Affinitätsmarkierung von Anionenkanälen und regulatorischen Proteinen im sarcoplasmatischen Reticulum

Die Vesikel des sarcoplasmatischen Reticulums (SR) der Skelettmuskulatur von Kaninchen enthalten neben Kanälen hoher (big chloride channel') und geringer (small chloride channel') Leitfähigkeit auch der äußeren Mitochondrienmembran bekannten voltage­dependent anion­selective channel' (VDAC). Der Kanal konnte mittels Immunodetektion Vesikeln heavy' und light' nachgewiesen, durch Affinitätschromatographie aufgereinigt nach der Spaltung Bromcyan teilsequenziert werden. Die Partialsequenzen beiden erhaltenen Fragmente stimmen Isoform 1 VDAC dem Cornea­Endothel Oryctolagus cuniculus (Kaninchen) sowie aus dem Mitochondrium überein. Jedoch weist Kanal unterschiedliche Eigenschaften auf. zeigt Gegensatz dem mitochondrialen VDAC keine Affinität dem Anionenkanal­Inhibitor SITS bildet SR­Membran keine Komplexe anderen Proteinen Bekannte Effektoren mitochondrialen VDAC wie NADH, DCCD anti­VDAC Antikörper zeigen Sulfat­Efflux­Experimenten entweder keine oder eine gegensätzliche Wirkung, was einen weiteren Hinweis unterschiedliche Regulationsfaktoren gibt. Die fehlenden Transporteigenschaften des rekonstituierten Kanals unter Sulfat­Efflux­ Bedingungen machen seine Beteiligung Sulfattransport und somit ­Transport SR sehr unwahrscheinlich. Vielmehr scheint den Transport von Nucleotiden, besonders ATP, SR­Lumen vermitteln. Allerdings weist auch hohe Affinitäten einem speziell synthetisierten GTP­Analogon auf könnte deshalb dem bekannten Eintransport von GTP in SR­Vesikel beteiligt sein. Nucleotide werden SR­Lumen Phos­ phorylierung verschiedener Proteine Sarcalumenin, HCP (histidine­rich protein') und Calsequestrin benötigt, neben ihrer Funktion ­Speicher auch der Regulation ­Release beteiligt sind. den Vesikeln sarcoplasmatischen Reticulums existieren mindestens zwei Proteine, durch Immunodetektion Affinitätsmarkierung mit einem radioaktiv markierten GTP­Analogon nachgewiesen wurden. greifen regulierend in den Anionentransport SR ein, Antikörper gegen G ­Untereinheit dieser Proteine den Sulfattransport hemmen. Diese Wirkung scheint allerdings direkt erfolgen nicht über second messenger'. Einen weiteren Hinweis G­Protein­vermittelte Regulation Anionentransports stellt sehr effiziente Hemmung des Sulfat­Efflux SR­Vesikeln durch Suramin verschiedene Arbeitskreis synthetisierte Suraminderivate Ein Analogon, spezifisch G­Protein­gekoppelten Ionenkanälen (P2Y ­ Purinoceptoren) Wechselwirkung und bindet eine alpha ­Untereinheit der SR­Vesikel. Ein weiteres Derivat, SB 22, zeigt ebenfalls Affinität zu dieser G alpha ­Untereinheit sowie zu einem anderen Protein (40 kDa) und der Ca ­ATPase. ­ATPase keine Transport­ eigenschaften für Sulfat aufweist, muß die hemmende Wirkung auf den Anionentransport entweder durch Modifikation einer Galpha ­Untereinheit oder Zeit noch nicht näher charakterisierten Proteins erfolgen. Der VDAC zeigt Suraminderivaten gegenüber inert und kommt deshalb nicht Sulfattransporter des sarcoplasmatischen Reticulums Frage

Når borger og kommune mødes digitalt

Citizens expect digital communication with public authorities to be as smooth as other online services. However, it is not easier to claim benefits and services only because it is done digitally. For municipalities and other public authorities, it is expensive when the citizens makes phone calls or show up at city hall, rather than using the online channels – and the municipalities experience budget reductions because of the savings digitization is meant to generate. The Municipality of Horsens have experienced success by, inspired by e-commerce, seeing digital self service as a product to be sold. The approach changes the rhetoric and language in the digital communication between citizen and public authority, and emphasizes the need for a holistic approach to digital self service. Different target groups present different challenges: the older generation may have difficulties in the digital interactions, whereas the younger age groups may have a hard time understanding certain key concepts in the language used by the municipality and other authorities

Vapor Pressures Of Some C4 Hydrocarbons And Their Mixtures

New experimental vapor pressures for the six binary systems containing 1,3-butadlene, n-butane, trans -2-butene, and c/s-2-butene at temperatures from 278 to 358 K are reported. Relative volatilities were calculated by using the Isothermal general coexistence equation. © 1982, American Chemical Society. All rights reserved

Stability of the viscously spreading ring

We study analytically and numerically the stability of the pressure-less, viscously spreading accretion ring. We show that the ring is unstable to small non-axisymmetric perturbations. To perform the perturbation analysis of the ring we use a stretching transformation of the time coordinate. We find that to 1st order, one-armed spiral structures, and to 2nd order additionally two-armed spiral features may appear. Furthermore, we identify a dispersion relation determining the instability of the ring. The theoretical results are confirmed in several simulations, using two different numerical methods. These computations prove independently the existence of a secular spiral instability driven by viscosity, which evolves into persisting leading and trailing spiral waves. Our results settle the question whether the spiral structures found in earlier simulations of the spreading ring are numerical artifacts or genuine instabilities.Comment: 13 pages, 12 figures; A&A accepte

An approach for solving the boundary free edge difficulties in SPH modelling: application to a viscous accretion disc in close binaries

In this work, we propose a SPH interpolating Kernel reformulation suitable also to treat free edge boundaries in the computational domain. Application to both inviscid and viscous stationary low compressibility accretion disc models in Close Binaries (CB) are shown. The investigation carried out in this paper is a consequence of the fact that a low compressibility modelling is crucial to check numerical reliability. Results show that physical viscosity supports a well-bound accretion disc formation, despite the low gas compressibility, when a Gaussian-derived Kernel (from the Error Function) is assumed, in extended particle range - whose Half Width at Half Maximum (HWHM) is fixed to a constant $h$ value - without any spatial restrictions on its radial interaction (hereinafter GASPHER). At the same time, GASPHER ensures adequate particle interpolations at the boundary free edges. Both SPH and adaptive SPH (hereinafter ASPH) methods lack accuracy if there are not constraints on the boundary conditions, in particular at the edge of the particle envelope: Free Edge (FE) conditions. In SPH, an inefficient particle interpolation involves a few neighbour particles; instead, in the second case, non-physical effects involve both the boundary layer particles themselves and the radial transport. Either in a regime where FE conditions involve the computational domain, or in a viscous fluid dynamics, or both, a GASPHER scheme can be rightly adopted in such troublesome physical regimes. Despite the applied low compressibiity condition, viscous GASPHER model shows clear spiral pattern profiles demonstrating the better quality of results compared to SPH viscous ones. Moreover a successful comparison of results concerning GASPHER 1D inviscid shock tube with analytical solution is also reported.Comment: 18 pages, 12 figure

Controlling Artificial Viscosity in SPH simulations of accretion disks

We test the operation of two methods for selective application of Artificial Viscosity (AV) in SPH simulations of Keplerian Accretion Disks, using a ring spreading test to quantify effective viscosity, and a correlation coefficient technique to measure the formation of unwanted prograde alignments of particles. Neither the Balsara Switch nor Time Dependent Viscosity work effectively, as they leave AV active in areas of smooth shearing flow, and do not eliminate the accumulation of alignments of particles in the prograde direction. The effect of both switches is periodic, the periodicity dependent on radius and unaffected by the density of particles. We demonstrate that a very simple algorithm activates AV only when truly convergent flow is detected and reduces the unwanted formation of prograde alignments. The new switch works by testing whether all the neighbours of a particle are in Keplerian orbit around the same point, rather than calculating the divergence of the velocity field, which is very strongly affected by Poisson noise in the positions of the SPH particles.Comment: 8 pages, 5 figure

O Instagram como ferramenta de distribuição da notícia : uma análise dos critérios de noticiabilidade da editoria de Política de GZH

Este trabalho busca compreender quais são os critérios de noticiabilidade mais utilizados e mais relevantes na hora de distribuir uma notícia de um site para a rede social, nesse caso, especificamente o Instagram. Para isso, foram analisadas 21 postagens no feed do perfil de GZH no Instagram, no período de um mês, do dia 8 de janeiro de 2023 a 8 de fevereiro de 2023, com foco na editoria de política. Além disso, para fins de comparação e determinação dos critérios que levam uma notícia do site para o Instagram, também foram consideradas as 607 notícias publicadas no site durante o mesmo período, dentro da mesma editoria. Diante desse estudo, foi possível determinar os 10 critérios de noticiabilidade mais relevantes nessa transição entre plataformas - do site para a rede social.This research seeks to understand which are the most used and most relevant newsworthiness criteria applied to move a post from the website to the profile on Instagram. With this purpose, 21 posts on the feed of GZH, on Instagram, were analyzed, between january 8th, 2023 to february 8th, 2023, inside the policy editorial. Besides that, for comparison, 607 posts of the website were analyzed during the same period and editorial. With that, it was possible to determine 10 newsworthiness criteria more relevant to the Instagram platform

An SPH multi-fluid model based on quasi-buoyancy for interface stabilization up to high density ratios and realistic wave speed ratios

We introduce a Smoothed Particle Hydrodynamics (SPH) concept for the stabilization of the interface between two fluids. It is demonstrated that the change in the pressure gradient across the interface leads to a force imbalance. This force imbalance is attributed to the particle approximation implicit to SPH. To stabilize the interface a pressure gradient correction is proposed. In this approach the multi-fluid pressure gradients are related to the (gravitational and fluid) accelerations. This leads to a quasi-buoyancy correction for hydrostatic (stratified) flows, which is extended to non-hydrostatic flows. The result is a simple density correction which involves no parameters or coefficients. This correction is included as an extra term in the SPH momentum equation. The new concept for the stabilization of the interface is explored in five case studies and compared with other multi-fluid models. The first case is the stagnant flow in a tank: the interface remains stable up to density ratios of 1:1000 (typical for water and air) in combination with artificial wave speed ratios up to 1:4. The second and third cases are the Rayleigh-Taylor instability and the rising bubble, where a reasonable agreement between SPH and level-set models is achieved. The fourth case is an air flow across a water surface up to density ratios of 1:100, artificial wave speeds for water higher than that of air, and high air velocities. The fifth case is about the propagation of internal gravity waves up to density ratios of 1:100 and artificial wave speed ratios of 1:2. It is demonstrated that the quasi-buoyancy model may be used to stabilize the interface between two fluids up to high density ratios, with real (low) viscosities and more realistic wave speed ratios than achieved by other WCSPH multi-fluid models. Real wave speed ratios can be achieved, as long as the fluid velocities are not very high. Although the wave speeds may be artificial in many cases, correct and realistic wave speed ratios are essential in the modelling of heat transfer between two fluids (e.g. in engineering applications such as gas turbines)