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Picosecond dynamics in a millimetre-wave RTD-MOSFET wavelet generator

The performance of a millimetre-wave wavelet generator under picosecond-pulsed trigger operation conditions has been evaluated experimentally. The reactively-loaded resonant tunnelling diodes metal-oxide-semiconductor field-effect-transistor circuit is shown to generate well-formed wavelets for control pulse-lengths down to approximately the free-running carrier oscillation period. Transient circu

A class of non-Gaussian second order random fields

Non-Gaussian stochastic fields are introduced by means of integrals with respect to independently scattered stochastic measures distributed according to generalized Laplace laws. In particular, we discuss stationary second order random fields that, as opposed to their Gaussian counterpart, have a possibility of accounting for asymmetry and heavier tails. Additionally to this greater flexibility th

Some historic and current aspects of plasma diagnostics using atomic spectroscopy

In this paper we give a short introduction to the use of atomic spectroscopy in plasma diagnostics. Both older works and exciting new branches of atomic physics, which have relevance to diagnostics, are discussed. In particular we focus on forbidden lines in Be-like ions, lines sensitive to magnetic fields and levels which have a lifetime dependence on the nuclear spin of the ion, i.e. f-dependent

Breast cancer risk in women who fulfill high-risk criteria: at what age should surveillance start?

Family history is a strong predictor of hereditary breast cancer, particularly when it includes cases of early onset or bilateral breast cancers and multiple cases of breast or ovarian cancers. This article provides relative risks and cumulative risks of breast cancer in women whose family history indicates high risk. Specifically, the aim was to determine how many years earlier the high-risk wome

Human Embryonic Stem Cell-Derived Mesenchymal Stroma Cells (hES-MSCs) Engraft In Vivo and Support Hematopoiesis without Suppressing Immune Function: Implications for Off-The Shelf ES-MSC Therapies.

Mesenchymal stroma cells (MSCs) have a high potential for novel cell therapy approaches in clinical transplantation. Commonly used bone marrow-derived MSCs (BM-MSCs), however, have a restricted proliferative capacity and cultures are difficult to standardize. Recently developed human embryonic stem cell-derived mesenchymal stroma cells (hES-MSCs) might represent an alternative and unlimited source

From Euler to Navier-Stokes: A Spatial Analysis of Conceptual Changes in Nineteenth-century Fluid Dynamics

This article provides a spatial analysis of the conceptual framework of fluid dynamics during the nineteenth century, focusing on the transition from the Euler equation to the Navier-Stokes equation. A dynamic version of Peter Gardenfors's theory of conceptual spaces is applied which distinguishes changes of five types: addition and deletion of special laws; change of metric; change in importance;

Musculoskeletal disorders in demanding computer work - with air traffic control as a model

In computer work, musculoskeletal disorders are frequently reported, but the knowledge about causal relationships is limited. In air traffic control, female and male operators perform exactly the same computer work. Introduction of a new computer system implied a momentary change from a “varied” system containing different in-put devices, to a system characterized by intensive mouse-work. The effe

Real-Time Gas-Phase Imaging over a Pd(110) Catalyst during CO Oxidation by Means of Planar Laser-Induced Fluorescence.

The gas composition surrounding a catalytic sample has direct impact on its surface structure, which is essential when in situ investigations of model catalysts are performed. Herein a study of the gas phase close to a Pd(110) surface during CO oxidation under semirealistic conditions is presented. Images of the gas phase, provided by planar laser-induced fluorescence, clearly visualize the format

Vertebral Scheuermann's disease in Europe: prevalence, geographic variation and radiological correlates in men and women aged 50 and over

The Summary In 27 centres across Europe, the prevalence of deforming spinal Scheuermann's disease in age-stratified population-based samples of over 10,000 men and women aged 50+ averaged 8 % in each sex, but was highly variable between centres. Low DXA BMD was un-associated with Scheuermann's, helping the differential diagnosis from osteoporosis. Introduction This study aims to assess the prevale

Parenthood and factors that influence outdoor recreational physical activity from a gender perspective

Background: A physically active life promotes both physical and mental health, increasing well-being and quality of life. Physical activity (PA) performed outdoors has been found to be particularly good for promoting well-being. However, participation in PA can change during the course of a lifetime. Parenthood has been found to be a life event associated with decreased PA, especially among women,

Coordinated unbundling: A way to stimulate entrepreneurship through public procurement for innovation

Public procurement for innovation is a matter of using public demand to trigger innovation. Empirical studies have demonstrated that demand-based policy instruments can be considered to be a powerful tool in stimulating innovative processes among existing firms. However, the existing literature has not focused on the role this policy instrument can play in the promotion of (knowledge-intensive) en

Svensk bröllopsdiktning under 1600- och 1700-talen

Recension av: Stina Hansson, Svensk bröllopsdiktning under 1600- och 1700-talen. Renässansrepertoarernas framväxt, blomstring och tillbakagång (Göteborg: Institutionen för litteratur, idéhistoria och religion, Göteborgs universitet, 2011). 526 s.

Dynamic response of chlorine atoms on a RuO2(110) model catalyst surface

The dynamic behavior of surface accommodated chlorine atoms on RuO2(110) was studied by a variety of experimental methods including high resolution core level shift, thermal desorption-, and in situ infrared spectroscopy as well as in situ surface X-ray diffraction in combination with state-of-the-art density functional theory calculations. On the chlorinated RuO2(110) surface the undercoordinated

Measuring Electoral Systems

This article compares and assesses four freely available cross-sectional time-series data sets in terms of their information on ballot structure, district structure, and formula of the electoral system in use for lower house and, if relevant, upper house and presidential elections. The authors find that the choice of data source matters for conclusions drawn on the consequences of electoral system

Genetic variation in the invasive avian parasite, Philornis downsi (Diptera, Muscidae) on the Galapagos archipelago

BACKGROUND: Understanding the dispersal and genetic structure of invasive insects across islands is important for designing management plans that are appropriate at spatial and temporal scales. For invasive parasites, population dynamics are largely determined by the distribution and density of their host species. The introduced parasitic fly, Philornis downsi, parasitises nestlings of endemic bir

Fetal scalp blood sampling during labor: an appraisal of the physiological basis and scientific evidence

Fetal cardiotocography is characterized by low specificity; therefore, in an attempt to ensure fetal well-being, fetal scalp blood sampling has been recommended by most obstetric societies in the case of a non-reassuring cardiotocography. The scientific agreement on the evidence for using fetal scalp blood sampling to decrease the rate of operative delivery for fetal distress is ambiguous. Based o