184 research outputs found
Maisons et agglomérations à l'âge du bronze en Syrie du Sud
A paraître dans : HAURAN V - Déterminismes géographiques et communautés humaines en Syrie du Sud du néolithique à l'antiquité tardive. Recherches récentesSous la direction deMichel al-Maqdissi, Frank Braemer, Jean-Marie Dentzer BAH ; IFPO BeyrouthEn Syrie du Sud la remarquable conservation des vestiges et leur bonne lisibilité en surface ont permis de localiser et de relever des agglomérations, parfois sur d'importantes superficies. Les fouilles et prospections ont permis le relevé d'une cinquantaine de plans de sites datés entre le 4e et le 2e millénaire. Cette région est en effet un véritable conservatoire, sans doute unique au monde, de structures architecturales protohistoriques.Cet article se limite à une description générale des formes d'habitat domestique et de l'organisation des agglomérations, et n'aborde donc pas les questions des aménagements des paysages autour des sites (principalement les ouvrages hydrauliques), des édifices monumentaux et des techniques de fortification. Ces régions étaient occupées principalement par des populations pastorales mobiles qui ont bien souvent construit des agglomérations fixes qui représentent les points d'appui logistique (réserves, assemblées, etc..) de leur circuit de déplacement cyclique
Proactive Inhibitory Control of Response as the Default State of Executive Control
Refraining from reacting does not only involve reactive inhibitory mechanisms. It was recently found that inhibitory control also relies strongly on proactive mechanisms. However, since most available studies have focused on reactive stopping, little is known about how proactive inhibition of response is implemented. Two behavioral experiments were conducted to identify the temporal dynamics of this executive function. They manipulated respectively the time during which inhibitory control must be sustained until a stimulus occurs, and the time limit allowed to set up inhibition before a stimulus occurs. The results show that inhibitory control is not set up after but before instruction, and is not transient and sporadic but sustained across time. Consistent with our previous neuroimaging findings, these results suggest that proactive inhibition of response is the default mode of executive control. This implies that top-down control of sensorimotor reactivity would consist of a temporary release (up to several seconds), when appropriate (when the environment becomes predictable), of the default locking state. This conclusion is discussed with regard to current anatomo-functional models of inhibitory control, and to methodological features of studies of attention and sensorimotor control
Functional connectivity changes associated with fMRI neurofeedback of right inferior frontal cortex in adolescents with ADHD
Attention Deficit Hyperactivity Disorder (ADHD) is associated with poor self-control, underpinned by inferior fronto-striatal deficits. We showed previously that 18 ADHD adolescents over 11 runs of 8.5 min of real-time functional magnetic resonance neurofeedback of the right inferior frontal cortex (rIFC) progressively increased activation in 2 regions of the rIFC which was associated with clinical symptom improvement. In this study, we used functional connectivity analyses to investigate whether fMRI-Neurofeedback of rIFC resulted in dynamic functional connectivity changes in underlying neural networks. Whole-brain seed-based functional connectivity analyses were conducted using the two clusters showing progressively increased activation in rIFC as seed regions to test for changes in functional connectivity before and after 11 fMRI-Neurofeedback runs. Furthermore, we tested whether the resulting functional connectivity changes were associated with clinical symptom improvements and whether they were specific to fMRI-Neurofeedback of rIFC when compared to a control group who had to self-regulate another region. rIFC showed increased positive functional connectivity after relative to before fMRI-Neurofeedback with dorsal caudate and anterior cingulate and increased negative functional connectivity with regions of the default mode network (DMN) such as posterior cingulate and precuneus. Furthermore, the functional connectivity changes were correlated with clinical improvements and the functional connectivity and correlation findings were specific to the rIFC-Neurofeedback group. The findings show for the first time that fMRI-Neurofeedback of a typically dysfunctional frontal region in ADHD adolescents leads to strengthening within fronto-cingulo-striatal networks and to weakening of functional connectivity with posterior DMN regions and that this may be underlying clinical improvement
The New CEN/TS 19100: Design of Glass Structures
Since the beginning of 2021, CEN/TS 19100 Design of Glass Structures has been available in its first three parts. The fourth part is expected soon. This Technical Specification of the European standards organisation CEN is as a pre-standard of a corresponding future Eurocode. These documents constitute the first ever comprehensive design code for the entire structural glass engineering field on the European market for the first time. In addition to a clear outline, the Technical Specification has been drafted to be compatible with EN 1990 “Basis of Design” and to address glass-specific design matters, particularly related to robustness and redundancy. Although the standard still has the status of a CEN/TS, thereby allowing the European nations the option of whether to introduce it, either in full or in parts, it already contains national openings through which the European countries can adapt the design results to their own safety level by National Determined Parameters (NDPs). Such an approach already anticipates the future Eurocode, which is expected to be published as EN 19100—Design of Glass Structures. This article provides some context on the history and concept behind the new documents and gives an overview of the design rules and the corresponding technical background of the different parts of CEN/TS 19100
Rewards that are near increase impulsive action
International audienceIn modern society, the natural drive to behave impulsively in order to obtain rewards must often be curbed. A continued failure to do so is associated with a range of outcomes including drug abuse, pathological gambling, and obesity. Here, we used virtual reality technology to investigate whether spatial proximity to rewards has the power to exacerbate the drive to behave impulsively toward them. We embedded two behavioral tasks measuring distinct forms of impulsive behavior, impulsive action, and impulsive choice, within an environment rendered in virtual reality. Participants responded to three-dimensional cues representing food rewards located in either near or far space. Bayesian analyses revealed that participants were significantly less able to stop motor actions when rewarding cues were near compared with when they were far. Since factors normally associated with proximity were controlled for, these results suggest that proximity plays a distinctive role in driving impulsive actions for reward
Qarassa, un site du Bronze ancien et moyen en Syrie du Sud
A la suite d’une prospection régionale du plateau basaltique du Leja, le site de Qarassa a été choisi pour la fouille en raison de sa représentativité chronologique du Natoufien à l’âge du Fer qui en fait la première référence chronostratigraphique longue pour la zone basaltique. Le tell sud de Qarassa est occupé du milieu du IVe jusqu’au deuxième quart du Ier millénaire. On propose ici une synthèse des résultats de la fouille des niveaux du Bronze ancien de cette agglomération fortifiée.Following the regional survey of the Leja’s basaltic plateau, the excavation of Qarassa was decided because this site occupied from the Natufian to the Iron Age becomes a major chrono-stratigraphic reference for the basaltic area of southern Syria. The southern tell at Qarassa is occupied from the mid 4th to the second quarter of the 1st mill. We give here a first synthesis of the excavation’s results about the Early Bronze Age fortified agglomeration.خلاصة – اثر عملية مسح الإفريز البازلتي في لجا وقع الإختيار على موقع القراصة لإجراء الحفريات بسبب تمثليته الزمنية للفترة الناتوفية خلال العصر الحديدي والتي تجعل منها أول مرجع زمني وطبقي للمنطقة البزلتية إن التل الجنوبي للقراصة مسكون منذ أواسط القرن القرن الرابع إلى الربع الثاني من الألفية الأولى ونقترح هنا تأليفا لنتائج الحفريات على مستوى العصر النحاسي لهذه المناطق السكنية المحصنة
A Raman spectroscopic study of arsenite and thioarsenite species in aqueous solution at 25°C
The Raman spectra of thioarsenite and arsenite species in aqueous solution were obtained at room temperature. Solutions at constant ΣAs + ΣS of 0.1 and 0.5 mol kg(-1 )were prepared with various ΣS/ΣAs ratios (0.1–9.0) and pH values (~7–13.2). Our data suggest that the speciation of As under the conditions investigated is more complicated than previously thought. The Raman measurements offer evidence for at least six separate S-bearing As species whose principal bands are centered near 365, 385, 390, 400, 415 and 420 cm(-1). The data suggest that at least two different species may give rise to bands at 385 cm(-1), bringing the probable minimum number of species to seven. Several additional species are possible but could not be resolved definitively. In general, the relative proportions of these species are dependent on total As concentration, ΣS/ΣAs ratio and pH. At very low ΣS/ΣAs ratios we also observe Raman bands attributable to the dissociation products of H(3)AsO(3)(aq). Although we were unable to assign precise stoichiometries for the various thioarsenite species, we were able to map out general pH and ΣS/ΣAs conditions under which the various thioarsenite and arsenite species are predominant. This study provides a basis for more detailed Raman spectroscopic and other types of investigations of the nature of thioarsenite species
Linking cognitive measures of response inhibition and reward sensitivity to trait impulsivity
Impulsivity is regarded as a multifaceted construct that comprises two dimensions: rapid-response impulsivity and reward-delay impulsivity. It is unclear, however, which aspects of trait impulsivity, as assessed by self-report measures are related to rapid-response impulsivity and/or to reward-delay impulsivity, as different results have been reported in studies using both self-report and cognitive measures. This study aimed to directly relate self-report measures of impulsivity to cognitive measures of impulsivity in individuals at low- or high-levels on two impulsivity dimensions, specifically rapid-response impulsivity and reward-delay impulsivity. Participants were classified into high- or low-impulsivity groups based on (1) level of rapid-response impulsivity (determined by BIS-11 Motor subscale scores); (2) level of reward-delay impulsivity (determined by BIS/BAS subscale scores); and (3) a combination of rapid-response impulsivity and reward-delay impulsivity levels. Impulsivity was assessed using Go/No-Go, Stop-Signal and Delay-Discounting tasks and self-report measures. The high rapid-response impulsivity group showed significantly higher reward-delay impulsivity on both, the Delay-Discounting tasks and on self-report measures assessing reward-delay impulsivity, than the low-risk group. Based on the level of reward-delay impulsivity, the high reward-delay impulsivity group scored significantly higher on task-based (cognitive) and self-report measures assessing rapid-response inhibition than the low reward-delay impulsivity group. Combining both dimensions of impulsivity showed that the high-impulsivity group performed significantly worse in rapid-response paradigms and temporally discounted significantly more impulsively than the low-impulsivity group. Thus, combined impulsivity factors provide better assessment of impulsivity than each dimension alone. In conclusion, robust differences in impulsivity can be identified in non-clinical young adults
Neuroimaging the consciousness of self: Review, and conceptual-methodological framework
We review neuroimaging research investigating self-referential processing (SRP), that is, how we respond to stimuli that reference ourselves, prefaced by a lexical-thematic analysis of words indicative of “self-feelings”. We consider SRP as occurring verbally (V-SRP) and non-verbally (NV-SRP), both in the controlled, “top-down” form of introspective and interoceptive tasks, respectively, as well as in the “bottom-up” spontaneous or automatic form of “mind wandering” and “body wandering” that occurs during resting state. Our review leads us to outline a conceptual and methodological framework for future SRP research that we briefly apply toward understanding certain psychological and neurological disorders symptomatically associated with abnormal SRP. Our discussion is partly guided by William James’ original writings on the consciousness of self
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