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1.
Ambix ; 62(1): 50-71, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26173342

RESUMO

This paper is an attempt to document the early history of the quantitative chemical analysis of ceramic materials in Europe, with a specific interest in the analysis of archaeological ceramics. This inevitably leads to a study of the attempts made in Europe to imitate the miraculous material--porcelain--imported from China from the fourteenth century onwards. It is clear that before the end of the eighteenth century progress was made in this endeavor by systematic but essentially trial-and-error firing of various raw materials, culminating in the successful production of European porcelain by Böttger and von Tschirnhaus in 1709. Shortly after this, letters describing the Chinese manufacture of porcelain, and, more importantly, samples of raw and fired material, began to arrive in Europe from French Jesuit missionaries, which were subjected to intense study. Following the perfection of gravimetric methods of chemical analysis in the late eighteenth century, these Chinese samples, and samples of porcelain from various European factories, were regularly analysed, particularly by Brongniart at Sèvres. Similar work was carried out on English porcelain by Simeon Shaw and Sir Arthur Church. The origins of the chemical analysis of archaeological ceramics are still somewhat obscure, but must date to the late eighteenth or early nineteenth centuries, by the likes of Vauquelin and Chaptal.


Assuntos
Cerâmica/história , Cerâmica/química , China , História do Século XVIII
2.
Am J Phys Anthropol ; 145(3): 499-504, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21541927

RESUMO

It has become a widespread practice to convert δ(18)O(p) values measured in human and animal dental enamel to a corresponding value of δ(18)O(w) and compare these data with mapped δ(18)O(w) groundwater or meteoric water values to locate the region where the owner of the tooth lived during the formation of the enamel. Because this is a regression procedure, the errors associated with the predicted δ(18)O(w) values will depend critically on the correlation between the comparative data used to perform the regression. By comparing four widely used regression equations we demonstrate that the smallest 95% error is likely to be greater than ±1% in δ(18)O(w) , and could be as large as ±3.5%. These values are significantly higher than those quoted in some of the recent literature, and measurements with errors at the higher end of this range would render many of the published geographical attributions statistically unsupportable. We suggest that the simplest solution to this situation is to make geographical attributions based on the direct comparison of measured values of δ(18)O(p) rather than on predicted values of δ(18)O(w).


Assuntos
Esmalte Dentário/química , Emigração e Imigração , Isótopos de Oxigênio/análise , Dente , Abastecimento de Água/análise , Algoritmos , Animais , Humanos , Modelos Lineares , Isótopos de Oxigênio/metabolismo , Características de Residência , Dente/crescimento & desenvolvimento , Dente/metabolismo
3.
Am J Phys Anthropol ; 146(3): 446-56, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21959970

RESUMO

As part of the road widening scheme between London and Dover, Oxford Archaeology South uncovered a large boundary ditch of Iron Age origin that contained Iron Age and Roman inhumations, adjacent to which was a small mid-late Roman cemetery, interpreted as a rural cemetery for Romano-British farmers. Grave goods in the cemetery were restricted to a few individuals with hobnailed boots. Bulk bone collagen isotopic analysis of 11 skeletons of Iron Age and Roman date gave a typical C(3) terrestrial signal (average δ(13) C = -19.8‰, δ(15) N = 9.3‰), but also revealed one (SK12671) with a diet which included a substantial C(4) component (δ(13) C = -15.2‰, δ(15) N = 11.2‰). This is only the second such diet reported in Roman Britain. Subsequent δ(18) O(c) and (87) Sr/(86) Sr measurements on the dental enamel in this individual were, however, consistent with a "local" origin, indicating that either C(4) protein was consumed in Late Roman Britain, or that he came from somewhere else, but where conditions gave rise to similar isotopic values. If we accept the latter, then it indicates that using oxygen and strontium isotopes alone to identify "incomers" may be problematic. The provision of hobnailed boots for the dead appears to have had a strong symbolic element in Late Roman Britain. We suggest that in this case the boots may be significant, in that he was being equipped for the long march home.


Assuntos
Arqueologia/métodos , Sepultamento/história , Isótopos/análise , Mundo Romano/história , Sapatos , Adolescente , Adulto , Aminoácidos/análise , Criança , Colágeno Tipo I/química , Esmalte Dentário/química , Dieta , Inglaterra , Feminino , História Antiga , Humanos , Lactente , Masculino , Espectrometria de Massas , Proteínas de Plantas
4.
J Exp Med ; 172(1): 159-67, 1990 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2162904

RESUMO

Dendritic cells (DC) are potent accessory cells (AC) for the initiation of primary immune responses. Although murine lymphoid DC and Langerhans cells have been extensively characterized, DC from murine lung have been incompletely described. We isolated cells from enzyme-digested murine lungs and bronchoalveolar lavages that were potent stimulators of a primary mixed lymphocyte response (MLR). The AC had a low buoyant density, were loosely adherent and nonphagocytic. AC function was unaffected by depletion of cells expressing the splenic DC marker, 33D1. In addition, antibody and complement depletion of cells bearing the macrophage marker F4/80, or removal of phagocytic cells with silica also failed to decrease AC activity. In contrast, AC function was decreased by depletion of cells expressing the markers J11d and the low affinity interleukin 2 receptor (IL-2R), both present on thymic and skin DC. AC function was approximately equal in FcR+ and FcR- subpopulations, indicating there was heterogeneity within the AC population. Consistent with the functional data, a combined two-color immunofluorescence and latex bead uptake technique revealed that lung cells high in AC activity were enriched in brightly Ia+ dendritic-shaped cells that (a) were nonphagocytic, (b) lacked specific T and B lymphocyte markers and the macrophage marker F4/80, but (c) frequently expressed C3biR, low affinity IL-2R, FcRII, and the markers NLDC-145 and J11d. Taken together, the functional and phenotypic data suggest the lung cells that stimulate resting T cells in an MLR and that might be important in local pulmonary immune responses are DC that bear functional and phenotypic similarity to other tissues DC, such as Langerhans cells and thymic DC.


Assuntos
Células Dendríticas/citologia , Células de Langerhans/citologia , Pulmão/citologia , Timo/citologia , Animais , Anticorpos Monoclonais , Antígenos de Superfície/biossíntese , Adesão Celular , Separação Celular , Centrifugação com Gradiente de Concentração , Células Dendríticas/imunologia , Células de Langerhans/imunologia , Pulmão/imunologia , Teste de Cultura Mista de Linfócitos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Fagocitose , Receptores de Interleucina-2/biossíntese , Formação de Roseta , Dióxido de Silício , Timo/imunologia
5.
Am J Phys Anthropol ; 143(3): 343-54, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20949607

RESUMO

We have carried out isotopic analysis (δ(13)C and δ(15)N) on five salt-preserved bodies from the salt mine at Chehr Abad, Iran, dating from the 4th C. BC through to the 4th C. AD. In an attempt to identify the geographical origins of these people, we have analyzed over a hundred archeological bone samples from various archeological sites in Iran. From the faunal remains, we observe that the entire ecosystem appears to be enriched in (15)N, which we suggest is due to the semi-arid nature of the region. We have also observed a number of cattle remains from one site (Nargas Tepe) which have a significant C(4) component to their diet from the 4th millennium BC. By combining our data with those published by [Bocherens et al.: Environ Archaeol 5 (2000) 1-19; Bocherens et al.: J Arch Sci 33 (2006) 253-264], we suggest that two of the "mummies" may have come from the Tehran/Qazvin Plain region (i.e., relatively local to the salt mine), and a further two appear on isotopic grounds to have come from the northeast of Iran or the Turkmenistan steppes. The fifth (no. 4), the best preserved, appears to have come from further afield. Collectively, these mummies and their contexts augment our knowledge of social mobility and technical innovation in Iran during the Achaemenid period.


Assuntos
Antropologia Física/métodos , Osso e Ossos/química , Isótopos de Carbono/análise , Múmias , Isótopos de Nitrogênio/análise , Animais , Bovinos , Colágeno/química , Ecossistema , História Antiga , Cavalos , Humanos , Irã (Geográfico) , Sais , Ovinos , Suínos
6.
Arch Pathol Lab Med ; 117(12): 1225-32, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8250693

RESUMO

Understanding how lung immunity develops against pulmonary pathogens should lead to more rational approaches in vaccine design and to the use of recombinant cytokines in lung disease. T lymphocytes are central to the development of effective immune responses; therefore, understanding how lung immunity develops will require a study of how and where T cells respond to respiratory antigens. Our laboratory has helped define the phenotype and function of lung dendritic cells, which likely play an essential role in stimulating naive T cells to respond to antigens. We found that both interstitial and alveolar macrophages can regulate the function of these cells, the former to enhance activity, the latter to suppress. In addition, we developed a murine pulmonary infection model using the fungus, Cryptococcus neoformans, in which T-cell-mediated immunity is essential for effective host clearance of the organism. The role of T cells in this model is to recruit and activate effector cells to resolve the lung infection; both CD4 and CD8 T-cell subsets are required for optimal effector cell recruitment. These studies are summarized as examples of current approaches to understanding pulmonary immunity.


Assuntos
Pulmão/imunologia , Infecções Respiratórias/imunologia , Linfócitos T/imunologia , Animais , Células Dendríticas/imunologia , Modelos Animais de Doenças , Humanos , Imunidade/imunologia , Camundongos
7.
J Forensic Sci ; 40(2): 222-7, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7602282

RESUMO

Many researchers in the field of forensic odontology have questioned the error estimates stated in Gustafson's paper outlining the relationship between certain dental attributes and age. In a substantial re-working of Gustafson's data, Maples and Rice corrected Gustafson's regression statistics and found that the error associated with the age estimate was nearly double that claimed by Gustafson. We offer another statistical analysis of Gustafson's data and find that the errors calculated by Maples and Rice were also in error, being about a year too small. We give a formula for what we believe to be the correct treatment of errors in such cases, but conclude by observing that there is an urgent need for a more rigorous study of the traits first tabulated by Gustafson.


Assuntos
Determinação da Idade pelos Dentes/métodos , Odontologia Legal/métodos , Adolescente , Adulto , Humanos , Pessoa de Meia-Idade , Análise de Regressão , Reprodutibilidade dos Testes
8.
J Forensic Sci ; 41(2): 189-94, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8871375

RESUMO

Much of the data which appears in the forensic and archaeological literature is ordinal or categorical. This is particularly true of the age related indicators presented by Gustafson in his method of human adult age estimation using the structural changes in human teeth. This technique is still being modified and elaborated. However, the statistical methods of regression analysis employed by Gustafson and others are not particularly appropriate to this type of data, but are still employed because alternatives have not yet been explored. This paper presents a novel approach based upon the application of Bayes' theorem to ordinal and categorical data, which overcomes many of the problems associated with regression analysis.


Assuntos
Determinação da Idade pelos Dentes/métodos , Teorema de Bayes , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Criança , Humanos , Pessoa de Meia-Idade , Análise de Regressão
9.
J Forensic Sci ; 42(1): 10-6, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8988569

RESUMO

An HPLC method is described for simultaneously obtaining the enantiomeric ratio of three amino acids (aspartic acid, serine, and glutamic acid) from dental collagen, with a view to using this information for estimating age at death. Results are reported from a sample of twenty three known age modern teeth, six known age 19th C. AD teeth, and two unknown age Romano-British teeth. It was found (as expected) that all three D/L ratios changed significantly with chronological age. Standard calibration techniques were used to estimate ages for the six 19th C. AD specimens from regression equations estimated from the modern specimens, and also to predict (for the first time) the error associated with such estimates. Errors using aspartic acid were found to be similar to those obtained by other methods of age estimation from dental evidence, serine, and glutamic acid providing much poorer age estimates. Additionally, a systematic difference in the age-enantiomeric ratio relationship was observed between modern and older dental samples. It is concluded that there is some fundamental difference in the observed enantiomeric ratios between modern teeth and older samples, possibly as a result of the chemical alteration of the dental proteins.


Assuntos
Determinação da Idade pelos Dentes/métodos , Aminoácidos/análise , Dentina/química , Ácido Aspártico/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Colágeno/química , Antropologia Forense , Ácido Glutâmico/análise , História do Século XIX , História Antiga , História Moderna 1601- , Humanos , Modelos Lineares , Racemases e Epimerases , Serina/análise
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 57(6): 1325-38, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11419475

RESUMO

FT-Raman spectra were collected from fossil resins originating from a variety of geographical locations. The spectral profiles of most of the fossil resins could be related to modern resins containing diterpenoid components with predominantly labdane skeletons. The spectra collected from the fossil resin sample from Borneo differed from other fossil resins and was found to contain triterpenoid components. The differences in the spectral profile of fossil resins containing diterpenoid components are shown to relate to differences in level of maturation rather than geographical origin. FT-Raman spectra of fossil resins cannot be used to distinguish source although the degree of maturation can be used as an indicator to narrow the range of possible geographical origins.


Assuntos
Âmbar/análise , Bálsamos/análise , Estrutura Molecular , Análise Espectral Raman/métodos
11.
Biologist (London) ; 48(5): 213-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11584135

RESUMO

Hair removed from archaeological burials can tell us a lot about the diet and lifestyle of our ancestors--information that may survive because of the unique biology of hair formation. But hair is also biodegradable and the effects of time and burial conditions can result in conflicting evidence of past lives.


Assuntos
Arqueologia/métodos , Cabelo/química , Cabelo/anatomia & histologia , Cabelo/metabolismo , Cor de Cabelo , Humanos
12.
Br J Dermatol ; 157(3): 450-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17553052

RESUMO

BACKGROUND: Hair is degraded by the action of both dermatophytic and nondermatophytic microorganisms. The importance of understanding hair sample condition in archaeological and forensic investigation highlights the need for a detailed knowledge of the sequence of degradation in samples that have been either buried or left exposed at the ground surface. OBJECTIVES: To investigate the sequence of biodegradative change to human terminal scalp hair from archaeological and forensic contexts. METHODS: Cut modern scalp hair from three individuals with caucasoid-type hair was inoculated with soil microorganisms through soil burial in the field and under laboratory conditions to produce experimentally degraded samples. The degraded hair fibres were subjected to detailed histological examination using a combination of high-resolution light microscopy, transmission electron microscopy and scanning electron microscopy to investigate the nature and sequence of degradative change to hair structural components. RESULTS/DISCUSSION: Degradation was found to occur first within the least structurally robust components that afford the least resistance to microbial/chemical attack. The sequence of degradation (most to least-reflecting degree of vulnerability) in the hair cuticle was as follows: (1) intercellular delta-layer (cell membrane complex); (2) endocuticle; (3) cell membrane beta-layers; (4) exocuticle; (5) epicuticle; and (6) A-layer. In the hair cortex this was as follows: (I) intercellular delta-layer (cell membrane complex); (II) cell membrane beta-layers; (III) intermacrofibrillar matrix/nuclear remnants; (IV) microfibrils; (V) intermicrofibrillar matrix; and (VI) pigment granules (the hair fibre component that was the least vulnerable to degradation). CONCLUSIONS: The selective progress of degradation in the hair shaft has been charted and this provides a basis for further histological work in better understanding the condition of hair fibres derived from archaeological or forensic contexts as well as being relevant to investigation of diseased hair, in particular hair infected by dermatophytes and hair weakened by genetic hair shaft abnormalities.


Assuntos
Sepultamento/métodos , Exposição Ambiental , Antropologia Forense/métodos , Cabelo , Mudanças Depois da Morte , Animais , Feminino , Antropologia Forense/estatística & dados numéricos , Cabelo/ultraestrutura , Humanos , Masculino , Couro Cabeludo , Fatores de Tempo
13.
Reg Immunol ; 5(3-4): 151-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8240933

RESUMO

Effective pulmonary immune responses likely require both local antigen presenting cells (APC) and regulatory suppressor cells. Bronchoalveolar cells (BAC), which consist primarily of alveolar macrophages (AM), are poor APC in most species and are often suppressive. However, dendritic cell (DC)-enriched populations from both lung interstitium and BAC have potent APC activity as measured by their capacity to stimulate both alloantigen and antigen-induced lymphoproliferative T cell responses. To determine if BAC could down-regulate pulmonary immune responses, BAC were mixed with DC-enriched loosely adherent lung interstitial cells (LAd) in a mixed leukocyte reaction (MLR). With high numbers of BAC, MLRs were consistently suppressed and suppression was partially reversed by the addition of indomethacin and catalase. Supernatants from BAC cultured with either syngeneic or allogeneic T lymphocytes in the presence of indomethacin and catalase markedly suppressed an MLR, while supernatants from BAC cultured alone were inconsistently suppressive. Antibodies to TGF-beta completely reversed the BAC-T cell supernatant-induced suppression of the MLR. However, TGF-beta antibody only partially reversed BAC-induced suppression when BAC were added directly to MLR cultures that contained indomethacin and catalase, suggesting that, in addition to TGF-beta, prostaglandins, and H2O2, BAC in culture with LAd and allogeneic T cells also produced short-lived suppressive factors and/or mediated suppression by direct cell contact. Thus, resident BAC likely utilize multiple mechanisms including TGF-beta secretion to suppress intra-alveolar immune responses initiated by lung DC.


Assuntos
Líquido da Lavagem Broncoalveolar/imunologia , Células Dendríticas/imunologia , Pulmão/imunologia , Fator de Crescimento Transformador beta/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Feminino , Tolerância Imunológica , Técnicas In Vitro , Pulmão/citologia , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Linfócitos T/imunologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/farmacologia
14.
Am J Phys Anthropol ; 104(2): 259-65, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9386831

RESUMO

Accurate estimation of human adult age has always been a problem for anthropologists, archaeologists and forensic scientists. The main factor contributing to the difficulties is the high variability of physiological age indicators. However, confounding this variability in many age estimation applications is a systematic tendency for age estimates, regardless of physiological indicator employed, to assign ages which are too high for young individuals, and too low for older individuals. This paper shows that at least part of this error is the inevitable consequence of the statistical procedures used to extract an estimate of age from age indicators, and that the magnitude of the error is inversely related to how well an age indicator is correlated with age. The use of classical calibration over inverse calibration is recommended for age estimation.


Assuntos
Determinação da Idade pelo Esqueleto , Envelhecimento/patologia , Modelos Estatísticos , Paleopatologia , Adolescente , Adulto , Idoso , Antropologia/métodos , Arqueologia/métodos , Calibragem , Criança , Pré-Escolar , Medicina Legal/métodos , Humanos , Pessoa de Meia-Idade , Análise de Regressão
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