<p>The county of Dalarna is at present carrying through a process of digitalization where traditional x-ray film is being replaced with digital detectors. Earlier used methods for dose optimization turned out not being sufficient. This report presents a method to harmonize dose levels between x- ray sites equipped with Fujifilm imaging plate systems. An exposure index, S, related to the dose level of the examination is computed to every x-ray image. S turned out to be inversely proportional to the detector dose used at the examination. Detector dose is also the one simulated factor that doubtlessly affects S the most.There are however a lot of parameters, e.g difference between patients, that are not easily simulated even though they still have considerable affect. The method for harmonizing dose levels between x-ray sites are based on statistics of collected S-values for a kind of examination. The average of the collected S-values levels variations and is a more solid measure of the dose level for the examination. By means of this method the dose level of frontal images of the lungs at a site have been reduced by 30 per cent without endanger the diagnostic security.</p>

<p>The county hospital of Dalarna has for the last couple of years carried through a process of digitalization. The result is that within the county it exists image plate systems from two different manufacturers. In an attempt to create a tool for dose optimization and dose surveillance the county of Dalarna would like to investigate if the exposure index from Agfa and Fuji is suitable as a dose indicator. An investigation of the exposure index, S, from Fuji has already been done. This thesis has been continuing the investigation by evaluating the stability of the exposure index, lgM, from Agfa. Simultaneously an observation if there is a simple relation between the exposure indicators from Agfa and Fuji has been performed. The result showed that the average of lgM, for a set of images from the same type of examination, is appropriate as a dose indicator to the image plate for that specific examination type and X-ray equipment. The usefulness is linked to the same tube voltage and Speed Class for a specific examination, and is to a certain degree restricted by the collimating. There is a relation between the exposure index from Agfa and Fuji, and there is in a simple way possible to transform S-values to lgM-values for comparison. The relation turned out to be examination specific.</p>

<p>The purpose of this paper is to examine whether there is a difference between the respondent groups preparers and non-preparers position in IASBs question if a reversal of previously impaired goodwill should be prohibited. The background is an exposure draft sent out by the IASB and we examine the answers, in form of comment letters, sent in by the respondents to reach our purpose. Our method is positivistic in the sense that we study already existing theories when we create our hypothesis which gives our assumption about how the result of the respondent’s answers will be. Our data, which we have collected from the comment letters, is qualitative secondary data. When we draw our conclusions we’re using both empirics and logics, this method characterises the hypothetic-deductive method.</p><p>The theory we studied to reach our hypothesis mainly consisted of positive accounting theory, the agency theory and utility maximising theory. But we also studied existing laws, accounting standards and the special nature of goodwill as an asset to create a better understanding of how the different respondent groups would answer the question.</p><p>The result of our research showed us that more non-preparers than preparers supported IASBs proposition, but the difference between the groups was not large enough to generalize our result and we could not statistically establish any relation with help from our Chi2 test. The result that preparers to a large extent agreed with IASB is interesting because it doesn’t correspond with the theories about positive accounting theory, agency theory and the theory about utilising individuals that we have studied. From the result a few questions arise. Could it be that preparers aren’t as utilising as the theory says? Another theory that could answer this question is the stewardship theory.</p><p>Our conclusion after studying and analysing our theory and research results is that there in fact is a difference between the respondent groups preparers and non-preparers attitude towards IASBs proposal, even if the difference is smaller than we first thought.</p>

Prenatal cocaine exposure places infants at risk for developmental delays, particularly language delays (Chapman, 2000; Lester, LaGasse, & Seifer, 1998), which increase the likelihood that they will require special education services as children and show poor developmental outcomes (Delgado, Vagi, & Scott, 2006). This study used second-order latent growth curve modeling to identify the trajectory of language development of infants from 12 to 36 months of age who had completed a three-year early intervention program. This study also investigated the predictive ability of six factors related to the child, family, and intervention. Child factors included sex, birthweight, and cognitive ability at 12 months, a family factor included mother's education level, and intervention factors included intervention type and age at enrollment. Results revealed that language growth across the two-year period was quadratic, with growth declining initially, then accelerating after 24 months, compared to the nationally normed sample upon which standardized language scores were based. Being a girl, being enrolled in the program soon after birth, and having higher cognitive ability at 12 months predicted higher initial language ability. Intervention group predicted growth in language, such that both intervention groups predicted less or no initial decline compared to the primary care non-intervention group, and the center-based intervention group showed faster acceleration after 24 months compared to the home-based intervention group. Implications of these results on the research literature and practical applications were discussed.

Mixed beams of ionizing radiation in our environment originate from space, the bedrock and our own houses. Radiotherapy patients treated with boron neutron capture therapy or with high energy photons are also exposed to mixed beams of gamma radiation and neutrons. Earlier investigations have reported additivity as well as synergism (a greater than additive response) when combining radiations of different linear energy transfer. However, the outcome seemed to be dependent on the experimental setup, especially the order of irradiation and the temperature at exposure. A unique facility allowing simultaneously exposure of cells to X-rays and 241Am alpha particles at 37 ºC was constructed and characterized at the Stockholm University (Paper I). To investigate the cytogenetic response to mixed beam irradiation (graded doses of alpha particles, X-rays or a mixture of both) several different cell types were utilized. AA8 Chinese Hamster Ovary cells were analyzed for clonogenic survival (Paper I), human peripheral blood lymphocytes were analyzed for micronuclei and chromosomal aberrations (Paper II and Paper III respectively) and VH10 normal human fibroblasts were scored for gamma-H2AX foci (Paper IV). For clonogenic survival, mixed beam results were additive, while a significant synergistic effect was observed for micronuclei and chromosomal aberrations. The micronuclei dose responses were linear, and a significant synergistic effect was present at all investigated doses. From the analysis of micronuclei distributions we speculated that the synergistic effect was due to an impaired repair of X-ray induced DNA damage, a conclusion that was supported by chromosomal aberration results. Gamma-H2AX foci dose responses were additive 1 h after exposure, but the kinetics indicated that the presence of low LET-induced damage engages the DNA repair machinery, leading to a delayed repair of the more complex DNA damage induced by alpha particles. These conclusions are not necessary contradictory since fast repair does not necessarily equal correct repair. Taken together, the observed synergistic effects indicate that the risks of stochastic effects from mixed beam exposure may be higher than expected from adding the individual dose components. / <p>At the time of the doctoral defence the following papers were unpublished and had a status as follows: Paper nr 3: Manuscript; Paper nr 4: Manuscript.</p> / DNA damage and repair in cells exposed to mixed beams of radiation

An extensive use of chemicals in countless consumer products has resulted in human exposure to several persistent organic pollutants (POPs). Sufficient knowledge about their chemical composition properties and environmental faith is required, to be able to proper risk assess and regulate the substances. Significant data gaps exist regarding knowledge of actual exposure to humans and toxicological effect data. The objective of this thesis was to add human exposure data of a few POPs from four case studies. The analytes discussed in this thesis are polychlorinated dibenzo-p-dioxins and furans (PCDDs/PCDFs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD). Three European populations were studied. Milk was analysed from a group of women, who were accidentally exposed to high levels of 2,3,7,8-TetraCDD (TCDD) in Seveso, 1976. Still today, twice as high TCDD levels were recorded in the milk, compared to background concentrations. Serum was analysed from mothers and their infants from The Netherlands. Cord serum contained equal amounts of POPs as in mother’s blood, indicating non-hindered placenta transfer. Serum analysed from Swedish men and women with a high fish intake had elevated PCB and PCB metabolite (OH-PCB) levels. Additionally, butter was collected worldwide and shown to be a suitable matrix for dairy product survey of POPs. The exposure levels in the four papers were compared to recently reported exposure levels in Europe. It is indicated in the thesis that the PCDDs/PCDFs and PCBs toxic equivalency (TEQ) levels are of concern, i.e. the ratio between threshold levels for adverse health effects and TEQ exposure levels is lower than requested margin of safety. Average levels of PBDE/HBCDD in the European population are estimated to be of no concern today, but for individuals with intakes at the 95th percentile are the current margins of safety small.

The purpose of this paper is to examine whether there is a difference between the respondent groups preparers and non-preparers position in IASBs question if a reversal of previously impaired goodwill should be prohibited. The background is an exposure draft sent out by the IASB and we examine the answers, in form of comment letters, sent in by the respondents to reach our purpose. Our method is positivistic in the sense that we study already existing theories when we create our hypothesis which gives our assumption about how the result of the respondent’s answers will be. Our data, which we have collected from the comment letters, is qualitative secondary data. When we draw our conclusions we’re using both empirics and logics, this method characterises the hypothetic-deductive method. The theory we studied to reach our hypothesis mainly consisted of positive accounting theory, the agency theory and utility maximising theory. But we also studied existing laws, accounting standards and the special nature of goodwill as an asset to create a better understanding of how the different respondent groups would answer the question. The result of our research showed us that more non-preparers than preparers supported IASBs proposition, but the difference between the groups was not large enough to generalize our result and we could not statistically establish any relation with help from our Chi2 test. The result that preparers to a large extent agreed with IASB is interesting because it doesn’t correspond with the theories about positive accounting theory, agency theory and the theory about utilising individuals that we have studied. From the result a few questions arise. Could it be that preparers aren’t as utilising as the theory says? Another theory that could answer this question is the stewardship theory. Our conclusion after studying and analysing our theory and research results is that there in fact is a difference between the respondent groups preparers and non-preparers attitude towards IASBs proposal, even if the difference is smaller than we first thought.

This study was an attempt to replicate the positive results of a precognitive habituation (PH) experiment devised by Bem (2003). The procedure is based on the subliminal mere exposure (SME) design. In an SME procedure subjects are exposed to image-pairs in a preference task, after being exposed to one of those images (the target) subliminally. The target is preferred significantly more often due to the mere exposure effect. In the PH procedure the preference task precedes the exposure and images are of negative and erotic valence. It was hypothesized that due to exposure (in the future), subject preference will increase for negative and decrease for the erotic target images, especially for subjects classified erotically or negatively reactive (Bem, 2003). Also, that an overall (negative and erotic) effect would be shown. The results were not significantly above chance expectation for any of the hypotheses (50.0%; 47.2%, p = .149; 50.8%, p = .279).

Background The renewed interest in community participation in health research is linked to its potential for bridging gaps between research and practice. Its main attributes are the generation of knowledge that can lead to socially robust, long-lasting solutions and the creation of a colearner relationship between researchers and research users. Following this philosophy, Ecohealth has evolved into a specialized framework for participatory research on the impact of pollution on ecosystems and human health. However, its principles pose considerable challenges. Its outcomes are strongly influenced by contextual factors that are impossible to control for ahead of time. This paper describes how the Ecohealth principles were applied to an epidemiological study of heavy metals exposure among indigenous communities of the Peruvian Amazon. It illustrates how knowledge generated from participatory research does not necessarily imply solving a public health problem. This study aimed to contribute to the understanding of the benefits and barriers of following the basic principles of the Ecohealth approach, and assist researchers working in similar contexts. Research process Based upon their personal experience as participant observers, the authors describe the research process; then, they discuss the most important challenges faced, their implications, and the attempted strategies for resolution. Challenges Challenges were grouped into four themes: (1) building trust; (2) one partnership, many stakeholders, multiple agendas; (3) being a researcher; and (4) communicating complex and unexpected findings. Conclusions Integrating the principles of transdisciplinarity and participation posed a series of challenges to the research process that were difficult, and sometimes impossible to overcome. However, positive outcomes from this experience were the lessons learned by the different actors. Despite the lack of immediate action, it is expected that useful interventions to prevent and control lead exposure in the Corrientes population will be implemented in the medium term. / <p>Funding for the epidemiological study described in this paper came from the Comprehensive Health Care Plan for the Corrientes Native Communities (PEPISCO) and a grant from FAS, the Swedish Council for Working Life and Social Research (grant 2006–1512).</p>

No description available.