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We study a system of spherical non-adsorbing particles immersed in a polydisperse polymer fluid. We derive an analytic expression for the many-body depletion interactions between the colloidal particles in the limit of very long chains. We argue that this expression is essentially exact for long chains and justify this using explicit simulations. In this way we are able to elucidate the profound e

I förra veckan antog Svenska Akademien en ny kommentar till sina stadgar. Där menade man att det ligger närmast till hands att jämföra Akademien med privaträttsliga organisationer. Men frågan är om man inte borde ha jämfört sig mer med de statliga institutionerna.

Objective: Systemic sclerosis (SSc) is a major cause of pulmonary arterial hypertension (PAH). Murine models indicate key roles for chemokines CCL19 and CCL21 and their receptor CCR7 in lung inflammation leading to PAH. The objective of this study was to assess the chemokine CCL19–CCL21 axis in patients with SSc-related PAH. Methods: Serum samples obtained from 2 independent prospective SSc cohort

Martin Sunnqvist reflekterar över olika aspekter som rör rättsstaten. Hur byggs en rättsstat upp? Hur bryts en rättsstat ned? Den första frågan har lett till att fri- och rättigheter, oavhängiga domstolar, författningsdomstolar och självständiga advokatväsenden har införts i många länder. Nu måste den motsatta frågan ställas, så att varningsklockorna kan identifieras.

During recent years, many sites with sediments pre-dating the Last Glacial Maximum have been identified in formerly glaciated areas. As more and better dates are presented from these sites, the dynamic behaviour of the Scandinavian Ice Sheet is becoming increasingly clear. In this study, we revisited the site Skorgenes in western Norway. Here, sediments from two ice-free periods are found below an

Megacephalosaurus eulerti is a large macropredatory plesiosaur representing one of the last members of the diverse pliosaurid clade Brachaucheninae. The taxon was established upon a nearly complete skull including the mandible and fragments of the postcranial skeleton originating from the lower middle Turonian (Upper Cretaceous) of Kansas, USA. Owing to its age, reasonable completeness and its sta

Purpose: Patients with acromegaly have an increased risk of sleep apnea, but reported prevalence rates vary largely. Here we aimed to evaluate the sleep apnea prevalence in a large national cohort of patients with acromegaly, to examine possible risk factors, and to assess the proportion of patients diagnosed with sleep apnea prior to acromegaly diagnosis. Methods: Cross-sectional multicenter stud

This study grounds a highly charged debate on agriculture in developing countries within economic theory, by establishing a structured analytical framework for considering the potential role of foreign investment in supporting agricultural development. The framework is developed to be time and space neutral, such that it can be utilized in various geographic settings and across different time peri

This paper shows an application of continuous-time system identification methods to Type 1 diabetes. First, a general MISO transfer function structure with individual nominator and denominator polynomials for each input is assumed and a parameter estimation procedure via an iterative prediction error method presented. Then, the proposed identification method is evaluated on a simple simulation exa

A drilling task requires a mechanism with five degrees of freedom, in order to achieve the correct position and orientation of the drilling tool. When performed with a standard 6-axes industrial robot, this task leaves an extra degree of freedom that can be exploited in order to achieve any additional criterion. Unfortunately, typical industrial robotic control architectures do not allow the user

Modern industrial robots are fast and have very good repetitional accuracy, which have made them indispensable in many manufacturing applications. However, they are usually programmed to follow desired trajectories and only get feedback from position sensors. This works fine as long as the environment is very well structured, but does not give good robustness to objects not being positioned or gri

This contribution reviews theory, algorithms, and validation results for system identification of continuous-time state-space models from finite input-output sequences. The algorithms developed are autoregressive methods, methods of subspace-based model identification and stochastic realization adapted to the continuous-time context. The resulting model can be decomposed into an input-output model

The focus of this article is to undertake a comparative analysis of multi-step-ahead linear multivariate predictors. The approach considered for the estimation will be based on geometrically reliable linear algebra tools, resorting to subspace identification methods. A crucial issue is quantification of both bias error and variance affecting the estimate of the prediction for increasing values of

The well-known and commonly accepted finite dimensional model qualitatively describing surge instabilities in centrifugal (and axial) compressors is considered. The problem of global output feedback stabilization for it is solved. The solution relies on two new criteria for global stability proposed for a class of nonlinear systems exploiting quadratic constraints for infinite sector nonlinearitie

This paper presents theory, algorithms and validation results for system identification of continuous-time state-space models from finite non-uniformly sampled input-output sequences. The algorithms developed are methods of model identification and stochastic realization adapted to the continuous-time model context using non-uniformly sampled input-output data. The resulting model can be decompose

Using methods of system identification and prediction, we investigate near-future prediction of individual specific T1DM blood glucose dynamics with the purpose of a decision-making tool development in diabetes treatment. Two strategies were approached: Firstly, Kalman estimators based on identified state-space models were designed; Secondly, direct identification of ARX- and ARMAX-based predictor

Stability problems associated with robot control with obstacle avoidance are analyzed.Obstacle avoidance algorithms based on potential function are revised to accomplish stable re-design. A stability proof using Lyapunov theory and passivity theory is provided for the re-designed obstacle avoidance algorithm. The paper presents a modification of potential functions for obstacle avoidance aiming to