105,622 research outputs found
Estimating T-cell repertoire diversity: limitations of classical estimators and a new approach
Erythema nodosum as a result of estrogen patch therapy for prostate cancer: a case report.
© 2015 Coyle et al.Introduction: Erythema nodosum is often associated with a distressing symptomatology, including painful subcutaneous nodules, polyarthropathy, and significant fatigue. Whilst it is a well-documented side-effect of estrogen therapy in females, we describe what we believe to be the first report in the literature of erythema nodosum as a result of estrogen therapy in a male. Case presentation: A 64-year-old Afro-Caribbean man with locally advanced carcinoma of the prostate agreed to participate in a randomized controlled trial comparing estrogen patches with luteinizing hormone-releasing hormone analogs to achieve androgen deprivation, and was allocated to the group receiving estrogen patches. One month later he presented with tender lesions on his shins and painful swelling of his ankles, wrists, and left shoulder. This was followed by progressive severe fatigue that required hospital admission, where he was diagnosed with erythema nodosum by a rheumatologist. Two months after discontinuing the estrogen patches the erythema nodosum, and associated symptoms, had fully resolved, and to date he remains well with no further recurrence. Conclusion: Trial results may establish transdermal estrogen as an alternative to luteinizing hormone-releasing hormone analogs in the management of prostate cancer, and has already been established as a therapy for male to female transsexuals. It is essential to record the toxicity profile of transdermal estrogen in men to ensure accurate safety information. This case report highlights a previously undocumented toxicity of estrogen therapy in men, of which oncologists, urologists, and endocrinologists need to be aware. Rheumatologists and dermatologists should add estrogen therapy to their differential diagnosis of men presenting with erythema nodosum
Simple models for two-dimensional tunable colloidal crystals in rotating ac electric fields
We compare the behavior of a new two-dimensional aqueous colloidal model
system with a simple numerical treatment. To the first order the attractive
interaction between the colloids induced by an in-plane rotating ac electric
field is dipolar, while the charge stabilization leads to a shorter ranged,
Yukawa-like repulsion. In the crystal-like 'rafts' formed at sufficient field
strengths, we find quantitative agreement between experiment and Monte Carlo
simulation, except in the case of strongly interacting systems, where the well
depth of the effective potential exceeds 250 times the thermal energy. The
'lattice constant' of the crystal-like raft is located approximately at the
minimum of the effective potential, resulting from the sum of the Yukawa and
dipolar interactions.The experimental system has display applications, owing to
the possibility of tuning the lattice spacing with the external electric field.
Limitations in the applied field strength and relative range of the
electrostatic interactions of the particles result in a reduction in tunable
lattice spacing for small and large particles, respectively. The optimal
particle size for maximizing the lattice spacing tunability was found to be
around 1000 nm.Comment: 25 pages 13 figure
The Stratigraphic Record of Pre-breakup Geodynamics: Evidence from the Barrow Delta, offshore Northwest Australia
The structural and stratigraphic evolution of rift basins and passive margins has been widely studied, with many analyses demonstrating that delta systems can provide important records of post-rift geodynamic processes. However, the apparent lack of ancient syn-breakup delta systems and the paucity of seismic imaging across continent-ocean boundaries means the transition from continental rifting to oceanic spreading remains poorly understood. The Early Cretaceous Barrow Group of the North Carnarvon Basin, offshore NW Australia was a major deltaic system that formed during the latter stages of continental rifting, and represents a rich sedimentary archive, documenting uplift, subsidence and erosion of the margin. We use a regional database of 2D and 3D seismic and well data to constrain the internal architecture of the Barrow Group. Our results highlight three major depocentres: the Exmouth and Barrow sub-basins, and southern Exmouth Plateau. Over-compaction of pre-Cretaceous sedimentary rocks in the South Carnarvon Basin, and pervasive reworking of Permian and Triassic palynomorphs in the offshore Barrow Group, suggests that the onshore South Carnarvon Basin originally contained a thicker sedimentary succession, which was uplifted and eroded prior to breakup. Backstripping of sedimentary successions encountered in wells in the Exmouth Plateau depocentre indicate anomalously rapid tectonic subsidence (≤0.24 mm yr-1) accommodated Barrow Group deposition, despite evidence for minimal, contemporaneous upper crustal extension. Our results suggest that classic models of uniform extension cannot account for the observations of uplift and subsidence in the North Carnarvon Basin, and may indicate a period of depth-dependent extension or dynamic topography preceding breakup
3D beam-column finite element under non-uniform shear stress distribution due to shear and torsion
The paper discusses the application of a 2-node, three-dimensional (3D) beam-column finite element with an enhanced fiber cross-section model to the inelastic response analysis of concrete members. The element accounts for the local distribution of strains and stresses under the coupling of axial, flexural, shear, and torsional effects with an enriched kinematic description that accounts for the out-of-plane deformations of the cross-section. To this end the warping displacements are interpolated with the addition of a variable number of local degrees of freedom. The material response is governed by a 3D nonlinear stress-strain relation with damage that describes the degrading mechanisms of typical engineering materials under the coupling of normal and shear stresses. The element formulation is validated by comparing the numerical results with measured data from the response of two prismatic concrete beams under torsional loading and with standard beam formulations
Spatial-temporal rainfall simulation using generalized linear models
We consider the problem of simulating sequences of daily rainfall at a network of sites in such a way as to reproduce a variety of properties realistically over a range of spatial scales. The properties of interest will vary between applications but typically will include some measures of "extreme'' rainfall in addition to means, variances, proportions of wet days, and autocorrelation structure. Our approach is to fit a generalized linear model (GLM) to rain gauge data and, with appropriate incorporation of intersite dependence structure, to use the GLM to generate simulated sequences. We illustrate the methodology using a data set from southern England and show that the GLM is able to reproduce many properties at spatial scales ranging from a single site to 2000 km 2 ( the limit of the available data)
Software for cut-generating functions in the Gomory--Johnson model and beyond
We present software for investigations with cut generating functions in the
Gomory-Johnson model and extensions, implemented in the computer algebra system
SageMath.Comment: 8 pages, 3 figures; to appear in Proc. International Congress on
Mathematical Software 201
Improving academic learning from computer-based narrative games
Although many strong claims are made for the power of computer games to promote academic learning, the narrative content of a game may reduce the learner's tendency to reflect on its academic content. The present study examines adding a low-cost instructional feature intended to promote appropriate cognitive processing of the academic content during play. College students played a computer adventure game in which they guided a character through a bunker in search of lost artwork, building electromechanical devices to open stuck doors along the way. In Experiment 1, students who filled out worksheets about wet-cell batteries before and during the game outperformed students who played the game without worksheets on a written explanation of how wet-cell batteries work (d = 0.92), multiple-choice comprehension questions about wet-cell batteries (d = 0.67), and open-ended transfer problems about wet-cell batteries (d = 0.74). In Experiment 2, participants who completed only the in-game worksheet outperformed the control group on a written explanation of wet-cell batteries (d = 0.59) and transfer problems (d = 0.67), whereas participants who completed only the pre-game worksheet did not outperform the control group on any measure. These findings point to the learning benefits of adding instructional features suggested by cognitive theories of learning
Binary Decision Diagrams: from Tree Compaction to Sampling
Any Boolean function corresponds with a complete full binary decision tree.
This tree can in turn be represented in a maximally compact form as a direct
acyclic graph where common subtrees are factored and shared, keeping only one
copy of each unique subtree. This yields the celebrated and widely used
structure called reduced ordered binary decision diagram (ROBDD). We propose to
revisit the classical compaction process to give a new way of enumerating
ROBDDs of a given size without considering fully expanded trees and the
compaction step. Our method also provides an unranking procedure for the set of
ROBDDs. As a by-product we get a random uniform and exhaustive sampler for
ROBDDs for a given number of variables and size
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