570 research outputs found

    Azo Complexes of Osmium(II): Preparation and Reactivity of Organic Azide and Hydrazine Derivatives

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    Seismic modeling using the frozen Gaussian approximation

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    We adopt the frozen Gaussian approximation (FGA) for modeling seismic waves. The method belongs to the category of ray-based beam methods. It decomposes seismic wavefield into a set of Gaussian functions and propagates these Gaussian functions along appropriate ray paths. As opposed to the classic Gaussian-beam method, FGA keeps the Gaussians frozen (at a fixed width) during the propagation process and adjusts their amplitudes to produce an accurate approximation after summation. We perform the initial decomposition of seismic data using a fast version of the Fourier-Bros-Iagolnitzer (FBI) transform and propagate the frozen Gaussian beams numerically using ray tracing. A test using a smoothed Marmousi model confirms the validity of FGA for accurate modeling of seismic wavefields.Comment: 5 pages, 8 figure

    Non-Saccharomyces Commercial Starter Cultures: Scientific Trends, Recent Patents and Innovation in the Wine Sector.

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    For 15 years, non-Saccharomyces starter cultures represent a new interesting segment in the dynamic field of multinationals and national companies that develop and sell microbial-based biotechnological solutions for the wine sector. Although the diversity and the properties of non-Saccharomyces species/strains have been recently fully reviewed, less attention has been deserved to the commercial starter cultures in term of scientific findings, patents, and their innovative appli-cations. Considering the potential reservoir of biotechnological innovation, these issues represent an under-estimated possible driver of coordination and harmonization of research and development activities in the field of wine microbiology. After a wide survey, we encompassed 26 different commercial yeasts starter cultures formulated in combination with at least one non-Saccharomyces strain. The most recent scientific advances have been explored delving into the oenological significance of these commercial starter cultures. Finally, we propose an examination of patent literature for the main yeasts species commercialised in non-Saccharomyces based products. We highlight the presence of asymmetries among scientific findings and the number of patents concerning non-Saccharomyces-based commercial products for oenological purposes. Further in-vestigations on these microbial resources might open new perspectives and stimulate attractive in-novations in the field of wine-making biotechnologies

    Denitrification and inference of nitrogen sources in the karstic Floridan Aquifer

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    Aquifer denitrification is among the most poorly constrained fluxes in global and regional nitrogen budgets. The few direct measurements of denitrification in groundwaters provide limited information about its spatial and temporal variability, particularly at the scale of whole aquifers. Uncertainty in estimates of denitrification may also lead to underestimates of its effect on isotopic signatures of inorganic N, and thereby confound the inference of N source from these data. In this study, our objectives are to quantify the magnitude and variability of denitrification in the Upper Floridan Aquifer (UFA) and evaluate its effect on N isotopic signatures at the regional scale. Using dual noble gas tracers (Ne, Ar) to generate physical predictions of N<sub>2</sub> gas concentrations for 112 observations from 61 UFA springs, we show that excess (i.e. denitrification-derived) N<sub>2</sub> is highly variable in space and inversely correlated with dissolved oxygen (O<sub>2</sub>). Negative relationships between O<sub>2</sub> and δ<sup>15</sup>N<sub>NO3</sub> across a larger dataset of 113 springs, well-constrained isotopic fractionation coefficients, and strong <sup>15</sup>N:<sup>18</sup>O covariation further support inferences of denitrification in this uniquely organic-matter-poor system. Despite relatively low average rates, denitrification accounted for 32 % of estimated aquifer N inputs across all sampled UFA springs. Back-calculations of source δ<sup>15</sup>N<sub>NO3</sub> based on denitrification progression suggest that isotopically-enriched nitrate (NO<sub>3</sub><sup>–</sup>) in many springs of the UFA reflects groundwater denitrification rather than urban- or animal-derived inputs

    Expression of the endocannabinoid receptors in human fascial tissue.

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    open7noCannabinoid receptors have been localized in the central and peripheral nervous system as well as on cells of the immune system, but recent studies on animal tissue gave evidence for the presence of cannabinoid receptors in different types of tissues. Their presence was supposed also in myofascial tissue, suggesting that the endocannabinoid system may help resolve myofascial trigger points and relieve symptoms of fibromyalgia. However, until now the expression of CBI (cannabinoid receptor I) and CB2 (cannabinoid receptor 2) in fasciae has not yet been established. Small samples of fascia were collected from volunteers patients during orthopedic surgery. For each sample were done a cell isolation, immunohistochemical investigation (CB1 and CB2 antibodies) and real time RT-PCR to detect the expression of CB1 and CB2. Both cannabinoid receptors are expressed in human fascia and in human fascial fibroblasts culture cells. although to a lesser extent than the control gene. We can assume that the expression of mRNA and protein of CBI and CB2 receptors in fascial tissue are concentrated into the fibroblasts This is the first demonstration that the fibroblasts of the muscular fasciae express CBI and CB2. The presence of these receptors could help to provide a description of cannabinoid receptors distribution and to better explain the role of fasciae as pain generator and the efficacy of some fascial treatments. Indeed the endocannabinoid receptors of fascial fibroblasts can contribute to modulate the fascial fibrosis and inflammation.noneopenFede, C; Albertin, G; Petrelli, L; Sfriso, Mm; Biz, C; De Caro, R; Stecco, CFede, C; Albertin, Giovanna; Petrelli, Lucia; Sfriso, MARIA MARTINA; Biz, Carlo; DE CARO, Raffaele; Stecco, Carl

    Bioinformatics and mathematical modelling in the study of receptor-receptor interactions and receptor oligomerization: focus on adenosine receptors.

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    none8sìThe concept of intra-membrane receptor-receptor interactions (RRIs) between different types of G protein-coupled receptors (GPCRs) and evidence for their existence was introduced by Agnati and Fuxe in 1980/81 through the biochemical analysis of the effects of neuropeptides on the binding characteristics of monoamine receptors in membrane preparations from discrete brain regions and functional studies of the interactions between neuropeptides and monoamines in the control of specific functions such as motor control and arterial blood pressure control in animal models. Whether GPCRs can form high-order structures is still a topic of an intense debate. Increasing evidence, however, suggests that the hypothesis of the existence of high-order receptor oligomers is correct. A fundamental consequence of the view describing GPCRs as interacting structures, with the likely formation at the plasma membrane of receptor aggregates of multiple receptors (Receptor Mosaics) is that it is no longer possible to describe signal transduction simply as the result of the binding of the chemical signal to its receptor, but rather as the result of a filtering/integration of chemical signals by the Receptor Mosaics (RMs) and membrane-associated proteins. Thus, in parallel with experimental research, significant efforts were spent in bioinformatics and mathematical modelling. We review here the main approaches that have been used to assess the interaction interfaces allowing the assembly of GPCRs and to shed some light on the integrative functions emerging from the complex behaviour of these RMs. Particular attention was paid to the RMs generated by adenosine A(2A), dopamine D-2, cannabinoid CB1, and metabotropic glutamate mGlu(5) receptors (A(2A). D-2, CB1, and mGlu(5), respectively), and a possible approach to model the interplay between the D-2-A(2A)-CB1 and D-2-A(2A)-mGlu(5) trimers is proposed. This article is part of a Special Issue entitled: "Adenosine Receptors". (C) 2010 Elsevier B.V. All rights reserved.openD. GUIDOLIN; F. CIRUELA; S. GENEDANI; M. GUESCINI; C. TORTORELLA; G. ALBERTIN; K. FUXE; L.F. AGNATID., Guidolin; F., Ciruela; S., Genedani; Guescini, Michele; C., Tortorella; G., Albertin; K., Fuxe; L. F., Agnat

    Role of the anterior endoderm in cardiac specification

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    The heart is the first functional organ of embryogenesis in many vertebrates, however little is known about the early specification events of cardiogenesis. Evidence in the chick and amphibian suggests a requirement for the anterior endoderm in cardiac induction to direct mesoderm toward a cardiac fate. Furthermore, the signals responsible for specification and their mode of action are unknown. Several signalling pathways, including FGF, Nodal, BMP and Wnt have been implicated. However, as these pathways have other roles in early embryogenesis a specific role in cardiac induction has been difficult to define. We have devised a model testing the cardiac-inducing activity of the anterior endoderm addressing its ability to re-specify pluripotent embryonic ectoderm upon conjugation. We have shown that the anterior endoderm is sufficient to induce robust expression of cardiac markers and formation of contractile tissue in the responder. Characterisation of the model showed the anterior endoderm produces a specific signal skeletal muscle is not induced, distinguishing it from general mesoderm induction. The cardiac-inducing capacity of the anterior endoderm was not uniform as it was restricted to the most anterior regions of the anterior endoderm, correlating with expression of Hex. The cardiac-inducing signal requires two hours of interaction with the responding tissue during gastrulation to produce an effect. Further involvement of the anterior endoderm beyond specification of cardiac precursors was not required. The model provided the basis to investigate the early signalling events of specification. Whereas BMP signalling was not necessary for cardiac induction by the endoderm, an essential requirement for FGF and Nodal pathways was shown. Timed inhibition revealed both were required during the first hour of conjugation, while sustained ERK activation was needed for at least four hours. In addition it was shown that elevated Wnt/p-catenin signalling during specification had no effect, while sustained activation antagonised cardiogenesis. Further analysis revealed Wnt/p-catenin has no direct role in specification, but suppression or low activity was required prior to the onset of cardiac differentiation. Therefore, this work established a simple and experimentally amenable assay for elucidating the mechanisms of cardiac specification.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Sexual function after vaginal erbium laser: the results of a large, multicentric, prospective study.

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    The aim of this multicentric, prospective study was to evaluate the effects of vaginal erbium laser (VEL-SMOOTH®) on sexual function in postmenopausal women suffering from the genitourinary syndrom..
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