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International audience; In the field of clustering techniques, little attention has been paid to the recovery of a set of clusters from the structure of an additive tree. To bridge this gap, this work presents an original partitioning technique which aims to reveal clusters from an additive tree that represents a large set of objects. Specifically, an algorithm that splits a tree into successive subtrees was developed, based on a ratio of the lengths of edges. The stability of the clusters obtained with this technique was then evaluated using measurements of cohesion and isolation that were generated using a bootstrapping strategy. Finally, the degree of association of each object to clusters was analyzed to gain insight into their internal structure. This analysis was performed on the results of a sorting task conducted by 156 subjects, who were asked to sort 96 terms associated with the odor of wine. The methodology developed in this paper represents an innovative way to highlight groups of terms within a large set of wine odor attributes, with the ultimate goal being to improve the structure of the lexicon.

International audience; Aromatic characterization is a key element of enhancing one's knowledge of wine. While several studies have investigated the importance of wine expertise in the ability to perform odor-related sensory tasks, little attention has been paid to the influence of expertise on the semantic categorization of wine odors. To bridge this gap, this study aimed to explore the influence of a subject's expertise on the semantic representation of wine odors by means of a free sorting task. For this purpose, 156 subjects were recruited. Their level of expertise was measured using a questionnaire and the data analysis revealed four clusters of subjects with a gradual level of expertise. Subjects also performed a sorting task on 96 odor terms. From the number and the size of odor groups formed, as well as the additive tree representation and the consensus partition between the terms for each expertise level, we observed that all subjects, regardless of their experience, had largely the same semantic categorization of wine-odor attributes, which was mainly shaped by the sources of the odorants. It appeared that level of wine expertise played a minor role in creating the semantic representation of wine odors, affecting mainly the knowledge of specialized terms.

Esophageal atresia (EA) is prenatally diagnosed in less than one third of the cases and is usually only suspected. Recently, magnetic resonance imaging (MRI) with dynamic sequence and biochemistry of the amniotic fluid have been proposed to enhance prenatal diagnosis of EA. We report the case of a triple negative screening (ultrasound, MRI with dynamic sequence and biochemistry of the amniotic fluid) with a postnatal diagnosis of EA type III with a small defect. Even using second line tests, prenatal diagnosis of EA remains a challenge.

The concept of terroir is widely used in the wine industry, and many studies are undertaken to better understand the influence of local terrain features on produced wines. In this context, this study monitored nine Chardonnay plots in the Fruili wine region of Italy to gather information on grapevine growth and berry ripening. The study objective was to define viticulture potentialities allowing to identify future strategies for the production of a “single vineyard” Chardonnay wine at the Vie di Romans estate, Italy. During the growing season of 2017, relations were studied between terrain features and field observations on vine phenology and grape ripening. Stem water potential and gas exchange measurements were also effectuated. Results show that there are significant differences between the studied plots. Earliness of the grapevine cycle between the plots has been less evident to determine than the variation in berry characteristics. The latter were linked with identified pedoclimatic units, but the effect of the cultural practices should not be overlooked. The study should be perceived as a first monitoring campaign, highlighting the important differences between study plots. Further investigation in the following seasons should give a more accurate perception of individual plot characteristics and their impacts.

The title compound is prepared by adding aqueous ammonia to a solution of phosphoric acid containing a small amount of iron (III) ions (3%). It crystallizes in the monoclinic system, space groupC2/c,a=16.8450(9) A,b=9.6111(1) A,c=17.6470(7) A, andβ=90.91(2)°,R=0.031, and wR=0.078. The structure consists of a two-dimensional framework made of HPO4, H2PO4groups, and FeO6octahedra sharing corners. In one layer, the NH+4cations are located inside 12 membered windows, which are generated by the corner-sharing FeO6and H2PO4. Water molecules lay in the interlayer space. With regard to magnetic properties, carried out in the range 1.7–300 K, the polycrystalline sample follows a Curie–Weiss law down to 30 K. At lower temperatures is a magnetic phase transition, where a spontaneous magnetization appears. This behavior suggests either a ferrimagnetic or a weak ferromagnetic order.

The Guerrero terrane in western Mexico consists of upper Jurassic‐lower Cretaceous volcano‐plutonic and volcano‐sedimentary arc sequences developed in an intra‐oceanic setting and accreted to North America late in the Early Cretaceous. The Playa Azul sequence belongs to the southern Pacific Province of the Guerrero terrane (PPGT), which extends along the Pacific coast from Puerto Vallarta to Acapulco. This sequence is composed of pyroclastic rocks and rare lava flows interlayered with red detrital rocks and coastal calcarenites. The red beds yielded Early Cretaceous dinosaur footprints. The whole sequence is capped by Albian to Cenomanian reefal limestones. The rare basalts are olivine‐phyric and include altered amphibole‐bearing cumulates. The most common facies are amphibole‐biotitephyric andesites and dacites. The welded, or not, tuffs have K‐feldspar, quartz, and plagioclase phenocrysts, while their groundmass includes biotite and zircon. Amphibole ranges in composition from pargasitic hornblende to e...

C. COULON*, P. VIDAL, C. DUPUY, P. BAUDIN, M. POPOFF*, H. MALUSKI AND D. HERMITTE 'PETROLOGIE MAGMATIQUE, URA 1277, CEREGE, BP 80, 15545 AIX EN PROVENCE CEDEX 4, FRANCE 'CENTRE DE RECHERCHES VOLCANOLOGIQUES, URA 10, 63038 CLERMONT FERRAND CEDEX, FRANCE 'CENTRE GEOLOGIO.UE ET GEOPHYSIO.UE, CNRS, PLACE BATAILLON, J4095 MONTPELLIER CEDEX, FRANCE *INSTITUT DE GEODYNAMIQ.UE, URA 1279, UNIVERSITE DE NICE—SOPHIA ANTIPOLIS, AVENUE EINSTEIN, 06560 VALBONNE, FRANCE LABORATOIRE DE GEOCHRONOLOGIE—GEOCHIMIE, URA 176J, PLACE BATAILLON, 34095 MONTPELLIER CEDEX, FRANCE

Background Several studies have suggested that the main features of preeclampsia (PE) are consequences of endothelial dysfunction related to excess circulating anti-angiogenic factors, most notably, soluble sVEGFR-1 (also known as sFlt-1) and soluble endoglin (sEng), as well as to decreased PlGF. Recently, soluble VEGF type 2 receptor (sVEGFR-2) has emerged as a crucial regulator of lymphangiogenesis. To date, however, there is a paucity of information on the changes of VEGFR-2 that occur during the clinical onset of PE. Therefore, the aim of our study was to characterize the plasma levels of VEGFR-2 in PE patients and to perform VEGFR-2 immunolocalization in placenta. Methodology/Principal findings By ELISA, we observed that the VEGFR-2 plasma levels were reduced during PE compared with normal gestational age matched pregnancies, whereas the VEGFR-1 and Eng plasma levels were increased. The dramatic drop in the VEGFR-1 levels shortly after delivery confirmed its placental origin. In contrast, the plasma levels of Eng and VEGFR-2 decreased only moderately during the early postpartum period. An RT-PCR analysis showed that the relative levels of VEGFR-1, sVEGFR-1 and Eng mRNA were increased in the placentas of women with severe PE. The relative levels of VEGFR-2 mRNA as well as expressing cells, were similar in both groups. We also made the novel finding that a recently described alternatively spliced VEGFR-2 mRNA variant was present at lower relative levels in the preeclamptic placentas. Conclusions/Significance Our results indicate that the plasma levels of anti-angiogenic factors, particularly VEGFR-1 and VEGFR-2, behave in different ways after delivery. The rapid decrease in plasma VEGFR-1 levels appears to be a consequence of the delivery of the placenta. The persistent circulating levels of VEGFR-2 suggest a maternal endothelial origin of this peptide. The decreased VEGFR-2 plasma levels in preeclamptic women may serve as a marker of endothelial dysfunction.

The Guerrero terrane (western Mexico) is composed of Late Jurassic – Early Cretaceous plutono-volcanic and volcano-sedimentary sequences of the Alisitos–Teloloapan arc that accreted to the North American craton at the end of the Early Cretaceous. The geodynamic evolution of the Guerrero terrane is that of the Alisitos–Teloloapan intraoceanic arc, partly built on continental crust and partly on oceanic crust. The growth of the arc was likely linked to the subduction of the Arperos and Olvidada basins fringing the North American borderland. The subduction was dipping west-south-west.The continent-based segment of the arc, which is presently exposed mainly in northwestern Mexico, is composed of aerial and submarine K-rich calc-alkaline basalts, andesites, and rhyolites and of siliceous pyroclastic rocks interbedded with Aptian–Albian bioclastic carbonates or red beds bearing dinosaurus foot prints. The calc-alkaline basalts and andesites show light rare earth elements enriched patterns and high concentrations in large ion lithophile elements. The siliceous andesites and rhyodacites display low contents in Y and heavy rare earth elements, uncommon for such calc-alkaline SiO2-saturated rocks. This depletion is likely linked to amphibole fractionation and to the presence of sphene and zircon, minerals known to concentrate the heavy rare earth elements.In contrast, the magmatic arc sequences built on oceanic crust, that crops out in central-southern areas of the Guerrero terrane, show an evolution with time. The activity of the arc began with depleted tholeiitic igneous rocks, followed first by mature tholeiitic basalts, then by calc-alkaline olivine basalts interbedded with micritic limestones and radiolarian oozes of Early Cretaceous age (Neocomian). At the end of the arc development, in Late Aptian–Albian, calc-alkaline pillow basalts and andesites erupted at the volcanic front whereas shoshonitic basalts emitted backwards. In the late Early Cretaceous, the arc drifted towards the north and collided with the craton. Arc tholeiites are characterized by flat rare earth element patterns or slightly depleted in light rare earth elements and by high εNd ratios. The calc-alkaline plutonic and volcanic rocks show light rare earth elements enriched patterns and their εNd ratios decrease with time. This decrease of the εNd ratios suggests that either the mantle source of the calc-alkaline rocks was contaminated by subducted terrigenous sediments derived from an old continental crust (North American craton) or that these calc-alkaline rocks derive from the partial melt of an oceanic island basalt source present in the mantle wedge. The shoshonitic features of the basalts are marked by the presence of sanidine in the groundmass and the high levels of K2O, Ba, and Sr of the unaltered rocks.

9 pages; International audience; For the first time, using an extrusion process, macroscopic composite poly-vinyl alcohol(PVA)/polyaniline (PANI)-V2O5 fibers have been generated. Besides the extrusion process itself, this is certainly the first redox reaction addressed while performing an extrusion shaping process. The as-synthesized fibers have been characterized at different length scales, revealing at the mesoscale a 30° preferential orientation of the nanoribbons subunits toward the macroscopic fiber main axis. At the microscopic length scale, despite a semiamorphous nature, electron spin resonance (ESR) spectroscopy has been employed to reveal partial reduction of V5+ species to V4+ ones, where the paramagnetic species local environment has been found to be close to hydrated vanadium oxide xerogels. Concerning the organic counterpart, the aniline is oxidized into poly aniline when considering both the fibers characterization through ESR and Fourier transformed infrared (FTIR) spectroscopy and the well-known strongly oxidizing character of V5+ species toward aniline. These new PVA/PANI-V2O5 fibers are cycling when sensing alcoholic vapors while offering a good selectivity. The addressed sensitivity allows sensing 5 ppm of ethanol within 3-5 s at 42 °C. Beyond, the as-synthesized PVA/PANI-V2O5 macroscopic fibers possess a toughness of 12 J g-1, a value that has been increased by more than 120 times when compared with nanoporous inorganic fibers.

Trophoblast invasion is a key process during human placentation. This event constitutes the basis of the conversion of the uterine spiral arteries, a process which allows an adequate vascular connection between the intervillous space and the maternal blood flow. Trophoblast invasion is transient, with stringent spatial and temporal control. Preeclampsia, a leading cause of maternal and fetal mortality and morbidity, is associated with decreased, shallow trophoblastic invasion. In this article, we review the molecular mechanisms of trophoblast invasion, and its mechanisms of regulation. Insights into the etiopathogenesis of preeclampsia will also be detailed.

In recent years, consumers have become more health conscious in their food choices but they also have less time to prepare healthy meals. As a result, minimally processed (MP) products have become an important sector of the food industry because of their ‘fresh-like’ qualities, convenience and speed of meal preparation. In this study, the physical qualities of MP potatoes (‘Desiree’ variety) stored for 7 days in vacuum packaging were evaluated. The shelf life of MP potatoes was effectively extended to nearly 1 week under refrigerated storage by using vacuum packaging systems. The main quality parameters were constant during storage.

Ca(2+) channels play a key role in the basic working of the heart. There is one particular type of Ca(2+) channel in cardiac cells (L-type) whose gating is affected in different ways by beta-adrenoceptors and 1,4-dihydropyridines. In this study, we used ex vivo studies and PET to evaluate and compare the myocardial kinetics of the enantiomers labeled with (11)C (the more active: S12968, absolute configuration S; the less active: S12967, absolute configuration R) of the L-type Ca(2+) channel antagonist S11568 (3-ethyl 5-methyl (+/-)-2-[(2-(2-aminoethoxy)ethoxy) methyl]-4-(2,3-dichlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate).[(11)C]S12968 was injected into the tail vein of rats (0.22 kBq--5.92 MBq) to assess the relationship between injected dose and myocardial uptake. A series of 5 rats was pretreated with 4 micromol unlabeled S12968 5 min before injection of 2.2 kBq [(11)C]S12968. In another series of 5 rats, unlabeled S12698 (4 micromol) was injected 5 min after injection of 2.2 kBq [(11)C]S12968. The animals were killed 15 min later, and the myocardial radioactivity was assessed in a gamma well counter. Beagle dogs received injections of 5-15 nmol [(11)C]S12968 or [(11)C]S12967 and were imaged with PET. Presaturation and displacement experiments using 2 micromol/kg unlabeled S12968 or 6 mol/kg S12967 were performed.In rats, a statistically significant relationship between myocardial uptake and injected dose of S12968 was observed. Pretreatment or displacement with unlabeled S12968 reduced myocardial radioactivity by 75% and 70%, respectively. In dogs, after injection of 5 nmol of each enantiomer, myocardial radioactivity plateaued within 3 min and the clearance from blood was rapid. Injection of 13--15 nmol [(11)C]S12968 led to a higher myocardial uptake and a more rapid washout, which were related to an increased coronary blood flow as shown by the linear relationship between k(1)--an estimate of coronary blood flow--and the mass of S12968 injected. Presaturation and displacement experiments showed that 70%--80% of S12968 binding was specific. This specificity was not observed with S12967. Plasma metabolite analysis showed that 70% of the compound was unchanged 20 min after injection.These results show the feasibility of imaging myocardial L-type Ca(2+) channels in vivo using [(11)C]S12968.

We report conductivity measurements on solutions of closed compact monodisperse multilamellar vesicles (the so-called "onion texture") formed by shearing an inverse lyotropic lamellar L(alpha) phase. The conductivity measured in different directions as a function of the applied shear rate reveals a small anisotropy of the onion structure due to the existence of free oriented membranes. The results are analyzed in terms of a simple model that allows one to deduce the conductivity tensor of the L(alpha) phase itself and the proportion of free oriented membranes. The variation of these two parameters is measured along a dilution line and discussed. The high value of the conductivity perpendicular to the layers with respect to that of solvent suggests the existence of a mechanism of ionic transport through the insulating solvent.

The magnetic properties of A 1 C 60 salts (A = Rb, Cs) are discussed comparing magnetization and electron paramagnetic resonance at different microwave frequencies We show that the low temperature ground state is not a conventional antiferromagnetic order. We rather observe two kinds of spins which experience different local fields.

Central nicotinic acetylcholine receptors (nAChRs) have been implicated in learning-memory processes. Postmortem brain tissue of patients who suffered senile dementia or Parkinson's disease shows low density of nAChRs. In this study, we used PET to evaluate the distribution and kinetics of the fluoro derivative of the high-affinity and alpha4beta2-subtype-selective, nicotinic ligand 3-[2(S)-2-azetidinylmethoxy]pyridine (A-85380) in baboons.After intravenous injection of 37 MBq (1 mCi, 1-1.5 nmol) [18F]fluoro-A-85380 into isoflurane-anesthetized baboons, dynamic PET data were acquired for 180 min. Time-activity curves were generated from regions of interest. Displacement experiments (80 min after injection of the radiotracer) were performed using cytisine (1 mg/kg subcutaneously) and unlabeled fluoro-A-85380 (0.1 and 0.3 mg/kg intravenously). Toxicological studies were performed in mice.Brain radioactivity reached a plateau within 40-50 min of injection of the tracer. In the thalamic area, radioactivity remained constant for 180 min, while clearance from the cerebellum was slow (t1/2 = 145-190 min). Cytisine and unlabeled fluoro-A-85380 reduced brain radioactivity at 180 min by 50%-60%, 30%-35% and 20%-35% of control values in the thalamus, cerebellum and frontal cortex, respectively. A slight, transient increase (20 mm Hg) in blood pressure was observed with the highest displacing dose of unlabeled fluoro-A-85380. Lethal dose in mice was found to be 2.2 mg/kg intravenously.These results demonstrate the feasibility and the safety of imaging nAChRs in vivo using labeled or unlabeled fluoro-A-85380.

International audience

During and mainly after the Tertiary continental collisions, regions of extension and subsidence developed within the Alpine-Mediterranean orogenic belt in the rear part of the contemporaneously active arcs. Mediterranean back-arc basins are characterized by a hot upper mantle, overlain by crust transitional from continental to oceanic, which reflects their different stages of maturation. The four basins considered here are, in order of increasing maturity, the Pannonian Basin, the Aegean Basin, the Alboransouth Balearic Basin and the Tyrrhenian Basin. Back-arc extension is not a rigid plate opening but rather an areal expansion associated with progressive bending of the arc. The most successful models suggested for the evolution of Mediterranean back-arc basins imply updoming of the asthenosphere accompanied by lithospheric attenuation, stretching and dyke intrusion. The force behind asthenospheric updoming is under debate; active and passive mechanisms have been suggested. It seems, however, certain that gravity plays an important role in initiating and maintaining back-arc extension. Basin subsidence is an isostatic response to structural changes of the lithosphere and to conductive decay of the associated heat anomaly. A quantitative model for basin formation can be obtained only if the subsidence history is well documented.

The 1981 French–Chinese expedition to Tibet focused on the Lhasa block, extending earlier coverage 400 km north of the Tsangpo suture. The Lhasa block stood between 10 and 15° N latitude over most of the Upper Cretaceous and Eocene and, if Gondwanian in origin, had detached from Gondwana by early Permian. Seismic profiles reveal a complex Moho topography resulting both from multiple continental thrusting and large-scale strike-slip faulting. Subduction related granitoids representing mixtures of mantle and crustal components and anatectic granitoids have been analysed and dated. This study emphasizes the role of smaller blocks in the accretion of the continental mosaic.

In calc-alkaline orogenic plutons, the dark xenoliths and their host rocks must be considered the expression of partial mixing of magma.Three associations of this type have been investigated and are illustrated by the Bono pluton (northern Sardinia)— a composite pluton including three intrusives of different nature (tonalitic to granodioritic) and containing a very large number of basaltic xenoliths of magmatic origin. Detailed mineralogical analysis of the two end members in each association, coupled with geochemical data, has determined the major petrogenetic mechanisms intervening in the mixing process in a plutonic setting: temperature equilibration, mechanical exchanges of crystals, chemical exchanges, etc. The most important result of this article, however, is to show that each intrusion is related to a specific group of xenoliths that is characterized by constant FeOt/MgO. The latter reflects the different composition of basaltic components, and it is concluded that each intrusive event is associated with a unique mixing episode. As in volcanic settings, the mixing process may have initiated the intrusion.The extreme compositional variations in the magmatic xenoliths, recognized in several series of orogenic plutons, is explained here by different initial basaltic end members and by variation in the intensity of the interaction mechanisms. [Journal Translation]

The study of the frustrated SA free energy allows the theoretical understanding of the recently discovered SA antiphase, as two dimensional escape to incommensurate phases. The picture obtained agrees with X-ray experimental evidence. We further give the phase diagram between bilayer SA', incommensurate S Ai , and antiphase SA.

The Early Devonian volcanic sequence of the eastern Klamath Mountains (northern California) consists of the Copley Greenstone, a basalt–andesite series, overlain by the Balaklala Rhyolite. All the rocks are metamorphosed to the greenschist facies.The Copley Greenstone consists of massive flows and pyroclastic deposits in the lower part that are overlain by pillow lavas. No sediments are interlayered in the volcanic pile except in the easternmost outcrop area, where sandstones with granitic debris and shaly tuffs are interbedded in the uppermost flows. High-Mg andesites occur only near the top of the basic volcanic succession. The Balaklala Rhyolite is formed of massive flows, breccias, and tuffs.The Copley volcanic rocks, poor in titanium, belong to a low-K tholeiitic suite formed in an island-arc geodynamic environment. The occurrence of olivine with chromium spinels in almost all the lava types, the enrichment in magnesium, chromium, and nickel, and the depletion in hygromagmaphile elements suggest that magmatic differentiation was a marginal process. The Balaklala Rhyolite shows very homogeneous petrographic and geochemical features, characteristic of tholeittic products.From its characteristics here described (pillowed flows, lack of sedimentation, presence of high-Mg andesites and low-K rhyolites, bimodality of the volcanism) the Early Devonian volcanic sequence represents an immature island arc related to a back-arc basin, similar to the present-day Mariana island arc.

The mid-Paleozoic volcanics of northern Sierra Nevada consist of the Sierra Buttes rhyolites, the Taylor basalts and andesites, and the Keddie Ridge basalt–latite–rhyolite suite. The Sierra Buttes calc-alkaline rhyolites display strong light rare-earth element enrichment and negative εNd values. The Taylor basalts and andesites in the northern Hough and Genesee blocks exhibit calc-alkaline affinities (REE rare-earth element patterns highly enriched in LREE), whereas in the southern Hough block they are tholeiitic (flat rare-earth element patterns). The abundance of silicic lavas, the low εNd values of both the Sierra Buttes and Taylor volcanics and the δ18O values of the Sierra Buttes rhyolite and Bowman Lake trondjhemite provide evidence that the northern Sierra Nevada island arc was continent based. The Keddie Ridge differentiated volcanics, characterized by high Zr, Y, Nb, K, and light rare-earth elements, are geochemically similar to a shoshonite suite. Their eruption at the end of the mid-Paleozoic volcanic episode suggests a reversal of subduction, uplift, and block faulting in the island arc.The mid-Paleozoic volcanics of the northern Sierra Nevada are thought to represent the remnant of a mature island arc because calc-alkaline rocks predominate over tholeiitic ones, the lavas display a K enrichment with time, and the volcanics are evolved in their isotopes, compared with rocks erupted in young or primitive island arcs.

The structural and electrical properties of different (TMTTF) 2 MF 6 compounds are described and the role of the anion size is investigated through the behaviour of the SbF 6 salt for which a critical increase of the resistivity occurs below 154 K. The effects of alloying (TMTTF) 2 SbF 6 with AsF 6 or PF 6 is also studied and we show that this electrical anomaly still exists for small amount of doping. Finally the existence of structural instabilities involving centrosymmetrical anions is briefly discussed Etude des proprietes structurales et electriques de ces sels ou l'on etudie le role de la taille de l'anion, a partir du comportement du sel de SbF 6 pour lequel un accroissement critique de resistivite est observe a 154 K. Effet du dopage de (TMTTF) 2 SbF 6 par AsF 6 ou PF 6 : l'anomalie de resistivite persiste aux faibles taux de dopage. Discussion de l'existence d'instabilites structurales impliquant des anions centrosymetriques

Cenozoic andesitic volcanism of Logudoro and Bosano correspond to three successive eruptive cycles composed of high alumina basalts, andesites (predominant), dacites, and, more sparsely, rhyolites. All these rocks belong to the calc-alkali serie. In the two first series, a progressive chemical evolution is shown from the saturated and oversaturated basaltic rocks to the dacites. In basaltic rocks, the variation of chemical composition may be related to the segregation of mafic minerals; the segregation of plagioclase appears in andesites. On the other hand, each andesitic serie has distinct evolutive chemical properties. All rocks of this calc-alkali association are relatively enriched in potassium. In Sardinia, the contents of this element increase Northward and suggest a deepening of a Benioff zone in the same direction. Moreover, the Logudoro region is caracterised by irregular distribution of potassium, with very local enrichment, particularly in andesites. These enrichments may be related to a crustal contamination.

Various physical properties of several radical-anion salts of a series of ternary compounds made with TCNQ, iodine and quaternary ammonium are described. Several phase transitions are found at low temperature. Following a recent structural study of one of these salts, the role of the counterions is discussed to explain the different behaviours found in the series. Finally, a unified description of the series involving both the interactions between the TCNQ chains and with the two counterions (iodine and ammonium) is presented Mesures et analyse de donnees pour la conductivite electrique, la susceptibilite magnetique, la RPE et la chaleur massique de conducteurs organiques ternaires m + (ou m 2+ )-TCNQ-I 2 avec m + ou m 2+ un cation(dication) ammonium quaternaire. Detection de plusieurs transitions de phase a basse temperature. Interpretation des resultats par le role joue pour l'ion m + (m 2+ )

Most proposed geodynamic models integrate the northern Sierra Nevada and eastern Klamath Mountains in a single island-arc system. New petrological and geochemical data show that the Upper Devonian Sierra Buttes Formation of the northern Sierra Nevada displays important differences from the Lower Devonian Balaklala Formation of the eastern Klamath Mountains. The cale-alkalic affinity of the Sierra Buttes rhyolites (light rare earth element [REE] enriched, low e Nd ) suggests that they were erupted in a continent-based island arc. In contrast, the Lower Devonian Balaklala low-K tholeiitic rhyolites (light REE depleted, high e Nd ) are considered to be part of an intraoceanic island-arc sequence. Moreover, the Paleozoic tectogenesis of these two island-arc sequences is different. The Lower Devonian Balaklala rhyolites were affected by the Late Devonian-Early Carboniferous orogeny, whereas the Sierra Buttes Formation is on basement already affected by a pre-Late Devonian deformation. Therefore, at least after Carboniferous time and before Late Triassic time, the eastern Klamath and northeastern Sierra Nevada island arcs cannot be considered lateral counterparts.