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Yes / A low concentration poly(acrylamide) sensor has been developed which uses the segmental mobility of another polymer probe with a covalently attached fluorescent marker. Interpolymer complexation with poly(acrylic acid) leads to reduced segmental mobility which can be used to determine the concentration of polymer in solution. This technique could be useful in detecting the runoff of polymer dispersants and flocculants in fresh water supplies following water purification processes. / Funding for the research was kindly provided by the Engineering and Physical Sciences Research Council (EPSRC).

Yes / Thermal desolvation of poly(N‐isopropylacrylamide) (PNIPAM) in the presence of a low concentration of gold nanoparticles incorporates the nanoparticles resulting in suspended aggregates. By covalently incorporating <1% acenaphthylene into the polymerization feed this copolymer is enabled to be used as a model to study the segmental mobility of the PNIPAM backbone in response to gold nanoparticles both below and above the desolvation temperature, showing that there is a physical conformational rearrangement of the soluble polymer at ultralow nanoparticle loadings, indicating low affinity interactions with the nanoparticles. Thermal desolvation is capable of extracting >99.9% of the nanoparticles from their solutions and hence demonstrates that poly(N‐isopropylacrylamide) can act as an excellent scrubbing system to remove metallic nanomaterial pollutants from solution. / Science Foundation Ireland's ETS. Grant Number: 11/W.I/12085; MRC. Grant Number: MR/N501888/2

Esta dissertação trata da queda de sílaba em limite de palavra no falar da cidade paulista de Capivari, observando-se em quais contextos esse processo fonológico pode ocorrer e em quais nunca ocorre. Para realizar essa análise, são considerados três níveis fonológicos, quais sejam: segmental, prosódico e métrico. A queda de sílaba é tratada como dois tipos distintos de redução fonológica: na elisão silábica, há dessemelhança entre as consoantes das sílabas envolvidas; com relação à haplologia, as consoantes das sílabas são iguais ou semelhantes ? a diferença entre elas está apenas no traço [sonoridade]. Pôde-se constatar, pela análise de contextos segmentais, que tanto a elisão silábica quanto a haplologia são processos regidos pelas mesmas regras, uma vez que ambos os processos se dão no mesmo ponto de consoante para que possa haver efetiva queda de sílaba. E, da mesma forma, esses processos fonológicos podem ocorrer em qualquer nível da hierarquia prosódica. Isso evidencia que a elisão silábica e a haplologia são de fato o mesmo processo fonológico. Finalmente, a análise métrica aponta as mesmas propriedades para a elisão silábica e para a haplologia no que diz respeito ao uso desses processos para otimizações rítmicas / This work deals with syllable deletion in word boundary in Capivari speech, a city from the countryside of São Paulo state. It was checked in which contexts this phonological process can occur and in which it can never occur. To fulfill this analysis three phonological levels were considered: segmental, prosodic and metrical. Syllable deletion is dealt as two distinct types of phonological reduction: in syllable drop, the syllable\'s consonants are distinct from each other; in haplology, the consonants are equal or alike - the difference between them is only the feature [sonority]. By the analysis of segmental contexts, it has been proved that both syllable drop and haplology are types of processes which are governed by the same rules, for both of them must have the same consonant place node, so that there can be in fact syllable deletion. In the same way, both the phonological processes may occur in any prosodic level from which it is evident that syllable drop and haplology are actually the same phonological process. To verify if both the processes are rhythmically used in the same way it has been pointed out by metrical analysis that syllable drop and haplology present the same properties as regards to optmization

Esta dissertação trata da queda de sílaba em limite de palavra no falar da cidade paulista de Capivari, observando-se em quais contextos esse processo fonológico pode ocorrer e em quais nunca ocorre. Para realizar essa análise, são considerados três níveis fonológicos, quais sejam: segmental, prosódico e métrico. A queda de sílaba é tratada como dois tipos distintos de redução fonológica: na elisão silábica, há dessemelhança entre as consoantes das sílabas envolvidas; com relação à haplologia, as consoantes das sílabas são iguais ou semelhantes ? a diferença entre elas está apenas no traço [sonoridade]. Pôde-se constatar, pela análise de contextos segmentais, que tanto a elisão silábica quanto a haplologia são processos regidos pelas mesmas regras, uma vez que ambos os processos se dão no mesmo ponto de consoante para que possa haver efetiva queda de sílaba. E, da mesma forma, esses processos fonológicos podem ocorrer em qualquer nível da hierarquia prosódica. Isso evidencia que a elisão silábica e a haplologia são de fato o mesmo processo fonológico. Finalmente, a análise métrica aponta as mesmas propriedades para a elisão silábica e para a haplologia no que diz respeito ao uso desses processos para otimizações rítmicas / This work deals with syllable deletion in word boundary in Capivari speech, a city from the countryside of São Paulo state. It was checked in which contexts this phonological process can occur and in which it can never occur. To fulfill this analysis three phonological levels were considered: segmental, prosodic and metrical. Syllable deletion is dealt as two distinct types of phonological reduction: in syllable drop, the syllable\'s consonants are distinct from each other; in haplology, the consonants are equal or alike - the difference between them is only the feature [sonority]. By the analysis of segmental contexts, it has been proved that both syllable drop and haplology are types of processes which are governed by the same rules, for both of them must have the same consonant place node, so that there can be in fact syllable deletion. In the same way, both the phonological processes may occur in any prosodic level from which it is evident that syllable drop and haplology are actually the same phonological process. To verify if both the processes are rhythmically used in the same way it has been pointed out by metrical analysis that syllable drop and haplology present the same properties as regards to optmization

The purpose of this work is to measure the degree of intelligibility of native and non-native English speech as well as analyse the major sources of intelligibility failure when speakers of these varieties of English interact. British and American English (henceforth BrE and AmE) and Cameroon English (hereafter CamE) are used as a case study with focus on segmental and supra segmental features. The study was motivated by a number of concerns, several of which are more prominent: First, it was motivated by the trepidation scholars like Gimson (1965, 1980); Prator (1968); etc. nursed that the unprecedented spread of English across the globe and the emergence of non-native varieties would cause English to disintegrate into mutually unintelligible languages, in the way Romance languages devolved from their Latin ancestor. The second motivation was that previous researchers (Bansal 1969, Tiffen 1974) on intelligibility have often concentrated their efforts on the traditional approach, which sees intelligibility from a one-sided perspective. To them, the non-native varieties of English are deficient and not different varieties from the native varieties. They were seen as substandard, incorrect, and unintelligible and thus needed remediation at all costs. The native varieties were seen as prestigious, correct, intelligible and the sole norm that must be emulated by non-native English speakers. In this way any interaction between a native speaker and a non-native speaker should be characterised by the non-native speaker making all the efforts to be understood as well as to understand the native English-speaking partner. This explains in large part why these researchers concentrated on measuring the intelligibility of non-native speech to native speakers and never vice versa. It was as if it was treasonable to measure the intelligibility of native speech to non-native speakers. Even if some researchers managed to do this, the comments that followed such data still showed that the aim was not to test the intelligibility of native speakers but to find out how efficient the non-native speakers were in understanding the native speaker. Another aim could also be to reinforce the teaching of the native norm, which was seen as “correct” against non-native features, which were seen as “incorrect”, to measuring intelligibility. While accepting that these studies reflected the conventional wisdom of the time, this study aims to move the debate forward by looking at intelligibility from a two-sided perspective. It sees communication between speakers of different varieties as a game of give and take, where both participants “tune in” to make the process successful rather than one participant being obliged to make all the efforts because s/he speaks a new English variety. That explains why we are testing not only the intelligibility of non-native speakers to native speakers but also native speakers to non-native speakers. / Gegenstand der vorgelegten Promotionsarbeit ist die Untersuchung der gegenseitigen Verständlichkeit von muttersprachlichem und nicht-muttersprachlichem Englisch. Im besonderen werden die Hauptquellen und Ursachen des Scheiterns von Verständlichkeit in einer empirischen Studie bestimmt, klassifiziert und analysiert. Die Untersuchung wird exemplarisch anhand des Kamerunischen Englisch einerseits und des Britischen und Amerikanischen Englisch anderseits vorgenommen. Motiviert ist diese Arbeit vor allem durch folgende Punkte. Erstens bedarf es der Auseinandersetzung mit den durch eine Reihe von Autoren geäußerten Befürchtungen (z.B. Gimson 1965, 1980 und Prator 1968), daß die Herausbildung und Entwicklung neuer Varianten des Englischen letztlich zu einer Auflösung des Englischen in gegenseitig nicht mehr verständliche Sprachen führt, ein Prozeß, wie er sich historisch bei der Entstehung der romanischen Sprachen aus dem Lateinischen vollzog. Derartige Befürchtungen werden genährt durch die bisher ohnegleichen fortschreitende Verbreitung des Englischen über den gesamten Globus. Hier ergibt sich die dringende Notwendigkeit vergleichender Studien zur gegenseitigen Verständlichkeit zwischen den bestehenden Varianten. Zweitens folgen die meisten zu diesem Thema vorliegenden Untersuchungen im wesentlichen einer traditionellen, überkommenen Grundperspektive: die nicht-muttersprachlichen Varianten des Englischen werden als „abweichend“ bzw. sogar „defizitär“ aus Sicht der muttersprachlichen betrachtet, nicht aber als eigenständige Sprachformen (z.B. Bansal 1969; Tiffen 1974). Dies führt nach Auffassung des Autors zu einer einseitigen Betrachtung und Bewertung. Im besonderen wird in der sprachlichen Interaktion bei einem solchen Zugang die Last zu verstehen und für den Kommunikationspartner verständlich zu sein einseitig dem nicht-muttersprachlichen Sprecher übertragen. Auf diesem Hintergrund untersuchen die vorliegenden Studien anderer Autoren primär die Verständlichkeit nicht-muttersprachlicher Sprachformen für den muttersprachlichen Sprecher, nicht jedoch die umgekehrte Konstellation. Wenn die umgekehrte Perspektive überhaupt berücksichtigt wird, so zeigen die Kommentare, daß nicht die Verständlichkeit muttersprachlicher Sprecher für den Nichtmuttersprachler eigentliches Ziel und Gegenstand der Untersuchung war, sondern vielmehr die Frage, wie effizient sich Nichtmuttersprachler beim Verstehen muttersprachlicher Äußerungen zeigten. Des weiteren stehen diese Studien oft im Kontext des Bestrebens, im institutionalisierten Spracherwerb die muttersprachlichen Normen gegen die nicht-muttersprachlichen Merkmale durchzusetzen, die als „nicht korrekt“ angesehen werden. Diese Positionen, der zugrundeliegende Zugang und die einseitige Ausrichtung bedürfen einer kritischen Auseinandersetzung.

Sasol Limited experiences extremely high particulate fouling rates inside shell-and-tube heat exchangers that utilize process cooling water. The water and foulants are obtained from various natural and process sources and have irregular fluid properties. The fouling eventually obstructs flow on the shell side of the heat exchanger to such an extent that the tube bundles have to be replaced every nine months. Sasol requested that certain aspects of this issue be addressed. To better understand the problem, the effects of various tube and baffle configurations on the sedimentation rate in a shell-and-tube heat exchanger were numerically investigated. Single-segmental, double-segmental and disc-and-doughnut baffle configurations, in combination with square and rotated triangular tube configurations, were simulated by using the CFD software package, STAR-CCM+. In total, six configurations were investigated. The solution methodology was divided into two parts. Firstly, steady-state solutions of the six configurations were used to identify the best performing model in terms of large areas with high velocity flow. The results identified both single-segmental baffle configurations to have the best performance. Secondly, transient multiphase simulations were conducted to investigate the sedimentation characteristics of the two single-segmental baffle configurations. It was established that the current state of available technology cannot adequately solve the detailed simulations in a reasonable amount of time and results could only be obtained for a time period of a few seconds. By simulating the flow fields for various geometries in steady-state conditions, many of the observations and findings of literature were verified. The single-segmental baffle configurations have higher pressure drops than double-segmental and disc-and-doughnut configurations. In similar fashion, the rotated triangular tube configuration has a higher pressure drop than the square arrangement. The single-segmental configurations have on average higher flow velocities and reduced cross-flow mass flow fractions. It was concluded from this study that the single-segmental baffle with rotated triangular tube configuration had the best steady-state performance. Some results were extracted from the transient multiphase simulations. The transient multiphase flow simulation of the single-segmental baffle configurations showed larger concentrations of stagnant sediment for the rotated triangular tube configuration versus larger concentrations of suspended/flowing sediment in the square tube configuration. This result was offset by the observation that the downstream movement of sediment was quicker for the rotated triangular tube configuration. No definitive results could be obtained, but from the available results, it can be concluded that the configuration currently implemented at Sasol is best suited to handle sedimentation. This needs to be verified in future studies by using advanced computational resources and experimental results. / Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013

Sasol Limited experiences extremely high particulate fouling rates inside shell-and-tube heat exchangers that utilize process cooling water. The water and foulants are obtained from various natural and process sources and have irregular fluid properties. The fouling eventually obstructs flow on the shell side of the heat exchanger to such an extent that the tube bundles have to be replaced every nine months. Sasol requested that certain aspects of this issue be addressed. To better understand the problem, the effects of various tube and baffle configurations on the sedimentation rate in a shell-and-tube heat exchanger were numerically investigated. Single-segmental, double-segmental and disc-and-doughnut baffle configurations, in combination with square and rotated triangular tube configurations, were simulated by using the CFD software package, STAR-CCM+. In total, six configurations were investigated. The solution methodology was divided into two parts. Firstly, steady-state solutions of the six configurations were used to identify the best performing model in terms of large areas with high velocity flow. The results identified both single-segmental baffle configurations to have the best performance. Secondly, transient multiphase simulations were conducted to investigate the sedimentation characteristics of the two single-segmental baffle configurations. It was established that the current state of available technology cannot adequately solve the detailed simulations in a reasonable amount of time and results could only be obtained for a time period of a few seconds. By simulating the flow fields for various geometries in steady-state conditions, many of the observations and findings of literature were verified. The single-segmental baffle configurations have higher pressure drops than double-segmental and disc-and-doughnut configurations. In similar fashion, the rotated triangular tube configuration has a higher pressure drop than the square arrangement. The single-segmental configurations have on average higher flow velocities and reduced cross-flow mass flow fractions. It was concluded from this study that the single-segmental baffle with rotated triangular tube configuration had the best steady-state performance. Some results were extracted from the transient multiphase simulations. The transient multiphase flow simulation of the single-segmental baffle configurations showed larger concentrations of stagnant sediment for the rotated triangular tube configuration versus larger concentrations of suspended/flowing sediment in the square tube configuration. This result was offset by the observation that the downstream movement of sediment was quicker for the rotated triangular tube configuration. No definitive results could be obtained, but from the available results, it can be concluded that the configuration currently implemented at Sasol is best suited to handle sedimentation. This needs to be verified in future studies by using advanced computational resources and experimental results. / Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013

<p>Oral 111-Indium-DTPA colonic scintigraphy was used to assess segmental transit in 23 patients with slow transit constipation (STC) and 13 controls. The transit time did not differ between patients and controls in the right colon, whereas the patients had a consistent delay from the transverse colon and distally (<i>P</i><0.05–0.001). Two individual patients had a delay in the right colon.</p><p>Twenty-eight patients underwent a left- (n=26) or a right (n=2) hemicolectomy for STC, after evaluation including colonic scintigraphy. Twenty-three patients (80%) were satisfied with the outcome after a median of 50 months. The median stool frequency increased from one to seven per week (<i>P</i><0.001). The number of patients with bloating, excessive straining and painful defecation decreased (<i>P</i><0.05). The laxative use decreased (<i>P</i><0.01) and faecal continence was unchanged. A blunted rectal sensation correlated to a poor outcome.</p><p>Fifty constipated patients with slow colonic transit and 28 controls were investigated with anorectal manovolumetry. Anal resting pressure was lower (<i>P</i><0.05), and squeeze pressure tended to be lower (<i>P</i>=0.09) in patients. Rectal sensation was not different between groups, although ten patients had a threshold for filling sensation above the 95^th percentile of controls. The rectal compliance was increased in patients (<i>P</i><0.05–0.01).</p><p>Total and segmental colonic transit was assessed with radio-opaque marker study and scintigraphy in 35 constipated patients, and related to normal values. Twenty-seven of 31 female patients had a prolonged total transit time on marker study, and 26 on scintigraphy. Of those 31 patients, 29 had prolonged segmental transit only in one or two segments on marker study. The two methods gave a similar result, except in the descending colon (<i>P</i><0.05). However, the results varied considerably for individual patients.</p><p>In conclusion, patients with STC often benefit from a segmental colonic resection, following assessment including scintigraphy. Anorectal physiology testing may predict surgical results.</p>

Oral 111-Indium-DTPA colonic scintigraphy was used to assess segmental transit in 23 patients with slow transit constipation (STC) and 13 controls. The transit time did not differ between patients and controls in the right colon, whereas the patients had a consistent delay from the transverse colon and distally (P&lt;0.05–0.001). Two individual patients had a delay in the right colon. Twenty-eight patients underwent a left- (n=26) or a right (n=2) hemicolectomy for STC, after evaluation including colonic scintigraphy. Twenty-three patients (80%) were satisfied with the outcome after a median of 50 months. The median stool frequency increased from one to seven per week (P&lt;0.001). The number of patients with bloating, excessive straining and painful defecation decreased (P&lt;0.05). The laxative use decreased (P&lt;0.01) and faecal continence was unchanged. A blunted rectal sensation correlated to a poor outcome. Fifty constipated patients with slow colonic transit and 28 controls were investigated with anorectal manovolumetry. Anal resting pressure was lower (P&lt;0.05), and squeeze pressure tended to be lower (P=0.09) in patients. Rectal sensation was not different between groups, although ten patients had a threshold for filling sensation above the 95th percentile of controls. The rectal compliance was increased in patients (P&lt;0.05–0.01). Total and segmental colonic transit was assessed with radio-opaque marker study and scintigraphy in 35 constipated patients, and related to normal values. Twenty-seven of 31 female patients had a prolonged total transit time on marker study, and 26 on scintigraphy. Of those 31 patients, 29 had prolonged segmental transit only in one or two segments on marker study. The two methods gave a similar result, except in the descending colon (P&lt;0.05). However, the results varied considerably for individual patients. In conclusion, patients with STC often benefit from a segmental colonic resection, following assessment including scintigraphy. Anorectal physiology testing may predict surgical results.