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1.
Nat Ecol Evol ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300260

RESUMO

Southern Africa has one of the longest records of fossil hominins and harbours the largest human genetic diversity in the world. Yet, despite its relevance for human origins and spread around the globe, the formation and processes of its gene pool in the past are still largely unknown. Here, we present a time transect of genome-wide sequences from nine individuals recovered from a single site in South Africa, Oakhurst Rockshelter. Spanning the whole Holocene, the ancient DNA of these individuals allows us to reconstruct the demographic trajectories of the indigenous San population and their ancestors during the last 10,000 years. We show that, in contrast to most regions around the world, the population history of southernmost Africa was not characterized by several waves of migration, replacement and admixture but by long-lasting genetic continuity from the early Holocene to the end of the Later Stone Age. Although the advent of pastoralism and farming substantially transformed the gene pool in most parts of southern Africa after 1,300 BP, we demonstrate using allele-frequency and identity-by-descent segment-based methods that the ‡Khomani San and Karretjiemense from South Africa still show direct signs of relatedness to the Oakhurst hunter-gatherers, a pattern obscured by recent, extensive non-Southern African admixture. Yet, some southern San in South Africa still preserve this ancient, Pleistocene-derived genetic signature, extending the period of genetic continuity until today.

2.
Sci Rep ; 14(1): 12180, 2024 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886480

RESUMO

Cornaux/Les Sauges (Switzerland, Late Iron Age) revealed remnants of a wooden bridge, artifacts, and human and animal skeletal remains. The relationship between the collapsed structure and the skeletal material, whether it indicates a potential accident or cultural practices, remains elusive. We evaluate the most plausible scenario for Cornaux based on osteological, taphonomic, isotopic, and paleogenomic analysis of the recovered individuals. The latter amount to at least 20 individuals, mostly adult males. Perimortem lesions include only blunt force traumas. Radiocarbon data fall between the 3rd and 1st c. BCE, although in some cases predating available dendrochronological estimates from the bridge. Isotopic data highlight five to eight nonlocals. No close genetic relatedness links the analyzed skeletons. Paleogenomic results, the first for Iron Age Switzerland, point to a genetic affinity with other Central and Western European Iron Age groups. The type of skeletal lesions supports an accidental event as the more plausible explanation. Radiocarbon data and the demographic structure of the sample may suggest a sequence of different events possibly including executions and/or sacrifices. Isotopic and paleogenomic data, while not favoring one scenario over the other, do support earlier interpretations of the last centuries BCE in Europe as a dynamic period from a biocultural perspective.


Assuntos
Arqueologia , Humanos , Suíça , Masculino , História Antiga , Adulto , Feminino , Fósseis , Osso e Ossos , Datação Radiométrica
3.
Nat Ecol Evol ; 7(8): 1315-1330, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37524799

RESUMO

Sambaqui (shellmound) societies are among the most intriguing archaeological phenomena in pre-colonial South America, extending from approximately 8,000 to 1,000 years before present (yr BP) across 3,000 km on the Atlantic coast. However, little is known about their connection to early Holocene hunter-gatherers, how this may have contributed to different historical pathways and the processes through which late Holocene ceramists came to rule the coast shortly before European contact. To contribute to our understanding of the population history of indigenous societies on the eastern coast of South America, we produced genome-wide data from 34 ancient individuals as early as 10,000 yr BP from four different regions in Brazil. Early Holocene hunter-gatherers were found to lack shared genetic drift among themselves and with later populations from eastern South America, suggesting that they derived from a common radiation and did not contribute substantially to later coastal groups. Our analyses show genetic heterogeneity among contemporaneous Sambaqui groups from the southeastern and southern Brazilian coast, contrary to the similarity expressed in the archaeological record. The complex history of intercultural contact between inland horticulturists and coastal populations becomes genetically evident during the final horizon of Sambaqui societies, from around 2,200 yr BP, corroborating evidence of cultural change.


Assuntos
Arqueologia , Evolução Cultural , Humanos , Brasil , Genômica
4.
Gut Liver ; 17(4): 505-515, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37305948

RESUMO

There is growing evidence of the role of fungal microbiota in the pathogenesis of inflammatory bowel disease (IBD). Fungi can exert direct pro-inflammatory effects or modify the bacterial composition via interkingdom interactions. Although several studies have demonstrated alterations in the fecal fungal microbiota composition in IBD, there is a wide variation in the mycobiome in different populations, with no definite pattern that can define the mycobiome in IBD having yet been identified. Recent work has suggested that characterizing the fecal fungal composition may influence therapeutic decisions and help to predict outcomes in a subset of IBD patients. In this study, we review the current literature on the emerging role of the fecal mycobiome as a potential tool for precision medicine in IBD.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Micobioma , Humanos , Medicina de Precisão , Doenças Inflamatórias Intestinais/microbiologia , Fezes
5.
PLoS One ; 18(2): e0281089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36791072

RESUMO

During the Late Holocene, hunter-gatherer interaction networks significantly grew in intensity and extension across Patagonia. Although this growth is evidenced by the increased flow of exotic items across the region, the mechanisms behind these strengthening social networks remain unclear. Since evidence suggests that some individuals might have performed long-distance trips, this article aims to address the potential relationship between these individuals and the flows of exotic items in North Patagonia. We analyzed 54 enamel teeth for strontium isotopes and reconstructed their probable mobility using mixed-effect models and isotope-based geographic assignments. We inferred population and individual mobility trends and compared them against the flow of exotic items built from a standardized compilation. Our results indicate that most individuals have isotopic composition compatible with residence within their burial and surrounding areas. However, a few individuals show isotopic composition incompatible with their burial areas, which suggests axes -from the burial location to the most likely isotope integration area- of extraordinary mobility. At the same time, the flows of exotic items overlap with these axes around the eastern sector of the study area suggesting that this location could have been a central point of convergence for people and items. We argue that small-scale socially driven mobility could have played a relevant role as a general mechanism of interaction that fostered and materialized Patagonian interaction networks during the Late Holocene.


Assuntos
Isótopos de Estrôncio , Dente , Humanos , Argentina , Isótopos de Estrôncio/análise , Dente/química , Sepultamento
7.
Artigo em Inglês | MEDLINE | ID: mdl-36420740

RESUMO

BACKGROUND AND OBJECTIVES: The last decade has seen a new era of classifications of asthma pathophysiology which have changed the treatment options available. To update the figures of prevalence of T2 asthma, comorbidities, biomarker characterization and costs of severe asthma in patients≥12-years-old adapted to this new situation. METHODS: Retroprospective, observational, nationwide study using a top-down approach. Data were obtained from the BIG-PAC®, an electronic medical record database of 1.7 million patients in Spain. Patients≥12-years-old who had received medical care during the period 2016-2017 and diagnosed with asthma at least one year prior to the index date were included and followed for one year. RESULTS: Prevalence of asthma was 5.5%. Of these patients, asthma was severe in 3.031 (7.7%), 81.2% of whom presented T2 asthma. Among severe asthma patients, 64·1% were uncontrolled, 31.2% were Oral corticosteroids-dependent (37% in the uncontrolled severe asthma group) and only 3.8% were on biologics. The most common T2 comorbidities were allergic rhinitis (66·1%), atopic dermatitis (29·1%) and chronic rhinositis with nasal polyps (14.6%). Mortality rates in the total and the uncontrolled severe asthma groups were 4.2% and 5.5% respectively. The total annual costs per patient with severe asthma were 5.890€ (uncontrolled) and 2.841€ (controlled). CONCLUSIONS: In the era of biologics, most severe asthma patients present T2 asthma. Despite the availability of new treatments, the rates of uncontrolled and oral corticosteroids-dependent patients with severe asthma remain high, but biologics still underused. The costs of uncontrolled severe asthma are twice as high as those of controlled severe asthma.

8.
Adv Exp Med Biol ; 1384: 255-264, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36217089

RESUMO

Automated analysis of the blood oxygen saturation (SpO2) signal from nocturnal oximetry has shown usefulness to simplify the diagnosis of obstructive sleep apnea (OSA), including the detection of respiratory events. However, the few preceding studies using SpO2 recordings have focused on the automated detection of respiratory events versus normal respiration, without making any distinction between apneas and hypopneas. In this sense, the characteristics of oxygen desaturations differ between obstructive apnea and hypopnea episodes. In this chapter, we use the SpO2 signal along with a convolutional neural network (CNN)-based deep-learning architecture for the automatic identification of apnea and hypopnea events. A total of 398 SpO2 signals from adult OSA patients were used for this purpose. A CNN architecture was trained using 30-s epochs from the SpO2 signal for the automatic classification of three classes: normal respiration, apnea, and hypopnea. Then, the apnea index (AI), the hypopnea index (HI), and the apnea-hypopnea index (AHI) were obtained by aggregating the outputs of the CNN for each subject (AICNN, HICNN, and AHICNN). This model showed a promising diagnostic performance in an independent test set, with 80.3% 3-class accuracy and 0.539 3-class Cohen's kappa for the classification of respiratory events. Furthermore, AICNN, HICNN, and AHICNN showed a high agreement with the values obtained from the standard PSG: 0.8023, 0.6774, and 0.8466 intra-class correlation coefficients (ICCs), respectively. This suggests that CNN can be used to analyze SpO2 recordings for the automated diagnosis of OSA in at-home oximetry tests.


Assuntos
Aprendizado Profundo , Síndromes da Apneia do Sono , Apneia Obstrutiva do Sono , Adulto , Humanos , Redes Neurais de Computação , Oximetria , Oxigênio , Polissonografia , Síndromes da Apneia do Sono/diagnóstico , Apneia Obstrutiva do Sono/diagnóstico
9.
Proc Natl Acad Sci U S A ; 119(43): e2109315119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36252021

RESUMO

The characterization of Neandertals' diets has mostly relied on nitrogen isotope analyses of bone and tooth collagen. However, few nitrogen isotope data have been recovered from bones or teeth from Iberia due to poor collagen preservation at Paleolithic sites in the region. Zinc isotopes have been shown to be a reliable method for reconstructing trophic levels in the absence of organic matter preservation. Here, we present the results of zinc (Zn), strontium (Sr), carbon (C), and oxygen (O) isotope and trace element ratio analysis measured in dental enamel on a Pleistocene food web in Gabasa, Spain, to characterize the diet and ecology of a Middle Paleolithic Neandertal individual. Based on the extremely low δ66Zn value observed in the Neandertal's tooth enamel, our results support the interpretation of Neandertals as carnivores as already suggested by δ15N isotope values of specimens from other regions. Further work could help identify if such isotopic peculiarities (lowest δ66Zn and highest δ15N of the food web) are due to a metabolic and/or dietary specificity of the Neandertals.


Assuntos
Carnívoros , Homem de Neandertal , Dente , Oligoelementos , Animais , Carbono/análise , Isótopos de Carbono/análise , Colágeno , Esmalte Dentário/química , Dieta , Isótopos de Nitrogênio/análise , Oxigênio/análise , Espanha , Estrôncio/análise , Dente/química , Oligoelementos/análise , Zinco/análise , Isótopos de Zinco/análise
10.
PLoS One ; 17(8): e0271296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36001535

RESUMO

Ancient written sources show that Roman funerary rituals were relevant along the entire Roman Republic and Empire, as they ensured the protection of deities and the memory of the deceased. Part of these rituals consisted of funerary offerings and banquets that were held on the day of the burial, in festivities and other stipulated days. The faunal remains recovered inside the graves and around them are evidence of these rituals. Therefore, their study can allow us to know if the funerary meals and rituals developed in the Roman necropolis were special and implied food that differed from everyday dietary habits, according to the importance of these rituals. To test this, we analysed the archaeozoological and anthropological material from the necropolis of Vila de Madrid (Barcelona, Catalonia), which was in use between the first half of the 2nd century AD and mid 3rd century AD. The archaeozoological analysis of the faunal remains recovered in the necropolis and inside the graves, as well as carbon and nitrogen stable isotope ratios results on bone collagen from 50 faunal specimens and 41 humans, suggest that, overall, funerary meals in Vila de Madrid necropolis did not imply different food than that consumed during life. Regarding age, sex, offerings and diet, some differences are observed, suggesting that inequalities present in life could have been also present in the funerary rituals.


Assuntos
Sepultamento , Mundo Romano , Dieta/história , História Antiga , Humanos , Refeições , Isótopos de Nitrogênio , Mundo Romano/história
11.
PNAS Nexus ; 1(4): pgac148, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36714834

RESUMO

Dental calculus preserves oral microbes, enabling comparative studies of the oral microbiome and health through time. However, small sample sizes and limited dental health metadata have hindered health-focused investigations to date. Here, we investigate the relationship between tobacco pipe smoking and dental calculus microbiomes. Dental calculus from 75 individuals from the 19th century Middenbeemster skeletal collection (Netherlands) were analyzed by metagenomics. Demographic and dental health parameters were systematically recorded, including the presence/number of pipe notches. Comparative data sets from European populations before and after the introduction of tobacco were also analyzed. Calculus species profiles were compared with oral pathology to examine associations between microbiome community, smoking behavior, and oral health status. The Middenbeemster individuals exhibited relatively poor oral health, with a high prevalence of periodontal disease, caries, heavy calculus deposits, and antemortem tooth loss. No associations between pipe notches and dental pathologies, or microbial species composition, were found. Calculus samples before and after the introduction of tobacco showed highly similar species profiles. Observed interindividual microbiome differences were consistent with previously described variation in human populations from the Upper Paleolithic to the present. Dental calculus may not preserve microbial indicators of health and disease status as distinctly as dental plaque.

12.
FEMS Microbes ; 3: xtac006, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37332506

RESUMO

The oral cavity is a heterogeneous environment, varying in factors such as pH, oxygen levels, and salivary flow. These factors affect the microbial community composition and distribution of species in dental plaque, but it is not known how well these patterns are reflected in archaeological dental calculus. In most archaeological studies, a single sample of dental calculus is studied per individual and is assumed to represent the entire oral cavity. However, it is not known if this sampling strategy introduces biases into studies of the ancient oral microbiome. Here, we present the results of a shotgun metagenomic study of a dense sampling of dental calculus from four Chalcolithic individuals from the southeast Iberian peninsula (ca. 4500-5000 BP). Interindividual differences in microbial composition are found to be much larger than intraindividual differences, indicating that a single sample can indeed represent an individual in most cases. However, there are minor spatial patterns in species distribution within the oral cavity that should be taken into account when designing a study or interpreting results. Finally, we show that plant DNA identified in the samples is likely of postmortem origin, demonstrating the importance of including environmental controls or additional lines of biomolecular evidence in dietary interpretations.

13.
Sci Rep ; 11(1): 24185, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921192

RESUMO

This paper presents the earliest evidence for the exploitation of lignite (brown coal) in Europe and sheds new light on the use of combustion fuel sources in the 2nd millennium BCE Eastern Mediterranean. We applied Thermal Desorption/Pyrolysis-Gas Chromatography-Mass Spectrometry and Polarizing Microscopy to the dental calculus of 67 individuals and we identified clear evidence for combustion markers embedded within this calculus. In contrast to the scant evidence for combustion markers within the calculus samples from Egypt, all other individuals show the inhalation of smoke from fires burning wood identified as Pinaceae, in addition to hardwood, such as oak and olive, and/or dung. Importantly, individuals from the Palatial Period at the Mycenaean citadel of Tiryns and the Cretan harbour site of Chania also show the inhalation of fire-smoke from lignite, consistent with the chemical signature of sources in the northwestern Peloponnese and Western Crete respectively. This first evidence for lignite exploitation was likely connected to and at the same time enabled Late Bronze Age Aegean metal and pottery production, significantly by both male and female individuals.

14.
Sci Adv ; 7(47): eabi7038, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34788096

RESUMO

The emerging Bronze Age (BA) of southeastern Iberia saw marked social changes. Late Copper Age (CA) settlements were abandoned in favor of hilltop sites, and collective graves were largely replaced by single or double burials with often distinctive grave goods indirectly reflecting a hierarchical social organization, as exemplified by the BA El Argar group. We explored this transition from a genomic viewpoint by tripling the amount of data available for this period. Concomitant with the rise of El Argar starting ~2200 cal BCE, we observe a complete turnover of Y-chromosome lineages along with the arrival of steppe-related ancestry. This pattern is consistent with a founder effect in male lineages, supported by our finding that males shared more relatives at sites than females. However, simple two-source models do not find support in some El Argar groups, suggesting additional genetic contributions from the Mediterranean that could predate the BA.

15.
Cancers (Basel) ; 13(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203269

RESUMO

The increasing mortality rates of cholangiocarcinoma (CCA) registered during the last decades are, at least in part, a result of the lack of accurate non-invasive biomarkers for early disease diagnosis, making the identification of patients who might benefit from potentially curative approaches (i.e., surgery) extremely challenging. The obscure CCA pathogenesis and associated etiological factors, as well as the lack of symptoms in patients with early tumor stages, highly compromises CCA identification and to predict tumor development in at-risk populations. Currently, CCA diagnosis is accomplished by the combination of clinical/biochemical features, radiological imaging and non-specific serum tumor biomarkers, although a tumor biopsy is still needed to confirm disease diagnosis. Furthermore, prognostic and predictive biomarkers are still lacking and urgently needed. During the recent years, high-throughput omics-based approaches have identified novel circulating biomarkers (diagnostic and prognostic) that might be included in large, international validation studies in the near future. In this review, we summarize and discuss the most recent advances in the field of biomarker discovery in CCA, providing new insights and future research directions.

16.
World J Gastroenterol ; 27(24): 3556-3567, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34239269

RESUMO

Chronic infections due to hepatitis B and hepatitis C viruses are responsible for most cases of hepatocellular carcinoma (HCC) worldwide, and this association is likely to remain during the next decade. Moreover, viral hepatitis-related HCC imposes an important burden on public health in terms of disability-adjusted life years. In order to reduce such a burden, some major challenges must be faced. Universal vaccination against hepatitis B virus, especially in the neonatal period, is probably the most relevant primary preventive measure against the development of HCC. Moreover, considering the large adult population already infected with hepatitis B and C viruses, it is also imperative to identify these individuals to ensure their access to treatment. Both hepatitis B and C currently have highly effective therapies, which are able to diminish the risk of development of liver cancer. Finally, it is essential for individuals at high-risk of HCC to be included in surveillance programs, so that tumors are detected at an early stage. Patients with hepatitis B or C and advanced liver fibrosis or cirrhosis benefit from being followed in a surveillance program. As hepatitis B virus is oncogenic and capable of leading to liver cancer even in individuals with early stages of liver fibrosis, other high-risk groups of patients with hepatitis B are also candidates for surveillance. Considerable effort is required concerning these strategies in order to decrease the incidence and the mortality of viral hepatitis-related HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Hepatite Viral Humana , Neoplasias Hepáticas , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/prevenção & controle , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Hepatite Viral Humana/complicações , Hepatite Viral Humana/epidemiologia , Humanos , Recém-Nascido , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/prevenção & controle , Fatores de Risco
17.
J Hum Evol ; 156: 102985, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34051612

RESUMO

Neanderthals are known primarily from their habitation of Western Eurasia, but they also populated large expanses of Northern Asia for thousands of years. Owing to a sparse archaeological record, relatively little is known about these eastern Neanderthal populations. Unlike in their western range, there are limited zooarchaeological and paleobotanical studies that inform us about the nature of their subsistence. Here, we perform a combined analysis of carbon and nitrogen stable isotopes on bone collagen and microbotanical remains in dental calculus to reconstruct the diet of eastern Neanderthals at Chagyrskaya Cave in the Altai Mountains of Southern Siberia, Russia. Stable isotopes identify one individual as possessing a high trophic level due to the hunting of large- and medium-sized ungulates, while the analysis of dental calculus also indicates the presence of plants in the diet of this individual and others from the site. These findings indicate eastern Neanderthals may have had broadly similar subsistence patterns to those elsewhere in their range.


Assuntos
Arqueologia , Cavernas , Dieta/história , Homem de Neandertal , Plantas , Animais , História Antiga , Humanos , Isótopos/análise , Federação Russa
18.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33972424

RESUMO

The oral microbiome plays key roles in human biology, health, and disease, but little is known about the global diversity, variation, or evolution of this microbial community. To better understand the evolution and changing ecology of the human oral microbiome, we analyzed 124 dental biofilm metagenomes from humans, including Neanderthals and Late Pleistocene to present-day modern humans, chimpanzees, and gorillas, as well as New World howler monkeys for comparison. We find that a core microbiome of primarily biofilm structural taxa has been maintained throughout African hominid evolution, and these microbial groups are also shared with howler monkeys, suggesting that they have been important oral members since before the catarrhine-platyrrhine split ca. 40 Mya. However, community structure and individual microbial phylogenies do not closely reflect host relationships, and the dental biofilms of Homo and chimpanzees are distinguished by major taxonomic and functional differences. Reconstructing oral metagenomes from up to 100 thousand years ago, we show that the microbial profiles of both Neanderthals and modern humans are highly similar, sharing functional adaptations in nutrient metabolism. These include an apparent Homo-specific acquisition of salivary amylase-binding capability by oral streptococci, suggesting microbial coadaptation with host diet. We additionally find evidence of shared genetic diversity in the oral bacteria of Neanderthal and Upper Paleolithic modern humans that is not observed in later modern human populations. Differences in the oral microbiomes of African hominids provide insights into human evolution, the ancestral state of the human microbiome, and a temporal framework for understanding microbial health and disease.


Assuntos
Evolução Biológica , Ecologia/métodos , Hominidae/microbiologia , Metagenoma/genética , Microbiota/genética , Boca/microbiologia , África , Animais , Bactérias/classificação , Bactérias/genética , Biofilmes , Placa Dentária/microbiologia , Geografia , Gorilla gorilla/microbiologia , Hominidae/classificação , Humanos , Pan troglodytes/microbiologia , Filogenia
19.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33419922

RESUMO

Although the key role of long-distance trade in the transformation of cuisines worldwide has been well-documented since at least the Roman era, the prehistory of the Eurasian food trade is less visible. In order to shed light on the transformation of Eastern Mediterranean cuisines during the Bronze Age and Early Iron Age, we analyzed microremains and proteins preserved in the dental calculus of individuals who lived during the second millennium BCE in the Southern Levant. Our results provide clear evidence for the consumption of expected staple foods, such as cereals (Triticeae), sesame (Sesamum), and dates (Phoenix). We additionally report evidence for the consumption of soybean (Glycine), probable banana (Musa), and turmeric (Curcuma), which pushes back the earliest evidence of these foods in the Mediterranean by centuries (turmeric) or even millennia (soybean). We find that, from the early second millennium onwards, at least some people in the Eastern Mediterranean had access to food from distant locations, including South Asia, and such goods were likely consumed as oils, dried fruits, and spices. These insights force us to rethink the complexity and intensity of Indo-Mediterranean trade during the Bronze Age as well as the degree of globalization in early Eastern Mediterranean cuisine.


Assuntos
Arqueologia/métodos , Cálculos Dentários/química , Alimentos/história , Ásia , Povo Asiático , Comércio/história , DNA Mitocondrial , Análise de Alimentos/métodos , Fósseis , Genoma Humano , História Antiga , Migração Humana/história , Humanos , Oriente Médio
20.
J Radiol Prot ; 41(1)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33406511

RESUMO

Working Group (WG) 6 'Computational Dosimetry' of the European Radiation Dosimetry Group promotes good practice in the application of computational methods for radiation dosimetry in radiation protection and the medical use of ionising radiation. Its cross-sectional activities within the association cover a large range of current topics in radiation dosimetry, including more fundamental studies of radiation effects in complex systems. In addition, WG 6 also performs scientific research and development as well as knowledge transfer activities, such as training courses. Monte Carlo techniques, including the use of anthropomorphic and other numerical phantoms based on voxelised geometrical models, play a strong part in the activities pursued in WG 6. However, other aspects and techniques, such as neutron spectra unfolding, have an important role as well. A number of intercomparison exercises have been carried out in the past to provide information on the accuracy with which computational methods are applied and whether best practice is being followed. Within the exercises that are still ongoing, the focus has changed towards assessing the uncertainty that can be achieved with these computational methods. Furthermore, the future strategy of WG 6 also includes an extension of the scope toward experimental benchmark activities and evaluation of cross-sections and algorithms, with the vision of establishing a gold standard for Monte Carlo methods used in medical and radiobiological applications.


Assuntos
Proteção Radiológica , Radiometria , Estudos Transversais , Método de Monte Carlo , Nêutrons , Doses de Radiação
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