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Optoelectric spin injection in semiconductor heterostructures without a ferromagnet

We have shown that electron-spin density can be generated by a dc current flowing across a pn junction with an embedded asymmetric quantum well. Spin polarization is created in the quantum well by radiative electron-hole recombination when the conduction electron momentum distribution is shifted with respect to the momentum distribution of holes in the spin-split valence subbands. Spin current app

Improved convergence rate for the simulation of stochastic differential equations driven by subordinated Levy processes

We consider the Euler approximation of stochastic differential equations (SDEs) driven by Levy processes in the case where we cannot simulate the increments of the driving process exactly. In some cases, where the driving process Y is a subordinated stable process, i.e., Y = Z(V) with V a subordinator and Z a stable process, we propose an approximation Y by Z(V-n) where V-n is an approximation of

JastAdd - an aspect-oriented compiler construction system

We describe JastAdd, a Java-based system for compiler construction. JastAdd is centered around an object-oriented representation of the abstract syntax tree where reference variables can be used to link together different parts of the tree. JastAdd supports the combination of declarative techniques (using Reference Attributed Grammars) and imperative techniques (using ordinary Java code) in implem

Service transformation - managing a shift from business travel to virtual meetings

It has been shown that the potential for environmental, and financial improvements through the increased substitution of inperson meetings by virtual communication is considerable. However, it has also been shown that this potential is not automatically realized by investing in the technology that can enable virtual meetings. This paper describes two case studies that explored the factors that inf

Flying with the wind - Spring migration of Arctic-breeding waders and geese over South Sweden

Spring migration of arctic breeding birds, mainly waders and Dark-bellied Brent Geese Branta bernicla, was followed by tracking radar in Lund, South Sweden, during 1998-2001 in order to evaluate the capacity of these birds to exploit favourable winds. A total of 888 radar tracks were collected. Here I report on measured flight speeds, flight altitudes and winds and compare these with results from

Combustion Diagnostics by Means of Multizone Heat Release Analysis and NO Calculation

In this paper a combustion diagnostic method is presented where measured pressure data is used to calculate the heat release, local temperatures and concentrations of NO and other species. This is done by a multizone model where the lambda value, i.e. 1/equivalence ratio, in each zone can be chosen arbitrarily. In homogenous charge engines lambda is given by the global air/fuel ratio. The local la

Female genital mutilation in the West: traditional circumcision versus genital cosmetic surgery.

This article intends to present the Scandinavian legislation on female genital mutilation and explore the implications of the laws. Juxtaposing trends of plastic genital surgery in the West with claims that female circumcision may be a practice generally abandoned in Scandinavia, we highlight the double morality inherent in current public discussions. Finally, we pose the question: Is the legal pr

Effects of nine different gastrointestinal polypeptides on vascular smooth muscle in vitro

Nine polypeptides of gastrointestinal origin were tested for their possible effect on vascular smooth muscle of the rat portal vein. The substances tested were bombesin, caerulein, glucagon, insulin, pentagastrin, secretin, somatostatin, substance P and vasoactive intestinal polypeptide (VIP). Cumulative dose-response relations of integrated mechanical activity (mean tension) were obtained with ma

Serial digital autoradiography with a silicon strip detector as a high resolution imaging modality for TRT Dosimetry

This study aims to investigate the possibility of implementing serial autoradiography using a silicon strip detector as an imaging modality in pre-clinical radionuclide therapy research, in order to study the effect of non-uniform uptake on absorbed dose distribution and biological response. Tumor tissues expressing CD20 (B-cell lymphoma) or carcinoembryonic antigen (CEA; colorectal cancer) were e

Measurement and QCD analysis of neutral and charged current cross sections at HERA

The inclusive e(+)p single and double differential cross sections for neutral and charged current processes axe measured with the H1 detector at HERA. The data were taken in 1999 and 2000 at a centre-of-mass energy of roots = 319 GeV and correspond to an integrated luminosity of 65.2 pb(-1). The cross sections are measured in the range of four-momentum transfer squared Q(2) between 100 and 30 000

Solvent effects on rotatory strength tensors. 1. Theory and application of the combined coupled cluster/dielectric continuum model

In this article we present the first theoretical study of solvent effects on the rotatory strength tensor. The system chosen is solvated formaldehyde for which only one tensor element is nonvanishing, and the solvent is modeled as a linear, homogeneous, and isotropic dielectric continuum. We present results using both an equilibrium and a nonequilibrium description of the solvent. Four illustrativ

Macrophages from high-risk HLA-DQB1*0201/*0302 type 1 diabetes mellitus patients are hypersensitive to lipopolysaccharide stimulation.

Levels of nonantigen-induced pro-inflammatory cytokines and prostaglandin in macrophages isolated from human leucocyte antigen (HLA)-matched type 1 diabetes mellitus patients, first-degree relatives and healthy controls were determined. We hypothesize that monocytes isolated from patients are sensitized or preactivated and therefore, have an altered response to in vitro stimulus compared with cont