2,575 research outputs found
Lypd6: Ein neuartiger Modulator neuronaler nikotinischer Acetylcholinrezeptoren
Nikotinischce Acetylcholinrezeptoren (nAChRs) zeigen für unterschiedliche Agonisten spezifische Sensitivitäten und Desensitisierungskinetiken. Diese Rezeptoreigenschaften können z.B. durch Schlangenneurotoxine oder den damit verwandten endogenen Proteinen aus der uPAR-Ly6 Familie moduliert werden. In dieser Studie identifizieren wir Lypd6, ein Protein aus der Familie der u-PAR/Ly-6 Proteine, als neuartigen Modulator von nAchRs. Lypd6 verstärkt die Kalziumkomponente nikotininduzierter Ströme durch nAChRs in trigeminalen Neuronen, die dieses Protein überexprimieren. Dies konnte in vergleichenden Whole-Cell Patch-Clamp Studien und mikrofluorometrischen Messungen intrazellulärer Kalziumsignale bei Wildtyp- und transgenen Mäusen nachgewiesen werden. Im Gegensatz dazu führt ein Knock-Down der Lypd6-Expression mit Hilfe von spezifischer siRNA zu einer selektiven Verringerung der nikotininduzierten Kalziumströme. Pharmakologische Untersuchungen zeigen, dass heteromere nAchRs dabei eine Rolle spielen. Zusammengenommen stellt das Protein Lypd6 einen neuartigen Modulator von nAChRs dar, der durch den selektiven Anstieg der Kalziumpermeabilität durch den Kanal die Rezeptorfunktion beeinflusst.Modulation of the Calcium Conductance of Nicotinic Acetylcholine Receptors by Lypd6 The agonist binding sensitivity and desensitization kinetics of nicotinic acetylcholine receptors (nAChRs) can be modulated by snake venom neurotoxins and related endogenous small proteins of the uPAR-Ly6 family. Here we identify Lypd6, a distantly related member of the u-PAR/Ly-6 family expressed in neurons as a novel modulator of nAChRs. Lypd6 overexpressed in trigeminal ganglia neurons selectively enhanced the calcium-component of nicotine-evoked currents through nAChRs, as evidenced by comparative whole-cell patch clamp recordings and calcium-imaging in wildtype and transgenic mice overexpressing Lypd6. In contrast, a knockdown of Lypd6 expression using siRNAs selectively reduced nicotine-evoked calcium-currents. Pharmacological experiments revealed that the nAChRs involved in this process are heteromers. Taken together, Lypd6 seems to constitute a novel modulator of nAChRs that affects receptor function by selectively increasing calcium-influx through these ion channels
Iron Ore Tailings Dewatering: Measurement of Adhesion and Cohesion for Filter Press Operation
Globally, mining operators focus increasingly on tailings filtration to recover process water and store tailings more safely. Generally, required water contents below 20-w% are reached by using filter presses. To maintain high efficiency, complete cake detachment is needed because incomplete discharge reduces plant performance. However, filter cake discharge can occur in different ways, mainly influenced by adhesion of the filter cake to the filter cloth as well as by cohesion of the cake. Therefore, this study points out different major detachment behaviors and a theoretical approach to describe them. Furthermore, investigations on iron ore tailings filtrations were carried out to show the influences of different filter media, different filtration pressure and cake post-treatment on adhesion and cohesion
Thoughts on opportunities in high-energy nuclear collisions
This document reflects thoughts on opportunities from high-energy nuclear
collisions in the 2020s.Comment: 10 pages, pd
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
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