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Varje år diagnostiseras i Sverige ungefär 1100 personer med cancer i huvudhalsregionen. Typiska diagnoser är tungcancer, läppcancer och cancer i struphuvudet. I och runt om munhålan finns det stora skillnader i densitet mellan till exempel vävnad och tänder och vävnad och tandlagningar. I detta arbete så har effekterna av ett antal olika tandlagningsmaterial på dosberäkningarna undersökts. För a"Introduction: Around 1.000 people are diagnosed with head and neck cancer in Sweden every year. Radiotherapy is often used to treat these tumors. When irradiating patients in the head and neck area there are some problems. One of these problems is the large difference in density between the oral tissue and dental materials. Another problem is the image artifacts due to high-density materials

Monte Carlo-simuleringar har fått en ökad betydelse som forskningsverktyg inom nuklearmedicinsk bildgivning eftersom man på ett mycket kontrollerat sätt kan studera nästan vad man vill. I denna studie har datorsimuleringar av ett PET-system gjorts med ett program som heter GATE. PET (Positron Emission Tomography) är en nuklearmedicinsk bildgivningsteknik som används mer och mer inom sjukvården sIntroduction: Monte Carlo simulation is a powerful tool in research in the field of nuclear medicine imaging and there is a wide area of applications. The purpose of this work was (1) to understand the basics of the Monte Carlo simulation software Geant4 Application for Tomographic Emission (GATE); (2) to create a model of Philips Gemini TF PET/CT system; (3) to run a number of simulations to comp

MAX-lab is a national synchrotron radiation facility in Lund. Nowadays, the MAX project consist of three facilities (three storage rings). A new storage ring is needed to improve material science, such as nanotechnology. MAX IV, also in Lund, will be 100 times more efficient than already existing synchrotron radiation facilities. The storage ring is controlled by a large number of magnets that are

With an increasingly population and urbanization, the solid waste management have become a major challenge for local authorities in developing countries all over the world. The local authorities must improve their waste management in order to minimize the negative effects of solid waste and to avoid future land use conflicts. At the same time the economical resources are limited and solid waste ma

Dealing with water diffuse pollution is a major problem for watershed managers. This problem raises many complicated questions, which are important to answer in order to reach water environment protection goals. This study suggested some possible answers for the country of Lithuania. Among them were the identification of critical source areas, the identification of sensitive areas and the applicat

Dwarf galaxies are a key component in understanding the evolution of galaxies and provide tests on the standard cosmological $\Lambda$ Cold Dark Matter model. According to the formation hierarchy, dwarf galaxies are the pieces that create all galaxies. Our current understanding of dwarf galaxies faces discrepancies between theory and observations. These problems are mostly due to incompleteness in

Background: Neuropsychiatric symptoms (NPS) are common in individuals with Alzheimer’s disease (AD) dementia, but substantial heterogeneity exists in the manifestation of NPS. Sex differences may explain this clinical variability. We aimed to investigate the sex differences in the prevalence and severity of NPS in AD dementia. Methods: Literature searches were conducted in Embase, MEDLINE/PubMed,

Background: Hepatitis B virus infection is a global health problem with the highest prevalence in East Asia and Sub-Saharan Africa. The majority of infected people, including healthcare workers are unaware of their status. This study is aimed to determining seroprevalence of hepatitis B virus infection and associated factors among healthcare workers in northern Tanzania. Methods: This cross-sectio

BACKGROUND: The major risk factors for atherosclerotic cardiovascular disease differ by race or ethnicity but have largely been defined using populations of European ancestry. Despite the rising prevalence of cardiovascular disease in Africa there are few related data from African populations. Therefore, we compared the association of established cardiovascular risk factors with carotid-intima med

During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO 2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we charact

Background and Objectives: There is considerable heterogeneity in the association between increasing β-amyloid (Aβ) pathology and early cognitive dysfunction in preclinical Alzheimer disease (AD). At this stage, some individuals show no signs of cognitive dysfunction, while others show clear signs of decline. The factors explaining this heterogeneity are particularly important for understanding pr

BACKGROUND: Osteoarthritis is a leading cause of disability worldwide. Current treatment supports coping strategies to improve health-related quality of life (HRQoL). The need to predict response to treatment has been raised to personalise care. This study aims to examine change in HRQoL from baseline to three and nine months follow-up after participating in a Supported Osteoarthritis Self-Managem

The aim of this work was to develop a model suited for detailed studies of aerosol dynamics, gas and particle phase chemistry within urban plumes, from local scale (1x1 km(2)) to regional scale. This article describes and evaluates the trajectory model for Aerosol Dynamics, gas and particle phase CHEMistry and radiative transfer (AD-CHEM). The model treats both vertical and horizontal dispersion p

Background: Cardiovascular Magnetic Resonance (CMR) enables non-invasive quantification of cardiac output (CO) and thereby cardiac index (CI, CO indexed to body surface area). The aim of this study was to establish if CI decreases with age and compare the values to CI for athletes and for patients with congestive heart failure (CHF). Methods: CI was measured in 144 healthy volunteers (39 +/- 16 ye

The source contributions to carbonaceous PM2.5 aerosol were investigated at a European background site at the edge of the Po Valley, in Northern Italy, during the period January-December 2007. Carbonaceous aerosol was described as the sum of 8 source components: primary (1) and secondary (2) biomass burning organic carbon, biomass burning elemental carbon (3), primary (4) and secondary (5) fossil

Background: Several attempts to increase the locoregional control in locally advanced lung cancer including concurrent chemotherapy, accelerated fractionation and dose escalation have been made during the last years. As the EGFR directed antibody cetuximab has shown activity concurrent with radiotherapy in squamous cell carcinoma of the head and neck, as well as in stage IV NSCLC combined with che

This article presents a fully integrated millimeter-wave (mmW) transceiver front end covering 24.25–29.5 GHz. It features a wideband Doherty power amplifier utilizing adaptive bias and a transmit/receive switch (TRX-switch) that has embedded low noise amplifier to antenna matching. The phase shift of 90 $^\circ$ to

Background: Gallbladder cancer (GBC) is rare but aggressive. The extent of surgical intervention for different GBC stages is non-uniform, ranging from cholecystectomy alone to extended resections including major hepatectomy, resection of adjacent organs and routine extrahepatic bile duct resection (EBDR). Robust evidence here is lacking, however, and survival benefit poorly defined. This study ass

Background: Previous studies demonstrated increases in diagnostic confidence and change in patient management after amyloid-PET. However, studies investigating longitudinal outcomes over an extended period of time are limited. Therefore, we aimed to investigate clinical outcomes up to 9 years after amyloid-PET to support the clinical validity of the imaging technique. Methods: We analyzed longitud

Background: In sub-Saharan Africa, truckers and female sex workers (FSWs) have high HIV risk and face challenges accessing HIV testing. Adding HIV self-testing (HIVST) to standard of care (SOC) programs increases testing rates. However, the underlying mechanisms are not fully understood. HIVST may decrease barriers (inconvenient clinic hours, confidentiality concerns) and thus we would expect a gr