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The purpose of this study was twofold: (a) Examine successful choral director beliefs about warm-ups and their successful practices in conducting warm-ups, and (b) examine the relationship of musical background, choral training and music teaching style of high school choral directors upon these beliefs and practices. Subjects were 365 high school choral directors from 28 states. Data were analyzed using descriptive analysis, correlation analysis, multivariate analysis of variance and multiple regression. Results indicated choral director's beliefs and practices differ as a function of musical back-ground, demographic characteristics, choral conducting training, and music teaching styles. Specifically, warm-up beliefs were predicted by knowledge of vocal health and variety of warm-ups. Conversely, those who relied on the warm-up time for discipline and focusing attention showed a significant negative relationship with their philosophy. From multiple regression analysis, doing choral warm-ups accounted for one-third of a director's overall success, predicted by 10 variables: (a) experience, (b) education, (c) teaching style teacher-directed performance, (d) teaching style deep-student learning, (e) warm-up literature and procedure, (f) planning warm-ups (g) warm-up content, (h) prior choral experience and piano background, (i) a foundation in music, and (j) a developed philosophy of choral warm-ups. However, having a philosophy about warm-ups did not predict successful teaching practices.

River-ice break-up in high-latitude regions, despite its brevity, is a fundamental process, representing the most dynamic and complex period of fluvial processes. Moreover, ice break-up has significant cascading ecological effects, with a different severity for mechanical vs. thermal break-up, and thus, motivates the importance of monitoring efforts. Classical research methods, such as fieldwork or analysis of photographs and aerial imagery, offer a general perspective on the timing of ice break-up but have safety and logistic issues caused by the dangers of unstable ice cover, the lag times between event occurrence and observation, and the frequent low visibilities. The emerging field of environmental seismology, which studies surface processes through seismic signals, provides an alternative solution to these shortcomings by continuously recording high temporal resolution data. Seismic sensing can potentially record any event within a set distance if the produced signal is powerful enough. Three geophones had monitored the subarctic Sävar River reach for 185 days to test the efficiency of seismic methods to capture ice-cracking events, and based on their characteristics, to identify thermal vs. mechanical ice break-up. With visual and multivariate analysis, seismic methods provided a conservative set of 2 228 events, detected at milliseconds precision, described, and located. Besides, both trigger lag times and principal component analysis depicted correlations between environmental drivers and ice-cracking events. The automatic picker based on duration and trigger thresholds required manual supervision because of the initial numerous false signals that accounted for 96% of total initial events. Ice-cracking signals as short as 0.2s and frequencies of 8-40 Hz with an average power of -117 dB were statistically defined, classified, and described by case events as two types, associated, based on their spectral and temporal patterns, with the two ice break-up modes. With an estimated Rayleigh wave velocity of 680 m/s, all ice-cracking signals' locations were within the instrumented area. Trigger lag times analysis improved detection and showed a strong link between ice-cracking events and drivers of lag times less than three hours, including near-immediate responses (< 2s). With multivariate analysis, the lag times showed a mainly climatic control for thermal melting and a primarily fluvial control in mechanical ice break-up. The combination of statistical and seismic analysis provides, despite the considerable manual screening, a valid and potentially site-transferable method to extract and describe ice-cracking signals and thus identify ice break-up modes in northern rivers.

Der zunehmende Bedarf nach digitalen Speichermedien macht die Erforschung von neuen Materialien für zukünftige Technologien von nichtflüchtigen Speichern nötig. Hierfür eignen sich zum Beispiel Metall-Nanopartikel, die in organischen Halbleiterschichten eingebettet sind. Aufgrund der bistabilen Schaltbarkeit der Leitfähigkeit von Metall-Nanopartikeln lassen sie sich in Abhängigkeit der elektrischen Umgebungsbedingungen entweder in einen niedrig- oder einen hochleitenden Zustand schalten. Bisher wurden verschiedene Modelle entwickelt, um den Schaltmechanismus von Speichern mit einem organischen Matrixmaterial zu erklären, jedoch fehlt bislang ein konsistentes Bild zum Verständnis des Schaltvorgangs. Die vorliegende Arbeit  untersucht die Rolle des Raumladungsfeldes ausgehend von Metall-Nanopartikeln in Bauelementen. Dazu wurde eine Reihe von Experimenten zur Bestimmung der elektronischen und elektrischen Eigenschaften durchgeführt, um die tatsächliche Rolle des Raumladungsfeldes aufzuklären. Mit Hilfe von Röntgen- und UV-Photoelektronenspektroskopie wurde die Wechselwirkung zwischen den Metall-Nanopartikeln und den prototypischen organischen Halbleiterschichten detailliert untersucht. Unter Verwendung der bereits untersuchten Materialien wurden Bauelemente hergestellt und charakterisiert. Die Ergebnisse zeigen, dass der allgemein vorgeschlagene Mechanismus bezüglich der Aufladung/Entladung von Metall-Nanopartikeln als Ursache für die elektrische Bistabiliät in einem zweipoligen Bauteil ausgeschlossen werden kann. Stattdessen stützt dieses Ergebnis den alternativen Mechanismus der Filamentbildung. Zur Untersuchung der Skalierbarkeit der Speicher im Nanometerbereich wurden die Strukturen durch das Abscheiden der Materialien bei streifendem Einfall präpariert. Die entsprechenden Nanospeicher wurden elektrisch charakterisiert und zeigten Bistabilität. Folglich sind diese Nanspeicher besonders attraktiv für zukünftige Technologien in Hinblick auf hohe Speicherdichten. / The increasing need to store digital information has triggered research into the exploration of new materials for future non-volatile memory (NVM) technologies. For instance, metal nanoparticles (MNPs) embedded into organic semiconductors are suitable for novel memory applications because they were found to display bistable resistive switching. Different switching models were hitherto developed to explain the fundamental mechanisms at work in resistive NVMs. This thesis explores specifically the role of space-charge field due to the charging of MNPs as rationale for resistive switching in two-terminal devices. A series of experiments on the electronic and electrical properties of devices were conducted in order to reveal whether this mechanism is, indeed, at play in resistance switching. Photoelectron spectroscopy provided detailed information about the interaction between gold nanoparticles (AuNPs) with prototypical organic semiconductors used in optoelectronics. The study of the electronic valence structures provided evidence of a space-charge due to the charging of AuNPs. Furthermore, it is found that charge-neutrality of AuNPs can be dynamically re-established upon illumination, through electron transfer from excitons. Devices were built with the same materials investigated by photoemission spectroscopy and electrical characterization was conducted. Despite the previously demonstrated ability to optically change the charging state of the AuNPs, the devices do not display any bistability. This finding provides evidence that the commonly proposed charging/decharging mechanism of MNPs can be excluded as cause for electrical bistability in NVM devices. In order to explore the scaling of resistive NVMs into the nanometric range, glancing angle deposition technique was employed. The nano-NVMs were electrically characterized and it is proved to manifest resistive bistability. These finding make nano-NVMs highly appealing for future high-density memory technology.

It is well known that a parental break-up in childhood has a negative influence on the intergenerational contact in adulthood. The intergenerational contact within dissolved families is less frequent than in intact families. Nonetheless, even among families that experienced a break-up in childhood, differences in contact frequency are observable. How come those individuals seem to be affected in different ways by a parental break-up? Previous research is lacking the answer to this question. Thus, the aim of this thesis is to contribute to research on dissolved families by exploring which conditions influence intergenerational contact among adult children and their divorced/separated parents. The data used in this thesis come from the Swedish Level of Living Survey and the analyses are conducted using OLS-regressions. First, it was verified that dissolved families have a less frequent intergenerational contact than intact families in contemporary Sweden, however, with the exception of the contact between divorced/separated mothers and their daughters. Second, the variation in contact among dissolved families is, to a large part, explained by differences in living distance between the adult child and the parent. Furthermore, it was found that conflict between the respondent and the parent in childhood has a significant influence on intergenerational contact in adulthood. The results thus highlight the importance of including childhood events other than the divorce/separation when investigating intergenerational contact.

In order to enhance the inherent potential of cooperatives to support society’s move towards global socio-ecological sustainability, they need to plan strategically. Strategic planning with this goal in mind requires organisations to describe and identify steps towards a desired future. The research team set out to provide practical and context-appropriate guidance to cooperatives, describing opportunities to use strategic planning in the starting-up phase in support of their long-term success. The team deployed a qualitative and iterative approach based on grounded theory and conducted a total of twenty-four interviews with cooperative practitioners and experts as well as strategic planning experts.  The outcome of the interviews are thematic areas recommended to cover in the starting-up phase of a cooperative. The thematic areas are presented in an ABCD Strategic Planning process which aims to build a shared mental model among all stakeholders, using a participatory approach. The process may be useful for newcomers to the cooperative world; future research in support of cooperatives may want to implement the above mentioned strategic planning process while capturing lessons for its improvement.

It is well established that atherosclerosis, an inflammatory response to chronic injury in the blood vessel wall, plays a leading role in the development and progression of cardiovascular disease. Mineralocorticoid receptor (MR) over-activation has been implicated in atherosclerosis. In mineralocorticoid-target tissues, 11β- Hydroxysteroid dehydrogenase type 2 (11β-HSD2) inactivates glucocorticoids, conferring aldosterone specificity upon the normally unselective MR. Recent evidence suggests that 11β-HSD2 may also afford protection of MR in the cells of the vasculature, providing possible mechanisms by which MR activation may directly promote atherosclerosis. Consistent with this, Apoe-/-/11β-HSD2-/- double knockout (DKO) mice show accelerated atheroma development. The present thesis tested the hypothesis that inactivation of 11β-HSD2, allowing inappropriate activation of MR in cells of the vasculature, accelerates atherogenesis through promotion of a pro-inflammatory environment with increased endothelial cell expression of adhesion molecules and subsequent macrophage infiltration into plaques. DKO mice received either the MR antagonist eplerenone (200mg/kg/day) or vehicle in normal chow diet from 2 months of age for 12 weeks. Eplerenone significantly decreased atherosclerotic burden in brachiocephalic arteries of DKO mice, an effect that was accompanied by alterations in the cellular composition of plaques such that a more stable collagen- and smooth muscle cell- rich plaque was formed. Eplerenone treatment was also associated with a reduction in vascular inflammation as demonstrated by a significant reduction in macrophage infiltration into DKO plaques. The accelerated atherogenesis in DKO mice was clearly evident by 3 months of age, a time point at which Apoe-/- mice were completely lesion free. By 6 months, some Apoe-/- mice had developed lesions whilst all DKO mice at this age showed much larger plaques. Compared to Apoe-/- mice, the cellular composition of DKO plaques was altered favouring vulnerability and inflammation, with increased macrophage and lipid content and decreased collagen content. To investigate the possible underlying mechanisms responsible for increased inflammatory cell content, the expression of vascular cell adhesion molecule 1 (VCAM-1) was compared in DKO and Apoe-/- brachiocephalic arteries. VCAM-1 immunostaining was significantly greater on the endothelial cells of DKO arteries at 3 months compared to age-matched Apoe-/- mice. At 6 months, DKO and Apoe-/- mice had similar expression of VCAM-1. Finally, mouse aortic endothelial cells (MAECs) were used to investigate the mechanism of adhesion molecule up-regulation in the absence of 11β-HSD2. Both aldosterone and TNF-α, included as a positive control, dramatically increased VCAM-1 expression in MAECs. Spironolactone pre-treatment blocked the effect of aldosterone, suggesting an MR-mediated mechanism. Corticosterone alone had no effect on VCAM-1 expression. However, inhibition of 11β-HSD2 by pre-treatment with glycyrrhetinic acid allowed corticosterone to induce a significant increase in the number of VCAM-1-stained MAECs, demonstrating functional expression of 11β- HSD2 in MAECs. Consistent with 11β-HSD2 involvement, VCAM-1 up-regulation by corticosterone in the presence of glycyrrhetinic acid was reversed by blockade of MR with spironolactone. In conclusion, loss of 11β-HSD2 activity leading to inappropriate activation of MR in atherosclerotic mice promotes plaque vulnerability and increases vascular infiltration of macrophages which accelerates plaque growth, possibly through enhanced MR- mediated endothelial cell expression of VCAM-1.

Studien syftar till att analysera processer och relationer i den nätverksstruktur som innefattar både lokala, regionala och statliga aktörer i megaprojektet Ostlänken, med tonvikt på de små kommunerna Nyköping och Trosa. Uppsatsens teoretiska förhållningssätt härrör från forskning inom nätverksstyrning (governance) och megaprojekt. Dessa forskningsteman används i den valda metodansatsen för att vidare kunna beskriva och tolka nätverksstyrning för ett megaprojekt i den lilla kontexten. Forskningsstudien utgör således en kvalitativ sådan, där insamling av primärbaserad data sker genom intervjuer med olika beslutsfattare på nationell, regional och lokal styrningsnivå. Studiens resultat visar hur de mindre kommunerna kompenserar för ett maktunderskott genom att dels tillsammans med andra lokala och regionala aktörer samverka i nätverk, dels genom att komma med ett väl genomarbetat underlag för planering av Ostlänken till staten. Relationerna inom Ostlänkens nätverksstruktur påvisar att det råder en storstadsnorm på statlig nivå. Denna norm återges av att staten låter sig uppföra krav på bland annat befolkningsmängd, för de kommuner som eftersträvar en stationslokalisering, samt att en uttalad ändpunktstrafik bör råda mellan de tre storstadsregionerna Stockholm-Göteborg-Malmö. En ytterligare konklusion är hur det anses behöva lokala och regionala påverkansnätverk för att ett projekt av en sådan dignitet ska kunna förverkligas, vilket belyser statens tillbakadragna roll och en planeringsprocess karaktäriserad av bottom-up.

Thesis ((MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: When constructing a submarine pipeline, construction teams must work in the hostile environment in the ocean known as the surf zone. The surf zone is the area along a shoreline stretching between the first evident point of wave breaking and the beach line. In order to ensure that the pipeline is shielded from the imposing forces within the surf zone, engineers use a burial technique which leaves the pipeline length in the surf zone buried underneath the active seabed once construction is finished. Thus a temporary surf zone trench is dredged and protected by an open-ended cofferdam built using iron sheet piles. As a result of the incoming wave climate and the surf zone currents created by this wave climate, sedimentation in and around the trench becomes problematic. In this study alternative geometric layouts for the open-ended cofferdam protecting the surf zone trench are investigated, attempting to minimize the sediment build-up in and around the trench. This was done by using both a 3D qualitative physical model conducted at the CSIR in Stellenbosch, and numerical model using MIKE developed by DHI. However, this study only considers sediment build-up and not structural integrity and constructability of the cofferdam designs. Combining the observations of both the physical- and numerical models, a conclusion was drawn that a structure built perpendicular to the shoreline with a 45oextended arm built from the upstream edge of the cofferdam wall, is the most effective. No dimensions are given as the cofferdam design will change depending on the site specific characteristics. Also an increase in structure length will result in the mouth of the structure being located outside the active sediment zone, which leads to a longer period of time before the pipeline pathway is compromised by sediment. / AFRIKAANSE OPSOMMING: Tydens die konstruksie van 'n onderwaterse pyplyn, moet konstruksie spanne in 'n gevaarlike gedeelte van die see werk naamlik die brandersone. Die brandersone kan gedefinieer word as die area tussen die eerste punt waar branders breek en die strandlyn. Om die pyplyn te beskerm teen die kragte wat branders op dit uitoefen, gebruik ingenieurs 'n installasietegniek waar hul die brandersone seksie van die pyplyn onder die aktiewe seebodem begrawe. Om die tegniek te bewerkstellig, grawe kontrakteurs 'n sloot deur die brandersone en beskerm dit met 'n tydelike struktuur bekend as 'n kofferdam. As gevolg van die inkomende branders en die strome wat deur die branders aangedryf word, kan die opbou van sediment in, en rondom die sloot in die brandersone problematies word. Hierdie studie ondersoek alternatiewe uitlegte vir die tydelike kofferdam struktuur met die oog daarop om die opbou van sediment in, en rondom die struktuur te verminder. Die doel was nagestreef deur gebruik te maak van beide 'n 3-dimensionele fisiese model, gebou en gebruik by die WNNR in Stellenbosch, en 'n numeriese model wat op MIKE, ontwikkel deur DHI gedoen was. Let wel die studie het slegs die sediment beweging in die nabye area van die tydelike kofferdam struktuur in ag geneem en nie die praktiese implimentering en strukturele integriteit van die struktuur nie. Deur die observasies van beide die fisiese- en numeriese modelering in ag te neem, is die volgende gevolgtrekkings gemaak. 'n Struktuur wat loodreg met die strandlyn gebou is en met 'n 45o arm wat na die stroom-op kant toe uitstrek, was die mees effektiewe een. Geen dimensies is deurgegee nie aangesien die ontwerp sal verskil afhangende van die spesifieke area waar die projek aangepak word. Daar is ook gesien dat indien die struktuur langer gemaak word, sal die kontrakteur langer tyd h^e voordat daar sediment probleme in die brander sone sloot ondervind sal word.

Female stand-up comics occupy a permanently liminal space which can be broken down into three small areas, characterized thusly: the interpersonal, the sexual and the professional spheres. Issues of power, footing and the carnivalesque are threaded throughout these three spaces, and I use the work of Michel Foucault, Mikhail Bakhtin and Erving Goffman to examine the ways in which the female comics I talked, lived and performed with over a two-year period negotiate this permanent liminality to both their advantage and their detriment. The three liminal spaces overlap and intersect, with female comics occupying at times two, and sometimes all three, at any given moment, in a constantly forming and re-forming state of “otherness” that separates them from the default male comic body. In locating female comedians in a permanent liminality, I illustrate the structures at play that are demonstrative not only of the comic experience, but of larger issues surrounding gender in contemporary society. / text