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2.
R Soc Open Sci ; 3(8): 160328, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27853612

RESUMO

In 1912, palaeontologist Arthur Smith Woodward and amateur antiquarian and solicitor Charles Dawson announced the discovery of a fossil that supposedly provided a link between apes and humans: Eoanthropus dawsoni (Dawson's dawn man). The publication generated huge interest from scientists and the general public. However, 'Piltdown man's' initial celebrity has long been overshadowed by its subsequent infamy as one of the most famous scientific frauds in history. Our re-evaluation of the Piltdown fossils using the latest scientific methods (DNA analyses, high-precision measurements, spectroscopy and virtual anthropology) shows that it is highly likely that a single orang-utan specimen and at least two human specimens were used to create the fake fossils. The modus operandi was found consistent throughout the assemblage (specimens are stained brown, loaded with gravel fragments and restored using filling materials), linking all specimens from the Piltdown I and Piltdown II sites to a single forger-Charles Dawson. Whether Dawson acted alone is uncertain, but his hunger for acclaim may have driven him to risk his reputation and misdirect the course of anthropology for decades. The Piltdown hoax stands as a cautionary tale to scientists not to be led by preconceived ideas, but to use scientific integrity and rigour in the face of novel discoveries.

3.
Methods Mol Biol ; 915: 1-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22907399

RESUMO

Scanning electron microscopy (SEM) has been almost universally applied for the surface examination and characterization of both natural and man-made objects. Although an invasive technique, developments in electron microscopy over the years has given the microscopist a much clearer choice in how invasive the technique will be. With the advent of low vacuum SEM in the 1970s (The environmental cold stage, 1970) and environmental SEM in the late 1980s (J Microsc 160(pt. 1):9-19, 1989), it is now possible in some circumstances to examine samples without preparation. However, for the examination of biological tissue and cells it is still advisable to chemically fix, dehydrate, and coat samples for SEM imaging and analysis. This chapter aims to provide an overview of SEM as an imaging tool, and a general introduction to some of the methods applied for the preparation of samples.


Assuntos
Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura/métodos , Sulfato de Cálcio/química , Simulação por Computador , Cristalização , Desidratação , Elétrons , Método de Monte Carlo , Nanopartículas/ultraestrutura , Manejo de Espécimes , Fixação de Tecidos
4.
Methods Mol Biol ; 915: 21-36, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22907400

RESUMO

The successful embedding of bone or any sample for reflected light or electron microscopy is crucial to the success of any analysis that might follow. Different materials present different embedding challenges, and here we discuss bone. Embedding is developed often as an adapted in-house protocol, and will vary from one institution to another, and is barely referenced in any detail in scientific papers. This chapter provides the protocol for bone that has proved successful at the Natural History Museum, both for reflected light and particularly for scanning electron microscopic examination.


Assuntos
Osso e Ossos/anatomia & histologia , Osso e Ossos/ultraestrutura , Luz , Microscopia Eletrônica/métodos , Inclusão em Plástico/métodos , Animais , Humanos , Pressão , Resinas Sintéticas , Coloração e Rotulagem , Propriedades de Superfície , Temperatura
5.
Nat Genet ; 41(1): 35-46, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19060910

RESUMO

Genome-wide association studies (GWAS) of longitudinal birth cohorts enable joint investigation of environmental and genetic influences on complex traits. We report GWAS results for nine quantitative metabolic traits (triglycerides, high-density lipoprotein, low-density lipoprotein, glucose, insulin, C-reactive protein, body mass index, and systolic and diastolic blood pressure) in the Northern Finland Birth Cohort 1966 (NFBC1966), drawn from the most genetically isolated Finnish regions. We replicate most previously reported associations for these traits and identify nine new associations, several of which highlight genes with metabolic functions: high-density lipoprotein with NR1H3 (LXRA), low-density lipoprotein with AR and FADS1-FADS2, glucose with MTNR1B, and insulin with PANK1. Two of these new associations emerged after adjustment of results for body mass index. Gene-environment interaction analyses suggested additional associations, which will require validation in larger samples. The currently identified loci, together with quantified environmental exposures, explain little of the trait variation in NFBC1966. The association observed between low-density lipoprotein and an infrequent variant in AR suggests the potential of such a cohort for identifying associations with both common, low-impact and rarer, high-impact quantitative trait loci.


Assuntos
Efeito Fundador , Estudo de Associação Genômica Ampla , Redes e Vias Metabólicas/genética , Parto/genética , Grupos Populacionais/genética , Característica Quantitativa Herdável , Adulto , Pressão Sanguínea , Índice de Massa Corporal , Estudos de Coortes , Dessaturase de Ácido Graxo Delta-5 , Finlândia , Genótipo , Geografia , Humanos , Linguística , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Dinâmica Populacional , Locos de Características Quantitativas/genética , Reprodutibilidade dos Testes
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