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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.
411

Arquitetura para aplica??es interativas imersivas de televis?o digital

Azevedo, Samuel Oliveira de 24 September 2012 (has links)
Made available in DSpace on 2014-12-17T14:55:18Z (GMT). No. of bitstreams: 1 SamuelOA_TESE.pdf: 3965946 bytes, checksum: 6a8d9b9ed216b68cf3f32ad57d32058f (MD5) Previous issue date: 2012-09-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In this work, we propose a new approach to Interactive Digital Television (IDTV), aimed to explore the concepts of immersivity. Several architectures have been proposed to IDTV, but they did not explore coherently questions related to immersion. The goal of this thesis consists in defining formally what is immersion and interactivity for digital TV and how they may be used to improve user experience in this new televisive model. The approach raises questions such as the appropriate choice of equipment to assist in the sense of immersion, which forms of interaction between users can be exploited in the interaction-immersion context, if the environment where an immersive and interactive application is used can influence the user experience, and which new forms of interactivity between users, and interactivity among users and interactive applications can be explored with the use of immersion. As one of the goals of this proposal, we point out new solutions to these issues that require further studies. We intend to formalize the concepts that embrace interactivity in the brazilian system of digital TV. In an initial study, this definition is organized into categories or levels of interactivity. From this point are made analisis and specifications to achieve immersion using DTV. We pretend to make some case studies of immersive interactive applications for digital television in order to validate the proposed architecture. We also approach the use of remote devices anda proposal of middleware architecture that allows its use in conjunction with immersive interactive applications / Neste trabalho, propomos uma nova abordagem para a Televis?o Digital Interativa (TVDI), visando explorar os conceitos de imersividade. V?rias arquiteturas j? foram propostas para a TVDI, mas n?o exploram coerentemente quesitos relacionados ? imers?o. O objetivo desta tese consiste em definir formalmente o que s?o a imers?o e a interatividade para a TV digital e em como elas podem ser usadas para melhorar a experi?ncia do usu?rio deste novo modelo televisivo. A abordagem do problema levanta quest?es como a escolha apropriada de equipamentos para ajudar na sensa??o de imers?o; que formas de intera??o entre os usu?rios podem ser exploradas no contexto intera??o-imers?o; se o ambiente em que uma aplica??o interativa imersiva ? utilizada influencia na experi?ncia de imers?o; e que novas formas de interatividade dos usu?rios da TVDI entre si, e entre os usu?rios e as aplica??es interativas, podem ser exploradas com o uso da imers?o. Como um dos objetivos desta proposta, apontamos solu??es novas para estas quest?es que carecem de mais estudos. Ensejamos formalizar os conceitos que abarcam a interatividade no Sistema Brasileiro de televis?o Digital. Num estudo inicial realizado, esta defini??o ? organizada em categorias ou n?veis de interatividade. A partir deste ponto, s?o feitas an?lises e especifica??es para atingir a imers?o usando a TVDI. Visionamos alguns estudos de caso de aplica??es interativas imersivas para televis?o digital, visando validar a arquitetura proposta. Tamb?m, ? abordado o uso de dispositivos remotos, e a proposta b?sica de uma arquitetura de middleware que permita sua utiliza??o em conjunto com aplica??es interativas imersivas
412

Parents' Attitudes Toward Cultural Integration in a Navajo Language Immersion School

January 2012 (has links)
abstract: Ultimately, the examples and foundation provided at home will impact the child as a student and lifelong learner. In Navajo society, there are some families who continue to instill the importance of heritage language and culture. And then there are those who choose not to, or who are not capable of doing so due to the lack of knowledge to share such teachings. Diné language and culture are vital elements of who we are as Diné. They are what identify us as a people. Our language and culture separate us from the western society. As parents and educators, our attitudes affect our homes, schools, and children. Our way of thinking may inhibit or perpetuate cultural teachings. However, no one knows how parents' attitudes affect cultural integration at an immersion school. This quantitative study examined parents' attitudes toward cultural integration in a Navajo language immersion school (Ts4hootsoo7 Diné Bi')lta' with the Window Rock Unified School District #8 in Fort Defiance, Arizona). Surveys were used to examine parents' attitudes about language and cultural integration. The survey asked about Navajo language and culture, about the extent to which it was practiced at home, and their opinions about how Navajo language and culture was being taught at school. The data were reported in basic descriptive statistics for the total group of respondents and then disaggregated by age, place of birth (on the reservation or off), gender, marital status, and highest grade completed in school. The data has shown that overall parents are supportive of Navajo language and culture. Their attitudes may vary based on age, place of birth, gender, marital status, and education. In spite of this, Navajo language and culture are in the home. However, the degree to which it is spoken or practiced is not measured. Parents are supportive of the school teaching Navajo language and culture. / Dissertation/Thesis / Ed.D. Educational Administration and Supervision 2012
413

Diegetiskt kontra icke-diegetiskt narrativ : En undersökning i hur två olika berättartekniker påverkar en spelares uppfattning och inlevelse i ett datorspel-narrativ / Diegetic contra non-diegetic narrative : A study in how a players perception and immersion of a narrative is changed based on diegetic or non-diegetic storytelling

Rapp, Marcus January 2018 (has links)
I detta arbete har det undersökts huruvida ett narrativ som berättas endast genom dieges ger samma resultat som om berättelsen skulle förmedlas med hjälp av icke-dieges. Detta arbete fokuserade på den verbala berättartekninken och genom en undersökning där sex vana spelare av narrativa spel intervjuades. Undersökningen genomfördes genom semistrukturerade intervjuer där informanterna fick spela två artefakter, en diegetisk och en icke-diegetisk. Artefakterna var utformade att leverera narrativet genom tal och språk och skapades efter Walter Murch teori om kodat och inbäddat ljud. Utvärderingen visade att alla sex deltagare kunde skapa sig en viss uppfattning om narrativet men att det med icke-dieges blev tydligare vad den exakta berättelsen var.
414

Follow the Raven : A Study of Audio Diegesis within a Game’s Narrative

Anderberg, Ted, Rosén, Joakim January 2017 (has links)
Virtual Reality is one of the next big things in gaming, more and more games delivering an immersive VR-experience are popping up. Words such as immersion and presence has quickly become buzzwords that’s often used to describe a VR-game or experience. This interactive simulation of reality is literally turning people’s heads. The crowd pleaser, the ability to look around in 360-degrees, is however casting a shadow on the aural aspect. This study focused on this problem in relation to audio narrative. We examined which differences we could identify between a purely diegetic audio narrative and one utilizing a mix between diegetic and non-diegetic sound. How to grab the player’s attention and guide them to places in order for them to progress in the story. By spatializing audio using HRTF, we tested this dilemma through a game comparison with the help of soundscapes by R. Murray Schafer and auditory hierarchy by David Sonnenschein, as well as inspiration from Actor Network Theory. In our game comparison we found that while the synthesized sound, non-diegetic, ensured that the sound grabs the player’s attention, the risk of breaking the player’s immersion also increases.
415

Serious Games and Affective Gaming : Affective avatars and the play-motivation in serious gaming

Höschele Modic, Bernard January 2017 (has links)
This study aims to explore the question, how the use of applied gaming aspects through affective gaming, specifically as affective avatars, can promote an increment in play-motivation compared to today’s serious gaming. Similar studies in different fields have already shown, that the use of serious gaming can have a very positive impact on the motivation. This study should provide an initial step towards applying serious gaming and gamification through affective computing, for a more efficient motivational educating. By combining the fun of gaming, serious part and the affective avatar gaming, a much higher informational and motivational result could be achieved. A quantitative method was used to collect the data from 18 participants, participating in the research study. The participants were separated into three groups, equally distributed between experienced video game players and non-experienced ones, playing three different game versions, including and excluding affective elements. The collected and analysed data indicates, that participants do seemingly show a slightly higher play-motivation by having an affective avatar interaction. The gained result from this study could potentially show a new path of using affective avatars in a serious gaming setting and strengthen its possible potential.
416

To do what we usually do : An ethnomethodological investigation of intensive care simulations

Sjöblom, Björn January 2006 (has links)
Simulators provide great promises of pedagogical utility in a wide array of practices. This study focuses on the use of a full-scale mannequin simulator in training of personnel at an intensive care unit at a Swedish hospital. In medicine, simulators are a means of doing realistic training without risks for the patient. Simulators for use in intensive care medicine are built to resemble as closely as possible the human physiology. In the studied sessions the simulator (a Laerdal SimMan) is set up to be an as-authentic-as-possible replication of the nurses regular, day-to-day practice. In examining the training-sessions, it was found that the participants often did other things than “proper” simulation, such as joking or making comments about the simulation. These “transgressional activities” were studied from a perspective of ethnomethodology, using video-recordings of the session. These were transcribed and analyzed in detail using ethnomethodologically informed interaction analysis. Several themes were developed from the recordings and transcripts. These have in common that they demonstrate the participants’ own achievement and maintenance of the simulation as a distinct activity. The analysis provides an account of how the local order of the simulation is upheld, how it is breached and how the participants find their way back into doing “proper” simulation. It is an overview of the interactional methods that participants utilize to accomplish the simulation as a simulation. This study concludes with a discussion of how this study can provide a more nuanced view of simulations, in particular the relation between simulated and “real” practices. Notions of realism, authenticity and fidelity in simulations can all be seen to be the participants’ own concern, which informs their activities in the simulation.
417

Respostas cardiorrespiratórias, neuromuscularese e cinéticas de exercícios de hidroginástica / Cardiorespiratory, neuromuscular and kinetic responses of water aerobic exercises

Alberton, Cristine Lima January 2011 (has links)
O objetivo do presente estudo foi analisar as respostas cardiorrespiratórias, neuromusculares e cinéticas de mulheres realizando exercícios de hidroginástica em diferentes intensidades de esforço. No estudo I, 20 mulheres jovens (24,0 ± 2,5 anos; 163,3 ± 6,7 cm; 60,0 ± 6,7 kg) realizaram quatro sessões de testes progressivos, três correspondentes aos testes aquáticos (corrida estacionária (CE), chute frontal (CF), deslize frontal (DF)) e uma correspondente ao teste em esteira terrestre (EST), com o intuito de determinar e comparar as respostas de frequência cardíaca (FC), consumo de oxigênio ( 2 VO ) e ventilação (Ve ) no primeiro limiar ventilatório (LV1), no segundo limiar ventilatório (LV2) e no máximo esforço (MAX). No estudo II, 15 participantes da amostra realizaram duas sessões, uma no meio aquático (MA) e outra no meio terrestre (MT). O protocolo de testes consistiu na execução dos três exercícios de hidroginástica nas três intensidades pré-determinadas (LV1, LV2 e MAX) com o intuito de determinar o valor de pico da força de reação do solo vertical (Fzpico) e o impulso (IMP). No estudo III, 12 participantes da amostra realizaram uma sessão correspondente ao protocolo experimental, que consistia na execução dos três exercícios de hidroginástica nas três intensidades de esforço previamente avaliadas, com o intuito de determinar as respostas de 2 VO , atividade eletromiográfica (EMG) dos músculos reto femoral (RF), semitendinoso (ST), vasto lateral (VL), porção curta do bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio lateral (GL) e a Fzpico. ANOVA para medidas repetidas de um, dois e três fatores foram utilizadas (α = 0,05). Ao comparar as respostas cardiorrespiratórias entre protocolos de testes progressivos, não foram observadas diferenças significativas entre os exercícios aquáticos para nenhuma das intensidades. No entanto, o protocolo em EST apresentou valores significativamente maiores de FC em todas as intensidades, de 2 VO nas intensidades LV2 e MAX, e de Ve na intensidade LV2. Ao analisar a força de reação do solo, respostas significativamente maiores para Fzpico e IMP foram verificadas para MT comparado a MA. Diferenças significativas foram observadas entre todas as intensidades para Fzpico e IMP no MT, e IMP no MA. Todavia, diferenças significativas foram observadas somente entre LV1 e as demais intensidades para Fzpico no MA. Além disso, no MA, valores de Fzpico significativamente menores foram observados entre o exercício DF e os demais exercícios. Para o sinal EMG, valores significativamente maiores foram observados para CF e menores para CE na atividade de todos os músculos, exceto TA que apresentou maiores respostas para DF comparado aos demais. Além disso, diferenças significativas entre as intensidades foram observadas para todos os grupos musculares. A partir dos resultados, conclui-se que, em um programa de treinamento de hidroginástica, existe a necessidade de realizar-se testes máximos específicos nos exercícios aquáticos, uma vez que as respostas de FC, 2 VO e Ve apresentaram diferenças entre os exercícios de hidroginástica analisados e EST. Outro fator a ser levado em consideração é a escolha da intensidade e dos exercícios a serem prescritos. Se o objetivo for amenizar a ação da Fzpico, exercícios com as características do DF devem ser priorizados, sendo importante salientar que o mesmo apresenta uma intensa atividade neuromuscular para todos os músculos analisados, exceto GL. Além disso, intensidades correspondentes ao LV1 devem ser utilizadas a fim de minimizar a Fzpico, todavia, nessa intensidade a atividade neuromuscular foi significativamente menor para todos os exercícios e músculos analisados. Por outro lado, se o objetivo é trabalhar com altas intensidades, não existe diferença entre a Fzpico correspondente ao esforço máximo e LV2, logo a intensidade máxima pode ser utilizada com a mesma segurança que LV2, apresentando um menor IMP e uma maior ativação EMG para todos os grupos musculares analisados. No entanto, se o objetivo for minimizar a ativação muscular, sugere-se o uso do exercício CE, uma vez que ele pode ser utilizado nas aulas de hidroginástica com a mesma intensidade cardiorrespiratória que os demais exercícios avaliados, induzindo a uma menor fadiga periférica. / The aim of the present study was to analyze the cardiorespiratory, neuromuscular and kinetic responses of women performing water aerobic exercises at different effort intensities. In study I, 20 young women (24.0 ± 2.5 years; 163.3 ± 6.7 cm; 60.0 ± 6.7 kg) performed four progressive test sessions, three corresponding to aquatic tests (stationary running (SR), frontal kick (FK), cross country skiing (CCS)) and one to treadmill (TRE), with the purpose of determining and comparing the heart rate (HR), oxygen uptake ( 2 VO ) and ventilation (Ve ) responses at the first ventilatory threshold (VT1), second ventilatory threshold (VT2) and maximal effort (MAX). In study II, a sample of 15 participants performed two sessions, one in water immersion (WI) and the other on dry land (DL). The test protocol consisted of three water aerobic exercises performed at three pre-determined intensities (VT1, VT2 and MAX) with the purpose of determining the peak vertical ground reaction forces (Fzpeak) and impulse (IMP). In study III, a sample of 12 participants performed one session corresponding to the experimental protocol, which consisted of three water aerobic exercises performed at the three previously evaluated effort intensities, with the purpose of determining the VO2 , electromyographic activity (EMG) of rectus femoris (RF), semitendinosus (ST), vastus lateralis (VL), short head of biceps femoris (BF), tibialis anterior (TA) and gastrocnemius lateralis (GL), and the Fzpeak. One-way, two-way and three-way repeated measures ANOVA were used (α = 0.05). Regarding cardiorespiratory responses to the progressive test protocols, there were no significant differences between aquatic exercises at any intensity. However, the TRE protocol showed significantly higher HR at all intensities, VO2 at intensities corresponding to VT2 and MAX, and Ve at VT2. Analyzing the ground reaction forces, significantly higher values of Fzpeak and IMP were observed for DL compared to WI. It was observed significant difference between all intensities for Fzpeak and IMP on DL, and for IMP in WI. Nevertheless, a difference was observed between VT1 and higher intensities for Fzpeak in WI. In addition, in WI significantly lower Fzpeak values were observed for CCS compared to the other exercises. Regarding the EMG signal, significantly higher muscle activity was found for the FK, and lower for the SR, except in the TA muscle, which presented higher responses for the CCS compared to the other exercises. Moreover, there were significant differences between intensities for all muscle groups. According to the results, it might be concluded that, during water aerobics training is important to perform specific maximal tests in the aquatic exercises, since the HR, VO2 and Ve responses presented differences between water aerobic exercises and TRE. Another important issue that must be considered is the exercise and intensity to be prescribed. Exercises with similar characteristics to the CCS must be priorized if the aim is to attenuate the Fzpeak action, as it is important to highlight that this exercise presents intense neuromuscular activity in all the analyzed muscles, with the exception of GL. In order to minimize the Fzpeak, intensities corresponding to VT1 must be performed. However, the neuromuscular activity was significantly lower for all exercises and muscles analyzed at VT1. On the other hand, there is no difference in the Fzpeak between MAX and VT2; thus the maximal intensity is as safe to use as the VT2, with lower IMP and higher EMG activation in all the analyzed muscle groups. Notwithstanding, if the aim is to minimize the muscular activation, SR is recommended since it can be used during water aerobics with a similar cardiorespiratory intensity to the other evaluated exercises, while inducing lower peripherical fatigue.
418

Mundos virtuais na educação : a interatividade em simulações de fenômenos físicos

Greis, Luciano Kercher January 2012 (has links)
Uma nova geração de alunos, imersos em tecnologias que envolvem a utilização de mensagens de texto, mídias sociais e games, vem surgindo a cada dia, trazendo um foco diferente, uma mentalidade e um estilo de aprendizagem distinto em relação às gerações que os precederam. Estes alunos sentem-se igualmente confortáveis aprendendo em ambientes virtuais ou reais, pois não conseguem ver a diferença que separa um mundo do outro. A experiência de uso dessas tecnologias imersivas em um ambiente educacional poderia desencadear no aluno um maior engajamento e assim favorecer os processos de aprendizagem? Esta dissertação apresenta a possibilidade de utilização de um simulador social como recurso pedagógico, apresentando o recurso de simulação educativa de um conteúdo da disciplina de Física no contexto de um mundo virtual. Podemos trazer para esta situação de ensino e aprendizagem a possibilidade de reproduzir experiências pessoais, que são certamente mais significativas do que situações em que apenas apresentamos um modelo descritivo demonstrando o fenômeno. Novas possibilidades de interação e colaboração surgem neste modelo de simulação. Para tanto, foi desenvolvido um simulador que contempla um fenômeno físico estudado no primeiro ano do ensino médio, a colisão de dois corpos. A ambientação deste simulador remete o estudante a um parque de diversões, no qual ele interage com uma de suas atrações, o Carro Choque. A simulação aqui proposta busca instigar o aluno a descobrir “o que aconteceria se”. Mais que um simulador finalizado que apenas representa o fenômeno e determina qual a resposta é a correta, este simulador tem por objetivo auxiliar o aluno a observar o fenômeno e melhor compreender os conceitos a ele associados, formular suas próprias hipóteses e conclusões, tendo preferencialmente a presença de um professor que o instigue, crie as situações problema para que este aluno busque identificar as possíveis alternativas. Para validação da pesquisa, utilizou-se o simulador em uma turma de oitava série do ensino fundamental, com o objetivo de observar evidências de aprendizagem e engajamento dos estudantes no simulador proposto. Os seis alunos envolvidos na pesquisa, de cunho qualitativo, passaram por cinco etapas de observação, seguindo metodologia com base construtivista, tendo como principais referenciais os teóricos Piaget e Inhelder e Sinclair. A partir do acompanhamento dos alunos nos experimentos, foi possível observar que este modelo simulado alcançou os objetivos inicialmente propostos. A interatividade e imersão propiciados pelo ambiente virtual proporcionam um maior nível de engajamento aos alunos envolvidos na pesquisa e se mostraram facilitadores dos processos de aprendizagem relacionados aos fenômenos físicos considerados. / A new generation of students, immersed in technologies which evolve with the use of text messages, social media and games, emerges day after day, bringing a different focus, learning mechanisms different from preceding generations. These students feel equally comfortable to learn in virtual or real environments, as they do not see the difference that separates one world from the other. The experience in the use of these immersive technologies in an educational environment could trigger in the student a higher level of engagement and in this way favor learning processes? This Masters dissertation presents an investigation about the use of a social simulator as a pedagogical resource, proposing an educational simulation resource of a topic in Physics, in the context of a virtual world. One may bring for this learning situation the possibility to reproduce personal experiences, which are certainly more significant than other situations in which a descriptive model demonstrating a given phenomenon is used. New possibilities of interaction and collaboration emerge in this simulation model. A simulator has been developed involving a physics phenomenon that is studied in the first year of high school: two-body collision. The setting chosen for the simulator was an amusement park, in which the student interacts with one of its attractions, the bumper car. The simulation proposed here attempts to instigate the student to find out “what would happen if”. More than a closed simulator that only represents the given phenomenon and determines which would be the correct answer, this simulator has as a main goal to help the student to observe the phenomenon and better understand the concepts associated to it, to formulate his/her own hypotheses and conclusions, preferably working with a teacher who can instigate him, who can create problem situations for the student to try to identify possible alternatives. To validate the research, the simulator has been used in a class with the goal of observing students’ learning and engagement evidence. The six students who participated in this qualitative research went through five observation steps, following a constructivist methodology, mainly based on the theorists Piaget, Inhelder and Sinclair. The experiments demonstrated that the simulated model achieved the proposed goals. The interactivity and immersion of the virtual world enabled a higher engagement level of the students participating in the research, and facilitated learning processes related to the physical phenomenon considered.
419

Parametrizações de superfícies triangulares

Telau, Antônio Carlos 06 September 2012 (has links)
Made available in DSpace on 2016-12-23T14:34:46Z (GMT). No. of bitstreams: 1 Antonio Carlos Telau.pdf: 9635690 bytes, checksum: a7331b14de28bbdd635032e352894361 (MD5) Previous issue date: 2012-09-06 / Two types of triangular surface parameterizations are proposed in this work: spherical and planar parameterization. We highlight among the applications of this technique, texture mapping and manipulation/deformation of surfaces. In the planar case, a surface with boundary is parameterized in a planar convex polygon, as from the planar immersion of its graph. The theory presented characterizes the set of parameterizations of a given surface, when convex polygon is fixed, from matrices which satisfy a set of conditions. In the case spherical, advanced results of graph theory are used to determine parameterizations of closed surfaces. In this case, we characterize the set of spherical parameterizations of a given surface as the set of all spherical immersions of your graph where each vertex is a spherical projection of some convex combination of its neighbors. In both cases, algorithms based on the methodology propose have been implemented and we presente some results obtained by the proposed algorithms. The results are analyzed and limitations of the algorithms are discussed / Duas classes de parametrizações de superfícies triangulares são propostas nesta dissertação: parametrizações planares e esféricas. Podemos destacar dentre as aplicações de parametrizações, mapeamento de textura e manipulação/ deformação de superfícies. No caso planar, uma superfície com bordo é parametrizada em um polígono convexo planar, a partir da imersão planar do grafo associado a superfície. A teoria apresentada caracteriza o conjunto das parametrizações de uma dada superfície, em um polígono convexo, a partir de matrizes que satisfazem um conjunto de condições. No caso esférico, resultados avançados da teoria de grafos são utilizados para determinar parametrizações de superfícies fechadas. Neste caso, caracterizamos o conjunto de parametrizações esféricas de uma dada superfície como o conjunto de todas as imersões esféricas do grafo da superfície em que cada vértice é a projeção esférica de alguma combinação convexa de seus vizinhos. Em ambos os casos, algoritmos baseados na metodologia proposta foram implementados e apresentamos alguns resultados obtidos pelos algoritmos propostos. Os resultados são analisados e as limitações dos algoritmos são discutidas
420

Desenvolvimento de hidroxiapatita contendo prata via precipitação e imersão: avaliação do efeito antimicrobiano / Development of hydroxyapatite with silver by precipitation and immersion: evaluation of antimicrobial effect

Milena Felix Bossu 08 October 2015 (has links)
A utilização de substitutos ósseos para recuperação da função perdida é uma constante busca dentro da área médica. Por isso os biomateriais têm recebido uma atenção muito grande por parte da comunidade científica, dentre eles os materiais a base de fosfato de cálcio. A hidroxiapatita, Ca10 (PO4)6 (OH) 2, tem sido muito estudada, pois além de representar a constituição da massa dos ossos naturais e dentes em 30 a 70%, possui propriedades de bioatividade e osteocondutividade, favorecendo e auxiliando o crescimento do tecido ósseo. Em contrapartida, infecções bacterianas podem surgir após o implante ocasionando a perda da funcionalidade a curto e médio prazo. Várias alternativas estão sendo testadas, geralmente associadas ao uso de antibióticos convencionais incorporados aos biomateriais. Uma alternativa a tais antibióticos seria a utilização de metais que possuem propriedades antibacterianas. A prata (Ag) é conhecida como um metal bactericida e por isso ganhou lugar de destaque dentre os estudos como um aliado importante no controle das infecções pós-cirúrgicas. Este trabalho teve como objetivo sintetizar, caracterizar e avaliar o efeito antimicrobiano da adição de íons de prata em hidroxiapatita. Foram obtidos pós de hidroxiapatita contendo prata (HAAg), nas concentrações de 0,1M; 0,01M e 0,001M pelo método de precipitação em temperatura ambiente e por imersão do pó de hidroxiapatita em soluções aquosas. As fases cristalinas e os grupamentos iônicos foram analisados para cada condição por técnicas de difração de raios X (DRX) e espectroscopia no infravermelho (IV) respectivamente. As informações sobre a morfologia e identificação de elementos químicos foi realizado pela técnica de microscopia eletrônica de varredura com espectroscopia de energia dispersiva (MEV EDS). As avaliações antimicrobianas foram realizadas por ensaios qualitativos e quantitativos, o ensaio qualitativo utilizou o teste de halo de difusão em disco para Staphylococcus aureus e Escherichia coli e o ensaio quantitativo utilizou contagem de bactérias para as cepas de Staphylococcus aureus. Os resultados de DRX e IV indicaram que independentemente do método de obtenção da HAAg foi possível observar a presença de prata metálica caracterizada pelos picos em 2θ=38,1º e 44,3º nas amostras HAAg0,1Im, HAAg0,1Pr e HAAg0,01Pr. Observou-se também a presença de AgO, correspondente ao pico em 2θ=37,5º nas amostras de HAAg0,01Pr e HAAg0,001Pr. Nos espectros de IV estão presentes as bandas que caracterizam a fase HA, referentes aos grupamentos PO43-, OH- e CO32-. Analisados em conjunto os ensaios qualitativos e quantitativos, as amostras HAAg0,01Im e HAAg0,001Im sintetizadas por imersão indicaram os melhores resultados para o ensaio de disco difusão, por apresentarem formação de halo inibição do crescimento bacteriano para a bactéria S. aureus. Para os ensaios quantitativos as amostras obtidas por precipitação com concentrações 0,1M e 0,01M de prata apresentaram melhor resultado por inibirem o crescimento bacteriano para as cepas S. aureus. / The use of bone substitutes for recovery of lost function is a constant search within the medical field. So biomaterials have received a very large attention from the scientific community, including the materials the basis of calcium phosphate. Hydroxyapatite, Ca10(PO4)6(OH)2, has been studied as apart from representing the natural constitution of the mass of bones and teeth in 30 to 70 % , has properties of bioactivity and osteoconductivity, encouraging and assisting the growth of bone tissue. In contrast, bacterial infections can arise after implantation causing the loss of functionality in the short and medium term. Several alternatives are being tested, usually associated with the use of conventional antibiotics incorporated into biomaterials. An alternative would be to use antibiotics such metals that possess antibacterial properties. Silver (Ag) is known as a bactericidal metal and so gained a prominent place among the studies as an important ally in the control of post- surgical infections. This study aimed to synthesize, characterize and evaluate the antimicrobial effect of adding silver ions into hydroxyapatite. Were obtained hydroxyapatite powders containing silver (Haag) at concentrations 0,1M; 0,01M and 0,001M by the precipitation method at room temperature and by immersion the hydroxyapatite powder in aqueous solutions of AgNO3. The crystalline phases and the ionic groups were analyzed for each condition by techniques of X-ray diffraction (XRD) and infrared spectroscopy (IR) respectively. The information on the morphology and identification of chemical elements was performed by the technique of scanning electron microscopy with energy dispersive spectroscopy (SEM EDS). The antimicrobial evaluations were carried out by qualitative and quantitative assays, the assay used a qualitative diffusion halo disk test for Staphylococcus aureus, Escherichia coli and quantitative assay employed bacteria count for Staphylococcus aureus strains. The results of XRD and IR indicated that regardless of the method of obtaining Haag was possible to observe the presence of metallic silver characterized by peaks in 2θ=38,1º and 44,3º in HAAg0,1Im samples, HAAg0,1Pr and HAAg0,01Pr. It also observed the presence of AgO, corresponding to the peak in 2θ=37,5º in samples HAAg0,01Pr and HAAg0,001Pr. In the IR spectra are present bands that characterize the HA phase, referring to groups PO43-, OH- and CO32-. Taken together qualitative and quantitative assays, and HAAg0,01Im HAAg0,001Im synthesized by soaking samples showed the best results for the disk diffusion test by presenting halo formation bacterial growth inhibition for S. aureus. For quantitative assays, the samples obtained by precipitation with concentrations 0,1M and 0,01M silver showed better results by inhibiting bacterial growth for Staphylococcus aureus strains.

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