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International audience; Differences in speakers' voice characteristics, such as mean fundamental frequency (F0) and vocal-tract length (VTL), that primarily define speakers' so-called perceived voice gender facilitate the perception of speech in competing speech. Perceiving speech in competing speech is particularly challenging for children, which may relate to their lower sensitivity to differences in voice characteristics than adults. This study investigated the development of the benefit from F0 and VTL differences in school-age children (4–12 years) for separating two competing speakers while tasked with comprehending one of them and also the relationship between this benefit and their corresponding voice discrimination thresholds. Children benefited from differences in F0, VTL, or both cues at all ages tested. This benefit proportionally remained the same across age, although overall accuracy continued to differ from that of adults. Additionally, children's benefit from F0 and VTL differences and their overall accuracy were not related to their discrimination thresholds. Hence, although children's voice discrimination thresholds and speech in competing speech perception abilities develop throughout the school-age years, children already show a benefit from voice gender cue differences early on. Factors other than children's discrimination thresholds seem to relate more closely to their developing speech in competing speech perception abilities.

Tropical forests are integral to the global carbon, water and energy budgets. However, the magnitude of matter and energy fluxes are poorly resolved both spatially and temporally, and the driving underlying mechanisms by which they occur remain unclear poorly described. Specifically, the diversity of foliar phenological patterns and there influence forest fluxes in the tropics has not been properly studied. As a result of these knowledge gaps, dynamic global vegetation models (DGVMs) consistently fail to exhibit observed productivity dynamics and climate-vegetation feedbacks. These shortcomings prevent reliable predictions on the fate and role of tropical forests under changing climate conditions from being made.Working at perminant tropical forest fieldsites in French Guiana, we demonstrate that biweekly scans with UAV mounted LiDAR and multispecral sensors can observe subtle phenological changes of individual trees across novel spatial scales. We explore the intra- and inter-species variation in phenological behavoirs and link these dynamics to in-situ flux measurements.

International audience; This paper introduces the basic phenomenon of multistability, which occurs when a single physical stimulus produces alternations between different subjective percepts. The phenomenon was first discovered when different images were presented to the two eyes; the perceived image was dominated at any one time by the image presented to one eye, but the percept "flipped" unpredictably, an effect called binocular rivalry. Multistability was later discovered to occur for a wide range of visual stimuli, including those involving apparent motion, and to occur for auditory, tactile and olfactory stimuli. The key features of stimuli leading to multistability are: (i) they have more than one plausible perceptual organisation; (ii) these organisations are not compatible with each other. Most cases of multistability are based on competition in selecting and binding stimulus information. Hence, multistability can be used as a method for studying the binding process in various perceptual modalities. The binding issue is considered here in three different directions: binding sensory information into perceptual scenes for defining perceptual objects in each modality; binding sensory inputs across modalities for addressing questions about multisensory perceptual organisation in the brain; and binding our knowledge of neural processing in various sensory modalities to let emerge new questions, new methods and new models. The paper concludes with an outline of the papers in this issue and with some thoughts about open directions and avenues for further research.

Multiple centrosomes in tumor cells create the potential for multipolar divisions that can lead to aneuploidy and cell death. Nevertheless, many cancer cells successfully divide because of mechanisms that suppress multipolar mitoses. A genome-wide RNAi screen in Drosophila S2 cells and a secondary analysis in cancer cells defined mechanisms that suppress multipolar mitoses. In addition to proteins that organize microtubules at the spindle poles, we identified novel roles for the spindle assembly checkpoint, cortical actin cytoskeleton, and cell adhesion. Using live cell imaging and fibronectin micropatterns, we found that interphase cell shape and adhesion pattern can determine the success of the subsequent mitosis in cells with extra centrosomes. These findings may identify cancer-selective therapeutic targets: HSET, a normally nonessential kinesin motor, was essential for the viability of certain extra centrosome-containing cancer cells. Thus, morphological features of cancer cells can be linked to unique genetic requirements for survival.

This study is the first step in the psychoacoustic exploration of perceptual differences between the sounds of different violins. A method was used which enabled the same performance to be replayed on different "virtual violins," so that the relationships between acoustical characteristics of violins and perceived qualities could be explored. Recordings of real performances were made using a bridge-mounted force transducer, giving an accurate representation of the signal from the violin string. These were then played through filters corresponding to the admittance curves of different violins. Initially, limits of listener performance in detecting changes in acoustical characteristics were characterized. These consisted of shifts in frequency or increases in amplitude of single modes or frequency bands that have been proposed previously to be significant in the perception of violin sound quality. Thresholds were significantly lower for musically trained than for nontrained subjects but were not significantly affected by the violin used as a baseline. Thresholds for the musicians typically ranged from 3 to 6 dB for amplitude changes and 1.5%-20% for frequency changes. Interpretation of the results using excitation patterns showed that thresholds for the best subjects were quite well predicted by a multichannel model based on optimal processing.

International audience; A novel crystalline organic–inorganic hybrid oxovanadium(V) phosphate complex, {[V2O4(Phen)2(PO4)]2VO(OH)}3/4 {[V2O4(Phen)2(HPO4)]2}1/4 · 4.5H2O (where Phen = 1,10-phenanthroline), was isolated using the hydrothermal synthetic approach, and characterised structurally using thermal (TG and DSC) and CHN elemental analysis, vibrational spectroscopy (IR and Raman), single crystal X-ray diffraction and solid-state NMR. The structure contains two similar binuclear dioxovanadium(V) moieties, with all V5+ centres in a highly distorted octahedral coordination geometry. These are further bridged via a fifth V5+ centre, in a highly distorted tetrahedral coordination geometry, leading to the formation of a pentanuclear moiety. Individual complexes close-pack in the solid-state via offset π–π (between neighbouring phenanthroline residues) and hydrogen bonding interactions (with the water molecules of crystallisation). 51V and 31P solid-state NMR proved unequivocally the presence of these two coordination environments for the V5+ centres.

Centrioles and centrosomes have an important role in animal cell organization, but it is uncertain to what extent they are essential for animal development. The Drosophila protein DSas-4 is related to the human microcephaly protein CenpJ and the C. elegans centriolar protein Sas-4. We show that DSas-4 is essential for centriole replication in flies. DSas-4 mutants start to lose centrioles during embryonic development, and, by third-instar larval stages, no centrioles or centrosomes are detectable. Mitotic spindle assembly is slow in mutant cells, and approximately 30% of the asymmetric divisions of larval neuroblasts are abnormal. Nevertheless, mutant flies develop with near normal timing into morphologically normal adults. These flies, however, have no cilia or flagella and die shortly after birth because their sensory neurons lack cilia. Thus, centrioles are essential for the formation of centrosomes, cilia, and flagella, but, remarkably, they are not essential for most aspects of Drosophila development.

Epilepsy is a group of neurological disorders which affects millions of people worldwide. Although treatment with medication is helpful in 70% of the cases, serious side effects affect the quality of life of patients. Moreover, a high percentage of epileptic patients are drug resistant; in their case, neurosurgery or neurostimulation are necessary. Therefore, the major goal of epilepsy research is to discover new therapies which are either capable of curing epilepsy without side effects or preventing recurrent seizures in drug-resistant patients. Neuroengineering provides new approaches by using novel strategies and technologies to find better solutions to cure epileptic patients at risk. As a demonstration of a novel experimental protocol in an acute mouse model of epilepsy, a direct in situ electrophoretic drug delivery system is used. Namely, a neural probe incorporating a microfluidic ion pump (µFIP) for on-demand drug delivery and simultaneous recording of local neural activity is implanted and demonstrated to be capable of controlling 4-aminopyridine-induced (4AP-induced) seizure-like event (SLE) activity. The γ-aminobutyric acid (GABA) concentration is kept in the physiological range by the precise control of GABA delivery to reach an antiepileptic effect in the seizure focus but not to cause overinhibition-induced rebound bursts. The method allows both the detection of pathological activity and intervention to stop seizures by delivering inhibitory neurotransmitters directly to the epileptic focus with precise spatiotemporal control. As a result of the developments to the experimental method, SLEs can be induced in a highly localized manner that allows seizure control by the precisely tuned GABA delivery at the seizure onset.