88 research outputs found
Mesophases in Nearly 2D Room-Temperature Ionic Liquids
Computer simulations of (i) a [C12mim][Tf2N] film of nanometric thickness
squeezed at kbar pressure by a piecewise parabolic confining potential reveal a
mesoscopic in-plane density and composition modulation reminiscent of
mesophases seen in 3D samples of the same room-temperature ionic liquid (RTIL).
Near 2D confinement, enforced by a high normal load, relatively long aliphatic
chains are strictly required for the mesophase formation, as confirmed by
computations for two related systems made of (ii) the same [C12mim][Tf2N]
adsorbed at a neutral solid surface and (iii) a shorter-chain RTIL
([C4mim][Tf2N]) trapped in the potential well of part i. No in-plane modulation
is seen for ii and iii. In case ii, the optimal arrangement of charge and
neutral tails is achieved by layering parallel to the surface, while, in case
iii, weaker dispersion and packing interactions are unable to bring aliphatic
tails together into mesoscopic islands, against overwhelming entropy and
Coulomb forces. The onset of in-plane mesophases could greatly affect the
properties of long-chain RTILs used as lubricants.Comment: 24 pages 10 figure
Beyond ‘geo-economics’: advanced unevenness and the anatomy of German austerity
This article aims to shed new light on Germany’s domineering role in the eurocrisis. I argue that the realist-inspired depiction of Germany as a ‘geo-economic power’, locked into zero-sum competition with its European partners, is built around an empty core: unable to theorise how anarchy shapes the calculus of states where security competition has receded, it cannot explain why German state managers have insisted on an austerity response to the crisis despite its significant risks and costs even for Germany itself. To unlock this puzzle, this article outlines a version of uneven and combined development (UCD) that is better able to capture the international pressures and opportunities faced by policy elites in advanced capitalist states that no longer encounter one another as direct security rivals. Applied to Germany, this lens reveals a twofold unevenness in the historical structures and growth cycles of capitalist economies that shape its contradictory choice for austerity. In the long run, the reorientation of the export-dependent German economy from Europe towards Asian and Latin American late industrialisers renders the structural adjustment of the eurozone an opportunity—from the cost-saving view of German manufacturers producing in the European home market for export abroad, as well as for German state officials keen to sustain a crumbling class compromise centred on Germany’s world market success. In the short term, however, its exposed position between the divergent post-crisis trajectories of the US and Europe accelerates pressures for austerity beyond what German state and corporate elites would otherwise consider feasible
Functional Induction of the Cystine-Glutamate Exchanger System Xc- Activity in SH-SY5Y Cells by Unconjugated Bilirubin
We have previously reported that exposure of SH-SY5Y neuroblastoma cells to unconjugated bilirubin (UCB) resulted in a marked up-regulation of the mRNA encoding for the Na+ -independent cystine∶glutamate exchanger System Xc− (SLC7A11 and SLC3A2 genes). In this study we demonstrate that SH-SY5Y cells treated with UCB showed a higher cystine uptake due to a significant and specific increase in the activity of System Xc−, without the contribution of the others two cystine transporters (XAG− and GGT) reported in neurons. The total intracellular glutathione content was 2 folds higher in the cells exposed to bilirubin as compared to controls, suggesting that the internalized cystine is used for gluthathione synthesis. Interestingly, these cells were significantly less sensitive to an oxidative insult induced by hydrogen peroxide. If System Xc− is silenced the protection is lost. In conclusion, these results suggest that bilirubin can modulate the gluthathione levels in neuroblastoma cells through the induction of the System Xc−, and this renders the cell less prone to oxidative damage
Allele specific repair of splicing mutations in cystic fibrosis through AsCas12a genome editing.
Funder: Fondazione Fibrosi Cistica - FFC#1/2017Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the CFTR gene. The 3272-26A>G and 3849+10kbC>T CFTR mutations alter the correct splicing of the CFTR gene, generating new acceptor and donor splice sites respectively. Here we develop a genome editing approach to permanently correct these genetic defects, using a single crRNA and the Acidaminococcus sp. BV3L6, AsCas12a. This genetic repair strategy is highly precise, showing very strong discrimination between the wild-type and mutant sequence and a complete absence of detectable off-targets. The efficacy of this gene correction strategy is verified in intestinal organoids and airway epithelial cells derived from CF patients carrying the 3272-26A>G or 3849+10kbC>T mutations, showing efficient repair and complete functional recovery of the CFTR channel. These results demonstrate that allele-specific genome editing with AsCas12a can correct aberrant CFTR splicing mutations, paving the way for a permanent splicing correction in genetic diseases
Modulation of Mrp1 (ABCc1) and Pgp (ABCb1) by Bilirubin at the Blood-CSF and Blood-Brain Barriers in the Gunn Rat
Accumulation of unconjugated bilirubin (UCB) in the brain causes bilirubin encephalopathy. Pgp (ABCb1) and Mrp1 (ABCc1), highly expressed in the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB) respectively, may modulate the accumulation of UCB in brain. We examined the effect of prolonged exposure to elevated concentrations of UCB on expression of the two transporters in homozygous, jaundiced (jj) Gunn rats compared to heterozygous, not jaundiced (Jj) littermates at different developmental stages (2, 9, 17 and 60 days after birth). BBB Pgp protein expression was low in both jj and Jj pups at 9 days (about 16–27% of adult values), despite the up-regulation in jj animals (2 and 1.3 fold higher than age matched Jj animals at P9 and P17–P60, respectively); Mrp1 protein expression was barely detectable. Conversely, at the BCSFB Mrp1 protein expression was rather high (60–70% of the adult values) in both jj and Jj at P2, but was markedly (50%) down-regulated in jj pups starting at P9, particularly in the 4th ventricle choroid plexuses: Pgp was almost undetectable. The Mrp1 protein down regulation was accompanied by a modest up-regulation of mRNA, suggesting a translational rather than a transcriptional inhibition. In vitro exposure of choroid plexus epithelial cells obtained from normal rats to UCB, also resulted in a down-regulation of Mrp1 protein. These data suggest that down-regulation of Mrp1 protein at the BSCFB, resulting from a direct effect of UCB on epithelial cells, may impact the Mrp1-mediated neuroprotective functions of the blood-cerebrospinal fluid barrier and actually potentiate UCB neurotoxicity
Effect of different parameters on the in situ thermal conductance evaluation
In the last years many studies have been carried out on the possible improvements of the in situ thermal
conductance measurement; as well known, this has to be derived by recorded values of temperatures
and heat fluxes. A big effort has been addressed in the implementation and comparison of different
analysis methods. The aim of this paper is to widen the existent literature in the study of the influence of
different kinds of input data on the final result. First the problem of analysing input data with significant
drift in temperature is considered, adopting both nominal clean and noise affected data. Then the effect
due to the presence of the Heat Flux Meter (HFM) on the thermal field of the testing element has been
analysed, as well as the possibility of recordingHFMsurface temperature. These studies are basedonFinite
Element Method (FEM) simulations; both nominal clean and noise affected data have been considered
as input. Finally, a difference in emissivity between the heat flux meter and internal plaster surface has
been analysed by means of FEM simulations based on nominal clean data. An overall estimation of the
occurred deviations in the different cases is shown
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