196 research outputs found
The impact of blood component transfusion practices on patient survival after abdominal aortic aneurysm surgery
No full textBackground: The aim of the present study was to investigate the blood transfusion practice in patients operated for abdominal aortic aneurysm (AAA) with special emphasis on massive transfusion in cases with rupture. Material and methods: From a database, 504 patients operated for AAA were stratified into 2 groups; an early transfusion period (1992-1999) and a late transfusion period (2000-2008) to evaluate the changes in transfusion practices over the course of time. Results: Patients operated for nonruptured AAA (n = 330) showed a decreased mortality rate from 4% (early transfusion period) to 1% (late transfusion period) without significant changes in the transfusion practices. In patients operated for ruptured AAA (n = 174) an unexpected low mortality rate was found compared to the 30-day mortality reported in earlier studies. The transfusion practices in ruptured AAA surgery showed a significant increase in platelet use and change of fresh frozen plasma: red blood cell ratio from 0.8 to 0.9 between the early and the late transfusion period. Conclusion: The present database study shows that the operating mortality for AAA surgery has declined during the past decades. The cause of the decline in mortality in patients with ruptured AAA was interpreted as partly due to a modern blood component therapy. © The Author(s) 2012.Correspondence Address: Henriksson, A.E.; Laboratory Medicine, Sundsvall County Hospital, SE-851 86 Sundsvall, Sweden; email: [email protected]</p
What is the correlation between saliva levels of dexamphetamine
No full textABSTRACT
Degree Project, Programme in Medicine 2017. Author: Sofia Henriksson. Institution:
Pharmacology, Pharmacy & Anaesthesiology Unit, University of Western Australia, Perth.
Title: “What is the correlation between saliva levels of dexamphetamine and performance
on visual and auditory-visual illusions?”
Background: Schizophrenia is a psychiatric disorder associated with dopamine (DA)
hyperactivity. Given that dexamphetamine (DEX) elevates levels of DA in the brain, DEX
challenges can be used to model schizophrenia in research. Hallucinations and delusions are
two characteristic symptoms of schizophrenia and psychosis. Previous research suggests a
widened temporal binding window in which sensory stimuli can bind to form one perception
as a mechanism of how DA gives rise to hallucinations and delusions. Using illusion tests,
sensory stimuli can be manipulated and perception measured in an objective manner. Looking
into temporal and spatial windows in the visual-visual and visual-auditory sensory modalities,
26 healthy participants tested the Three Flash Illusion test (3-FI), Sound Induced Flash
Illusion test (SIFI), Visually Induced Flash Illusion test (VIFI), Phantom Word Illusion (PWI)
and McGurk effect on one day given DEX and one day given placebo. Aims: To determine
levels of DEX in saliva samples taken during the testing days and correlate those levels
closest in time to the illusion tests with performance on illusion test. Methods: Liquid-liquid
extraction and high performance liquid chromatography was used to determine the levels of
DEX in saliva. Raw data was analysed primarily with principal components analysis. Results:
For those significant differences in performance on illusion tests between DEX and placebo
days, levels of DEX in saliva correlated positively only with performance on VIFI and PWI
tests and not in the McGurk illusion. Conclusions: DEX-levels in saliva showed in our study
to be an unreliable predictor of performance on the illusion tests. However, more studies with
greater sample sizes are necessary to draw any final conclusions
Congestion Relief: Assessing the Case for Road Tolls in Canada
No full textExperience with road pricing generally — and congestion pricing specifically — is growing around the world. Research and planning in Canada should begin now on road pricing for heavily congested highways and streets.road pricing, traffic congestion
Sekundärprevention efter akut koronart syndrom : trombocythämmande behandling och riskfaktorkontroll
No full textBackground: One of the leading causes of death and disability worldwide is cardiovascular disease (CVD), including acute myocardial infarction (AMI). Despite improvements in medical treatment, management, and care over the years and the halving of mortality in recent decades, there is considerable room for improvement. Following myocardial infarction (MI), a patient is at great risk for subsequent infarctions or other related complications. In addition, the risk of ischemic stroke is increased following MI. Secondary prevention after MI is paramount for reducing further complications and consists of lifestyle changes, optimised medical treatment, and risk factor control of blood pressure (BP) and blood lipid levels. Although secondary preventive measures are effective, the proportion of patients reaching set treatment target levels is disappointingly low. Most patients are prescribed dual antiplatelet therapy (DAPT) following MI as part of their secondary preventive treatment. Several articles have been published on treatment efficacy based on comparisons with different kinds of antiplatelet drugs and in different combinations. However, little data specifically address the incidence of ischemic stroke after MI in real-world populations. In addition to antiplatelet treatment, secondary prevention comprises risk factor control of hypertension and hyperlipidaemia. Given the low proportion of patients reaching set target levels for BP and blood lipids, new strategies are needed. Aims: The aim of this dissertation is partly to elucidate if the rapid change in preferred DAPT in Sweden, from clopidogrel to ticagrelor in addition to aspirin, affected the incidence of ischemic stroke in patients suffering AMI (paper I) and in patients suffering AMI who have a history of ischemic stroke (paper II). The second part of the dissertation aims to investigate the feasibility and implementation of a randomised controlled trial of a nurse-led telephone-based secondary preventive program, and to assess the proportion of patients who can be included in an unselected acute coronary syndrome (ACS) population (paper III). Furthermore, the aim of the trial was to assess the long term results regarding systolic BP (SBP), diastolic BP (DBP), and low-density lipoprotein cholesterol (LDL-C) after 36 months of intervention and follow-up compared to a control group receiving usual care (paper IV). Methods: Papers I and II examined the impact of a change in the antiplatelet regimen following MI in regard to ischemic stroke occurrence. Data were obtained from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions (i.e., RIKS-HIA). The register was combined with the National Patient Register (NPR) and the Cause of Death Register (CDR) in order to obtain data on stroke occurrence. Patients with AMI and treated with either clopidogrel or ticagrelor were assigned to one of two cohorts, each covering a 2- year time period, with the initial prescription of ticagrelor (20 Dec 2011) used as a cutoff point. Patients in the early cohort (n=23,447) were treated exclusively with clopidogrel, whereas those in the later cohort (n=24,227) were treated with either clopidogrel (47.9%) or ticagrelor (52.1%). In paper II, the same methodology was used, but with a study sample restricted to AMI patients with a history of ischemic stroke. In paper II, there were 1633 patients in the early cohort and 1642 in the late cohort. In the late cohort, 66.3% patients were treated with clopidogrel and 33.7% with ticagrelor. Kaplan–Meier analysis was used to assess the risk of ischemic stroke over time, with multivariable Cox regression analysis used to identify predictors of ischemic stroke. Nurse-based Age independent Intervention to Limit Evolution of Disease (Papers III and IV were based on the NAILED)-ACS trial. The NAILED-ACS trial was an open randomised controlled trial of whether a nurse-led telephone-based follow-up and medical titration after MI or unstable angina achieved lower levels of BP and LDL-C than usual care. In paper III, patients admitted for ACS during January 2010 and December 2013 were evaluated for participation. Factors predicting participation and non- participation were assessed using logistic regression. Mortality rates after one year among included and excluded patients and patients declining participation were assessed using Kaplan–Meier analysis. For paper IV, all patients admitted with ACS at Östersund Hospital between January 2010 and December 2014 were screened for inclusion based on their ability to participate in a telephone- based follow-up. Participants were randomised into two parallel groups, an intervention group and a control group receiving usual care. BP and LDL-C were measured at 1, 12, 24, and 36 months. The baseline consisted of randomised patients who completed the one-month follow-up. The intervention group received counselling and medical titration to attain treatment targets (BP <140/<90 mmHg and LDL-C <2.5/<1.8 mmol/L). Adjusted means stratified by sex and type of ACS were calculated for SBP and DBP and LDL-C. The proportion of patients who achieved treatment target levels at the end of the study was also assessed. Results: Among the general AMI population treated with either clopidogrel or ticagrelor, the incidence of ischemic stroke after one year was 2.8% in the early cohort vs. 2.4% in the late cohort (p=0.001) (paper I). The study population in paper II, in which all patients had a history of previous ischemic stroke, was overall older and had a higher prevalence of comorbidities than the population in paper I. In paper II, incidence of ischemic stroke in the early cohort was 12.1% vs. 8.6% in the late cohort (p<0.01). Corresponding incidence of intracranial bleeding for the population in paper II was a non-significant 1.2% vs 1.5%. In the feasibility study of the NAILED-ACS trial (paper III), 907 patients were assessed for inclusion. Among these, 72.9% could be included (n=661), 146 patients (16.1%) were excluded, and 100 patients declined participation (11 %). Reasons for exclusion were mainly participation in another trial, dementia, inability to use a telephone, and advanced disease. Examples of predictors of both exclusion and declining participation were older age, lower functional status, and lower education. Non-participating patients had significantly higher mortality rates at one year compared to participating patients. Paper IV presents the final results of the NAILED-ACS risk factor trial in which a total of 962 patients were randomised and completed the one-month follow- up. Of this group, 797 were available for analysis after 36 months. Compared to the control group, in the intervention group, mean SBP was 4.1 mmHg lower, mean DBP was 2.9 mmHg lower, and mean LDL-C was 0.28 mmol/L lower (p<0.001 for all). The proportions of patients reaching treatment target goals for SBP, DBP, and LDL-C were significantly higher in the intervention group. In regard to SBP, 77.6% of intervention patients achieved treatment target levels, compared to 62.9% in the control group. Corresponding numbers for DBP were 90.9% vs. 80.8% and for LDL-C, they were 65.6% vs. 53.1% Conclusion: The incidence of ischemic stroke was significantly lower in a cohort of AMI patients following a change in preferred treatment from clopidogrel to ticagrelor (paper I). In AMI patients with a history of ischemic stroke (paper II), the incidence rate of ischemic stroke was significantly lower in the late cohort compared to the early cohort, and overall incidence rates were markedly higher than in paper I. The NAILED-ACS trial was shown to be both feasible (paper III) and successful, with a higher proportion of patients reaching treatment target levels in the intervention group, and significantly lower mean values for SBP, DBP, and LDL- C (paper IV)
Crisis communication; complex or simple : A study of four organizations’ crisis communication on Facebook
No full textSyftet med undersökningen är att få en bättre förståelse för hur fyra organisationerskriskommunikation kan se ut med dagens kommunikationsteknologi. Kommunikationsteknologidefineras i undersökningen som sociala medier, mer specifikt Facebook. För att uppnåundersökningens syfte har fyra organisationers Facebook feed under pågående kriser undersöktgenom att analyser hur de väljer att hantera information både från sig själva och från sinaintressenter. De fyra organisationer som har undersökts är Karlstad kommun, Halmstad kommun,SJ AB och Värmlandstrafik. Två frågor har ställts för att uppnå syftet:1. Hur arbetar dessa fyra organisationer med sin kriskommunikation på Facebook?2. Finns det skillnader och likheter mellan organisationernas sätt att hantera sin kriskommunikation?Det teoretiska ramverket för undersökningen presenterar tidigare forskning inom ämnet, teorier ochbegrepp inom litteraturen. Teorier som har använts för uppsatsen inkluderar situational crisiscommunication theory, en teori som baserar sig på att organisationer använder sig av kategoriseringav kriser för att välja en respons på en kris; komplexitetsteorin, som bygger på antagandet att varjekris är unik och därmed måste hanteras som sådan samt även command and control-principen ochAction-Nets som är teorier om hur organisationer använder sig av sociala nätverk och dessintressenter för att hantera information under en kris.Metoderna som har används för undersökningen är dels en kvantitativ innehållsanalys av de fyraorganisationernas Facebook feed under en kris, under tidsramen 2009-01-01 till 2012-12-24.Dessutom gjordes en kvantitativ innehållsanalys av specifika meddelanden under dessa perioder frånvarje organisation.Resultatet visar att Karlstad kommun, Halmstad kommun, SJ AB, men inte Värmlandstrafikanvänder sig av både situational crisis communication theory och komplexitetsteorin i sinakrisrelaterade meddelanden. Resultatet visade också på att organisationerna använder sig av den mertraditionella kriskommunikationen command and control-principen, i och med att de följde enmilitärisk hantering av informationsflödet. Undersökningen visar att flera av organisationernaanvänder sig av situational crisis communications theory. Undersökningen visar dessutom attorganisationerna använder sig av komplexitetsteorin.The purpose of this essay have been to gain a better understanding of how four different organizations utilize today’s communication technology in their crisis communication. Today’s communication technology referrers to social medias, more specifically Facebook. To complete the purpose of this essay, the four organizations crisis communication has been studied during a crisis and how they chose to handle the flow of information during a crisis. The four organizations that have been picked for the essay is the municipality of Karlstad, the municipality of Halmstad, SJ AB and Värmlandstrafik. These organizations uses Facebook in their crisis communication and the essay have thereby used that information in the study. Two questions were asked to help the essay reach its purpose:1. How do these four organizations work with their crisis communication on Facebook?2. Is there any similarities or differences between these organizations and how they communicate during a crisis?The theoretical framework for the essay presents early studies within the subject, different theories and concepts within crisis communication. Theories that have been used are situational crisis communication theory, a theory that builds around the concept of categorizing crises and choosing a proper response to the crisis. Complexity theory, which builds around the concept that every crisis is unique and therefore cannot be handled in the same way as a previous crisis. Command and control, as well as Action-nets, which is a theory about how organizations use social medias to communicate during a crisis.The methods used for the essay have been a quantitative content analysis of the four different organizations Facebook feed during a crisis, between 2009-01-01 and 2012-12-24. A qualitative content analysis was also conducted on parts of the data gathered from the quantitative analysis.The results from both analysis showed that the municipality of Karlstad, the municipality of Halmstad and SJ AB all used both situational crisis communication theory and complexity theory in their crisis related messages. At the same time it also showed that Värmlandstrafik is lacking within crisis communications. It also showed that all organizations still used a more traditional crisis communication, command and control, in the way they used the flow of information during a crisis. In conclusion: The studies have given a better understandin
Prevalence of ideal cardiovascular health in European adolescents: The HELENA Study
No full textThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Background: The ideal cardiovascular health (iCVH) construct consists of 4 health behaviours and 3 health factors and is strongly related to later cardiovascular disease. However, the prevalence of iCVH in European adolescents is currently unknown.
Methods:
The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study is a cross-sectional, multicentre study conducted in 9 European countries during 2006-2007 and included 3528 adolescents (1683 boys and 1845 girls) between 12.5 and 17.5 years of age. Status (ideal vs. non-ideal) for the health behaviours (smoking status, body mass index, physical activity and diet) and health factors (total cholesterol, blood pressure and fasting glucose) were determined.
Results:
Overall, the prevalence of ideal health behaviours was low; non-smoking (60.9% ideal), body mass index (76.8%), physical activity (62.1%), and diet (1.7%). The prevalence of ideal health factors was; total cholesterol (65.8%), blood pressure (62.0%) and plasma glucose (88.8%).
Conclusions:
The low prevalence of iCVH behaviours, especially diet and physical activity, identified in European adolescents is likely to influence later cardiovascular health which strongly motivates efforts to increase ideal health behaviours in this population.The HELENA project was supported by the European Community Sixth RTD Framework Programme (contract FOOD-CT-2005-007034). The data for this study was gathered under the aegis of the HELENA project, and further analysis was additionally supported by the Spanish Ministry of Economy and Competitiveness (grants RYC-2010-05957 and RYC-2011-09011), the Spanish Ministry of Health: Maternal, Child Health and Development Network (grant RD16/0022), the Fondo Europeo de Desarrollo Regional (MICINN-FEDER) and by the University of Granada, Plan Propio de Investigación 2016, Excellence actions: Units of Excellence; Unit of Excellence on Exercise and Health (UCEES). Pontus Henriksson was supported by a grant from Henning and Johan Throne-Holst Foundation. Hanna Henriksson was supported by grants from the Swedish Society of Medicine and the County Council of Östergötland, Sweden
Transitioning into a discipline – exemplars as cognitive resources in learning physics
No full textWhich classical experiments, derivations or labs must a physicist – or a high-school graduate – know and be able to reproduce? From a disciplinary perspective, this set of activities were identified by Kuhn (1970, 1977) as the exemplars of a scientific community – “concrete problem solutions, accepted by the group as, in quite a usual way, paradigmatic” (Kuhn 1977, p. 299). At the level of high-school science education, this could for instance be Galileo’s dropping of spheres with different masses from the Leaning Tower of Pisa, or the combustion of steel wool to demonstrate oxidation. In this presentation, we argue that it will be fruitful to consider exemplars also on an individual basis, as particular instances of compiled knowledge structures. Knowledge structures and cognitive resources have been described on an individual level both more widely (Nosofsky, 2002; Smith, 2014) and within Physics Education Research (PER) (e.g. Harrer, 2019; Goodhew et al., 2018). Given the central role of exemplars on the disciplinary level, the individual student who enters the discipline must acquire a wide range of exemplars as part of their own knowledge structure. To investigate this learning process, and ultimately to facilitate and enhance it, we propose to study exemplars from a disciplinary cognitive framework such as the Resources framework by Hammer (2000) and Redish (2004, 2014). The Resources framework informs us that students carry a diverse set of cognitive resources that may lead to either productive or unproductive reasoning depending on the context and the knowledge structure from which they are activated, i.e. the sociocultural and cognitive level (Redish, 2004). Effective learning activities should activate an appropriate set of resources – for instance p-prims (diSessa 1993), every-day experiences or previous exemplars – that can form the basis of a new productive knowledge structure. This viewpoint contrasts previous research that focused on changing established misconceptions (e.g. Posner et al., 1982; Johnstone et al., 1977), something which has been proven quite difficult to achieve (Dunbar et al, 2007). It may instead be more effective to focus on generating and strengthen new productive cognitive resources, and in particular exemplars given their important position within the discipline
Transitioning into a discipline – exemplars as cognitive resources in learning physics [Elektronisk resurs]
No full textWhich classical experiments, derivations or labs must a physicist – or a high-school graduate – know and be able to reproduce? From a disciplinary perspective, this set of activities were identified by Kuhn (1970, 1977) as the exemplars of a scientific community – “concrete problem solutions, accepted by the group as, in quite a usual way, paradigmatic” (Kuhn 1977, p. 299). At the level of high-school science education, this could for instance be Galileo’s dropping of spheres with different masses from the Leaning Tower of Pisa, or the combustion of steel wool to demonstrate oxidation.In this presentation, we argue that it will be fruitful to consider exemplars also on an individual basis, as particular instances of compiled knowledge structures. Knowledge structures and cognitive resources have been described on an individual level both more widely (Nosofsky, 2002; Smith, 2014) and within Physics Education Research (PER) (e.g. Harrer, 2019; Goodhew et al., 2018). Given the central role of exemplars on the disciplinary level, the individual student who enters the discipline must acquire a wide range of exemplars as part of their own knowledge structure. To investigate this learning process, and ultimately to facilitate and enhance it, we propose to study exemplars from a disciplinary cognitive framework such as the Resources framework by Hammer (2000) and Redish (2004, 2014). The Resources framework informs us that students carry a diverse set of cognitive resources that may lead to either productive or unproductive reasoning depending on the context and the knowledge structure from which they are activated, i.e. the sociocultural and cognitive level (Redish, 2004). Effective learning activities should activate an appropriate set of resources – for instance p-prims (diSessa 1993), every-day experiences or previous exemplars – that can form the basis of a new productive knowledge structure. This viewpoint contrasts previous research that focused on changing established misconceptions (e.g. Posner et al., 1982; Johnstone et al., 1977), something which has been proven quite difficult to achieve (Dunbar et al, 2007). It may instead be more effective to focus on generating and strengthen new productive cognitive resources, and in particular exemplars given their important position within the discipline.</p
Thales of Miletus, Archimedes and the Solar Eclipses on the Antikythera Mechanism
No full textThales of Miletus (640?-546 BC) is famous for his prediction of the total solar eclipse in 585 BC. In this paper, the author demonstrate how Thales may have used the same principle for prediction of solar eclipses as that used on the Antikythera Mechanism. At the SEAC conference in Alexandria in 2009, the author presented the paper “Ten solar eclipses show that the Antikythera Mechanism was constructed for use on Sicily.” The best defined series of exeligmos cycles started in 243 BC during the lifetime of Archimedes (287-212 BC) from Syracuse. The inscriptions on the Antikythera Mechanism were made in 100-150 BC and the last useful exeligmos started in 134 BC. The theory for the motion of the moon was from Hipparchus (ca 190-125 BC). A more complete investigation of the solar eclipses on the Antikythera Mechanism reveals that the first month in the first saros cycle started with the first new moon after the winter solstice in 542 BC. Four solar eclipses 537-528 BC, from the first saros cycle, and three one exeligmos cycle later, 487-478 BC, are preserved and may have been recorded in Croton by Pythagoras (ca 575-495 BC) and his school
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