Sammanfattning Bakgrund Stråldosen vid en datortomografiundersökning (CT-undersökning) kan vara 100 gånger större än vid en konventionell röntgenundersökning [1]. På 10 år har antalet CT-undersökningar nästan fördubblats [2], vilket också innebär att stråldosen till patienterna ökar [1]. Bröstkörtlarna är ett av de mest strålkänsliga organen och är därför viktiga att skydda [3, 4]. Material som dämpar röntgenstrålning kraftigt och som lämpar sig för strålskydd är t.ex. bly och vismut [5].

24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the Radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..

Several radioactive nuclides were deposited in Sweden after the Chernobyl accident in 1986. The greatest attention was given to 137Cs because of its relative long physical half life of about 30 years. 137Cs will be present in nature for more than 100 years before it has vanished completely. When radiocaesium decays to a stable end product ionizing Radiation is emitted, which can cause cancer in humans that has been exposed to a high Radiation dose. Radiocaesium behaves like potassium and is easily taken up into biological systems.

Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water. Radioactive Radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.

The tomato is an important crop worldwide, and in recent years it has received great attention due to its rich content of carotenoids, which in studies indicate to have health benefiting properties. Many studies have been done in this area of research and in how to optimize the carotenoid content in tomatoes and tomato products. The objectives of this essay were to summarize present data in this field. The results were as follows:There are nine different carotenoids identified in tomatoes. Lycopene and ?-carotene are the ones that have been given the greatest attention.

The urban heat island is an area restricted to a city center where the temperatureis higher than its surrounding environment. The greatest temperature difference isfound at night when the weather is calm and the sky is clear of clouds. There are twomajor causes behind this phenomena and the first one is the use of energy forheating of houses. The heat leaks through the walls of the buildings and warms upthe surrounding mass of air. The second one is the use of building material whichstore the suns Radiation on daytime and releases the heat during night.

In this Thesis the possibilities of designing a larger building that is very energy efficient in the sense that it would not need a conventional heating system are discussed. Solar Radiation transmitted through the windows, internal heat from occupants, lamps and electric appliances inside the building and heat recovered from the ventilation system then have to be sufficient for the heating of the building. This study is of general interest since the property company, Akademiska Hus, plans to use this study as a first step in determining if this technique could be used in the future and thus be worth further investments. A building without a conventional heating system of the size investigated in this project has not yet been built.The energy needed for the heating of the building was simulated using VIP+.The conclusions from the study are that it is possible to build large buildings without any conventional heating system. This could be achieved in many different ways, for example by lowering the inside temperature or by using better windows and heat recovery system with higher efficiency.

This bachelors thesis was made forWallenius Water AB to develop a basisfor an Airpurifier prototype. Wallenius Water isone of the world's leading environmentaltechnology companies engaged inchemical-free water treatment based onUV-Radiation. The thesis aim was toproduce a basis for a prototype that canbe used in three applications:Standalone, RAS systems and ventilationsystems. The work includes anintroductory description of the theorybehind AOP technology based on aliterature review on the subject. Asurvey of products currently on themarket and a product specification hasbeen used as the basis for thepreparation of a number of concepts inthis report.

The tomato is an important crop worldwide, and in recent years it has received great attention due to its rich content of carotenoids, which in studies indicate to have health benefiting properties. Many studies have been done in this area of research and in how to optimize the carotenoid content in tomatoes and tomato products. The objectives of this essay were to summarize present data in this field. The results were as follows:There are nine different carotenoids identified in tomatoes. Lycopene and ?-carotene are the ones that have been given the greatest attention.

The tomato is an important crop worldwide, and in recent years it has received great attention due to its rich content of carotenoids, which in studies indicate to have health benefiting properties. Many studies have been done in this area of research and in how to optimize the carotenoid content in tomatoes and tomato products. The objectives of this essay were to summarize present data in this field. The results were as follows:There are nine different carotenoids identified in tomatoes. Lycopene and ?-carotene are the ones that have been given the greatest attention.

This is a master degree thesis at Royal Institute of Technology (KTH) betweenÅngpanneföreningen and Programma. KTH is the examiner, Programma is the client andÅngpanneföreningen is mentor for this project.Programma has a product called TM1800 that has problems with EMC; the problem is thatthis product does only pass the CE-check with a small safety margin. This problem can besolved by reducing the Radiation from the electric components in the product or by reducing offix base frame. In this degree thesis the focus is only on mechanical redesign.The main problems right now depends on the long distance between the screws, there is anisolating layer on most of the parts and the forces between the joints are too small. The mainfocus is to solve these three problems.The best solutions are when the whole base frame is more or less redesigned instead of onlyredesigning some of the connection points.

This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as Radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse.

Background: Every year, 2000 persons in Sweden are diagnosed with malignant melanoma, the most alarming form of skincancer. Sunexposure, sunburns and tanningbed use are the most appearing causes in the development of this disease. The skin of young people is sensitive to UV-Radiation and their sunbehaviour could be determinant to their future health. Purpose: To illuminate the knowledge and attitudes of adolescents towards sunexposure in the meaning to avoid the development of malignant melanoma. Method: The study was designed to be a literature review, containing scientific articles of both qualitative and quantitative approach.

Sverige är för tillfället operativa med Helikopter 16 - Black Hawk i Afghanistan. Uppgiften som löses i Afghanistan är främre och taktisk sjuktransport (MEDEVAC).Detta arbete handlar om hur befintliga VMS-system i helikoptrar kan kompletteras i syfte att möta ett föreliggande prickskyttehot vid lösande av främre MEDEVAC i ett insatsområde som miljömässigt liknar Afghanistan. I arbetet analyseras möjliga tekniker utifrån aspekter från ett konstruerat scenario där helikopterbesättningarnas uppgift, insatsmiljö samt hotbild beskrivs.Resultatet visar på att MEDEVAC-helikoptrar kan utrustas med sensor-gimbaler där olika sensorer kan kombineras, vilket möjliggör spaning i 360°. Detta bidrar till den militära nyttan då helikopterpersonalens lösande av uppgift effektiviseras, chansen till överlevnad ökar samtidigt som personal och patienter kan känna sig tryggare..