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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.
181

Vokalkvalitet och duration hos diftonger i benadiri och nordsomaliska / Vowel quality and duration of diphthongs in Benadiri and northern Somali

Franzén, Johan January 2013 (has links)
I beskrivningar av somaliska noteras i vissa kontexter en dialektal variation i vokalkvalitet och duration mellan sydsomaliska (benadiri) och nordsomaliska. Modersmålstalare av somaliska bekräftar noterade dialektala skillnader i vokalkvalitet och duration, och anser att det finns en possessivändelse på benadiri eey vilken skiljer sig från den nordsomaliska motsvarigheten ay. Undersökningen syftade till att ta reda på om och på vilket sätt vokalkvalitet och duration varierar, i diftongen ay i de somaliska dialekterna sydsomaliska (benadiri) och nordsomaliska. Studien begränsades till mätning av vokalkvalitet och duration i possessivändelsen -ay. Värden för F1 och F2 i diftongens initialfas, såväl som diftongens duration, mättes i uttal som av modersmålstalare kategoriserats som nordsomaliska respektive sydsomaliska. De uppmätta skillnaderna i vokalkvalitet motsvarade förväntningarna. Genomsnittliga värden för F1 och F2 var lägre respektive högre i samtliga mätgrupper för de uttal som av modersmålstalare klassificerats som sydliga, än för de som klassificerats som nordliga. Det noterades dock att avståndet mellan diftongerna i nordliga och sydliga uttal var betydligt större i ordet aabahay än i hooyaday. Orsaken till detta bör utredas vidare, med fokus på kontextuella skillnader. Endast en obetydlig genomsnittlig durationsskillnad uppmättes. Ett förväntat samband i längdskillnad mellan sydligt och nordligt klassificerade uttal kunde således ej konstateras. / Descriptions of the Somali dialects include a variation in vowel quality and duration, between southern Somali (Benadiri) and northern Somali. Native speakers of Somali confirm noted variations and describe a possessive ending eey in Benadiri, different from the northern Somali equivalent ay. This survey aimed to investigate if, and how, vowel quality and duration vary in the diphthong ay in southern Somali and northern Somali. This study was limited to measuring vowel quality and duration of the possessive ending -ay. Values of F1 and F2 in the initial phase of the diphthong, as well as the duration, were measured in pronunciations, which native speakers have labeled as northern or southern respectively. The measured differences in vowel quality were in line with the expectations. Mean values of F1 and F2 were lower/higher in all measuring groups for the pronunciations labeled as southern, than for those labeled as northern. It was noted, however, that the distance between the diphthongs in northern and southern Somali, was significantly larger in the word aabahay than in hooyaday. The reason for this should be investigated further, focusing on contextual differences. The expected difference in duration between the southern and northern pronunciations could not be found. / <p>Institutionen för lingvistik</p><p>Examensarbete för kandidatexamen 15 hp</p><p>Fonetik</p><p>Kandidatprogram i lingvistik</p><p>Vårterminen 2013</p><p>Handledare: Mattias Heldner</p><p>Examinator: Henrik Liljegren</p><p>English title: Vowel quality and duration of diphthongs in Benadiri and northern Somali </p>
182

Transjugular Intrahepatic Portosystemic Shunt (Tips), Duration of Procedural Time and Correlation with Early Morbidity and Mortality

Barrera Gutierrez, Juan Carlos 13 August 2021 (has links)
No description available.
183

En jämförelse av kortikal registrering mellan olika registreringspunkter vid Somatosensory evoked potentials / Comparison between cortical registration from different registration markers with Somatosensory evoked potentials

Salian, Dilip January 2020 (has links)
Bakgrund- Sensorisk evoked potentials (SEP) är en neurofysiologisk undersökningsmetod som används för att monitorera svarspotentialer från kroppens sensoriska nervsystem efter en sensorisk stimulering. Registreringen av sensorisk evoked potentials sker med små elektriska stimuleringar över en perifer sensorisk nerv och registreras från tre olika registreringskanaler som benämns N9 över plexus brachialis, N13 Erb’s punkt och N20 för det primär sensoriska cortexområdet. Metod- I denna studie bearbetas data från 20 registreringar för N20-kanalen. Med registreringen av den klinisk använda standardmontaget C3’-Fz som används vid Karolinska universitetssjukhuset, som jämförs mot nya registreringsmontagen C3’-CPz, CP3-Fz CP3-CPz. Stimulering skedde unilateralt över höger nervus medianus på handledsnivå. Syftet med studien var att ta reda på om det fanns någon statistisk signifikant skillnad mellan standardmontaget C3’-Fz mot de alternativa montagen med avseende på amplitud, duration och latenstid mellan två registreringsomgångar. Den statistiska analysen genomfördes med Wilcoxsons teckenranktest för differenserna av registreringsomgångarna i amplitud, duration och latenstid. Spearmans rangkorrelationstest användes för att visa sambandet mellan standardmontaget och de nya registreringsmontagen i amplitud. Resultat- Resultatet visade ingen statistisk signifikant skillnad mellan standardmontaget mot de alternativa montagen för differenserna av amplitud, duration och latenstid mellan de två registringsomgångarna. Korrelationen för amplituderna visade att montaget CP3-Fz hade en starkare grad av samband mot standardmontaget C3’-Fz jämfört med registreringsmontagen C3’-CPz och CP3-CPz. Slutsats- Slutsatsen av denna studie är att det inte fanns någon statistisk signifikant skillnad i differenserna för amplitud, duration och latenstiderna vid jämförelse av standardmontaget mot de nya alternativa montagen. Dock visade montage CP3-Fz på ett starkare samband mot den klinisk använda C3-Fz jämfört med resterande montage med avseende på amplituden. / Background-Sensory evoked potentials (SEP) are a neurophysiological examination method used to monitor electrical response potentials from the body’s sensory nervous system. The registration follows three recording channels throughout the sensory pathway as N9 over plexus brachialis, N13 over cervical vertebrae mentioned as Erb’ point and N20 represented for the primary somatosensory cortex area. Method- In this study data was collected from 20 registrations for N20 channel. Registration for this study measured the clinical used cortical registration montage at Karolinska university hospital C3’-Fz against new registration montages C3'-CPz, CP3-Fz and CP3-CPz, with stimulation on the right median nerve at wrist level unilateral. The purpose of the study was to see if there exists any significant difference between the standard montage C3’-Fz against the new alternative registration montages in regard to amplitude, duration and latency after two registration rounds. Wilcoxson’s singed rank test were used to compare the difference in amplitude, duration and latency between registration rounds. Spearman’s correlation test were used to show the correlation between the standard montage and the new registration montages in amplitude. Result-The result showed no statistical significant difference between the standard montage and the new alternative montages in amplitude, duration and latency for the two registration rounds. The correlation showed registration montage CP3-Fz with a greater correlation towards the standard montage C3’-Fz compared to registration montages C3’-CPz and CP3-CPz in amplitude. Conclusions- This study showed no significant difference in amplitude, duration and latency when it compared the standard montage C3’-Fz against the new alternative montages. The correlation in amplitude showed montage Cp3-Fz with a stronger correlation towards the clinical used registration montage compared to the other new alternative montages.
184

Sensorisk elektroneurografi på nervus medianus vid två olika stimuleringspunkter : En jämförelse av hur amplitud och duration skiljer mellan distal och proximal stimuleringspunkt vid antidrom sensorisk neurografi / Sensory nerve conduction study on median nerve at two different stimulations sites : A comparison of how amplitude and duration differ between distal and proximal stimulation site in antidrome sensory neurography

Hussein, Najmo Mohamed January 2021 (has links)
Elektroneurografi är en grundläggande icke invasiv metod som används dagligen inom kliniska verksamheter för att diagnostisera olika perifera nervsjukdomar. Metoden speglar den funktionella statusen av de myeliniserade motoriska och sensoriska axonen. Vid sensorisk neurografi mäts sensory nerve actionpotential (SNAP) som är summan av alla aktionspotentialer som är genererade av enskilda myeliniserade axon. Vid undersökningen erhålls olika variabler som är viktiga för diagnostik såsom amplitud, duration, latenstid och ledningshastighet.   Syftet med studien var att undersöka om det finns skillnad i amplitud och duration på sensory nerve actionpotential vid antidrom sensorisk stimulering av nervus medianus vid två olika stimuleringspunkter.   Nervus medianus stimulerades elektriskt distalt och proximalt hos 18 friska testpersoner med en hudtemperatur på minst 32°C. Antidrom sensorisk stimulering av nervus medianus vid två olika stimuleringspunkter visade att det förelåg en signifikant skillnad i amplitud och duration mellan distal och proximal stimuleringspunkt. Reproducerbarheten för metoden visades vara hög. / Electroneurography is a basic non-invasive method that is used daily in clinical practice to diagnose various peripheral nerve diseases. The method reflects the functional status of the myelinated motor and sensory axons. In sensory neurography, sensory nerve action potential (SNAP) is measured, which is the sum of all action potentials generated by individual myelinated axons. During the examination, various variables are obtained that are important for diagnostics, such as amplitude, duration, latency time and conduction velocity.    The aim of this study was to investigate whether there is a difference in amplitude and duration of sensory nerve action potential in antidrome sensory stimulation of the median nerve at two different stimulation sites.   The median nerve was stimulated electrically distally and proximally in 18 healthy subjects with a skin temperature of at least 32 ° C. Antidrome sensory stimulation of the median nerve at two different stimulation sites showed that there was a significant difference in amplitude and duration between distal and proximal stimulation sites. The reproducibility of the method was shown to be high.
185

Experiences from Cochlear Implantation and Auditory Brainstem Implantation in Adults and Children : Electrophysiological Measurements, Hearing Outcomes and Patient Satisfaction

Lundin, Karin January 2016 (has links)
Cochlear implants (CIs) and auditory brainstem implants (ABIs) are prostheses for hearing used in patients with profound hearing impairment. A CI requires an operational cochlear nerve to function in contrast to an ABI. ABIs were initially designed for adult patients with neurofibromatosis type 2 (NF2), suffering from bilateral vestibular schwannomas. Now ABIs are also used for patients, both adults and children, with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, and cochlear ossification. The aims of this thesis are to evaluate hearing outcome in patients implanted with a CI after long-term deafness. An extended period of deafness has earlier been considered as a contraindication for CI surgery. Further, we analyzed if electrically evoked auditory brainstem responses (eABRs) can predict CI outcome and pinpoint the optimal selection of treatment such as CI or ABI. We also disclose our experiences from ABI surgery in Uppsala, such as implant use, hearing outcome, complications, and satisfaction among the patients. Finally, we evaluated the results and benefits of ABIs in non-NF2 pediatric patients. Results show that patients with an extended deafness period and durations over 20 years can achieve speech understanding and benefit from CIs. Patients with long-term deafness and limited years of hearing before deafness did not perform as well as those with shorter deafness duration and longer hearing experience did. eABR seems to have a definite role in the diagnostic armamentarium, to better consider alternative surgical strategies such as ABI. No eABR waveform predicted a poor CI outcome. There was no correlation between speech perception and eABR waveform latencies or eABR waveform quality. A majority of the ABI patients used their ABIs and benefited from them for at least some period. ABI assisted voice control in a majority of the full-time users and they reported improved understanding of speech with the implant switched on. No severe complications from ABI surgery or ABI stimulation were noted. The patients were generally satisfied, even if their hearing remained very limited. All pediatric patients but one used the implant continuously and benefited from it.
186

Assessment of active commuting behaviour : walking and bicycling in Greater Stockholm

Stigell, Erik January 2011 (has links)
Walking and bicycling to work, active commuting, can contribute to sustainable mobility and provide regular health-enhancing physical activity for individuals. Our knowledge of active commuting behaviours in general and in different mode and gender groups in particular is limited. Moreover, the validity and reproducibility of the methods to measure the key variables of the behaviours are uncertain. The aims of this thesis is to explore gender and mode choice differences in commuting behaviours in terms of distance, duration, velocity and trip frequency, of a group of adult commuters in Greater Stockholm, Sweden, and furthermore to develop a criterion method for distance measurements and to assess the validity of four other distance measurement methods. We used one sample of active commuters recruited by advertisements, n = 1872, and one street-recruited sample, n = 140. Participants received a questionnaire and a map to draw their commuting route on. The main findings of the thesis were, firstly, that the map-based method could function as a criterion method for active commuting distance measurements and, secondly, that four assessed distance measurement methods – straight-line distance, GIS, GPS and self-report – differed significantly from the criterion method. Therefore, we recommend the use of correction factors to compensate for the systematic over- and underestimations. We also found three distinctly different modality groups in both men and women with different behaviours in commuting distance, duration and trip frequency. These groups were commuters who exclusively walk or bicycle the whole way to work, and dual mode commuters who switch between walking and cycling. These mode groups accrued different amounts of activity time for commuting. Through active commuting per se, the median pedestrian and dual mode commuters met or were close to the recommended physical activity level of 150 minutes per week during most months of the year, whereas the single mode cyclists did so only during the summer half of the year. / FAAP
187

Duurverskynsels by enkelvoudige nasale en komplekse nasaalverbindings in Xhosa

Olivier, Iolanda 03 1900 (has links)
Thesis (MA)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: In this assignment durational features in singular nasals and complex nasal combinations in Xhosa are studied. The focus is on durational differences between single nasals, nasals in combination with consonants and nasal combinations featuring a morpheme boundary. Nouns were selected with these INCI-combinations in various syllable positions in a word. Data from one mother-tongue speaker were analysed and statistically processed and internally compared. It was found that the duration of a singular /m/ and /n/ preceding a morpheme boundary was longer than the corresponding nasal in a final syllable without an intervening morpheme boundary. When an obstruent appears in conjunction with a labial and alveolar nasal, the total duration of these INCI-combinations are longer than those of the singular /m/ and /n/. The presence of a morpheme boundary after complex nasals seemingly has no influence on the duration of the nasal or on the rest of the segments in the syllable. The duration of the syllabic /m/ is longer than that of the singular labial /m/. As secondary findings sequential aspects of nasals are discussed. In this study theoretical arguments are offered where possible in support of the above mentioned results. / AFRIKAANSE OPSOMMING: In hierdie werkstuk word duurverskynsels by enkelvoudige nasale en komplekse nasaalverbindings in Xhosa bestudeer. Daar word gefokus op die duurverskillle tussen enkelvoudige nasale, nasale in kombinasie met konsonante en nasaalverbindings waar 'n morfeemgrens voorkom. Naamwoorde is gesoek met die INK/-kombinasies in die laaste sillabeposisie, voorfinale en enige sillabeposisie vorentoe in die woord. Die data van een moedertaalspreker is ontleed en statisties verwerk. Die resultate hiervan is ook onderling met mekaar vergelyk. Daar is onder meer bevind dat die duur van 'n enkelvoudige /m/ en /n/ relatief langer is voor 'n morfeemgrens as die ooreenstemmende nasaal in 'n finale sillabe sonder 'n morfeemgrens. Wanneer 'n stopklank saam met 'n labiale en alveolere nasaal verskyn, is die totale duur van die INK/-kombinasies langer as die enkelvoudige /m/ en /n/ s'n. Die teenwoordigheid van 'n morfeemgrens na komplekse nasale het skynbaar geen invloed op die duur van die nasaal en of die res van die segmente in die sillabe nie. Die sillabiese /m/ se duur is langer as die enkelvoudige labiale /m/. In die sekondere bevindinge word sekere opeenvolgings van die nasaal bespreek. In hierdie studie word, waar moontlik, sekere teoretiese argumente aangebied vir onder meer bogenoemde resultate.
188

HYSTERESIS IN REPOLARIZATION OF CARDIAC ACTION POTENTIALS: EFFECTS OF SPATIAL HETEROGENEITY AND SLOW REPOLARIZATION CURRENTS

Jing, Linyuan 01 January 2013 (has links)
Repolarization alternans, i.e. beat-to-beat variation of repolarization of action potential, is proposed as a predictor of life-threatening arrhythmias. Restitution relates repolarization duration with its previous relaxation time, i.e. diatstolic interval (DI), and is considered a dominant mechanism for alternans. Previously, we observed that different repolarization durations at the same DI during decelerating and accelerating pacing, i.e. restitution displays hysteresis, which is a measure of “cardiac memory”. Objective of the current study was to investigate in the pig 1) the mechanism for a previously observed hysteresis type phenomenon, where alternans, once started at higher heart rate, persists even when heart rate decreases below its initiating rate, 2) regional differences in expression of hysteresis, i.e. memory in restitution in the heart, and 3) changes in restitution and memory during manipulation of an important repolarization current, the slow delayed rectifier, IKs. Action potentials were recorded in pig ventricular tissues using microelectrodes. Regional differences were explored in endocardial and epicardial tissues from both ventricles. DIs were explicitly controlled in real time to separate restitution mechanism from non-restitution related effects. Stepwise protocols were used to explore the existence in hysteresis in alternans threshold, where DIs were held constant for each step and progressively decreased and then increased. Quantification of cardiac memory was achieved by sinusoidally changing DI protocols, which were used to investigate memory changes among myocytes from different regions of the heart and during IKs manipulation. Results show that during stepwise protocol, hysteresis in alternans still existed, which indicates that restitution is not the only mechanism underlying the hysteresis. When comparing hysteresis obtained from sinusoidally oscillatory DIs among different regions, results show memory is expressed differently with endocardium expressing the most and epicardium the least memory. This provides important implications about the location where arrhythmia would initiate. Results also show that measures for hysteresis loops obtained by sinusoidal DI protocols decreased (increased) after enhancement (attenuation) of IKs, suggesting decreased (increased) hysteresis, i.e. memory in restitution. This effect needs to be considered during drug development.
189

The Rational Design of Security Institutions: Effects of Institutional Design on Institutional Performance

Tandon, Aakriti A. January 2012 (has links)
Based on the assumption that security institutions are designed rationally, I study the variations in design schemes and their possible effects on institutional performance. Military alliances vary with respect to their membership size, level of security obligations undertaken by the allies, incorporation of non security clauses such as economic agreements, level of institutionalization, specified duration of existence, as well as the conditions under and reasons for which they are formed. This dissertation studies the effects of above mentioned design features on the probability of security alliances expanding their scope by addressing non-security agreements such as free trade agreements and conflict management clauses. I find support for the argument that states include economic agreements within a military alliance as a means to bolster the credibility of an otherwise weak security alliance. Results indicate that allies facing high levels of external threat and low levels of intra alliance cohesion are more likely to include conflict management provisions in the alliance. Finally, I conduct a systematic study of the possible effects of variation in structural design on the durability of an alliance. I find that design features that increase the costs of breaking the alliance increase the duration of an alliance.
190

Topinambo (Helianthus tuberosus l.) gumbų kokybės kitimas laikymo metu / Jerusalem artichoke (Helianthus tuberosus L.) tubers quality changes during storage

Kelpšienė, Rūta 09 June 2010 (has links)
Darbo tikslas – ištirti topinambo (Helianthus tuberosus L.) gumbų kokybės kitimą laikymo metu. 2009 metais tyrimams skirti topinambų gumbai išauginti Kauno rajone Babtuose, Lietuvos sodininkystės ir daržininkystės institute. Dviejų selekcinių linijų 05-1 bei 05-7 topinambų gumbai pasodinti gegužės pirmąjį dešimtadienį, nukasti lapkričio mėnesį. Topinambų gumbai po nukasimo 3 savaites laikyti +10oC temperatūros patalpoje žaizdų užgyjimui. Visi mėginiai buvo laikyti 20 savaičių durpėse (4 pakartojimais po 8 kg) šaldymo spintose KX – Ю su automatiniu temperatūros reguliatoriumi, esant 2ºC temperatūrai ir 90 - 95 % santykiniam oro drėgniui. Standartiniais metodais žaliavoje nustatyti sausųjų medžiagų, tirpių sausųjų medžiagų, žalios ląstelienos, žaliųjų proteinų bei amino rūgščių kiekiai. Tyrimų duomenų vidurkiai bei standartiniai nuokrypiai apskaičiuoti „Microsoft Excel“ programa, koreliacinio ryšio analizė – „STAT for EXCEL“ programa (paketas Selekcija, AGROLITPA, 2004. P. Tarakanovas). Nustatyta, kad po 5 mėnesių sausųjų medžiagų kiekis 05-7 selekcinės linijos gumbuose buvo 2,19 % didesnis nei 05-1 selekcinės linijos gumbuose. Po 5 laikymo mėnesių esminiai didesnės tirpių sausųjų medžiagų, žalios ląstelienos kiekių netektys (atitinkamai 1,95 % ir 0,85 %) nustatytos 05-1 selekcinės linijos topinambų gumbuose. Visų tyrimų laikotarpiu daugiausiai abiejų selekcinių linijų laikomuose topinambų gumbuose buvo nustatyta nepakeičiamosios amino rūgšties arginino ir pakeičiamosios... [toliau žr. visą tekstą] / Aim of work – to research the quality changes of Jerusalem artichoke during storageing. In 2009 the Jerusaelem artichoke tubers were grown in Kaunas distric Babtai, Lithuanian institute of gardening and olericulture. Two selection Jerusalem artichoke lines 05-1 and 05-7 were planted in the begining of may and harvested in November. After that they were kept in temperature +10 for 3 weeks in order to treat the slash. The all examples were put in automatically adjusting fridge KX-10 for 20 weeks (8 kg in four replications), where the temperature was 0 – 2 Celsius and the relative humidity 90 – 95 %. The chemical composition was analysed using standart methods: amount of dry matters, melting dry materials, crude proteins, dietary fiber, amino acids. The research data average and standart deviations was calculated using Microsoft Excel program, correlation analyses – „STAT for EXCEL“ program (Selection, Agrolitpa, 2004. P. Tarakanovas). After five months of storage the amount of dry matters in 05-7 selection line tubers was 2,19 % bigger, than in 05-1 selection line tubers. The bigger melting dry materials, diatary fiber losses (accordingly 1,95% and 0,85%) after five months of storage were determine in 05-1 selection line tubers. The biggest amount of inalterable amino acids arginine and glutamine and the smallest amount of alterable amino acids methionine and proline were determine in both of selection line tubers. After five months of storage the quality of 05-7 selection... [to full text]

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