Geochemical proxies of ocean circulation and weathering inputs: Radiogenic isotopes of Nd, Pb, Sr, Hf, and Os

Marine records of the radiogenic isotope composition of the elements neodymium (Nd), lead (Pb), hafnium (Hf), strontium (Sr), and osmium (Os) allow the reconstruction of past ontinental weathering inputs on different time scales as a function of their respective oceanic residence times. Sr and Os have oceanic residence times significantly longer than the global mixing time of the ocean and are efficiently mixed on a global scale. Their isotope composition changes on long time scales as a function of plate tectonics and major orogenies, which allows their use as precise stratigraphic tools for the entire Phanerozoic. In contrast, Hf, Pb, and in particular Nd, have residence times on the order of or shorter than the global mixing time of the ocean, which results in distinct isotopic signatures of water masses and allows the reconstruction of past water mass mixing and weathering inputs on both long and short time scales. Here applications of these isotopes systems with a focus on the shorter residence time tracers are reviewed (without claiming to be comprehensive) and problems and potential solutions are discussed. Keywords: Radiogenic isotopes, paleo-oceanography, ocean circulation, water mass mixing, continental weatherin

Induction of distinct plant cell death programs by secreted proteins from the wheat pathogen Zymoseptoria tritici

Cell death processes in eukaryotes shape normal development and responses to the environment. For plant–microbe interactions, initiation of host cell death plays an important role in determining disease outcomes. Cell death pathways are frequently initiated following detection of pathogen-derived molecules which can lead to resistance or susceptibility to disease depending on pathogen lifestyle. We previously identified several small secreted proteins (SSPs) from the wheat-infecting fungus Zymoseptoria tritici that induce rapid cell death in Nicotiana benthamiana following Agrobacterium-mediated delivery and expression (agroinfiltration). Here we investigated whether the execution of host cells was mechanistically similar in response to different Z. tritici SSPs. Using RNA sequencing, we found that transient expression of four Z. tritici SSPs led to massive transcriptional reprogramming within 48 h of agroinfiltration. We observed that distinct host gene expression profiles were induced dependent on whether cell death occurs in a cell surface immune receptor-dependent or -independent manner. These gene expression profiles involved differential transcriptional networks mediated by WRKY, NAC and MYB transcription factors. In addition, differential expression of genes belonging to different classes of receptor-like proteins and receptor-like kinases was observed. These data suggest that different Z. tritici SSPs trigger differential transcriptional reprogramming in plant cells

Pain during injections of botulinum toxin in children: Influence of the localization technique

Objective In this study, we consider two localization techniques used in injections of botulinium toxin in children: electrical stimulation and ultrasound. The hypothesis of this work was that injections performed without stimulation would be less painful. Patients and methods Monocentric prospective study, with 107 sessions of lower limb injections. Two groups of children were compared: localization by ultrasound only (60 children), detection by stimulation only or by stimulation combined with ultrasound (47 children). Pain assessment was performed by the child or an accompanying party using the Visual Analog Scale (VAS) and by a health care team using the Face, Legs, Activity, Cry, Consolability (FLACC). Results A significant difference between the two groups was found in both self-report and by means of the behavioral observational pain scale. Indeed, VAS average and FLACC average were significantly higher with detection by stimulation than with ultrasound alone: 4.5 cm ± 2.54 versus 2.7 cm ± 2.27; P < 0.001 for VAS scale and 3.7 ± 2.1 versus 2.7 ± 2.3; P < 0.05 for FLACC scale. Conclusion When compared to ultrasound detection, localization by electrostimulation appears to increase the overall pain caused during injections of botulinum toxin in children

Plan de acción frente al consumismo global de la Nueva Economía: Revelaciones sobre economía, empresa y consumo del s. XXI

Este estudio crítico y revisionista, de corte interdisciplinario (entre Humanidades y Ciencias Sociales), alerta sobre los peligros de avanzar hacia una sociedad masa global de consumo, donde se acentúe la deshumanización y asocialización, al primarse el tener al ser (el bienestar a la felicidad, el negocio al ocio, la empresa al oficio, la pulsión a la experiencia, etc.). Se ofrece así un plan de acción que va de lo más general (retirando los velos de confusión que impiden reconocer el mundo posglobalizado y estudiarlo tal como es), pasando a centrar la atención en las complejas reglas económicas y empresariales del nuevo milenio, para terminar evaluando los riesgos de la inautenticidad del actual consumidor.This is a critical and reviewer study, under an interdisciplinary approach (between Liberal Arts and Social Sciences), which warns to move on a global mass consumer society and its dangers, by the accentuated lost of humanity and sociality, because the priority of the having-issue than the been-issue (the preference of welfare than happiness, the business than the recreation, the company than the profession, the desire than the experience, etc.). The structure of the paper goes from general view (removing the confusion veils that make impossible the recognition of the post-globalized World and its study), to particular view (focusing on the complex economic and business rules in the new millennium), and the risk evaluation of the non-authenticity of the current consumer

Syntheses and structure of molybdenum(O) dimers based on tetracyanobiimidazole

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25037/1/0000464.pd

Evidence for intense REE scavenging at cold seeps from the Niger Delta margin

International audienceFor many trace elements, continental margins are the location of intense exchange processes between sediment and seawater, which control their distribution in the water column, but have yet to be fully understood. In this study, we have investigated the impact of fluid seepage at cold seeps on the marine cycle of neodymium. We determined dissolved and total dissolvable (TD) concentrations for REE and well-established tracers of fluid seepage (CH4, TDFe, TDMn), and Nd isotopic compositions in seawater samples collected above cold seeps and a reference site (i.e. away from any fluid venting area) from the Niger Delta margin. We also analyzed cold seep authigenic phases and various core-top sediment fractions (pore water, detrital component, easily leachable phases, uncleaned foraminifera) recovered near the hydrocast stations. Methane, TDFe and TDMn concentrations clearly indicate active fluid venting at the studied seeps, with plumes rising up to about 100 m above the seafloor. Depth profiles show pronounced REE enrichments in the non-filtered samples (TD concentrations) within plumes, whereas filtered samples (dissolved concentrations) exhibit slight REE depletion in plumes relative to the overlying water column and display typical seawater REE patterns. These results suggest that the net flux of REE emitted into seawater at cold seeps is controlled by the presence of particulate phases, most probably Fe-Mn oxyhydroxides associated to resuspended sediments. At the reference site, however, our data reveal significant enrichment for dissolved REE in bottom waters, that clearly relates to diffusive benthic fluxes from surface sediments. Neodymium isotopic ratios measured in the water column range from εNd ~−15.7 to − 10.4. Evidence that the εNd values for Antarctic Intermediate waters (AAIW) differed from those reported for the same water mass at open ocean settings shows that sediment/water interactions take place in the Gulf of Guinea. At each site, however, the bottom water εNd signature generally differs from that for cold seep minerals, easily leachable sediment phases, and detrital fractions from local sediments, ruling out the possibility that seepage of methane-rich fluids and sediment dissolution act as a substantial source of dissolved Nd to seawater in the Gulf of Guinea. Taken together, our data hence suggest that co-precipitation of Fe-Mn oxyhydroxide phases in sub-surface sediments leads to quantitative scavenging of dissolved REE at cold seeps, preventing their emission into bottom waters. Most probably, it is likely that diffusion from suboxic surface sediments dominates the exchange processes affecting the marine Nd cycle at the Niger Delta margin

CIVA Workstation for NDE: Mixing of NDE Techniques and Modeling

Non Destructive Examination (NDE) plays an important role in numerous industrial fields. They are used both in production tests (improvement of product quality, process monitoring) and in facility inspections (installation safety, component life times). Various types of inspections are widely used: radiography, ultrasonics, eddy currents, etc. The choice of an inspection technique is made on the basis of different criteria: type of material to be tested, type of defects sought, detection or characterization, inspection time and cost. In some cases, either to compare the capabilities of different techniques, or to use complementary inspection methods, the same components are examined with different procedures. In these cases, it is very useful to have a single evaluation tool allowing direct comparison of the methods. This tool is indispensable for directly convoluting signals from two inspection methods.</p

Synthesis and reactivity of rhodium(I) and iridium(I) complexes of the dianions of 2,3-pyrazinedicarboxylic and 2,5-pyrazinedicarboxylic acid

Rhodium and iridium complexes of the title ligands have been prepared containing cyclooctadiene, carbonyl, phosphine and phosphite ancillary ligands. The complexes are mononuclear or dinuclear depending on the method of preparation and the leaving group basicity. The geometries of the complexes derived from the 2,3- and 2,5-dianions show marked differences owing to differences in the steric interaction between the carboxyl groups. Clear structural assignments were made possible by the symmetry requirements revealed by the infrared and NMR spectra.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28667/1/0000484.pd

Synthesis and X-ray crystal structure of a dinuclear platinum hydride complex of tetracyanobiimidazole

Reaction of the diacid form of tetracyanobiimidazole via oxidative addition with two equivalents of Pt(PPh3)4 produces a dinuclear complex whose structure is solved by X-ray analysis. The presence of dihydride is confirmed by observation of IR shift of a deuterium-labelled compound.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26946/1/0000512.pd

Complexes of tetracyanobiimidazole.4.dimers of Cu(I)

In this paper we described dimeric complexes of Cu(I) with 4,4',5,5'-tetracyano-2,2'-biimidazole (H2Tcbiim). These compounds contain the dianion (Tcbiim2-) acting as a quadridentate bridge betwee Cu(I) ions in combinations with phosphine, phosphite, pyridine, and quinuclidine ligands. Syntheses and interconversions among these species are recorded. The structure of Cu2[P(OPh)3]2(Py)2Tcbiim Py was determined by X-ray crystallography. The composition Cu2P2O6C61N11H45 crystallizes in the P triclinic space group with A = 10.456(3) A, B = 15.060(5) A, C = 10.438(2) A, [alpha] = 94.89(2), [beta] = 115.93(2), [gamma] = 72.76(2) and Z = 1 molecule per cell. A final agreement of R = 0.035, Rw = 0.042 was obtained for 2743 observed reflections. The dimeric molecule has an inversion center between the 2,2' carbon atoms of Tcbiim2-. Each Cu atom is tetrahedrally coordinated with angles ranging from 101[deg]-126[deg]. As a result of steric crowding by the phenyl rings of P(OPh)3 the copper atoms are somewhat sequestered. The influence of the stric and electronic factors can be seen in the oxidation potentials obtained from cyclic voltammetry. The potentials for the successive one electron oxidation of the dimers vary greatly with the donor strength of the ligands.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24723/1/0000145.pd