The aim of this study was to investigate diet and nutritional status of IBD patients.A total of 78 participants (35 men and 43 women aged 18-74 years) were included in this cross-sectional study. The majority (80 %) of the participant received infliximab treatment. Participants filled out disease related questionnaires and 31 participants also a 3-day food record. Body composition was measured and blood samples analysed in order to estimate nutritional status.The majority (87 %) claimed that diet affects digestive tract symptoms and 72 % had changed diet accordingly. The most common foods restricted were dairy products (60 %), processed meat (55 %), soft drinks (46 %), alcohol (45 %) and fast food (44 %). Body mass index was mostly in the overweight range but 46 % of the participants had been diagnosed with some nutritional deficiency since IBD diagnosis (most common was iron deficiency: 39 %). Patients who restricted meat products had lower ferritin values (48 ± 39 vs. 95 ± 74 μg/L, P = 0.011). Intake of vitamin D and calcium were not adequate (65 % below recommeded intake for both) and 60 % had poor vitamin D status.IBD patients often change their dietary intake in order to affect digestive tract symptoms. Many patients have a history of nutrient deficiency. Restriction of dairy and meat consumption is common and is negatively associated with intake or status of micronutrients like calcium and iron. Dietary advice by a dietitian and use of potentially helpful dietary supplements is indicated.Science funds of the Landspitali- The National University Hospital of Icelan
Observations of large flow shears around small-scale auroral beads observed at substorm onset
第2回極域科学シンポジウム/第35回極域宙空圏シンポジウム 11月16日(水) 統計数理研究所 3階リフレッシュフロ
Electron-Positron Pairs in Hot Accretion Flows and Thin Disk Coronae
We investigate equilibrium accretion flows dominated by pairs. We
consider one- and two-temperature accretion disk coronae above a thin disk, as
well as hot optically thin two-temperature accretion flows without an
underlying thin disk; we model the latter in the framework of
advection-dominated accretion flows (ADAFs). In all three cases we include
equipartition magnetic fields. We confirm the previous result that the
equilibrium density of pairs in two-temperature ADAFs is negligible; and show
that the inclusion of magnetic fields and the corresponding synchrotron cooling
reduces the pair density even further. Similarly, we find that pairs are
unimportant in two-temperature coronae. Even when the corona has significantly
enhanced heating by direct transfer of viscous dissipation in the thin disk to
the corona, the inefficient Coulomb coupling between protons and electrons acts
as a bottleneck and prevents the high compactness required for pair-dominated
solutions. Only in the case of a one-temperature corona model do we find
pair-dominated thermal equilibria. These pair-dominated solutions occur over a
limited range of optical depth and temperature.Comment: 38 pages, including 10 figures, LaTeX; to appear in Ap
Novel Image Analysis Approach Quantifies Morphological Characteristics of 3D Breast Culture Acini with Varying Metastatic Potentials
Prognosis of breast cancer is primarily predicted by the histological grading of the tumor, where pathologists manually evaluate microscopic characteristics of the tissue. This labor intensive process suffers from intra- and inter-observer variations; thus, computer-aided systems that accomplish this assessment automatically are in high demand. We address this by developing an image analysis framework for the automated grading of breast cancer in in vitro three-dimensional breast epithelial acini through the characterization of acinar structure morphology. A set of statistically significant features for the characterization of acini morphology are exploited for the automated grading of six (MCF10 series) cell line cultures mimicking three grades of breast cancer along the metastatic cascade. In addition to capturing both expected and visually differentiable changes, we quantify subtle differences that pose a challenge to assess through microscopic inspection. Our method achieves 89.0% accuracy in grading the acinar structures as nonmalignant, noninvasive carcinoma, and invasive carcinoma grades. We further demonstrate that the proposed methodology can be successfully applied for the grading of in vivo tissue samples albeit with additional constraints. These results indicate that the proposed features can be used to describe the relationship between the acini morphology and cellular function along the metastatic cascade
Increased prevalence of sleep disturbances and daytime sleepiness in subjects with bronchial asthma: a population study of young adults in three European countries
To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldThe aim of this study was to investigate whether asthma is associated with decreased quality of sleep and increased daytime sleepiness. The study involved a random population of 2,202 subjects supplemented by 459 subjects with suspected asthma, aged 20-45 yrs. The subjects were from Reykjavik (Iceland), Uppsala and Göteborg (Sweden) and Antwerp (Belgium), and participated in the European Community Respiratory Health Survey. The investigation included a structured interview, methacholine challenge, skinprick tests and a questionnaire on sleep disturbances. Participants in Iceland and Sweden also estimated their sleep times and made peak expiratory flow (PEF) recordings during a period of 1 week. Asthma was defined as self-reported physician-diagnosed asthma with current asthma-related symptoms (n = 267). Difficulties inducing sleep (DIS) and early morning awakenings (EMA) were about twice as common, and daytime sleepiness 50% more common, in asthmatics compared with subjects without asthma. After adjusting for possible confounders, a positive association was found between asthma and: DIS (odds ratio (OR) = 1.8); EMA (OR = 2.0); daytime sleepiness (OR = 1.6); snoring (OR = 1.7); and self reported apnoeas (OR = 3.7). Allergic rhinitis, which was reported by 71% of subjects with asthma, was independently related to DIS (OR = 2.0) and daytime sleepiness (OR = 1.3). A significant correlation was found between the number of asthma-related symptoms and sleep disturbances (p < 0.001). Asthma is associated with decreased subjective quality of sleep and increased daytime sleepiness. Concurrent allergic rhinitis may be an important underlying cause of sleep impairment in asthmatic patients
The D^{2k} R^4 Invariants of N=8 Supergravity
The existence of a linearized SUSY invariant for N=8 supergravity whose
gravitational components are usually called R^4 was established long ago by
on-shell superspace arguments. Superspace and string theory methods have also
established analogous higher dimensional D^{2k} R^4 invariants. However, very
little is known about the SUSY completions of these operators which involve
other fields of the theory. In this paper we find the detailed component
expansion of the linearized R^4 invariant starting from the corresponding
superamplitude which generates all component matrix elements of the operator.
It is then quite straightforward to extend results to the entire set of D^{2k}
R^4 operators.Comment: 17 page
Gamma-Ray Burst Spectral Correlations: Photospheric and Injection Effects
We present a physical framework that can account for most of the observed
spectral properties of the prompt gamma-ray burst emission. This includes the
variety of spectral shapes, shape evolutions, and spectral correlations between
flux and spectral peak, within bursts described by Borgonovo & Ryde, and among
bursts described by Amati/Ghirlanda. In our proposed model the spectral peak is
given by the photospheric emission from a relativistic outflow for which the
horizon length is much smaller than the radial width. The observed duration of
the thermal flash will be given by the radial light-crossing time. This then
gives that the typical emission site is at ~10e11 cm from the center, with a
Lorentz factor of ~300. This emission is accompanied by non-thermal emission
from dissipation locations outside the photosphere. The relative strength of
these two components depend on injection effects at the central engine leading
to varying relative location of the saturation and photospheric radii. The
total emission can then reproduce the observed variety. The spectral
correlations are found by assuming that the amount of energy dissipated depends
non-linearly on the averaged particle density. Beside the spectral correlations
this also gives a description of how the relative strength of the thermal
component varies with temperature within a burst.Comment: ApJ accepted, acknowledgement adde
Gravity and elevation changes at Askja, Iceland
Ground tilt measurements demonstrate that Askja is in a state of unrest, and that in the period 1988 - 1991 a maximum 48 +/- 3 µrad tilt occurred down towards the centre of the caldera. This is consistent with 126 mm of deflation at the centre of the caldera with a 2.5 - 3.0 km depth to the source of deformation. The volume of the subsidence bowl is 6.2 x 106 m3. When combined with high precision microgravity measurements, the overall change in sub-surface mass may be quantified. After correction for the observed elevation change using the free air gradient of gravity measured for each station, the total change in mass is estimated to be less than 109 kg. A small residual ground inflation and net gravity increase in the eastern part of the caldera may be caused by dyke intrusion in this region. The minimum dimensions of such an intrusion or complex of intrusions are 1m width, up to 100m deep and up to several hundred metres thick
The jet and circumburst stellar wind of GRB 980519
We present extensive multi-colour (UBVR_CI_C) photometry of the optical
afterglow of GRB 980519. Upon discovery, 8.3 hours after the burst, the source
was decaying as a power law, (t-t_GRB)^alpha, with a rapid decay rate alpha_1 =
- 1.73+-0.04. About 13 hours after the burst a steepening of the light-curve to
alpha_2 = -2.22+-0.04 was observed. Within the framework of current afterglow
models, we argue that the rapid initial decline, the `break' in the light
curve, and the spectral properties of the afterglow are best interpreted as
being due to a collimated ultra-relativistic jet of fixed opening angle
expanding into an inhomogeneous medium. In this scenario, we find that the
circumburst medium has a density structure that goes as r^(-2.05+-0.22). This
is characteristic of a preexisting wind expelled from a massive star. A
possible physical scenario is that the progenitor star collapsed to form a
black hole (i.e., a `collapsar'), producing the observed burst and afterglow.
However, the supernova signature expected in the light curve in such a scenario
is not detected. This either implies that the redshift of GRB980519 is greater
than 1.5 or that supernovae accompanying GRBs are not standard candles.Comment: 11 pages, including 2 tables and 3 figures. Accepted for publication
in ApJ, part
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