RESUMO
AIMS: To compare decay profiles of ruminant- and cattle-associated molecular markers for faecal contamination and Escherichia coli, facilitating their correct application in water quality studies. METHODS AND RESULTS: We generated decay profiles for cultivable E. coli, a general Bacteroidales genetic marker (GenBac3), ruminant markers (CF128, Rum2Bac) and cattle markers (CowM2, CowM3) using faeces-seeded mesocosms, and selected best fitting models for each decay profile. Global model fitting tested for differences between decay profiles. After normalizing for initial concentration, decay curves differed significantly between E. coli and all genetic markers except CowM3. Decay curves for CF128 differed from GenBac3 and Rum2Bac, but Rum2Bac and GenBac3 decay profiles did not differ. Despite similar survival profiles for some markers, highly varied initial concentrations affected time to nondetection. CONCLUSIONS: Decay curves and time until nondetection differed among markers from the same host. However, the Rum2Bac and GenBac3 markers had similar decay profiles and could potentially be investigated further for source allocation using the ratio method. SIGNIFICANCE AND IMPACT OF THE STUDY: As the use of genetic markers for microbial source tracking becomes increasingly common, caution is necessary. Both the shape of decay curves and time to nondetect may differ depending on the marker selected, resulting in possible misinterpretation of results and precluding application of a 'ratio method' of source allocation.
Assuntos
Monitoramento Ambiental/métodos , Água Doce/química , Qualidade da Água , Animais , Bactérias/genética , Bacteroidetes/genética , Bovinos , Escherichia coli/genética , Fezes/microbiologia , Água Doce/microbiologia , Marcadores Genéticos , Modelos Teóricos , Reação em Cadeia da Polimerase/métodos , Controle de Qualidade , Ruminantes , Microbiologia da ÁguaAssuntos
Facetas Dentárias , Estética Dentária , Processamento de Imagem Assistida por Computador/métodos , Sistemas On-Line , Clareamento Dental , Planejamento de Prótese Dentária , Relações Dentista-Paciente , Humanos , Masculino , Metacrilatos/química , Planejamento de Assistência ao Paciente , Participação do PacienteRESUMO
Smile-imaging is a new concept in dentistry that offers an impressive level of predictable and successful esthetic results. It is useful in the diagnosis, communication, and treatment phases of esthetic cases regardless of the treatment plan. Smile-imaging builds esthetics into the case instead of adding them on at the end. It is available to any dentist without having to spend time learning a computer program or investing in equipment. Full-face pictures of the patient are all that are required from the dentist.