This study examines the effect of foreign-accented speech on the predictive ability of our brain. Listeners actively anticipate upcoming linguistic information in the speech signal so as to ...facilitate and reduce processing load. However, it is unclear whether or not listeners also do this when they are exposed to speech from non-native speakers. In the present study, we exposed native Dutch listeners to sentences produced by native and non-native speakers while measuring their brain activity using electroencephalography. We found that listeners’ brain activity differed depending on whether they listened to native or non-native speech. However, participants’ overall performance as measured by word recall rate was unaffected. We discussed the results in relation to previous findings as well as the automaticity of anticipation.
Aims.We present a new continuum 3D radiative transfer code, MCFOST, based on a Monte-Carlo method. MCFOST can be used to calculate (i) monochromatic images in scattered light and/or thermal emission; ...(ii) polarisation maps; (iii) interferometric visibilities; (iv) spectral energy distributions; and (v) dust temperature distributions of protoplanetary disks. Methods.Several improvements to the standard Monte Carlo method are implemented in MCFOST to increase efficiency and reduce convergence time, including wavelength distribution adjustments, mean intensity calculations, and an adaptive sampling of the radiation field. The reliability and efficiency of the code are tested against a previously-defined benchmark, using a 2D disk configuration. No significant difference (no more than 10% and usually much less) is found between the temperatures and SEDs calculated by MCFOST and by other codes included in the benchmark. Results. A study of the lowest disk mass detectable by Spitzer, around young stars, is presented and the colours of “representative” parametric disks compared to recent IRAC and MIPS Spitzer colours of solar-like young stars located in nearby star-forming regions.
GRAIN ALIGNMENT IN STARLESS CORES Jones, T. J.; Bagley, M.; Krejny, M. ...
The Astronomical journal,
01/2015, Letnik:
149, Številka:
1
Journal Article
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ABSTRACT We present near-IR polarimetry data of background stars shining through a selection of starless cores taken in the K band, probing visual extinctions up to . We find that continues to ...decline with increasing AV with a power law slope of roughly −0.5. Examination of published submillimeter (submm) polarimetry of starless cores suggests that by the slope for P versus τ becomes ∼−1, indicating no grain alignment at greater optical depths. Combining these two data sets, we find good evidence that, in the absence of a central illuminating source, the dust grains in dense molecular cloud cores with no internal radiation source cease to become aligned with the local magnetic field at optical depths greater than . A simple model relating the alignment efficiency to the optical depth into the cloud reproduces the observations well.
We present observations of the Cepheus Flare obtained as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Legacy Survey (GBLS) with the SCUBA-2 instrument. We produce a catalogue of ...sources found by SCUBA-2, and separate these into starless cores and protostars. We determine masses and densities for each of our sources, using source temperatures determined by the Herschel Gould Belt Survey. We compare the properties of starless cores in four different molecular clouds: L1147/58, L1172/74, L1251 and L1228. We find that the core mass functions for each region typically show shallower-than-Salpeter behaviour. We find that L1147/58 and L1228 have a high ratio of starless cores to Class II protostars, while L1251 and L1174 have a low ratio, consistent with the latter regions being more active sites of current star formation, while the former are forming stars less actively. We determine that if modelled as thermally supported Bonnor-Ebert spheres, most of our cores have stable configurations accessible to them. We estimate the external pressures on our cores using archival 13CO velocity dispersion measurements and find that our cores are typically pressure confined, rather than gravitationally bound. We perform a virial analysis on our cores, and find that they typically cannot be supported against collapse by internal thermal energy alone, due primarily to the measured external pressures. This suggests that the dominant mode of internal support in starless cores in the Cepheus Flare is either non-thermal motions or internal magnetic fields.
Ternary metal oxides are materials of interest for many applications, from batteries to catalysis. Their crystalline structure and composition determine their properties, and thus it is important to ...achieve control over these features. Here, we demonstrate that solid-state chemistry among nanocrystalline precursors is a promising approach for their synthesis. We show that the crystalline phase of nanocrystal precursors direct that of the ternary reaction product. The combination of X-ray and electron microscopy techniques reveals that the spinel and rhombohedral phases of copper iron oxide are obtained by reacting copper nanocrystals with spinel γ-Fe2O3 and corundum α-Fe2O3 nanocrystals, respectively. Considering the available library of nanocrystals with tunable crystal phases, this discovery opens up an alternative pathway toward the synthesis of a wide variety of ternary and quaternary materials, including those with metastable phases.
We present 450 and 850 m submillimeter continuum observations of the IC 5146 star-forming region taken as part of the James Clerk Maxwell Telescope Gould Belt Survey. We investigate the location of ...bright submillimeter (clumped) emission with the larger-scale molecular cloud through comparison with extinction maps, and find that these denser structures correlate with higher cloud column density. Ninety-six individual submillimeter clumps are identified using FellWalker, and their physical properties are examined. These clumps are found to be relatively massive, ranging from 0.5 to 116 with a mean mass of 8 and a median mass of 3.7 . A stability analysis for the clumps suggests that the majority are (thermally) Jeans stable, with . We further compare the locations of known protostars with the observed submillimeter emission, finding that younger protostars, i.e., Class 0 and I sources, are strongly correlated with submillimeter peaks and that the clumps with protostars are among the most Jeans unstable. Finally, we contrast the evolutionary conditions in the two major star-forming regions within IC 5146: the young cluster associated with the Cocoon Nebula and the more distributed star formation associated with the Northern Streamer filaments. The Cocoon Nebula appears to have converted a higher fraction of its mass into dense clumps and protostars, the clumps are more likely to be Jeans unstable, and a larger fraction of these remaining clumps contain embedded protostars. The Northern Streamer, however, has a larger number of clumps in total and a larger fraction of the known protostars are still embedded within these clumps.
Although limited data are available, it is commonly considered that Europeans and Asians have different skin ageing features.
The present studies have been carried out to evaluate the influence of ...age and sun-exposure on the main clinical signs of Asian skin ageing.
One hundred and sixty Chinese and 160 French age-matched women (age range: 20-60 years old) were clinically examined and scored by the same dermatologist. Facial wrinkles (crow's-feet, glabella and perioral wrinkles) and pigmented spots (on face and hands) were assessed in situ and standardized photographs of the face were taken. Lifelong sun-exposure was estimated from answers to a questionnaire. Comparisons were made between 10-year age groups.
Results show that, for each facial skin area, wrinkle onset is delayed by about 10 years in Chinese women as compared to French women. Facial wrinkling rate over the years is linear in French women and not linear in Chinese women who appear to experience a fast ageing process between age 40 and 50. Pigmented spot intensity is a much more important ageing sign in Chinese women (severe for 30% of women over 40) than in French women (severe for less than 8% of women, irrespective of age).
These first results underline that main skin ageing features (wrinkles, spots) progress differently in the Chinese and French women we have studied. They require to be confirmed on broad multicentre studies involving larger cohorts.
Thermal emission from cold dust grains in giant molecular clouds can be used to probe the physical properties, such as density, temperature and emissivity in star-forming regions. We present the ...Submillimetre Common-User Bolometer Array (SCUBA-2) shared-risk observations at 450 and 850 μm of the Orion A molecular cloud complex taken at the James Clerk Maxwell Telescope (JCMT). Previous studies showed that molecular emission lines can contribute significantly to the measured fluxes in those continuum bands. We use the Heterodyne Array Receiver Programme 12CO J = 3−2 integrated intensity map for Orion A in order to evaluate the molecular line contamination and its effects on the SCUBA-2 maps. With the corrected fluxes, we have obtained a new spectral index α map for the thermal emission of dust in the well-known integral-shaped filament. Furthermore, we compare a sample of 33 sources, selected over the Orion A molecular cloud complex for their high 12CO J = 3−2 line contamination, to 27 previously identified clumps in OMC 4. This allows us to quantify the effect of line contamination on the ratio of 850–450 μm flux densities and how it modifies the deduced spectral index of emissivity β for the dust grains. We also show that at least one Spitzer-identified protostellar core in OMC 5 has a 12CO J = 3−2 contamination level of 16 per cent. Furthermore, we find the strongest contamination level (44 per cent) towards a young star with disc near OMC 2. This work is part of the JCMT Gould Belt Legacy Survey.
Background
Chronic nonextreme sun exposure induces two mechanisms of skin pigmentation, causing immediate darkening and delayed tanning. A new molecule, 2‐mercaptonicotinoyl glycine (2‐MNG), has been ...shown in vitro to inhibit both immediate darkening and new melanin synthesis via covalent conjugation of the thiol group of 2‐MNG to melanin precursors.
Objective
To evaluate 2‐MNG in preventing both mechanisms in vivo.
Methods
In a randomized, intra‐individual and controlled study, 33 subjects with melanin‐rich skin were exposed to UV daylight on designated areas on the back and treated with a cosmetic formula containing 0.5% or 1% 2‐MNG alone or 0.5% 2‐MNG in association with lipohydroxy acid (LHA, 0.3%) plus Mexoryl‐SX (MSX, 1.5%). The respective vehicles were used as controls and 4‐n‐butyl‐resorcinol (4‐n‐BR, 2.5%) as a positive reference.
Results
2‐MNG alone significantly reduced immediate darkening and inhibited new melanin production when compared with vehicle, with higher performance at 1% than at 0.5%. 2‐MNG at 0.5% in association with LHA and MSX showed significantly higher performance than 2‐MNG 0.5% alone. 2‐MNG at 0.5% and 1% showed significantly better performance than 4‐n‐BR.
Conclusions
2‐MNG inhibited both UV‐induced skin pigmentation mechanisms in vivo. The association of 2‐MNG with LHA plus MSX showed the highest efficacy on melanin‐rich skin with pigmentation induced by UV exposure.
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