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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.
151

Evolução da capacidade de regularização do sistema hidrelétrico brasileiro. / Evolution of storage capacity in the brazilian hydropower system.

Falcetta, Filipe Antonio Marques 20 August 2015 (has links)
No Brasil, cerca de dois terços da capacidade total instalada de geração de energia elétrica e, em média nos últimos quinze anos, aproximadamente 90% da geração efetiva provêm das hidrelétricas. Este sistema inclui 170 usinas hidrelétricas de médio e grande porte existentes ou previstas até 2023, aproximadamente dois terços delas com capacidade de regularizar vazões e todas operando de maneira interligada. Restrições ambientais, técnicas, sociais e econômicas tem dificultado cada vez mais a implantação de empreendimentos hidráulicos contendo reservatórios de grande porte, tornando a maioria dos novos empreendimentos a fio d´água. Para compreender melhor o processo, este trabalho apresenta um levantamento da evolução anual da capacidade instalada e de armazenamento do sistema desde 1950 até a expansão prevista nos próximos 8 anos, em 2023. Os dados da década de 2000 e a previsão até 2023 de forma ainda mais acentuada indicam uma redução continua e significativa da capacidade relativa de regularização, com impacto direto nas decisões de operação e de expansão do sistema térmico complementar. A fim de avaliar as possíveis consequências da redução da capacidade de regularização, simulações foram realizadas no modelo HIDROTERM (ZAMBON et al. 2012); os resultados apontam para uma necessidade de ser complementar continuamente a energia hídrica, não só em períodos hidrologicamente desfavoráveis. / In Brazil, about two-thirds of electricity installed capacity and over the last fifteen years, on average 90% of energy consumed has come from hydropower generation. The hydro system includes 170 medium and large hydropower plants in integrated operation today or planned to be operational by the end of 2023, about two-thirds of them have large storage capacities to regulate flows. Environmental, technical, social and economic constraints have made it increasingly difficult to project and build new reservoirs with large storage capacities. As a result, newly built hydropower plants are mostly the run-of-river type. To better understand the process, this paper presents a historical survey of the installed capacity of hydropower and storage capacity of the system since 1950 and extends to the planned expansion over the next eight years, through 2023. Data from 2000 and projections through 2023 indicate a significant reduction of relative regulating capacity, which has a direct impact on decisions regarding operation and expansion of the complementary thermal system. In order to assess the possible consequences of the reduction in regulating capacity, simulations were performed on HIDROTERM model (ZAMBON et al. 2012); the simulation results point to a continuous need for complementing the hydropower generation, not only on hydrologically unfavorable years.
152

Design Evaluation of a Duplex Circular Wet Well Pumping Station Under Steady State and Dynamic Operating Conditions

Mailloux, James Thomas 29 April 2010 (has links)
Duplex Circular Wet Well (DCWW) lifting pump stations are utilized for pumping clear and solid-bearing liquid. Understanding the effect of design criteria on pump performance is important to minimize maintenance costs and maximize efficiency. There are currently no known full-scale laboratory studies that have been performed to investigate the overall design of DCWWs. The objective of the research was to evaluate the impact of various design criteria, such as internal geometry and operating conditions on the performance of DCWW pump stations and provide documentation and recommendations which will be used to augment the current Hydraulic Institute/American National Standard for Pump Intake Design (ANSI/HI 9.8-1998), (HI) guidelines. The research was conducted in two phases; Phase 1 consisted of performing a comparative analysis of the basic flow patterns within the wet well by means of Computational Fluid Dynamics (CFD), Phase 2 consisted of performing detailed evaluations of various design aspects on pump performance using a full-scale Physical Model constructed for the research. The CFD research provided indications regarding potential performance problems that may occur due to poor flow patterns and potential pump suction swirl, while the physical research provided a basis for determining the relative advantages of different designs. The physical research included the evaluation of general flow patterns, free-surface and subsurface vortices, air entrainment and pump suction swirl. Measurement of the steady state swirl within the pump showed unacceptable performance in accordance with the HI acceptance criteria. Swirl data collected under real-world dynamic operating conditions showed that the pump typically did not experience the adverse conditions indicated at steady state. Normal (symmetrical) pump orientation resulted in more favorable operation in terms of pump swirl and ingestion of entrained air than a coplanar (inline) condition. A minimum water elevation was established to minimize air-entrainment and swirl entering the pumps, reducing possible effects such as cavitation and vibration of the pump impeller. Air-core subsurface vortices were present under the pumps, requiring pump-cones to be installed. The collection of real-time dynamic data will allow design engineers to better understand actual pump performance under normal cycling and clean-out modes, reducing the operating time under unfavorable conditions and overall maintenance requirements.
153

Experimental fabrication and characterisation of textile metamaterial structures for microwave applications

Greinke, Berit January 2017 (has links)
This thesis presents an investigation of fabrication technologies and electromagnetic characterisation of textile metamaterials in the microwave frequency range. Interdisciplinary in nature, the work bridges textile design practice and electromagnetic engineering. The particular ambition was to explore a number of surface techniques prevalent in the textile design field, and map their suitability for the construction of metatextiles for microwave operation. Two different classes of metatextiles, all-dielectric and dielectric with electrically conductive patterns, were examined. First, five structures of all-dielectric textiles and papers are reported; three textiles with graded embroidered and screen printed patterns, and two papers embellished with regular and irregular laser cut patterns. Permittivities for these materials were measured in a purpose-built test chamber and shown to be similar to permittivity ranges exhibited by solid discrete metamaterial cells previously reported in the scientific literature. Importantly these metatextiles were realised within one textile surface and one fabrication process, bypassing the need to assemble large numbers of isotropic material cells. This reveals the potential for rapid and low-cost manufacture of graded textile materials to produce anisotropic ground plane cloaks. Secondly, three studies are presented that examine the use of electrically conductive patterned textile materials in the design of metatextiles which exhibit negative refractive index over a narrow frequency band. A range of e-textile (electronic textile) fabrication technologies were explored to assess their suitability for prototyping splitring and wire arrays, resonating in a narrow region between 3 - 10 GHz. Designs utilised a repeated unit cell pattern on a two-dimensional textile surface and were subsequently pleated into the required three-dimensional structure. A small negative refractive index was achieved for an embroidered prototype at 4.9 GHz, and two 'printed and plated' prototypes at, 7.5 GHz and 9.5 GHz respectively. In summary the thesis demonstrates a set of guidelines for the fabrication of textile metamaterials for microwave frequencies, derived through a practice-led and interdisciplinary method based on material experimentation.
154

Hospital cost inflation : economic approaches for policy analysis.

Kazdin, Robert Alan January 1979 (has links)
Thesis. 1979. M.S.--Massachusetts Institute of Technology. Alfred P. Sloan School of Management. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND DEWEY. / Includes bibliographical references. / M.S.
155

Contribuição para o estudo das distâncias de visibilidade de ultrapassagem para rodovias bidirecionais com duas faixas de tráfego. / Study of passing sight distance on two lane highways.

Pellegrini, Paulo Tomaz 29 May 2006 (has links)
Parcela expressiva do transporte de cargas e de passageiros é realizada atualmente no Brasil pelo modo rodoviário, sendo que mais de 90% da malha viária federal é composta por rodovias bidirecionais com duas faixas de tráfego. A necessidade de manobras de ultrapassagem neste tipo de rodovia é bastante comum e a falta de oportunidades para que elas se realizem pode comprometer a eficiência operacional e condições gerais e específicas de segurança ao longo da via. O principal parâmetro de projeto relacionado às manobras de ultrapassagem é a Distância de Visibilidade de Ultrapassagem (DVU). Hoje há critérios distintos para a fixação dos valores mínimos de projeto para este parâmetro: a DVU dimensionada pelo critério geométrico é aplicada no desenvolvimento do projeto de geometria da rodovia e a DVU dimensionada pelo critério de sinalização é utilizada no projeto de sinalização da via. Os valores mínimos de DVU recomendados diferem bastante de um critério para outro, assim como as considerações pertinentes ao dimensionamento dos mesmos. No Brasil as referências para os valores estabelecidos são o Manual de Projeto Geométrico de Rodovias Rurais e o Manual de Sinalização Rodoviária, ambos publicados em 1999 pelo extinto DNER (atual DNIT). Quando se considera, por um lado, que as metodologias para estabelecimento dos mencionados valores mínimos são fundamentadas em estudos e pesquisas de campo realizados nos Estados Unidos na primeira metade do século passado e, por outro lado, o avanço das características técnicas das rodovias e dos veículos em circulação bem como as alterações ocorridas no comportamento dos motoristas ao longo das últimas décadas, torna-se evidente a necessidade de revisão de tais metodologias. Considerando sua aplicação às rodovias brasileiras, julga-se conveniente o desenvolvimento de pesquisas sobre a realização de manobras de ultrapassagens na malha viária nacional, com o objetivo de verificar se os valores da DVU atualmente em uso são adequados. Neste sentido, este trabalho apresenta uma análise crítica dos principais modelos e critérios hoje adotados no país e no Exterior, com base em ampla pesquisa bibliográfica e no levantamento de dados relacionados a manobras de ultrapassagem observadas em três rodovias do Estado de São Paulo, assim como a proposição de modelos alternativos para a definição de valores mínimos para a DVU segundo o critério geométrico e o critério de sinalização. / Today, most of the transportation in Brazil – of both people and goods - uses the country’s highway system. Two-lane highways represent over 90% of the federal highway network. Passing maneuvers are often required on such highways and the lack of opportunities may compromise operational efficiency and safety conditions. Passing Sight Distance (PSD) is the key project parameter related to passing maneuvers. Today, there are two different methods to establish minimum PSD design values: the geometric criteria, which are used highway on geometric design, and the signaling criteria, used to mark pavement surface. Minimum PSD values recommended by geometric criteria and signaling criteria are often very different, as well as the assumptions on which these models are based. In Brazil the references adopted are the Highway Design Manual for Rural Highways (Manual de Projeto Geométrico de Rodovias Rurais) and the Highway Signaling Manual (Manual de Sinalização Rodoviária), both published in 1999 by DNER (today called DNIT). Considering that the recommended values are based on field studies carried out in the United States in the first half of the 20th century, it is clear that these criteria must be reviewed, specially taking into account the technical advances of highways and vehicles, as well as the changes occurred in driving behavior over the last decades. Considering the application to Brazilian highways, it is important to research passing maneuvers through national roads in order to verify the adequacy of PSD values adopted. Therefore, this work presents a critical analysis of major models used today in Brazil and abroad, based on extensive bibliographical research and on field studies related to passing maneuvers in three highways in São Paulo State. New models to determine minimum PSD values are also proposed for both geometric and signaling criteria.
156

Evolução da capacidade de regularização do sistema hidrelétrico brasileiro. / Evolution of storage capacity in the brazilian hydropower system.

Filipe Antonio Marques Falcetta 20 August 2015 (has links)
No Brasil, cerca de dois terços da capacidade total instalada de geração de energia elétrica e, em média nos últimos quinze anos, aproximadamente 90% da geração efetiva provêm das hidrelétricas. Este sistema inclui 170 usinas hidrelétricas de médio e grande porte existentes ou previstas até 2023, aproximadamente dois terços delas com capacidade de regularizar vazões e todas operando de maneira interligada. Restrições ambientais, técnicas, sociais e econômicas tem dificultado cada vez mais a implantação de empreendimentos hidráulicos contendo reservatórios de grande porte, tornando a maioria dos novos empreendimentos a fio d´água. Para compreender melhor o processo, este trabalho apresenta um levantamento da evolução anual da capacidade instalada e de armazenamento do sistema desde 1950 até a expansão prevista nos próximos 8 anos, em 2023. Os dados da década de 2000 e a previsão até 2023 de forma ainda mais acentuada indicam uma redução continua e significativa da capacidade relativa de regularização, com impacto direto nas decisões de operação e de expansão do sistema térmico complementar. A fim de avaliar as possíveis consequências da redução da capacidade de regularização, simulações foram realizadas no modelo HIDROTERM (ZAMBON et al. 2012); os resultados apontam para uma necessidade de ser complementar continuamente a energia hídrica, não só em períodos hidrologicamente desfavoráveis. / In Brazil, about two-thirds of electricity installed capacity and over the last fifteen years, on average 90% of energy consumed has come from hydropower generation. The hydro system includes 170 medium and large hydropower plants in integrated operation today or planned to be operational by the end of 2023, about two-thirds of them have large storage capacities to regulate flows. Environmental, technical, social and economic constraints have made it increasingly difficult to project and build new reservoirs with large storage capacities. As a result, newly built hydropower plants are mostly the run-of-river type. To better understand the process, this paper presents a historical survey of the installed capacity of hydropower and storage capacity of the system since 1950 and extends to the planned expansion over the next eight years, through 2023. Data from 2000 and projections through 2023 indicate a significant reduction of relative regulating capacity, which has a direct impact on decisions regarding operation and expansion of the complementary thermal system. In order to assess the possible consequences of the reduction in regulating capacity, simulations were performed on HIDROTERM model (ZAMBON et al. 2012); the simulation results point to a continuous need for complementing the hydropower generation, not only on hydrologically unfavorable years.
157

Inzidenz und Verlauf der Antimetaboliten-induzierten kornealen Epitheliopathie nach intra- und postoperativer 5-Fluorouracil-Applikation / Incidence and progress of antimetabolite-induced corneal epitheliopathy after intra-and postoperative 5-fluorouracil application

Wimmer, Svea January 2013 (has links) (PDF)
Einleitung Die zytotoxische Wirkung von 5-Fluorouracil auf Bindehaut-Fibroblasten wird gezielt eingesetzt, um die Vernarbung des Sickerkissens zu reduzieren. Zu den dabei auftretenden Nebenwirkungen zählen Epitheliopathien der Hornhaut. Deren Inzidenz und Verlauf sind Gegenstand dieser Arbeit, ebenso wie der Einfluss von 5-FU auf OP-Erfolg und damit vergesellschaftet die Drucksenkung, den Visus, die Sickerkissenentwicklung und die notwendige Medikation. Methoden 103 nicht voroperierte Augen mit präoperativ gesunder Hornhaut wurden eingeschlossen. Alle Augen erhielten während der Trabekulektomie 5mg 5-FU und wurden anhand ihrer postoperativen Behandlung ohne oder mit 5-FU einer unbehandelten Kontrollgruppe, einer Niedrigdosisgruppe (bis max. 35mg) oder einer Hochdosisgruppe (über 35mg) zugeteilt. Dokumentiert wurden Auftreten, Ausdehnung und Dauer von postoperativen Erosionen und das Auftreten und Ausmass von Stippungen während der 5-FU-Serien. Sickerkissenbefund, Visus, IOD und Medikation wurden präoperativ, drei und zwölf Monate postoperativ ausgewertet, ebenso der Hornhautbefund nach drei und zwölf Monaten. Ergebnisse Die Erosioinzidenz war in der Hochdosisgruppe mit 81% signifikant höher als in der Niedrigdosis- (63%) und in der Kontrollgruppe (10%; p=0,046 bzw. p=0,002). Die Erosiones traten durchschnittlich am 21. postoperativen Tag auf, waren durchschnittlich bei 44% der Patienten kleiner als die halbe Hornhaut und nach durchschnittlich zehn Tagen ausgeheilt. Es zeigte sich, dass die Erosionsdauer moderat positiv mit der bis zum Auftritt injizierten 5-FU-Dosis korrelierte (p=0,009). Hornhautstippungen traten bei 90% der Patienten mit postoperativer 5-FU-Gabe während der Injektionsserien auf. Drei Monate postoperativ hatte die Hochdosisgruppe signifikant mehr Hornhaut-Epitheliopathien (59%, davon 9% Erosiones) als die Niedrigdosis- (29%) und die Kontrollgruppe (10%; p=0,001) zu verzeichnen. Ein Jahr nach Trabekulektomie wies nur noch die Hochdosisgruppe noch einen Trend zu Epitheliopathien in Form von Stippungen auf (21%; p=0,09). Der Sickerkissenbefund war in der Niedrigdosisgruppe nach drei und nach zwölf Monaten am Besten (p=0,023 bzw. p=0,042). Der Visus unterschied sich an den Untersuchungszeitpunkten zwischen den Gruppen nicht, er wurde in allen drei Gruppen insgesamt postoperativ schlechter, zeigte jedoch nach einem Jahr eine Besserungstendenz zum Drei-Monatswert, in der Hochdosisgruppe in signifikantem Ausmass (p=0,012). Der Augeninnendruck wurde von präoperativ zu drei Monate postoperativ durchschnittlich um 43% und von präoperativ zu zwölf Monate postoperativ durchschnittlich um 35% gesenkt, letzteres in der Niedrigdosisgruppe (um 45,4%) signifikant stärker als in der Hochdosisgruppe (um 27,9%; p=0,031). Gute und sehr gute OP-Erfolge wurden nach drei Monaten bei durchschnittlich 76% (70%, 80% und 78% in Kontroll-, Niedrig- und Hochdosisgruppe) beobachtet und nach zwölf Monaten bei durchschnittlich 66% der Patienten (60%, 87% und 50% in Kontroll-, Niedrig- und Hochdosisgruppe). Die topische Gesamtmedikation, d.h. Glaukommedikation zuzüglich Oberflächenpflege, war nach drei Monaten in der Hochdosisgruppe signifikant höher als in der Niedrigdosis- und Kontrollgruppe (p=0,003 bzw. p=0,04). Dies galt insbesondere für die Oberflächenpflege (p=0,01 bzw. p=0,041). Eine systemische medikamentöse Drucksenkung war nach drei Monaten nur noch in der Hochdosisgruppe erforderlich (3,45%) und ein Jahr postoperativ war allein die Niedrigdosisgruppe frei von antiglaukomatösen Tropfen. Schlussfolgerung Unerwünschte Komplikationen durch 5-FU-Anwendung treten mit zunehmender Dosierung häufiger auf. Höhere 5-FU-Dosen sind jedoch in Abhängigkeit von der Sickerkissenentwicklung teilweise erforderlich. Bei Hochdosis-Therapie mit 5-FU kann bei erhöhter Nebenwirkungsrate dennoch bei bis zu 50% der Patienten (nach einem Jahr) ein OP-Erfolg gesichert werden. Eine Langzeitschädigung des Epithels durch 5-FU konnte, unabhängig von der Dosis, nicht nachgewiesen werden. Damit ist der postoperative Einsatz von 5-FU nach individueller Abwägung des Risiko-Nutzen-Faktors gerechtfertigt. / Introduction The cytotoxic effect of 5-fluorouracil on conjunctival fibroblasts is specifically used to reduce the scarring of the filtering bleb. The occurring side effects include epitheliopathy of the cornea. Their incidence and progression are the subject of this work, as well as the effect of 5-FU on surgical success and the associated reduction in intraocular pressure, visual acuity, the progression of the filtering bleb and necessary medication. Methods 103 not previously operated eyes with preoperative healthy cornea were included in this retrospective, non-randomised comparative study. All eyes received during trabeculectomy 5mg of 5-FU and were, according to their postoperative treatment with 5-FU, allocated in one of three groups - an untreated control group, a low-dose group (max. 35mg) or a high-dose group (more than 35mg). Occurrence, extent and duration of postoperative erosions and the presence and extent of corneal scratches during the 5-FU series were documented. The documentation also included the filtering bleb findings, visual acuity, intraocular pressure and medication preoperatively, three months and twelve months postoperatively, as well as the corneal findings after three and twelve months. Results The incidence of erosions in the high-dose group was significantly higher (81%) than in the low-dose (63%) and in the control group (10%, p = 0.046 and p = 0.002). The mean appearance of erosions was on the 21. postoperative day, on average 44% of the erosions were less than half the cornea surface and healed after an average of ten days. It was found that the erosion duration correlated moderately positively with the injected 5-FU dose until the appearance of erosions (p = 0.009). Corneal epithelopathy occurred in 90% of patients with postoperative 5-FU treatment during the injection series. Three months postoperatively, the high-dose group had significantly more corneal epitheliopathy (59%, 9% erosions) than the low-dose (29%) and the control group (10%, p = 0.001). One year after trabeculectomy only the high-dose group still showed a trend to epitheliopathy, more precisely corneal scratching (21%, p = 0,09). The filtering bleb findings were in the low-dose group after three and twelve months at best (p = 0.023 and p = 0.042). The visual acuity did not differed in the study period between the groups, in total it became worse in all three groups, but showed an improvement tendency after one year in comparison to the three-month-valu,e in the high dose group to a significant extent (p = 0.012). The mean reduction of intraocular pressure from preoperatively to three months postoperatively was 43% and from preoperatively to twelve months postoperatively 35%, the latter was in the low-dose group significantly higher (45.4%) than in the high-dose group (27.9%; p = 0.031). Good and excellent surgical successes were seen after three months at an average of 76% (70%, 80% and 78% in control, low- and high-dose group) and after twelve months at an average of 66% of the patients (60%, 87% and 50% in control, low- and high-dose group). The total topical medication, that means glaucoma medication plus surface care was after three months in the high-dose group significantly higher than in the low-dose and control group (p = 0.003 and p = 0,04). This was particularly true for surface care medication (p = 0.01 and p = 0.041). A systemic medical treatment for pressure reduction was only in the high-dose group required after three months (3.45%) and one year postoperatively only the low-dose group was without any antiglaucomatous drops. Inference Unwanted complications after 5-FU application occur more frequently with increasing dosage. However, higher doses of 5-FU are sometimes required depending on the filtering bleb findings. In high-dose therapy with 5-FU, a surgical success can still be saved in up to 50% of patients (after one year), but with an increase of side effects. A long-term damage to the epithelium by 5-FU, regardless of the dose, could not be detected. Thus, the post-operative use of 5-FU on the individual assessment of the risk-benefit ratio is warranted.
158

Einfluss der erfolgreichen Trabekulektomie auf Fluktuation und Spitzenwerte des intraokularen Druckes im Tag-Nacht-Vergleich / Influence of successful trabeculectomy to the diurnal and nocturnal maximal IOP and IOP fluctuation

Praetorius, Stefanie January 2010 (has links) (PDF)
Glaukomerkrankungen verlaufen progressiv und sind weltweit die zweithäufigste Ursa-che für Erblindung. Die einzig wirksame Therapie ist bisher die Senkung des IODs un¬ter eine individuelle Grenze. Dabei ist die Trabekulektomie diejenige Therapie mit dem stärksten drucksenkenden Effekt. Intraokulare Druckspitzen scheinen im Zusammen-hang mit progressiven Gesichtsfeldverlusten zu stehen. Die erfolgreiche Trabekulekto-mie senkt in dieser Arbeit den maximalen IOD nach einem Nachbeobachtungsintervall von 2,1 ± 1,7 Jahre auf durchschnittlich 16,0 ± 4,4 mmHg im Tagprofil und 16,0 ± 5,4 mmHg im Nachtprofil. Im Tagprofil bewirkt sie eine signifikante Senkung des maxi-malen IODs von 40 % vom präoperativen maximalen IOD (26,5 ± 5,9 mmHg), im Nachtprofil eine signifikante Senkung von 32 % des entsprechenden präoperativen Werts (23,4 ± 5,2 mmHg). Damit liegt der maximale IOD nach 2,1 ± 1,7 Jahren im Tagprofil bei 80 % der Patien-ten (bei 71 % ohne Medikamente) und im Nachtprofil bei 69 % (63 % ohne Medika-mente) unter oder bei 21 mmHg mit einer Reduktion gegenüber dem präoperativen IOD-Wertes von mindestens 20 %. Bei 60 % (54 % ohne Medikamente) im Tagprofil und bei 63 % (57 %) im Nachtprofil liegt der maximale IOD 2,1 ± 1,7 Jahre nach erfolgreicher Trabekulektomie unter 18 mmHg. Der erhöhte IOD ist nachweislich ein Risikofaktor für die Entstehung und die Progres-sion von Glaukomen. In den letzten Jahren zeigten einige Studien, dass die Fluktuation des IODs ein unabhängiger Risikofaktor für die Progression von Gesichtsfeldausfällen zu sein scheint. Die Auswirkung der erfolgreichen Trabekulektomie auf die Fluktuation ist bisher wenig untersucht. Die präoperative Fluktuation von 12,1 ± 4,2 mmHg im Tagesprofil beträgt 2,1 ± 1,7 Jahre nach erfolgreicher Trabekulektomie 5,6 ± 2,2 mmHg, das entspricht einer signifikanten Senkung von 54 % (6,5 ± 4,6 mmHg). Im Nachtprofil wurde eine Untergruppe betrachtet. Die präoperative Fluktuation von 7,1 ± 4,5 mmHg im Nachtprofil beträgt 2,1 ± 1,7 Jahre nach erfolgreicher Trabekulektomie 3,9 ± 4,1 mmHg, das entspricht einer nicht signifikanten Senkung von 46 % (3,3 ± 6,8 mmHg). Die Signifikanz in der Untergruppe wurde durch die geringe Fallzahl in der Untergruppe beeinträchtigt. Der IOD folgt einem circadianen Rhythmus. Einige Studien berichten von Unterschie-den im Tag-Nacht-Verhalten, weshalb in der vorliegenden Arbeit das Tagprofil und das Nachtprofil getrennt ausgewertet wurden. Der präoperative maximale IOD des Tagpro-fils lag 3,1 ± 6,1 mmHg (12 %) signifikant höher als der des Nachtprofils und wurde durch die erfolgreiche Trabekulektomie um 3,1 ± 6,6 mmHg (30 %) signifikant stärker gesenkt als der des Nachtprofils. Der postoperative maximale IOD war im Tag- und Nachtprofil im Durchschnitt fast identisch. In allen weiteren Auswertungen konnte kein signifikanter Unterschied im Tag-Nacht-Verhalten des IODs festgestellt werden. Antimetaboliten werden im Rahmen fistulierender Operationen zur Verminderung der natürlichen Wundheilung eingesetzt und erhöhen nachweislich die Erfolgsrate der Operation. Einige Studien haben festgestellt, dass die subkonjunktivale Applikation von Antimetaboliten ohne weitere Intervention drucksenkende Eigenschaften hat. In der vorliegenden Studie konnte dieser Effekt nicht bestätigt werden. Diese Studie liefert interessante Erkenntnisse zum Verhalten des IODs, insbesondere der Fluktuation des IODs nach erfolgreicher Trabekulektomie bei einer relativ langen Nachbeobachtungszeit. Über die Auswirkung der Trabekulektomie in Bezug auf die Fluktuation des IODs ist bisher wenig bekannt. Die Signifikanz der Ergebnisse könnte durch eine prospektive Studie mit größeren Fallzahlen erhöht werden. Eine wichtige Beschränkung der Aussagekraft der Ergebnisse liegt darin, dass das Verhalten des IODs bisher nicht an einem kontinuierlich erfassten IOD untersucht werden kann. / High intraocular pressure (IOP) is a major risk factor for glaucoma, which is among the three most prevalent causes for blindness. Trabeculectomy (TET) is widely accepted as one of the best methods in lowering the IOP. Diurnal fluctuations of the IOP seem to be an indepentent risk factor for progression in visual field loss in case of glaucoma. In this thesis the effect of successful TET on the maximal values and the fluctuations of the IOP and the influence of intra- and postoperative use of antimetabolites (mitomycin C, 5-fluoruoracil) were studied and compared between day and night. Data were acquired retrospectively from documented diurnal and nocturnal IOP-measurements of 35 patients with medicially not controlled glaucoma who underwent successful trabeculectomy at the University of Wuerzburg and who had at least one diurnal and one nocturnal measurement of IOP before and after TET. We find that successful TET reduces the mean diurnal maximal IOP (mIOP maxD) by 40% (26,5 ± 5,9 mmHg to 16,0 ± 4,4 mmHg) (p<0,001) and the mean nocturnal maximal IOP (mIOPmaxN) by 32% (23,4 ± 5,2 mmHg to 16,0 ± 5,4 mmHg) (p<0,001). The mean diurnal pressure fluctuation after successful TET is significantly reduced by 54% (12,1 ± 4,2 mmHg to 5,6 ± 2,2 mmHg) (p<0,001). To calculate the nocturnal pressure fluctuation a smaller sub-group (7 patients) had to be built, in this group the nocturnal fluctuation is reduced by 46% (7,1 ± 4,5 mmHg to 3,9 ± 4,1 mmHg) but due to the small amount of patients the reduction is not significant (p=0,270). In this sub group the reduction of the diurnal fluctuation is averaged 49% (12,0 ± 6,1 mmHg to 6,1 ± 1,6 mmHg) with marginally significance (p<0,05). There is no significant difference between the reduction of the diurnal and nocturnal fluctuation. No influence of the intra- or/and postoperative use of antimetabolites to the maximal IOP was found in this study. For future studies larger numbers of cases, ideally deploying new techniques for continuous IOD measurement are desirable.
159

En Nationell Polis : Grunden bakom en nationell polistaktik och en utvecklad bombskyddsverksamhet

Dahlberg, Ulf, Skogberg, Erik January 2004 (has links)
<p>Vi har för avsikt att redogöra för två av de utvecklingsområden som ingår i projektet ”En Nationell Polis”. Det ena är framtagandet av en nationell polistaktik vid vardagsverksamhet – farlig situation och vid insats mot folkmassa och det andra handlar om en nationell samordning av bombskyddsverksamheten. Trenden går mot en grövre brottslighet och det har visats att kriminella skyr få medel i sitt agerande. Svensk polis saknar en homogen taktik som handlar om att på ett säkert sätt hantera situationer i vardagsverksamheten som kan utvecklas till att vara farliga. Syftet med det arbete som påbörjats är att den ”vanliga” polismannen ska ges en god bastaktisk kunskap. Sedan händelserna i Göteborg under EU-toppmötet 2001 har det konstaterats att svensk polis saknar kompetens att hantera stora ordningsstöranden. Ett förslag på organisatorisk förändring på behövlig kompetens vid sådana händelser har därför arbetats fram, dessutom ska en nationell förstärkningsorganisation skapas. Bombskyddsverksamheten i Sverige saknar ett gemensamt arbetssätt och utrustningen skiftar mellan olika myndigheter. För att kunna tackla den ökade hotbilden som finns i samhället och den ökade risken för attentat ska en nationell bombskyddsverksamhet utvecklas som ska ge bättre spetskompetens när det gäller bombskydd i Sverige. Utbildningen ska förbättras och ny utrustning ska införskaffas. Organisationen blir nationell, likartad som Nationella insatsstyrkan och ett samarbete med försvaret ska ses över.</p>
160

Nationellt koncept : Lösningar som ska öka förtroendet för polisen.

Stål, André, Iseborn, Boris January 2004 (has links)
<p>Det ingår ett flertal projekt som ligger under arbetet med ”En Nationell Polis”, och vi har för avsikt att redogöra för två av dem. Det ena är framtagandet av en nationell polistaktik vid vardagsverksamhet – farlig situation och vid insats mot folkmassa och det andra handlar om en nationell samordning av bombskyddsverksamheten. Vi har för avsikt att redogöra för vad tanken bakom ”En Nationell Polis” är och vad dessa två ovan nämnda projekt innebär. För att uppnå detta har vi tagit del av material främst från Rikspolisstyrelsen på det interaktiva nätet intrapolis. Trenden går mot en grövre och grövre brottslighet och det har visats att kriminella skyr få medel i sitt agerande. Svensk polis saknar en homogen taktik som handlar om att på ett säkert sätt hantera uppkomna situationer i vardagsverksamheten som kan utvecklas till att vara farliga. Syftet med det arbete som nu påbörjats är att den ”vanliga” polismannen ska ha en god bastaktisk kompetens som kan hjälpa till i vardagsverksamheten och lösa situationer på ett nationellt kvalitetssäkrat sätt. Sedan händelserna i Göteborg under EU-toppmötet 2001 har det konstaterats att svensk polis saknar kompetens att hantera stora ordningsstöranden. Ett förslag på organisatorisk förändring vid sådana händelser har därför arbetats fram. Polismän i yttre tjänst ska utbildas i olika nivåer. En nationell förstärkningsorganisation ska skapas. En nationell bombskyddsverksamhet ska utvecklas. Dessutom ska ett samarbete med försvaret ses över.</p>

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