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Experimental micro-mechanics of granular media studied by x-ray tomography: Recent results and challenges

Combining x-ray tomography and three-dimensional (3D) image analysis has finally opened the way for experimental micro-(geo)mechanics, allowing access to different scales of interest. When these correspond to a scale that has been imaged at high spatial resolution, high-quality measurements can be obtained (e.g. 3D displacements and rotations of individual grains of sand sample under load). Howeve

Dubbelt upp om Wallenberg

Recension av Ingrid Carlberg, ”Det står ett rum här och väntar på dig…” Berättelsen om Raoul Wallenberg och Bengt Jangfeldt, Raoul Wallenberg – en biografi.

Intelligensaristokrater och arkivmartyrer : normerna för vetenskaplig skicklighet i svensk historieforskning 1900–1945

The dissertation deals with the construction of norms of academic excellence in the Swedish discipline of history 1900-1945. The area of focus is the competition for professorial chairs in history. The legacy of the discipline viewed history as a holistic concept, binding together most humanistic disciplines. From the perspective of this legacy, the view of empirical specialization was becoming in

A peace treaty for the rationality wars? External validity and its relation to normative and descriptive theories of rationality

If we know that certain ways of making decisions are associated with real-life success, is this then how we should decide? In this paper the relationship between normative and descriptive theories of decision-making is examined. First, it is shown that the history of the decision sciences ensures that it is impossible to separate descriptive theories from normative ones. Second, recent psychologic

Visualizing overdamped wavepacket motion: Excited-state isomerization of pseudocyanine in viscous solvents

The isomerization of 1,1'-diethyl-2,2'-cyanine iodide in n-alcohols is studied by femtosecond pump-probe spectroscopy. Using a broad range of probe wavelengths, the dynamics of ground-state bleach recovery, excited-state absorption and stimulation emission are monitored. We attributed the observed spectral evolution to the excited-state torsional motion, which occurs in a barrierless fashion in al

A general search for new phenomena at HERA

A model-independent search for deviations from the Standard Model prediction is performed using the full e(+/-) p data sample collected by the H1 experiment at HERA. All event topologies involving isolated electrons, photons, muons, neutrinos and jets with transverse momenta above 20 GeV are investigated in a single analysis. Events are assigned to exclusive classes according to their final state.

Masked Depth Culling for Graphics Hardware

Hierarchical depth culling is an important optimization, which is present in all modern high performance graphics processors. We present a novel culling algorithm based on a layered depth representation, with a per-sample mask indicating which layer each sample belongs to. Our algorithm is feed forward in nature in contrast to previous work, which rely on a delayed feedback loop. It is simple to i

MOVPE-grownInAs/AlAs0.16Sb0.84/InAs and InAs/AlAs0.16Sb0.84/GaSb heterostructures

We demonstrate MOVPE-growth of InAs/AlAs0.16Sb0.84/GaSb and InAs/AlAs0.16Sb0.84/InAs heterostructures of excellent quality as observed by transmission electron microscopy and x-ray diffraction 2-theta-omega and rocking curve scans with full width at half maximum routinely below 100 arcsec. Key points regarding interface control for heteroepitaxial nucleation are reviewed and the choice of suitable

Density-induced reentrant melting of colloidal Wigner crystals.

Electrostatic repulsions can drive crystallization in many-particle systems. For charged colloidal systems, the phase boundaries as well as crystal structure are highly tunable by experimental parameters such as salt concentration and pH. By using projections of the colloid-ion mixture to a system of (soft) repulsive spheres and the one-component plasma (OCP), we study the hitherto unexplained exp

Speakers Comfort and voice disorders in classrooms

Lärare har stora röstkrav i sitt arbete och deras röst är det viktigaste redskapet för kommunikationen med eleverna. Projektet har undersökt lärares röstanvändning och rösthälsa i relation till bl.a. undervisningslokalens akustiska förutsättningar. Projektets olika delar har genomförts med gott resultat: En studie av förekomsten av röstproblem med 467 lärarna visar att 13% av lärargruppen har prob

The rise and fall of GO trading in European renewable energy policy: The role of advocacy and policy framing

This paper examines policy processes surrounding the rise and fall of the proposed EU-wide policy instrument designed to help achieve EU´s renewable energy targets – the trading of Guarantees of Origin (GO). It discusses its origins and examines factors in the policy processes over time leading first to its development and then to its rejection. A first analysis looks at the near-term policy-makin

Evolution of Prey Polymorphism Induced by Learning Predators

A prey species using crypsis to avoid predators has the opportunity to evolve polymorphic crypsis when it is being exposed to two (or more) habitats with different backgrounds. Here, we investigate when this phenomenon can occur, in a simulation study with a sexually reproducing prey and a predator that can learn to find hiding prey, represented by an artificial neural network. Initially, the prey

Progress in treatment and risk stratification of neuroblastoma: Impact on future clinical and basic research.

Close international collaboration between pediatric oncologists has led to marked improvements in the cure of patients, seen as a long-term overall survival rate of about 80%. Despite this progress, neuroblastoma remains a challenging disease for both clinicians and researchers. Major clinical problems include lack of acceptable cure rates in high-risk neuroblastoma and potential overtreatment of

Leukocyte count and incidence of subarachnoid haemorrhage: a prospective cohort study.

Subarachnoid haemorrhage (SAH) is a devastating disease, in the majority of cases caused by a rupture of an arterial intracranial aneurysm. The effect of systemic low-grade inflammation on incidence of SAH is not known. The purpose of this study was to evaluate the relationship between leukocyte count, a marker of systemic inflammation, and incidence of SAH in a large cohort study.

Subthalamic deep brain stimulation improves smooth pursuit and saccade performance in patients with Parkinson's disease.

Deep brain stimulation (DBS) in the subthalamic nucleus (STN) significantly reduces symptoms of Parkinson's disease (PD) such as bradykinesia, tremor and rigidity. It also reduces the need for anti-PD medication, and thereby potential side-effects of L-Dopa. Although DBS in the STN is a highly effective therapeutic intervention in PD, its mechanism and effects on oculomotor eye movement control an

Sekulariseringen av eschaton

The article engages in the critical debates over the utopian aspects of the Western heritage that took place in the wake of the Second World War. A striking feature of these debates is how thinkers from the entire political spectra – from Georg Lukács to Isaiah Berlin and Eric Voegelin – made very similar analyses, although they draw quite different conclusions. Hence all of them blamed German Rom

Differences in muscle activity during hand-dexterity tasks between women with arthritis and a healthy reference group

Background: Impaired hand function is common in patients with arthritis and it affects performance of daily activities; thus, hand exercises are recommended. There is little information on the extent to which the disease affects activation of the flexor and extensor muscles during these hand-dexterity tasks. The purpose of this study was to compare muscle activation during such tasks in subjects w

Estimation of turbulent fragmenting forces in a high-pressure homogenizer from computational fluid dynamics

The aim of this study was to find models for turbulent fragmenting forces in the high-pressure homogeniser from data available in Computational Fluid Dynamics (CFD) simulations with Reynolds Averaged Navier Stokes (RANS) turbulence models. In addition to the more common RANS k-epsilon turbulence models, a Multi-scale k-epsilon model was tested since experimental investigations of the geometry impl