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1.
Artigo em Inglês | MEDLINE | ID: mdl-38809266

RESUMO

PURPOSE: This study aims to evaluate the validity and reliability of tubomanometry (TMM) in diagnosing obstructive Eustachian tube dysfunction (OETD) before balloon Eustachian tuboplasty (BET). METHODS: A prospective cohort study was conducted, involving 25 patients with sinonasal pathology, 75 patients with middle ear disease, and 25 healthy subjects, totaling 250 ears. All participants underwent comprehensive physical examinations, including TMM, nasal videoendoscopy, otoendoscopy, Valsalva maneuver (VM), tympanometry, and audiometry. Additionally, various scales such as ETDQ-7 and ETS-7 were employed. Tympanometry served as the gold standard for assessing OETD, and comparisons were made among the measures across the three groups. RESULTS: Among the 125 participants, 44.8% (n = 56) were female, and 55.2% (n = 69) were male, with ages ranging from 19 to 93 years (M = 48.5; SD = 15.6). In our study, VM demonstrated high sensitivity (86.3%) when tympanometry was considered the gold standard. Conversely, TMM, ETDQ-7, and ETS-7 exhibited high specificity, with ETDQ-7 showing the highest specificity (87.4%). Regarding TMM, all R values in patients within the middle ear disease group were pathological (R > 1). CONCLUSION: TMM has exhibited notable specificity as a diagnostic tool compared to tympanogram and VM. Nonetheless, the combination of TMM and ETDQ-7 has enabled us to conduct a diagnostic assessment with high sensitivity and specificity for chronic OETD diagnosis.

2.
Sci Rep ; 13(1): 17103, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37919365

RESUMO

This paper explores the nature and extent of conflict in Late Neolithic Europe based on expanded skeletal evidence for violence from the San Juan ante Portam Latinam rockshelter in present-day Spain (ca. 3380-3000 cal. BC). The systematic osteological re-examination has identified 65 unhealed and 89 healed traumas-of which 77 were previously undocumented-consistent with aggression. They affect 23.1% of the 338 individuals represented. Adolescent and adult males are particularly affected (44.9% of the 107 identified), comprising 97.6% of unhealed trauma and 81.7% of healed trauma recorded in individuals whose sex could be estimated and showing higher frequencies of injuries per individual than other demographic subgroups. Results suggest that many individuals, essentially men, were exposed to violence and eventually killed in battle and raids, since warriorship is mainly restricted to this demographic in many societies. The proportion of casualties is likely to have been far greater than indicated by the 10.1% individuals exhibiting unhealed trauma, given the presence of isolated cases of unhealed postcranial trauma and of arrowheads potentially having impacted into soft tissues. This, together with skeletal indicators of poor health and the possible socioeconomic outcomes evidenced in the region, suggest wider social impacts, which may relate to a more sophisticated and formalized way of warfare than previously appreciated in the European Neolithic record.


Assuntos
Violência , Guerra , Adulto , Masculino , Adolescente , Humanos , Europa (Continente) , Espanha , Agressão
3.
Nat Commun ; 14(1): 2930, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37253742

RESUMO

Extinct lineages of Yersinia pestis, the causative agent of the plague, have been identified in several individuals from Eurasia between 5000 and 2500 years before present (BP). One of these, termed the 'LNBA lineage' (Late Neolithic and Bronze Age), has been suggested to have spread into Europe with human groups expanding from the Eurasian steppe. Here, we show that the LNBA plague was spread to Europe's northwestern periphery by sequencing three Yersinia pestis genomes from Britain, all dating to ~4000 cal BP. Two individuals were from an unusual mass burial context in Charterhouse Warren, Somerset, and one individual was from a single burial under a ring cairn monument in Levens, Cumbria. To our knowledge, this represents the earliest evidence of LNBA plague in Britain documented to date. All three British Yersinia pestis genomes belong to a sublineage previously observed in Bronze Age individuals from Central Europe that had lost the putative virulence factor yapC. This sublineage is later found in Eastern Asia ~3200 cal BP. While the severity of the disease is currently unclear, the wide geographic distribution within a few centuries suggests substantial transmissibility.


Assuntos
Peste , Yersinia pestis , Humanos , Peste/epidemiologia , Yersinia pestis/genética , Reino Unido/epidemiologia , Europa (Continente) , Ásia Oriental
4.
Lang Speech ; 66(1): 68-78, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35000476

RESUMO

The relationship between the age of acquisition (AoA) of words and their cerebral hemispheric representation is controversial because the experimental results have been contradictory. However, most of the lexical processing experiments were performed with stimuli consisting of written words. If we want to compare the processing of words learned very early in infancy-when children cannot read-with words learned later, it seems more logical to employ spoken words as experimental stimuli. This study, based on the auditory lexical decision task, used spoken words that were classified according to an objective criterion of AoA with extremely distant means (2.88 vs. 9.28 years old). As revealed by the reaction times, both early and late words were processed more efficiently in the left hemisphere, with no AoA × Hemisphere interaction. The results are discussed from a theoretical point of view, considering that all the experiments were conducted using adult participants.


Assuntos
Aprendizagem , Leitura , Adulto , Criança , Humanos , Fatores Etários , Tempo de Reação
5.
Rapid Commun Mass Spectrom ; 36(21): e9380, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35986908

RESUMO

RATIONALE: The last decade has seen a dramatic increase in the application of serial sampling of human dentine in archaeology. Rapid development in the field has provided many improvements in the methodology, in terms of both time resolution as well as the ability to integrate more isotope systems in the analysis. This study provides a comparison of two common sampling approaches, allowing researchers to select the most suitable approach for addressing specific research questions. METHODS: Two common approaches for sequential sampling of human dentine (micro-punches and micro-slices) are compared in terms of viability and efficacy. Using archaeological deciduous second molars and permanent first molars, this study demonstrates how the two approaches capture aspects of the weaning process in different ways. In addition, different aspects related to the extraction protocols, such as the thickness of the central slide and the solubilisation step, are also evaluated. RESULTS: While both approaches show similar intra-tooth isotopic patterns, the micro-punches approach is preferable for research that requires a very fine temporal resolution, while the micro-slices approach is best for research where δ34 S values are needed, or when the samples are poorly preserved. In addition, the solubilisation step has a large effect on collagen yield, and, to a lesser extent, on isotopic compositions. Therefore, it is important to ensure that only samples that have undergone the same pre-treatment protocol are directly compared. CONCLUSIONS: We present the pros and cons of the two micro-sampling approaches and offer possible mitigation strategies to address some of the most important issues related to each approach.


Assuntos
Dentina , Dente , Colágeno , Dentina/química , Humanos , Dente Molar/química , Isótopos de Nitrogênio/análise , Dente/química
6.
J Commun Disord ; 89: 106058, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33316623

RESUMO

OBJECTIVE: The aim of this paper is to assess whether the use of natural metalinguistic skills can be used to differentiate linguistic-communicative profiles of people with dementia (Alzheimer's disease and frontotemporal dementia in the behavioural and primary progressive aphasia variants) in the earliest stages of the disease. METHOD: A sample of 180 people was selected. Sixty had Alzheimer's disease, 20 had frontotemporal dementia of the behavioural variant, and 40 had frontotemporal dementia of the primary progressive aphasia variant (20 had non-fluent primary progressive aphasia and 20 had semantic dementia). The control group was composed of 60 healthy people with ages, gender, and professions as similar as possible to those of the people in the dementia groups. All the participants were administered the Spanish adaptation of the Mini-Mental State Examination (MMSE) and the Global Deterioration Scale (GDS) to assess dementia severity. To assess the use of natural metalinguistic skills, a 40-item test (MetAphAs), specifically designed for this aim, was administered. RESULTS: The test showed high internal validity and high positive correlations with the MMSE. Statistically significant differences were observed in the total scores on this test and in the scores on each of its sections, when comparing the whole group and the subgroups of people with dementia with the control group. Additionally, the scores on most of the sections of the MetAphAs test presented statistically significant differences when the different subgroups of people with dementia were compared. CONCLUSIONS: A test like the MetAphAs, specifically designed to assess natural metalinguistic abilities, may be useful for obtaining differential communicative-linguistic profiles according to the type of dementia in the early stages of the disease. However, additional research is needed to obtain more conclusive results.


Assuntos
Doença de Alzheimer , Afasia Primária Progressiva , Demência Frontotemporal , Linguística , Humanos , Testes Neuropsicológicos
7.
Am J Phys Anthropol ; 173(4): 776-783, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32779777

RESUMO

OBJECTIVES: Stable isotope analysis of sequential dentine samples is a potentially powerful method to reveal insights into early life-histories of individuals in the past. Dentine incremental growth structures are complex, however, and current approaches that apply horizontal sectioning of demineralized tooth halves or quarters risk combining multiple growth layers and may include unwanted cementum or secondary dentine. They also require destruction of large parts of a tooth. Here, we present a less destructive and relatively straightforward protocol that reduces damage, increases temporal resolution, and improves the accuracy of age-alignment between individuals. MATERIAL AND METHODS: We outline a protocol that includes the sampling of small (1 mm diameter) cylindrical plug transects from a thin section, along with an age-alignment scheme predicated on average growth rates for dentine areas. RESULTS AND DISCUSSION: The proposed protocol is readily applicable and more anatomically sensitive than horizontal slicing. Micro-samples are smaller (in both length and depth), hence minimizing temporal overlap and avoid directions that may contravene growth pattern. They completely avoid areas where secondary and tertiary dentine or cementum can be deposited. Age-alignment is improved by using growth ratios of anatomical tooth zones. CONCLUSION: This method minimizes destruction, enables finer temporal resolution and facilitates data comparison. It can be readily combined with fluorescence imaging-based or other pre-screening methods of dentine collagen preservation.


Assuntos
Determinação da Idade pelos Dentes/métodos , Dentina/química , Dente/química , Adolescente , Adulto , Antropologia Física , Isótopos de Carbono/análise , Criança , Pré-Escolar , Dieta , Humanos , Lactente , Isótopos de Nitrogênio/análise , Dente/crescimento & desenvolvimento , Adulto Jovem
8.
Appl Radiat Isot ; 154: 108894, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31581060

RESUMO

Measuring the radioactive content of environmental samples requires the use of appropriate reference materials with the same composition and density as the matrices to be measured. If they are not available, ad hoc artificially spiked reference materials are an alternative. Spiking in layers requires a detailed study of the drop distribution, as energy and decay scheme of the component radionuclides must be taken into account to produce a reference material that represents, in efficiency terms, a real sample. A method based on Monte Carlo simulation has been developed to find the optimal distribution of drops in layers for the combination of two typical soil samples and four radionuclides. Results have been validated by comparison with samples prepared by two techniques: methanol bath and spiking in layers.

9.
Percept Mot Skills ; 126(6): 1047-1057, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31412741

RESUMO

This study tested the hypothesis that two lexical properties, both phonological neighborhood density (ND) and neighborhood frequency (NF), influence the recognition of target words when preceded by either a semantically congruent or semantically neutral context. Our study is the first to test this hypothesis using a language other than English (i.e., Spanish). We used highly familiar bisyllabic nouns with medium-frequency occurrence as target words, and we expected recognition accuracy to increase as ND and NF decreased in both semanticallly congruent and semantically neutral sentences. We presented 48 undergraduate listeners with a set of 80 words, differing in ND and NF, within these two sentence contexts (i.e., 160 sentences). We then tested the relationships between ND, NF, and variations in semantic sentence context within a linear logistic model and found that words with a low frequency of neighbors were more likely to be correctly recognized in both sentence contexts. Thus, during word recognition, the influence of phonological competition outweighed semantic sentence context even when words were presented in Spanish.


Assuntos
Associação , Fonética , Semântica , Percepção da Fala , Teste do Limiar de Recepção da Fala , Adulto , Atenção , Feminino , Humanos , Idioma , Masculino
10.
Psicothema ; 31(3): 305-310, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31292046

RESUMO

BACKGROUND: Semantic inhibition is often found to be impaired in Alzheimer´s disease (AD). The sentence completion task (Hayling test) was used to investigate whether it would be useful for differentiating mild AD from moderate AD. METHOD: Latency responses and error scores in the automatic and inhibition parts of the test were registered in these two groups of patients and in a group of healthy older participants. The types of errors were also analysed. Group differences were analysed by ANOVA. In addition, relationships with other neuropsychological tests were reported. RESULTS: Participants with moderate AD performed worse than controls in both the automatic and inhibition sections, whereas participants with mild AD exhibited impaired performance in the inhibition part, but not in the automatic part. Differences between the groups with mild and moderate AD appeared only in the error scores in the inhibition part, specifically type 3 errors. Error scores in the inhibition part correlated with performance in verbal fluency and working memory tests. CONCLUSIONS: The Hayling task may be a useful tool for investigating control of inhibition in different stages of AD because different patterns of responses were observed.


Assuntos
Doença de Alzheimer/psicologia , Função Executiva , Semântica , Idoso , Doença de Alzheimer/complicações , Análise de Variância , Demência/psicologia , Feminino , Humanos , Inibição Psicológica , Transtornos da Linguagem/diagnóstico , Masculino , Testes Neuropsicológicos , Índice de Gravidade de Doença
12.
Int J Psychol ; 54(1): 135-143, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28503775

RESUMO

Despite important advances made in recent decades, women are still underrepresented in science (less than 30% of authorships). This study presents a bibliometric analysis of all the Psychology articles published in 2009 included in the Web of Science database (Thomson Reuters) in order to examine the contribution of women in contemporary Psychology, their pattern of research collaboration, the scientific content and the scientific impact from a gender perspective. From a total of 90,067 authorships, gender could be identified in 74,413 (82.6%) of them, being 40,782 (54.8%) male authorships and 33,631 (45.2%) female authorships. These data corresponded to 24,477 (49.9%) individual men and 24,553 (50.1%) women, respectively. Therefore, Psychology presents gender parity in the number of authors, and a gender asymmetry in the number of authorships that it is much lower than in science in general and other specific scientific fields. In relative terms, women tend to be concentrated in the first position of the authorship by-line and much less in the last (senior) position. This double pattern suggests that age probably plays a role in (partly) explaining the slight gender disparity of authorships.


Assuntos
Psicologia/métodos , Feminino , Identidade de Gênero , Humanos , Masculino , Comportamento Social
13.
Psychol Rep ; 122(2): 525-535, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29388505

RESUMO

Sexual attraction in humans is influenced by cultural or moral factors, and some gender differences can emerge in this complex interaction. A previous study found that men dissociate sexual attraction from moral judgment more than women do. Two experiments consisting of giving attractiveness ratings to photos of real opposite-sex individuals showed that men, compared to women, were significantly less influenced by the moral valence of a description about the person shown in each photo. There is evidence of some processing differences between real and artificial computer-generated faces. The present study tests the robustness of González-Álvarez's findings and extends the research to an experimental design using artificial face models as stimuli. A sample of 88 young adults (61 females and 27 males, average age 19.32, SD = 2.38) rated the attractiveness of 80 3D artificial face models generated with the FaceGen Modeller 3.5 software. Each face model was paired with a "good" and a "bad" (from a moral point of view) sentence depicting a quality or activity of the person represented in the model (e.g., she/he is an altruistic nurse in Africa vs. she/he is a prominent drug dealer). Results were in line with the previous findings and showed that, with artificial faces as well, sexual attraction is less influenced by morality in men than in women. This gender difference is consistent with an evolutionary perspective on human sexuality.


Assuntos
Beleza , Reconhecimento Facial/fisiologia , Princípios Morais , Caracteres Sexuais , Comportamento Sexual/fisiologia , Percepção Social , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
14.
JCI Insight ; 3(18)2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30232268

RESUMO

Cardiac Nav1.5 and Kir2.1-2.3 channels generate Na (INa) and inward rectifier K (IK1) currents, respectively. The functional INa and IK1 interplay is reinforced by the positive and reciprocal modulation between Nav15 and Kir2.1/2.2 channels to strengthen the control of ventricular excitability. Loss-of-function mutations in the SCN5A gene, which encodes Nav1.5 channels, underlie several inherited arrhythmogenic syndromes, including Brugada syndrome (BrS). We investigated whether the presence of BrS-associated mutations alters IK1 density concomitantly with INa density. Results obtained using mouse models of SCN5A haploinsufficiency, and the overexpression of native and mutated Nav1.5 channels in expression systems - rat ventricular cardiomyocytes and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) - demonstrated that endoplasmic reticulum (ER) trafficking-defective Nav1.5 channels significantly decreased IK1, since they did not positively modulate Kir2.1/2.2 channels. Moreover, Golgi trafficking-defective Nav1.5 mutants produced a dominant negative effect on Kir2.1/2.2 and thus an additional IK1 reduction. Moreover, ER trafficking-defective Nav1.5 channels can be partially rescued by Kir2.1/2.2 channels through an unconventional secretory route that involves Golgi reassembly stacking proteins (GRASPs). Therefore, cardiac excitability would be greatly affected in subjects harboring Nav1.5 mutations with Golgi trafficking defects, since these mutants can concomitantly trap Kir2.1/2.2 channels, thus unexpectedly decreasing IK1 in addition to INa.


Assuntos
Síndrome de Brugada/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Animais , Arritmias Cardíacas/metabolismo , Células CHO , Cricetulus , Proteínas da Matriz do Complexo de Golgi , Humanos , Células-Tronco Pluripotentes Induzidas , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Miócitos Cardíacos/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canais de Potássio/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Ratos , Ratos Sprague-Dawley , Canais de Sódio/metabolismo
15.
Am J Phys Anthropol ; 166(3): 760-771, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29543322

RESUMO

OBJECTIVES: San Juan ante Portam Latinam is one of a small number of European Neolithic sites meeting many of the archaeological criteria expected for a mass grave, and furthermore presents evidence for violent conflict. This study aims to differentiate between what is potentially a single episode of deposition, versus deposition over some centuries, or, alternatively, that resulting from a combination of catastrophic and attritional mortality. The criteria developed are intended to have wider applicability to other such proposed events. MATERIAL AND METHODS: Ten new AMS 14 C determinations on human bone from the site, together with previously available dates, are analyzed through Bayesian modeling to refine the site's chronology. This is used together with the population's demographic profile as the basis for agent-based demographic modeling. RESULTS: The new radiocarbon results, while improving the site's chronology, fail to resolve the question whether the burial represents a single event, or deposition over decades or centuries-primarily because the dates fall within the late fourth millennium BC plateau in the calibration curve. The demographic modeling indicates that the population's age and sex distribution fits neither a single catastrophic event nor a fully attritional mortality profile, but instead may partake of elements of both. DISCUSSION: It is proposed that San Juan ante Portam Latinam was used as burial place for the mainly adolescent and adult male dead of a particular or multiple violent engagements (e.g., battles), while previously or subsequently seeing use for attritional burial by other members of one or more surrounding communities dead over the course of a few generations. The overall bias towards males, particularly to the extent that many may represent conflict mortality, has implications for the structure of the surviving community, the members of which may have experienced increased vulnerability in the face of neighboring aggressors.


Assuntos
Sepultamento/história , Paleontologia , Datação Radiométrica , Adolescente , Adulto , Arqueologia , Conflitos Armados/história , Teorema de Bayes , Osso e Ossos/química , Criança , Pré-Escolar , Feminino , História Antiga , Humanos , Masculino , Pessoa de Meia-Idade , Espanha , Adulto Jovem
16.
PLoS One ; 12(9): e0177881, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28953890

RESUMO

Variation in burial location and treatment is often observed in the prehistoric archaeological record, but its interpretation is usually highly ambiguous. Biomolecular approaches provide the means of addressing this variability in a way not previously possible, linking the lives of individuals to their funerary treatment. Here, we undertake stable carbon and nitrogen isotope analyses on a substantial sample of 166 individuals from a series of broadly contemporary Late Neolithic/ Early Chalcolithic (3500 to 2900 cal BC) mortuary monuments (El Sotillo, Alto de la Huesera, Chabola de la Hechicera and Longar) and caves (Las Yurdinas II, Los Husos I and Peña Larga) within a very spatially restricted area of north-central Spain, with sites separated by no more than 10 km on average. This spatial and temporal proximity allows us to focus on the question at the appropriate scale of analysis, avoiding confounding variables such as environmental change, diachronic trends in the subsistence economy, etc. The results demonstrate a statistically significant difference in human δ13C values between those interred in caves and those placed in monuments. The difference appears to be correlated with fine-grained environmental factors (elevation/ temperature/ precipitation), suggesting that use of the landscape was being divided at a very local scale. The reasons for this partitioning may involve differential social status (e.g. those interred in caves may be of lower standing with more restricted access to the valley's arable resources) or economic specialization (e.g. upland herding vs. valley farming) within the same community or, alternatively, different populations performing different funerary practices and following distinct subsistence economies in some respect. Our results contribute to a better understanding of the development of social differentiation and community specialisation on the scale of the immediate lived landscape.


Assuntos
Práticas Mortuárias , Feminino , Fósseis , História Antiga , Humanos , Masculino , Espanha
17.
Arch Clin Neuropsychol ; 32(2): 198-214, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28365747

RESUMO

OBJECTIVE: Cognitive aging is commonly associated with a decrease in executive functioning (EF). A specific component of EF, semantic inhibition, is addressed in the present study, which presents a meta-analytic review of the literature that has evaluated the performance on the Hayling Sentence Completion test in young and older groups of individuals in order to assess the magnitude of the age effect. METHOD: A systematic search involving Web of Science, PsyINFO, PsychARTICLE, and MedLine databases and Google Scholar was performed. A total of 11 studies were included in this meta-analysis, encompassing a total of 887 participants; 440 young and 447 older adults. The effect sizes for group differences on four measures of the Hayling test, latency responses and error scores on the Automatic and Inhibition sections of the test were calculated using the Comprehensive Meta-Analysis software package. RESULTS: The results revealed large age effects for response latencies in both the Automatic (Hedges' g = 0.81) and Inhibitory conditions (Hedges' g = 0.98), though the latter two effect sizes did not differ from each other. In contrast, analysis of errors revealed a significant difference between the small effect seen in the Automatic condition (Hedges' g = 0.13) relative to the moderate effect seen in the Inhibition condition (Hedges' g = 0.55). CONCLUSIONS: These results may be important for a better understanding of the inhibitory functioning in elderly individuals, although they should be interpreted with caution because of the limited number of studies in the literature to date.


Assuntos
Envelhecimento , Inibição Psicológica , Testes Neuropsicológicos , Semântica , Bases de Dados Bibliográficas/estatística & dados numéricos , Humanos
18.
Appl Radiat Isot ; 126: 273-278, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28314506

RESUMO

The results of the three years European Metrology Research Programme's (EMRP) joint research project 'Metrology for processing materials with high natural radioactivity' (MetroNORM) are presented. In this project, metrologically sound novel instruments and procedures for laboratory and in-situ NORM activity measurements have been developed. Additionally, standard reference materials and sources for traceable calibration and improved decay data of natural radionuclides have been established.

19.
Appl Radiat Isot ; 126: 307-310, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28222954

RESUMO

This paper discusses the use of CeBr3 detectors for the analysis of NORM samples. These detectors have a number of characteristics that make them suitable to field measurements: they can work at ambient temperatures, have better energy resolution than NaI(Tl) detectors for energies over 100keV and do not present the radioactive contamination typical of the lanthanum halides detectors. Results of the measurements made at the laboratory for three reference materials are compared to those made using a conventional HPGe gamma-ray spectrometer system. Spectra from both measurement systems are presented and discussed.

20.
Appl Radiat Isot ; 126: 289-292, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28108187

RESUMO

NORM emits many different gamma energies that have to be analysed by an expert. Alternatively, artificial neural networks (ANNs) can be used. These mathematical software tools can generalize "knowledge" gained from training datasets, applying it to new problems. No expert knowledge of gamma-ray spectrometry is needed by the end-user. In this work an ANN was created that is able to decide from the raw gamma-ray spectrum if the activity concentrations in a sample are above or below the exemption limits.

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