1,445 research outputs found
Factors that affect serum levels of ferritin in Australian adults and implications for Follow-up
Background & Aims
Serum levels of ferritin are commonly measured to assess iron stores but are affected by factors such as obesity and chronic disease. Published reference ranges have not changed in decades, and the number of patients whose levels exceed the upper limits has been increasing. As a result, more patients are evaluated for iron overload.
Methods
We compared serum levels of ferritin in 1188 Australian adults who participated in the 2005 Busselton Population Survey with levels from the 1995 survey. Parametric regression was used to assess the effects of body weight and biochemical parameters on serum level of ferritin to derive contemporary population-appropriate reference ranges.
Results
In 2005, age-adjusted levels of ferritin were 21% higher in men (P < .0001) and 10% higher in women (P = .01) than in 1995; 31% of men exceeded levels of 300 ÎŒg/L, compared with 23% in 1995. Body mass index (BMI) â„25 kg/m2 was associated with higher levels of ferritin in men â„35 years old and in postmenopausal women (P †.002). Serum level of Îł-glutamyltransferase (GGT) correlated with serum level of ferritin (P < .0001). In men, the estimated 95th percentiles ranged from 353 to 495 ÎŒg/L (<35 years), from 350 to 511 ÎŒg/L (â„35 years, BMI <25 kg/m2), and from 413 to 696 ÎŒg/L (â„35 years, BMI â„25 kg/m2) when GGT levels were 10â75 IU/L. In women, the 95th percentiles ranged from 106 to 235 ÎŒg/L (premenopausal), from 222 to 323 ÎŒg/L (postmenopausal, BMI <25 kg/m2), and from 249 to 422 ÎŒg/L (postmenopausal, BMI â„25 kg/m2) when GGT levels were 8â45 IU/L.
Conclusion
Serum levels of ferritin increased significantly between 1995 and 2005. Reference ranges that accommodate demographic and biomedical variations will assist clinicians in identifying individuals who require further evaluation for iron overload
Absence of a dose-rate effect in the transformation of C3H 10T1/2 cells by α-particles
The findings of Hill et al. (1984) on the greatly enhanced transformation frequencies at very low dose rates of fission neutrons induced us to perform an analogous study with -particles at comparable dose rates. Transformation frequencies were determined with γ-rays at high dose rate (0·5 Gy/min), and with -particles at high (0·2 Gy/min) and at low dose rates (0·83-2·5 mGy/min) in the C3H 10T1/2 cell system.
α-particles were substantially more effective than γ-rays, both for cell inactivation and for neoplastic transformation at high and low dose rates. The relative biological effectiveness (RBE) for cell inactivation and for neoplastic transformation was of similar magnitude, and ranged from about 3 at an -particle dose of 2 Gy to values of the order of 10 at 0·25 Gy. In contrast to the experiments of Hill et al. (1984) with fission neutrons, no increased transformation frequencies were observed when the -particle dose was protracted over several hours
Nonsmooth analysis of doubly nonlinear evolution equations
In this paper we analyze a broad class of abstract doubly nonlinear evolution
equations in Banach spaces, driven by nonsmooth and nonconvex energies. We
provide some general sufficient conditions, on the dissipation potential and
the energy functional,for existence of solutions to the related Cauchy problem.
We prove our main existence result by passing to the limit in a
time-discretization scheme with variational techniques. Finally, we discuss an
application to a material model in finite-strain elasticity.Comment: 45 page
Putting theory oriented evaluation into practice
Evaluations of gaming simulations and business games as teaching devices are typically end-state driven. This emphasis fails to detect how the simulation being evaluated does or does not bring about its desired consequences. This paper advances the use of a logic model approach which possesses a holistic perspective that aims at including all elements associated with the situation created by a game. The use of the logic model approach is illustrated as applied to Simgame, a board game created for secondary school level business education in six European Union countries
SU(2) Calorons and Magnetic Monopoles
We investigate the self-dual Yang-Mills gauge configurations on when the gauge symmetry SU(2) is broken to U(1) by the Wilson loop. We
construct the explicit field configuration for a single instanton by the Nahm
method and show that an instanton is composed of two self-dual monopoles of
opposite magnetic charge. We normalize the moduli space metric of an instanton
and study various limits of the field configuration and its moduli space
metric.Comment: 17 pages, RevTex, 1 Figur
Dating the funerary use of caves in Liguria (northwestern Italy) from the Neolithic to historic times:Results from a large-scale AMS campaign on human skeletal series
The multidisciplinary research team of this new project aimed at the chronological, anthropological and funerary behavior characterization of the skeletal remains unearthed from various caves in western Liguria (northwestern Italy) between the mid-1800s and the 1990s. Most of the burials and scattered bone assemblages were excavated prior to the development of modern stratigraphic methods, or come from disturbed contexts, often resulting in a vague chrono-cultural attribution. We present here the results of a systematic dating project that produced 130 new AMS dates on human bone samples (documented burials or individuals from scattered remains) from sixteen Ligurian caves, including most of the skeletal series from renowned sites such as Arene Candide Cave and Grotta Pollera. Results highlighted the funerary use of these caves from the last quarter of the sixth millennium BCE to the Common Era, with the majority of results clustering in the first half of the fifth millennium BCE. These dates allow for an initial assessment of patterns in Neolithic mortuary use of Ligurian caves, and aided in particular the characterization of funerary practices during the Square Mouthed Pottery culture
Anti-tumour necrosis factor agent and liver injury : literature review, recommendations for management
Abnormalities in liver function tests, including transient and self-limiting hypertransaminasemia, cholestatic disease and hepatitis, can develop during treatment with anti-tumour-necrosis-factor (TNF) therapy. The optimal management of liver injury related to anti-TNF therapy is still a matter of debate. Although some authors recommend discontinuing treatment in case of both a rise of alanine aminotransferase more than 5 times the upper limit of normal, or the occurrence of jaundice, there are no standard guidelines for the management of anti-TNF-related liver injury. Bibliographical searches were performed in PubMed, using the following key words: inflammatory bowel disease (IBD); TNF inhibitors; hypertransaminasemia; drug-related liver injury; infliximab. According to published data, elevation of transaminases in patients with IBD treated with anti-TNF is a common finding, but resolution appears to be the usual outcome. Anti-TNF agents seem to be safe with a low risk of causing severe drug-related liver injury. According to our centre experience, we found that hypertransaminasemia was a common, mainly self-limiting finding in our IBD cohort and was not correlated to infliximab treatment on both univariate and multivariate analyses. An algorithm for the management of liver impairment occurring during anti-TNF treatment is also proposed and this highlights the need of a multidisciplinary approach and suggests liver biopsy as a key-point in the management decision in case of severe rise of transaminases. However, hepatic injury is generally self-limiting and drug withdrawal seems to be an exception
Forward and midrapidity like-particle ratios from p+p collisions at sqrt(s)=200 GeV
We present a measurement of pi-\pi+, K-/K+ and pbar/p from p+p collisions at
sqrt(s) = 20 0GeV over the rapidity range 0<y<3.4. For pT < 2.0 GeV/c we see no
significant transverse momentum dependence of the ratios. All three ratios are
independent of rapidity for y ~< 1.5 and then steadily decline from y ~ 1.5 to
y ~ 3. The pi-\pi+ ratio is below unity for y > 2.0. The pbar/p ratio is very
similar for p+p and 20% central Au+Au collisions at all rapidities. In the
fragmentation region the three ratios seem to be independent of beam energy
when viewed from the rest frame of one of the protons. Theoretical models based
on quark-diquark breaking mechanisms overestimate the pbar/p ratio up to y ~<
3. Including additional mechanisms for baryon number transport such as baryon
junctions leads to a better description of the data.Comment: 15 pages, 4 figures, uses elsart.sty. Changes to references and
discussion based on referee comments, resubmitted to Phys. Lett.
Measurement of Through-Going Particle Momentum By Means Of Multiple Scattering With The ICARUS T600 TPC
The ICARUS collaboration has demonstrated, following the operation of a 600
ton (T600) detector at shallow depth, that the technique based on liquid Argon
TPCs is now mature. The study of rare events, not contemplated in the Standard
Model, can greatly benefit from the use of this kind of detectors. In
particular, a deeper understanding of atmospheric neutrino properties will be
obtained thanks to the unprecedented quality of the data ICARUS provides.
However if we concentrate on the T600 performance, most of the
charged current sample will be partially contained, due to the reduced
dimensions of the detector. In this article, we address the problem of how well
we can determine the kinematics of events having partially contained tracks.
The analysis of a large sample of atmospheric muons collected during the T600
test run demonstrate that, in case the recorded track is at least one meter
long, the muon momentum can be reconstructed by an algorithm that measures the
Multiple Coulomb Scattering along the particle's path. Moreover, we show that
momentum resolution can be improved by a factor two using an algorithm based on
the Kalman Filtering technique
Au+Au Reactions at the AGS: Experiments E866 and E917
Particle production and correlation functions from Au+Au reactions have been
measured as a function of both beam energy (2-10.7AGeV) and impact parameter.
These results are used to probe the dynamics of heavy-ion reactions, confront
hadronic models over a wide range of conditions and to search for the onset of
new phenomena.Comment: 12 pages, 14 figures, Talk presented at Quark Matter '9
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