Abstrakt: Inom vården används olika undersökningsmetoder för att kunna utvärdera hjärtats funktion. Elektrokardiografi (EKG) är en av de metoderna. EKG har många fördelar exempelvis är metoden tillgänglig, billig, riskfri och icke-invasiv. Vid vilo-EKG placeras tio elektroder på bestämda positioner på kroppen vilka ger upphov till 12 avledningar. Avledningarna indelas i två grupper: bröstavledningar och extremitetavledningar. Studiens syfte var att undersöka närmare om det finns skillnader som påverkar bedömningen av EKG:et i P- vågor, QRS- komplex och hjärtats elektriska axel (QRS el-axel) i extremitetavledningar mellan standardkoppling och två andra omkopplingar. Trettio frivilliga deltagare inkluderades i denna studie. För samtliga deltagare registrerades tre EKG:n. I det första EKG:et kopplades extremitetselektroderna enligt standardkopplingen. I det andra EKG:et kopplades armelektroder på höger och vänstra överarmar, vänster benelektroden kopplades på lårbenet. Det tredje EKG:et kopplades enligt Mason- Liker, förutom att höger benelektrod inte omplacerades. Vid alla tre EKG:na placerades bröstelektroderna enligt standardkopplingen. Förändringar i duration, amplitud, och QRS el-axel mellan dessa EKG:n undersöktes. Resultaten av studien visade att det inte fanns någon signifikant skillnad mellan dessa kopplingar i duration och amplitud i QRS-komplexen. Inte heller i durationen på P-vågen. Däremot påvisades en signifikant skillnad i QRS el-axel samt i amplitud på P-vågen för den ena omkopplingen.

This study presents detailed phonetic and acoustic analyses of the speech characteristics of two new cases of Foreign Accent Syndrome (FAS). Participants include a 48-year-old female who began speaking with an "Eastern European" accent following a traumatic brain injury, and a 45-year-old male who presented with a "British" accent following a subcortical cerebral vascular accident (CVA). Identical samples of the participants' pre- and post-morbid speech were obtained, thus affording a new level of control in the study of Foreign Accent Syndrome. The speech tasks consisted of oral readings of the Grandfather Passage and 18 real words comprised of the stop consonants /p/, /t/, /k/, /b/, /d/, /g/ combined with the peripheral vowels /i/, /a/ and /u/ and ending in a voiceless stop. Computer-based acoustic measures included: 1) voice onset time (VOT), 2) vowel durations, 3) whole word durations, 4) first, second and third formant frequencies, and 5) fundamental frequency. Formant frequencies were measured at three points in the vowel duration: a) 20%, b) 50%, and c) 80% to assess differences in vowel 'onglides' and 'offglides'. The phonetic analysis provided perceptual identification of the major phonetic features associated with the foreign quality of participant's FAS speech, while acoustic measures allowed precise quantification of these features. Results indicated evidence of backing of consonant and vowel productions for both participants. The implications for future research and clinical applications are also considered.

Doctor of Philosophy / Department of Animal Sciences and Industry / Michael D. Tokach / Five experiments were performed to determine the influence of creep feeding on individual consumption characteristics and growth performance of neonatal and weanling pigs. These evaluated the effects of lactation feed intake and creep feeding (n = 84 litters; Exp. 1), creep feeding duration (n = 54 litters; Exp. 2), creep feeder design and feed accessibility (n = 54 litters; Exp. 3), organoleptic properties of the creep feed (n = 50 litters; Exp. 4) and creep diet complexity (n = 96 litters; Exp. 5). In summary, creep feeding did not affect preweaning gains and weaning weights of pigs weaned at 3 weeks of age. Creep feeding for 18 d did not influence sow performance. However, creep feeding tended to improve litter weaning weights due to improved survivability. Creep feed consumption was related to piglet maturity rather than the induction of creep feeding. In both experimental and field conditions, pigs that consumed creep feed (eaters) had greater post-weaning feed intake and daily gains compared to non-eaters (pigs that did not consume creep feed) and non-creep fed pigs. This led to improvements in pig weight uniformity and reduction of the severity of post-weaning lag. These benefits were achieved regardless of weaning weight, the complexity of the creep diet, and the duration of creep feeding. The proportion of eaters of creep feed in whole litters can be manipulated. Longer duration of creep feeding increased the proportion of eaters. A rotary creep feeder with a hopper created the most eaters with the lowest creep feed disappearance. Creep diet complexity had the greatest effect in increasing the proportion of pigs consuming creep feed. On the other hand, low feed intake of lactating sows and adding feed flavors to the creep feed did not affect creep feed consumption and the proportion of pigs consuming creep feed. Therefore, creep feeding that focuses in encouraging more suckling piglets to eat is beneficial in producing weanling pigs that are better adapted to weaning, which improves post-weaning performance.

Thesis (PhD (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / Although the Class D topology offers several advantages, its use in audio amplification has previously been limited by the lack of competitiveness in fidelity compared to its linear counterparts. During the past decade, technological advances in semiconductor technology have awakened new interest since competitive levels of distortion could now be achieved. The output stage of such an amplifier is the primary limiting factor in its performance. In this dissertation, four non-ideal effects existing in this stage are identified and mathematically analysed. The analytical analysis makes use of a well-established mathematical model, based on the double Fourier series method, to model the imperfections introduced into a naturally sampled pulsewidth modulated waveform. The analysis is complemented by simulation using a strategy based on Newton’s numerical method. The theory is verified by a comparison between the analytical-, simulated- and experimental results.

在過去文獻中多有討論遷徙行為者，但少有對家戶的居住時間進行分析，本研究首先檢視自有者與租賃者之居住時間，其次為瞭解家戶對實質住宅的經濟需求較大，還是對已建立的社會關係網絡需求較大，提出居住時間的時間相依性問題，即隨著居住時間的增加，家戶會因為對住宅需求改變而愈容易遷徙？還是在累積惰性下愈不易遷徙？最後則是探討家戶居住時間的影響因素，藉由不同的住宅與家戶特徵來瞭解家戶可能的居住時間，以作為住宅遷徙、流動性及其他住宅政策分析之參考。 本研究在實證方法上採取存活分析法，並利用華人家庭動態資料庫的橫斷面跨時資料進行研究。實證結果顯示，自有者的存活函數明顯大於租賃者，且自有家戶之居住時間為租賃家戶的3.11倍。另外，家戶遷徙機率具有正時間相依性，反應出家戶隨著居住時間的增加，遷徙機率會增加，然而自有家戶模型的遷徙機率卻呈現負時間相依性。居住時間影響因素實證結果，每人坪數較大，居住時間會較短，而年齡愈大與居住人數愈多者，居住時間會較長。 / Although there are lots of studies exploring migration, few of them focus on analysis household duration of residence. Duration of residence is an important source of information for a variety of private and pubic decisions and for the understanding of various social and economic phenomena. This study makes a residence duration comparison between owners and tenants. Due to cumulative stress and inertia, moving probability will be increased or decreased. We attempt to describe the duration of residence is positive or negative time dependent. This study also provides the evidence that house and household characteristics determine the duration of residence. This empirical study employs the survival analysis and uses the data from Panel Study of Family Dynamics. The result indicates that the survival function of owners is larger than of tenant. Duration of owner residence is 3.11 times longer than that of tenants. Generally, household moving probability is positive while the owner’s is negative. Research finding further reveals that ping per person is negatively related to residence duration. Age and household size are positively related to residence duration.

Disertacijoje nagrinėjamos dvi iki šiol netyrinėtos problemos: 1. Lietuvių kalbos garsų trukmių prognozavimo modelių kūrimas Iki šiol visi darbai, kuriuose yra nagrinėjamos lietuvių kalbos garsų trukmės, yra atlikti kalbininkų, tačiau šie tyrimai yra daugiau aprašomosios statistikos pobūdžio ir apsiriboja pavienių požymių įtakos garso trukmei analize. Šiame darbe, mašininio mokymo algoritmo pagalba, požymių įtaka garsų trukmei yra išmokstama iš duomenų ir užrašoma sprendimo medžio pavidalu. 2. Nuo kalbos nepriklausomų garsų trukmių prognozavimo modelių kūrimo metodas, naudojant didelės apimties daugelio, kalbėtojų automatiškai, anotuotą garsyną. Dėl skirtingų kalbėtojų tarties specifikos ir dėl automatinio anotavimo netikslumų, kuriant garsų trukmės modelius visame pasaulyje yra apsiribojama vieno kalbėtojo ekspertų anotuotais nedidelės apimties garsynais. Darbe pasiūlyti skirtingų kalbėtojų tarties ypatybių normalizavimo ir garsyno duomenų triukšmo atmetimo algoritmai leidžia garsų trukmių modelių kūrimui naudoti didelės apimties, daugelio kalbėtojų automatiškai anotuotus garsynus. Darbo metu atliktas audicinis tyrimas, kurio pagalba parodoma, kad šnekos signalą sudarančių garsų trukmės turi įtakos klausytojų/respondentų suvokiamam šnekos signalo natūralumui; kontekstinės informacijos panaudojimas garsų trukmių prognozavimo uždavinio sprendime yra svarbus faktorius įtakojantis sintezuotos šnekos natūralumą; natūralaus šnekos signalo atžvilgiu, geriausiai vertinamas yra... [toliau žr. visą tekstą] / Two heretofore unanalyzed aspects are addressed in this dissertation: 1. Building a model capable of predicting phone duration of Lithuanian. All existing investigations of phone durations of Lithuanian were performed by linguists. Usually these investigations are the kind of exploratory statistics and are limited to a single factor, affecting phone duration, analysis. Phone duration dependencies on contextual factors were estimated and written in explicit form (decision tree) in this work by means of machine learning method. 2. Construction of language independent method for creating phone duration models using very large, multi-speaker, automatically annotated speech corpus. Most of the researchers worldwide use speech corpus that are: relatively small scale, single speaker, manually annotated or at least validated by experts. Usually the referred reasons are: using multi-speaker speech corpora is inappropriate because different speakers have different pronunciation manners and speak in different speech rate; automatically annotated corpuses lack accuracy. The created method for phone duration modeling enables the use of such corpus. The main components of the created method are: the reduction of noisy data in speech corpus; normalization of speaker specific phone durations by using phone type clustering. The performed listening tests of synthesized speech, showed that: the perceived naturalness is affected by the underlying phones durations; The use of contextual... [to full text]

Optokinetic nystagmus (OKN) is a fundamental gaze-stabilising response in which eye movements attempt to compensate for the retinal slip caused by self-motion. The OKN response consists of a slow following movement made in the direction of stimulus motion interrupted by fast eye movements that are primarily made in the opposite direction. The timing and amplitude of these slow phases and quick phases are notably variable, but this variability is poorly understood. In this study I performed principal component analysis on OKN parameters in order to investigate how the eigenvectors and eigenvalues of the underlying components contribute to the correlation between OKN parameters over time. I found three categories of principal components that could explain the variance within each cycle of OKN, and only parameters from within a single cycle contributed highly to any given component. Differences found in the correlation matrices of OKN parameters appear to reflect changes in the eigenvalues of components, while eigenvectors remain predominantly similar across participants, and trials. I have developed a linear and stochastic model of OKN based on these results and demonstrated that OKN can be described as a 1st order Markov process, with three sources of noise affecting SP velocity, QP triggering, and QP amplitude. I have used this model to make some important predictions about the optokinetic reflex: the transient response of SP velocity, the existence of signal dependent noise in the system, the target position of QPs, and the threshold at which QPs are generated. Finally, I investigate whether the significant variability within OKN may represent adaptive control of explicit and implicit parameters. iii

Cardiovascular disease is the leading cause of death in the United States. Chronic short sleep duration is also a significant public health problem and has been linked to several markers and outcomes of cardiovascular disease. To date, inconsistency of assessments of sleep duration and insufficiency, use of covariates, and cardiovascular disease measurement across studies limits strong conclusions about the relationship between sleep duration, sleep insufficiency, and cardiovascular disease. The current study examined the association between sleep duration, sleep insufficiency, and a marker of preclinical coronary heart disease (i.e., carotid intima-media thickness) in a community sample using a cross-sectional design. Some evidence for a relationship between sleep duration and cIMT was found, with longer sleep duration predicting higher cIMT in some segments. Additionally, the interaction between sleep duration and sleep insufficiency was significant. However, neither of these effects were significant after adjusting for age and in some cases race/ethnicity, suggesting demographics may explain this association. Actigraphy and sleep diary duration assessments demonstrated significantly different correlations with cIMT in some segments, suggesting the nature of the assessment method may impact the strength or direction of the relationship between sleep duration and cIMT. Limitations and future directions are discussed.

In most developing countries, housing finance and mortgage lending are undergoing changes driven by financial deregulation policies, which include interest rate decontrol and privatization. In this study, we analyze detailed residential mortgage data from housing finance institutions (HFIs) in Kenya, to determine the impact of deregulation on loan performance. Using a hazard model, we find that interest rates, real Gross Domestic Product (GDP), exchange rate, and deregulation are significant in explaining the hazard of mortgage delinquency. We use a before and after deregulation framework to analyze the influence of deregulation on the probability of mortgage delinquency, and find that the number of delinquent loans increased after deregulation, the duration of loans from time of loan origination to time of delinquency decreased, and that loan repayment was also faster after deregulation. The study concludes that deregulation increased both the probability of delinquency as well as the probability of loan prepayment in Kenya. Our interpretation of the results is that, borrowers reacted to increasing interest rates, trigger events, and availability of cheaper funds elsewhere, while lenders reacted to increased competition introduced by deregulation by adopting more flexible credit risk analysis as well as teaser rates to attract demand. Given the scarcity of literature relating to mortgage finance in sub-Sahara Africa, this study provides valuable insight into the current lending environment, feasibility of future lending, and includes suggestions for improvement.

The subject of this thesis is perceptual sensitivity with respect to subtle frequency-based and temporal manipulations in speech, music and mixed stimuli. We hypothesize that an individual's sensitivity to variation in all three types of stimuli should be similar (i.e. a correlation should exist), seeing that findings in evolutionary biology, neurosciences, psy- chology and experimental phonetics are pointing towards a relatively strong link between the mechanisms of perception in speech and music. Our listening experiment revealed mostly intermediate correlations; additionally, we argue that by employing syntactically less complicated stimuli, which would target specifically fundamental sensitivity without requiring a complex syntactic analysis in parallel, even more robust correlations could be obtained. While the influence of prior formal linguistic education on performance in the test was negligible, the influence of musical experience was considerable, which lends further support to the idea of simplifying especially the music stimuli in future research. Key words: music, speech, perception, sensitivity, correlation