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Dosimetric verification of synthetic CT using Cone Beam CT in an MRI only workflow

En tredjedel av de män som diagnostiseras med cancer i Sverige idag diagnostiseras med prostatacancer. Prostatacancer är den vanligaste förkommande cancerformen i Sverige. Det finns flera behandlingsmetoder för prostatacancer, en utav dem är extern strålbehandling. Vid behandling med denna metod bestrålas prostatan med en strålkälla som befinner sig utanför kroppen. En liten stråldos ges vid fleraBackground and purpose: The MRI only workflow aims to base the treatment planning solely on magnetic resonance imaging (MRI), hence excluding the traditional computed tomography (CT) scan. To do that synthetic computed tomography (sCT) data is generated, replacing the conventional CT data. The aim of this study was to investigate the possibility of using cone beam computed tomography (CBCT) images

NaCl pellets for improved dosimetry

Det finns alltid en strävan att kunna uppskatta stråldoser på bättre och mer effektiva sätt. Om det så handlar om människor som blivit exponerade för joniserande strålning vid en olycka, ett attentat med radioaktiva ämnen eller för att mäta stråldoser på t ex. sjukhus. Idag finns det många kommersiellt tillgängliga alternativ för att utföra dosmätningar, så kallade dosimetrar. Samtidigt hade det vThere is always a need to improve and develop new ways of estimating effective doses to people and environments that have been exposed to ionizing radiation. Dose monitoring is also important in hospitals and the nuclear industry. Today there are several commercially available dosimeters, the most common being thermoluminescent dosimeters, TLDs, made from LiF. These are widely used for personal do

Sensitivity analysis and calibration of multi energy balance land surface model parameters

Jorden tar emot ett konstant flöde av energi via solinstrålning som sedan cirkulerar mellan atmosfären, haven och markytan innan den slutligen strålas ut i rymden. Dessa energiflöden är bränslet som driver planetens väder- och klimatfenomen och det vetenskapliga samfundet efterfrågar ökad kunskap om detta system för att utmaningarna med klimatförändringar ska kunna förutspås och hanteras. En grundFlows of energy between the atmosphere, the oceans and the land surfaces drive weather and climate on Earth. Increased understanding of these processes is crucial to successfully predict and address the challenges of climate change. Land surface models (LSM) are mathematical models designed to mimic natural processes and evolution of land surfaces with the basic task to simulate surface-atmosphere

‘Partner in Prime’? Effects of Repeated Mobile Security Priming on Mood, Attachment Security and Perceived Stress in Daily Life

Secure attachment representations, rooted in experiences with primary caregivers in early childhood, are considered a fundamental resource for a happy and healthy life. According to meta-analytical data, every third adult does not have secure attachment representations. Lacking secure attachment representations is associated with numerous health-related problems, perhaps mediated by increased susc

Embedding gender in the business and human rights agenda

All businesses have a responsibility to respect human rights, including women’s rights. Whilst the UN Guiding Principles on Business and Human Rights acknowledge the vulnerabilities of women in the global value chains, there is limited guidance on what measures corporations should take in order to avoid and address women specific harms. Taking a rights-based approach to gender equality, this study

Finding Field of View Overlap by Motion Analysis

Network cameras has in the recent years become more powerful. Each camera is independent and has its own surveillance task. It is reasonable that network cameras in the future should cooperate together to increase surveillance effectiveness. There is a need to find cameras sharing the same field of view in order for an operator to switch perspective. This thesis investigates how multiple network c

Assessing Japan’s renewable energy situation: Can the Feed-In Tariff policy and the Energy grid situation constrain the future of renewable energy in Japan?

This thesis uses the principal-agent theory to analyse two interconnected problems within the Japan’s renewable energy sector, namely the Feed-in Tariff (FIT) policy, and the energy grid issue. Following the Fukushima accident, while the nuclear power plants remained closed, Japan’s renewable energy sector was able to experience enormous growth. The number of applicants for the FIT was greater tha

Simulation and analysis of InP/GaInP nanowire Esaki diodes for photovoltaic device applications

In this thesis the WKB-approximation is used to simulate the tunneling current for an Esaki nanowire diode and the result is compared to data from Esaki nanowire diodes grown with MOVPE. The WKB-approximation with triangular potential barrier predicts a strong increase of the tunneling current as a function of the doping densities and at the highest doping levels it gives lower tunneling distances

En flytande fråga - Om dagvatten i plan- och byggprocessen

Kommunernas arbete för att ta hand om dagvattnet är intressant då klimatanpassning har uppmärksammats på en nationell nivå. Parallellt arbetar många skånska kommuner för en förtätning av den bebyggda miljön. Utmaningen med förtätning ligger i att ju mer bebyggelse och infrastruktur det byggs desto mindre ytor för infiltration lämnas kvar och desto större tryck skapas på det befintliga va-nätet närMany municipalities plan for urban infill development to fulfill the housing needs and diminish urban sprawl. Without a good planning approach, urban infill brings more impervious areas and smaller green areas that can take care of stormwater. This creates pressure on the existing drainage system when heavy rains fall. Thus, there is a risk for urban flooding if those aspects are not taken into co

Master thesis on fast charger connector solution

Volvo Construction Equipment are investigating new machine concept that involve fast charging with high power. This should be done automatically and independent on humans. The thesis set out to develop and design a complete system solution for this, including the connector and the automated system for connection. The thesis is based on previous projects presented at LTH in various mechatronics cou

Diffusion-adapted spatial filtering of fMRI data for improved activation mapping in white matter

Brain activation mapping using fMRI data has been mostly focused on finding detections in gray matter. Activations in white matter are harder to detect due to anatomical differences between both tissue types, which are rarely acknowledged in experimental design. However, recent publications have started to show evidence for the possibility of detecting meaningful activations in white matter. The s

Current Ripple Simulation in DC Traction Voltage System of an Electric Bus: 2

Current ripple can cause a lot of problems as it spreads in the DC-side of the TVS of electric and electric hybrid vehicles. Fully knowing the properties of the TVS can be used to build a simulation model to determine the spreading of current ripple beforehand, which in turn is useful for calculating component placement, optimal filter sizes, and component lifetime. Being the second in line of an

Kompletterande styrsystem för vattenburna värmesystem i flerbostadshus - Kartläggning av styrsystem och erfarenheter

Idag är det många äldre flerbostadshus som står inför behov av renovering och energieffektivisering. Äldre byggnader har en betydligt högre energianvändning, för uppvärmning och varmvatten, än dagen nybyggda byggnader. Uppvärmningen av lokaler och bostäder svarade år 2014 för ungefär 35 procent av den totala energianvändningen. I kombination av en ökad urbanisering och ett renoveringsbehov av äldr

Implementation of control algorithm for mechanical image stabilization

Cameras mounted on boats and in other similar environments can be hard to use if waves and wind cause unwanted motions of the camera which disturbs the desired image. However, this is a problem that can be fixed by applying mechanical image stabilization which is the goal of this thesis. The mechanical image stabilization is achieved by controlling two stepper motors in a pan-tilt-zoom (PTZ) camer

Capsaicin biosynthesis in baker’s yeast Saccharomyces cerevisiae

Background: Capsaicinoids are the compounds responsible for the pungent taste in the chili pepper genus capsicum. They are potent agonists of TRPV-receptors have large potential to be used as pharmaceutical agents for the treatment of various disease conditions associated to the peripheral and central nervous systems. Capsaicinoids are synthesized by the acylation of the aromatic compound vanillyl

Incomplete Oxidation of Bio-butanol To Bio-butyraldehyde Using Gluconobacter oxydans DSM 2343

Until now we still depend on oil and natural gas to supply us with fuels and other chemicals as a foundation to our economic advance. The global population is expected to reach 9 billion by 2050. With increasing population, the oil resource consumption will also increase, and an alternative source must be found and developed to supply us with chemicals and fuel needed for our economical advances,

Common genetic polymorphisms in manganese transporters SLC30A10, SLC39A8 and SLC39A14, manganese concentrations and neurological function

Genetics for Manganese Manganese (Mn) is one of the essential minerals for humans and it is mainly present in blood, liver, intestine, and brain. However, at elevated concentrations, for example from occupational or environmental exposure, Mn may be toxic to the nervous system. Despite that Mn concentrations are tightly regulated in the body, concentrations seem to depend on our genetics. The ai

Att vinna kriget utanför slagfältet i antikens Grekland och Rom - Generalerna berättar

”How to win the war outside of the battlefield in ancient Greece and Rome – the generals explain” The purpose of this thesis is to shed some light on the topic of psychological warfare in two ancient, war-describing texts: The History of the Peloponnesian War, written by Thucydides, and The Commentaries on the Gallic War, written by Julius Caesar. The main reason behind this lays in modern approa

A Song as a Nation Brand

This study aims to give an overview of how nation branding is organised in the Netherlands by analysing the collaboration of individual institutions involved in nation branding and the so called ‘Holland Branding Collective’. Nation branding in the Netherlands is a fragmented field where institutions approach nation branding bottom-up with a combination of public and private actors. There are seve

An overview of EFB usage in Scandinavia - discrepancies between EASA’s recommendations and operators’ implementation

The use of Electronic Flight Bags (EFBs) have become widespread and common among a majority of commercial airlines in Scandinavia and the United States in recent years. This development was enabled by modernized rules and regulations and the availability of suitable and affordable commercial-off-the-shelf (COTS) devices. This bachelor thesis studied EFB usage and user experience among pilots in com