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Functional diversity of LIM proteins : amino-terminal activation domains in the oncogenic proteins RBTN1 and RBTN2

The RBTN1 and RBTN2 genes are activated by distinct translocations involving chromosome 11 in some T cell acute leukaemias. The RBTN proteins belong to the LIM family which comprises proteins with one, two or three cysteine-rich LIM domains, sometimes together with homeodomains or protein kinase domains. The RBTN1 and RBTN2 proteins comprise only tandem LIM domains. We report that RBTN1 and RBTN2

Signal-to-noise criterion for free-propagation imaging techniques at free-electron lasers and synchrotrons

We propose a signal-to-noise criterion which predicts whether a feature of a given size and scattering strength, placed inside a larger object, can be retrieved with two common X-ray imaging techniques: coherent diffraction imaging and projection microscopy. This criterion, based on how efficiently these techniques detect the scattered photons and validated through simulations, shows in general th

Dynamic ventilation 3He MRI for the quantification of disease in the rat lung

Pulmonary diseases are known to be largely inhomogeneous. To evaluate such inhomogeneities, we are testing an image-based method to measure gas flow in the lung regionally. Dynamic, spin-density-weighted hyperpolarized (3)He MR images performed during slow inhalation of this gas were analyzed to quantify regional inflation rate. This parameter was measured in regions of interest (ROIs) that were d

Echo-planar MR imaging of dissolved hyperpolarized 129Xe : Potential for MR angiography

PURPOSE: The feasibility of hyperpolarized 129Xe for fast MR angiography (MRA) was evaluated using the echo-planar imaging (EPI) technique.MATERIAL AND METHODS: Hyperpolarized Xe gas was dissolved in ethanol, a carrier agent with high solubility for Xe (Ostwald solubility coefficient 2.5) and long relaxation times. The dissolved Xe was injected as a bolus into a flow phantom where the mean flow ve

Gd‐DTPA2–‐enhanced MRI of femoral knee cartilage: A dose‐response study in healthy volunteers

The negatively charged contrast agent Gd-DTPA2- distributes inversely to the cartilage fixed charged density. This enables structural cartilage examinations by contrast-enhanced MRI. In line with the development of a clinically applicable protocol for such examinations, this study describes the temporal pattern of Gd-DTPA2- distribution in femoral knee cartilage at three different doses in healthy

Political comedy engagement : Genre work, political identity and cultural citizenship

Politisk komedi är en hybridgenre där politiska nyheter och analyser blandas med komedi och underhållning. Allt eftersom politisk komedi ökar i popularitet – i de flesta medieformer och nationella kontexter – arbetar forskare med att förstå dess roll i relation till medborgarskap, och det kan konstateras att genren utmanar den vetenskapliga förståelsen av politiska medier och medborgarskap. Denna Political comedy is a hybrid genre that mixes political news and analysis with comedy and entertainment. As it becomes more and more popular in most media forms and national contexts, researchers struggle to understand its role in relation to other types of political media, and of citizenship; in this sense, it challenges scholarly conceptualisation of political media and citizenship. Thus, this t

Is there an exoplanet in the Solar system?

We investigate the prospects for the capture of the proposed Planet 9 from other stars in the Sun's birth cluster. Any capture scenario must satisfy three conditions: the encounter must be more distant than ∼150 au to avoid perturbing the Kuiper belt; the other star must have a wide-orbit planet (a ≳ 100 au); the planet must be captured on to an appropriate orbit to sculpt the orbital distribution

Local interactions and protein folding : A model study on the square and triangular lattices

We study a simple heteropolymer model containing sequence-independent local interactions on both square and triangular lattices. Sticking to a two-letter code, we investigate the model for varying strength κ of the local interactions; κ=0 corresponds to the well-known HP model [K. F. Lau and K. A. Dill, Macromolecules 22, 3986 (1989)]. By exhaustive enumerations for short chains, we obtain all str

Identification of amino acid sequences with good folding properties in an off-lattice model

Folding properties of a two-dimensional toy protein model containing only two amino acid types, hydrophobic and hydrophilic, respectively, are analyzed. An efficient Monte Carlo procedure is employed to ensure that the ground states are found. The thermodynamic properties are found to be strongly sequence dependent in contrast to the kinetic ones. Hence, criteria for good folders are defined entir

Studies of an off-lattice model for protein folding : Sequence dependence and improved sampling at finite temperature

We study the thermodynamic behavior of a simple off-lattice model for protein folding. The model is two dimensional and has two different "amino acids." Using numerical simulations of all chains containing eight or ten monomers, we examine the sequence dependence at a fixed temperature. It is shown that only a few of the chains exist in unique folded state at this temperature, and the energy level

Hybrid Monte Carlo simulation of polymer chains

We develop the hybrid Monte Carlo method for simulations of single off-lattice polymer chains. We discuss implementation and choice of simulation parameters in some detail. The performance of the algorithm is tested on models for homopolymers with short- or long-range self-repulsion, using chains with 16≤N≤512 monomers. Without excessive fine tuning, we find that the computational cost grows as N2

Scaling in Steiner random surfaces

It has been suggested that the modified Steiner action functional has desirble properties for a random surface action. In this paper we investigate the scaling of the string tension and massgap in a variant of this action on dynamically triangulated random surfaces and compare the results with the gaussian plus extrinsic curvature actions that have been used previously.

Direction of arrival estimation for multiple speakers using time-frequency orthogonal signal separation

This paper presents a new approach for multiple speaker DOA estimation using an array of microphones. The method relies on the fact that multiple independent speakers have a small overlap in the time-frequency domain, i.e. the individual signals are almost W-disjoint orthogonal. By introducing a time-frequency mask and by continuously tracking the set of time-frequency points corresponding to each

Real-Time DSP Implementation of a Subband Beamforming Algorithm for Dual Microphone Speech Enhancement

A real-time digital signal processor (DSP) based implementation of a subband beamforming algorithm and its evaluation for dual microphone speech enhancement is presented. The algorithm, a calibrated constrained beamformer, is described theoretically and a real-time structure is proposed, including an efficient approach for multichannel data transformation. Measurements show that the battery driven

Effective dispersion and separation resolution in continuous particle fractionation

Theoretical models and experiments suggest that the transport of suspended particles in microfluidics-based sorting devices can be modeled by a two-dimensional effective advection-diffusion process characterized by constant average velocity, $$\mathbf {W}$$W, and a typically anisotropic dispersion tensor, $$\mathbb {D}$$D, whose principal axes are slanted with respect to the direction of the effec

Can two wrongs make it right? Reconsidering minimum resale price maintenance in the light of Allianz Hungaria

Minimum resale price maintenance (RPM) agreements constitute hard-core vertical restraints and are treated as object restrictions in EU competition law. This article suggests that the time may have come where this approach is revised. After, first, discussing the economic theory behind RPM and the EU court's approach to object restrictions, it argues that the recent widening of the object analysis