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Plastic pollution is pervasive in world oceans and has gained large attention by the media, the public and the governments. The urgency of this issue was recognized by nearly 200 countries that signed in December 2017 in Nairobi the U.N. draft Resolution on Marine Litter and Microplastics. It encourages Member States and stakeholders to take action but despite acknowledging the problem, the resolution does not contain any legally binding agreement.Meanwhile plastic litter continues to accumulate in world oceans. It has been estimated that 8 million tons (Mt) of plastic waste reaches the ocean each year, and with no action that volume is projected to double by 2030, and double again by 2050. In order to tackle this issue, NGOs, startups, activists, public and private decision makers need correct information about the reality of plastic pollution in the sea, its impacts on marine ecosystems and human health. Among the large quantity of information available, it is difficult to differentiate exaggerated alarms from miracle solutions, while taking into account unknown but potential risks of plastic pollution. Scientific evidence shows a complex reality.In order to increase overall scientific literacy on plastic pollution, the associated risks and the possible solutions, thecamp, the new innovation campus located in Aix-en-Provence, France, has created the Plastic and Ocean Platform with the view of bringing together and promoting collaboration between scientists, NGOs and plastic experts.The goal of the Platform, supported by the Intergovernmental Oceanographic Commission of UNESCO, is to facilitate the exchange of information and provide a clear and comprehensible overview of the current scientific knowledge and understanding about plastic pollution and the way to fight it. This information will be shared widely to the media, the general public and the decision makers. As of today, more than 30 international research scientists and 20 NGOs have contributed to the Plastic and Ocean Platform. We are now expanding this network.The first production of the Plastic and Ocean Platform is a state of the art on what is known and what is not known about plastic pollution. Following a collective work with the NGOs, the scientists have produced a scientific summary that gives synthetic answers to the most common questions the public is asking on the reality of plastic pollution and its consequences.

Commentaires: Production issue d’un séminaire de 2 jours à ‘The Camp’, https://thecamp.fr/en/document/pop2018

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DOI: 10.1109/IRMMW-THz.2018.8510039
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We report on the temperature-dependent magneto absorption and magnetotransport spectroscopy of HgTe/CdHgTe quantum wells above the critical well thickness d(c). Our results, obtained in magnetic fields up to 16 T and temperature range from 1.7 to 150 K, clearly indicate a change in the band-gap energy with temperature. A topological phase transition between quantum spin Hall and trivial insulator states, revealing appearance of single-valley Dirac fermions at T = 27 and 90 K for 6.5 and 8 nm QWs respectively, was clearly observed in our magnetospectroscopy measurements.

Commentaires: 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Nagoya, JAPAN, SEP 09-14, 2018

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A few years ago, we demonstrated that graphene can markedly surpass GaAs/AlGaAs semiconductor heterostructures for the implementation of the quantum Hall resistance standard in relaxed experimental conditions, while preserving a state-of-the-art accuracy [1]. This paper describes supplementary quantum transport experiments performed on a significant number of graphene based quantum Hall devices obtained from graphene grown by CVD on SiC, like the one used for the above-mentioned demonstration, and with similar process and preparation. The objectives were to investigate the sample-to-sample reproducibility of the electronic properties and device performance, the structural key control parameter and the underpinning physics.

Commentaires: Conference on Precision Electromagnetic Measurements (CPEM), Paris, FRANCE, JUL 08-13, 2018

Ref HAL: hal-01826289_v1
DOI: 10.3390/cryst8050184
WoS: 000435192500003
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The high-pressure behavior of LuFe2O4 is characterized based on synchrotron X-ray diffraction and neutron diffraction, resistivity measurements, X-ray absorption spectroscopy and infrared spectroscopy studies. The results obtained enabled us to propose a P-T phase diagram. In this study, the low pressure charge-ordering melting could be detected by synchrotron XRD in the P-T space. In addition to the ambient pressure monoclinic C2/m and rhombohedral R(3) over bar m phases, the possible P (1) over bar triclinic phase, the monoclinic high pressure form Pm and metastable modulated monoclinic phases were observed; the latter modulated monoclinic phases were not observed in the present neutron diffraction data. Furthermore, the transition to the Pm phase which was already characterized by strong kinetics is found to be favored at high temperature (373 K). Based on X-ray absorption spectroscopy data the Pm phase, which could be recovered at atmospheric pressure, can be explained by a change in the Fe-local environment from a five-fold coordination to a distorted 5 + 1 one.

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PMID 30053516
DOI: 10.1016/j.neuroimage.2018.07.058
WoS: 000447750200004
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External information can modify the subjective value of a tasted stimulus, but little is known about neural mechanisms underlying these behavioral modifications. This study used flavored drinks to produce variable degrees of discrepancy between expected and received flavor. During a learning session, 43 healthy young men learned 4 symbol-flavor associations. In a separate session, associations were presented again during an fMRI scan, but half of the trials introduced discrepancy with previously learned associations. Liking ratings of drinks were collected and were analyzed using a linear model to define the degree to which discrepant symbols affected liking ratings of the subjects during the fMRI session. Based on these results, a GLM analysis of fMRI data was conducted to determine neural correlates of observed behavior. Groups of subjects were composed based on their behavior in response to discrepant symbols, and comparison of brain activity between groups showed that activation in the PCC and the caudate nucleus was more potent in those subjects in which liking was not affected by discrepant symbols. These activations were not found in subjects who assimilated unexpected flavors to flavors preceeded by discrepant symbols. Instead, these subjects showed differences in the activity in the parietal operculum. The activity of reward network appears to be related to assimilation of received flavor to expected flavor in response to symbol-flavor discrepancy.