Introduction: Surgically Facilitated Orthodontic Therapy (SFOT) has been utilized for years to overcome the limitations encountered with traditional orthodontic treatment of dentoalveolar and alveoloskeletal malocclusions. The procedure, which consists of full flap corticotomies and bone grafting, has many proposed benefits including increased speed and range of tooth movement. The purpose of this study is to evaluate arch expansion in patients treated with SFOT and clear aligners. Materials and Methods: A retrospective cohort study design was used to evaluate 51 consecutive adult patients that were treatment planned for significant arch expansion with corticotomies, bone grafting, and clear aligners. 17 of the 51 patients refused the surgical procedure and served as controls. Eight transverse arch width measurements were obtained at three different time points (Initial, ClinCheck, Refinement). Five calculations were performed to determine the magnitude, predictability, and efficiency of arch expansion. Results: The difference in treatment time between the two groups was statistically significant at 5.2 months (P < .0001). On average, corticotomies reduced the length of treatment by 46% and increased the rate of expansion 2.4x. Patients that received SFOT achieved a greater magnitude (+28%) of expansion at a significantly higher rate (P< 0.002) than controls for all eight interarch measurements. The SFOT group displayed higher predictability (% goal achieved) and a smaller difference between predicted and achieved tooth movements for all measures obtained. The mean age for the entire sample was 42.81 (+12.51 years). Conclusion: Arch expansion with corticotomy-assisted clear aligner therapy is significantly more effective, efficient, and predictable than with clear aligners alone. The predictability of expansion with aligners appears to have a higher range than initially thought, even in patients that do not receive corticotomies.

No description available.

El río Colorado se ubica en la parte Norte de la Patagonia argentina y atraviesa con dirección Oestenoroeste - Sur-sureste un sector del país de condición árida y semiárida ubicado entre la Cordillera de los Andes y el océano Atlántico, con un recorrido cercano a los 1.000 km. Esta tesis doctoral aborda el estudio de las características hidrológicas y el estudio específico de las variaciones en el diseño de drenaje de un tramo testigo ubicado en un área predeterminada por su cartografía secuencial y fiable en relación con las posibles variaciones hidrogeomorfológicas. Dentro de la problemática general que presenta el río Colorado, se tuvo en cuenta la función del río Curacó, último tramo de la gran cuenca Desa-guadero Salado Chadileuvú, a la que le da carácter de exorreica. Las periódicas activaciones del Curacó crean serios problemas de salinidad en las cuencas media y baja del Colora-do, parcialmente mitigados en la actualidad por la represa Casa de Piedra. El levantamiento del dique Casa de Piedra, sobre la parte final del alto valle, alteró drásticamente el comportamiento del río en cuanto al arrastre de sólidos. Por acción de su gran embalse se produce la deposición del mate-rial trasportado en suspensión, dándole una nueva condición física -y en parte también química- a las aguas emergentes del dique, que han dejado en el lago las arcillas y el limo que trasportaban. Esos materiales, antes de existir el dique, se depositaban aguas abajo e impermeabilizaban naturalmente los canales en las áreas de regadío de los valles medio e infe-rior. El agua que vierte Casa de Piedra, casi carente de sedi-mento, tiene una capacidad erosiva mayor que la que fluye antes del embalse; esa condición permite reducir el tiempo de formación de meandros con respecto a sectores de aguas arriba de la presa. Esas condiciones han generado también el fenómeno conocido como aguas claras. El estudio ordena en el tiempo y el espacio las variaciones de curvas y meandros del tramo testigo, cuantificándolas. Aunque también se han visto alteradas las curvas de caudal y salinidad es en el gasto sólido donde el dique Casa de Piedra ha provocado los cambios más visibles y fundamentales en el ser y quehacer del río. La curva resultante de los nuevos valores refleja la situa-ción con respecto a la anterior y marca una fuerte disminu-ción en el acarreo. Esta tesis es además un aporte a poste-riores investigaciones interdisciplinarias, especialmente en el campo de la hidráulica y la geomorfología fluvial, dos disci-plinas bajo las cuales el río Colorado ofrece un amplio campo de estudios. El trabajo detecta, determina y cuantifica los cambios físicos y humanos generados por la presencia del dique, algunos ya evidentes y otros en trance de serlo. / The construction of Casa de Piedra dam, in the final stretch of Colorado river high valley, radically modified down waters the hydrologic river course, specially as regards sediment transport, the majority of which settles in the lake. Conse-quently, waters the dam distributes, contain a remarkable erosive capacity, and accelerate down waters hydrographic processes, increasing river meandering and bringing about what is known as the clear waters phenomenon causing adverse effects on watering zones. With the purpose of checking the fact in a quantitative way, cartographies from a certain stretch were taken, being this stretch considered a witness one in periods around 25 years, assessing meanders appearance and disappearance, and comparing these quantities with the variation -in the same sense-, that took place since Casa de Piedra start up. The quantities were sig-nificant considering the relatively short time gone by. The fact was checked in a new aero - photographic flight, according to which, in a shorter lapse, meanders number increased again in the witness stretch.

Yes / Purpose - Blur adaptation occurs when an observer is exposed to continuous defocus. However, it is unclear whether adaptation requires constant defocus, or whether the effect can still be achieved when the adaptation period is interrupted by short periods of clear vision. Methods - The study included 12 emmetropes and 12 myopes. All observers wore full refractive correction throughout the experiment. 1D and 3D of myopic defocus was introduced using spherical convex lenses. An automated system was used to place the blurring lens before the RE for varying periods of blurred and clear vision during adaptation. Participants watched a DVD at 3 m during each 15 min trial. Visual acuity was measured using Test Chart 2000 before and after adaptation. Results - Blur adaptation occurs to varying degrees depending on the periods of incremental blur exposure. Significant improvements in defocused visual acuity occur with continuous blur, equal blur and clear periods, as well as for longer blur periods. However, longer clear periods showed reduced adaptation and this trial is significantly different to the other three trials for both defocus levels (p < 0.001). No refractive group differences were observed for neither 1D nor 3D defocus (p = 0.58 and p = 0.19 respectively). Conclusions - Intervening periods of clear vision cause minimal disruption to improvements in defocused visual acuity after adaptation, indicating that blur adaptation is a robust phenomenon. However, when the exposure to clear vision exceeds the defocused periods, adaptation is inhibited. This gives insight into the effects of real-world tasks on adaptation to blur. / Ms Kiren A. Khan was supported by a School of Optometry and Vision Science PhD studentship.

Modifications to speech production made by adult talkers in response to instructions to speak clearly have been well documented in the literature. Targeting adult populations has been motivated by efforts to improve speech production for the benefit of the communication partners, however, many adults also have communication partners who are children. Surprisingly, there is limited literature on whether children can change their speech production when cued to speak clearly. Pettinato, Tuomainen, Granlund, and Hazan (2016) showed that by age 12, children exhibited enlarged vowel space areas and reduced articulation rate when prompted to speak clearly, but did not produce any other adult-like clear speech modifications in connected speech. Moreover, Syrett and Kawahara (2013) suggested that preschoolers produced longer and more intense vowels when prompted to speak clearly at the word level. These findings contrasted with adult talkers who show significant temporal and spectral differences between speech produced in control and clear speech conditions. Therefore, it was the purpose of this study to analyze changes in temporal and spectral characteristics of speech production that children aged 6-10 made in these experimental conditions. It is important to elucidate the clear speech profile of this population to better understand which adult-like clear speech modifications they make spontaneously and which modifications are still developing. Understanding these baselines will advance future studies that measure the impact of more explicit instructions and children's abilities to better accommodate their interlocutors, which is a critical component of children’s pragmatic and speech-motor development.

Deep gold mines use a vast amount of water for various purposes. After use, the water is pumped back to the surface. This process is energy intensive. The control is traditionally done with manual interventions. The purpose of this study is to investigate the effects of automated control on mine dewatering pumps. Automating mine dewatering pumps may hold a great number of benefits for the client. The benefits include electricity cost savings through load shifting, as well as preventative maintenance and pump protection procedures. By automating pumps, the client will benefit from operating more cost effectively and realising electricity cost savings. The equipment needed for pump automation and the procedures involved in the process are discussed as part of this study. A DSM project was implemented in the form of a pump automation project. All safety and quality procedures were followed and training was provided where needed to ensure that personnel understand their duties and responsibilities. This ensures the sustainability of the project after completion. The performance of the project was tested in manual mode, manual scheduled control, manual scheduled surface control and auto control. Manual intervention achieved the highest electricity cost saving of R8.25 million (11.4 MW load shift saving). To achieve this saving the system was exhausted to a point where columns and infrastructure started failing. Auto intervention achieved an electricity cost saving of R5.57 million (7.7 MW load shift savings). The auto intervention achieved a lower electricity cost savings compared to the manual intervention. However, taking all factors into account, such as the damage to infrastructure after a period of manual control, the auto intervention proved the best balance for controlling mine dewatering pumps to achieve savings on the cost of electricity and system sustainability for optimal control. Automated systems can avoid system overload and protect the infrastructure from exhaustion. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

Deep gold mines use a vast amount of water for various purposes. After use, the water is pumped back to the surface. This process is energy intensive. The control is traditionally done with manual interventions. The purpose of this study is to investigate the effects of automated control on mine dewatering pumps. Automating mine dewatering pumps may hold a great number of benefits for the client. The benefits include electricity cost savings through load shifting, as well as preventative maintenance and pump protection procedures. By automating pumps, the client will benefit from operating more cost effectively and realising electricity cost savings. The equipment needed for pump automation and the procedures involved in the process are discussed as part of this study. A DSM project was implemented in the form of a pump automation project. All safety and quality procedures were followed and training was provided where needed to ensure that personnel understand their duties and responsibilities. This ensures the sustainability of the project after completion. The performance of the project was tested in manual mode, manual scheduled control, manual scheduled surface control and auto control. Manual intervention achieved the highest electricity cost saving of R8.25 million (11.4 MW load shift saving). To achieve this saving the system was exhausted to a point where columns and infrastructure started failing. Auto intervention achieved an electricity cost saving of R5.57 million (7.7 MW load shift savings). The auto intervention achieved a lower electricity cost savings compared to the manual intervention. However, taking all factors into account, such as the damage to infrastructure after a period of manual control, the auto intervention proved the best balance for controlling mine dewatering pumps to achieve savings on the cost of electricity and system sustainability for optimal control. Automated systems can avoid system overload and protect the infrastructure from exhaustion. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015

<p>Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil. Nitrogen leaching increases after clear-cutting since the uptake by vegetation is greatly reduced.</p><p>In this study the soil chemistry of two clear-cut spruce stands in Halland, in southwest Sweden, has been analyzed. A previous study in these areas has indicated higher nitrate concentrations in the groundwater in one of the areas and thus a greater nitrogen leaching. Nitrogen deposition in the two areas is estimated to be the same and therefore the soil chemistry has been analyzed to evaluate if differences in the soil can have resulted in differences in the nitrate concentration in the groundwater. The hypothesis is that the area with higher nitrate concentrations in the groundwater has properties more favorable for nitrification, which would be especially apparent in a lower carbon to nitrogen ratio. The pH and storage of nitrate, ammonium, total carbon, total nitrogen and exchangeable cations was analyzed in soil samples from both areas. In addition, a study of stand properties and previous use of the areas was made.</p><p>The analyses performed in this study indicate that the soil properties could not explain the differences in nitrate concentration in the groundwater. The differences found between the areas were that the area with lower nitrate concentrations in the groundwater had higher nitrate and ammonium concentrations and higher pH in the soil. The reason for this might be that the soil in this area has larger capacity to bind elements. The fact that the soil samples were sampled during different seasons probably had a major effect on these results. The history and stand properties of the two areas were similar. According to site index one area was more fertile, which benefits nitrification. This fact was not confirmed by the analyses, but it probably caused the nitrification rate to be higher in this area.</p> / <p>Det stora nedfallet av föroreningar i form av kväve i framförallt sydvästra Sverige leder till försurning och övergödning av både skogsmarker och vattendrag. Kvävedepositionen i södra Sverige kan uppgå till 20 kg N/ha och år. Det kväve som inte tas upp av vegetationen ackumuleras i marken som efterhand riskerar att bli kvävemättad vilket ökar risken för kväveutlakning. Kväveutlakningen från svenska skogsmarker har visat sig kunna vara i samma storleksordning som från jordbruksmarker som anses vara en av de största orsakerna till ökande kvävehalter i sjöar och vattendrag. Kväveutlakningens storlek beror till stor del på hur stor del av markens kväveförråd som finns i den oorganiska formen nitrat eftersom den är en lättrörlig jon. Efter skogsavverkning ökar nitratutlakningen betydligt på grund av att det finns väldigt lite vegetation kvar som tar upp kväveföreningarna.</p><p>I den här studien har markkemin i två avverkade granskogsområden i Halland undersökts. Tidigare studier i dessa två områden har visat att halterna av nitrat var högre i grundvattnet i det ena området än i det andra, och således var även nitratutlakningen större i detta område. Eftersom kvävedepositionen anses vara densamma i de två områdena har markemin undersökts för att finna skillnader där som kan förklara de olika nitratnivåerna i grundvattnet. Hypotesen var att det ena området skulle ha mer gynnsamma förhållanden för nitrifikation, framförallt en lägre C/N-kvot. Markens förråd av nitrat- och ammoniumkväve, totalkol, totalkväve, utbytbara katjoner samt pH undersöktes i båda områdena. En studie av områdenas historia gjordes även för att kunna utesluta skillnader där som kunde ge upphov till skillnaden i nitrat i grundvattnet.</p><p>Slutsatsen som kan dras från studien är att de analyserade egenskaperna inte visade på mer gynnsamma förhållanden för nitrifikation i det ena området än i det andra. Ingen skillnad i C/N-kvot uppmättes. Skillnaderna som hittades var att området med lägst halter av nitrat i grundvattnet hade högst halter av oorganiskt kväve i marken och högre pH. Att nitrathalterna var högre i grundvattnet men inte i marken kan ha sin förklaring i att marken i det ena området har större förmåga att binda till sig kväve vilket gör att det inte lika lätt kommer ut i grundvattnet. Antagligen spelade det stor roll för dessa resultat att jordproven tagits vid olika årstider. Undersökningen av tidigare användningsområde i skogarna visade att de hade en tämligen liknade historia. Det ena området har enligt ståndortsindex högre bördighet vilket gynnar nitrifikation. Detta framgick dock inte av analyserna men är antagligen orsaken till de högre nitrathalterna i grundvattnet i detta område.</p>

The impacts of current forest management methods on surface water quality, especially in northern parts of Sweden, are largely unexplored. In this review reports linked to logging impacts on catchment biogeochemistry, (with special emphasis on boreal ecosystems) has been assessed. Logging disturbances in boreal forest catchments can change biogeochemical processes in soils by alter transpiration, soil conditions, temperature, soil microbial activities and water fluxes. Combined these changes can cause increased soil nutrient leaching to receiving waters. In the studies reviewed, dissolved organic carbon (DOC) concentrations and export generally increased after logging. Similar responses followed for phosphorous (P), but to a lesser extent for nitrogen (N). Streamflow and peakflow and the export of suspended matter (SM) can also be altered after logging. Removal of streamside vegetation may result in increased stream water temperatures and potentially affect lake water temperature, deepen the epilimnion and deplete oxygen (O2) concentrations. Increased wind exposure can resuspend sediments and potentially release bioavailable P. Affected lake water concentrations of N can be considered negligible after logging, whereas tot-P concentrations has shown to increase to an almost twofold level in some studies. The overall impact on the pelagic productivity are therefore most likely those connected to increased DOC and SM concentrations. The general impact on fish biomass can be considered insignificant. In conclusions, to improve future forest management and for further understanding concerning the biogeochemical environmental impacts that forestry might have on freshwaters, additional studies are still required.

In this study a new tool was developed that made new approaches possible for the successful implementation of Demand Side Management (DSM) projects. The new approaches are incorporated into a generic tool that makes it possible for Energy Services Companies (ESCos) to undertake DSM projects that were previously not possible with currently available technology. Through these new approaches, maximum results can be obtained on a sustainable basis on the clear water pumping systems of South African mines. The author was responsible and participated in four different investigations and implementations of DSM projects. These were grouped into three case studies. Each of these studies required different new innovations. The innovations described in this thesis include the adaptation of the Real-time Energy Management System (REMS) that was developed and marketed by HVAC International, to mines with intricate pumping systems, mines without any instrumentation and control infrastructure, as well as to mines that make use of a Three Pipe Water Pumping System. The tool developed and applied in these projects was part of Eskom's DSM programme. In this programme, large electricity clients who wish to shift electrical load out of peak periods, are assisted by having the total costs of such projects funded by Eskom. The fact that the clients will most likely enjoy substantial electricity cost savings, (by not having to pay the high peak prices), is a major attraction of this programme. Nevertheless, the programme is not moving as fast as it should. The National Energy Regulator (NER) has set an annual target of 153 MW load to be shifted since 2003. By the end of 2005, the accumulated target load to be shifted will be 459 MW. However, Eskom has indicated that an accumulated total of only 181 MW load will have been shifted by the end of 2005. This means that the Eskom DSM programme has actually only achieved 39% of its target. The innovations described in this thesis will help ESCos to address this shortfall more effectively / Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2006