126 research outputs found

    CO2-crystal wettability in potassic magmas. Implications for eruptive dynamics in light of experimental evidence for heterogeneous nucleation.

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    The volatile content in magmas is fundamental for the triggering and style of volcanic eruptions. Carbon dioxide, the second most abundant volatile component in magmas after H2O, is the first to reach saturation upon ascent and depressurization. We investigate experimentally CO2-bubble nucleation in trachybasalt and trachyte melts at high temperature and high pressure (HT and HP) through wetting-angle measurements on different (sialic, mafic or oxide) phenocryst phases. The presence of crystals lowers the supersaturation required for CO2- bubble nucleation up to 37 per cent (heterogeneous nucleation, HeN), with a minor role of mineral chemistry. Different from H2O-rich systems, feldspar crystals are effective in reducing required supersaturation for bubble nucleation. Our data suggest that leucite, the dominant liquidus phase in ultrapotassic systems at shallow depth (i.e. <100 MPa), facilitates late-stage, extensive magma vesiculation through CO2 HeN, which may explain the shifting of CO2-rich eruptive systems towards an apparently anomalous explosive behaviour

    Occurrence and transformation of illicit drugs in wastewater treatment plants.

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    Illicit drugs (IDs) and their metabolites have been recently recognized as a new group of water emerging contaminants (ECs) with potent psychoactive properties and unknown effects to the aquatic environment (Pal et al., 2013). IDs are excreted via urine and feces and arrive at wastewater treatment plants (WWTPs) where can reach ppb levels (Castiglioni et al., 2006). Over the past few years, it has been demonstrated that conventional biological processes in WWTPs are not or scarcely able to remove IDs. Thus, they are discharged into water bodies through the treated effluent (Postigo et al., 2011). Therefore, monitoring the IDs concentration in WWTPs can have a twofold advantage: i. increase knowledge on the amount of IDs discharged in the environment and estimate their effect; ii. estimating indirectly the community level consumption (Senta et al., 2014). The objective of this paper is to provide a comprehensive analysis of the occurrence and behaviour of illicit drugs and their metabolites in two Sicilian WWTPs. Specifically, two WWTPs (namely, WWTP-1 and WWTP-2) located at the north-western Sicilian coast have been monitored for 5 months (one sampling per week). The two WWTPs have a conventional scheme and mainly differ for their potentiality. Indeed, the average daily flow expressed as m3d-1 for WWTP-1 and WWTP-2 was equal to 153,600 and 19,704, respectively. Samples were analyzed for total suspended solids (TSS), illicit drugs and their metabolites (metham-phetamine; COC = cocaine; MDMA = 3,4-methylenedioxymethamphetamine; METH = methadone; EDDP = 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine; MDA = 3,4-methylenedioxy amphetamine; MDEA = 3,4-methylenedioxy ethylamphetamine; THC-COOH = 11-nor-9-carboxy-\u3949-tetrahydrocannabinol; BEG= Benzoylecgonine). In order to provide a fast and sensitive approach to quantify IDs, an automated online sample preparation method has been developed. The method uses a Thermo Scientific Transcend TLX-1 system powered by TurboFlowTM technology coupled with a TSQ Quantiva Triple Quadrupole Mass Spectrometer. Specifically, THC-COOH has been extracted from 75 \ub5L of pre-filtered water (using 7 and 0.4 \ub5m paper filters) by an online sample extraction method and quantified using an isotopic dilution approach between 30 and 2000 ng L-1

    The Relationship between Knowing Sign Language and Quality of Life among Italian People Who Are Deaf: A Cross-Sectional Study

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    Deafness is a medical condition with important relational implications. This conditioncould affect well-being and self-esteem and cause social anxiety. Sign language is not only a simplemimic but can be considered as a different kind of communication that could be protective for thosewho have learned it. However, some people do not use sign language because they think it canbe marginalizing. The present study aimed to compare the quality of life (QoL) between peoplewho learned Italian sign language as their first language with those who had never learned it orlearned it later. This cross-sectional study involved 182 deaf Italian adults (70.3% females) who wererecruited from Ente Nazionale Sordi (ENS) and by the main online deafness groups. The presentresults suggest that the deaf condition does not seem to significantly affect the dimensions of QoLpertaining to satisfaction and self-esteem, while it could have an effect on preventing high levels of social anxiety and in particular, the group who learned Italian sign language showed significantlyless social anxiety than those who had never learned it

    Nucleocytoplasmic transport: a thermodynamic mechanism

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    The nuclear pore supports molecular communication between cytoplasm and nucleus in eukaryotic cells. Selective transport of proteins is mediated by soluble receptors, whose regulation by the small GTPase Ran leads to cargo accumulation in, or depletion from the nucleus, i.e., nuclear import or nuclear export. We consider the operation of this transport system by a combined analytical and experimental approach. Provocative predictions of a simple model were tested using cell-free nuclei reconstituted in Xenopus egg extract, a system well suited to quantitative studies. We found that accumulation capacity is limited, so that introduction of one import cargo leads to egress of another. Clearly, the pore per se does not determine transport directionality. Moreover, different cargo reach a similar ratio of nuclear to cytoplasmic concentration in steady-state. The model shows that this ratio should in fact be independent of the receptor-cargo affinity, though kinetics may be strongly influenced. Numerical conservation of the system components highlights a conflict between the observations and the popular concept of transport cycles. We suggest that chemical partitioning provides a framework to understand the capacity to generate concentration gradients by equilibration of the receptor-cargo intermediary.Comment: in press at HFSP Journal, vol 3 16 text pages, 1 table, 4 figures, plus Supplementary Material include

    Identifying candidate genes affecting developmental time in Drosophila melanogaster: pervasive pleiotropy and gene-by-environment interaction

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    <p>Abstract</p> <p>Background</p> <p>Understanding the genetic architecture of ecologically relevant adaptive traits requires the contribution of developmental and evolutionary biology. The time to reach the age of reproduction is a complex life history trait commonly known as developmental time. In particular, in holometabolous insects that occupy ephemeral habitats, like fruit flies, the impact of developmental time on fitness is further exaggerated. The present work is one of the first systematic studies of the genetic basis of developmental time, in which we also evaluate the impact of environmental variation on the expression of the trait.</p> <p>Results</p> <p>We analyzed 179 co-isogenic single <it>P[GT1]-</it>element insertion lines of <it>Drosophila melanogaster </it>to identify novel genes affecting developmental time in flies reared at 25°C. Sixty percent of the lines showed a heterochronic phenotype, suggesting that a large number of genes affect this trait. Mutant lines for the genes <it>Merlin </it>and <it>Karl </it>showed the most extreme phenotypes exhibiting a developmental time reduction and increase, respectively, of over 2 days and 4 days relative to the control (a co-isogenic <it>P</it>-element insertion free line). In addition, a subset of 42 lines selected at random from the initial set of 179 lines was screened at 17°C. Interestingly, the gene-by-environment interaction accounted for 52% of total phenotypic variance. Plastic reaction norms were found for a large number of developmental time candidate genes.</p> <p>Conclusion</p> <p>We identified components of several integrated time-dependent pathways affecting egg-to-adult developmental time in <it>Drosophila</it>. At the same time, we also show that many heterochronic phenotypes may arise from changes in genes involved in several developmental mechanisms that do not explicitly control the timing of specific events. We also demonstrate that many developmental time genes have pleiotropic effects on several adult traits and that the action of most of them is sensitive to temperature during development. Taken together, our results stress the need to take into account the effect of environmental variation and the dynamics of gene interactions on the genetic architecture of this complex life-history trait.</p

    Study of the f(0)(1500)/f(2)(1565) production in the exclusive annihilation anti-n.anti-p -> pi+.pi+.pi- in flight

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    The spin-parity analysis of the (n) over bar p --> pi(+)pi(+)pi(-) exclusive reaction in flight is presented. The main aim is to study the (pi(+)pi(-)) invariant mass spectrum in the region around 1500 MeV. The analysis was performed with a Breit-Wigner parametrization for all the resonant states and, for the scalar sector in the mass region below 1.2 GeV, by means of a K-matrix-like treatment. It clearly shows the need for two states, a scalar one (0(++)) with mass and width (1522+/-25) MeV and (108+/-33) MeV, and a tensorial one (2(++)) with mass (1575 +/-18) MeV and width (119+/-24) MeV, respectively. In addition, the analysis requires the presence of a scalar state at (1280+/-55) MeV, (323+/-13) MeV broad, and of a second vectorial one, in addition to the rho(0)(770) signal, with mass and width (1348+/-33) MeV and (275+/-10) MeV, respectively

    Influence of N*-resonances on hyperon production in the channel pp->K+ Lambda p at 2.95, 3.20 and 3.30 GeV/c beam momentum

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    Hyperon production in the threshold region was studied in the reaction pp -> K+Lp using the time-of-flight spectrometer COSY-TOF. Exclusive data, covering the full phase-space, were taken at the three different beam momenta of p_beam=2.95, 3.20 and 3.30 GeV/c, corresponding to excess energies of epsilon=204, 285 and 316 MeV, respectively. Total cross-sections were deduced for the three beam momenta to be 23.9+/-0.8 +/-2.0 ub, 28.4+/-1.3 +/-2.2 ub and 35.0+/-1.3 +/-3.0 ub. Differential observables including Dalitz plots were obtained. The analysis of the Dalitz plots reveals a strong influence of the N(1650)-resonance at p_beam=2.95 GeV/c, whereas for the higher momenta an increasing relative contribution of the N(1710)- and/or of the N(1720)-resonance was observed. In addition, the pL-final-state interaction turned out to have a significant influence on the Dalitz plot distribution.Comment: accepted for publication at Physics Letters B; some minor text changes were done; also the scale of the ordinates of figure 9 has been changed

    Actin binding to WH2 domains regulates nuclear import of the multifunctional actin regulator JMY

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    © The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Molecular Biology of the Cell 23 (2012): 853-863, doi:10.1091/mbc.E11-12-0992.Junction-mediating and regulatory protein (JMY) is a regulator of both transcription and actin filament assembly. In response to DNA damage, JMY accumulates in the nucleus and promotes p53-dependent apoptosis. JMY's actin-regulatory activity relies on a cluster of three actin-binding Wiskott–Aldrich syndrome protein homology 2 (WH2) domains that nucleate filaments directly and also promote nucleation activity of the Arp2/3 complex. In addition to these activities, we find that the WH2 cluster overlaps an atypical, bipartite nuclear localization sequence (NLS) and controls JMY's subcellular localization. Actin monomers bound to the WH2 domains block binding of importins to the NLS and prevent nuclear import of JMY. Mutations that impair actin binding, or cellular perturbations that induce actin filament assembly and decrease the concentration of monomeric actin in the cytoplasm, cause JMY to accumulate in the nucleus. DNA damage induces both cytoplasmic actin polymerization and nuclear import of JMY, and we find that damage-induced nuclear localization of JMY requires both the WH2/NLS region and importin β. On the basis of our results, we propose that actin assembly regulates nuclear import of JMY in response to DNA damage.This work was supported by grants from the National Institutes of Health, an American Heart Association Predoctoral Fellowship (J.B.Z.), the Robert Day Allen Fellowship Fund (J.B.Z.), and a National Science Foundation Predoctoral Fellowship (B.B.)

    DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

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    We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR&nbsp;=&nbsp;2.05, 95%CI&nbsp;=&nbsp;1.39–3.02, p&nbsp;&lt;&nbsp;0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR&nbsp;=&nbsp;0.42, 95%CI&nbsp;=&nbsp;0.18–0.99, p&nbsp;=&nbsp;0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon
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