Besteuerungsprinzipien und effektive Unternehmenssteuerbelastungen in der Europäischen Union

Dieser Beitrag untersucht umfassend die Unternehmensbesteuerung in der Europäischen Union im Zeitraum von 1998 bis 2007. Das innereuropäische Steuergefälle wird unter Rückgriff auf zwei zentrale Maßgrößen - die Kapitalkosten und die effektive Durchschnittssteuerbelastung - abgebildet. Die Berechnungen auf Grundlage der Methodik nach Devereux und Griffith erlauben dabei die Messung der Steuerbelastung auf rein inländische als auch auf grenzüberschreitende (Direkt-)Investitionen. Die eingehende Analyse der auf diese Weise detailliert quantifizierten Besteuerungsregime zeigt unter anderem, dass in der EU das Prinzip der Kapitalimportneutralität gegenüber einer Verwirklichung von Kapitalexportneutralität klar dominiert. Die nicht realisierte Harmonisierung der Unternehmensbesteuerung impliziert Produktionsineffizienzen aufgrund steuerlich verzerrter Investitions- und Standortentscheidungen sowie Wettbewerbsverzerrungen

Peptide-based solutions to reduce undesired cell culture media chemistry – New options for stabilized media formulations

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Besteuerungsprinzipien und effektive Unternehmenssteuerbelastungen in der Europäischen Union

Dieser Beitrag untersucht umfassend die Unternehmensbesteuerung in der Europäischen Union im Zeitraum von 1998 bis 2007. Das innereuropäische Steuergefälle wird unter Rückgriff auf zwei zentrale Maßgrößen - die Kapitalkosten und die effektive Durchschnittssteuerbelastung - abgebildet. Die Berechnungen auf Grundlage der Methodik nach Devereux und Griffith erlauben dabei die Messung der Steuerbelastung auf rein inländische als auch auf grenzüberschreitende (Direkt-)Investitionen. Die eingehende Analyse der auf diese Weise detailliert quantifizierten Besteuerungsregime zeigt unter anderem, dass in der EU das Prinzip der Kapitalimportneutralität gegenüber einer Verwirklichung von Kapitalexportneutralität klar dominiert. Die nicht realisierte Harmonisierung der Unternehmensbesteuerung impliziert Produktionsineffizienzen aufgrund steuerlich verzerrter Investitions- und Standortentscheidungen sowie Wettbewerbsverzerrungen. --Effektive Steuerbelastung,Europäische Union,Unternehmensbesteuerung

Warum so garstig? Zum Einfluss von realweltlichen, medien- und diskussionsimmanenten sowie situativen Faktoren auf die (In)Zivilität von Onlinediskussionen

Der vorliegende Beitrag beschäftigt sich mit der Frage, welche Faktoren das Ausmaß von Inzivilität und argumentativer Qualität in Nutzerkommentaren beeinflussen. Kognitives und affektives Involvement werden als zentrale Triebfedern für das Verfassen von Nutzerkommentaren identifiziert. Wir vermuten, dass realweltliche, medien- und diskussionsimmanenten sowie situative Faktoren das Ausmaß kognitiven sowie affektiven Involvements und darüber vermittelt auch das Kommentierverhalten beeinflussen. In einer Inhaltsanalyse von Nutzerkommentaren unter Onlineartikeln zu Tarifkonflikten auf bild.de und spiegel.de aus dem Jahr 2015 untersuchen wir den relativen Einfluss der verschiedenen Faktoren auf das Ausmaß an Inzivilität und argumentativer Qualität in Onlinediskussionen. Insbesondere die situativen Faktoren entscheiden darüber, inwieweit Nutzende inzivil oder diskursiv kommentiert. Allerdings schließen sich Inzivilität und argumentative Qualität keineswegs aus

Autofluorescent granules of the human retinal pigment epithelium: phenotypes, intracellular distribution, and age-related topography

PURPOSE. The human retinal pigment epithelium (RPE) accumulates granules significant for autofluorescence imaging. Knowledge of intracellular accumulation and distribution is limited. Using high-resolution microscopy techniques, we determined the total number of granules per cell, intracellular distribution, and changes related to retinal topography and age. METHODS. RPE cells from the fovea, perifovea, and near-periphery of 15 human RPE flat mounts were imaged using structured illumination microscopy (SIM) and confocal fluorescence microscopy in young (=51 years, n = 8) and older (>80 years, n = 7) donors. Using custom FIJI plugins, granules were marked with computer assistance, classified based on morphological and autofluorescence properties, and analyzed with regard to intracellular distribution, total number per cell, and granule density. RESULTS. A total of 193,096 granules in 450 RPE cell bodies were analyzed. Based on autofluorescence properties, size, and composition, the RPE granules exhibited nine different phenotypes (lipofuscin, two; melanolipofuscin, five; melanosomes, two), distinguishable by SIM. Overall, lipofuscin (low at the fovea but increases with eccentricity and age) and melanolipofuscin (equally distributed at all three locations with no age-related changes) were the major granule types. Melanosomes were under-represented due to suboptimal visualization of apical processes in flat mounts. CONCLUSIONS. Low lipofuscin and high melanolipofuscin content within foveal RPE cell bodies and abundant lipofuscin at the perifovea suggest a different genesis, plausibly related to the population of overlying photoreceptors (fovea, cones only; perifovea, highest rod density). This systematic analysis provides further insight into RPE cell and granule physiology and links granule load to cell autofluorescence, providing a subcellular basis for the interpretation of clinical fundus autofluorescence. © 2020 Association for Research in Vision and Ophthalmology Inc.. All rights reserved

A new method to quantify mineral dust and other aerosol species from aircraft platforms using single particle mass spectrometry

Single-particle mass spectrometry (SPMS) instruments characterize the composition of individual aerosol particles in real time. Their fundamental ability to differentiate the externally mixed particle types that constitute the atmospheric aerosol population enables a unique perspective into sources and transformation. However, quantitative measurements by SPMS systems are inherently problematic. We introduce a new technique that combines collocated measurements of aerosol composition by SPMS and size-resolved absolute particle concentrations on aircraft platforms. Quantitative number, surface area, volume, and mass concentrations are derived for climate-relevant particle types such as mineral dust, sea salt, and biomass burning smoke. Additionally, relative ion signals are calibrated to derive mass concentrations of internally mixed sulfate and organic material that are distributed across multiple particle types. The NOAA Particle Analysis by Laser Mass Spectrometry (PALMS) instrument measures size-resolved aerosol chemical composition from aircraft. We describe the identification and quantification of nine major atmospheric particle classes, including sulfate–organic–nitrate mixtures, biomass burning, elemental carbon, sea salt, mineral dust, meteoric material, alkali salts, heavy fuel oil combustion, and a remainder class. Classes can be sub-divided as necessary based on chemical heterogeneity, accumulated secondary material during aging, or other atmospheric processing. Concentrations are derived for sizes that encompass the accumulation and coarse size modes. A statistical error analysis indicates that particle class concentrations can be determined within a few minutes for abundances above ∼10 ng m−3. Rare particle types require longer sampling times. We explore the instrumentation requirements and the limitations of the method for airborne measurements. Reducing the size resolution of the particle data increases time resolution with only a modest increase in uncertainty. The principal limiting factor to fast time response concentration measurements is statistically relevant sampling across the size range of interest, in particular, sizes D \u3c 0.2 µm for accumulation-mode studies and D \u3e 2 µm for coarse-mode analysis. Performance is compared to other airborne and ground-based composition measurements, and examples of atmospheric mineral dust concentrations are given. The wealth of information afforded by composition-resolved size distributions for all major aerosol types represents a new and powerful tool to characterize atmospheric aerosol properties in a quantitative fashion

PIP5KIβ Selectively Modulates Apical Endocytosis in Polarized Renal Epithelial Cells

Localized synthesis of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] at clathrin coated pits (CCPs) is crucial for the recruitment of adaptors and other components of the internalization machinery, as well as for regulating actin dynamics during endocytosis. PtdIns(4,5)P2 is synthesized from phosphatidylinositol 4-phosphate by any of three phosphatidylinositol 5-kinase type I (PIP5KI) isoforms (α, β or γ). PIP5KIβ localizes almost exclusively to the apical surface in polarized mouse cortical collecting duct cells, whereas the other isoforms have a less polarized membrane distribution. We therefore investigated the role of PIP5KI isoforms in endocytosis at the apical and basolateral domains. Endocytosis at the apical surface is known to occur more slowly than at the basolateral surface. Apical endocytosis was selectively stimulated by overexpression of PIP5KIβ whereas the other isoforms had no effect on either apical or basolateral internalization. We found no difference in the affinity for PtdIns(4,5)P2-containing liposomes of the PtdIns(4,5)P2 binding domains of epsin and Dab2, consistent with a generic effect of elevated PtdIns(4,5)P2 on apical endocytosis. Additionally, using apical total internal reflection fluorescence imaging and electron microscopy we found that cells overexpressing PIP5KIβ have fewer apical CCPs but more internalized coated structures than control cells, consistent with enhanced maturation of apical CCPs. Together, our results suggest that synthesis of PtdIns(4,5)P2 mediated by PIP5KIβ is rate limiting for apical but not basolateral endocytosis in polarized kidney cells. PtdIns(4,5)P2 may be required to overcome specific structural constraints that limit the efficiency of apical endocytosis. © 2013 Szalinski et al

Ambient aerosol properties in the remote atmosphere from global-scale in-situ measurements

In situ measurements of aerosol microphysical, chemical, and optical properties were made during global-scale flights from 2016–2018 as part of the Atmospheric Tomography Mission (ATom). The NASA DC-8 aircraft flew from ∼ 84∘ N to ∼ 86∘ S latitude over the Pacific, Atlantic, Arctic, and Southern oceans while profiling nearly continuously between altitudes of ∼ 160 m and ∼ 12 km. These global circuits were made once each season. Particle size distributions measured in the aircraft cabin at dry conditions and with an underwing probe at ambient conditions were combined with bulk and single-particle composition observations and measurements of water vapor, pressure, and temperature to estimate aerosol hygroscopicity and hygroscopic growth factors and calculate size distributions at ambient relative humidity. These reconstructed, composition-resolved ambient size distributions were used to estimate intensive and extensive aerosol properties, including single-scatter albedo, the asymmetry parameter, extinction, absorption, Ångström exponents, and aerosol optical depth (AOD) at several wavelengths, as well as cloud condensation nuclei (CCN) concentrations at fixed supersaturations and lognormal fits to four modes. Dry extinction and absorption were compared with direct in situ measurements, and AOD derived from the extinction profiles was compared with remotely sensed AOD measurements from the ground-based Aerosol Robotic Network (AERONET); this comparison showed no substantial bias. The purpose of this work is to describe the methodology by which ambient aerosol properties are estimated from the in situ measurements, provide statistical descriptions of the aerosol characteristics of different remote air mass types, examine the contributions to AOD from different aerosol types in different air masses, and provide an entry point to the ATom aerosol database. The contributions of different aerosol types (dust, sea salt, biomass burning, etc.) to AOD generally align with expectations based on location of the profiles relative to continental sources of aerosols, with sea salt and aerosol water dominating the column extinction in most remote environments and dust and biomass burning (BB) particles contributing substantially to AOD, especially downwind of the African continent. Contributions of dust and BB aerosols to AOD were also significant in the free troposphere over the North Pacific. Comparisons of lognormally fitted size distribution parameters to values in the Optical Properties of Aerosols and Clouds (OPAC) database commonly used in global models show significant differences in the mean diameters and standard deviations for accumulation-mode particles and coarse-mode dust. In contrast, comparisons of lognormal parameters derived from the ATom data with previously published shipborne measurements in the remote marine boundary layer show general agreement. The dataset resulting from this work can be used to improve global-scale representation of climate-relevant aerosol properties in remote air masses through comparison with output from global models and assumptions used in retrievals of aerosol properties from both ground-based and satellite remote sensing