Nutzen und Kosten eines Austritts Griechenlands aus dem Euro

Die klassischen, seit Jahrhunderten erprobten Instrumente zur Bewältigung von Staatsbankrotten sind Umschuldung und nachfolgende Abwertung. Charles B. Blankart und Sven Bretschneider, Humboldt-Universität zu Berlin, gehen von einem weiteren Schritt aus: Nach der Umschuldung sei ein Austritt erforderlich, um zur Abwertung zu gelangen. Darin liege aber auch das Problem. Vor einem Austritt schrecken die meisten Europolitiker zurück. In ihrem Kommentar wägen Blankart und Bretschneider in einer Nutzen-Kosten-Analyse ab, was für die Euro-Union besser ist: der Austritt oder ein »Weiter so wie bisher«

The Second Transmembrane Domain of P2X7 Contributes to Dilated Pore Formation

Activation of the purinergic receptor P2X7 leads to the cellular permeability of low molecular weight cations. To determine which domains of P2X7 are necessary for this permeability, we exchanged either the C-terminus or portions of the second transmembrane domain (TM2) with those in P2X1 or P2X4. Replacement of the C-terminus of P2X7 with either P2X1 or P2X4 prevented surface expression of the chimeric receptor. Similarly, chimeric P2X7 containing TM2 from P2X1 or P2X4 had reduced surface expression and no permeability to cationic dyes. Exchanging the N-terminal 10 residues or C-terminal 14 residues of the P2X7 TM2 with the corresponding region of P2X1 TM2 partially restored surface expression and limited pore permeability. To further probe TM2 structure, we replaced single residues in P2X7 TM2 with those in P2X1 or P2X4. We identified multiple substitutions that drastically changed pore permeability without altering surface expression. Three substitutions (Q332P, Y336T, and Y343L) individually reduced pore formation as indicated by decreased dye uptake and also reduced membrane blebbing in response to ATP exposure. Three others substitutions, V335T, S342G, and S342A each enhanced dye uptake, membrane blebbing and cell death. Our results demonstrate a critical role for the TM2 domain of P2X7 in receptor function, and provide a structural basis for differences between purinergic receptors. © 2013 Sun et al

Spatial distribution and variability of boundary layer aerosol particles observed in Ny-Ålesund during late spring in 2018

This article aims to improve the understanding of the small-scale aerosol distribution affected by different atmospheric boundary layer (ABL) properties. In particular, transport and mixing of ultrafine aerosol particles (UFPs) are investigated as an indicator for possible sources triggering the appearance of new particle formation (NPF) at an Arctic coastal site. For this purpose, flexible measurements of uncrewed aerial systems (UASs) are combined with continuous ground-based observations at different altitudes, the Gruvebadet observatory close to the fjord at an altitude of 67 m above sea level (a.s.l.) and the observatory at Mount Zeppelin at an altitude of 472 m a.s.l. The two uncrewed research aircraft called ALADINA and MASC-3 were used for field activities at the polar research site Ny-Ålesund, Svalbard, between 24 April and 25 May 2018. The period was at the end of Arctic haze during the snowmelt season. A high frequency of occurrence of UFPs was observed, namely on 55 % of the airborne measurement days. With ALADINA, 230 vertical profiles were performed between the surface and the main typical maximum height of 850 m a.s.l., and the profiles were connected to surface measurements in order to obtain a 4-D picture of the aerosol particle distribution. Analyses of potential temperature, water vapor mixing ratio and aerosol particle number concentration of UFPs in the size range of 3–12 nm (N3−12) indicate a clear impact of the ABL's stability on the vertical mixing of the measured UFPs, which results in systematical differences of particle number concentrations at the two observatories. In general, higher concentrations of UFPs occurred near the surface, suggesting the open sea as the main source for NPF. Three different case studies show that the UFPs were rapidly mixed in the vertical and horizontal scale depending on atmospheric properties. In case of temperature inversions, the aerosol population remained confined to specific altitude ranges and was not always detected at the observatories. However, during another case study that was in relation to a persistent NPF event with subsequent growth rate, the occurrence of UFPs was identified to be a wide-spreading phenomenon in the vertical scale, as the observed UFPs exceeded the height of 850 m a.s.l. During a day with increased local pollution, enhanced equivalent black carbon mass concentration (eBC) coincided with an increase in the measured N3−12 in the lowermost 400 m but without subsequent growth rate. The local pollution was transported to higher altitudes, as measured by ALADINA. Thus, emissions from local pollution may play a role for potential sources of UFPs in the Arctic as well. In summary, a highly variable spatial and temporal aerosol distribution was observed with small scales at the polar site Ny-Ålesund, determined by atmospheric stability, contrasting surface and sources, and topographic flow effects. The UAS provides the link to understand differences measured at the two observatories at close distances but different altitudes.</p

Marketing madness or financial folly?: Implementing equity crowdfunding in the record industry

Purpose The purpose of this paper is to explore the implementation of equity crowdfunding (ECF) within the record industry in terms of challenges and opportunities, in addition to the marketing and financial implications for independent music artists and major record labels. Design/methodology/approach This study adopted a qualitative methodology consisting of two-stage interview-based research methods. A total of 44 semi-structured in-depth interviews were conducted with the CEOs of ECF platforms in the record industry, other related record industry informants, independent artist managers and senior executives from major record labels. Findings The loyalty aspect of ECF may have significant marketing potential in terms of inconspicuously using the equity platform as a “prosumer” identification mechanism. As this early career stage of artists is delicate in terms of establishing trust and patronage from their fans, these early marketing and ECF ventures should be implemented directly from the artist without external third-party involvement. Research limitations/implications The implications of this paper’s findings and theoretical model are not limited to the two studied stakeholder groups of the record industry. The insights in relation to the obstinate lack of understanding and clarity (particularly for independent artists) which surround ECF are likely to influence short-term strategic approaches by other players throughout the wider music industry. Practical implications The insights regarding negative approaches towards ECF by the labels may influence future “coopetition strategies” for independent labels, as they seek to navigate the changing industry dynamics. Originality/value This paper is the first study to empirically explore the predominantly under-researched area of ECF implementation in the record industry in terms of marketing and financial consequences for artists and labels. </jats:sec

Self-organizing actin waves that simulate phagocytic cup structures

This report deals with actin waves that are spontaneously generated on the planar, substrate-attached surface of Dictyostelium cells. These waves have the following characteristics. (1) They are circular structures of varying shape, capable of changing the direction of propagation. (2) The waves propagate by treadmilling with a recovery of actin incorporation after photobleaching of less than 10 seconds. (3) The waves are associated with actin-binding proteins in an ordered 3-dimensional organization: with myosin-IB at the front and close to the membrane, the Arp2/3 complex throughout the wave, and coronin at the cytoplasmic face and back of the wave. Coronin is a marker of disassembling actin structures. (4) The waves separate two areas of the cell cortex that differ in actin structure and phosphoinositide composition of the membrane. The waves arise at the border of membrane areas rich in phosphatidylinositol (3,4,5) trisphosphate (PIP3). The inhibition of PIP3 synthesis reversibly inhibits wave formation. (5) The actin wave and PIP3 patterns resemble 2-dimensional projections of phagocytic cups, suggesting that they are involved in the scanning of surfaces for particles to be taken up

Bistability in the actin cortex

Multi-color fluorescence imaging experiments of wave forming Dictyostelium cells have revealed that actin waves separate two domains of the cell cortex that differ in their actin structure and phosphoinositide composition. We propose a bistable model of actin dynamics to account for these experimental observation. The model is based on the simplifying assumption that the actin cytoskeleton is composed of two distinct network types, a dendritic and a bundled network. The two structurally different states that were observed in experiments correspond to the stable fixed points in the bistable regime of this model. Each fixed point is dominated by one of the two network types. The experimentally observed actin waves can be considered as trigger waves that propagate transitions between the two stable fixed points

Identification of epitopes recognised by mucosal CD4+ T-cell populations from cattle experimentally colonised with Escherichia coli O157:H7

Additional file 5. Sequence alignment of Intimin epitopes against Intimin sequences from non-O157 EHEC serotypes. Alignment of Intimin CD4+ T-cell epitope sequences with representative Intimin sequences from EHEC serotypes O145, O127, O26, O103, O121, O45 and O111. Percentage values indicate % similarity to the EHEC O157:H7 reference sequence

Improving the Health of Older Prisoners: Nutrition and Exercise in Correctional Institutions

This qualitative article presents and compares the views of older prisoners and expert stakeholders on the topic of nutrition and exercise. The study highlights measures for improving the health of older prisoners. Older prisoners report the need to improve quality of meals provided in prison. They note that prison food is of poor quality and not adapted to their needs. With regard to exercise, they point out the lack of proper opportunities to engage in exercise and sports, and describe several factors that make physical activities either unsuitable or unfeasible. Expert stakeholders see prison as an opportunity to improve the health of those convicted of crimes. In light of the increasing number of older prisoners, age-appropriate nutritional and exercise interventions should take priority in prisons

Comparison between a linear versus a macrocyclic contrast agent for whole body MR angiography in a clinical routine setting

<p>Abstract</p> <p>Background</p> <p>Previous experiences of whole body MR angiography are predominantly available in linear 0.5 M gadolinium-containing contrast agents. The aim of this study was to compare image quality on a four-point scale (range 1–4) and diagnostic accuracy of a 1.0 M macrocyclic contrast agent (gadobutrol, n = 80 patients) with a 0.5 M linear contrast agent (gadopentetate dimeglumine, n = 85 patients) on a 1.5 T whole body MR system. Digital subtraction angiography served as standard of reference.</p> <p>Results</p> <p>All examinations yielded diagnostic image quality. There was no significant difference in image quality (3.76 ± 0.3 versus 3.78 ± 0.3, p = n.s.) and diagnostic accuracy observed. Sensitivity and specificity of the detection of hemodynamically relevant stenoses was 93%/95% in the gadopentetate dimeglumine group and 94%/94% in the gadobutrol group, respectively.</p> <p>Conclusion</p> <p>The high diagnostic accuracy of gadobutrol in the clinical routine setting is of high interest as medical authorities (e.g. the European Agency for the Evaluation of Medicinal Products) recommend macrocyclic contrast agents especially to be used in patients with renal failure or dialysis.</p

Keep them alive! Design and Evaluation of the “Community Fostering Reference Model”

Firms host online communities for commercial purposes, for example in order to integrate customers into ideation for new product development. The success of these firm-hosted online communities depends entirely on the cooperation of a high number of customers that constantly produce valuable knowledge for firms. However, in practice, the majority of successfully implemented communities suffers from stagnation and even a decrease of member activities over time. Literature provides numerous guidelines on how to build and launch these online communities. While these models describe the initial steps of acquiring and activating a community base from scratch very well and explicitly, they neglect continuous member activation and acquistion after a successful launch. Against this background, the authors propose the Community Fostering Reference Model (CoFoRM), which represents a set of general procedures and instruments to continuously foster member activity. In this paper, the authors present the theory-driven design as well as the evaluation of the CoFoRM in a practical use setting. The evaluation results reveal that the CoFoRM represents a valuable instrument in the daily working routine of community managers, since it efficiently helps activating community members especially in the late phases of a community’s LifeCycle