The brain's temporal dynamics from a collective decision to individual action

Social animals constantly make decisions together. What determines if individuals will subsequently adjust their behavior to align with collective choices? Here, using functional magnetic resonance imaging in humans, we characterize a novel temporal model of brain response from the time a collective decision is made to the time an individual action is required. We reveal that whether a behavioral modification will occur is determined not necessarily by the brain’s response to the initial social influence, but by how that response(specifically in the orbitofrontal cortex; OFC) is mirrored at a later time when the individual selects their own action. This result suggests that the OFC may reconstitute an initial state of collective influence when individual action is subsequently needed. Importantly, these dynamics vary across individuals as a function of trait conformity and mediate the relationship between this personality characteristic and behavioral adjustment toward the group

An extremal problem for the Bergman kernel of orthogonal polynomials

Let $\Gamma \subset \mathbb C$ be a curve of class $C(2,\alpha)$. For $z_{0}$ in the unbounded component of ${\mathbb C}\setminus \Gamma$, and for $n=1,2,...$, let $\nu_n$ be a probability measure with supp$(\nu_{n})\subset \Gamma$ which minimizes the Bergman function $B_{n}(\nu,z):=\sum_{k=0}^{n}|q_{k}^{\nu}(z)|^{2}$ at $z_{0}$ among all probability measures $\nu$ on $\Gamma$ (here, $\{q_{0}^{\nu},\ldots,q_{n}^{\nu}\}$ are an orthonormal basis in $L^2(\nu)$ for the holomorphic polynomials of degree at most $n$). We show that $\{\nu_{n}\}_n$ tends weak-* to $\hat\delta_{z_{0}}$, the balayage of the point mass at $z_0$ onto $\Gamma$, by relating this to an optimization problem for probability measures on the unit circle. Our proof makes use of estimates for Faber polynomials associated to $\Gamma$.Comment: To appear in Constructive Approximatio

Study of Ironless Permanent Magnet Devices Being Both a Coupling and an Axial Bearing for Naval Propulsion

This paper describes the study of an original permanent magnet device. This device works as both a coupling and as axial bearing. It can be particularly useful in naval propulsion application to transmit the torque without any contact between a motor axis and the propeller and to maintain the propeller in its axial position, compensating the axial force related to thrust. Two kinds of devices are studied for this type of specification. The first corresponds to the classical structure of cylindrical air-gap coupling. The second is an original structure where pairs of rings of axially magnetized magnets are stacked on each rotor. The computation of the behavior of the device (torque and axial force) is done using a semi-analytical method based on magnetic charge theory. This method allows a very fast calculation of the performances of the devices. This study shows the interest of the stacked structure this type of application

Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre

The mechanisms of microbial nitrous oxide (N<sub>2</sub>O) production in the ocean have been the subject of many discussions in recent years. New isotopomeric tools can further refine our knowledge of N<sub>2</sub>O sources in natural environments. This study compares hydrographic, N<sub>2</sub>O concentration, and N<sub>2</sub>O isotopic and isotopomeric data from three stations along a coast-perpendicular transect in the South Pacific Ocean, extending from the center (Sts. GYR and EGY) of the subtropical oligotrophic gyre (~26° S; 114° W) to the upwelling zone (St. UPX) off the central Chilean coast (~34° S). Although AOU/N<sub>2</sub>O and NO<sub>3</sub><sup>−</sup> trends support the idea that most of the N<sub>2</sub>O (mainly from intermediate water (200–600 m)) comes from nitrification, N<sub>2</sub>O isotopomeric composition (intramolecular distribution of <sup>15</sup>N isotopes) expressed as SP (site preference of <sup>15</sup>N) shows low values (10 to 12permil) that could be attributed to the production through of microbial nitrifier denitrification (reduction of nitrite to N<sub>2</sub>O mediated by ammonium oxidizers). The coincidence of this SP signal with high – stability layer, where sinking organic particles can accumulate, suggests that N<sub>2</sub>O could be produced by nitrifier denitrification inside particles. It is postulated that deceleration of particles in the pycnocline can modify the advection - diffusion balance inside particles, allowing the accumulation of nitrite and O<sub>2</sub> depletion suitable for nitrifier denitrication. As lateral advection seems to be relatively insignificant in the gyre, in situ nitrifier denitrification could account for 40–50% of the N<sub>2</sub>O produced in this layer. In contrast, coastal upwelling system is characterized by O<sub>2</sub> deficient condition and some N deficit in a eutrophic system. Here, N<sub>2</sub>O accumulates up to 480% saturation, and isotopic and isotopomer signals show highly complex N<sub>2</sub>O production processes, which presumably reflect both the effect of nitrification and denitrification at low O<sub>2</sub> levels on N<sub>2</sub>O production, but net N<sub>2</sub>O consumption by denitrification was not observed

Study of Ironless Permanent Magnet Devices Being Both a Coupling and an Axial Bearing for Naval Propulsion

This paper describes the study of an original permanent magnet device. This device works as both a coupling and as axial bearing. It can be particularly useful in naval propulsion application to transmit the torque without any contact between a motor axis and the propeller and to maintain the propeller in its axial position, compensating the axial force related to thrust. Two kinds of devices are studied for this type of specification. The first corresponds to the classical structure of cylindrical air-gap coupling. The second is an original structure where pairs of rings of axially magnetized magnets are stacked on each rotor. The computation of the behavior of the device (torque and axial force) is done using a semi-analytical method based on magnetic charge theory. This method allows a very fast calculation of the performances of the devices. This study shows the interest of the stacked structure this type of application

Human Frontal–Subcortical Circuit and Asymmetric Belief Updating

How humans integrate information to form beliefs about reality is a question that has engaged scientists for centuries, yet the biological system supporting this process is not well understood. One of the most salient attributes of information is valence. Whether a piece of news is good or bad is critical in determining whether it will alter our beliefs. Here, we reveal a frontal–subcortical circuit in the left hemisphere that is simultaneously associated with enhanced integration of favorable information into beliefs and impaired integration of unfavorable information. Specifically, for favorable information, stronger white matter connectivity within this system, particularly between the left inferior frontal gyrus (IFG) and left subcortical regions (including the amygdala, hippocampus, thalamus, putamen, and pallidum), as well as insular cortex, is associated with greater change in belief. However, for unfavorable information, stronger connectivity within this system, particularly between the left IFG and left pallidum, putamen, and insular cortex, is associated with reduced change in beliefs. These novel results are consistent with models suggesting that partially separable processes govern learning from favorable and unfavorable information

Semi-analytical study of 3 kinds of axial flux PM actuator

This paper deals with the study of discoidal Permanent Magnet machines using a method of field calculation based on the magnetic charges theory. This fast calculation method enables a systematic study of these devices. The presented method has been validated by a comparison with the classical FE method. Three kinds of discoidal machines are studied and compared. The first is a classical machine with axially magnetized magnets with iron stator and rotor cores. The second and third use simple Halbach array configurations for the magnets with iron and ironless rotor core. This study illustrates the interest of the Halbach structures for this type of device

Decay resistance against Coriolus versicolor in Sessile oak ( Quercus petraea Liebl.): analysis of the between-tree variability and correlations with extractives, tree growth and other basic wood properties

Abstract : Weight loss due to fungus Coriolus versicolor has been measured on 614 samples according to the NF EN 113 norm. Up to eight samples were cut at breast height (two opposite radii×four radial positions in heartwood) from 82 mature sessile oaks ( Quercus petraea Liebl.) originating from contrasting regions, silvicultural schedules and site qualities in France. The following points are addressed in the paper: (i) contribution to the total variability for weight loss of the effects "tree”, "position in the tree”, as well as their interaction; (ii) percentage of wood samples and trees in each of the five classes of natural durability defined by the norm NF EN 350-2; (iii) test of the effects of region, silvicultural schedule and site quality on weight loss and evaluating their contribution to the total variation; and (iv) correlations at tree level between weight loss and several traits related to tree growth and basic wood properties (density, swelling, grain angle, multiseriate wood rays characteristics, extractives content). The results are discussed with a view to aid the forest manager as well as the log/wood user to take advantage of the high level of between-tree variability observed as natural durability against C. versicolo

Parental Mentalizing during Middle Childhood: How Is the Adoption of a Reflective Stance Associated with Child’s Psychological Outcomes?

This exploratory cross-sectional study attempts to understand the mechanisms underlying the role of parental mentalizing in a child’s psychological functioning during middle childhood by using Parental Reflective Functioning (PRF) and Parental Insightfulness (PI) constructs. The main aims are to examine the role of PI and PRF as processes capable of influencing a child’s psychological functioning in terms of emotional–behavioral difficulties and social–emotional competencies. Eighty-six community parents (48 mothers, 38 fathers) and their 50 children in middle childhood (Mage = 10.10, SD = 1.13) participated in this study, recruited through a non-probabilistic sampling. The following measures were used to assess the aims of this study: Insightfulness Assessment, Parental Reflective Functioning Questionnaire, Child Behavior Check-list (CBCL) and Devereux Student Strengths Assessment (DESSA) questionnaires. Results showed that parental mentalizing was found to be significantly associated with both child’s internalizing and externalizing symptoms and social–emotional competencies as reported by parents through the CBCL and DESSA questionnaires. This study may offer a contribution to the study of parental mentalizing during middle childhood, supporting the hypothesis that both parents’ ability to understand their child’s mental states could affect the child’s psychological functioning. Clinical and theoretical implications are geared toward a family-based view with a specific focus on the importance of fostering in both parents a positive attitude toward mentalizing processes

Oakscan: procédé de mesure rapide et non destructif des polyphénols du bois de chêne de tonnellerie

Les polyphénols extractibles contenus dans le bois de chêne des barriques de tonnellerie sont des composés très importants car ils ont une influence sur la couleur et sur les propriétés organoleptiques des vins qu'ils enrichissent. Les analyses chimiques de laboratoire qui permettent de les mesurer sont réalisées sur des extractions, nécessitent un délai de réalisation très long et ne permettent d'analyser que des lots de matière par échantillonnage. Le procédé de mesure rapide et non destructif Oakscan® a été développé par la tonnellerie Radoux. Il se fonde sur la spectrométrie proche infrarouge et permet de mesurer la teneur en polyphénols en quelques secondes, directement sur le bois massif. Le contenu polyphénolique de chaque douelle est alors mesuré, permettant une meilleure maitrise de la matière première entrant dans la composition des fûts