FACCENDA AND CAPITANIO: SEISMIC ANISOTROPY

[1] Inferring the circulation of the mantle around subducting plates from surface measurements of shear wave splitting patterns remains to date elusive. To assist the interpretation of the seismic signal and its relation with the mantle circulation pattern, we present a new methodology to compute the seismic anisotropy directly from the flow in the upper mantle of 3-D numerical models of Earth-like subduction. This computational strategy accounts for the non-steady-state evolution of subduction zones yielding mantle fabrics that are more consistent with the deformation history than previously considered. In the subduction models, a strong mantle fabric develops throughout the upper mantle with a magnitude of the anisotropy that is proportional to the amount of subduction and is independent of the subduction rate. The sub-slab upper mantle is characterized by two domains with different fabrics: at shallow depth, the mantle entrained with the subducting slab develops trench-perpendicular directed anisotropy due to simple shear deformation, while in the deeper mantle, slab rollback induces pure shear deformation causing trench-parallel extension and fast seismic directions. Subducting plate advance favors the development of the fabric in the entrained mantle domain, while slab retreat increases the trench-parallel anisotropy in the deeper upper mantle. In the deeper domain, the strength of the fabric is proportional to the horizontal divergence of the flow and weakens from the slab edges toward the center. As such, strong trench-parallel anisotropy forms below retreating and relatively narrow slabs or at the margins of wider plates. The synthetic SKS splitting patterns calculated in the fore arc are controlled by the magnitude of the anisotropy in the upper domain, with trench-perpendicular fast azimuths in the center of large plates and trench parallel toward the plate edges. Instead, above relatively narrow, retreating slabs (≤600 km and low subduction partitioning ratio [SPR]), azimuths are trench parallel due to the strong anisotropy in the lower sub-slab domain. In all models, the anisotropy in the back arc and on the sides of the subducting plate is, respectively, trench perpendicular and sub-parallel to the return flow at depth. Results from our regional scale models may help to infer the flow and composition of the upper mantle by comparison with the wide range of subduction zones seismic data observed globally

Native larval parasitoids (Hymenoptera) of Frugivorous Tephritoidea (Kiptera) in South Pantanal, Brazil.

El objetivo de este estudio es evaluar la incidencia de los parasitoides (Hymenoptera) sobre larvara de tephritidae (moscas de la fruta) y los Lonchacidae frugivoros, en varias especies frutiferas nativas y exoticas en el Pantal sur Mato Grosso do Sul, Brasil. Noventa Y dos especies de frutas de 36 familias y 22 órdenes fueron evaluadas..

On the Origin of Radial Anisotropy Near Subducted Slabs in the Midmantle

Recent seismic studies indicate the presence of seismic anisotropy near subducted slabs in the transition zone and uppermost lower mantle (mid-mantle). In this study, we investigate the origin of radial anisotropy in the mid-mantle using 3-D geodynamic subduction models combined with mantle fabric simulations. These calculations are compared with seismic tomography images to constrain the range of possible causes of the observed anisotropy. We consider three subduction scenarios: (i) slab stagnation at the bottom of the transition zone; (ii) slab trapped in the uppermost lower mantle; and (iii) slab penetration into the deep lower mantle. For each scenario, we consider a range of parameters, including several slip systems of bridgmanite and its grain-boundary mobility. Modeling of lattice-preferred orientation shows that the upper transition zone is characterized by fast-SV radial anisotropy anomalies up to 121.5%. For the stagnating and trapped slab scenarios, the uppermost lower mantle is characterized by two fast-SH radial anisotropy anomalies of 3c+2% beneath the slab's tip and hinge. On the other hand, the penetrating slab is associated with fast-SH radial anisotropy anomalies of up to 3c+1.3% down to a depth of 2,000\ua0km. Four possible easy slip systems of bridgmanite lead to a good consistency between the mantle modeling and the seismic tomography images: [100](010), [010](100), [001](100), and (Formula presented.). The anisotropy anomalies obtained from shape-preferred orientation calculations do not fit seismic tomography images in the mid-mantle as well as lattice-preferred orientation calculations, especially for slabs penetrating into the deep lower mantle

Reduction of the ATPase inhibitory factor 1 (IF1) leads to visual impairment in vertebrates

In vertebrates, mitochondria are tightly preserved energy producing organelles, which sustain nervous system development and function. The understanding of proteins that regulate their homoeostasis in complex animals is therefore critical and doing so via means of systemic analysis pivotal to inform pathophysiological conditions associated with mitochondrial deficiency. With the goal to decipher the role of the ATPase inhibitory factor 1 (IF1) in brain development, we employed the zebrafish as elected model reporting that the Atpif1a−/− zebrafish mutant, pinotage (pnttq209), which lacks one of the two IF1 paralogous, exhibits visual impairment alongside increased apoptotic bodies and neuroinflammation in both brain and retina. This associates with increased processing of the dynamin-like GTPase optic atrophy 1 (OPA1), whose ablation is a direct cause of inherited optic atrophy. Defects in vision associated with the processing of OPA1 are specular in Atpif1−/− mice thus confirming a regulatory axis, which interlinks IF1 and OPA1 in the definition of mitochondrial fitness and specialised brain functions. This study unveils a functional relay between IF1 and OPA1 in central nervous system besides representing an example of how the zebrafish model could be harnessed to infer the activity of mitochondrial proteins during development

Microbiological quality of silage made from by-products of cassava starch extraction and viticulture

This study evaluated silages made with varying proportions of viticulture by-products (VC) and starch extraction from cassava (CSE). It attempted to determine the effects of these proportions on the microbial population, fermentative losses, and chemical composition. The treatments were specified as the proportions of VC in the silage (0 g/kg, 250 g/kg, 500 g/kg, 750 g/kg, and 1000 g/kg). Silages were  evaluated before (0) and after 1, 3, 7, 15, 30, and 60 days of ensiling. The experimental design was completely randomized with five  treatments, six storage times and four replications. The increased level of VC in the silage enhanced its dry matter content, ammonia  nitrogen (NH3-N), and buffering capacity, and reduced organic matter content. Fifteen days after ensiling, additional VC increased the concentration of soluble carbohydrates. The increased level of VC decreased the count of Clostridium spp. and lactic acid bacteria (LAB). The incidence of yeasts and enterobacteria was low in all treatments at all time points. Over time, losses as effluent and gases increased. Use of increasing proportions from VC in silage made with CSE increased the contents of dry matter and soluble carbohydrates and  reduced the fermentative losses of the silage. The increased amount of VC also favoured pH reduction and reduced the proliferation of undesirable yeasts, while increasing the population of LAB

Human Amniocytes Are Receptive to Chemically Induced Reprogramming to Pluripotency

Restoring pluripotency using chemical compounds alone would be a major step forward in developing clinical-grade pluripotent stem cells, but this has not yet been reported in human cells. We previously demonstrated that VPA_ AFS cells, human amniocytes cultivated with valproic acid (VPA) acquired functional pluripotency while remaining distinct from human embryonic stem cells (hESCs), questioning the relationship between the modulation of cell fate and molecular regulation of the pluripotency network. Here, we used single-cell analysis and functional assays to reveal that VPA treatment resulted in a homogeneous population of self-renewing non-transformed cells that fulfill the hallmarks of pluripotency, i.e., a short G1 phase, a dependence on glycolytic metabolism, expression of epigenetic modifications on histones 3 and 4, and reactivation of endogenous OCT4 and downstream targets at a lower level than that observed in hESCs. Mechanistic insights into the process of VPA-induced reprogramming revealed that it was dependent on OCT4 promoter activation, which was achieved independently of the PI3K (phosphatidylinositol 3-kinase)/ AKT/ mTOR (mammalian target of rapamycin) pathway or GSK3 beta inhibition but was concomitant with the presence of acetylated histones H3K9 and H3K56, which promote pluripotency. Our data identify, for the first time, the pluripotent transcriptional and molecular signature and metabolic status of human chemically induced pluripotent stem cells

Dried brewers’ grain as a replacement for soybean meal on nutrient digestibility and rumen parameters of cattle

The objective of this study was to determine the effect of replacing soybean meal with dried brewers’ grains (DBG) in intake and digestibility of the nutrients and the ruminal parameters of cattle. Four ruminal cannulated Jersey oxen with initial body weight of 662.7 ± 85.5 kg were distributed in a 4x4 Latin square design. The treatments were levels of 0%, 33%, 66% and 100% DBG replacing soybean meal in the diet. Dry matter (DM) and crude protein (CP) intake were not influenced by the treatments. There were linear increases in ether extract (EE), neutral detergent fibre (NDF) and acid detergent fibre (ADF) intakes because of higher levels of these nutrients in diets with DBG. Non-fibre carbohydrate (NFC) and total digestible nutrient (TDN) intake showed a decreasing linear effect. Dry matter and NFC digestibility decreased linearly with rising DBG levels, while EE, CP, NDF and ADF digestibilities were not affected. Ruminal pH was not influenced by DBG levels in the diet. There was a quadratic effect in ammonia nitrogen (NH3-N) concentration in the rumen, with the maximum occurring at a level of 36.7% DGB. The replacement of soybean meal with DBG in cattle diets did not alter DM intake and ruminal pH, but reduced TDN intake.Keywords: Ammonia nitrogen, by-product, digestibility, intake, p

Numerical simulations of an ocean/continent convergent system: influence of subduction geometry and mantle wedge hydration on crustal recycling

The effects of the hydration mechanism on continental crust recycling are analyzed through a 2D finite element thermo-mechanical model. Oceanic slab dehydration and consequent mantle wedge hydration are implemented using a dynamic method. Hydration is accomplished by lawsonite and serpentine breakdown; topography is treated as a free surface. Subduction rates of 1, 3, 5, 7.5 and 10 cm/y, slab angles of 30o, 45o and 60o and a mantle rheology represented by dry dunite and dry olivine flow laws, have been taken into account during successive numerical experiments. Model predictions pointed out that a direct relationship exists between mantle rheology and the amount of recycled crustal material: the larger the viscosity contrast between hydrated and dry mantle, the larger the percentage of recycled material into the mantle wedge. Slab dip variation has a moderate impact on the recycling. Metamorphic evolution of recycled material is influenced by subduction style. TPmax, generally representative of eclogite facies conditions, is sensitive to changes in slab dip. A direct relationship between subduction rate and exhumation rate results for different slab dips that does not depend on the used mantle flow law. Thermal regimes predicted by different numerical models are compared to PT paths followed by continental crustal slices involved in ancient and recent subduction zones, making ablative subduction a suitable pre-collisional mechanism for burial and exhumation of continental crust.Comment: 10 figures, 3 table

MicroRNAs Regulate Ca2+ Homeostasis in Murine Embryonic Stem Cells

MicroRNAs (miRNAs) are important regulators of embryonic stem cell (ESC) biology, and their study has identified key regulatory mechanisms. To find novel pathways regulated by miRNAs in ESCs, we undertook a bioinformatics analysis of gene pathways differently expressed in the absence of miRNAs due to the deletion of Dicer, which encodes an RNase that is essential for the synthesis of miRNAs. One pathway that stood out was Ca2+ signaling. Interestingly, we found that Dicer−/− ESCs had no difference in basal cytoplasmic Ca2+ levels but were hyperresponsive when Ca2+ import into the endoplasmic reticulum (ER) was blocked by thapsigargin. Remarkably, the increased Ca2+ response to thapsigargin in ESCs resulted in almost no increase in apoptosis and no differences in stress response pathways, despite the importance of miRNAs in the stress response of other cell types. The increased Ca2+ response in Dicer−/− ESCs was also observed during purinergic receptor activation, demonstrating a physiological role for the miRNA regulation of Ca2+ signaling pathways. In examining the mechanism of increased Ca2+ responsiveness to thapsigargin, neither store-operated Ca2+ entry nor Ca2+ clearance mechanisms from the cytoplasm appeared to be involved. Rather, it appeared to involve an increase in the expression of one isoform of the IP3 receptors (Itpr2). miRNA regulation of Itpr2 expression primarily appeared to be indirect, with transcriptional regulation playing a major role. Therefore, the miRNA regulation of Itpr2 expression offers a unique mechanism to regulate Ca2+ signaling pathways in the physiology of pluripotent stem cells

The Concise Guide to PHARMACOLOGY 2015/16:Voltage-gated ion channels

The Concise Guide to PHARMACOLOGY 2015/16 provides concise overviews of the key properties of over 1750 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.13350/full. Voltage-gated ion channels are one of the eight major pharmacological targets into which the Guide is divided, with the others being: G protein-coupled receptors, ligand-gated ion channels, other ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The Concise Guide is published in landscape format in order to facilitate comparison of related targets. It is a condensed version of material contemporary to late 2015, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in the previous Guides to Receptors & Channels and the Concise Guide to PHARMACOLOGY 2013/14. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and GRAC and provides a permanent, citable, point-in-time record that will survive database updates