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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

En utvärdering av 5-HT1A-receptoragonisten vilazodone för en utökad antidepressiv effekt i behandlingen av egentlig depression / Evaluation of the antidepressant effect of vilazodone for the treatment of major depression

Khalifa, Aseel January 2017 (has links)
Major depressive disorder (MDD) is a mood disorder majorly responsible for disability and mortality worldwide. With a lifetime prevalence of 15-20%, it is the main cause of functional impairment in Western societies as well as the fourth most debilitating illness in the world. Although the pathophysiology of MDD is not yet fully understood, some evidence that suggest the presence of a neuroanatomical deficiency have given rise to the theory of a specific imbalance in the monoamine neurotransmitters noradrenaline (NA) and/or serotonin (5-HT) levels in the brain. Overall, the various classes of antidepressant agents that have been developed to increase monoamine levels on the basis of this proposal have been successful. However, facts relating to prevalent escalation in the illness and recurring episodes of depression point towards a need to enhance clinical treatment. Most conventional antidepressants such as selective serotonin reuptake inhibitors (SSRI) and selective serotonin and noradrenaline inhibitors (SNRI) pose problems in symptomatic improvement. These include therapeutic lag, safety and tolerability issues, making more than 30% patients with MDD unable to reach adequate relief. In this respect, the action mechanism has moved beyond conventional SSRI and lead to the introduction of vilazodone, a novel antidepressant with an additional 5-HT1A partial agonist profile argued to be of potential benefit for a greater efficacy, faster onset of action and better tolerability. Using secondary data, this project aimed to evaluate the role of vilazodone as a SPARI-drug in the overall clinical treatment of MDD as well as its potential in addressing some of the most common obstacles in antidepressant treatment. Study results proved vilazodone’s efficacy to be superior to placebo. Patients across all studies showed significant improvement in depressive symptoms measured in MADRS and HAMD17. Vilazodone was also shown to be generally safe and tolerable but was not positively distinguished from placebo with regards to adverse effects. An overall, meaningful improvement in depressive symptoms was demonstrated in vilazodone, which reinforces its merit as an important treatment option for patients with MDD.
22

Effektivitet och säkerhet av tricykliska antidepressiva och selektiva serotonin-återupptagshämmare vid behandling av irritabel tarmsyndrom (IBS)

Muatasim, Mustafa January 2021 (has links)
Irritable bowel syndrome (IBS) is a functional disorder that affects the gastrointestinal tract and especially the large intestine. The pathogenesis of the disease is not fully understood, for that reason there is still no cure and current therapy focuses on symptom relief. The disease manifests itself in the form of abdominal pain, bloating, constipation or diarrhoea. New studies have shown a link between IBS and communication between the central nervous system and the gut. Serotonin and norepinephrine seem to be important for the course of the disease. The purpose of this literature review was to study the efficacy and safety of certain antidepressant preparations belonging to tricyclic antidepressants and selective serotonin reuptake inhibitors in the treatment of IBS. This work focused on the effect of preparations and how tolerable they are with respect to their side effects. Articles presented in this work were found in the PubMed database with the keywords "irritable bowel syndrome", "serotonin reuptake inhibitor", " tricyclic antidepressants ". Amitriptyline 10 mg and imipramine 25 mg provided a statistically significant symptom relief in IBS with diarrhoea (IBS-D) compared to placebo. In addition, tianeptine 12.5 mg 3 times / day, which belongs to the selective serotonin reuptake enhancer (SSRE) group, gave a corresponding symptom relief as amitriptyline 10 mg once / day. The difference between the two was not statistically significant, but the study was open label and non-placebo-controlled, which made it difficult to draw any conclusions. Fluoxetine, which belongs to the selective serotonin reuptake inhibitor (SSRI) group, produced a statistically significant effect compared to placebo in the treatment of constipation IBS (IBS-C). In contrast, paroxetine-CR did not have any statistically significant effect on abdominal pain in IBS-C compared with placebo. However, more patients in the paroxetine group achieved the secondary outcome (clinical global improvement) with scores of 1-2 on the scale Clinical Global Impressions-Improvement (CGI-I). Based on the studies presented in this literature study, it is concluded that a low dose of TCA is an effective and safe treatment for IBS-D while SSRIs are effective and safe in the treatment of IBS-C compared to placebo. / Irritable bowel syndrome (IBS), är funktionella störningar som drabbar gastrointestinalkanalen och framför allt kolon. Patogenesen till sjukdomen är inte helt klarlagd, av den anledningen saknas fortfarande någon botande behandling och dagens terapi fokuserar på symtomlindring. Sjukdomen yttrar sig i form av buksmärta, uppblåsthet, förstoppning eller diarré. Senaste studier har visat en koppling mellan IBS och kommunikation mellan centrala nervsystemet och tarmen. Serotonin och noradrenalin verkar ha betydelse för sjukdomsförlopp. Syftet med detta litteraturarbete var att studera effektivitet och säkerhet för några antidepressiva preparat som tillhör tricykliska antidepressiva och selektiva serotonin återupptagshämmare vid behandling av IBS. Detta arbete fokuserade på effekten av preparaten och hur tolererbara de är med avseende på deras biverkningar. Artiklar som presenteras i detta arbete söktes i databasen Pubmed med sökord ”irritable bowel syndrome”, ”serotonin reuptake inhibitors”, ” tricyclic antidepressants”. Amitriptylin 10mg och imipramin 25mg gav en statistiskt signifikant symtomlindring vid IBS med diarré (IBS-D) jämfört med placebo. Dessutom gav tianeptin 12,5mg 3 gånger/dag, som tillhör läkemedelsgruppen selektiv serotonin återupptagsenhancer (SSRE), en likvärdig symtomlindring som amitriptylin 10mg en gång/dag. Skillnaden mellan de två var inte statistiskt signifikant, däremot var studien openlabel och icke-placebokontrollerad vilket gör det svårt att dra någon slutsats. Fluoxetin, som tillhör läkemedelsgruppen selektiva serotonin återupptagshämmare SSRI, gav en statistiskt signifikant effekt jämfört med placebo vid behandling av IBS med förstoppning (IBS-C). Däremot gav paroxetin-CR ingen statistiskt signifikant effekt på buksmärta vid IBS-C jämfört med placebo, dock uppnådde fler i paroxetingruppen den sekundära utfallsvariabeln (global klinisk förbättring) och fick poäng mellan 1 – 2 på skalan Clinical Global Impressions-Improvement (CGI-I).  Baserat på studierna som presenteras i denna litteraturstudie dras slutsatsen att en låg dos TCA är en effektiv och säker behandling vid IBS-D medan SSRI är effektiva och säkra vid behandling av IBS-C jämfört med placebo.
23

Impacts of misbehavior in Intelligent Transportation Systems (ITS) : The case of cooperative maneuvers / Påverkan av felaktigt beteende i Intelligenta Transportsystem (ITS) : Fallet med kooperativa manövrar

Henriksson, Andreas January 2022 (has links)
Connected and autonomous vehicles are emerging technologies that have fostered the Intelligent Transportation System (ITS). ITS has the objective of optimizing traffic safety, mobility, and fuel consumption. To achieve this, a range of different services are provided that utilize communication in a vehicular network. One of these services that has received a lot of attention lately due to its ongoing standardization is the Maneuver Coordination Service (MCS). MCS has already shown great potential in the support of complex traffic areas, also called Transition Area (TA), where vehicles must cooperate to avoid Transition of Controls (ToCs). ITS-services often rely on communicated data; small errors, such as inaccessible or incorrect data, can cause the system to behave incorrectly. Signal interference (jamming) can cause communication interruptions, making vehicles unaware of each other. Incorrect data can be intentional due to data injection attacks, but also unintentional due to malfunctioning sensors, making vehicles incorrectly aware of each other. Incorrect behavior in systems such as ITS can lead to traffic congestion or even life-threatening collisions. This study focuses on MCS and examines traffic behavior when the service, in a generic traffic scenario, is subjected to jamming and falsification attacks with a variety of strategies (negative and positive speed, acceleration and position offset). We considered external attackers (not authenticated) that can disrupt communication, as well as internal attackers (authenticated) that are limited to tampering with outgoing data. Through severe collisions and travel time delays, the results show an impact on both safety and mobility. The results also show that different attacks with different impacts on the adversary can cause similar effects on the traffic, thus allowing the adversary to choose attacks based on the desired impact and its rationality, i.e. its willingness to be part of the impact. The study also proposes an extension to an already proposed Maneuver Coordination Protocol (MCP). We show that our extended MCP can be beneficial in avoiding dangerous maneuvers that could lead to collisions with cars in the blind spot. / Uppkopplade och autonoma fordon är framväxande teknologier som har främjat Intelligenta Transporteringssystem (ITS). ITS har som mål att optimera trafiksäkerhet, mobilitet och bränsleförbrukning. För att uppnå detta tillhandahålls en rad olika tjänster som utnyttjar kommunikation i ett fordonsnät. En av dessa tjänster som har fått mycket uppmärksamhet under den senaste tiden, tack vare sin pågående standardisering, är Manöverkoordinationtjänsten (MCS). MCS har redan visat stor potential för att stödja komplexa trafikområden, även kallade Övergångsområden (TA), där fordon måste samarbeta för att undvika kontrollövergångar (ToCs). ITS-tjänster förlitar sig ofta på kommunicerad data; små fel, som otillgängliga eller felaktiga data, kan göra att systemet beter sig felaktigt. Signalstörningar kan orsaka kommunikationsavbrott, vilket gör fordon omedvetna om varandra. Felaktig data kan vara avsiktliga på grund av datainjektionsattacker, men också oavsiktliga på grund av felaktiga sensorer, vilket gör fordon felaktigt medvetna om varandra. Felaktigt beteende i system som ITS kan leda till trafikstockningar eller till och med livshotande kollisioner. Denna studie fokuserar på MCS och undersöker trafikbeteendet när tjänsten, i ett generiskt trafikscenario, utsätts för signalstörningar och förfalskningsattacker med en mängd olika strategier (negativ och positiv hastighet, acceleration och positionsförskjutning). Vi tog hänsyn till externa angripare (ej autentiserade) som kan störa kommunikationen, såväl som interna angripare (autentiserade) som är begränsade till att manipulera utgående data. Genom allvarliga kollisioner och restidsförseningar visar resultaten en inverkan på både säkerhet och mobilitet. Resultaten visar också att olika attacker med olika inverkan på angriparen kan orsaka liknande effekter på trafiken, vilket gör att angriparen kan välja attacker baserat på den önskade effekten och rationaliteten, d.v.s. dens villighet att vara en del av påverkan. Studien föreslår också en utökning av en redan föreslagen MCP. Vi visar att vårt utökade MCP kan vara till nytta för att undvika farliga manövrar som kan leda till kollisioner med bilar i döda vinkeln.
24

Lärare sår ett frö inför framtiden : En intervjustudie med SO-lärare inom åk 4–6 med fokus på hur de undervisar för att främja hållbar utveckling / Teacher planting a seed for the future : An interview study with social science teachers in grades 4–6 with a focus on how they teach to promote sustainable development

Blixt, Beatrice, Nyyssönen, Mathilda January 2024 (has links)
Syftet med denna studie är att bidra med kunskap om vilka förmågor och kunskaper som grundskollärare inom SO-ämnena anser är viktiga att främja genom undervisning för hållbar utveckling, i år 4–6. Syftet är vidare att belysa hur de beskriver att deras undervisning skapar möjlighet för eleverna att utveckla dessa kunskaper och förmågor. Det ingår i skolans uppdrag att förmedla kunskap och respekt för vår gemensamma miljö. Forskning som berör hållbar utveckling och undervisning i skolan har historiskt sett främst genomförts med inriktning på förskolan, grundskolans senare år och gymnasiet. Inom årskurs 4–6 är forskningen begränsad, vilket är en anledning till att denna studie genomförts. De tre selektiva miljöundervisningstraditionerna; den faktabaserade, den normerande och den pluralistiska används som ett teoretiskt ramverk för denna studie. Genom en kvalitativ undersökning i form av semistrukturerade intervjuer av sju behöriga SO-lärare i årskurs 4–6 besvarade studiens tre forskningsfrågor. En tematisk analys genomfördes på det insamlade materialet och resulterade i tio teman som sorterades in under överrubriker. Resultatet visade att faktakunskaper, medvetenhet, framtidstro och en förhoppning om att så ett frö för framtiden är något som lärarna vill ett deras elever ska få med sig. Att utgå från samtal, diskussioner och temaarbeten var metoder som ansågs kunna möjliggöra att eleverna får med det som lärarna anser viktigt. Elevers värderingar, tidsbrist och anpassning av innehåll utifrån elevernas ålder ansågs försvåra undervisningen. Trots dessa svårigheter är detta ett ämne som engagerar många elever, vilket ses som en möjlighet i undervisning för hållbar utveckling. Slutligen konstateras att de slutsatser som dras i forskning för hållbar utveckling inte alltid verkar överensstämma med läroplanens innehåll vilket i förlängningen påverkar både undervisningen och vad eleverna får med sig från undervisning för hållbar utveckling. / The purpose of this study is to contribute knowledge about which abilities and knowledge social science teachers in primary school consider important to promote through teaching for sustainable development, in grades 4–6. The purpose is further to highlight how they describe that their teaching creates opportunities for students to develop these skills and abilities. One way to enable action is through education. It is also part of the school's mission to convey knowledge and respect for our common environment. Historically speaking, research concerning sustainable development and teaching in schools has mainly been focused on pre-school, the later years of compulsory school and upper secondary school. Within grades 4-6, research is limited and that is one reason that lies behind this study. The three selective environmental education traditions; the fact-based, the normative and the pluralistic were used as a theoretical framework for this study. Through a qualitative investigation in the form of semi-structured interviews of seven qualified social science teachers in grades 4-6 from four different municipalities, the study's three research questions were answered. A thematic analysis was carried out on the collected material and resulted in ten themes. The themes were sorted under three headings. The result showed that factual knowledge, awareness, faith in the future and a hope to plant a seed for the future are some things that the teachers want their students to develop. Conversations, discussions and theme work were methods considered to enable the students to develop what the teachers considered important. Pupils' values, lack of time and adaptation of content based on the pupils' age were considered challenges. Despite these challenges, sustainable development engages many students, which can be seen as an opportunity in teaching for sustainable development. Finally, it is stated that conclusions drawn in research for sustainable development do not always seem to correspond with the content of the curriculum. Which in the long run affects both how teachers chose to teach for sustainable development and what students learn from it.
25

Lärares beskrivningar av evolution som undervisningsinnehåll i biologi på gymnasiet

Petersson, Maria January 2012 (has links)
Biological evolution is part of the syllabi for Biology and Science in Swedish upper secondary school. In the syllabi, evolution is not only presented as a topic in Biology courses, but is also regarded as a unifying theme. The teacher has a fundamental role in deciding how the national curriculum is translated into the educational situation. This thesis investigates teachers’ accounts of their teaching of evolution in Swedish upper secondary school, describing their understandings of the purpose of teaching and learning evolution as part of biology education. The thesis is based on interviews of teachers teaching the course Biology A, which is compulsory as dictated by the Natural Science Program. The interviews were supplemented with questionnaires. The interviews were orientated towards questions about selection of course content and the reasons for choosing this content. The interviews were focused on teachers experiences based on their own practice. Two aspects of content were examined: (1) the scientific content taught in terms of themes and (2) the socializing value-laden aspects, such as priorities taken by the teachers and the teachers´ overarching aims.   The results showed that teachers described different teaching contents with regard to values, even when the core content of themes was similar. Four different selective traditions for choosing content were identified among teachers. The results are discussed in relation to the context and conditions that the teachers identify as influential on the content chosen. Teachers’ interactions with their students as well as their world views are important for their selection and adjustment of content. There are also indications that teachers’ personal views about purposes are important for selecting the teaching content.
26

Lärares syn på undervisning för hållbar utveckling och dess utmaningar / Teachers' views on education for sustainable development and its challenges

Silva, Joel, Lagerstedt, Elin January 2023 (has links)
Environmental concerns and climate change strengthens the need of education for sustainable development. We have both acknowledged a need of more research aimed towards teachers in Swedish primary schools. Therefore, the ambition for this study is to contribute with more knowledge about sustainable development in primary schools with an emphasis on science education. In this qualitative study we interview teachers working in pre-school class and primary school years 1-3 about what they think pupils should learn in education for sustainable development, as well as what their practical approaches are to the subject and what the didactical challenges are. We used semi-structured interviews to interview six teachers from three different schools in a Swedish city. The collected data is analyzed and presented using a thematic analysis and the research questions that are based on the aim for this study. The results of the study are then put in relation to our theoretical perspectives, which are “the three selective traditions in environmental and sustainability education” and “individual and collective responsibility”, to draw conclusions. On this basis we reach the conclusion that teachers want to make it possible for their pupils to make change and that the most important thing in teaching is to make it concrete and close to everyday life. The challenges that the teachers face is that the subject is unprioritized, that there is a lack of didactical material, a need of personal engagement and that the subject is rather complex. Based on our selective traditions we draw further conclusions. Traces of all three selective traditions are visible in the school and in the individual teachers’ teaching. Furthermore, some teachers express that the aim for their education is linked to one tradition, but their actual method is another.
27

CFD-simulations of urea-waterspray in an after-treatment systemusing Star-CCM+

Trigell, Emelie January 2018 (has links)
The legislation has forced the vehicle industry to reduce tail-end emissions. The air pollutant nitrogen oxide (NOX) has been shown to have a negative impact on human health and the environment. One of the key technologies to reduce the levels of NOX emitted from a vehicle is by implementing an after-treatment system. The after-treatment system includes catalysts, a particle filter and an evaporation system. In the evaporation system a liquid jet containing a urea-water solution known as AdBlue is injected into the hot exhaust gases to evaporate into gaseous ammonia NH3 and water H2O. Then NH3 enters the Selective Catalytic Reduction (SCR) catalyst where it chemically reacts with NOX to form N2 and H2O. Problems can arise if an excessive amount of AdBlue is injected and a fluid film is formed on evaporation surfaces. At certain operating conditions the fluid film can crystallise and form solid deposits. The solid deposits can cause high back-pressure, material deterioration and ammonia slip. This project is done in collaboration with Scania CV AB. Scania is a world-leading manufacturer of heavy-duty vehicles, busses and engines. Scania works continuously to develop new simulation methods to capture the complex phenomena of AdBlue spray, wall film dynamics and risk of solid deposits, to use in the development process of new components. The aim of this project is to implement and evaluate a new method to predict the risk of crystallisation of urea (AdBlue) using the software Star-CCM+. Two different geometries are studied, a test rig and a Scania silencer. Different operating conditions, parameter settings and a speed-up method are analysed. During the project a base-line model has been created and the results have been compared with measurement results and the software AVL Fire. The results on the test rig show the effect of altering the mesh and important model parameters. Injected particles are grouped into parcels with the same properties. The number of parcels is a crucial factor for the wall film formation and should be sufficiently high to get a statistical representation of the droplet size distribution. The results from the real silencer show strong evaporation and thin wall film formation with the suggested method. The method is shown to be stable and the software is user-friendly. A speed-up method was investigated to decrease the computational time. The computational time was reduced by a factor 20. The outcome of this project is a guide for set-up of AdBlue spray and wall film simulations. Recommendations to future work includes further validation of the settings, investigation of the evaporation rate and droplet size distribution and the application to other cases. The next step is also to tune the critical thresholds for deposit risk assessment. / Lagstiftning har tvingat fordonstillverkare att minska avgasutsläppen. Luftföroreningen kväveoxid (NOX) har visat sig ha en negativ inverkan på människors hälsa och på miljön. En viktig teknik för att minska utsläppen av NOX ¨ar att implementera ett efterbehandlingssystem. Efterbehandlingssystemet tar hand om avgaserna genom substrat, filter och ett förångningssystem. I förångningssystemet sprutas en urea-vattenlösning, som kallas AdBlue, in i de heta avgaserna där den förångas till ammoniak NH3 och vatten H2O. Ammoniakgasen leds därefter in till SCR katalysatorn där den kemiskt reagerar med NOX och bildar kvävgas N2 och vattenånga. Problem kan uppstå om fel mängd AdBlue sprutas in, då kan vätska byggas upp på förångsningsytor, kristallisera och bilda avlagringar. Avlagringarna kan bygga upp en solid klump som kan orsaka ett högt mottryck, nedbrytning av material och ammoniakslip. Detta arbete är ett samarbete med Scania CV AB som är en världsledande producent av lastbilar, bussar och motorer. Scania arbetar kontinuerligt med att utveckla nya simuleringsvertyg för att beskriva uppkomsten av Urea avlagringar för att använda i utvecklingen av nya komponenter. Syftet med detta arbete är att implementera och utvärdera en ny metod för att prediktera klump mha simuleringsverktyget Star-CCM+. Två olika geometrier är använd i arbetet: en testrigg och en av Scanias ljuddämpare. Olika driftspunkter, parametrar och en uppsnabbad metod är studerade. Under projektets gång har en modell byggts upp och jämförts med mätningar och simuleringar från programvaran AVL Fire. Resultatet från simuleringarna på testriggen visar effekten av att variera olika parametrar. Partiklarna som sprutas in i systemet är grupperade i paket med liknande egenskaper. Antalet paket påverkar uppbyggnaden av väggfilm och det rekommenderas att denna parameter hålls hög för att statistiskt beskriva droppfördelningen av partiklar. Resultaten på ljuddämparen visar en stark förångning och en tunn väggfilm för samtliga driftspunkter. Den implementerade metoden har visat sig vara stabil och användarvänlig. En uppsnabbad metod har utvärderats för att minska beräkningstiden. Beräkningstiden kunde minskas med en faktor 20. Resultatet av arbetet är en guide för hur metoden implementeras och bör användas. Rekommendationer till framtida arbete är en fortsatt undersökning av parametrar, utvärdering av förångningsmodellen, validering av droppstorleksfördelningen och tillämpningen på andra geometrier. Nästa steg i utvecklingen skulle vara att kalibrera tröskelvärden för prediktering av klump.

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