Thiol S-Conjugate Profiles: A Comparative Investigation on Dual Hop and Grape Must with Focus on Sulfanylalkyl Aldehydes and Acetates Adducts

Cysteinylated and glutathionylated precursors of sulfanylalkyl alcohols have been extensively studied in hop and grape matrices, in contrast to those of sulfanylalkyl aldehydes and sulfanylalkyl acetates. Here, cysteinylated and glutathionylated adducts of 3-sulfanylpentanal (Cys-3SPal and G-3SPal), 3-sulfanylhexanal (Cys-3SHal and G-3SHal), 3-sulfanylpentyl acetate (only Cys-3SPA), and 3-sulfanylhexyl acetate (Cys-3SHA and G-3SHA) were first synthesized. Next, the occurrence of these compounds was studied by RP-HPLC-ESI(+)-MRM and apotryptophanase-GC-PFPD in a few dual hops and Belgian grape must samples. None of the Cys-adducts of 3-sulfanylalkyl aldehydes were detected in hop or grape extracts, while G-3SPal was identified for the first time in a natural matrix. Concentrations ranging from 3 to 15mg/kg were found in several hop varieties, including Citra, Mandarina Bavaria, Mosaic, Nelson Sauvin, Polaris, and Saaz, whereas G-3SHal was detected (below the quantitation limit) only in the four latters. As for esters, Cys-3SPA was found in hop (4mg/kg in Mosaic), while G-3SHA was detected only in grape extracts (Belgian Chardonnay and Johanniter). Besides the ubiquitous G-3SHol, G-3SPol was identified here for the first time in grape must (up to 7mg/kg in Johanniter)

Functional Connectivity Within the Fronto-Parietal Network Predicts Complex Task Performance: A fNIRS Study

International audiencePerformance in complex tasks is essential for many high risk operators. The achievement of such tasks is supported by high-level cognitive functions arguably involving functional activity and connectivity in a large ensemble of brain areas that form the fronto-parietal network. Here we aimed at determining whether the functional connectivity at rest within this network could predict performance in a complex task: the Space Fortress video game. Functional Near Infrared Spectroscopy (fNIRS) data from 32 participants were recorded during a Resting-State period, the completion of a simple version of Space Fortress (monotask) and the original version (multitask). The intrinsic functional connectivity within the fronto-parietal network (i.e., during the Resting-State) was a significant predictor of performance at Space Fortress multitask but not at its monotask version. The same pattern was observed for the functional connectivity during the task. Our overall results suggest that Resting-State functional connectivity within the fronto-parietal network could be used as an intrinsic brain marker for performance prediction of a complex task achievement, but not for simple task performance

Magnetotransport in a two-subband AlGaN/GaN heterostructure in the presence of mixed disorder

We present magnetotransport measurements on a high electron density AlGaN/GaN heterostructure with two subbands populated at T = 1.6 K. The transport scattering times, τtr, of each subband are first derived at low magnetic field by taking into account the magneto-intersubband scattering term. Then the quantum scattering times, τq, are extracted from independent Dingle plots, obtained at higher magnetic fields. All scattering times are studied as a function of the total electronic density, increased by the persistent photo-conductivity effect. A standard modelization, based on all common scattering mechanisms, reveals that the transport scattering time is governed by the short-range AlGaN/GaN interface roughness (IR) scattering, whereas the quantum scattering time is due to the smooth potential induced by remote ionized impurities (II) at the GaN surface. This intermediate situation of mixed disorder, where the τtr/τq ratio is greater than one, does not indicate that the mobility is limited by Coulomb scattering. It is due to the unusual condition, ${\tau }_{\mathrm{t}r}^{\mathrm{II}}\gg {\tau }_{\mathrm{t}r}^{\mathrm{IR}}\gg {\tau }_{\mathrm{q}}^{\mathrm{II}}$

Development of technological building blocks for the monolithic integration of ammonia-MBE-grown GaN-HEMTs with silicon CMOS

International audienc

Performance after training in a complex cognitive task is enhanced by high-definition transcranial random noise stimulation

International audienceInterest for neuromodulation, and transcranial random noise stimulation (tRNS) in particular, is growing. It concerns patients rehabilitation, but also healthy people who want or need to improve their cognitive and learning abilities. However, there is no consensus yet regarding the efficacy of tRNS on learning and performing a complex task. In particular, the most effective electrode montage is yet to be determined. Here, we examined the effect of two different tRNS montages on learning rate, short- and long-term performance in a video game (Space Fortress) that engages multiple cognitive abilities. Sixty-one participants were randomly assigned to one of three groups (sham vs. simple-definition tRNS vs. high-definition tRNS) in a double-blind protocol. Their performance on the Space Fortress task was monitored during a 15-day experiment with baseline (day 1), stimulation (day 2 to 4), short- (day 5) and long-term (day 15) evaluations. Our results show that the high-definition tRNS group improved more on the long term than simple-definition tRNS group, tended to learn faster and had better performance retention compared to both simple-definition tRNS and sham groups. This study is the first to report that high-definition tRNS is more effective than conventional simple-definition tRNS to enhance performance in a complex task

Designing SiC Based CMUT Structures: An Original Approach and Related Material Issues

We present an epitaxy-based approach for designing a 3C-SiC Capacitive Micromachined Ultrasonic Transducer (CMUT). The design requires to consider a 3C-SiC/Si/3C-SiC heterostructure on a Si substrate. This implies to address different growth steps of SiC on Si and Si on SiC. We present some specific growth related issued, namely the control of selectively grown Si on a masked SiC(100) and the further regrowth of 3C-SiC on a Si (110) layer. The final release of the SiC membrane, to define a CMUT, is also addressed using a simple thermal treatment allowing to suppress several technological steps

UVB LEDs Grown by Molecular Beam Epitaxy Using AlGaN Quantum Dots

AlGaN based light emitting diodes (LEDs) will play a key role for the development of applications in the ultra-violet (UV). In the UVB region (280–320 nm), phototherapy and plant lighting are among the targeted uses. However, UVB LED performances still need to be improved to reach commercial markets. In particular, the design and the fabrication process of the active region are central elements that affect the LED internal quantum efficiency (IQE). We propose the use of nanometer-sized epitaxial islands (i.e., so called quantum dots (QDs)) to enhance the carrier localization and improve the IQE of molecular beam epitaxy (MBE) grown UVB LEDs using sapphire substrates with thin sub-µm AlN templates. Taking advantage of the epitaxial stress, AlGaN QDs with nanometer-sized (≤10 nm) lateral and vertical dimensions have been grown by MBE. The IQE of the QDs has been deduced from temperature dependent and time resolved photoluminescence measurements. Room temperature IQE values around 5 to 10% have been found in the 290–320 nm range. QD-based UVB LEDs were then fabricated and characterized by electrical and electroluminescence measurements. On-wafer measurements showed optical powers up to 0.25 mW with external quantum efficiency (EQE) values around 0.1% in the 305–320 nm range

FIG. 11 in Nouvelles données géologiques et biostratigraphiques du gisement paléontologique à vertébrés de Mauvières, à Marcilly-sur-Maulne (Miocène inférieur et moyen; Indre-et-Loire, France)

FIG. 11. — Mandibules droites du lacertidé Ligerosaurus pouiti (Augé, Bailon & Malfay, 2003) des sables de l'Orléanien (MN3) du site de Mauvières (Indre-et-Loire, France): A, ULB-MAUV-9; B, ULB-MAUV-10. Échelles: 0,5 cm.Published as part of Gagnaison, Cyril, Mennecart, Bastien, Bailleul, Julien, Barrier, Pascal, Chenot, Élise, Toullec, Renaud, Potel, Sébastien, Martin, Honoré, Millet, Antoine & Memeteau, Didier, 2023, Nouvelles données géologiques et biostratigraphiques du gisement paléontologique à vertébrés de Mauvières, à Marcilly-sur-Maulne (Miocène inférieur et moyen; Indre-et-Loire, France), pp. 449-478 in Geodiversitas 45 (16) on page 463, DOI: 10.5252/geodiversitas2023v45a16, http://zenodo.org/record/834392

Lacertidae Oppel 1811

Famille LACERTIDAE Oppel, 1811 – Ligerosaurus pouiti (Augé, Bailon & Malfay, 2003): hémimandibule d. (ULB-MAUV-9; Fig. 11), hémimandibule d. (ULB-MAUV-10; Fig.11), une hémimandibule d. (Coll.DM); – Lacertidae indet.: une hémimandibule d. (ULB-MAUV-11).Published as part of Gagnaison, Cyril, Mennecart, Bastien, Bailleul, Julien, Barrier, Pascal, Chenot, Élise, Toullec, Renaud, Potel, Sébastien, Martin, Honoré, Millet, Antoine & Memeteau, Didier, 2023, Nouvelles données géologiques et biostratigraphiques du gisement paléontologique à vertébrés de Mauvières, à Marcilly-sur-Maulne (Miocène inférieur et moyen; Indre-et-Loire, France), pp. 449-478 in Geodiversitas 45 (16) on page 475, DOI: 10.5252/geodiversitas2023v45a16, http://zenodo.org/record/834392