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1.
Neurosci Biobehav Rev ; 163: 105745, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825260

RESUMO

Studying infants in the past is crucial for understanding the evolution of human life history and the evolution of cooperation, cognition, and communication. An infant's growth, health, and mortality can provide information about the dynamics and structure of a population, their cultural practices, and the adaptive capacity of a community. Skeletal remains provide one way of accessing this information for humans recovered prior to the historical periods. Teeth in particular, are retrospective archives of information that can be accessed through morphological, micromorphological, and biogeochemical methods. This review discusses how the microanatomy and formation of teeth, and particularly enamel, serve as archives of somatic growth, stress, and the environment. Examining their role in the broader context of human evolution, we discuss dental biogeochemistry and emphasize how the incremental growth of tooth microstructure facilitates the reconstruction of temporal data related to health, diet, mobility, and stress in past societies. The review concludes by considering tooth microstructure as a biomarker and the potential clinical applications.

2.
Rapid Commun Mass Spectrom ; 38(5): e9692, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355885

RESUMO

RATIONALE: Potassium (K) is a major component of several silicate minerals and seawater, and, therefore, constraining past changes in the potassium cycle is a promising way of tracing large-scale geological processes on Earth. However, [K] measurement using inductively coupled plasma mass spectrometry (ICP-MS) is challenging due to an ArH+ interference, which may be of a similar magnitude to the K+ ion beam in samples with <0.1% m/m [K]. METHODS: In this work, we investigated the effect of the ArH+ interference on K/Ca data quality by comparing results from laser-ablation (LA)-ICP-MS measured in medium and high mass resolution modes and validating our LA results via solution ICP-optical emission spectroscopy (OES) and solution ICP-MS measurements. To do so, we used a wide range of geological reference materials, with a particular focus on marine carbonates, which are potential archives of past changes in the K cycle but are typically characterised by [K] < 200 µg/g. In addition, we examine the degree to which trace-element data quality is driven by downhole fractionation during LA-ICP-MS measurements. RESULTS: Our results show that medium mass resolution (MR) mode is sufficiently capable of minimising the effect of the ArH+ interference on K+ . However, the rate of downhole fractionation for Na and K varies between different samples as a result of their differing bulk composition, resulting in matrix-specific inaccuracy. We show how this can be accounted for via downhole fractionation corrections, resulting in an accuracy of better than 1% and a long-term reproducibility (intermediate precision) of <6% (relative standard deviation) in JCp-1NP using LA-ICP-MS in MR mode. CONCLUSION: Our [K] measurement protocol is demonstrably precise and accurate and applicable to a wide range of materials. The measurement of K/Ca in relatively low-[K] marine carbonates is presented here as a key example of a new application opened up by these advances.

3.
Ultrasound Med Biol ; 49(12): 2527-2536, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37758529

RESUMO

OBJECTIVE: Focused ultrasound (FUS) can modulate neuronal activity by depolarization or hyperpolarization. Although FUS-evoked depolarization has been studied extensively, the mechanisms underlying FUS-evoked hyperpolarization (FUSH) have received little attention. In the study described here, we developed a procedure using FUS to selectively hyperpolarize motor axons in crayfish. As a previous study had reported that these axons express mechano- and thermosensitive two-pore domain potassium (K2P) channels, we tested the hypothesis that K2P channels underlie FUSH. METHODS: Intracellular recordings from a motor axon and a muscle fiber were obtained simultaneously from the crayfish opener neuromuscular preparation. FUSH was examined while K2P channel activities were modulated by varying temperature or by K2P channel blockers. RESULTS: FUSH in the axons did not exhibit a coherent temperature dependence, consistent with predicted K2P channel behavior, although changes in the resting membrane potential of the same axons indicated well-behaved K2P channel temperature dependence. The same conclusion was supported by pharmacological data; namely, FUSH was not suppressed by K2P channel blockers. Comparison between the FUS-evoked responses recorded in motor axons and muscle fibers revealed that the latter exhibited very little FUSH, indicating that the FUSH was specific to the axons. CONCLUSION: It is not likely that K2P channels are the underlying mechanism for FUSH in motor axons. Alternative mechanisms such as sonophore and axon-specific potassium channels were considered. Although the sonophore hypothesis could account for electrophysiological features of axonal recordings, it is not consistent with the lack of FUSH in muscle fibers. An axon-specific and mechanosensitive potassium channel is also a possible explanation.


Assuntos
Astacoidea , Axônios , Animais , Junção Neuromuscular/fisiologia , Neurônios , Canais de Potássio/fisiologia , Fibras Musculares Esqueléticas
4.
Database (Oxford) ; 20232023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37002681

RESUMO

SABIO-RK is a database for biochemical reactions and their kinetics. Data in SABIO-RK are inherently multidimensional and complex. The complex relationships between the data are often difficult to follow or even not represented when using standard tabular views. With an increasing number of data points the mismatch between tables and insights becomes more obvious, and getting an overview of the data becomes harder. Such complex data benefit from being presented using specially adapted visual tools. Visualization is a natural and user-friendly way to quickly get an overview of the data and to detect clusters and outliers. Here, we describe the implementation of a variety of visualization concepts into a common interface within the SABIO-RK biochemical reaction kinetics database. For that purpose, we use a heat map, parallel coordinates and scatter plots to allow the interactive visual exploration of general entry-based information of biochemical reactions and specific kinetic parameter values. Database URL https://sabiork.h-its.org/.


Assuntos
Bases de Dados Factuais , Cinética
5.
Proc Natl Acad Sci U S A ; 120(15): e2213987120, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37011196

RESUMO

The dinosaur-bird transition involved several anatomical, biomechanical, and physiological modifications of the theropod bauplan. Non-avian maniraptoran theropods, such as Troodon, are key to better understand changes in thermophysiology and reproduction occurring during this transition. Here, we applied dual clumped isotope (Δ47 and Δ48) thermometry, a technique that resolves mineralization temperature and other nonthermal information recorded in carbonates, to eggshells from Troodon, modern reptiles, and modern birds. Troodon eggshells show variable temperatures, namely 42 and 29 ± 2 °C, supporting the hypothesis of an endothermic thermophysiology with a heterothermic strategy for this extinct taxon. Dual clumped isotope data also reveal physiological differences in the reproductive systems between Troodon, reptiles, and birds. Troodon and modern reptiles mineralize their eggshells indistinguishable from dual clumped isotope equilibrium, while birds precipitate eggshells characterized by a positive disequilibrium offset in Δ48. Analyses of inorganic calcites suggest that the observed disequilibrium pattern in birds is linked to an amorphous calcium carbonate (ACC) precursor, a carbonate phase known to accelerate eggshell formation in birds. Lack of disequilibrium patterns in reptile and Troodon eggshells implies these vertebrates had not acquired the fast, ACC-based eggshell calcification process characteristic of birds. Observation that Troodon retained a slow reptile-like calcification suggests that it possessed two functional ovaries and was limited in the number of eggs it could produce; thus its large clutches would have been laid by several females. Dual clumped isotope analysis of eggshells of extinct vertebrates sheds light on physiological information otherwise inaccessible in the fossil record.


Assuntos
Casca de Ovo , Répteis , Animais , Feminino , Carbonato de Cálcio , Isótopos
6.
Sci Rep ; 13(1): 3632, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869081

RESUMO

The Early Iron Age in Italy (end of the tenth to the eighth century BCE) was characterized by profound changes which influenced the subsequent political and cultural scenario in the peninsula. At the end of this period people from the eastern Mediterranean (e.g. Phoenicians and Greek people) settled along the Italian, Sardinian and Sicilian coasts. Among local populations, the so-called Villanovan culture group-mainly located on the Tyrrhenian side of central Italy and in the southern Po plain-stood out since the beginning for the extent of their geographical expansion across the peninsula and their leading position in the interaction with diverse groups. The community of Fermo (ninth-fifth century BCE), related to the Villanovan groups but located in the Picene area (Marche), is a model example of these population dynamics. This study integrates archaeological, osteological, carbon (δ13C), nitrogen (δ15N) (n = 25 human) and strontium (87Sr/86Sr) isotope data (n = 54 human, n = 11 baseline samples) to explore human mobility through Fermo funerary contexts. The combination of these different sources enabled us to confirm the presence of non-local individuals and gain insight into community connectivity dynamics in Early Iron Age Italian frontier sites. This research contributes to one of the leading historical questions of Italian development in the first millennium BCE.


Assuntos
Arqueologia , Carbono , Humanos , Geografia , Itália , Nitrogênio
7.
Nat Ecol Evol ; 7(2): 279-289, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646949

RESUMO

During the Early to Middle Pleistocene, Java was inhabited by hominid taxa of great diversity. However, their seasonal dietary strategies have never been explored. We undertook geochemical analyses of orangutan (Pongo sp.), Homo erectus and other mammalian Pleistocene teeth from Sangiran. We reconstructed past dietary strategies at subweekly resolution and inferred seasonal ecological patterns. Histologically controlled spatially resolved elemental analyses by laser-based plasma mass spectrometry confirmed the preservation of authentic biogenic signals despite the effect of spatially restricted diagenetic overprint. The Sr/Ca record of faunal remains is in line with expected trophic positions, contextualizing fossil hominid diet. Pongo sp. displays marked seasonal cycles with ~3 month-long strongly elevated Sr/Ca peaks, reflecting contrasting plant food consumption presumably during the monsoon season, while lower Sr/Ca ratios suggest different food availability during the dry season. In contrast, omnivorous H. erectus shows low and less accentuated intra-annual Sr/Ca variability compared to Pongo sp., with δ13C data of one individual indicating a dietary shift from C4 to a mix of C3 and C4 plants. Our data suggest that H. erectus on Java was maximizing the resources available in more open mosaic habitats and was less dependent on variations in seasonal resource availability. While still influenced by seasonal food availability, we infer that H. erectus was affected to a lesser degree than Pongo sp., which inhabited monsoonal rain forests on Java. We suggest that H. erectus maintained a greater degree of nutritional independence by exploiting the regional diversity of food resources across the seasons.


Assuntos
Hominidae , Dente , Animais , Pongo , Indonésia , Dieta , Mamíferos
8.
Ultrasound Med Biol ; 48(10): 2040-2051, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35882572

RESUMO

We have previously identified a novel non-selective membrane conductance (gUS) opened by focused ultrasound (FUS) in crayfish motor axons. In the work described here, we studied gUS properties further by comparing FUS-evoked depolarization (FUSD) in control and hypotonic saline with 75% of control osmolarity. The FUS was a train of 20 FUS bursts (2.1 MHz and 50 µs per burst) delivered at 1 kHz. The amplitude, onset latency, frequency of occurrence and duration of FUSD were compared in a 15-min time window before and after switching to hypotonic saline. Significant increases were observed for amplitude (p < 0.001) and frequency of occurrence (p < 0.01) while the onset latency exhibited a significant decrease (p < 0.001). FUSD duration did not significantly differ. These results support predictions based on our hypothesis that gUS is mediated by opening of nanopores in the lipid bilayer and that stretching of axonal membrane caused by swelling at low osmolarity should increase the probability of nanopore formation under FUS. The FUSD parameters, in addition, exhibited time-dependent trends when the window of observation was expanded to 45 min in each saline. The statistical significance of amplitude and duration differed between 15- and 45-min time windows, indicating the presence of adaptive responses of axonal membrane to osmotic manipulation.


Assuntos
Astacoidea , Axônios , Animais , Concentração Osmolar , Ultrassonografia
9.
Sci Rep ; 12(1): 8104, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577834

RESUMO

We present the results of a multi-disciplinary investigation on a deciduous human tooth (Pradis 1), recently recovered from the Epigravettian layers of the Grotte di Pradis archaeological site (Northeastern Italian Prealps). Pradis 1 is an exfoliated deciduous molar (Rdm2), lost during life by an 11-12-year-old child. A direct radiocarbon date provided an age of 13,088-12,897 cal BP (95% probability, IntCal20). Amelogenin peptides extracted from tooth enamel and analysed through LC-MS/MS indicate that Pradis 1 likely belonged to a male. Time-resolved 87Sr/86Sr analyses by laser ablation mass spectrometry (LA-MC-ICPMS), combined with dental histology, were able to resolve his movements during the first year of life (i.e. the enamel mineralization interval). Specifically, the Sr isotope ratio of the tooth enamel differs from the local baseline value, suggesting that the child likely spent his first year of life far from Grotte di Pradis. Sr isotopes are also suggestive of a cyclical/seasonal mobility pattern exploited by the Epigravettian human group. The exploitation of Grotte di Pradis on a seasonal, i.e. summer, basis is also indicated by the faunal spectra. Indeed, the nearly 100% occurrence of marmot remains in the entire archaeozoological collection indicates the use of Pradis as a specialized marmot hunting or butchering site. This work represents the first direct assessment of sub-annual movements observed in an Epigravettian hunter-gatherer group from Northern Italy.


Assuntos
Arqueologia , Espectrometria de Massas em Tandem , Arqueologia/métodos , Criança , Cromatografia Líquida , Humanos , Isótopos , Itália , Masculino
10.
Party Politics ; 28(3): 528-540, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35493065

RESUMO

This paper examines the validity of three approaches to estimate party positions on the general left-right and EU dimensions. We newly introduce party elite data from the comprehensive IntUne survey and cross-validate it with existing expert survey and manifesto data. The general left-right estimates generated by elites and experts show a higher congruence than those derived from party manifestos; neither measure clearly materializes as more valid regarding EU positions. We identify which factors explain diverging estimates. For instance, disagreement among experts has greater impact than their mere number. The substantial centrist bias of the manifesto estimates persists even when alternative documents are used to substitute manifestos. Low response rates among elites have no systematic detrimental effect on the validity of party position estimates.

11.
JMIR Med Inform ; 10(4): e29813, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35412464

RESUMO

BACKGROUND: Although decision-makers in health care settings need to read and understand the validity of quantitative reports, they do not always carefully read information on research methods. Presenting the methods in a more structured way could improve the time spent reading the methods and increase the perceived relevance of this important report section. OBJECTIVE: To test the effect of a structured summary of the methods used in a quantitative data report on reading behavior with eye-tracking and measure the effect on the perceived importance of this section. METHODS: A nonrandomized pilot trial was performed in a computer laboratory setting with advanced medical students. All participants were asked to read a quantitative data report; an intervention arm was also shown a textbox summarizing key features of the methods used in the report. Three data-collection methods were used to document reading behavior and the views of participants: eye-tracking (during reading), a written questionnaire, and a face-to-face interview. RESULTS: We included 35 participants, 22 in the control arm and 13 in the intervention arm. The overall time spent reading the methods did not differ between the 2 arms. The intervention arm considered the information in the methods section to be less helpful for decision-making than did the control arm (scores for perceived helpfulness were 4.1 and 2.9, respectively, range 1-10). Participants who read the box more intensively tended to spend more time on the methods as a whole (Pearson correlation 0.81, P=.001). CONCLUSIONS: Adding a structured summary of information on research methods attracted attention from most participants, but did not increase the time spent on reading the methods or lead to increased perceptions that the methods section was helpful for decision-making. Participants made use of the summary to quickly judge the methods, but this did not increase the perceived relevance of this section.

12.
Comp Polit Stud ; 55(2): 254-286, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35103025

RESUMO

One of the most important decisions coalition partners make when forming a government is the division of ministries. Ministerial portfolios provide the party in charge with considerable informational and agenda-setting advantages, which parties can use to shape policies according to their preferences. Oversight mechanisms in parliaments play a central role in mitigating ministerial policy discretion, allowing coalition partners to control each other even though power has been delegated to individual ministers. However, we know relatively little about how such mechanisms influence the agenda-setting and gatekeeping powers of ministers and how much influence minister parties have on policy output relative to the government as a whole in different institutional settings. We fill this gap by analyzing original data on over 2000 important social and economic policy reform measures adopted in nine Western European countries over 20 years, based on a coding of more than 1200 country reports issued by the Economist Intelligence Unit and the Organisation for Economic Co-operation and Development (OECD). We find that parliaments with strong oversight powers constrain the agenda-setting capacity of minister parties but have limited impact on their gatekeeping capacity. Our findings have important implications for our understanding of policy-making and democratic accountability.

13.
F1000Res ; 112022.
Artigo em Inglês | MEDLINE | ID: mdl-36742342

RESUMO

In this white paper, we describe the founding of a new ELIXIR Community - the Systems Biology Community - and its proposed future contributions to both ELIXIR and the broader community of systems biologists in Europe and worldwide. The Community believes that the infrastructure aspects of systems biology - databases, (modelling) tools and standards development, as well as training and access to cloud infrastructure - are not only appropriate components of the ELIXIR infrastructure, but will prove key components of ELIXIR's future support of advanced biological applications and personalised medicine. By way of a series of meetings, the Community identified seven key areas for its future activities, reflecting both future needs and previous and current activities within ELIXIR Platforms and Communities. These are: overcoming barriers to the wider uptake of systems biology; linking new and existing data to systems biology models; interoperability of systems biology resources; further development and embedding of systems medicine; provisioning of modelling as a service; building and coordinating capacity building and training resources; and supporting industrial embedding of systems biology. A set of objectives for the Community has been identified under four main headline areas: Standardisation and Interoperability, Technology, Capacity Building and Training, and Industrial Embedding. These are grouped into short-term (3-year), mid-term (6-year) and long-term (10-year) objectives.


Assuntos
Biologia de Sistemas , Europa (Continente) , Bases de Dados Factuais
14.
Geophys Res Lett ; 48(8): e2020GL091883, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-34149115

RESUMO

Many nations responded to the corona virus disease-2019 (COVID-19) pandemic by restricting travel and other activities during 2020, resulting in temporarily reduced emissions of CO2, other greenhouse gases and ozone and aerosol precursors. We present the initial results from a coordinated Intercomparison, CovidMIP, of Earth system model simulations which assess the impact on climate of these emissions reductions. 12 models performed multiple initial-condition ensembles to produce over 300 simulations spanning both initial condition and model structural uncertainty. We find model consensus on reduced aerosol amounts (particularly over southern and eastern Asia) and associated increases in surface shortwave radiation levels. However, any impact on near-surface temperature or rainfall during 2020-2024 is extremely small and is not detectable in this initial analysis. Regional analyses on a finer scale, and closer attention to extremes (especially linked to changes in atmospheric composition and air quality) are required to test the impact of COVID-19-related emission reductions on near-term climate.

15.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33589928

RESUMO

This article describes some use case studies and self-assessments of FAIR status of de.NBI services to illustrate the challenges and requirements for the definition of the needs of adhering to the FAIR (findable, accessible, interoperable and reusable) data principles in a large distributed bioinformatics infrastructure. We address the challenge of heterogeneity of wet lab technologies, data, metadata, software, computational workflows and the levels of implementation and monitoring of FAIR principles within the different bioinformatics sub-disciplines joint in de.NBI. On the one hand, this broad service landscape and the excellent network of experts are a strong basis for the development of useful research data management plans. On the other hand, the large number of tools and techniques maintained by distributed teams renders FAIR compliance challenging.


Assuntos
Gerenciamento de Dados/métodos , Metadados , Redes Neurais de Computação , Proteômica/métodos , Software , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cooperação Internacional , Fenótipo , Plantas/genética , Proteoma , Autoavaliação (Psicologia) , Fluxo de Trabalho
16.
BMC Med Inform Decis Mak ; 21(1): 32, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509172

RESUMO

BACKGROUND: Quantitative data reports are widely produced to inform health policy decisions. Policymakers are expected to critically assess provided information in order to incorporate the best available evidence into the decision-making process. Many other factors are known to influence this process, but little is known about how quantitative data reports are actually read. We explored the reading behavior of (future) health policy decision-makers, using innovative methods. METHODS: We conducted a computer-assisted laboratory study, involving starting and advanced students in medicine and health sciences, and professionals as participants. They read a quantitative data report to inform a decision on the use of resources for long-term care in dementia in a hypothetical decision scenario. Data were collected through eye-tracking, questionnaires, and a brief interview. Eye-tracking data were used to generate 'heatmaps' and five measures of reading behavior. The questionnaires provided participants' perceptions of understandability and helpfulness as well as individual characteristics. Interviews documented reasons for attention to specific report sections. The quantitative analysis was largely descriptive, complemented by Pearson correlations. Interviews were analyzed by qualitative content analysis. RESULTS: In total, 46 individuals participated [students (85%), professionals (15%)]. Eye-tracking observations showed that the participants spent equal time and attention for most parts of the presented report, but were less focused when reading the methods section. The qualitative content analysis identified 29 reasons for attention to a report section related to four topics. Eye-tracking measures were largely unrelated to participants' perceptions of understandability and helpfulness of the report. CONCLUSIONS: Eye-tracking data added information on reading behaviors that were not captured by questionnaires or interviews with health decision-makers.


Assuntos
Laboratórios , Formulação de Políticas , Computadores , Política de Saúde , Humanos , Projetos de Pesquisa
17.
PLoS Comput Biol ; 17(1): e1008646, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33497393

RESUMO

Reproducibility and reusability of the results of data-based modeling studies are essential. Yet, there has been-so far-no broadly supported format for the specification of parameter estimation problems in systems biology. Here, we introduce PEtab, a format which facilitates the specification of parameter estimation problems using Systems Biology Markup Language (SBML) models and a set of tab-separated value files describing the observation model and experimental data as well as parameters to be estimated. We already implemented PEtab support into eight well-established model simulation and parameter estimation toolboxes with hundreds of users in total. We provide a Python library for validation and modification of a PEtab problem and currently 20 example parameter estimation problems based on recent studies.


Assuntos
Linguagens de Programação , Biologia de Sistemas/métodos , Algoritmos , Bases de Dados Factuais , Modelos Biológicos , Modelos Estatísticos , Reprodutibilidade dos Testes
18.
Rofo ; 193(7): 778-786, 2021 Jul.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-33327031

RESUMO

BACKGROUND: The exposure of a pregnant woman to X-rays is an event that can cause uncertainty for all concerned. This review provides guidance on how to assess such a situation and how to determine the dose to the unborn child. In general, the use of X-rays in pregnant women in radiology should be avoided. If possible, alternatives should be used, or examinations postponed to a time after the pregnancy. This review gives a summary of the procedure for determining the radiation exposure of a pregnant woman. METHOD: Based on the previous report of 2002 and the literature on prenatal radiation exposure published thereafter, the DGMP/DRG report on the procedure for the assessment of prenatal radiation exposure was adapted to the current state of science and technology. RESULTS: Typically, only relatively low radiation exposures of less than 20 mSv occur for the unborn child in X-ray diagnostics in the vast majority of cases. At these dose level the additional risk of damage to the embryo or fetus caused by the radiation is low and therefore only a rough conservative estimate using tabulated values are made. Only in a few types of examination (CT and interventional radiology) higher doses values might occur in the uterus. Instead of dose estimates (step 1 in the two-step model) in these cases the calculation of dose (step 2) are required and further action by the physician may be necessary. CONCLUSIONS: During the assessment, it is useful to initially use simple conservative estimation procedures to quickly determine whether a case falls into this large group less than 20 mSv, where there is a very low risk to the unborn child. If this is the case, the pregnant woman should be informed immediately by the doctor who performed the examination/treatment. This avoids a psychological burden on the patient. The DGMP/DRG report suggests a relatively simple, clearly structured procedure with advantages for all parties involved (physician, medical physics experts, MTRA and patient). KEY POINTS: · The DGMP/DRG report on prenatal radiation exposure describes the procedure for calculating radiation exposures and the associated risks for the unborn child.. · Using the two-step model, only a simple assessment based on the first step is necessary for most prenatal radiation exposures.. · With the given tables it is possible to estimate individual risks for the unborn child taking into account the radiation exposure.. · Only in the rare case that the first estimate results in a uterine dose larger 20 mSv a more accurate calculation is necessary.. CITATION FORMAT: · Fiebich M, Block A, Borowski M et al. Prenatal radiation exposure in diagnostic and interventional radiology. Fortschr Röntgenstr 2021; 193: 778 - 786.


Assuntos
Feto/efeitos da radiação , Doses de Radiação , Exposição à Radiação/efeitos adversos , Radiologia Intervencionista , Relação Dose-Resposta à Radiação , Feminino , Humanos , Gravidez , Exposição à Radiação/análise
19.
Proc Natl Acad Sci U S A ; 117(46): 28719-28726, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33139541

RESUMO

The early onset of weaning in modern humans has been linked to the high nutritional demand of brain development that is intimately connected with infant physiology and growth rate. In Neanderthals, ontogenetic patterns in early life are still debated, with some studies suggesting an accelerated development and others indicating only subtle differences vs. modern humans. Here we report the onset of weaning and rates of enamel growth using an unprecedented sample set of three late (∼70 to 50 ka) Neanderthals and one Upper Paleolithic modern human from northeastern Italy via spatially resolved chemical/isotopic analyses and histomorphometry of deciduous teeth. Our results reveal that the modern human nursing strategy, with onset of weaning at 5 to 6 mo, was present among these Neanderthals. This evidence, combined with dental development akin to modern humans, highlights their similar metabolic constraints during early life and excludes late weaning as a factor contributing to Neanderthals' demise.


Assuntos
Esmalte Dentário/crescimento & desenvolvimento , Homem de Neandertal/crescimento & desenvolvimento , Desmame , Animais , Esmalte Dentário/química , Humanos , Lactente , Recém-Nascido
20.
Sci Rep ; 10(1): 10386, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32587350

RESUMO

Mobility of people and goods during the Upper Paleolithic has proven difficult to reconstruct given the relative rareness of remains. Nevertheless, archaeological contexts like the Late Pleistocene horizon of Borsuka Cave (Southern Poland) represent a unique opportunity to explore patterns of objects' transportation across Central Europe. We investigated the origin of four ornaments made of European elk (Alces alces L.) incisors recovered at Borsuka Cave - the oldest known burial site in Poland, possibly a child grave. Laser-ablation plasma source mass spectrometric analyses of trace elements and Sr isotopic compositions revealed that one elk was roaming within a geologically uniform area while the others changed their pastures during their lifetimes. The non-local origin of the elk teeth is inferred from their exotic Sr isotopic compositions and the lack of evidence for the presence of elk in this territory during the Pleistocene. Instead, the elks' Sr isotopic composition show good agreement with sites near the Austria-Slovakia border region and northern Hungary, ~250 km away from the study site. We argue that the artefacts were most likely brought to Borsuka Cave by humans or by a network of exchange, so far never reported in the time range 32.5-28.8 ka cal BP for Southern Poland.


Assuntos
Esmalte Dentário/anatomia & histologia , Hominidae/anatomia & histologia , Migração Humana , Paleontologia , Estações do Ano , Isótopos de Estrôncio/análise , Dente/anatomia & histologia , Animais , Europa (Continente) , Humanos
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