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Linear MMSE estimation of time-frequency variant channels for MIMO-OFDM systems

This paper proposes two low-complexity two-dimensional channel estimators for MIMO-OFDM systems derived from a joint time–frequency channel estimator. The estimators exploit both time and frequency correlations of the wireless channel via use of Slepian-basis expansions. The computational saving comes from replacing a two-dimensional Slepian-basis expansion with two serially concatenated one-dimen

INVESTIGATION OF PARTIAL VOLUME EFFECT IN DIFFERENT PET/CT SYSTEMS: A COMPARISON OF RESULTS USING THE MADEIRA PHANTOM AND THE NEMA NU-2 2001 PHANTOM.

Positron emission tomography combined with computed tomography (PET/CT) is a quantitative technique used for diagnosing various diseases and for monitoring treatment response for different types of tumours. However, the accuracy of the data is limited by the spatial resolution of the system. In addition, the so-called partial volume effect (PVE) causes a blurring of image structures, which in turn

Treatment of chronic hepatitis B infection: An update of Swedish recommendations

The main goal for treatment of chronic hepatitis B is to prevent complications such as liver cirrhosis or hepatocellular carcinoma. Knowledge from population studies of the long-term risk of chronic HBV infection, as well as the recent introduction of pegylated interferon and additional nucleoside analogues has changed the therapeutic situation. Recently, a Swedish expert panel convened to update

Prediction of Survival of Metastatic Prostate Cancer Based on Early Serial Measurements of Prostate Specific Antigen and Alkaline Phosphatase

PURPOSE: We determined how serial measurements of prostate specific antigen and alkaline phosphatase can be used to predict survival early in the course of hormone treated metastatic prostate cancer. MATERIALS AND METHODS: The study was based on a prospective randomized trial of 915 patients with metastatic prostate carcinoma designed to compare parenteral estrogen (polyestradiol phosphate) vs tot

3-year follow-up of 215 fracture patients from a prospective and consecutive osteoporosis screening program. Fracture patients care!

BACKGROUND AND PURPOSE: Fractures can be prevented if osteoporosis is identified and treated. Starting in 2002, we have been using a screening program in which patients between 50 and 75 years of age with a wrist, shoulder, vertebral, or hip fracture are assessed by DEXA of the hip and spine and if osteoporotic or osteopenic, they are encouraged to see a doctor of their own choice. The patients re

Visual ergonomics interventions in mail sorting facilities

This study was performed between 2004 and 2011 at mail sorting facilities in Sweden. During this time, different interventions were performed. The first was a lighting intervention that had a positive impact on the postal workers, especially those with eyestrain. A new lighting system also improved the illuminance and gave better light distribution. The second intervention involved new personal sp

Generalization of n-ary Nambu algebras and beyond

The aim of this paper is to introduce n-ary Hom-algebra structures generalizing the n-ary algebras of Lie type including n-ary Nambu algebras, n-ary Nambu-Lie algebras and n-ary Lie algebras, and n-ary algebras of associative type including n-ary totally associative and n-ary partially associative algebras. We provide examples of the new structures and present some properties and construction theo

Urban NO2 and NO pollution in relation to the North Atlantic Oscillation NAO

The North Atlantic Oscillation (NAO), a measure of the strength of the zonal wind across the North Atlantic Ocean, strongly influences weather conditions in NW Europe, e.g. temperature, precipitation and wind, especially during winter. It was hypothesised that elevated concentrations of nitrogen oxides in Gothenburg would be enhanced during negative NAO index (NAOI) conditions, representing more a

An Epidemiological Study of Exhaustion in the Context of Chronic stress. Concept, Cortisol, Causes and Consequences

Popular Abstract in Swedish Intresset för utmattning har ökat både i Sverige och internationellt under de senaste årtiondena. Utmattning som begrepp är oklart definierat vetenskapligt, och det finns olika benämningar på utmattningstillstånd, som till exempel den något gammalmodiga benämningen neurasteni, som ännu finns kvar som diagnos-klassifikation (där även benämnt ”trötthetssyndrom”), kronisktThe interest in exhaustion has increased rapidly during the last few decades in many developed countries. In Sweden, prevalence of exhaustion increased by 50 percent on average between 1989 and 2005, and recent data reveals that exhaustion still remains at this higher level. Scientifically, exhaustion is not clearly defined. Chronic stress is acknowledged to give rise to exhaustion, but specific m

Investigating the mechanisms for the opposing pH relationships of fungal and bacterial growth in soil

Soil pH is one of the most influential variables in soil, and is a powerful factor in influencing the size, activity and community structure of the soil microbial community. It was previously shown in a century old artificial pH gradient in an arable soil (pH 4.0-8.3) that bacterial growth is positively related to pH, while fungal growth increases with decreasing pH. In an attempt to elucidate som

Commissioning of the ATLAS Muon Spectrometer with cosmic rays

The ATLAS detector at the Large Hadron Collider has collected several hundred million cosmic ray events during 2008 and 2009. These data were used to commission the Muon Spectrometer and to study the performance of the trigger and tracking chambers, their alignment, the detector control system, the data acquisition and the analysis programs. We present the performance in the relevant parameters th

Burial in the Swedish-Norwegian Battle Axe Culture : questioning the myth of homogeneity

Since its publication in 1962, Mats P. Malmer’s book Jungneolithische Studien has heavily influenced subsequent work on the Swedish-Norwegian Battle Axe Culture. Malmer characterized burial customs as strictly regulated and conservative. Recent archaeological activity in the province of Scania, southern Sweden, provides us with an augmented empirical basis for testing Malmer’s conclusions. In addi

Social context modulates basic properties of oculomotor control

Experiments performed in a lab are often considered generali- zable over both people and social settings. The problems with generalizing over different groups of people are well known, but it is only recently that changes in behavior depending on thesocial setting have been examined. Large changes in behavior can be seen in trivial cognitive tasks, depending on whether the participant is alone or

Divergent composition but similar function of soil food webs of individual plants: plant species and community effects

Soils are extremely rich in biodiversity, and soil organisms play pivotal roles in supporting terrestrial life, but the role that individual plants and plant communities play in influencing the diversity and functioning of soil food webs remains highly debated. Plants, as primary producers and providers of resources to the soil food web, are of vital importance for the composition, structure, and

Search for heavy neutrinos and right-handed W bosons in events with two leptons and jets in pp collisions at root s=7 TeV with the ATLAS detector

This letter reports on a search for hypothetical heavy neutrinos, N, and right-handed gauge bosons, W-R, in events with high transverse momentum objects which include two reconstructed leptons and at least one hadronic jet. The results were obtained from data corresponding to an integrated luminosity of 2.1 fb(-1) collected in proton-proton collisions at root s = 7 TeV with the ATLAS detector at t

Gas spectroscopy and optical path-length assessment in scattering media using a frequency-modulated continuous-wave diode laser

Simultaneous assessment of the spectroscopic absorption signal of gas enclosed in a scattering medium and the corresponding optical path length of the probing light is demonstrated using a single setup. Sensitive gas absorption measurements are performed by a tunable diode laser using wavelength-modulation spectroscopy, while the path length is evaluated by the frequency-modulated cw technique com

On the complexity of approximating the Hadwiger number

Unless P = NP there is no polynomial time approximation scheme (PTAS) for the problem of finding, for a graph G, the largest h such that the complete graph K-h is a minor of G. (C) 2008 Elsevier B.V. All rights reserved.

A Second Replicated Quantitative Analysis of Fault Distributions in Complex Software Systems

Background. Software engineering is in search for general principles that apply across contexts, for example to help guide software quality assurance. Fenton and Ohlsson presented such observations on fault distributions, which have been replicated once. Objectives.We intend to replicate their study a second time in a new environment. Method.We conducted a close replication, collecting defect data

Deformation and mixing of coexisting shapes in neutron-deficient polonium isotopes

Coulomb-excitation experiments are performed with postaccelerated beams of neutron-deficient Po-196,Po-198,Po-200,Po-202 isotopes at the REX-ISOLDE facility. A set of matrix elements, coupling the low-lying states in these isotopes, is extracted. In the two heaviest isotopes, Po-196,Po-198, the transitional and diagonal matrix elements of the 2(1)(+) state are determined. In Po-196,Po-198 multiste

Identification, Validation and Implementation of Blastemal Biomarkers in Wilms Tumour

Popular Abstract in Swedish Wilms tumör eller nefroblastom är en njurtumör som drabbar 10-15 barn i Sverige varje år. Majoriteten av dessa är under sex år vid insjuknandet och 10 % av de som drabbas överlever inte sjukdomen. Tumören består oftast av tre stycken cellkomponenter: blastem, epitel och stroma. Dessa komponenter kan finnas av olika mängd i tumören. Om en tumör består av mer än 2/3 av nåThe aim of this thesis has been to establish biomarkers for the blastemal element in Wilms tumour (WT) – the most common paediatric kidney cancer. Blastema is, together with epithelium and stroma, one of the three common histological elements of WT. WTs dominated by blastema after preoperative chemotherapy are classified as high risk tumours. According to the SIOP2001 protocol used in most Europea