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"Avaliação da eficácia dos protocolos de tomografia computadorizada na identificação de lesões na mandíbula com interferência de artefatos metálicos dentários" / Efficacy evaluation of computed tomography protocols in mandibular lesions assessment with metallic artifacts interferenceAndreia Perrella 04 May 2006 (has links)
A tomografia computadorizada (TC) é a técnica de escolha para o exame de afecções da cavidade bucal e estruturas anexas, pois permite visualização de tecidos moles e duros em um único exame sem sobreposição de imagens. Este exame oferece um significativo avanço no que se refere à definição de lesões maxilo-faciais, apresentando uma excelente resolução anatômica. Porém um dos problemas que ocorre com a TC, é o aparecimento de artefatos devido a restaurações metálicas dentárias, Estes artefatos atrapalham a interpretação das imagens, dificultando a visualização de lesões. O propósito deste estudo foi avaliar a validade de dois protocolos de TC, em cortes axiais, na observação de lesões simuladas na mandíbula e a influência dos artefatos dentários metálicos. Foram realizadas TCs, em dois protocolos, de mandíbulas secas, nas quais foram executadas perfurações simulando lesões. As imagens foram realizadas em dois momentos: na presença e na ausência de restaurações dentárias metálicas. Dois observadores, previamente calibrados, observaram as imagens de acordo com diversos critérios. Como resultado observouse que a sensibilidade e a especificidade para detecção de lesões foram de 100% nos dois protocolos, porém a detecção do número de lojas das lesões multiloculares e a determinação da localização precisa e invasão precoce para medular, obteve valores menores na determinação de sua validade, sendo estes significativamente influenciados pela presença de artefatos e a espessura de corte da aquisição da imagem. / Computed tomography is the choice technique to access oral and maxillofacial lesions, because it provides hard and soft tissues visualization in one examination without superimposition of surrounding structures. This examination offers a significative advance in maxillofacial lesions definition, with an excellent anatomic resolution. However, dental metal artifacts can be a problem in the interpretation of CT images. These artifacts lead to misinterpretations of the images, making difficult to visualize lesions in these areas. The aim of this research was to evaluate the validity of two protocols, in axial sections, in simulated mandibular lesions assessment, and the influence of dental metallic artifacts in these observations. Two CT protocols were obtained from dry mandibles in which perforations were done simulating lesions. CT was performed in two moments: With and without metallic dental restorations. Two observers, previously calibrated, evaluated the images according different parameters. As results we can observe that the sensibility and specificity in lesion detection were 100% for both protocols, but the detection of loci number of multilocular lesions; location and detection of medular invasion, obtained reduced values in their validity, and this values were significantly influenced by the artifacts presence and the slice thickness of image acquisition.
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A case study of nurses information and communication needsMannerhagen, Anders January 2009 (has links)
The role of information technology within health care is getting more central and prominent. The purpose of this change is both to make the health care more efficient and to heighten patient safety. This exploratory case study of four care units aims to provide a glimpse into the clinical work of nurses, and to indentify and describe their communication and information needs. The analytical framework used in this study is distributed cognition and the research method used is cognitive ethnography. The study provides a peek into the complex system of health care, and how the central artifacts such as patient records, whiteboards and different alarm systems are used in this context. The result of the study describes the current work practices and information flows in the studied care units. From these results general system design implications are made.
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More Than Just Empty Space: Integrated Geoarchaeological Investigations of the Crystal River Site (8CI1) PlazaDelgado, Alexander C. 30 October 2017 (has links)
Crystal River (8CI1) is a Woodland period archaeological site on the west-central Gulf Coast of Florida, famous for its diverse suite of exotic artifacts typical of the Hopewell Interaction Sphere, as well as its monumental shell mounds which surround a central plaza. Historically, these plazas are utilized as spaces for cultural expression, daily interactions between members of the community, economic exchanges, and discourse of all types. They also serve as a symbolic space, embodying social and political relations that are critical to the formation and maintenance of cultural identity. These spaces are challenging to study using conventional archaeological techniques since they were often swept clean and kept free of debris, thus discouraging the possibility of recovering artifacts of any significant size. Instead, my study utilizes integrated geoarchaeological techniques, such as microartifact analysis, soil chemical analysis, ground-penetrating radar, and magnetic survey in order to reconstruct plaza activities.
The results indicate a stark difference in function between the northern and southern ends of the plaza. The South Plaza demonstrates high concentrations of elements associated with food preparation and consumption, particularly P, Sr, K, and M, high microartifact densities, and an associated strong magnetic anomaly. On the other hand, phosphate depletion is observed in the North Plaza, and it is generally barren of micro-artifacts, despite the possible presence of a few geophysical anomalies. This area appears to have been kept free of debris, save for a charcoal deposit and elevated K and Mg directly in front of Mound H, which may allude to ceremonial or other functions not associated with food.
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Forensic Analysis of G Suite Collaborative ProtocolsMcCulley, Shane 09 August 2017 (has links)
Widespread adoption of cloud services is fundamentally changing the way IT services are delivered and how data is stored. Current forensic tools and techniques have been slow to adapt to new challenges and demands of collecting and analyzing cloud artifacts. Traditional methods focusing only on client data collection are incomplete, as the client may have only a (partial) snapshot and misses cloud-native artifacts that may contain valuable historical information.
In this work, we demonstrate the importance of recovering and analyzing cloud-native artifacts using G Suite as a case study. We develop a tool that extracts and processes the history of Google Documents and Google Slides by reverse engineering the web applications private protocol. Combined with previous work that has focused on API-based acquisition of cloud drives, this presents a more complete solution to cloud forensics, and is generalizable to any cloud service that maintains a detailed log of revisions.
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Finding digital forensic evidence when graphic design applications are used for document counterfeitingMabuto, Enos Kudakwashe January 2013 (has links)
Graphic design applications are often used for the editing and design of digital art. The same applications can be used for creating counterfeit documents such as identity documents (IDs), driver’s licenses or passports, among others. The products of graphic design applications, however, leave behind traces of digital information which can be used during a digital forensic investigation. Although current digital forensic tools are designed to scrutinise systems with the purpose of finding digital evidence, the tools are not designed to examine such systems specifically for the purpose of identifying counterfeit documents.
This dissertation reviews the digital evidence relating to the creation of counterfeit documents and gathered from graphic design applications. Digital evidence gathered in this way consists mainly of identifying and corroborating the counterfeiting events that occurred on a particular system. Firstly, such an analysis is accomplished by establishing linkages between the digital forensic information that has been gathered and the specific actions that were performed when the counterfeit documents were created. Such actions comprise scanning, editing, saving, and printing. The researcher is able to compile a dossier of the digital forensic information that is generated by such actions by analysing the files that were generated by making use of a particular graphic design application for document creation. Secondly, the researcher extends the analysis to the actual files created by the application user. These files can be used as evidence to establish linkages between the content of the counterfeit documents that are being investigated and the document editing actions that are necessary for creating such documents. The researcher gathers digital forensic information of this kind by analysing the different file types that are associated with these applications. The researcher then gathers the associated timeline evidence separately by means of a third analysis that identifies timestamps from the application’s system files and evidence files. The researcher is then able to draw a timeline from the timestamps to illustrate the sequence of events that occurred. From the digital evidence gathered in this way it is possible to propose a two-pronged counterfeiting investigation process. This proposed investigation process is application and platform independent. The researcher concludes the study by transforming the model into a working prototype by demonstrating how the prototype is capable of analysing and extracting digital forensic information from certain graphic design application file types and log files. Such a prototype is capable of identifying the system that was utilised for counterfeiting particular documents or identifying whether a specific document is counterfeited or not. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Computer Science / unrestricted
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Les outils de gestion, transporteurs et régulateurs des logiques institutionnelles : cas de deux organisations de capital-risque solidaire / Management artifacts, carriers and regulators of institutional logics : two case studies of venture capital funds solidarity orientedChâteau Terrisse, Pascale 14 November 2013 (has links)
La théorie néo institutionnelle permet de penser les outils de gestion dans la société et dans l'interaction avec les acteurs des organisations. Ce travail montre la complexité des instruments de gestion et les envisage tour à tour comme : des éléments symboliques neutres à l'activité de l'organisation adoptés par souci de légitimité et diffusés par des mécanismes isomorphiques, des objets rhétoriques porteurs de langage et de catégorisations et transformés par les acteurs organisationnels, des artefacts transportant des logiques institutionnelles multiples naissant dans le champ organisationnel. Cette thèse pose l'existence d'un nouveau rôle pour les outils de gestion, celui de régulateur des contradictions entre logiques institutionnelles. Sur le plan empirique, avec une méthodologie qualitative mêlant approches longitudinales multi niveaux et recherche intervention, les logiques institutionnelles du champ de la finance solidaire en France et de deux organisations de capital-risque solidaire sont analysées. Les outils de gestion de ces deux organisations sont étudiés. Les outils créés avec le chercheur, les pactes d'actionnaires et les chartes, véhiculent les logiques institutionnelles des fonds. Le changement des pactes d'actionnaire et les comités d'investissement permettent de révéler que les outils de gestion gèrent les tensions entre logiques institutionnelle en les éliminant, les compartimentant ou les intégrant. Les résultats de cette étude permettent de discuter le degré d'incompatibilité entre les logiques en fonction de leur perméabilité, des métiers représentés dans les organisations et des pratiques considérées. Ils autorisent également une formalisation des liens entre outils de gestion et logiques institutionnelles ainsi qu'entre logiques institutionnelles présentes dans l'organisation et rôle des outils de gestion. Enfin, un process socio technique d'hybridation de logiques institutionnelles est proposé. / Institutional theory describes management artifacts as embedded in the society and in interactions with organizational actors. This work is aiming to grasp the complexity of management apparatus and analyzes it as: first, symbolical element neutral for the organizational activity, adopted for legitimacy and diffused by isomorphic mechanisms; then, rhetorical objects generating languages and categorizations, transformed by actors; finally, as artifacts carrying multiple institutional logics. This thesis postulates that management artifacts can also regulate contradictions between institutional logics. A qualitative methodology combining longitudinal multi-level approaches and research action, is revealing the institutional logics of the organizational field of interdependent finance and of two interdependent venture capital funds. The management apparatus of these funds is studied. New management tools created during the research action, charters and shareholders' agreements are carrying venture organizations' institutional logics. A change in a shareholders' agreement and the management system of the investment decision-making process in a venture fund, named investment committees, divulge that management apparatus handle tensions between institutional logics by eliminating one of them, compartmenting or integrating them. The results of this study acknowledge different degrees in the contradictions between institutional logics related to their permeability, the professions represented in the organization, the practices looked at. They contribute also to formalize links between management artifacts and institutional logics. We lastly propose a model combining two processes that explicate how multiple logics can blend and how tensions can be handled.
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Influência do uso da ferramenta de redução do artefato no diagnóstico de fraturas radiculares verticais em exames de tomografia computadorizada de feixe cônico : estudo in vitro / Influence of an artifact reduction tool on the diagnosis of vertical root fractures in teeth with metal postsBezerra, Ilana Sanamaika Queiroga, 1984- 26 August 2018 (has links)
Orientadores: Deborah Queiroz de Freitas França, Gláucia Maria Bovi Ambrosano / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T13:33:44Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: O objetivo neste trabalho foi verificar a influência da ferramenta para redução de artefato (FRA) na qualidade da imagem e no diagnóstico de FRVs, em dentes com pino metálico intracanal. A amostra foi composta por trinta dentes unirradiculares, que tiveram suas coroas removidas e seus canais instrumentados. Do total, foram induzidas fraturas completas e incompletas em vinte raízes e ao final, todas as raízes foram divididas em três grupos: controle (n=10), fratura radicular completa (n=10) e fratura radicular incompleta (n=10). Cada raiz recebeu um pino metálico intracanal e foi escaneada duas vezes no tomógrafo Picasso Trio 3D® (Vatech, Hwaseong, Coreia do Sul): uma sem e uma com o emprego da FRA. As imagens foram avaliadas objetiva e subjetivamente. A avaliação objetiva foi feita no ImageJ (NIH, Bethesda, MD, EUA), em uma região de interesse circular padronizada, na qual foram mensuradas os valores médios e a variação dos tons de cinza e a taxa contraste-ruído (TCR) nas imagens com e sema FRA. A avaliação subjetiva foi realizada de duas formas: inicialmente, cinco avaliadores (cirurgiões-dentistas, especialistas em Radiologia Odontológica) treinados analisaram as imagens no software EZ3D quanto à presença de FRV, utilizando uma escala de cinco pontos: Posteriormente, um avaliador quantificou os artefatos formados. Foram avaliados o cupping, as bandas hipodensas e as estrias hiperdensas. A imagem obtida com FRA foi comparada à sua respectiva sem FRA para atribuição de um dos três escores: (0) não houve mudança na quantidade de artefato formado; (1) houve diminuição e (2) houve aumento. As concordâncias intra e interexaminador foram avaliadas pelo teste Kappa ponderado. A comparação dos resultados do diagnóstico de FRV com o padrão-ouro foi realizada pela curva ROC (Receive Operating Characteristic). Além disso, também foram calculados os valores de sensibilidade, especificidade e acurácia. A comparação dos resultados da análise objetiva, dos valores das áreas sob a curva ROC e dos testes de diagnóstico nas aquisições com e sem a FRA foi realizada por meio do Teste t. A presença de artefatos foi avaliada por análise descritiva. Os resultados mostraram diminuição significativa dos valores médios dos tons de cinza (p=0,002) e da TCR (p=0,000) com utilização da FRA. Quanto à avaliação subjetiva, os valores das áreas sob a curva ROC, sensibilidade, especificidade e acurácia também foram inferiores com a utilização da FRA, sendo os dois últimos estatisticamente significativos, para os casos de fratura incompleta (p=0,028 e p=0,037, respectivamente) e fratura completa (p=0,021 e p=0,031, respectivamente). Em relação aos artefatos avaliados, de uma maneira geral houve diminuição dos mesmos nas imagens com FRA. Dessa forma, concluiu-se que a utilização da FRA causou uma diminuição nos artefatos formados, porém não houve não houve melhora na qualidade da imagem avaliada de maneira objetiva nem repercussão no diagnóstico de FRVs em raízes com pino metálico intracanal, uma vez que o mesmo foi prejudicado / Abstract: This study aimed to verify the influence of the artifact reduction algorithm in the image quality and the diagnosis of VFR. The sample was composed of thirty single-rooted teeth, which the crown was removed and the root canal was prepared. In twenty roots, fractures were induced. The roots were divided into three groups: control (n=10), complete (n=10) and incomplete (n=10) VRF. In each root canal it was inserted a well-fitted metal post and it was scanned in the Picasso Trio 3D® CBCT device (Vatech, Hwaseong, South Korea) with and without the artifact reduction algorithm. The images were evaluated objective- and subjectively. The objective evaluation was performed in the ImageJ software (NIH, Bethesda, MD, USA), by a standard round region of interest, on which it was measured the mean value of the grey level and contrast-to-noise ratio (CNR). Five observers (oral radiologists) performed blindly the subjective evaluation in EZ3D software to diagnosis VRF, which was classified according to a 5-point scale. Posteriorly, one observer quantified the presence of the beam hardening artifacts. It was evaluated the cupping artifacts, hypodense halos and streak artifacts. The images with and without the artifact reduction algorithm was compared according three scores: no change, increase or decrease of the beam hardening artifact. The intra- and interobserver agreement were calculated by the weighted-Kappa test. The ROC (Receiver Operating Characteristic) curve was used to compare the diagnosis of VRF and the gold standard. Also, the sensitivity, specificity and accuracy were obtained. The comparison of the grey levels and the CNR were performed by the t-Test. The production of beam hardening artifacts was descriptive analyzed. The results showed a significant decrease of the grey level (p=0,002) and CNR (p=0,000) with the artifact reduction algorithm. The ROC curve values, sensitivity, specificity and accuracy were lower with the artifact reduction algorithm for the diagnosis of VRF. It was observed a statistically significant difference in the specificity and accuracy. Regarding to the quantity of the beam hardening artifacts, it was observed an overall reduction in images with the artifact reduction algorithm. In conclusion, the use of the artifact reduction algorithm produced a decrease of the beam hardening artifacts; however, it was observed negative influence in image quality and in the diagnosis of VRF in the presence of metal post / Doutorado / Radiologia Odontologica / Doutora em Radiologia Odontológica
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Influência da ferramenta de redução de artefato metálico na qualidade de imagens de TCFC = Influence of metal artefact reduction tool in quality of CBCT images / Influence of metal artefact reduction tool in quality of CBCT imagesQueiroz, Polyane Mazucatto, 1991- 08 June 2015 (has links)
Orientador: Deborah Queiroz de Freitas França / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-28T02:05:09Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Resumo: Materiais de alta densidade física e alto número atômico quando presentes no objeto escaneado podem resultar em artefato nas imagens tomográficas. O artefato compromete a qualidade da imagem tomográfica, podendo inviabilizar o uso dessa modalidade de diagnóstico. Com este trabalho, teve-se dois objetivos: avaliar a ação da ferramenta de redução de artefato metálico (RAM) nas imagens tomográficas de phantoms com diferentes materiais utilizados na Odontologia (amálgama de prata, guta-percha e liga metálica) e avaliar a influência de diferentes tamanhos de campo de visão (field of view - FOV) e de voxel sobre a ação da ferramenta. Foram confeccionados três phantoms de resina acrílica com amostras dos materiais estudados em seu interior. Os phantoms foram escaneados no tomógrafo do aparelho Picasso Trio® (Vathec, Hwaseong, Coréia do Sul) com diferentes FOVs (120x85 mm, 80x80 mm, 80x50 mm e 50x50 mm) e voxels (0,3 mm e 0,2 mm). Todos os escaneamentos foram realizados duas vezes com cada parâmetro, uma sem ativação e uma com ativação da ferramenta de RAM. As imagens foram avaliadas no programa OnDemand3D (CyberMed, Seul, Coréia do Sul). Foram obtidos valores de média e desvio-padrão do histograma das áreas ao redor das amostras e das áreas-controle e foi calculada a relação contraste-ruído (RCR). Os dados foram submetidos à análise. Observou-se influência positiva da ferramenta nos valores do desvio-padrão das áreas ao redor das amostras dos materiais amálgama de prata e liga metálica. Não houve influência da utilização da ferramenta sobre os valores das médias e valores de RCR. Na presença da ferramenta de RAM, o FOV e o voxel não influenciaram os valores de desvio-padrão das áreas ao redor das amostras. Foi possível concluir que a ferramenta mostrou-se eficaz na redução do artefato gerado pelo amálgama de prata e pela liga metálica; e a ação da ferramenta não é influenciada por diferentes FOVs e voxels, de forma que esses parâmetros podem ser selecionados de acordo com o objetivo do exame, sem haver alterações quando a ferramenta é utilizada / Abstract: High density and high atomic number materials are scanned results in artefact in tomographic image. The artefact compromises the quality of tomographic image, which may make the image useless for the diagnosis. The aim of this study were: to assess the action of metal artefact reduction (MAR) algorithm on tomographic images of phantoms with different materials used in Dentistry (dental amalgam, gutta-percha and dental alloy); to assess the influence of different sizes of field of view (FOV) and voxel on the action of the MAR algorithm. Three phantoms were made of acrylic resin with the dentals materials in their interior. The phantoms were scanned on Picasso Trio® machine (Vathec, Hwaseong, South Korea) with different FOVs (120x85 mm, 80x80 mm, 80x50 mm and 50x50 mm) and voxels (0.3 mm and 0.2 mm). All scans were performed twice with each parameter, without and with activation of the MAR algorithm. The images were evaluated on the OnDemand3D software (CyberMed, Seoul, South Korea). The mean and variation (standard deviation - SD) of greyscale values of the histogram of the areas around samples and control areas were obtained. The contrast-to-noise ratio (CNR) was calculated. Data were statistically analyze. There was positive influence of the algorithm on the SD of the areas around the samples of dental amalgam and dental alloy. There was no influence of the algorithm on the mean of greyscale values and CNR. The FOV and voxel did not influence the SD of the areas around the samples when the MAR algorithm was active. In conclusion, the MAR algorithm showed positive effect in reducing the artefact caused by dental amalgam and dental alloy; its action was not influenced by different FOVs and voxels, so those parameters can be selected according to the examination purpose, as there are no changes in the algorithm use / Mestrado / Radiologia Odontologica / Mestra em Radiologia Odontológica
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Modersmålens inkludering i förskolans verksamhet : En studie om förskollärares metoder, kunskaper och erfarenheter i inkluderingsarbetet av modersmål i förskolan / The inclusion of the mother tounge in preschool : A study about preschool teachers methods, knowledge and experiences regarding the incluison work of mother tounge in preschoolGullberg, Ebba January 2021 (has links)
Sveriges förskolor är idag präglade av många olika språk vilket har gjort att förskollärare har fått ett bredare ansvar när det handlar om barns språkutveckling. Forskning visar på att det är av fördel och viktigt att barn med annat modersmål än svenska ska få möjlighet att utöva sitt eget språk i verksamheten, då det i sin tur leder till att barnet kan utveckla och förstå det svenska språket snabbare och lättare. Min studie syftar till att få ökad kunskap om hur förskollärare som arbetar inom förskolan arbetar inkluderande i miljö och i den dagliga verksamheten med fokus på modersmål. Hur de gör för att synliggöra olika språk i verksamheten och vad för pedagogiska artefakter de använder som en stöttning i kommunikation eller bara som en stöttning för barn med annat modersmål än svenska. Det sociokulturella perspektivet är en utgångspunkt i min studie då lärande sker i sociala sammanhang och språket är ett viktigt verktyg för alla människor. För att få in mycket breda och många svar som möjligt har gjort en kvantitativ studie i form av en enkätundersökning där förskollärare har fått möjlighet att delta. Studiens resultat visar att artefakter så som tecken som stöd och bildstöd är två vanliga och betydande redskap att använda sig av som komplement i barns utveckling och lärande. / Sweden’s preschools today are characterized by many different languages, which has means that preeschool teachers have been given a broader responsibility when it comes to children’s language development. Research shows that it is beneficial and important that children with a mother tounge other than swedish should have the opportunity to practice their own language in the activity, as this in turn leads to the child being able to develop and understand the swedish language faster and easier. My study aims to get more knowledge about how educators who work in pre-school works inclusievly in the environment and daily activites with a focus on mother tongue. How they do to make different languages visible in the preschool and what pedagogical artifacts they use as a support in communication or just as a support for children with a mother tongue other than swedish. The socio-cultural perspective is a starting point in my study as learning takes place in social contexts and language is an important tool for all people. In order to get as broad and as many answers as possible, I have conducted a quantitative study in the form of a questionnaire survey which preschool teachers have been given the opportunity to participate. The results of the study shows that artifacts such as signs as a support and picture-support are two imporant and significant tools to use as a complement in children’s development and learning.
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Restored interlaced volumetric imaging increases image quality and scanning speed during intravital imaging in living mice / インターレース撮像データからの立体情報復元手法開発によるマウス生体イメージングの画質およびスキャンスピードの向上Sogabe, Maina 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22376号 / 医博第4617号 / 新制||医||1043(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 松田 道行, 教授 林 康紀, 教授 江藤 浩之 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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