60 research outputs found

    The assessment of disease progression in keratoconus and corneal crosslinking in thin corneae

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    Keratoconus generally manifests in adolescents, and can progress leading to severely impaired vision. The risk of progression is inversely correlated to age; thus younger patients are at higher risk than older ones. Progressive keratoconus can be halted by corneal crosslinking (CXL). The general indication for CXL is progressive keratoconus, although children are commonly treated with CXL upon diagnosis. Tomography is used to assess progression, and the most commonly used system is the Pentacam HR. Measurements made on different visits are compared to determine whether the patient’s keratoconus has progressed, and they should be referred for CXL. However, there is no consensus on which parameters should be used, or the change in magnitude of these parameters that indicates progression. An increase in the curvature power of the steepest point on the anterior surface, Kmax, of 1.0 dioptres is commonly used for all patients. However, there is little evidence that this is appropriate. Furthermore, inconsistent results have been presented regarding the magnitude at which progression can be detected. Such studies are often based on determinations of the repeatability of measurements made on one occasion. However, the progression of keratoconus is evaluated from measurements made on different occasions, and it is reasonable to assume that measurements obtained on different days will be subject to greater variation due to the biomechanical instability of corneae affected by keratoconus. Also, it has been suggested in studies that the repeatability of measurements in subjects with more severe keratoconus have poorer repeatability. Another important aspect of keratoconus is that it is a thinning disorder. A minimum corneal thickness of 400 µm has been suggested for the safe performance of CXL. Thus, a significant proportion of keratoconus patients will be excluded from the standard CXL treatment protocol.Thus, in the first study we elucidated the association between measurement error and disease severity. In the second investigation we investigated the inter-day repeatability and in the third investigation we investigated the Belin ABCD Progression Display. In the fourth study we investigate a protocol in which sterile water was added during the crosslinking procedure to increase the corneal thickness. The results demonstrated that the measurement error is associated to the disease severity and that limits at which progression is defined should be defined by inter-day measurements. The results also suggest that the diagnosis of progressive keratoconus by the Belin ABCD Progression Display will lead to overdiagnosis of progression. Further, the results suggest that the addition of sterile water is effective in increasing the corneal thickness above the suggested safety limits. These results have important clinical implications. The results demonstrate that limits at which progression is defined should be stratified according to the severity of the disease. Patients with less advanced keratoconus will be underdiagnosed as progressive if commonly used parameters are not stratified according to disease severity. This could lead to delayed referral for CXL, resulting in an avoidable risk of deterioration in vision. Patients with more advanced keratoconus, on the other hand, would be overdiagnosed as progressive, which could lead to unnecessary CXL, thus subjecting the patient to discomfort and possible treatment-associated complications. This risk of overdiagnosis of progression is also relevant when using the Belin ABCD Progression Display. Further, The data suggest that such a simple measure as adding sterile water during corneal crosslinking could enhance the corneal thickness above safety limits

    Icebound frontiers of exploitation:Networks for whaling in the Polar regions, 1904-1931

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    Work ethics and general work attitudes in adolescents are related to quality of life, sense of coherence and subjective health – a Swedish questionnaire study

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    BACKGROUND: Working life is an important arena in most people's lives, and the working line concept is important for the development of welfare in a society. For young people, the period before permanent establishment in working life has become longer during the last two decades. Knowledge about attitudes towards work can help us to understand young people's transition to the labour market. Adolescents are the future workforce, so it seems especially important to notice their attitudes towards work, including attitudes towards the welfare system. The aim of this study was to describe and analyse upper secondary school students' work attitudes, and to explore factors related to these attitudes. METHODS: The sample consisted of 606 upper secondary school students. They all received a questionnaire including questions about quality of life (QOL), sense of coherence (SOC), subjective health and attitudes towards work. The response rate was 91%. A factor analysis established two dimensions of work attitudes. Multivariate analyses were carried out by means of logistic regression models. RESULTS: Work ethics (WE) and general work attitudes (GWA) were found to be two separate dimensions of attitudes towards work. Concerning WE the picture was similar regardless of gender or study programme. Males in theoretical programmes appeared to have more unfavourable GWA than others. Multivariate analyses revealed that good QOL, high SOC and good health were significantly related to positive WE, and high SOC was positively related to GWA. Being female was positively connected to WE and GWA, while studying on a practical programme was positively related to GWA only. Among those who received good parental support, GWA seemed more favourable. CONCLUSION: Assuming that attitudes towards work are important to the working line concept, this study points out positive factors of importance for the future welfare of the society. Individual factors such as female gender, good QOL, high SOC and good health as well as support from both parents, positive experience of school and work contacts related positively to attitudes towards work. Further planning and supportive work have to take these factors into account

    Icebound frontiers of exploitation: Networks for whaling in the Polar regions, 1904-1931

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    In my researchproject, I have studied the history of Natural resource exploitation in the polar regions. More specifically, I have studied the history of the modern whaling industry in both the Arctic and the antarctic. Previous research have mainly focused on, and explained modern whaling as just another Activity to make quick profit. In my research I show that it was more complex than this, and that scientific, economic, political, and environmental factors dictated and determined the activities of the modern whaling industry. This thesis is a part of the International Polar Year Project LASHIPA (Large Scale Historical Exploitation of Polar Areas), where researchers from the Netherlands, Sweden, Norway, USA and Russia have studied the history of exploitation in the polar regions. For more information please see the webpage of the Arctic Centre/Groningen Institute for Archaeology

    To Detect Relationship Violence – A Compilation of Six Screeners : A Literature Overview

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    Bakgrund Mäns våld mot kvinnor är ett globalt hälsoproblem, som spänner över såväl religiösa, geografiska som socioekonomiska gränser. En metod för att hitta dessa kvinnor är att administrera ett så kallat screeningverktyg eller frågeformulär. De tillgängliga verktygen är många och inget anses än vara vedertaget inom svensk hälso- och sjukvård. Syfte Att sammanställa en översikt av olika screeningverktyg som kan hjälpa sjuksköterskan att upptäcka mäns våld mot kvinnor. Metod Litteraturöversikt i form av en beskrivande sammanställning, baserad på tolv vetenskapliga artiklar av kvalitativ ansats. Resultat En sammanställning av sex screeninginstrument (ASI, HITS, PVS, STaT, WAST och WEB) presenteras. Frågeformulärens sensitivitet och specificitet redovisas, exempel på frågor samt styrkor och svagheter i formuläret beskrivs. Slutsats De sex beskrivna screeninginstrumenten har ett gemensamt syfte, att upptäcka våld. De skiljer sig åt i psykometriska egenskaper och är svåra att jämföra med varandra. En beskrivande översikt har utformats där läsaren själv kan bilda sig en uppfattning. Klinisk betydelse Översikten i denna uppsats skulle kunna hjälpa verksamheter i vården att lättare välja ut ett frågeformulär för våldsscreening som passar för just den verksamheten.Background Intimate partner violence is a global health issue concerning women, spanning across religious, geographic and socioeconomic boundaries. One way of finding these women is by administrating a screening tool, or questionnaire. There are many tools available but none of them are established in the Swedish healthcare system. Aim To compile an overview of different screening tools that can help the nurse to detect intimate partner violence. Method A literature overview in form of a descriptive compilation, based on twelve scientific articles of quantitative research. Result A presentation of six screening tools (ASI, HITS, PVS, STaT, WAST and WEB). The sensitivity, specificity and pros and cons of each questionnaire are described. Conclusion The six described screening instruments were all made to detect violence. They differ in psychometric properties and are difficult to compare. A descriptive overview has been designed where the reader himself can make an opinion. Clinical significance Intimate partner violence is a big health issue and it is of the out most concern that it is made public and that the women affected gets help. The screening tools presented may be the first step towards that

    Early findings in a prospective randomised study on three cross-linking treatment protocols: interruption of the iontophoresis treatment protocol

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    Purpose To present the outcome of the interrupted iontophoresis-assisted treatment arm in an ongoing randomised clinical trial (NCT04427956).Methods A randomised clinical study of corneal cross-linking (CXL) using continuous UV-A irradiation at a rate of 9 mW/cm2 and three different types of riboflavin and riboflavin delivery mode: (1) iso-osmolar dextran-based riboflavin (epithelium-off), (2) hypo-osmolar dextran-free riboflavin (epithelium-off) and (3) iontophoresis-assisted delivery of riboflavin (epithelium-on) for the treatment of progressive keratoconus. Inclusion criteria were an increase in the maximum keratometry value (Kmax) of 1.0 dioptre over 12 months or 0.5 dioptre over 6 months. The primary outcome in evaluating treatment efficacy was Kmax. Recently presented stratified detection limits were used post hoc to confirm the enrolment of patients with truly progressive keratoconus and in the assessment of the need for re-CXL.Results Thirteen patients had been randomised to iontophoresis-assisted CXL when the treatment arm was interrupted; two patients dropped out. Of the remaining 11 patients, 7 were deemed as having truly progressive disease according to the more recent stratified detection limits. The disease continued to progress in three patients according to the original definition (increase in Kmax≥1 D), necessitating re-CXL with epithelium-off CXL. This progression was confirmed by post hoc analysis using the stratified detection limits for progression.Conclusions The iontophoresis-assisted CXL protocol failed to halt further disease progression in 27% of the patients. The failure rate increased to 38% when considering only the patients deemed to have truly progressive disease using the stratified detection limits
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