Evaluation of the influence of artefacts caused by titanium on dental and bone structures in images acquired in CBCT with and without the metal artefact reduction tool

Orientador: Francisco Haiter NetoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O presente estudo teve como objetivo avaliar quantitativamente a interferência dos artefatos metálicos causados pelo titânio em diferentes posições e quantidade no arco dentário em imagens adquiridas nos aparelhos de TCFC Picasso Trio e OP300 Maxio nas estruturas ósseas e dentárias com e sem o uso da ferramenta de redução de artefatos (FRA). Um fantoma acrílico contendo em seu interior 8 perfurações simulando um arco dentário, cinco raízes de pré-molares inferiores permanentes e cinco blocos ósseos de uma costela bovina mantidos na mesma posição para as aquisições tomográficas, foi a área de análise para todos os protocolos. Cinco cilindros de titânio foram inseridos gradativamente nas regiões adjacentes e opostas às das raízes e blocos ósseos. Foram adquiridos 9 protocolos que diferiram em relação a distribuição e quantidade de cilindros metálicos: Controle (sem metal); A ¿ 1 metal posterior, do lado oposto a área de análise; B - 2 metais lado oposto a área de análise; C - 2 metais posteriores e 1 metal anterior lado oposto a área de análise; D - 1 metal posterior e adjacente a área de análise; E - 2 metais posteriores adjacentes à área de análise; F - 2 metais posteriores e 1 na região anterior adjacente a área de análise; G ¿1 metal na região anterior do lado oposto a área de análise; e H - 1 metal na região anterior e 1 metal na posterior, ambos do lado oposto da área de análise. Os desvios padrões dos valores de cinza ao redor dos terços radiculares dentários, osso medular e cortical foram quantificados no software ImageJ. A expressão de artefatos entre os aparelhos foi avaliada pelo teste de Wilcoxon, a expressão dos artefatos nos protocolos e ação da FRA pelo teste de Kruskal-Wallis (p<0.0001) com nível de significância de 5%. Para os dentes, o aparelho Picasso (p<0.0001) apresentou maior expressão de artefatos, independentemente da ativação da FRA e da quantidade de objetos metálicos. Para os dois equipamentos, o protocolo F apresentou a maior expressão de artefatos quando comparado com os demais protocolos para as áreas ao redor das raízes e blocos ósseos. Conclui-se com este estudo que a expressão de artefatos causados por titânio é maior quando maior a quantidade de objetos metálicos presentes nas regiões adjacentes a eles. As ferramentas de redução de artefatos se mostraram eficazes para as estruturas dentárias, porém a análise sofreu interferência direta em relação ao equipamento utilizadoAbstract: Implant surgery may be planned by means of Cone Beam Computed Tomography (CBCT). High density materials such as titanium implants produce artefacts decreasing the image quality and under or super estimating anatomical structures. This study aims to evaluate the interference of artefacts caused by titanium on the region around teeth and bone structures in images acquired in two CBCT devices considering different distances, quantity and locations in the dental arch with and without the use of the Metal Artefact Reduction (MAR) tool. Five single rooted teeth, and five bone and titanium cylinders were arranged and positioned in different locations and quantities in a PMMA phantom with perforations simulating a lower dental arch and scanned in nine different protocols (Control, A-H). Eight regions of interest around each root third, cortical and trabecular bone were used to measure the grey value standard deviation corresponding the artefact expression in the Image J software. Both the artefact expression and the MAR effect were assessed using the Wilcoxon and Kruskal-Wallis tests (significance level of 5%). For teeth, Picasso Trio (p<0.001) expressed more artefacts when compared to OP300 Maxio regardless of the MAR activation. For both devices, protocol F (3 metals on the adjacent area of the analysis region) showed higher artefact expression for bone and teeth when compared to the others. In conclusion, artefact expression caused by titanium is greater when more metal objects are positioned in the adjacent dental and bone structures in CBCT images however bone was more affected by the artefact expression when compared to teeth. The MAR seems to be effective on the adjacencies of teeth, but its action may vary from a device to anotherMestradoRadiologia OdontologicaMestre em Radiologia OdontológicaCAPE

Natural Hazards in Sao Vicente (Cabo Verde)

São Vicente island (República de Cabo Verde) lies within the Sahelian zone and faces a number of natural hazards, of which the most significant ones are erosion and gully formation, desertification and flash flooding hazards. Based on examples, we set out to examine the main factors involved in the development of these natural hazards from a regional point of view, while simultaneously assessing the importance of anthropic action as a structural factor. The investigation of Lazareto’s gullies (located to the west of Mindelo) aimed to determine the main factors of the gullies formation. It also sought to demonstrate that the gullies’ formation is a reliable indicator of the high rates of erosion on a regional scale. The approach to the desertification hazards was based on farmers’ perception related to the evolution of agricultural production, strategies to mitigate drought and desertification issues, consequences and future prospects based on a set of interviews conducted in Ribeira da Vinha. Finally, the intense rainfall event that occurred on August 26, 2008 was analysed to identify the main vulnerability factors of the city in light of the flash flood hazard

PERFORMANCE OF BRAZILIAN BUSINESS, ACCOUNTING AND TOURISM GRADUATE PROGRAMS

The Brazilian institution in charge of graduate programs (CAPES) evaluates all programs every three years, focusing on publications in scientific periodicals, which are classified by the Qualis – CAPES system. This study aims to measure the relative efficiency of post-graduate programs in Business, Accounting and Tourism through Data Envelopment Analysis (DEA) and to measure the change in productivity from the three-year period of 2004-2006 to the 2007-2009 period by the Malmquist Index. Efficiencies of some graduate programs in Brazil using DEA have been evaluated but the Malmquist Index was not used because the 2007-2009 data was only recently available. They also used different input and output variables and did not consider, in our view, the real importance CAPES attributes to publications. We used, as inputs, professors, dissertations and thesis and, as outputs, total points obtained from the Qualis classification of periodicals. Among the results: the efficiency increased from the first to the second period; the efficiency of public institutions was higher as was the efficiency of programs with PhD courses and of programs more than 12 years old; the Malmquist index increased from one triennium to another

Estratégias competitivas das lojas de departamentos: o caso da RENNER S/A

TCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Economia.Este trabalho não possui resumo

O jornal e o jornalista de amanhã

The article emphasizes the importance of the newspaper, as a company, and of the journalist, as a professional, being aware of the challenges which appear and also of the resulting search for new mana-gement methods and processes. Furthermore, it stresses the importance that regional journalism has taken on and the need for this practice to turn itself more to the community, to education and, therefore, to extrapolating the view one has of the reader as a mere information consumer, to see him as a citizen, a partner in the elaboration and reflection on the facts that are transmitted.O artigo ressalta a importância de o jornal, enquanto empresa, e de o jornalista, enquanto profissional, estarem atentos para os desafios que se apresentam e a decorrente busca de novos métodos e processos de gerenciamento. Trata também da importância que adquiriu o jornalismo regional e a necessidade dessa prática voltar-se mais para a comunidade, para a educação, extrapolando a visão que se tem do leitor como mero consumidor de informação, para vê-lo como cidadão, parceiro na elaboração e reflexão dos fatos noticiados

Population structure of the broad-snouted caiman (Caiman latirostris) in natural and man-made water bodies associated with a silvicultural landscape

The broad-snouted caiman (Caiman latirostris) is a South American crocodilian with a wide geographical distribution. Water bodies originally occupied by the species have suffered extreme anthropogenic pressure; however, the broad-snouted caiman has a high adaptive capacity to colonize man-made habitats such as decanting pounds and artificial reservoirs for agriculture or livestock. In this context, the present study aimed at identifying the population structure of the broad-snouted caiman in a silvicultural landscape in southeastern Brazil. Fifty-two caimans of various classes were captured with baited traps and steel cable snares at night. The estimated population size was 51 individuals. The population density was estimated to be 2.6 individuals/ha with a linear density of 11.3 individuals/km. The intermediate values of linear density estimates herein compared with other areas, suggesting that silvicultural landscapes can be relevant for broadsnouted caiman conservation. Therefore, the role of silvicultural landscapes in crocodilian conservation should be taken into consideration for environmental certification processes related to forestry in the Neotropics.Fil: Marques, Thiago Simon. Universidade de Sao Paulo; BrasilFil: Bassetti, Luís Antonio Bochetti. Universidade de Sao Paulo; BrasilFil: Lara, Neliton Ricardo Freitas. Universidade de Sao Paulo; BrasilFil: Millan, Cristian Honora. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Piña, Carlos Ignacio. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Verdade, Luciano Martins. Universidade de Sao Paulo; Brasi