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Addictions often develop in a social context, although the influence of social factors did not receive much attention in the neuroscience of addiction. Recent animal studies suggest that peer presence can reduce cocaine intake, an influence potentially mediated, among others, by the subthalamic nucleus (STN). However, there is to date no neurobiological study investigating this mediation in humans. This study investigated the impact of social context and drug cues on brain correlates of inhibitory control in individuals with and without cocaine use disorder (CUD) using functional Magnetic Resonance Imaging (fMRI). Seventeen CUD participants and 17 healthy controls (HC) performed a novel fMRI “Social” Stop-Signal Task (SSST) in the presence or absence of an observer while being exposed to cocaine-related (vs. neutral) cues eliciting craving in drug users. The results showed that CUD participants, while slower at stopping with neutral cues, recovered control level stopping abilities with cocaine cues, while HC did not show any difference. During inhibition (Stop Correct vs Stop Incorrect), activity in the right STN, right inferior frontal gyrus (IFG), and bilateral orbitofrontal cortex (OFC) varied according to the type of cue. Notably, the presence of an observer reversed this effect in most areas for CUD participants. These findings highlight the impact of social context and drug cues on inhibitory control in CUD and the mediation of these effects by the right STN and bilateral OFC, emphasizing the importance of considering the social context in addiction research. They also comfort the STN as a potential addiction treatment target.

The “voice areas” in the superior temporal cortex have been identified in both humans and non-human primates as selective to conspecific vocalizations only (i.e., expressed by members of our own species), suggesting its old evolutionary roots across the primate lineage. With respect to non-human primate species, it remains unclear whether the listening of vocal emotions from conspecifics leads to similar or different cerebral activations when compared to heterospecific calls (i.e., expressed by another primate species) triggered by the same emotion. Using a neuroimaging technique rarely employed in monkeys so far, functional Near Infrared Spectroscopy, the present study investigated in three lightly anesthetized female baboons (Papio anubis), temporal cortex activities during exposure to agonistic vocalizations from conspecifics and from other primates (chimpanzees—Pan troglodytes), and energy matched white noises in order to control for this low-level acoustic feature. Permutation test analyses on the extracted OxyHemoglobin signal revealed great inter-individual differences on how conspecific and heterospecific vocal stimuli were processed in baboon brains with a cortical response recorded either in the right or the left temporal cortex. No difference was found between emotional vocalizations and their energy-matched white noises. Despite the phylogenetic gap between Homo sapiensand African monkeys, modern humans and baboons both showed a highly heterogeneous brain process for the perception of vocal and emotional stimuli. The results of this study do not exclude that old evolutionary mechanisms for vocal emotional processing may be shared and inherited from our common ancestor.

Platinum is the most active anode and cathode catalyst in next-generation fuel cells using methanol as liquid source of hydrogen. Its catalytic activity can be significantly improved by alloying with 3d metals, although a precise tuning of its surface architecture is still required. Herein, we report the design of a highly active low-temperature (below 0 °C) methanol dehydrogenation anode catalyst with reduced CO poisoning based on ultralow amount of precisely defined PtxNi1–x(x= 0 to 1) bimetallic clusters (BCs) deposited on inert flat oxides by cluster beam deposition. These BCs feature clear composition-dependent atomic arrangements and electronic structures stemming from their nucleation mechanism, which are responsible for a volcano-type activity trend peaking at the Pt0.7Ni0.3composition. Our calculations reveal that at this composition, a cluster skin of Pt atoms with d-band centers downshifted by subsurface Ni atoms weakens the CO interaction that in turn triggers a significant increase in the methanol dehydrogenation activity.

Ag clusters (AgCLs) confined within Na-exchanged Linde type A zeolites are studied by X-ray absorption and steady-state and time-resolved photoluminescence spectroscopies in a coordinated effort to elucidate the photophysical properties and link them to the precise cluster structure. The hydrated sodalite cage contains mostly tetrahedral [Ag4(H2O)4] clusters located at the center of the sodalite cages, whereas octahedral Ag6clusters coordinated with the zeolite framework oxygen (OF) [Ag6(OF)14] are formed upon dehydration. The time-dependent density functional theory and electron spin resonance reports suggest that both Ag4and Ag6clusters have formally a double positive charge of 2+. Time-resolved spectroscopy shows that at room temperature, the emission of the hydrated sample decays with 3.4 ns from a state with the same multiplicity as the ground state. Upon dehydration, the entire excited-state dynamics speeds up to 1.2 ps. The microsecond-scale lifetimes observed at 77 K suggest the occurrence of two main decay processes for the initially populated singlet state: intersystem crossing and charge transfer. We show that the intersystem crossing yields the formation of a long-lived (409 μs) triplet state 3P from the 1P state located at lower energy from which luminescence occurs. There is evidence that electron transfer is followed by electron–hole recombination or back electron transfer, yielding a relaxed singlet excited state. Upon removal of water ligands, the electrostatic field of the framework is enhanced, which leads to an increase in the rate constant of charge transfer due to stronger electronic coupling between Ag62+and trap levels. The dependence of luminescence lifetime on the water content indicates a possible way to speed or delay the electron–hole recombination in a controlled way.

Metal clusters confined inside zeolite frameworks display unique electronic, catalytic, and optical properties. However, so far only confined silver clusters have shown peculiar luminescent properties, displaying high photoluminescent quantum efficiencies reaching almost unity. In this study, we demonstrate the self-assembly and confinement of highly luminescent lead (Pb) clusters into the molecular-sized cavities of Linde Type A (LTA) zeolites. These Pb-LTA samples display an intense deep-blue emission with external quantum efficiencies up to 69% in their partially dehydrated state. A tetrahedral lead cluster (Pb4) with unusually short Pb–Pb distances and hydroxyl ligands was identified as responsible for the luminescence as determined by X-ray absorption fine structure (XAFS) analysis. The in-depth characterization of the Pb-zeolites, reported here, sets the stage for elucidating the structure-to-luminescent relationship of other zeolite-embedded clusters.

This study quantitatively elucidates the role of metal clusters in the electrochemical activation of metal-oxide nanostructured electrodes. Through the deposition of nearly monodisperse AuxPt1–x(x= 0, 0.5, 1) clusters, smaller than 3 nm, on the ZnO nanorod (NR) electrode surface, a controlled enhancement of charge transfer and activation of electrocatalytic processes was achieved. The interfacial electrical states of the hybrid electrodes were probed by electrochemical impedance spectroscopy (EIS). Analysis of the charge-transfer resistance and interface capacitance, estimated by modeling EIS curves in different bias regimes, indicated the presence of a large amount of active donor states (∼1020cm–3) at the surface of the ZnO NRs. Decoration of the ZnO NRs with AuxPt1–xclusters strongly increased the charge-transfer process at the cluster–ZnO/electrolyte interface. This induced a more effective depletion of the electron charge available in the donor states of the ZnO NRs, leading to the formation of a positively charged layer at the interface between ZnO and the clusters. These two effects, intrinsically linked with the alignment between the electronic states of the AuxPt1–xclusters and ZnO, strongly enhance the interface reactivity of the ZnO NR electrodes toward the redox reaction of potassium ferricyanide. This is particularly relevant for understanding and improving the performance of electrochemical biosensors.

Discriminating between auditory signals of different affective value is critical to successful social interaction. It is commonly held that acoustic decoding of such signals occurs in the auditory system, whereas affective decoding occurs in the amygdala. However, given that the amygdala receives direct subcortical projections that bypass the auditory cortex, it is possible that some acoustic decoding occurs in the amygdala as well, when the acoustic features are relevant for affective discrimination. We tested this hypothesis by combining functional neuroimaging with the neurophysiological phenomena of repetition suppression (RS) and repetition enhancement (RE) in human listeners. Our results show that both amygdala and auditory cortex responded differentially to physical voice features, suggesting that the amygdala and auditory cortex decode the affective quality of the voice not only by processing the emotional content from previously processed acoustic features, but also by processing the acoustic features themselves, when these are relevant to the identification of the voice's affective value. Specifically, we found that the auditory cortex is sensitive to spectral high-frequency voice cues when discriminating vocal anger from vocal fear and joy, whereas the amygdala is sensitive to vocal pitch when discriminating between negative vocal emotions (i.e., anger and fear). Vocal pitch is an instantaneously recognized voice feature, which is potentially transferred to the amygdala by direct subcortical projections. These results together provide evidence that, besides the auditory cortex, the amygdala too processes acoustic information, when this is relevant to the discrimination of auditory emotions.

The integration of metal atoms and clusters in well-defined dielectric cavities is a powerful strategy to impart new properties to them that depend on the size and geometry of the confined space as well as on metal–host electrostatic interactions. Here, we unravel the dependence of the electronic properties of metal clusters on space confinement by studying the ionization potential of silver clusters embedded in four different zeolite environments over a range of silver concentrations. Extensive characterization reveals a strong influence of silver loading and host environment on the cluster ionization potential, which is also correlated to the cluster’s optical and structural properties. Through fine-tuning of the zeolite host environment, we demonstrate photoluminescence quantum yields approaching unity. This work extends our understanding of structure–property relationships of small metal clusters and applies this understanding to develop highly photoluminescent materials with potential applications in optoelectronics and bioimaging.

Under theories of embodied emotion, exposure to a facial expression triggers facial mimicry. Facial feedback is then used to recognize and judge the perceived expression. However, the neural bases of facial mimicry and of the use of facial feedback remain poorly understood. Furthermore, gender differences in facial mimicry and emotion recognition suggest that different neural substrates might accompany the production of facial mimicry, and the processing of facial feedback, in men and women. Here, repetitive transcranial magnetic stimulation (rTMS) was applied to the right primary motor cortex (M1), the right primary somatosensory cortex (S1), or, in a control condition, the vertex (VTX). Facial mimicry of smiles and emotion judgments were recorded in response to video clips depicting changes from neutral or angry to happy facial expressions. While in females rTMS over M1 and S1 compared to VTX led to reduced mimicry and, in the case of M1, delayed detection of smiles, there was no effect of TMS condition for males. We conclude that in female participants M1 and S1 play a role in the mimicry and in the use of facial feedback for accurate processing of smiles.

The effect of the growth temperature and the Ga precursor flow on the epitaxy of Si1-xGex:Ga is studied. These parameters are found to have a significant impact on the Ga surface segregation behavior. In particular, Ga in situdoping impacts the growth rate of the epilayer, the Si1-xGexalloy composition, and the onset of strain relaxation. The growth temperature can be used to modulate the Ga segregation, enabling the deposition of materials with enhanced dopant concentrations and improved electrical properties. The Ga local atomic environment was studied in both a Si0.4Ge0.6:Ga and a Ge:Ga sample by X-ray absorption fine structure. The local environment of the Ga determined confirmed that the majority of dopants occupy a substitutional position within the lattice.

Subthalamic nucleus (STN) deep brain stimulation in Parkinson's disease induces modifications in the recognition of emotion from voices (or emotional prosody). Nevertheless, the underlying mechanisms are still only poorly understood, and the role of acoustic features in these deficits has yet to be elucidated. Our aim was to identify the influence of acoustic features on changes in emotional prosody recognition following STN stimulation in Parkinson's disease. To this end, we analysed the performances of patients on vocal emotion recognition in pre-versus post-operative groups, as well as of matched controls, entering the acoustic features of the stimuli into our statistical models. Analyses revealed that the post-operative biased ratings on the Fearscale when patients listened to happy stimuli were correlated with loudness, while the biased ratings on the Sadnessscale when they listened to happiness were correlated with fundamental frequency (F0). Furthermore, disturbed ratings on the Happinessscale when the post-operative patients listened to sadness were found to be correlated with F0. These results suggest that inadequate use of acoustic features following subthalamic stimulation has a significant impact on emotional prosody recognition in patients with Parkinson's disease, affecting the extraction and integration of acoustic cues during emotion perception.

In our study, two groups of participants (n = 61 and n = 58) listened to nine pieces for solo violin and rated how they felt along an affect dimension and along the nine Geneva Emotional Music Scale dimensions. After each piece, they completed a 12-item questionnaire corresponding to subjective entrainment reports. A factorial analysis of this Musical Entrainment Questionnaire revealed a two-factor solution, with Visceral Entrainment (VE) corresponding to sensations of internal bodily entrainment and Motor Entrainment (ME) reflecting participants’ inclination to move to the beat. These findings represent, to the best of our knowledge, the first empirical evidence for the existence of two components underlying entrainment capable of predicting specific emotional responses to music. Indeed, although both factors predicted Affect, Joyful activation, Transcendence, Wonder, Power, and Tenderness dimensions, only VE predicted Nostalgia and Sadness. Moreover, Peacefulness was mostly predicted by ME, whereas Tension was mostly predicted by VE.

Emotional states can influence the human voice during speech utterances. Here, we tested the sensitivity and signal adaptation of functional activity located in amygdala subregions to threatening voices during high-resolution functional magnetic resonance imaging. Bilateral superficial (SF) complex and the right laterobasal (LB) complex of the amygdala were generally sensitive to emotional cues from speech prosody. Activity was stronger, however, when listeners directly focused on the emotional prosody of the voice instead of attending to a nonemotional feature. Explicit attention to prosody especially elicited activity in the right LB complex. Furthermore, the right SF specifically showed an effect of sensitization indicated by a significant signal increase in response to emotional voices which were preceded by neutral events. The bilateral SF showed signal habituation to repeated emotional voices indicated by a significant signal decrease for an emotional event preceded by another emotional event. The right SF and LB finally showed an effect of desensitization after the processing of emotional voices indicated by a signal decrease for neutral events that followed emotional events. Thus, different amygdala subregions are sensitive to threatening emotional voices, and their activity depends on the attentional focus as well as on the proximal temporal context of other neutral and emotional events.

In situ X-ray absorption spectroscopy XAFS at the Cu and Zn K-edge has been used to unravel the Cu/Zn interaction and identify the possible active site of Cu-based methanol synthesis catalysts in the Cu/ZnO/SiO2ternary system. These highly dispersed silica supported catalysts, whose activity increases sharply as a function of the reduction temperature, were studied calcined, reduced at 200, 300, and 400 °C, and for each reduction temperature under passivation/rereduction and methanol synthesis conditions. Results showed that the calcined form consists mainly of a mixed Cu/Zn hydrosilicate that is progressively transformed as the reduction temperature increases into (i) Cu metal particles, (ii) increasingly dispersed ZnO species on SiO2, and (iii) finally a Zn metallic phase forming segregated bimetallic Cu–Zn α-brass alloy particles. These different structures and Cu/Zn interfaces may correspond to different active phases and activities in methanol synthesis. After reduction at 200 and 300 °C, Cu0is likely composing most of the active phase, whereas above 300 °C, the sharp increase in the number Zn0-based sites formed as a function of the reduction temperature could explain the major role played by this parameter in controlling the activity of these catalysts. The dynamic Cu/Zn interaction as a function of the temperature and gas environment pointed out in this ternary system may be at the origin of the existence of different and sometimes contradictory models to account for the mechanisms of the methanol synthesis.

Appraisal theorists suggest that the face expresses cognitive processes involved both in the orienting of attention (primarily gaze direction) and in the evaluation of emotion-eliciting events. Contrary to the assumption of direct emotion recognition by basic emotions theorists, this implies an interaction effect between “perceived gaze direction” and “perceived facial expression” in inferring emotion from the face. These two theoretical perspectives were comparatively tested by requesting participants to decode dynamic synthetic facial expressions of emotion presented with either an averted or a direct gaze. Confirming the interaction predicted by appraisal theories, the perceived specificity and intensity of fear and anger depended on gaze direction (direct gaze for anger and averted gaze for fear).

Platinum and palladium surface doped tin nanoparticles have been obtained by decomposition of [Pt2(dba)3] and [Pd(dba)2] organometallic precursors, respectively, in a colloidal suspension of tin/tin oxide core–shell nanoparticles of uniform size (13 nm), in anisole under 1 bar of carbon monoxide at room temperature. The particles can be isolated as pure solids and present effective doping ratios [Pt]/[Sn] and [Pd]/[Sn] of 2.5 and 3.1%, respectively. These nanomaterials have been characterized by means of transmission electron and high-resolution transmission electron microscopies (TEM and HRTEM), Energy Dispersive X-ray spectroscopy (EDX), photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (EXAFS and XANES). The TEM micrographs show spherical nanoparticles whose size and size distribution are essentially similar to those of the initial Sn/SnOxmaterial. HRTEM, EDX, XPS and X-ray absorption spectroscopy (XAS) studies at the Pd and/or Sn-K edge show the conservation of the composite nature of the particles that consist of a tin(0) core covered with a layer of tin oxides on which the doping element is deposited under the form of crystalline metallic platelets of size near 2 nm. The thermal oxidation of these Pt- or Pd-doped tin materials yields nanoparticles of crystallized SnO2covered with crystallites of Pt or Pd oxides, as demonstrated by XRD, XPS and XAS experiments, without coalescence or size change. In the oxidised Pd-doped material, EXAFS analysis combined with HRTEM, point towards the formation of two main Pd disordered oxide phases: a rather pure oxopalladate Pd3.5O4-type phase at the surface of the particle and a mixed Pd/Sn phase having a PdO structure-type at the interface Pd oxide/Sn oxide. The thermal oxidation process can be easily achieved onto the silicon platform of a micro-machined device after integration of the Pt- or Pd-doped Sn/SnOxcolloidal suspension by drop deposition. The first electrical measurements indicate remarkable behaviours of the as-obtained microsensors when exposed to traces of carbon monoxide. In addition to the expected large increase of sensitivity of the doped relatively to the undoped sensitive layer measured in humid atmosphere, a surprising and unprecedented inversion of sensitivity from undoped to Pt- and Pd-doped sensors has been observed in dry atmosphere.

STEM-EELS and EXAFS have been used to investigate the location and electronic state of Mn as promoter in TiO2-supported cobalt Fischer–Tropsch catalysts prepared by two different procedures. It was found that the extent of interaction between Mn and the active Co phase as well as the level of Mn dispersion over the TiO2surface largely determine the enhancement of the selectivity in the Fischer–Tropsch synthesis at pressures of 1 bar.

Samples with 5.1%, 9.8% and 15.3% HbA1c were extracted from normal subjects and patients with slight and serious diabetes respectively. Extended x-ray absorption fine structure spectra of Fe K absorption were collected at the EXAFS experimental station of the Beijing Synchrotron Radiation Facility. The step-by-step fluorescent mode was employed with a count time of 10 s per point. Several independent scans were averaged to eliminate the statistical noise. Reference backscattering amplitudes and phaseshifts were calculated using the curve wave theory (FEFF code) of EXAFS. Apart from the nitrogen neighbours around the central iron atom, oxygen neighbours are also found. The Fe-N bond length increases by about 0.02 Å for the sample with 15.3% HbA1c compared with the others, but the Fe-O bond length is almost unchanged. With increasing of HbA1c concentration, the content of Hb increases and the content of HbO2decreases. This demonstrates that the glycosylation of haemoglobin will decrease its ability to carry oxygen.

An abstract of the research "A Systems Approach to Appraisal Mechanisms in Emotion," by David Sander, Didier Grandjean, and Klaus R. Scherer is presented.

An in situcell, which is capable of obtaining time resolved soft X-ray data (200 eV < E< 3000 eV) under hydrothermal conditions has been developed and used to study the self-assembly processes occurring during microporous aluminophosphate crystallization.