Methods and codes for reservoir–atmosphere C-14 age offset calculations

Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Quaternary Geochronology 29 (2015): 97-103, doi:10.1016/j.quageo.2015.05.023.Reservoir age 14C offsets are invaluable tracers for past changes in carbon cycle and oceanic circulation. Reconstruction of reservoir age offsets with time is also required for calibration purposes (reconstruction of atmospheric calibration curve, calibration of non-atmospheric radiocarbon ages). Thus, properly propagating the various uncertainties linked to reservoir age offset is important for proper interpretation. However, approaches for reservoir age offset calculation – especially when considering pairs of reservoir-derived 14C and calendar ages – are usually not detailed and inadequate for proper propagation of uncertainties. Here, the various ways to properly calculate reservoir age offsets are described with an emphasis on a new approach when considering pairs of 14C and calendar ages. This approach maps the calendar age distribution onto the 14C time scale prior to reservoir age offset calculation – the “uncalibration-convolution process”. R codes computing reservoir age offsets based on available data are presented. Finally, a case study focusing on the reconstruction of the speleothem-atmosphere 14C age offsets of speleothem 14C data used in the latest release of the atmospheric calibration curve is discussed.G.S. acknowledges the Postdoctoral Scholar Program at the Woods Hole Oceanographic Institution (WHOI), with funding provided by the National Ocean Sciences Accelerator Mass Spectrometry Facility (NOSAMS)

Discovering Knowledge from Local Patterns with Global Constraints

It is well known that local patterns are at the core of a lot of knowledge which may be discovered from data. Nevertheless, use of local patterns is limited by their huge number and computational costs. Several approaches (e.g., condensed representations, pattern set discovery) aim at grouping or synthesizing local patterns to provide a global view of the data. A global pattern is a pattern which is a set or a synthesis of local patterns coming from the data. In this paper, we propose the idea of global constraints to write queries addressing global patterns. A key point is the ability to bias the designing of global patterns according to the expectation of the user. For instance, a global pattern can be oriented towards the search of exceptions or a clustering. It requires to write queries taking into account such biases. Open issues are to design a generic framework to express powerful global constraints and solvers to mine them. We think that global constraints are a promising way to discover relevant global patterns

Polyamines play a critical role in the control of the innate immune response in the mouse central nervous system

The present work investigated whether polyamines play a role in the control of the innate immune response in the brain. The first evidence that these molecules may be involved in such a process was based on the robust increase in the expression of the first and rate-limiting enzyme of biosynthesis of polyamines during immune stimuli. Indeed, systemic lipopolysaccharide (LPS) administration increased ornithine decarboxylase (ODC) mRNA and protein within neurons and microglia across the mouse central nervous system (CNS). This treatment was also associated with a robust and transient transcriptional activation of genes encoding pro-inflammatory cytokines and toll-like receptor 2 (TLR2) in microglial cells. The endotoxin increased the cerebral activity of ODC, which was abolished by a suicide inhibitor of ODC. The decrease in putrescine levels largely prevented the ability of LPS to trigger tumor necrosis factor α and TLR2 gene transcription in the mouse brain. In contrast, expression of both transcripts was clearly exacerbated in response to intracerebral spermine infusion. Finally, inhibition of polyamine synthesis abolished neurodegeneration and increased the survival rate of mice exposed to a model of severe innate immune reaction in the CNS. Thus, polyamines have a major impact on the neuronal integrity and cerebral homeostasis during immune insults

Local marine reservoir age (δr) reconstructed based on the tsunami deposit from Pangani bay (Tanzania)

Quantifying the local marine reservoir age (ΔR) and its change over time is critical for precise radiocarbon calibration of marine samples and for the study of the ocean carbon cycle. ΔR values are scarce for the African coast facing the Indian Ocean, and the few values available were obtained from pre-bomb shells collected during the 19th century. Here, the ΔR value for calibrated year 1110 ± 25 (1σ) CE was reconstructed from radiocarbon dating and Bayesian analysis of marine and terrestrial materials coexisting in a tsunami deposit discovered in Pangani Bay (Tanzania, western Indian Ocean coast). The reconstructed ΔR of –8 ± 40 (1σ, n = 3) is similar to pre-bomb regional estimates and provides new information to investigate regional ΔR change over time. The Bayesian analysis of the dated samples revises the age of the tsunami event found in Pangani Bay to 1064–1157 cal CE (95.4% confidence level) or 1110 ± 25 (1σ) cal CE, about one century younger compared to the previous estimate. Our results indicate that the new ΔR value and the proposed calibration approach can be used to refine existing chronologies in the region, with implications for paleo-environmental reconstructions and archaeological studies of Early Swahili societies

Rol de la lengua en el curso de las funciones orofaciales

La mayor parta de las funciones de la zona orofacial requieren la actividad lingual, ya sea para asegurar la supervivencia o para establecer un contacto con el mundo exterior. La lengua participa permanentemente en el equilibrio neuromuscular de esta región. Si hay equilibrio entre los diferentes grupos musculares en el transcurso del crecimiento, el desarrollo será armonioso, en cambio todo desequilibrio repercutirá sobre la morfogénesis. Si e¡ equilibrio no es restablecido, los componentes perturbados continúan a lo largo de toda la vida, induciendo diversas patologías del sistema estomatognático (desplazamientos dentarios, síndrome algio-disfuncional, etc.). En particular el comportamiento lingual juega un rol determinante sobre la posición de los dientes. Es por consiguiente, tratando de no perder de vista esta relación de causa y efecto entre comportamientos y dismorfosis, que el autor propone un estudio de las diferentes funciones orofaciales y de la participación lingual en esas funciones. Un mejor conocimiento de la fisiología y de la patología de la funcionalidad que de ello resultan, debería permitir la mejor comprensión y el mejor tratamiento de las dismorfosis

Fouille de règles d'annotation pour la reconnaissance d'entités nommées

National audienceComme pour de nombreuses autres problématiques TAL, la reconnaissance d'entités nommées met en jeu aussi bien des systèmes à base de connaissances que des systèmes guidés par les données. Dans cet article, nous proposons une approche médiane par l'adaptation de méthodes issues de l'extraction de connaissances. Notre système, mXS, intègre des techniques de fouille séquentielle hiérarchique pour la détection des entités nommées. Le système adopte une démarche centrée sur les données pour extraire des motifs symboliques. Il repose par ailleurs sur une stratégie originale qui consiste à rechercher séparément le début et la fin des entités. Cette approche présente l'intérêt de conserver une certaine robustesse par rapport aux bruit et disfluences. Elle est adaptée au cadre applicatif visé par le système : la détection d'entités nommées au sein de flux de parole conversationnelle transcrite automatiquement. À ce titre, mXS a participé à la campagne d'évaluation ETAPE où il a présenté de bons résultats. Cet article présente le fonctionnement de mXS et ses performances sur les jeux de données issus de deux campagnes d'évaluation francophones (ESTER 2 et ETAPE)

Les mesures de ré-insertion sociale: Des programmes d'entretien invitant à redéfinir l'intervention sociale?

Enlighten by welfare policy analysis, this paper critic and suggests some questions about social reintegration. Starting with long-term social programs as a problem to presuppose, the author explains four tenets according to which social measures usually take place. To conclude, a corpus of new issues are presented in order to update what the author tries to argue in social reintegration programs.Partindo da análise política das questões sociais, o autor questiona os problemas e as modalidades dos programas de reinserção social. Apresenta quatro princípios de acção dos programas de reintegração social e questiona os efeitos da manutenção prolongada dos/nos programas de (re)integração social. Por fim, propõe uma série de novas questões acerca da necessidade de redefinição da intervenção social