Bakgrund: Ambulanssjuksköterskan hamnar ofta i situationer där samverkan med andra organisationer är nödvändig. På en skadeplats leds arbetet av både ambulans, räddningstjänst och polis. För att detta arbete ska flyta på och främja patient omhändertagandet krävs det en god samverkan mellan dessa organisationer. Forskning visar på att trots att alla parter vill samverka sker detta inte alltid då varje organisation arbetar var för sig trots den tydliga viljan att samverka gränslöst.  Syfte: Att beskriva ambulanssjuksköterskors upplevelse av samverkan mellan blåljuspersonal på skadeplats. Metod: Metoden som användes i denna studie var en kvalitativ intervjustudie. Det genomfördes 15 semistrukturerade intervjuer som sedan transkriberades och sammanfördes till ett resultat genom ett kvalitativt induktivt tillvägagångssätt enligt Elo och Kyngäs metod. Resultat: Resultatet pekar på att samverkan mellan blåljuspersonal oftast fungerar väldigt bra men att det finns brister. De brister som framkom var framförallt i kommunikationen. Det var även viktigt att ha någon form av personkännedom, detta för att lättare känna en sammanhållning mellan organisationerna.  Inte bara vi och dem utan mer en gemenskap, en teamkänsla. Slutsats: Samverkan mellan blåljusorganisationerna sker på bästa sätt när arbetet följer de strukturer och koncept som finns samt när organisationerna strävar efter samma mål. En tydlighet i både kommunikation och ledarskap är viktigt för att få arbete att gå framåt. / Bakgrund: Ambulanssjuksköterskan befinner sig ofta i situationer där samarbete med andra yrken är nödvändigt. På en olycksplats leds arbetet av både ambulans, räddningstjänst och polis. För att göra detta arbete flytande och tillräckligt för patientsäkerheten måste de tre organisationerna arbeta tillsammans. Även om forskning visar att organisationerna vill arbeta tillsammans är det inte alltid så. Varje organisation arbetar för sig själv trots viljan att samarbeta och göra gränsen mellan organisationerna mer gränslös. Syfte: Att beskriva ambulanssjuksköterskors erfarenhet av samarbeten mellan akutorganisationer på olycksplatsen. Metod: Metoden i denna studie var en kvalitativ intervjustudie. Femton semistrukturerade intervjuer genomfördes, som sedan transkriberades och kombinerades till ett resultat genom en kvalitativ induktiv ansats enligt Elo och Kyngäs metod. Resultat: Resultaten som framkom visade att samverkan mellan räddningspersonal oftast fungerar mycket bra men att det finns brister. Bristerna var främst när det gällde kommunikation. Det var också viktigt att ha någon form av personlig kunskap till varandra, detta för att göra det lättare att känna en sammanhållning mellan yrkesgrupperna. Inte bara de och vi, mer en gemenskap där arbetet görs som ett team. Slutsats: Samverkan mellan akutorganisationerna är som mest flytande när arbetet följer befintliga strukturer och koncept och när organisationerna strävar efter samma mål. Tydlighet i både kommunikation och ledarskap är viktigt för att arbetet ska gå smidigt.

Part 1: Monitoring Response to Single-Dose (1000cGy) Radiotherapy in a RIF-1 Tumor Model The current standard of measure for monitoring chemotherapeutic and radiotherapeutic treatment response is tumor volume. Unfortunately, changes in tumor volume are generally slow and tumor volume does not necessarily indicate the degree of tumor viability. The development of marker(s) with the ability to detect an early therapeutic response would greatly aid in patient management, opening the possibility for both rapid dose optimization and replacement of ineffective therapies with alternative treatment. Previous studies have shown that diffusion measurements using magnetic resonance imaging (MRI) techniques are sensitive to therapy-induced changes in cellular structure, allowing demarcation between regions of necrosis and viable tumor tissue. This sensitivity, based on the correlation between water apparent diffusion coefficient (ADC) values and tumor cellular density, may allow diffusion measurements to be employed in non-invasive monitoring of treatment response. Therapy-induced increases in tumor ADC preceding tumor regression have been reported in a variety of experimental tumor models and several human brain tumors. Despite the demonstrated diffusion sensitivity to therapeutic response in these particular studies, shortcomings still remain that hinder the efficacy of clinical application in oncology. Earlier studies have concentrated on the mean ADC present within the tumor, either within the entire tumor volume or a region of-interest (ROI) defined by the user, and their evolution pre-treatment and post-treatment. Because of inter- and intra-tumor heterogeneity, volume-averaged ADC measurements suffer from poor correlation with treatment efficacy. In addition, most studies make little or no attempt to characterize the entire tumor volume (necrotic, viable, edema). The identification of regions of differing tissue viability should aid in the staging of treatment, therefore making accurate and reproducible tissue segmentation an important goal. The results of earlier, single-parameter studies indicate that a multi-parametric approach in which several MR parameters are monitored (ADC, T2, M0) may provide greater power than that of the single parameter approach. A multi-parametric or multi-spectral (MS) analysis uses pattern-recognition techniques, such as clustering, for image segmentation. Clustering algorithms use characteristics of the multiple MR-parameter dataset to group tissue of similar type, e.g., fat, muscle, viable tumor, necrosis. Specifically, k-means (KM) is an unsupervised segmentation algorithm that groups together similar tissue based on the difference in MR parameter space between the image voxel of interest and the mean parameter values of the voxels in that cluster. In the first step of the classification algorithm, it is applied to separate the data into two clusters (k = 2), tissue and background noise voxels. All voxels classified as background noise are set to zero and removed from further processing. In the second step, KM is applied to the remaining tissue voxels to segment the data into multiple tissue types. In the case of tumors, it is not clear in advance how many different types of tissue exist. The number of clusters, k, should be varied to ensure that all relationships between tissues are found. In the final step, the resulting KM maps may be compared to histological slices taken from the same tissue as the imaging slices in order to identify the tissue type of each cluster. In line with the studies and analyses described above, quantitative MRI was performed to investigate the spatial correlation between ADC, spin-spin (T2) relaxation times, and proton density (M0) in murine radiation-induced fibrosarcoma (RIF-1) tumors following single-dose (l000cGy) radiotherapy using the KM algorithm (Chapters 3 and 4) and different combinations of features and/or clusters. For all cluster/feature combinations, an in-depth comparison between KM-derived volume estimates and conventional histology via the hematoxylin-eosin (H&E) staining procedure (for identification of viable tumor versus necrosis), as well as via hypoxic-inducible factor-lα. (HIF-1α) immunohistochemistry (for identification of regions of hypoxia versus well-oxygenated tissue) was performed (Chapter 3). The optimal cluster/feature combination was determined by minimizing the sum-of-squared-differences (SSD) between the actual datapoints and the ideal one-to-one correlation that should exist between KM-derived volume estimates and histology-derived volume estimates. The optimal cluster/feature combination was determined to be a 2-feature (ADC, T2) and 4-c1uster (2 regions each of viable tissue and necrosis) segmentation. This KM method was then applied in analysis of the radiotherapeutic response: first, to gain insight into the various processes whose combination yield the total ADC response over time; second, to identify the contribution of tissue heterogeneity to the treatment response and changes in tumor growth kinetics and cell kill (Chapter 4). Comparisons between control and various time-points out to 14 days post-radiotherapy permitted more accurate tissue characterization and prediction of therapeutic outcome over analysis using ADC alone. The results based on histological validation demonstrated: (1) MS analysis provides an improved tissue segmentation method over results obtained from conventional methods employing ADC alone; (2) MS analysis permits subdivision based on the degree of necrosis, as well as delineation between well-oxygenated and hypoxic viable tissue; and (3) Individual KM volumes corresponded well with both H&E volumes and regions with increased HIF-1α expression. The results based on the radiotherapeutic response demonstrated: (1) MS analysis provides a method for monitoring the range of tissue viability as a function of time post-treatment; (2) MS analysis permits assessment of the various contributions to the total ADC response post-treatment; (3) The relative fractions of well-oxygenated (i.e., radiosensitive) versus hypoxic (i.e., radioresistant) tissue pretreatment may be predictive of treatment response; and (4) The early ADC increase did not seem to be a result of radiation-induced vasogenic edema, but instead was most likely due to a slight reduction in cellular density following therapy. These studies provide a non-invasive method of tissue characterization that may be used in monitoring treatment response and optimizing drug dose-timing schemes, with the potential for predicting treatment efficacy. Part 2: Role of Spreading Depression in Ischemic Stroke Stroke is a prevalent disease that ranks as the 3rd leading cause of death and disability in the United States, according to NIH statistics, costing millions of dollars in medical costs and lost wages. At present, the mechanism by which focal ischemia evolves into infarction remains poorly understood. By determining the patho-physiological mechanisms involved in the evolution of focal brain ischemia, therapeutic strategies may be designed for instances of acute ischemic stroke. In the late 1980s, researchers discovered MRI techniques that allow the detection of stroke very early after onset. Such techniques as diffusion-weighted imaging and perfusion-weighted imaging (DWI and PWI) have been applied both clinically and experimentally. Previous studies employing these techniques suggest that cortical spreading depression plays a detrimental role in the evolution of focal brain ischemia. Spreading depression (SD) is characterized by a spontaneous and reversible depression of cortical electrical activity that spreads from the site of onset as a wave with a speed of 2-5 mm/min. It is accompanied by an ionic redistribution, with efflux of potassium ions (K+) and influx of sodium, chloride, and calcium (Na+, Cl-, Ca2+) ions, as well as water. This results in cellular swelling and a decreased extracellular space (ES), yielding a decline in ADC. A positive correlation between the number of both spontaneous and induced SDs and infarct volume has well been documented, supporting the idea that SD inhibition might be neuroprotective if initiated early after ischemic onset. Even though these studies show promise in their ability to track SD using diffusion mapping, changes in ADCs reflect cytotoxic edema and do not necessarily correspond to SD or SD-like depolarizations or calcium (Ca2+) influx, leading to cell death. Recent studies have reported the use of manganese ions (Mn2+) as a depolarization-dependent contrast agent in monitoring brain activation through the application of glutamate, as well as in the study focal ischemia. Since extracellular accumulation of potassium (K+) ions or glutamate in ischemic tissue is believed to play a central role in the initiation and propagation of SDs, and knowing that Mn2+, having an ionic radius similar to that of Ca2+, is handled in a manner similar to Ca2+, these studies suggest the possible use of manganese ions (Mn2+) in tracking SD or SD-like depolarizations in the evolution of focal brain ischemia. In order to determine the utility of Mn2+ as a marker for SD, two sets of T1-weighted MRI experiments were performed before applying Mn2+ in an experimental stroke model (Chapter 6). First, for verification purposes, a glutamate administration group was evaluated to validate our use of the manganese-enhanced MRI (MEMRI) method previously developed by Aoki et al, a modification of the original by Lin and Koretsky. When satisfied that the contrast enhancement was specific to glutamate only, a second set of experiments was performed. Here, experimental SD was elicited by chemical stimulation (direct application of concentrated potassium chloride [KC1] on the exposed cortical surface) and compared with control conditions (perfusion of sodium chloride [NaC1] on exposed brain cortex). This study demonstrated: (1) Mn2+, specific to Ca2+ channel activity, is a more accurate marker for SD than DWI or T2 methods; (2) Cortical restriction of MEMRI enhancement supports the contention that apical dendrites are necessary for SD propagation; (3) Subcortical enhancement is a result of corticalsubcortical neuronal connectivity; and (4) Because of the relatively slow clearance of Mn2+, MEMRI permits higher spatial resolution and signal-to-noise ratios (SNRs) via increased signal averaging. Based on these results, preliminary experiments involving the study of SD in focal ischemia using Mn2+ were performed (Chapter 7). Initial results indicate: (1) MEMRI of ischemia, when compared with standard DWI/PWI methods, may provide a method for estimating the likelihood of progression to infarct at acute time points post onset of stroke. These studies provide a foundation for further investigation into the role of SD in stroke, and the application of Mn2+ towards the design of therapeutic strategies targeting SD inhibition. Conclusions and Medical Significance The research within this dissertation employed magnetic resonance imaging techniques for monitoring the temporal evolution of pathological disease states such as focal ischemia and cancer, with and without therapeutic intervention. Optimization of these techniques in experimental models will open the possibility for future application in a clinical setting. Clinical availability of these non-invasive methods, with the ability to detect an early therapeutic response or to provide staging and prediction of tissue fate, would greatly aid in patient management of both cancer and stroke.

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Ice hockey, one of the most popular sports in the world, is a contact sport that is always associated with huge risks of traumatic brain injuries (TBIs) resulting from high-velocity impacts. Although technology in player protection equipment has advanced over the years, mild traumatic brain injuries (mTBIs) like concussion remain prevalent. Finite Element (FE) analysis presents a methodology to recreate accidents in an effort to study the effects of protective helmets and predict brain injuries. This study aimed at improving the response of an existing ice hockey helmet FE model during different impact conditions and reconstructing an ice hockey collision using FE simulations. First, the shear response of the Expanded Polypropylene (EPP) material for the helmet liner was improved by means of a single element simulation to replicate the experiments. Simulations of helmet drop tests were then performed to validate the helmet FE model. Two different designs of the helmet model were implemented, one with normal properties of the foam and the other with a softer foam. Actual cases of ice hockey accidents were then reconstructed using positioning and impact velocities as input from video analysis. As player to player collisions had not been reconstructed for ice hockey using two player models, it was decided to use two full body Human Body Models (HBMs) for the reconstruction. The biomechanical injury parameters for the accident reconstruction were plotted and compared with injury thresholds for concussion. The kinematic results achieved from the drop test simulations showed a considerable decrease in peak values for resultant accelerations, resultant rotational accelerations, and resultant rotational velocities. These results also exhibited better CORrelation and Analysis (CORA) scores than previously achieved. The biomechanical analysis of the accident reconstruction showed the strains in the brain for the concussed player to be more than the threshold for concussion, which confirms the validity of the reconstruction approach. The results of this study show an improved response of the helmet FE model under different impact conditions. They also present a methodology for ice hockey accident reconstruction using two full body HBMs.

Handen har en väldigt stor betydelse i människans liv. Med handen utför vi många olika slags viktiga sysslor. Vi äter, duschar och klär på oss med hjälp av handen. Vi skriver, sportar och utför arbete med handen. Vi hälsar på andra och kramar de som står oss nära med hjälp av handen. Syftet med denna studie är att undersöka vilka konsekvenser en handskada har i en persons liv. Metoden är en litteraturstudie av vetenskapliga artiklar som berör ämnet. Resultatet visar att smärta är den vanligaste konsekvensen efter en handskada. Fysiska begränsningar i vardagen såsom påverkan på aktiviteter i dagligt liv (ADL), hobby och hushållsarbete var ytterligare konsekvenser för en person efter en handskada. Resultatet visar också att psykiska påfrestningar, begränsningar inom arbetsliv och begränsningar i relation med andra i omgivningen är ytterligare problem som kan drabba handskadade. / The hand has a very large importance in the lives of humans. We perform many kinds of doings with the hand. We eat, shower and get dressed with help of the hand. We write, perform sports and work with the hand. We greet others and embrace the people who are close to us with help of the hand. The aim of this study is to investigate which consequences a hand injury has on a person’s life. The method is a literature study of scientific articles concerning the subject. The result reveals that pain is the most common consequence after a hand injury. Physical limitations in everyday life such as effect of activities in daily life (ADL), hobbies and household work were further consequences for a person with a hand injury. The result also shows that psychological strains and limits within work and in relation with others are further problems that can affect a person with a hand injury.

<p>Composite materials used in the aviation industry are known to be more complex than their metallic predecessors. This impacts not only the design and manufacturing of composite structures, but also the failure studies when these structures fail and break (as may be the case in an aircraft accident). Additionally, when under combustion, composite materials introduce potential health hazards. At elevated temperatures, the fibers can be released, presenting an inhalation hazard. Similarly, the matrix decomposition results in a series of potentially toxic byproducts. When encountering composite fires at aircraft accident sites, a series of protocols have been delineated by the corresponding agencies. These include wearing personal protective equipment as well as the application of so-called fixant solutions over the burning composites, with the latter being the focus of this study. The purpose of the fixant solutions is to provide a film of protection that – in essence – holds down small fibers and prevents them from becoming airborne. While the use of fixant solutions is necessary to protect the health of individuals in the vicinity of burnt composites, the potential detrimental impact the application thereof has on fractographic evidence should also be considered. Experts in the field have voiced concerns regarding the use of fixants, outlining that these chemicals may wash evidence away, cover up evidence, or interfere with imaging methods needed during the failure analysis. The purpose of the conducted research, thus, was to compare the relative impact of four commonly used fixant solutions – namely water, wetted water, polyacrylic acid (PAA), as well as a mixture of water and floor wax – on fractographic features of failed carbon fiber/epoxy composite specimens. Specifically, fractographic evidence of two forms of damage – impact and tension – were evaluated. With this goal, the methodology included steps to manufacture the specimens of interest, introduce the two forms of damage, burn the specimens, apply fixants, and perform the microscopic analysis via a scanning electron microscope (SEM). The fractographic evidence prior and after the application of fixant was evaluated qualitatively and quantitatively. The results showed that the evaluated fixants did influence the fracture surfaces imaged, and in certain cased obscured evidence of interest. Additionally, differences between the fixants were ascertained for both forms of damage evaluated. The water treatment was found to perform the best, minimizing the disruption of evidence. Nonetheless, while the study did answer the research questions and the different treatments were compared, additional areas of research and factors that should be considered were identified. </p>