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Purpose: The platelet-derived growth factor (PDGF) signalling pathway is often dysregulated in cancer and PDGF-receptor expression has been linked to unfavourable prognostic factors in breast cancer (e.g. ER negativity, high Ki67 and high grade). This study aimed to evaluate the expression of PDGFRα, PDGFRβ and ligand PDGF-CC in breast cancer in relation to molecular subtypes and prognosis. Method

Vad kan du se när du tittar upp nattetid? Stjärnor, planeter, månen, kanske även stjärnfall? Känner du igen några stjärnbilder?I denna interaktiva planetariumföreställning bjuder vi våra yngsta besökare på en upptäcktsfärd bland natthimlens stjärnor innan vi lämnar Jorden och flyger ut i rymden för att tillsammans besöka solsystemets olika planeter.What can you see when you look up at night? Stars, planets, the Moon, maybe even a shooting star? Do you know any of the constellations?In this interactive planetarium show we invite your youngest visitors to explore the night sky and to fly out into the Solar System to visit the planets.

Studies on the acquisition of French liaison have primarily focused on monolingual children or adult second language (L2) learners in a university context. To bridge the gap between these two populations, the present article focuses on child L2 (cL2) learners – a particularly interesting group, since they are L2 learners who, unlike adults, do not have access to writing. How does liaison develop i

Mycket forskning inom olika vetenskapsområden har länge haft fokus på social­tjänstens insatser för barn i olika avseenden och även på privatiseringen av verkstäligheten av vården. Det saknas däremot studier som fokuserar på förekomsten av privata konsulter som genomför barnavårdsutredningar. Det innebär också att det idag är oklart vilka konsekvenser en sådan förändring innebär för socialtjänsten

We study the behavior of the multiphoton ionization rate of He+ ions as a function of the perturbation order N. By comparing the N-, (N+1)-,..., (N+S)-photon ionization processes, we prove that the absorption of photon in the continuum spectrum is increased at the largest wavelengths.

We present experimental results of harmonic generation using a 1-ps 1015-W/cm2 Nd-glass laser. We see up to the 29th harmonic in Xe, 57th in Ar, and at least up to the 135th harmonic in Ne (160 eV), being then limited by our monochromator's resolution. The conversion efficiencies in Xe, Ar, Ne, and He are compared and different ways of optimizing the number of photons by defocusing the laser beam

The authors have calculated two-photon electron detachment cross sections of the 5p shell of negative iodine in the photon energy region 0-1 Ryd. The results cover the region from the two-photon ionisation threshold of I - at 0.12 Ryd to well above the one-photon ionisation threshold of neutral iodine at about 0.8 Ryd. They demonstrate the importance of many-electron screening effects and double e

We investigate different processes which may be responsible for ejection of two electrons from the external shell of xenon through the absorption of two and three photons, namely two-photon direct double ionization and three-photon sequential double ionization via the ion in an excited state or in the ground state. We calculate the cross sections of the ionization processes involved, using many-bo

The authors present calculations of the two-photon one-electron ionisation of the 5p shell of xenon including non-linear response. Screening effects are described within the random-phase approximation (RPA). The authors use both a local-density approximation (LDA) and a Hartree-Fock average basis set. They describe a large energy region from the two-photon ionisation threshold to above the one-pho

The recent advances concerning high-order harmonic generation processes in strong laser fields are discussed. We show how the width of the plateau inherent to the production of high harmonics varies with the pulse width, the laser wavelength and the atomic medium. Phase matching effects are discussed in terms of coherence length owing to the laser focusing. Finally, we show that the idea of genera

We apply the random-phase approximation to two-photon ionization. We develop a formalism which, by means of screened electron-photon interactions, includes the nonlinear response and, in particular, double-excitation processes. The theory is illustrated by numerical calculations of the two-photon ionization cross section of the external (5p and 5s) shell of xenon, over a large energy range: from t

We present experimental results of harmonic generation at 1064 nm using a 36-ps neodymium-doped yttrium aluminum garnet laser tightly focused in a gas jet of xenon. The harmonic yields are studied as a function of the position of the focus in the jet at several laser intensities and as a function of intensity at several focus positions. These results bring information about how the high harmonics

We review the main experimental results obtained in the multielectron multiphoton ionization of rare gases. Multiple ionization is interpretated as a sequential process. We study the influence of many‐electron effects in multiphoton ionization within the framework of the random phase approximation. This is applied to a calculation of the two‐photon ionization cross section of xenon. Finally, the r

Multielectron ionization of Xe is described in terms of multistep processes, driven by a laser field which is screened by the motion of the outer 5p shell. In stepwise multiple ionization of the 5p shell, screening is successively reduced. The effective, local intensity will therefore increase during the stripping of the outer shell. In the 4d inner-shell region the effective intensity is very low

We study the influence of many-electron effects in multiphoton ionization within the framework of diagrammatic many-body perturbation theory. We renormalize the electron-dipole coupling by summing to infinite order both many-electron interactions using the random-phase approximation and higher-order intensity terms. We introduce an effective intensity, which takes into account the screening of the