Low doses of ionizing radiation induce immune-stimulatory responses in isolated human primary monocytes

The health effects arising from exposure to low doses of ionizing radiation are of particular concern, mainly due to the increased application of diagnostic and therapeutic X-ray modalities. The mechanisms behind the cell and tissue responses to low doses remain to be elucidated. Accumulating evidence suggests that low doses of ionizing radiation induce activation of the immune response; however, the processes involved have yet to be adequately investigated. Monocytes are key players in the induction of an immune response. Within the context of this study, we investigated the activation of toll-like receptors (TLRs), mitogen-activated protein kinases (MAPKs) and NF-B signaling in isolated human primary monocytes in response to low doses (0.05 and 0.1 Gy) and a high dose (1 Gy) of ionizing radiation. Using quantitative RT-PCR and ELISA techniques, our results showed a positive regulation of TLR signaling in response to low doses but a less significant response at high doses. This activation was demonstrated via the activation of TLR signaling molecules (HMGB1, TLR4, TLR9, MyD88 and IRAK1). Furthermore, and in contrast to the high dose, the low doses showed increased phosphorylation levels of the protein IB, and therefore positive signaling of the NF-B pathway. This result denotes pro-survival and pro-inflammatory responses. Additionally, MAPKs were activated in response to 0.05 Gy, while 0.1 and 1 Gy showed a downregulatory trend that may be related to activation of the PF4 gene. On the other hand, there was highly significant involvement of activated p53 and damaged genes in response to high but not low doses. In conclusion, this study addressed the need to re-evaluate health risks arising from exposure to low doses of ionizing radiation, particularly in view of the accumulating evidence reporting inflammatory and oncogenic consequences from these exposures

PLACE DU CAFE DANS LES SYSTEMES DE PRODUCTION DU SUD-OUEST ETHIOPIEN ET IMPACT PREVISIONNEL DES OUTILS DE CERTIFICATION

N° ISBN - 978-2-7380-1284-5International audienceThe role of coffee in southwest Ethiopia's production systems and the forecasted impact of certification projects. Southwest Ethiopia, the genetic cradle of Arabica coffee, is characterized by the progressive transformation of its forests, based on an enrichment of the last on coffee plants and on a lightening and speciesbased modification of the tree strata. The gathering and/or production of coffee, which is almost always combined with cereal cultivation with yoke in open fields and hand tool-based gardening in houses nearby within the very complex local production systems, is nowadays promoted as “forest coffee” or “wild coffee”, appellations that are nowadays used in some certification projects. Also, as a part of the current policies of development of this original product and protection of the forested areas, government allocates big forestry concessions to national and foreign investors. The aim of this communication is to analyse the role of coffee within the diversified production systems of southwest Ethiopia, and the possible effects of “forest coffee” certification projects on farmers' practices, income and socioeconomic differentiation evolution. Forestry concessions evolving into more and more of a capitalistic farming model – based on employment of precarious daily workers – this research work also poses the problem of the absence of fairness in this type of development. It also underlines the risks of the certification process cited above, which includes in the same chain value very different ways of producing coffee – both in terms of the production process and the associated social and production relations – and, in that sense, could create some confusion and, at the same time, could deprive the Ethiopian peasantry of a part of its patrimony

Novel synthesis of substituted 2-trifluoromethyl and 2-perfluoroalkyl N-arylpyridinium compounds – mechanistic insights

International audienceWe report a new one-pot synthesis of 2-trifluoromethylated/2-perfluoroalkylated N-aryl-substituted pyridiniums, 5,6,7,8-tetrahydroquinoliniums and 6,7,8,9-tetrahydro-5Hcyclohepta[b]-pyridinium compounds starting from an activated β-dicarbonyl analogue (here a perfluoro-alkylated gem-iodoacetoxy derivative), an aromatic amine and a (cyclic or acyclic) ketone. The key step of this multicomponent reaction, involves the formation of a 3-perfluoroalkyl- N,N’-diaryl-1,5-diazapentadiene intermediate, various examples of which were isolated and characterized for the first time, together with investigation of their reactivity. We propose a mechanism involving a concurrent inverse electron demand Diels-Alder or Aza-Robinson cascade cyclisation, followed by a bis-de-anilino-elimination. Noteworthy, a meta-methoxy substituent on the aniline directs the reaction towards a 2-perfluoroalkyl-7-methoxyquinoline, resulting from the direct cyclization of the diazapentadiene intermediate, instead of pyridinium formation. This is the first evidence of synthesis of pyridinium derivatives from activated β-dicarbonyls, ketones, and an aromatic amine, the structures of which (both reactants and products) being analogous to species involved in biological systems, especially upon neurodegenerative diseases such as Parkinson’s. Beyond suggesting chemical/biochemical analogies, we thus hope to outline new research directions for understanding the mechanism of in vivo formation of pyridiniums, hence possible pharmaceutical strategies to better monitor, control or prevent it

Analytical Model of Cage Induction Machine Dedicated to the Study of the Inner Race Bearing Fault

This paper presents a new analytical model for inner bearing raceway defect. The model is based on the presentation of different machine inductances as Fourier series without any kind of reference frame transformation. The proposed approach shows that this model is able to give important features on the state of the motor. Simulation based on spectral analysis of stator current signal using Fast Fourier Transform (FFT) and experimental results are given to shed light on the usefulness of the proposed model

Land erosion and associated evolution of clay minerals assemblages in Mediterranean region (Southern Turkey): Amik Lake

Under Mediterranean context, continuous human occupation is attested in the Amik Basin (southern Turkey) since 6000-7000 BC. The Basin also is crossed by The Dead Sea Fault (DSF), a major neotectonic structure in the Middle East extending from the Red Sea in the south to the East Anatolian Fault Zone in the north. The study focuses on the mineralogy and clay mineralogy record of the Amik Lake occupying the central part of the Basin. Our objective is to constrain major mineralogical and clay minerals evolution in the area over the last 4000 years and assess changes that would be related to the different land uses during the different Bronze, Roman, Ottoman and Modern civilizations. Sediments were collected at 1 to 2 cm intervals in core sediments up to a depth of 6 meters in the clay deposits. Geochemistry (XRF), mineralogy (XRD) and clay mineralogy are applied to study the sediment records. The age of the record is constrained combining radionuclide and radiocarbon dating. Chemical and mineralogical composition of sediments is quite diversified reflecting the significant geological variation of drainage basins. Abundant mixed-layer and partly disordered minerals characterize the different sedimentary levels recorded in those cores. Levels relatively rich in chlorite, illite and quartz are interpreted as corresponding to relatively dry periods, while more humid periods lead to more intensive weathering and consequently to the dominance of clay minerals more advanced in the relative stability scale, such as kaolinite. Smectite is taken to indicate a climate with contrasting seasons and a pronounced dry season. The sedimentary record clearly shows two periods indicating strong soil erosion in the Lake catchment. The most recent erosion phase is modern. The oldest one would have started during the late Bronze period and lasted until the late Roman Period. The first and older period is attributed to a strong aggradation linked to major increase in erosion. Our study shows that this episode has specific characteristics: mixed-layer clay mineral, high percent in Ni, Cr and Mg coupled with significant amount of organic matter of terrestrial origin. Ni and Mg most probably come from the Amanos Mountains an ophiolitic belt indicating an intensive upland cultivation and possible exploitation of its mineral resource. The second period is attributed to the modern period. The signature of the increase in erosion is different, because most of the soil cover has already been eroded. Only a patchy thin and unmature soil cover exists since the Late Roman time. Erosion is associated with a marked increase of smectite-illite interstratified clay, goethite and hematite found in deep soil horizons. Moreover, a marked increase in Cr is showed and is probably related to an enhanced exploitation of its mineral resource and to a renew land exploitation of the Amanos Mountain Range

Community management of deep boreholes

Community management of deep borehole

Optimal Observability-based Modelling, Design and Characterization of Piezoelectric Microactuators.

International audienceThis paper deals with the optimal design of monolithic piezoelectric microactuators with integrated proprioceptive sensors. Dedicated to the microrobotic and micromechatronic fields, these works detail the modelling and the characterization of compliant structures with integrated actuating and sensing elements. The proposed optimal design procedure adresses not only static criteria but also dynamic ones. This leads to microdevices which are more performant with regards to mechanical (displacement, force...) and control (dynamics, stability, precision) characteristics. Efficient design of such devices is achieved using a flexible building block method. A topological optimization method combined with an evolutionary algorithm is used to optimize the design of truss-like planar structure. This method chooses the best location among the different piezoelectric elements. Different mechanical, actuation or sensing elements are accordingly chosen from a data bank. From the control point of view, optimisation criteria are considered to enforce the observability of the vibrational dominant modes of the structure. Therefore, control and observation Gramians are exploited in the optimal design to shape the open loop frequency response of both, actuation and sensing functions of the integrated device. In the last part of the paper, based on these results, the optimal design and manufacturing of an innovative piezoelectric flexible microgripper is proposed. The prototype is manufactured from a monolithic piezoelectric material (PIC 151). Its reduced size (15 mm x 18 mm) fits the requirement of both microrobotics and micromechatronics applications, which is suitable for micromanipulation tasks. The characterization and the performance of this integrated microactuator finally close the paper and the efficiency of the optimal design procedure for micromechatronics applications are shown