23 resultados para Bas-relief
em Helda - Digital Repository of University of Helsinki
Resumo:
The light emitted by flat panel displays (FPD) can be generated in many different ways, such as for example alternating current thin film electroluminescence (ACTFEL), liquid crystal display (LCD), light emitting diode (LED), or plasma display panel (PDP) technologies. In this work, the focus was on ACTFEL devices and the goal was to develop new thin film processes for light emitting materials in ACTFEL devices. The films were deposited with the atomic layer deposition (ALD) method, which has been utilized in the manufacturing of ACTFEL displays since the mid-1980s. The ALD method is based on surface-controlled self-terminated reactions and a maximum of one layer of the desired material can be prepared during one deposition cycle. Therefore, the film thickness can be controlled simply by adjusting the number of deposition cycles. In addition, both large areas and deep trench structures can be covered uniformly. During this work, new ALD processes were developed for the following thin film materials: BaS, CuxS, MnS, PbS, SrS, SrSe, SrTe, SrS1-xSex, ZnS, and ZnS1-xSex. In addition, several ACTFEL devices were prepared where the light emitting material was BaS, SrS, SrS1-xSex, ZnS, or ZnS1-xSex thin film that was doped with Ce, Cu, Eu, Mn, or Pb. The sulfoselenide films were made by substituting the elemental selenium for sulfur on the substrate surface during film deposition. In this way, it was possible to replace a maximum of 90% of the sulfur with selenium, and the XRD analyses indicated that the films were solid solutions. The polycrystalline BaS, SrS, and ZnS thin films were deposited at 180-400, 120-460, and 280-500 °C, respectively, and the processes had a wide temperature range where the growth rate of the films was independent of the deposition temperature. The electroluminescence studies showed that the doped sulfoselenide films resulted in low emission intensity. However, the emission intensities and emission colors of the doped SrS, BaS, and ZnS films were comparable with those found in earlier studies. It was also shown that the electro-optical properties of the different ZnS:Mn devices were different as a consequence of different ZnS:Mn processes. Finally, it was concluded that because the higher deposition temperature seemed to result in a higher emission intensity, the thermal stability of the reactants has a significant role when the light emitting materials of ACTFEL devices are deposited with the ALD method.
Resumo:
"Radiodiskurssin kontekstualisointi prosodisin keinoin. Esimerkkinä viisi suurta ranskalaista 1900-luvun filosofia" Väitöskirja käsittelee puheen kontekstualisointia prosodisin keinoin. Toisin sanottuna työssä käsitellään sitä, miten puheen prosodiset piirteet (kuten sävelkulku, intensiteetti, tauot, kesto ja rytmi) ohjaavat puheen tulkintaa vanhastaan enemmän tutkittujen sana- ja lausemerkitysten ohella. Työssä keskitytään seitsemään prosodisesti merkittyyn kuvioon, jotka koostuvat yhden tai usean parametrin silmiinpistävistä muutoksista. Ilmiöitä käsitellään sekä niiden akustisten muotojen että tyypillisten esiintymisyhteyksien ja diskursiivisten tehtävien näkökulmasta. Aineisto koostuu radio-ohjelmista, joissa puhuu viisi suurta ranskalaista 1900-luvun filosofia: Gaston Bachelard, Albert Camus, Michel Foucault, Maurice Merleau-Ponty ja Jean-Paul Sartre. Ohjelmat on lähetetty eri radiokanavilla Ranskassa vuosina 1948–1973. Väitöskirjan tulokset osoittavat, että prosodisesti merkityt kuviot ovat moniulotteisia puheen ilmiöitä, joilla on keskeinen rooli sanotun kontekstualisoinnissa: ne voivat esimerkiksi nostaa tai laskea sanotun informaatioarvoa, ilmaista puhujan voimakasta tai heikkoa sitoutumista sanomaansa, ilmaista rakenteellisen kokonaisuuden jatkumista tai päättymistä, jne. Väitöskirja sisältää myös kontrastiivisia osia, joissa ilmiöitä verrataan erääseen klassisessa pianomusiikissa esiintyvään melodiseen kuvioon sekä erääseen suomen kielen prosodiseen ilmiöön. Tulokset viittaavat siihen, että tietynlaista melodista kuviota käytetään samankaltaisena jäsentämiskeinona sekä puheessa että klassisessa musiikissa. Lisäksi tulokset antavat viitteitä siitä, että tiettyjä melodisia muotoja käytetään samankaltaisten implikaatioiden luomiseen kahdessa niinkin erilaisessa kielessä kuin suomessa ja ranskassa. Yksi väitöskirjan osa käsittelee pisteen ja pilkun prosodista merkitsemistä puheessa. Tulosten mukaan pisteellä ja pilkulla on kummallakin oma suullinen prototyyppinsä: piste merkitään tyypillisesti sävelkulun laskulla ja tauolla, ja pilkku puolestaan sävelkulun nousulla ja tauolla. Merkittävimmät tulokset koskevat kuitenkin tapauksia, joissa välimerkki tulkitaan prosodisesti epätyypillisellä tavalla: sekä pisteellä että pilkulla vaikuttaisi olevan useita eri suullisia vastaavuuksia, ja välimerkkien tehtävät voivat muotoutua hyvin erilaisiksi niiden prosodisesta tulkinnasta riippuen.
Resumo:
Prepositioner är välkända för sin polysemi eller betydelsemångfald, och utgångspunkten för den här uppsatsen har varit ett intresse av att undersöka om det är möjligt att för en av de mest mångtydiga spanska prepositionerna, DE, finna en sammanhängande semantisk struktur, eller om det är nödvändigt att se de olika betydelserna som inbördes orelaterade. För att utreda den här frågan och ge den ett diakroniskt perspektiv undersöker jag i den här uppsatsen användningen av den spanska prepositionen DE i två romaner ur den spanska litteraturhistorien, Libro del caballero Zifar och El ingenioso hidalgo don Quijote de la Mancha, del I. Uppsatsen består av tre delar. I kapitel två ger jag en teoretisk översikt över spanskans prepositionssystem och prepositionerna beskrivs både ur syntaktisk och semantisk synvinkel. Dessutom presenteras den kognitiva grammatiken och dess synsätt på prepositioner. Huvuddelen av arbetet koncentrerar sig på att presentera prepositionen DE på två sätt och enligt två skilda metoder. I kapitel tre presenteras de olika kontextuella användningarna av DE enligt den traditionella, historisk-komparativa metoden. Med utgångspunkt i dessa kontextuella användningar ställer jag i kapitel fyra med stöd av den kognitiva grammatikens begreppssystem upp en semantisk nätverksmodell av de olika betydelser som jag fastställt för DE i den funktionella analysen. För den semantiska beskrivningen har jag använt mig av den kognitiva grammatiken, eftersom denna grammatikuppfattning i motsats till den traditionella grammatiken ser polysemin som regel och utgångspunkt i den semantiska strukturen. Analysdelen av uppsatsen inleds med den funktionella presentationen av användningarna av DE av två grundläggande skäl: För det första anser jag det ändamålsenligt att för den semantiska beskrivningen ha en solid bas av exempel där användningen av DE analyserats med hänsyn till kontexten. Kapitel tre är därför indelat i fyra huvuddelar, enligt vilken ordklass DEs huvudord tillhör, t.ex.: substantiv, adjektiv, verb. I exemplen i den fjärde gruppen fungerar prepositionsfrasen som inleds av DE som en mer fristående bestämning på frasnivå, där huvudordets ordklasstillhörighet inte är av avgörande betydelse. För det andra utgår jag från att en viss utveckling av DE har skett under de 300 år som tidsmässigt skiljer de båda romanerna åt, både vad gäller dess användning och dess semantik. För att komma underfund med och beskriva utsträckningen hos denna utveckling är det nödvändigt att den komparativa delen presenteras innan den semantiska beskrivningen kan inledas. Resultaten av den komparativa analysen är att ett antal smärre skillnader i användningen förekommer, men detta till trots har ingen betydande semantisk utveckling kunnat iakttas. Detta innebär att den semantiska beskrivningen av DE kan göras utifrån ett relativt enhetligt material. Jag har följaktligen också kunnat ställa upp en enhetlig semantisk nätverksmodell av tolv olika, relaterade betydelser hos DE. Utgående från mitt material är det sålunda möjligt att se DEs polysemi som ett sammanhängande nätverk, trots att vissa av betydelserna kan verka sinsemellan motstridiga och att 300 år skiljer åt de två böckerna. Nyckelord: prepositioner, DE: semantik och användning, polysemi, kognitiv grammatik, diakroni
Resumo:
The development of a simple method of coating a semi-permanent phospholipid layer onto a capillary for electrochromatography use was the focus of this study. The work involved finding good coating conditions, stabilizing the phospholipid coating, and examining the effect of adding divalent cations, cetyltrimethylammonium bromide, and polyethylene glycol (PEG)-lipids on the stability of the coating. Since a further purpose was to move toward more biological membrane coatings, the capillaries were also coated with cholesterol-containing liposomes and liposomes of red blood cell ghost lipids. Liposomes were prepared by extrusion, and large unilamellar vesicles with a diameter of about 100 nm were obtained. Zwitterionic phosphatidylcholine (PC) was used as a basic component, mainly 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine (POPC) but also eggPC and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Different amounts of sphingomyelin, bovine brain phosphatidylserine, and cholesterol were added to the PC. The stability of the coating in 40 mM N-(2-hydroxyethyl)piperazine-N’-(2-ethanesulfonic acid) (HEPES) solution at pH 7.4 was studied by measuring the electroosmotic flow and by separating neutral steroids, basic proteins, and low-molar-mass drugs. The presence of PC in the coating solution was found to be essential to achieving a coating. The stability of the coating was improved by the addition of negative phosphatidylserine, cholesterol, divalent cations, or PEGylated lipids, and by working in the gel-state region of the phospholipid. Study of the effect on the PC coating of divalent metal ions calcium, magnesium, and zinc showed a molar ratio of 1:3 PC/Ca2+ or PC/Mg2+ to give increased rigidity to the membrane and the best coating stability. The PEGylated lipids used in the study were sterically stabilized commercial lipids with covalently attached PEG chains. The vesicle size generally decreased when PEGylated lipids of higher molar mass were present in the vesicle. The predominance of discoidal micelles over liposomes increased PEG chain length and the average size of the vesicles thus decreased. In the capillary electrophoresis (CE) measurements a highly stable electroosmotic flow was achieved with 20% PEGylated lipid in the POPC coating dispersion, the best results being obtained for disteroyl PEG (3000) conjugates. The results suggest that smaller particles (discoidal micelles) result in tighter packing and better shielding of silanol groups on the silica wall. The effect of temperature on the coating stability was investigated by using DPPC liposomes at temperatures above (45 C) and below (25 C) the main phase transition temperature. Better results were obtained with DPPC in the more rigid gel state than in the fluid state: the electroosmotic flow was heavily suppressed and the PC coating was stabilized. Also dispersions of DPPC with 0−30 mol% of cholesterol and sphingomyelin in different ratios, which more closely resemble natural membranes, resulted in stable coatings. Finally, the CE measurements revealed that a stable coating is formed when capillaries are coated with liposomes of red blood cell ghost lipids.
Resumo:
The dissertation focuses on the recognition of the problems of uneven regional development in Finland in the 1950s, and the way the idea of controlling this development was introduced to Finnish politics. Since it is often stated that Finnish regional policy only began in the mid-1960s, the period at hand is considered to fall in the time before regional policy. However, various ideas, plans and projects of regional development as well as different aims of development were brought forward and discussed already in the 1950s. These give an interesting perspective to the ideas of later regional development. In the 1950s, many Finnish politicians became more conscious of the unavoidable societal change. The need for overall modernisation of the society made it reasonable to expect a growing level of unemployment and eagerness to migration. The uneven distribution of well-being was also feared to cause discontent and political changes. International experience proved interfering in the regional development possible when using the argument of public interest ; the measures taken increased the level of well-being, helped sustain societal balance, and supported national economy. Many of the development projects of the 1950s focused on Northern Finland, the natural resources of which were considered an important reserve and the political climate of which was regarded unstable. After the late 1940s, regional development was discussed frequently both on the national and the regional level. Direct and indirect support was given to less developed areas and the government outlined thorough investigations in order to relieve the regional problem. Towards the end of the decade, the measures taken were already often connected to the idea of equality. In the 1950s the conflicts within and between the largest Finnish political parties significantly affected the decisions of regional development. There are three case studies in this qualitative research based on the narrative method. The case studies clarify the characteristics of the 1950s regional development. In the first one, the representatives of the northern region and the state first discuss the location of a state-run nitrogen fertilizer factory and later the location of a new university. In the second, the aims and perspectives of private entrepreneurs and the state collide due to ideas of statist industrialisation projects and later due to an idea of a tax relief targeting northern industry. In the third case, the main role is given to the changing rural areas, in relation to which societal development and urbanisation were often measured. The regional development of the 1950s laid groundwork for the new, more established regional policy. The early problem solving actions were aimed both at the prevailing situation and the future and thus showed the way for the upcoming actions. Regional development policy existed already before regional policy.
Resumo:
One of the most tangled fields of research is the field of defining and modeling affective concepts, i. e. concepts regarding emotions and feelings. The subject can be approached from many disciplines. The main problem is lack of generally approved definitions. However, e.g. linguists have recently started to check the consistency of their theories with the help of computer simulations. Definitions of affective concepts are needed for performing similar simulations in behavioral sciences. In this thesis, preliminary computational definitions of affects for a simple utility-maximizing agent are given. The definitions have been produced by synthetizing ideas from theories from several fields of research. The class of affects is defined as a superclass of emotions and feelings. Affect is defined as a process, in which a change in an agent's expected utility causes a bodily change. If the process is currently under the attention of the agent (i.e. the agent is conscious of it), the process is a feeling. If it is not, but can in principle be taken into attention (i.e. it is preconscious), the process is an emotion. Thus, affects do not presuppose consciousness, but emotions and affects do. Affects directed at unexpected materialized (i.e. past) events are delight and fright. Delight is the consequence of an unexpected positive event and fright is the consequence of an unexpected negative event. Affects directed at expected materialized (i.e. past) events are happiness (expected positive event materialized), disappointment (expected positive event did not materialize), sadness (expected negative event materialized) and relief (expected negative event did not materialize). Affects directed at expected unrealized (i.e. future) events are fear and hope. Some other affects can be defined as directed towards originators of the events. The affect classification has also been implemented as a computer program, the purpose of which is to ensure the coherence of the definitions and also to illustrate the capabilities of the model. The exact content of bodily changes associated with specific affects is not considered relevant from the point of view of the logical structure of affective phenomena. The utility function need also not be defined, since the target of examination is only its dynamics.
Resumo:
On the material level of poverty, the work shows how the Great Depression forced rural women and children to enhance their work input and find new ways of coping. The most serious impact of the Depression was poor nutrition, as well as scarcity of food and clothes. Women's and men's ways to make a living started to resemble each other; men had also to consent to wages in form of foodstuff. The research also focuses on immaterial poverty by means of exploring experiences of otherness: shame, hatred and expressions of protest. Substantial humiliation was induced by poor relief and begging. A clear gap prevailed between the poor and the better off people in school, work and at leisure. The economic crisis deepened this gap even further. The dissertation specifies the poor people s every day experiences by taking into account the different worlds of men and women. The analysis of four different memory-based sources is the core in the micro-historical research design. The narrators of the research were survivors, unlike many others, who experienced the Great Depression. Moralization and humiliation of the poor have not ceased in contemporary society. Therefore, the historical perspective of both the material and the immaterial side of poverty could increase the understanding of the multifaceted phenomenon of today s poverty.
Resumo:
The philosophical problem of self-deception focuses the relation between desire, advantage, evidence and harm. A self-deceptive person is irrational because he or she belives or wants to belive contrary to the available evidence. The study focuses on different forms of self-deception that come out in certain classical Western dramas. The first self-deception forms are: "S knows that ~p but still belives that p because he wants that ~p", "S wants that p and therefore belives that p.", "S belives that p against evidence t because he wants to belive that p.", "S belives that p if t but S would belive that p even if ~t because S wants to belive that p.", "S belives that p (even if there is t that ~p) because S is ignorant of it." and "S belives that p (even if there is t that ~p) because of ignorant of t due to an internal deception." The main sources on self-deception are the views of contemporary researchers of the subject, such as Robert Audi, Marcia Baron, Bas C. van Fraassen, Mark Johnston, Mike W. Martin, Brian MaLaughlin, Alfred Mele, Amélie Oksenberg Rorty, William Ruddick and Stephen L. White. In this study it is claimed that Shakespeare´s Othello presents self-deception as a tragic phenomenom from witch it follows deceptions and murders. Moliére´s Tartuffe deals with a phony hypocrite´s attempts at cheating. Ibsen´s Wild Duck defends the necessity of vital lies. Beckett´s Waiting for Godot deals with the self-deception witch is related to the waiting of the supernatural rescuer. Miller´s The Death of a Salesman tells about a man who, while pursuing the American myth of success, winds both himself and his family into the skeins of self-deception. They are studied with a Barthesian method that emphasizes the autonomy of literary work and its interpretation independently of the author´s personal history and social conditions. Self-deception has been regarded as an immoral way of thinking or way of action. However, vital lies show the necessity or necessity of the self-deception when it brings joy and optimism to the human being and supports his or her self-esteem and does not cause a suffering or damage, either to self or others. In the study, the processual character of self-deception is brought out.
Resumo:
This thesis aims at finding the role of deposit insurance scheme and central bank (CB) in keeping the banking system safe. The thesis also studies the factors associated with long-lasting banking crises. The first essay analyzes the effect of using explicit deposit insurance scheme (EDIS), instead of using implicit deposit insurance scheme (IDIS), on banking crises. The panel data for the period of 1980-2003 includes all countries for which the data on EDIS or IDIS exist. 70% of the countries in the sample are less developed countries (LDCs). About 55% of the countries adopting EDIS also come from LDCs. The major finding is that the using of EDIS increases the crisis probability at a strong significance level. This probability is greater if the EDIS is inefficiently designed allowing higher scope of moral hazard problem. Specifically, the probability is greater if the EDIS provides higher coverage to deposits and if it is less powerful from the legal point of view. This study also finds that the less developed a country is to handle EDIS, the higher the chance of banking crisis. Once the underdevelopment of an economy handling the EDIS is controlled, the EDIS separately is no longer a significant factor of banking crises. The second essay aims at determining whether a country s powerful CB can lessen the instability of the banking sector by minimizing the likelihood of a banking crisis. The data used include indicators of the CB s autonomy for a set of countries over the period of 1980-89. The study finds that in aggregate a more powerful CB lessens the probability of banking crisis. When the CB s authority is disentangled with respect to its responsibilities, the study finds that the longer tenure of CB s chief executive officer and the greater power of CB in assigning interest rate on government loans are necessary for reducing the probability of banking crisis. The study also finds that the probability of crisis reduces more if an autonomous CB can perform its duties in a country with stronger law and order tradition. The costs of long-lasting banking crises are high because both the depositors and the investors lose confidence in the banking system. For a rapid recovery of a crisis, the government very often undertakes one or more crisis resolution policy (CRP) measures. The third essay examines the CRP and other explanatory variables correlated with the durations of banking crises. The major finding is that the CRP measure allowing the regulation forbearance to keep the insolvent banks operative and the public debt relief program are respectively strongly and weakly significant to increase the durations of crises. Some other explanatory variables, which were found by previous studies to be related with the probability of crises to occur, are also correlated with the durations of crises.
Resumo:
Urbanization leads to irreversible land-use change, which has ecological consequences such as the loss and fragmentation of green areas, and structural and functional changes in terrestrial and aquatic ecosystems. These consequences diminish ecosystem services important for human populations living in urban areas. All this results in a conflict situation: how to simultaneously meet the needs of city growth and the principles of sustainable development, and especially conserve important green areas within and around built-up areas? Urban planners and decisionmakers have an important role in this, since they must use the ecological information mainly from species and biotope inventories and biodiversity impact assessments in determining the conservation values of green areas. The main aim of this thesis was to study the use of ecological information in the urban land-use planning and decisionmaking process in the Helsinki Metropolitan Area, Finland. At first, the literature on ecological-social systems linkages related to urban planning was reviewed. Based on the review, a theoretical and conceptual framework for the research on Finnish urban setting was adapted. Secondly, factors determining the importance and effectiveness of incorporation of ecological information into the urban planning process, and the challenges related to the use of ecological information were studied. Thirdly, the importance and use of Local Ecological Knowledge in urban planning were investigated. Then, factors determining the consideration of urban green areas and related ecological information in political land-use decisionmaking were studied. Finally, in a case study illustrating the above considerations, the importance of urban stream ecosystems in the land-use planning was investigated. This thesis demonstrated that although there are several challenges in using ecological information effectively, it is considered as an increasingly important part of the basic information used in urban planning and decisionmaking process. The basic determinants for this are the recent changes in environmental legislation, but also the increasing appreciation of green areas and their conservation values by all the stakeholders. In addition, Local Ecological Knowledge in its several forms can be a source of ecological information for planners if incorporated effectively into the process. This study also showed that rare or endangered species and biotopes, and related ecological information receive priority in the urban planning process and usually pass through the decisionmaking system. Furthermore, the stream Rekolanoja case indicates that planners and residents see the value of urban stream ecosystem as increasingly important for the local health and social values, such as recreation and stress relief.
Resumo:
Double-stranded RNA (dsRNA) viruses encode only a single protein species that contains RNA-dependent RNA polymerase (RdRP) motifs. This protein is a central component in the life cycle of a dsRNA virus, carrying out both RNA transcription and replication. The architecture of viral RdRPs resembles that of a 'cupped right hand' with fingers, palm and thumb domains. Those applying de novo initiation have additional structural features, including a flexible C-terminal domain that constitutes the priming platform. Moreover, viral RdRPs must be able to interact with the incoming 3'-terminus of the template and position it so that a productive binary complex is formed. Bacteriophage phi6 of the Cystoviridae family is to date one of the best studied dsRNA viruses. The purified recombinant phi6 RdRP is highly active in vitro and possesses both RNA replication and transcription activities. The extensive biochemical observations and the atomic level crystal structure of the phi6 RdRP provides an excellent platform for in-depth studies of RNA replication in vitro. In this thesis, targeted structure-based mutagenesis, enzymatic assays and molecular mapping of phi6 RdRP and its RNA were used to elucidate the formation of productive RNA-polymerase binary complexes. The positively charged rim of the template tunnel was shown to have a significant role in the engagement of highly structured ssRNA molecules, whereas specific interactions further down in the template tunnel promote ssRNA entry to the catalytic site. This work demonstrated that by aiding the formation of a stable binary complex with optimized RNA templates, the overall polymerization activity of the phi6 RdRP can be greatly enhanced. Furthermore, proteolyzed phi6 RdRPs that possess a nick in the polypeptide chain at the hinge region, which is part of the extended loop, were better suited for catalysis at higher temperatures whilst favouring back-primed initiation. The clipped C-terminus remains associated with the main body of the polymerase and the hinge region, although structurally disordered, is involved in the control of C-terminal domain displacement. The accumulated knowhow on bacteriophage phi6 was utilized in the development of two technologies for the production of dsRNA: (i) an in vitro system that combines the T7 RNA polymerase and the phi6 RdRP to generate dsRNA molecules of practically unlimited length, and (ii) an in vivo RNA replication system based on restricted infection with phi6 polymerase complexes in bacterial cells to produce virtually unlimited amounts of dsRNA. The pools of small interfering RNAs derived from dsRNA produced by these systems were validated and shown to efficiently decrease the expression of both exogenous and endogenous targets.
Resumo:
Migraine is a common disease in children and adolescents, affecting roughly 10% of school-aged children. Recent studies have revealed an increasing incidence of childhood migraine, but migraine remains an underrecognized and undertreated condition in the pediatric population. Migraine attacks are painful and disabling and can affect a child´s life in many ways. Effective drug treatment is usually needed. The new migraine drugs, triptans, were introduced at the beginning of the 1990s and have since been shown to be very effective in the treatment of migraine attacks in adults. Although they are widely used in adults, the acute treatment of migraine in children and adolescents is still based on paracetamol and nonsteroidal anti-inflammatory drugs. Some children can control their attacks satisfactorily with simple analgesics, but at least one-third need more powerful treatments. When this thesis work commenced, hardly any information existed on the efficacy and safety of triptans in children. The study aim of the thesis was to identify more efficient treatments of migraine for children and adolescents by investigating the efficacy of sumatriptan nasal spray and oral rizatriptan compared with placebo in them. Sleep has an impact on migraine in many aspects. Despite the clinical relevance and common manifestation of sleep in the context of migraine in children, very little research data on the true frequency of sleep exist. As sleeping is so often related to childhood migraine, it can be a confounding factor in clinical drug trials of migraine treatments in children and adolescents. How the results of a sleeping child should be analyzed is under continual debate. The aim of the thesis was also to clarify this as well as to evaluate the frequency of sleeping during migraine attacks in children and factors affecting frequency. Both nasal sumatriptan and oral rizatriptan were effective (superior to placebo), and well tolerated in treatment of migraine attacks in children and adolescents aged 8-17 and 6-17 years, respectively. No serous adverse effects were observed. The results of this work suggest that nasal sumatriptan 20 mg and rizatriptan 10 mg can be effectively and safely used to treat migraine attacks in adolescents aged over 12 years if more effective drugs than NSAIDs are needed. No difference was observed in efficacy or safety of nasal sumatriptan and rizatriptan between children aged younger than 12 years and older children, but because the treated number of patients under 12 years is still small, more studies are needed before sumatriptan or rizatriptan can be recommended for use in this population. Sleeping during migraine attacks was very common, and most children at least occasionally slept during an attack. Falling asleep was especially common in children under eight years of age and during the first hour after the onset of attack. Children who were able to sleep soon after attack onset were more likely pain-free at two hours. Sleeping probably both improves recovery from a migraine attack and is a sign of headache relief. Falling asleep should be classified as a sign of headache relief in clinical drug trials when studying migraine treatments in children and adolescents.
Resumo:
The aims of this study were to describe Finnish day surgery practice at present and to evaluate quality of care by assessing postdischarge minor morbidity and quality indicators. Potential treatment options were approached by investigating the role of oral dexamethasone as a part of multimodal analgesia and the feasibility of day surgery in patients aged 65 years and older. Over a 2-month period, all patient cases at 14 Finnish day surgery or short-stay units were analyzed (Study I). Quality indicators included rates and reasons for overnight admission, readmission, reoperation, cancellations, and patient satisfaction. Recovery during the first postoperative week was assessed at two units (Study II). Altogether 2732 patients graded daily the intensity of predefined symptoms. To define risk factors of postdischarge symptoms, multinomial regression analysis was used. Sixty patients scheduled to undergo day surgery for hallux valgus were randomized to receive twice perioperatively dexamethasone 9 mg or placebo (Study III). Paracetamol 1 g was administered 3 times daily. Rescue medication (oxycodone) consumption during 0-3 postoperative days (POD), maximal pain scores and adverse effects were documented. Medically stable patients aged 65 years or older, scheduled for open inguinal hernia repair, were randomized to receive treatment either as day cases or inpatients (Study IV). Complications, unplanned admissions, healthcare visits, and patients’ acceptance of the type of care provided were assessed during 2 weeks postoperatively. In Study I, unplanned overnight admissions were reported in 5.9%, return hospital visits during PODs 1-28 in 3.7%, and readmissions in 0.7% of patients. Patient satisfaction was high. In Study II, pain was the most common symptom in adult patients (57%). Postdischarge symptoms were more frequent in adults aged < 40 years, children aged ≥ 7 years, females, and following a longer duration of surgery. In Study III, the total median (range) oxycodone consumption during the study period was 45 (0–165) mg in the dexamethasone group, compared with 78 (15–175) mg in the placebo group (P < 0.049). On PODs 0-1, patients in the dexamethasone group reported significantly lower pain scores. Following inguinal hernia repair, no significant differences in outcome measures were seen between the study groups. Patient satisfaction was equally high in day cases and inpatients (Study IV). Finnish day surgery units provide good-quality services. Minor postdischarge symptoms are common, and they are influenced by several patient-, surgery-, and anesthesia-related factors. Oral dexamethasone combined with paracetamol improves pain relief and reduces the need for oxycodone rescue medication following correction of hallux valgus. Day surgery for open inguinal hernia repair is safe and well accepted by patients aged 65 years or older and can be recommended as the primary choice of care for medically stable patients.
Resumo:
Continuous epidural analgesia (CEA) and continuous spinal postoperative analgesia (CSPA) provided by a mixture of local anaesthetic and opioid are widely used for postoperative pain relief. E.g., with the introduction of so-called microcatheters, CSPA found its way particularly in orthopaedic surgery. These techniques, however, may be associated with dose-dependent side-effects as hypotension, weakness in the legs, and nausea and vomiting. At times, they may fail to offer sufficient analgesia, e.g., because of a misplaced catheter. The correct position of an epidural catheter might be confirmed by the supposedly easy and reliable epidural stimulation test (EST). The aims of this thesis were to determine a) whether the efficacy, tolerability, and reliability of CEA might be improved by adding the α2-adrenergic agonists adrenaline and clonidine to CEA, and by the repeated use of EST during CEA; and, b) the feasibility of CSPA given through a microcatheter after vascular surgery. Studies I IV were double-blinded, randomized, and controlled trials; Study V was of a diagnostic, prospective nature. Patients underwent arterial bypass surgery of the legs (I, n=50; IV, n=46), total knee arthroplasty (II, n=70; III, n=72), and abdominal surgery or thoracotomy (V, n=30). Postoperative lumbar CEA consisted of regular mixtures of ropivacaine and fentanyl either without or with adrenaline (2 µg/ml (I) and 4 µg/ml (II)) and clonidine (2 µg/ml (III)). CSPA (IV) was given through a microcatheter (28G) and contained either ropivacaine (max. 2 mg/h) or a mixture of ropivacaine (max. 1 mg/h) and morphine (max. 8 µg/h). Epidural catheter tip position (V) was evaluated both by EST at the moment of catheter placement and several times during CEA, and by epidurography as reference diagnostic test. CEA and CSPA were administered for 24 or 48 h. Study parameters included pain scores assessed with a visual analogue scale, requirements of rescue pain medication, vital signs, and side-effects. Adrenaline (I and II) had no beneficial influence as regards the efficacy or tolerability of CEA. The total amounts of epidurally-infused drugs were even increased in the adrenaline group in Study II (p=0.02, RM ANOVA). Clonidine (III) augmented pain relief with lowered amounts of epidurally infused drugs (p=0.01, RM ANOVA) and reduced need for rescue oxycodone given i.m. (p=0.027, MW-U; median difference 3 mg (95% CI 0 7 mg)). Clonidine did not contribute to sedation and its influence on haemodynamics was minimal. CSPA (IV) provided satisfactory pain relief with only limited blockade of the legs (no inter-group differences). EST (V) was often related to technical problems and difficulties of interpretation, e.g., it failed to identify the four patients whose catheters were outside the spinal canal already at the time of catheter placement. As adjuvants to lumbar CEA, clonidine only slightly improved pain relief, while adrenaline did not provide any benefit. The role of EST applied at the time of epidural catheter placement or repeatedly during CEA remains open. The microcatheter CSPA technique appeared effective and reliable, but needs to be compared to routine CEA after peripheral arterial bypass surgery.