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Ultra-wideband communications using hybrid matched filter correlation receivers

Transmitted-reference (TR) schemes for time-hopping impulse radio (TH-IR) ultra-wideband (UWB) communications allow the use of simple receiver structures that are able to combine energy from different multipath components without channel estimation. A conventional TR receiver consists of a simple delay-and-multiply operation combined with an integrator. On the downside, it shows a performance loss

Participating in Synchronous Online Education

Popular Abstract in Swedish Behovet av utbildning ökar eftersom dagens anställda förväntas vara välutbildade och fortlöpande förkovra sig. Distansutbildning är ett kraftfullt sätt att möta detta behov. Nätbaserad utbildning, vilket enkelt kan definieras som distansutbildning via internet, är den vanligaste typen av distansutbildning. Inom nätbaserad utbildning är asynkron (fördröjd) kommunikation,There is an increasing need for education since the workforce of today is expected to be highly educated and continuously learn. Distance education is a powerful response to meet the growing need for education. Online education, here concisely defined as distance education mediated online, is the most common type of distance education. It mainly relies on asynchronous communication although it is

Graded effects of oxygen and respiratory inhibitors on cell metabolism and spontaneous contractions in smooth muscle of the rat portal vein

The basis for the hypoxic relaxation of spontaneous activity in the rat portal vein was investigated by comparing responses to oxygen and the respiratory chain inhibitors amobarbital and cyanide. With the inhibitors, O2 consumption (FO2) is uniformly decreased throughout the cell mass, and thus O2 gradients in the tissue are avoided. Hence the effects are not to be attributed to all-or-none inhibi

Phase Segregation in AlInP Shells on GaAs Nanowires

We have studied morphology and phase segregation of AlInP shells on GaAs nanowires. Photoluminescence measurements on single core- shell nanowires indicated variations in the shell composition, and phase segregation was confirmed by cross-sectional scanning transmission electron microscopy on 30 nm thin slices of the wires. It was discovered that Al-rich domains form in the á112ñ directions where

Performance evaluation of heart rate turbulence detection using an extended IPFM model

The well-known integral pulse frequency modulation (IPFM) model is used to generate the occurrence times of normal sinus rhythm. In a previous study, we extended the model to account for ectopic beats and subsequent variation in sinus rhythm that may accompany an ectopic beat; a phenomenon known as heart rate turbulence (HRT). Inspired by the extended model, a new approach to characterize HRT was

Alternatives for leakage reduction in a novel claw-pole electrically magnetized synchronous machine

The leakage characteristics of a novel claw-pole electrically magnetized synchronous machine are discussed in this paper. The novelty of the machine is that the magnetizing coils are placed in magnetically conducting end-plates, thus eliminating the need of slip-rings in the rotor. A previous study comparing this machine with a permanent magnet alternative showed a 20% higher leakage in the electr

Nordic biological specimen banks as basis for studies of cancer causes and control - more than 2 million sample donors, 25 million person years and 100 000 prospective cancers

The Nordic countries have a long tradition of large-scale biobanking and comprehensive, population-based health data registries linkable on unique personal identifiers, enabling follow-up studies spanning many decades. Joint Nordic biobank-based studies provide unique opportunities for longitudinal molecular epidemiological research. The purpose of the present paper is to describe the possibilitie

Effects of extracellular K+ and Ca2+ on membrane potential, contraction and 86Rb+ efflux in guinea-pig mesotubarium

The effects of varying extracellular concentrations of K+ and Ca2+ [K+]o and [Ca2+]o on force development and membrane potential were investigated in the guinea-pig mesotubarium. At [K+]o up to 40 mM, spontaneous action potentials were present, while higher [K+]o gave sustained contractures at a stable membrane potential (-24 to -12 mV for [K+]o from 60 to 120 mM). Tension decreased successively w

Photochromic pigments in akinetes and pigment characteristics of akinetes in comparison with vegetative cells of Anabaena-Variabilis

Since akinete germination is triggered by light and the action spectrum for this process has features in common with the spectra of the two photochromic pigments, phycochromes b and d, a search was made for the presence of these phycochromes in akinetes of the blue-green alga. Anabaena variabilis Kützing. Allophycocyanin-B was also looked for, since the action spectrum for akinete germination poin

X-ray parabolic lenses made from glassy carbon by means of laser

Parabolic planar compound refractive lenses (CRLs) made from glassy carbon by means of laser ablation are presented. They have radii of curvatures of 5 and 200 mu m and geometric apertures of 40 and 900 mu m, respectively. The numbers of biconcave elements in the CRLs were 4, 7, and 200. The planar lenses allow formation of a linear focus of length comparable with the depths of their profiles. Usa

The introgression of a functional nuclear gene from Poa to Festuca ovina

In sheep's fescue, Festuca ovina, genes coding for the cytosolic enzyme phosphoglucose isomerase, PGIC, are not only found at the standard locus, PgiC1, but also at a segregating second locus, PgiC2. We have used PCR-based sequencing to characterize the molecular structure and evolution of five PgiC1 and three PgiC2 alleles in F. ovina. The three PgiC2 alleles were complex in that they carried two

Treatment of C-stage and E-stage bleaching plant effluent by ultrafiltration

The influence of pH on membranes of different materials and different cut off has been studied. One ceramic microfiltration membrane and three synthetic ultrafiltration membranes were included in the study. The pH of an acidic (C-stage) and and alkaline (E-stage) bleaching effluent was varied. For the E-stage effluent the membrane performance seemed to be correlated to the cut off of the membrane.

Low parathyroid hormone levels after thyroid surgery: a feasible predictor of hypocalcemia.

BACKGROUND: Selecting patients with a low risk of hypocalcemia is mandatory if patients are to be discharged on the first day after bilateral thyroidectomy. This study investigated the predictive value of intraoperative parathyroid hormone (PTH). METHODS: Thirty-eight patients underwent total or near-total thyroidectomy. Patients with or without biochemical and symptomatic hypocalcemia were compar

Basic fibroblast growth factor for stimulation of bone formation in osteoinductive and conductive implants

Popular Abstract in Swedish Basic Fibroblast Growth Factor (bFGF) är en av flera tillväxtfaktorer som finns lagrad i benvävnaden. bFGF framkallar celldelning och tillväxt hos många olika celltyper, däribland benceller (osteoblaster) och broskceller. bFGF kan stimulera till nybildning av blodkärl och även benvävnad. I denna avhandling undersökes om utifrån tillfört bFGF kan öka benbildning och vävnBasic Fibroblast Growth Factor (bFGF) is one of the endogenous factors found in bone matrix. bFGF is a mitogen for many cell types, including osteoblasts and chondrocytes. It can stimulate angiogenesis and osteoblast gene expression. The purpose of this study was to investigate whether exogenous bFGF can stimulate the formation of bone in bone grafts and in a bone graft substitute. All experiments