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1.
Cogn Process ; 24(3): 327-338, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37115463

RESUMO

Deontic norms are expected to impose individuals' control over their behavior. In this paper, we address such norms presented in traffic signs and test their influence over executive control functions. For Experiment 1, we develop a traffic flanker task in which the typical neutral arrows are replaced with traffic prohibition/obligation signs. Experiment 2 isolated the deontic aspect of the signs using simple arrows on red, blue, and green backgrounds and either primed them to be interpreted as traffic signs or as elements of a gaming console controller. Results in both studies show evidence of controlling context interferences more efficiently when dealing with deontic (traffic) signs than with simple arrows (Experiment 1) or with similar perceptive targets when primed with a deontic context than with a gaming context (Experiment 2). In both studies, obligation/blue signs mitigate flanker effects less than prohibition/red signs. Stimuli color affects the alertness of the cognitive system, with the color red being, by itself, a cue for increased control. Based on temporal analysis, we further discuss these results as evidence of an increase in proactive control that aims to prevent the occurrence of undesirable influence.


Assuntos
Atenção , Função Executiva , Humanos
2.
J Child Adolesc Trauma ; 15(3): 627-637, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35958709

RESUMO

The UCLA PTSD Reaction Index for DSM-5 (RI-5) is a developmentally appropriate and well recognized screening tool for the assessment of Post-Traumatic Stress Disorder (PTSD) in children and adolescents. The children/adolescent self-report version of the RI-5 has been thoroughly studied in very recent years, showing adequate psychometric properties. Despite such results, the utility of the parent/caregiver-report version, which also integrates the RI-5 system, remains to be explored. As such, the present study aimed to test the general psychometric properties of the parent/caregiver-report version of RI-5, based on a sample of 457 children and adolescents, aged between 7 and 17 years, exposed to at least one potentially traumatic experience, and their respective primary caregivers. The RI-5 total score and categories revealed good internal consistency reliability. The total number of traumas reported emerged as a significant predictor of the RI-5 total score. The RI-5 total score proved to be significantly correlated with more internalizing and externalizing problems, but correlation coefficients were below .70, serving as an indicator of discriminant validity. The four-factor structure of the RI-5 was supported through confirmatory factor analysis. In conclusion, the present study provided preliminary evidence supporting the utility of the parent/caregiver-report version of the RI-5 for research purposes and for clinical assessment and treatment, anchored on a multiple informant perspective of child psychopathology.

3.
Science ; 374(6572): 1271-1275, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34855492

RESUMO

Ultrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 ± 0.054 Earth-radii and a mass of 0.546 ± 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8.106 ± 2.165 grams per cubic centimeter­close to that of iron. An interior structure model predicts that the planet has an iron core radius fraction of 86 ± 5%, similar to that of Mercury's interior.

4.
Science ; 374(6565): 330-332, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34648350

RESUMO

Stars and planets both form by accreting material from a surrounding disk. Because they grow from the same material, theory predicts that there should be a relationship between their compositions. In this study, we search for a compositional link between rocky exoplanets and their host stars. We estimate the iron-mass fraction of rocky exoplanets from their masses and radii and compare it with the compositions of their host stars, which we assume reflect the compositions of the protoplanetary disks. We find a correlation (but not a 1:1 relationship) between these two quantities, with a slope of >4, which we interpret as being attributable to planet formation processes. Super-Earths and super-Mercuries appear to be distinct populations with differing compositions, implying differences in their formation processes.

5.
Nature ; 583(7814): 39-42, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612222

RESUMO

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune 'desert'1,2 (a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4 and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune's but an anomalously large mass of [Formula: see text] Earth masses and a density of [Formula: see text] grams per cubic centimetre, similar to Earth's. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than [Formula: see text] per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

6.
Nature ; 580(7805): 597-601, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32161364

RESUMO

Ultrahot giant exoplanets receive thousands of times Earth's insolation1,2. Their high-temperature atmospheres (greater than 2,000 kelvin) are ideal laboratories for studying extreme planetary climates and chemistry3-5. Daysides are predicted to be cloud-free, dominated by atomic species6 and much hotter than nightsides5,7,8. Atoms are expected to recombine into molecules over the nightside9, resulting in different day and night chemistries. Although metallic elements and a large temperature contrast have been observed10-14, no chemical gradient has been measured across the surface of such an exoplanet. Different atmospheric chemistry between the day-to-night ('evening') and night-to-day ('morning') terminators could, however, be revealed as an asymmetric absorption signature during transit4,7,15. Here we report the detection of an asymmetric atmospheric signature in the ultrahot exoplanet WASP-76b. We spectrally and temporally resolve this signature using a combination of high-dispersion spectroscopy with a large photon-collecting area. The absorption signal, attributed to neutral iron, is blueshifted by -11 ± 0.7 kilometres per second on the trailing limb, which can be explained by a combination of planetary rotation and wind blowing from the hot dayside16. In contrast, no signal arises from the nightside close to the morning terminator, showing that atomic iron is not absorbing starlight there. We conclude that iron must therefore condense during its journey across the nightside.

7.
Phys Rev Lett ; 123(6): 061101, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31491188

RESUMO

Raman scattering enables unforeseen uses for the laser guide-star system of the Very Large Telescope. Here, we present the observation of one up-link sodium laser beam acquired with the ESPRESSO spectrograph at a resolution λ/Δλ∼140 000. In 900 s on source, we detect the pure rotational Raman lines of ^{16}O_{2}, ^{14}N_{2}, and ^{14}N^{15}N (tentatively) up to rotational quantum numbers J of 27, 24, and 9, respectively. We detect the ^{16}O_{2} fine-structure lines induced by the interaction of the electronic spin S and end-over-end rotational angular momentum N in the electronic ground state of this molecule up to N=9. The same spectrum also reveals the ν_{1←0} rotational-vibrational Q-branch for ^{16}O_{2} and ^{14}N_{2}. These observations demonstrate the potential of using laser guide-star systems as accurate calibration sources for characterizing new astronomical spectrographs.

8.
Braz. oral res. (Online) ; 33: e008, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989480

RESUMO

Abstract The aim of this study was to evaluate the degree of conversion (DC) and the thermal stability of bulk-fill and conventional composite resins. Eleven composite resin samples were prepared to evaluate the DC, Vickers microhardness (VMH), mass and residue/particle loss, glass transition temperature (Tg), enthalpy, and linear coefficient of thermal expansion (CTE) using infrared spectroscopy (FTIR), microdurometer analyses, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dilatometry (DIL). The data were subjected to statistical analysis, with a significance level of 95%. DC and VMH were not influenced by the polymerized side of the sample, and statistical differences were recorded only among the materials. Decomposition temperature, melting, and mass and residue loss were dependent on the material and on the evaluation condition (polymerized and non-polymerized). Tg values were similar between the composites, without statistically significant difference, and CTE ranged from 10.5 to 37.1 (10-6/°C), with no statistical difference between the materials. There was a moderate negative correlation between CTE and the % of load particles, by weight. Most resins had a DC above that which is reported in the literature. TGA, Tg, and CTE analyses showed the thermal behavior of the evaluated composites, providing data for future research, assisting with the choice of material for direct or semidirect restorations, and helping choose the appropriate temperature for increasing the DC of such materials.


Assuntos
Propriedades de Superfície , Teste de Materiais/métodos , Resinas Compostas/química , Materiais Dentários/química , Espectrofotometria Infravermelho , Temperatura , Resinas Compostas/análise , Materiais Dentários/análise , Dureza
9.
Folia Neuropathol ; 55(1): 14-22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28430288

RESUMO

Glioblastoma is the most common primary brain tumor. Despite multimodality therapy with aggressive microsurgical resection and adjuvant chemotherapy and radiotherapy, the median survival is below 15 months. Glioblastomas are heterogeneous tumors with high resistance to most chemotherapeutic drugs. According to reliable evidence, YKL-40, one of the best investigated chitinase-like protein, may facilitate invasion, migration and angiogenesis, and could be also responsible for temozolomide resistance in glioblastoma, thus conferring a dismal prognosis. Previous studies have demonstrated that glioblastoma stem cells give rise to endothelial cells through an YKL-40 influence. Such factor is closely related to the subventricular zone. This review focuses on the most recent theories involving the possible relationship between topographic gliomagenesis related to the subventricular zone and YKL-40..


Assuntos
Neoplasias Encefálicas/patologia , Proteína 1 Semelhante à Quitinase-3/metabolismo , Glioblastoma/patologia , Ventrículos Laterais/patologia , Células-Tronco Neoplásicas/patologia , Animais , Biomarcadores Tumorais/metabolismo , Humanos
10.
Orig Life Evol Biosph ; 46(4): 351-359, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27311962

RESUMO

We used a sample of super-Earth-like planets detected by the Doppler spectroscopy and transit techniques to explore the dependence of orbital parameters of the planets on the metallicity of their host stars. We confirm the previous results (although still based on small samples of planets) that super-Earths orbiting around metal-rich stars are not observed to be as distant from their host stars as we observe their metal-poor counterparts to be. The orbits of these super-Earths with metal-rich hosts usually do not reach into the Habitable Zone (HZ), keeping them very hot and inhabitable. We found that most of the known planets in the HZ are orbiting their GK-type hosts which are metal-poor. The metal-poor nature of planets in the HZ suggests a high Mg abundance relative to Si and high Si abundance relative to Fe. These results lead us to speculate that HZ planets might be more frequent in the ancient Galaxy and had compositions different from that of our Earth.


Assuntos
Meio Ambiente Extraterreno , Planetas , Astros Celestes , Exobiologia
11.
Acta odontol. latinoam ; 28(2): 95-102, 2015. tab
Artigo em Inglês | LILACS | ID: lil-768611

RESUMO

The aim of this study was to investigate the influence of digital radiographic display on caries detection and choice of treatment among undergraduate students. Forty images of extracted human teeth were acquired using a PSP digital system. The proximal surfaces were evaluated for the presence of proximal caries and choice of treatment by 36 undergraduate students,divided into three groups according to the semester they were taking. The images were evaluated in two forms of image display: laptop, and printed on acetate viewed on a lightbox.The accuracy of the different forms of image display on caries detection was evaluated by means of ROC curve analysis andits effect by mixed linear regression. Residue analysis was used to verify the adequacy of the treatment of choice for the chosen diagnosis. There was no significant effect either for the display modalities (p=0.058) or for the different undergraduate student groups (p=0.991). The Az was 0.539 for printed images and0.516 for laptop. The decisions based on treatment of choice were consistent with the scores achieved for caries detection. Accuracy of caries detection using a laptop was comparable to accuracy using printed images. Treatment decision was not affected by image display modality. The semester of the dentistry course that undergraduate students were taking did not significantly increase the accuracy of their proximal caries detection.


Objetivo deste estudo foi investigar a influência do meio de apresentação da imagem radiográfica digital no diagnóstico dacarie e na decisão de tratamento realizado por alunos de graduação. Foram obtidas 40 imagens digitais de dentes humanos extraídos através do sistema digital PSP. As superfícies proximais dos dentes foram avaliadas quanto à presença de cárie proximal por 36 estudantes de odontologia, distribuídos em três grupos de acordo com o nível de formação. As avaliações foram efetuadas em um laptop e em imagens impressas com o auxílio do negatoscópio. A acurácia dos meios de apresentação quanto à detecção de cárie incipiente foi avaliada pela média das áreas sob as curvas ROC e seu efeito por uma análise de regressão linear mista. Para a tomada de decisão terapêutica foi realizada uma análise de resíduos para verificar sua adequação ao diagnóstico. Não houve efeito significativo nem para a modalidade de visualização (p=0.058) e nem para os grupos de alunos (p=0.991). A média das áreas sob as curvas Roc para o filme foi de 0.539 e de 0.516 para negatoscópio. A decisão de tratamento foi condizente com o diagnóstico efetuado. A acurácia do diagnóstico da cárie proximal realizado em tela de laptop é comparável ao realizado em negatoscópio. A tomada de decisão terapêutica não foi afetada pelo meio de apresentação da imagem radiográfica digital. A progressão do aluno no curso não melhora a precisão diagnóstica da cárie proximal.


Assuntos
Humanos , Cárie Dentária/diagnóstico , Cárie Dentária , Cárie Dentária/terapia , Radiografia Dentária Digital/métodos , Brasil , Tomada de Decisões , Dentina/ultraestrutura , Esmalte Dentário/ultraestrutura , Técnicas Histológicas , Curva ROC , Interpretação Estatística de Dados , Estudantes de Odontologia
12.
Nature ; 503(7476): 377-80, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24172902

RESUMO

Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.

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