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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.
41

Turbulence Intensity During Low-Level Jets in the Baltic Sea / Turbulensintensitet i samband med Low-Level Jets över Östersjön

August, Thomasson January 2021 (has links)
Low-level jets (LLJs) are local wind speed maximums in the atmospheric boundary layer. In the Baltic Sea, LLJs are frequently occurring in spring and summer. It is an important phenomena to consider for wind energy parks, and changes in turbulence during the jets can effect the efficiency of said parks. In this study, the effect that offshore LLJs have on turbulence intensity (TI) is analysed and the goal is tounderstand if TI significantly changes as the jets form, and if the changes aredifferent above and below the core. The theory of shear sheltering predicts that turbulence decreases below the core of a LLJ, and it has been experimentally tested previously with various results. However, turbulence characteristics above the core ofa LLJ has not been studied before. LiDAR measurements of wind speed and TI profiles, up to 300 m, from the island of Östergarnsholm in the Baltic Sea are used. The measurements are from the period 2016-2020 and are limited to a sector with unobstructed line-of-sight to the ocean. Complete LLJ-events, which includes non-LLJ profiles before and after the actual jets, are analysed. The LLJs are found to appear in low TI conditions related to stable stratification. Mean TI increases with 38 - 47% above the core as the jets appear, and then returns to approximately the initial values after the jets disappear. Below the core, mean TI instead decreases with 14 - 19% during the jets, which is compatible with the theory of shear sheltering. For future studies it is recommend to choose a location with larger unobstructed line-of-sight to the ocean, further optimise the LLJ-finding algorithm and also analyse other turbulent quantities. / Vindmaxima på låg höj (LLJ, för eng. Low-level jets) är lokala vindhastighetsmaximum i det atmosfäriska gränsskiktet. I Östersjön är LLJs vanliga, framförallt på våren och sommaren. Det är ett viktigt fenomen att beakta för vindkraftsparker, och turbulensförändringar i samband med LLJs kan påverka effektiviteten av vindkraftverk. I denna studie analyseras effekten som LLJs över havet har på turbulensintensiteten (TI) och målet är att förstå om TI förändras närströmmarna bildas, och om förändringarna är olika ovan och under kärnan. En teori förutspår att turbulens minskar under kärnan i en LLJ, s.k. skjuvningsblockering (eng. Shear sheltering), och den har testats tidigare med varierande resultat. Turbulens ovanför kärnan i en LLJ har dock inte studerats tidigare. LiDAR-mätningar av vindhastighets och TI-profiler, upp till 300 m, vid ön Östergarnsholm i Östersjön används. Mätningarna är från perioden 2016-2020 och är begränsade till en sektor med fri siktlinje mot havet. Kompletta LLJ-event, vilket inkluderar icke-LLJ-profiler före och efter själva strömmen, analyseras. Resultatet visar att LLJs förekommer vid låga TI-förhållanden relaterade till stabil skiktning. Medel TI ökar med 38 - 47% överkärnan när strömmarna dyker upp och återgår sedan till ungefär de ursprungligavärdena efter att strömmarna försvunnit. Under kärnan minskar medel TI istället med 14 - 19% i samband med strömmarna, vilket är förenligt med skjuvningsblockerings-teorin. För framtida studier är det rekommenderat att välja en plats med större fri siktlinje till havet, ytterligare optimera identifikationen av kompletta LLJ-event och även analysera andra variabler för att karakterisera turbulensen.
42

Development of a Low-level laser therapy product for home use : With focus on function and aesthetic design

Sandström, Vendela, Klara, Westerberg January 2023 (has links)
Today, 27 out of 1000 individuals suffer from neck pain, affecting both individuals and society (Kazeminasab et al., 2022). These problems are most prevalent in the Scandinavian countries, with Sweden being one of the countries experiencing the greatest increase (Safiri et al., 2020). Non-invasive treatments for neck pain, such as low-level laser therapy, yoga, massage, aquatic therapy, and acupuncture, are already available in the market and have shown positive results (Kazeminasab et al., 2022). In this project, a handheld product with low-level laser therapy has been developed to reduce neck pain. The goal was to create a high-quality, safe, and reliable product that was aesthetically pleasing and could cover a premium market for home-use products. This thesis is produced at Luleå University of Technology in the spring semester of 2023 as a part of the Industrial Design Civil Engineering program. The project was conducted in collaboration with Ozoneair, a local company based in Luleå that specializes in producing air purifiers. The design process drew inspiration from IDEO's human-centered approach (2015) and incorporated various design methodologies to comprehend user requirements and develop a dependable product. The process encompassed three distinct phases, namely inspiration, ideation, and implementation, all of which centered around the target users. During the inspiration phase, user information was collected through contextual investigations, observations, interviews with experts, focus groups, and user testing of existing products in order to compile a comprehensive needs analysis. In the ideation phase, multiple concepts were generated and refined through iterative cycles of user testing, ultimately leading to the selection of a final concept. The chosen concept was realized in the implementation phase by creating of a digital prototype using Blender as a program, followed by the development of a full-scale physical prototype. The result is a clean and sleek product with a distinctive aesthetic that sets it apart in the market, diverging from the conventional sterile appearance often associated with medical devices. / Idag lider 27 av 1000 individer av nacksmärtor, vilket påverkar både individer och samhället i stort (Kazeminasab et al., 2022). Dessa problem är vanligast i de skandinaviska länderna, där Sverige är ett av de länder som upplever störst ökning (Safiri et al., 2020). Icke-invasiva behandlingar för nacksmärtor, såsom lågnivå laserterapi, yoga, massage, vattenterapi och akupunktur, finns redan på marknaden och har visat positiva resultat (Kazeminasab et al., 2022). I detta projekt har en handhållen produkt med low level laser thearpy utvecklats för att minska nacksmärtor. Målet var att skapa en högkvalitativ, säker och pålitlig produkt som är estetiskt tilltalande och som kan täcka en marknad för premiumprodukter för hemmabruk.  Detta examensarbete är framtaget vid Luleå tekniska universitet vårterminen 2023, som en del av civilingenjörsprogrammet Teknisk design. Projektet genomfördes i samarbete med Ozoneair, ett Luleåbaserat företag specialiserat på luftrenare. Designprocessen inspirerades av IDEOs (2015) människocentrerade process och inkluderade flera designmetoder för att förstå användarnas behov och skapa en pålitlig produkt. Processen bestod av tre faser: inspiration, idé och implementering, som alla fokuserade på potentiella användare. Inspirationsfasen gick ut på att samla information om användare genom kontextuella undersökningar, observationer, expertintervjuer, fokusgrupper och användartester av befintliga produkter, för att sedan sammanställa en behovsanalys. I idéfasen skapades och itererades olika koncept utifrån mindre användartester, vilket ledde fram till valet av ett slutgiltigt koncept. I implementeringsfasen väcktes konceptet till liv genom en digital prototyp i programmet Blender och en fullskalig fysisk prototyp. Slutprodukten är minimalistisk och avskalad, med ett unikt utseende som sticker ut på marknaden och utmärker sig från det klassiska sterila uttryck som medicintekniska produkter förknippas med.
43

Extracting Parallelism from Legacy Sequential Code Using Transactional Memory

Saad Ibrahim, Mohamed Mohamed 26 July 2016 (has links)
Increasing the number of processors has become the mainstream for the modern chip design approaches. However, most applications are designed or written for single core processors; so they do not benefit from the numerous underlying computation resources. Moreover, there exists a large base of legacy software which requires an immense effort and cost of rewriting and re-engineering to be made parallel. In the past decades, there has been a growing interest in automatic parallelization. This is to relieve programmers from the painful and error-prone manual parallelization process, and to cope with new architecture trend of multi-core and many-core CPUs. Automatic parallelization techniques vary in properties such as: the level of paraellism (e.g., instructions, loops, traces, tasks); the need for custom hardware support; using optimistic execution or relying on conservative decisions; online, offline or both; and the level of source code exposure. Transactional Memory (TM) has emerged as a powerful concurrency control abstraction. TM simplifies parallel programming to the level of coarse-grained locking while achieving fine-grained locking performance. This dissertation exploits TM as an optimistic execution approach for transforming a sequential application into parallel. The design and the implementation of two frameworks that support automatic parallelization: Lerna and HydraVM, are proposed, along with a number of algorithmic optimizations to make the parallelization effective. HydraVM is a virtual machine that automatically extracts parallelism from legacy sequential code (at the bytecode level) through a set of techniques including code profiling, data dependency analysis, and execution analysis. HydraVM is built by extending the Jikes RVM and modifying its baseline compiler. Correctness of the program is preserved through exploiting Software Transactional Memory (STM) to manage concurrent and out-of-order memory accesses. Our experiments show that HydraVM achieves speedup between 2×-5× on a set of benchmark applications. Lerna is a compiler framework that automatically and transparently detects and extracts parallelism from sequential code through a set of techniques including code profiling, instrumentation, and adaptive execution. Lerna is cross-platform and independent of the programming language. The parallel execution exploits memory transactions to manage concurrent and out-of-order memory accesses. This scheme makes Lerna very effective for sequential applications with data sharing. This thesis introduces the general conditions for embedding any transactional memory algorithm into Lerna. In addition, the ordered version of four state-of-art algorithms have been integrated and evaluated using multiple benchmarks including RSTM micro benchmarks, STAMP and PARSEC. Lerna showed great results with average 2.7× (and up to 18×) speedup over the original (sequential) code. While prior research shows that transactions must commit in order to preserve program semantics, placing the ordering enforces scalability constraints at large number of cores. In this dissertation, we eliminates the need for commit transactions sequentially without affecting program consistency. This is achieved by building a cooperation mechanism in which transactions can forward some changes safely. This approach eliminates some of the false conflicts and increases the concurrency level of the parallel application. This thesis proposes a set of commit order algorithms that follow the aforementioned approach. Interestingly, using the proposed commit-order algorithms the peak gain over the sequential non-instrumented execution in RSTM micro benchmarks is 10× and 16.5× in STAMP. Another main contribution is to enhance the concurrency and the performance of TM in general, and its usage for parallelization in particular, by extending TM primitives. The extended TM primitives extracts the embedded low level application semantics without affecting TM abstraction. Furthermore, as the proposed extensions capture common code patterns, it is possible to be handled automatically through the compilation process. In this work, that was done through modifying the GCC compiler to support our TM extensions. Results showed speedups of up to 4× on different applications including micro benchmarks and STAMP. Our final contribution is supporting the commit-order through Hardware Transactional Memory (HTM). HTM contention manager cannot be modified because it is implemented inside the hardware. Given such constraint, we exploit HTM to reduce the transactional execution overhead by proposing two novel commit order algorithms, and a hybrid reduced hardware algorithm. The use of HTM improves the performance by up to 20% speedup. / Ph. D.
44

Near surface atmospheric flow over high latitude glaciers

Parmhed, Oskar January 2004 (has links)
<p>In this thesis various descriptions of the near surface atmospheric flow over a high latitude glacier is used in an effort to increase our understanding of the basic flow dynamics there.</p><p>Through their contribution to sea-level change, mountain glaciers play a significant role in Earth’s climate system. Properties of the near surface atmospheric flow are important for understanding glacier response to climate change.</p><p>Here, the near surface atmospheric flow is studied from several perspectives including the effects of both rotation and slope. Rotation is an important aspect of most atmospheric flows and its significance for mesoscale flows have gained recognition over the last years. Similarly, the very stable boundary layer (VSBL) has lately gained interest. Within a VSBL over sloping terrain katabatic flow is known to be usual and persistent. For the present thesis a combination of numerical and simple analytical models as well as observations from the Vatnajökull glacier on Iceland have been used. The models have continuously been compared to available observations. Three different approaches have been used: linear wave modeling, analytic modeling of katabatic flow and of the Ekman layer, and numerical simulations of the katabatic flow using a state of the art mesoscale model. The analytic models for the katabatic flow and the Ekman layer used in this thesis both utilizes the WKB method to allow the eddy diffusivity to vary with height. This considerably improves the results of the models. Among other findings it is concluded that: a large part of the flow can be explained by linear theory, that good results can be obtained for surface energy flux using simple models, and that the very simple analytic models for the katabatic flow and the Ekman layer can perform adequately if the restraint of constant eddy diffusivity is relieved.</p>
45

Assessment of noise prediction methods over water for long range sound propagation of wind turbines

Mylonas, Lukas January 2014 (has links)
Wind turbine noise is a re-emerging issue in the wind industry. As the competition for sites with good wind potential on land is rising, offshore projects in coastal areas seem as a reasonable alternative to onshore. In this context offshore sound propagation is gaining more importance considering that sound will travel over longer distances on water, especially with regard to lower frequencies. Moreover different meteorological conditions that occur on sea may attenuate or enhance sound propagation on water. The prediction tools commonly used by developers are only partially taking these parameters into account. This will be investigated in this thesis.   Hence, different methods for predicting offshore wind turbine noise are going to be assessed. These methods can be divided in two approaches namely algebraic and Partial Differential Equation (PDE) based. The methods evaluated are the ISO 9613-2 standard for outdoor noise prediction, the Danish method and the Swedish method for wind turbines noise estimation over water.   For the PDE based approach, the Helmholtz Equation will be employed in order to examine different meteorological conditions and phenomena occurring over a flat reflecting surface. The experiments with the PDE include the simulation of meteorological conditions with different levels of refraction and changing ground impedance in order to take into account the effect of a shoreline. In addition a meteorological phenomenon called the low-level jet is investigated which is characterised by strong winds at relatively low altitude.   Noise prediction tools used by developers need to be able to consider these effects in order to allow for thorough planning of wind energy projects. Nonetheless, relatively more complex models such as the Helmholtz Equation require experienced users and significant computing time. Further research and development needs to be made in order to promote the wider use of noise prediction methods like the Helmholtz Equation in the wind industry.
46

Investigating the risk factors associated with low-level viremia and virological failure in HIV-1 infected children undergoing antiretroviral therapy

Gupta, Shivani 06 January 2017 (has links)
The use of antiretroviral therapy (ART) for HIV-1 treatment effectively suppresses viral replication if managed appropriately, but sometimes patients experience incomplete viral suppression with manifestation of either persistent low-level viremia (LLV) or discernible virological failure (VF). In the present study, potential risk factors associated with LLV and VF were investigated in a cohort of HIV-1 infected Kenyan children receiving ART. Drug resistant (DR) variants in children with or without LLV were examined using a next-generation sequencing-based HIV DR typing protocol. The potential association between HIV DR mutations (DRMs) and LLV and/or VF was then examined. To measure the potential impacts from other clinical and epidemiological confounding factors, a database comprising of epidemiological and clinical information from this patient cohort was established and sanitized for ensured accountability. Statistically significant correlations between the examined factors and LLV or VF were determined using chi-square test, Kaplan-Meier survival analysis, and Cox proportional hazard models. Of 293 examined patients, 20% had LLV and 22% of the selected patients progressed to VF with no significant association observed between LLV and VF. ART adherence during therapy, baseline CD4 counts, DRMs at LLV, WHO clinical stage, gender, ART therapy stage (1st/2nd line), ART drugs and co-morbidities were not significantly associated with LLV, whereas, the ART adherence, CD4 counts and co-infection with pneumonia was significantly associated with VF. This study highlights the factors predictive of VF, and the relevance of maintaining LLV in HIV-infected children. / February 2017
47

Wind and atmospheric stability characteristics over the Baltic Sea

Svensson, Nina January 2016 (has links)
In recent years there has been an increase in offshore wind energy, which poses the need for accurate wind speed estimates in the marine environment, especially in coastal areas where most wind turbines will be placed. This thesis is focused on the Baltic Sea, which is a small, semi-enclosed sea where land-sea interaction play an important role in explaining the wind patterns. Mesoscale model simulations can be used to study the marine environment, where observations are often scarce. In this thesis the Weather Research and Forecasting (WRF) model is used. In the first study simulations show that stable stratification over sea is very common in spring and summer and is associated with an increase in low-level jet occurrence and increased wind shear below 200 m, at heights where wind turbines are erected. The model performance in stable conditions is evaluated against aircraft measurements using several boundary layer parametrization schemes, and it is shown that the low-level jet height and strength is not accurately captured with any of the parametrizations. In the second study the advection of land features is investigated. From simulations, aircraft observations and satellite images it is shown that boundary layer rolls are created in the convective boundary layer over land, and advected several tens of kilometres out over sea surface, despite the stable stratification, where convective turbulence dissipates quickly. The occurrence of boundary layer rolls gives rise to horizontal wind speed variations of several meters per second over distances of kilometres, which can increase the uncertainty of short term wind speed forecasts in coastal areas with offshore flow. It is shown that mesoscale processes in and above the marine boundary layer are important in modifying the wind field in distances of at least 100 km from the coast and that models still need to be improved in order to capture these conditions. / Under de senaste decennierna har vindkraftsutbyggnaden ökat till havs, vilket innebär att det krävs tillförlitliga vindhastighetsuppskattningar över hav, särskilt i kustområden, där de flesta vindturbinerna kommer att placeras. Den här avhandlingen kommer att fokusera på Östersjön, vilket är ett relativt litet hav omgivet av landmassor, där land-hav-interaktion har en stor påverkan på vindmönstren över havet. Mesoskaliga modeller kan användas för att studera den lägre delen av den marina atmosfären. I den här avhandlingen används modellen "Weather Research and Forecasting" (WRF). I den första studien visar simuleringar att stabila förhållanden över havet är vanligt förekommande under sommar och vår, och sker i samband med en ökad förekomst av vindmaxima på låg höjd och ökad vindskjuvning under 200 m - alltså på höjder där vindkraftverk förekommer. Modellen, med flertalet gränskiktsparametriseringar, utvärderas för stabila fall mot flygplansmätningar, och resultaten visar att styrkan och höjden för vindmaxima är antingen över- eller underskattade oavsett parametrisering. I den andra studien undersöks advektiva fenomen. Simuleringar, flyplansobservationer och satellitbilder visar att avlånga rullvirvlar uppstår i det konvektiva gränsskiktet över land och advekteras flera tiotals kilometer över hav ut från kusten. Detta trots stabila förhållanden över havet, där den konvektiva turbulensen snabbt dör ut. Rullvirvlarna ger upphov till variationer i horisontell vindhastighet på flera meter per sekund över avstånd på några kilometer, vilket kan öka osäkerheten hos korttidsprognoser för vind när det är blåser från land. Sammanfattningsvis har det har visats att mesoskaliga processer i och ovanför det marina gränsskiktet har en stor inverkan på vindfältet åtminstone 100 km från kusten, och modeller behöver fortfarande förbättras för att kunna fånga dessa företeelser. / StandUp for Wind
48

A synoptic climatology of nocturnal rainfall events during May, June and July for northeast Kansas, 1950-2012

Howard, Ian M. January 1900 (has links)
Master of Arts / Department of Geography / John Harrington, Jr / Nighttime rainfall has long been thought of as an important component to the central Great Plains hydroclimate during the wettest three-month period known as the “late spring -early summer precipitation maximum.” Research has suggested that nocturnal rainfall in the region results from a phenomenon known as the nocturnal Great Plains Low-Level Jet (GPLLJ). The jet, which originates in the Gulf of Mexico, transports moisture into the Great plains during the nighttime hours and often provides fuel for nighttime convection. The climatological characteristics of nighttime rainfall, as well the configuration of the low-level winds and the mechanisms behind its formation during this three-month wet period, however; are not well understood. Using hourly rainfall data from Topeka, KS, the nighttime rainfall characteristics are examined Topeka, KS and other Kansas stations for a 63-year period from 1950-2012 for May-July. Additionally, using the NCEP/NCAR Reanalysis data, the structure and configuration of the southerly wind phenomenon was analyzed based on its horizontal and vertical characteristics for nighttime rainfall events in May, June and July. A subsequent analysis also analyzed the larger synoptic-scale environment in place for six half-month periods from May to July. The results indicate that nighttime rainfall is a major contributor to the overall moisture budget in the Great Plains, contributing close to 50% of the overall rainfall total for the three-month period. The percentage of nighttime rainfall increases from west-east across the state, as well as temporally from May to July. The southerly winds are at their strongest during May events, tends to reach its peak at 850 mb at 6z (0000LST) near south-central Oklahoma, and forms as the result of both synoptic and thermal mechanisms. The synoptic mechanisms in place that generate the a southerly wind component change by month, leading to incredible variation in terms of its characteristics during nighttime rainfall events.
49

O uso do laser de baixa intensidade em indivíduos com zumbido e sem perda auditiva / The use of low level laser in individuals with tinnitus and without hearing loss

Silva, Mirele Regina da 13 February 2019 (has links)
Introdução: Entre as queixas mais comuns dentro dos consultórios de otorrinolaringologia e fonoaudiologia, o zumbido destaca-se como uma das que geram mais incômodo ao indivíduo. Existem várias modalidades para o tratamento do zumbido, com destaque para a terapia farmacêutica, fisioterapia, psicoterapia, cirurgia, e dentre as possibilidades de intervenção, vem crescendo o interesse no uso do laser de baixa intensidade. No entanto, apesar de existir na literatura internacional artigos sobre este assunto, há inúmeras divergências quanto ao protocolo de aplicação e a eficácia desse tratamento. Proposição: Verificar o efeito da fotobiomodulação em indivíduos com sintoma de zumbido crônico sem perda auditiva. Casuística e Métodos: O estudo foi desenvolvido no Centro Auditivo Ouvir Bauru, com a aprovação do Comitê de Ética em Pesquisa e aquiescência do paciente confirmada mediante a assinatura do Termo de Consentimento Livre e Esclarecido. Os pacientes que se enquadravam nos critérios de inclusão foram divididos aleatoriamente em Grupo 1: uso do laser de baixa intensidade e Grupo 2: uso do placebo. Foi realizado anamnese com os indivíduos antes da realização da bateria de testes e os dados coletados foram anotados no prontuário do mesmo. Após entrevista, iniciou-se a bateria de exames audiológicos que incluiu: audiometria tonal, audiometria de altas frequências, imitanciometria e acufenometria para descarte de perda auditiva, questionário Tinnitus Handicap Inventory para mensurar o nível de incomodo com o zumbido pré e pós tratamento e escala visual analógica para mensurar o nível de incômodo pré e pós aplicação do laser. O protocolo de fotobiomodulação incluiu 12 sessões de laser de baixa intensidade para o Grupo 1 e placebo para o Grupo 2, utilizando 4J na veia lingual no comprimento de onda vermelho, 4J na membrana timpânica direita e esquerda, no comprimento de onda vermelho e 9J na mastoide direita e esquerda, no comprimento de onda infra-vermelho. Resultados: a amostra foi composta por 20 pacientes, sendo oito do sexo feminino e 12 do sexo masculino com média de idade de 54 anos. Não houve diferença estatística em função do grupo de intervenção e do momento de avaliação para os desfechos audiometria de altas frequências e acufenometria. A desvantagem dos indivíduos com zumbido crônico reduziu significativamente após a intervenção, independentemente da intervenção. Pode-se averiguar que a insatisfação dos indivíduos com zumbido crônico diminuiu significativamente com diferença entre as sessões iniciais e finais, independentemente do grupo de intervenção, porém, o Grupo 1 apresentou redução significativamente maior que o Grupo 2, independentemente do momento de avaliação e do número da sessão. Conclusão: Conclui-se que indivíduos com zumbido crônico reduziram a desvantagem independentemente do grupo de intervenção, e o nível de insatisfação com o zumbido nas sessões iniciais em relação as finais independentemente do momento de avaliação e do grupo de intervenção. O grupo que recebeu a fotobiomodulação melhorou mais o nível de insatisfação com o zumbido, independentemente do momento de avaliação e do número da sessão. / Introduction: Among the most common complaints within otorhinolaryngology and audiology clinics, tinnitus stands out as one of the most uncomfortable for the subject. There are several modalities for the treatment of tinnitus, with emphasis on pharmaceutical therapy, physiotherapy, psychotherapy, surgery, and among the possibilities of intervention, there is growing significance in the use of low level laser. Nevertheless, despite many articles in the international literature about this theme, there are several disagreements regarding the protocol of application and the efficacy of this treatment. Proposition: To verify the effect of laser therapy in individuals with chronic tinnitus symptom without hearing loss. Methods: The study was developed at the Centro Auditivo Ouvir - Bauru, with the acceptance of the Research Ethics Committee and patient acquiescence confirmed by signing the Informed Consent Term. Patients who suited the inclusion criteria were randomly set to Group 1: treated with low level laser and Group 2: treated with placebo laser. Anamnesis was applied with the individuals before the battery of tests and the data collected were registered in the individuals folder. after the interview, the audiological exams started, which included: tonal audiometry, high frequency audiometry, immittanciometry and acufenometry for hearing loss disposal, Tinnitus Handicap Inventory to measure the level of discomfort with tinnitus pre and post treatment and visual analogue scale to measure the level of discomfort with tinnitus pre and post laser application. The Laser Therapy protocol included 12 laser therapy sessions for Group 1 and placebo laser for Group 2, using 4J in the lingual vein in the red wavelength, 4J in the right and left tympanic membrane, in the red wavelength, and 9J in the right and left mastoid, at the infra-red wavelength. Results: the sample consisted of 20 patients, eight females and 12 males with the average of 54 years-old. There was no statistical difference in function of the intervention group and the moment of evaluation for the high frequency audiometry and acuphenometry outcomes. The disadvantage of individuals with chronic tinnitus reduced significantly after the intervention, regardless of the intervention. It can be verified that the annoyance of individuals with chronic tinnitus decreased significantly with difference between the initial and final sessions, independently of the intervention group, but Group 1 presented a greater reduction than Group 2, independently of the moment of evaluation and the number of the session. Conclusion: It was concluded that individuals with chronic tinnitus reduced the disadvantage independently of the intervention group, and the level of discontentment with tinnitus in the initial sessions according to the final ones independently of the moment of evaluation and the intervention group. The group receiving laser therapy further improved the level of tinnitus dissatisfaction, regardless of timing and session number.
50

Efeitos da fotobioestimulação por laser e LED nas células da granulação óssea / Photobiomodulation effects by laser and LED in osseous granulation cells

Cardoso, Matheus Völz 26 May 2017 (has links)
A fotobioestimulação por laser e LED é uma tendência terapêutica inovadora e não invasiva. Os efeitos fotofísicos e fotoquímicos dessa terapia geram imunomodulação, aceleram a cicatrização e angiogênese, bem como reduzem a dor. Dessa forma tem se buscado o emprego desses estímulos no tecido ósseo, porém ainda inexistem padrões definidos para obter a melhor fotobioestimulação nas células ósseas. O objetivo desse trabalho foi avaliar a capacidade da fotobioestimulação na viabilidade celular e mineralização de células da granulação óssea de ratos (rGO). Células rGO na 6ª passagem foram plaqueadas em placas de 96 poços para os ensaios de viabilidade celular (1x10³) e em placas de 24 poços para os ensaios de cicatrização de feridas in vitro (1x104), mineralização e atividade da fosfatase alcalina (FALC) (4x104). As células receberam DMEM (10% SFB) e irradiações com laser (AlGaAs- 660nm e AlGaInP-810nm) e LED (637±15nm). Os grupos experimentais foram: laser vermelho (3 e 5 J/cm²), laser infravermelho (3 e 5 J/cm²) e LED (3 e 5s), além dos grupos controles, positivo (C+) e negativo (C-, 1%SFB). Para os ensaios de mineralização e atividade de fosfatase alcalina, além do meio convencional, grupos com meio osteogênico e os mesmos tratamentos luminosos foram acrescentados. A viabilidade celular foi avaliada pelos testes do MTT e cristal violeta nos períodos de 24, 48, 72 e 96h. O ensaio de cicatrização de feridas in vitro foi avaliado por meio da porcentagem da área de fechamento da ferida nos períodos de 12, 24, 36, 48h. O teste de mineralização foi feito por meio do teste com vermelho de alizarina nos períodos de 14, 21 e 28 dias enquanto que a atividade da FALC foi medida em 7, 14 e 21 dias. A análise estatística foi realizada através dos testes ANOVA complementados por Tukey (p<0,05). Os resultados mostraram que as terapias com luz de maneira geral aumentaram a viabilidade o fechamento da ferida in vitro, principalmente os grupos laser vermelho e LED5s (p<0,05). Pode-se observar um bom desempenho do grupo LED5s no ensaio de mineralização, onde nos grupos que receberam meio osteogênico houve um efeito somatório com a ação da fotobioestimulação promovendo maior produção de nódulos in vitro. Também, as terapias com luz, estimularam a produção de nódulos mineralizados nos grupos que receberam meio convencional de forma a superar o C+ osteogênico (p<0,05), denotando uma ação de indução osteogênica a partir da fotobioestimulação. A fosfatase alcalina foi estimulada pelos tratamentos com luz no período de 7 dias (p<0,05). Em conclusão, as terapias com laser e LED foram capazes de estimular a viabilidade e migração celular e eventos de mineralização em osteoblastos, sendo que o laser vermelho e LED promoveram os melhores resultados. / Photobiomodulation by laser and LED is a new therapeutic non-invasive trend. Photophysical and photochemical effects occur in immunomodulation, acceleration of wound healing and angiogenesis and reduction of pain. These effects are desired in bone tissue but there are no defined parameters for light irradiation and no consensus for the best effect on osseous cells. The aim of this study was to evaluate photobiomodulation effects on cell viability and mineralization events of rat osseous granulation cells (rGO). Cells in 6th passage were plated in 96-well plates for viability tests (1x10³ cells), and 24-well plates for in vitro wound healing test (1x104 cells), mineralization and alkaline phosphatases (AF) activity (4x104 cells). Cells were cultured in DMEM (10% bovine fetal serum) and irradiation with lasers (AlGaAs-660nm e AlGaInP-810nm) and LED (637±15nm). Experimental groups were red laser (3 and 5 J/cm²), infrared laser (3 and 5 J/cm²), LED (3 and 5s), positive(C+) and negative controls (C-, 1% bovine fetal serum). For mineralization and AF assays, other groups with osteogenic medium and same light treatments were added. Cell viability was evaluated by MTT and crystal violet tests at 24, 48, 72 and 96h. In vitro wound healing test evaluated the percentage of wound closure area by cells migration at 12, 24, 36, 48h. Mineralization test was done by alizarin red at 14, 21 and 28 days. AF activity was measured at 7, 14 and 21 days. Statistical analysis was performed by ANOVA complemented by Tukeys test (p<0,05). Results showed that light therapies in general increased viability and wound healing closure, mostly red laser and LED5s (p<0,05). Best results in mineralization stimulation were observed for LED5s. In groups with osteogenic medium, a synergistic effect of photobiomodulation resulted in higher numbers of mineral nodules. Light groups stimulated higher mineral nodule formation than positive control (p>0.05) even in groups with regular medium, showing an osteogenic induction by light. Increased AF activity was observed at 7 days in light treatment groups (p<0,05). In conclusion, laser and LED photobiostimulation increased viability, cell migration and mineralization events in osteoblasts with best results for red laser and LED.

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