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Introduction: The main route of excretion of activity for most administered radiopharmaceuticals is via the urinary bladder and it is important to estimate the absorbed dose to the mucosal surface of the bladder wall, especially when radiopharmaceuticals are given for therapeutic purposes. The purpose of this thesis was to investigate how the absorbed dose varies with changes in the parameters, wh

Hals- och huvudregionen innehåller många luftkaviteter t.ex. luftstrupe, bihålor och munhåla. Detta arbete undersökte vad som händer i vävnaden kring dessa luftkaviteter när de blir bestrålade med fotoner och hur bra ett dosplaneringssystem för strålbehandling modellerar den absorberade dosen till ett heterogent medium. Dosberäkningarna gjordes med hjälp av ett Monte Carlo-simuleringsprogram somPurpose: To study the build-down and build up of the absorbed dose at the interface between air and tissue in the head and neck region. Monte Carlo simulations are compared to a treatment planning system that is used at the University Hospital in Lund. Materials and methods A virtual phantom was constructed to resemble an air cavity in the head and neck region. The phantom consisted of a water cyl

Varje år får cirka 50 000 svenskar diagnosen cancer. Mot detta är strålbehandling en vanlig behandlingsmetod och det uppskattas att cirka en tredjedel av alla som får cancer någon gång under sin behandling får strålbehandling. En viktig sak inom strålbehandling är att patienten får den dos som läkaren har ordinerat. Detta är en så vital detalj inom strålbehandling att SSI, Statens StrålskyddsinsIndependent dose calculations in radiotherapy are important as they help assure that the dose given to the patient is the same as the prescribed. The current version of software Radiation Verification Programme, RVP, does not take into account the effects that occur when a beam from a linear accelerator is moved off-axis. The aim with this project was to find a model for these effects, fit the par

Kvaliteten på kliniska bilder har stor betydelse för korrekt medicinsk diagnostik. I konventionella morfologiska MR-bilder är signalen normalt relativt hög i förhållande till bruset. Vissa nya MR-metoder för s.k. funktionsdiagnostik bygger emellertid på en avsiktlig degradering av signalen för att vissa kvantitativa parametrar skall kunna beräknas. I sådana studier kan följaktligen signal-till-bruNoise is a well-known problem in many imaging modalities. In magnitude magnetic resonance images, obtained by quadrature detection, the associated Rician distribution of noise constitutes a further complication. This type of noise is especially problematic at low signal-to-noise ratio (SNR) regions. The Rician noise distribution causes a non-zero minimum signal in the image, often referred to as t

Determination of absolute activity of 99mTc and 123I in organs for the purpose of patient-specific dosimetry in nuclear medicine examinations and therapy is of great importance. In order to make accurate quantification of the organ content from planar gamma camera images of phantoms, several corrections has to be made. The accuracy of a number of correction methods and different combinations of th

Introduction: To our knowledge a biomedical model for validation of combined MicroPET/MicroCAT studies of the thyroid with 124I has not yet been developed. Such an in vivo physiological rat model could be of great interest for enhancing the possibilities of studying common thyroid diseases realistically and repeatedly. Furthermore, a well developed, realistic, and flexible model can also be of gre

This work shows a contribution to a long-term study of lead in smelter workers where the objectives were to assess the historical lead (Pb) exposure and to study the relationships between lead concentrations in finger bone (Bone-Pb), whole blood (B-Pb), plasma (P-Pb), urine (U-Pb) and the duration of employment in workers at a secondary lead smelter. Moreover, results were compared with previous s

Syftet med denna studie var att utvärdera säkerhetsmarginalerna som läggs kring ett målorgan (tex prostata) vid extern strålterapi. Resultaten kan senare ligga till grund för reducering av säkerhetsmarginalerna, detta för att skydda strål-känslig frisk vävnad från onödig bestrålning. En delstudie var också att försöka finna ett mönster hos prostatans rörelse vid de inledande behandlingstillfällena"Introduction: This thesis is a study of the margins that are necessary in prostate cancer radio therapy treatment. The aim was to analyse the intrafraction motion of the prostate gland during treatment, by the use of portal imaging, in order to optimize the margin around the prostate gland and spare healthy tissue. One of the purposes was to find a common pattern in prostate movement in the

The purpose with this diploma work is to find solutions that facilitate the manual demining process by designing tools and equipment used by manual deminers. Manual demining is a part of humanitarian demining that has been neglected for a long time even though its a vital part of mine action programs around the world and very important for humanitarian demining in general. The main idea is to prov

This paper examines the income differentials and characteristics relevant to the labour market of East-West migrants, West Germans and East-German stayers in Germany in 2006. This is done by using descriptive statistics as well as regression models based on the Human Capital theory by Becker and Mincer. The data used in this paper comes from the Socio-Economic Panel (SOEP) of the German Institute

This thesis investigates the role states play in promoting and directing a country’s development. More specifically, it is examined, which factors determine differences in state performance and why different types of states form. This is done through a comparative case study of Botswana and Zambia, two southern African countries that after a similar start into independence developed very different

Det är i mötet – idag framför allt det medierade mötet – mellan journalisten och politikern som nyheter om politik uppstår och som vi medborgare bygger merparten av våra uppfattningar om politiken kring. Som en ingrediens i detta möte kan medieträning ha betydelse för vad som sker och sägs. Medieträning som bruk och verktyg är dock ömsom ifrågasatt och kritiserat, ömsom förklarat som nödvändigt i

Improving an inhalation device so that the patient has full control of his health status, is the #1 objective of the project. Being a futuristic project, carried out from a patien's prespective, the ambition is still to perform a realistic industrial design assignment. The project concentrates on aesthetical qualities, as well as matching them with the fundamental functions of the device. Th