Indirect Taxation in Vertical Oligopoly

This paper analyzes the effects of specific and ad valorem taxation in an industry with downstream and upstream oligopoly. We find that in the short run, i.e. when the number of firms in both markets is exogenous, the results concerning tax incidence tend to be qualitatively similar to models where the upstream market is perfectly competitive. However, both over- and undershifting are more pronounced, potentially to a very large extent. Instead, in the long run under endogenous entry and exit overshifting of both taxes is more likely to occur and is more pronounced under upstream oligopoly. As a result of this, a tax increase is more likely to be welfare reducing. We also demonstrate that downstream and upstream taxation are equivalent in the short run while this is not true for the ad valorem tax in the long run. We show that it is normally more efficient to tax downstream

Indirect Taxation in Vertical Oligopoly

This paper analyzes the effects of specific and ad valorem taxation in an industry with downstream and upstream oligopoly. We find that in the short run, i.e. when the number of firms in both markets is exogenous, the results concerning tax incidence tend to be qualitatively similar to models where the upstream market is perfectly competitive. However, both over- and undershifting are more pronounced, potentially to a very large extent. Instead, in the long run under endogenous entry and exit overshifting of both taxes is more likely to occur and is more pronounced under upstream oligopoly. As a result of this, a tax increase is more likely to be welfare reducing. We also demonstrate that downstream and upstream taxation are equivalent in the short run while this is not true for the ad valorem tax in the long run. We show that it is normally more efficient to tax downstream.Specific Tax; Ad Valorem Tax; Value-Added Tax; Tax Incidence; Tax Efficiency; Indirect Taxation; Imperfect Competition; Vertical Oligopoly

Indirect Taxation in Vertical Oligopoly

This paper analyzes the effects of specific and ad valorem taxation in an industry with downstream and upstream oligopoly. We find that in the short run, i.e. when the number of firms in both markets is exogenous, the results concerning tax incidence tend to be qualitatively similar to models where the upstream market is perfectly competitive. However, both over- and undershifting are more pronounced, potentially to a very large extent. Instead, in the long run under endogenous entry and exit overshifting of both taxes is more likely to occur and is more pronounced under upstream oligopoly. As a result of this, a tax increase is more likely to be welfare reducing. We also demonstrate that downstream and upstream taxation are equivalent in the short run while this is not true for the ad valorem tax in the long run. We show that it is normally more efficient to tax downstream.specific tax, ad valorem tax, value-added tax, tax incidence, tax efficiency, indirect taxation, imperfect competition, vertical oligopoly

The Economics of Internet Media

We survey the economics literature on media as it applies to the Internet. The Internet is an important driver behind media convergence and connects information and communication technologies. While new Internet media share some properties with traditional media, several novel features have appeared: On the content side, aggregation by third parties that have no editorial policy and user-generated content have become increasingly important. On the advertiser side, fine-tuned tailoring and targeting of ads based on individual user characteristics are common features on many Internet media and social networks. On the user side, we observe increased possibilities of time-shifting, multi-homing, and active search. These changes have gone hand-in-hand with new players entering media markets, including search engines and Internet service providers. Some of these players face novel strategic considerations, such as how to present search results. In response to these changes, an emerging economics literature focuses on the allocative and welfare implications of this new media landscape. This paper is an attempt to organize these contributions and provide a selective account of novel economic mechanisms that shape market outcomes of Internet media. A large body of work has focused on the advertising part of the industry, while some studies also look at content provision and the interaction between the two

Invasive pulmonary aspergillosis complicating COVID-19 in the ICU - A case report.

It is not yet known, if critically ill COVID-19 patients are prone to fungal infections. We report a 69-year-old patient without typical risk factors for invasive pulmonary aspergillosis (IPA), who developed IPA two weeks after onset of symptoms. Our report shows that IPA may occur in critically ill COVID-19 patients

Segmentation versus agglomeration : competition between platforms with competitive sellers

For many products, platforms enable sellers to transact with buyers. We show that the competitive conditions among sellers shape the market structure in platform industries. If product market competition is tough, sellers avoid competitors by joining different platforms. This allows platforms to sustain high fees and explains why, for example, in some online markets, several homogeneous platforms segment the market. Instead, if product market competition is soft, agglomeration on a single platform emerges, and platforms fight for the dominant position. These insights give rise to novel predictions. For instance, market concentration and fees are negatively correlated in platform industries, which inverts the standard logic of competition

Fast resolution change in neutral helium atom microscopy

In neutral helium atom microscopy, a beam of atoms is scanned across a surface. Though still in its infancy, neutral helium microscopy has seen a rapid development over the last few years. The inertness and low energy of the helium atoms (less than 0.1 eV) combined with a very large depth of field and the fact that the helium atoms do not penetrate any solid material at low energies open the possibility for a non-destructive instrument that can measure topology on the nanoscale even on fragile and insulating surfaces. The resolution is determined by the beam spot size on the sample. Fast resolution change is an attractive property of a microscope because it allows different aspects of a sample to be investigated and makes it easier to identify specific features. However up till now it has not been possible to change the resolution of a helium microscope without breaking the vacuum and changing parts of the atom source. Here we present a modified source design, which allows fast, step wise resolution change. The basic design idea is to insert a moveable holder with a series of collimating apertures in front of the source, thus changing the effective source size of the beam and thereby the spot size on the surface and thus the microscope resolution. We demonstrate a design with 3 resolution steps. The number of resolution steps can easily be extended.publishedVersio

Epitaxy and magnetotransport of Sr_2FeMoO_6 thin films

By pulsed-laser deposition epitaxial thin films of Sr_2FeMoO_6 have been pre- pared on (100) SrTiO_3 substrates. Already for a deposition temperature of 320 C epitaxial growth is achieved. Depending on deposition parameters the films show metallic or semiconducting behavior. At high (low) deposition temperature the Fe,Mo sublattice has a rock-salt (random) structure. The metallic samples have a large negative magnetoresistance which peaks at the Curie temperature. The magnetic moment was determined to 4 mu_B per formula unit (f.u.), in agreement with the expected value for an ideal ferrimagnetic arrangement. We found an ordinary Hall coefficient of -6.01x10^{-10} m^3/As at 300 K, corresponding to an electronlike charge-carrier density of 1.3 per Fe,Mo-pair. In the semiconducting films the magnetic moment is reduced to 1 mu_B/f.u. due to disorder in the Fe,Mo sublattice. In low fields an anomalous holelike contribution dominates the Hall voltage, which vanishes at low temperatures for the metallic films only.Comment: Institute of Physics, University of Mainz, Germany, 4 pages, including 5 pictures and 1 Table, submitted to Phys. Rev.

Basic comparison of particle size distribution measurements of pigments and fillers using commonly available industrial methods

The Nanobiosciences Unit of the Joint Research Centre’s Institute for Health and Consumer Protection and Eurocolour, the association of European pigments, dyes and fillers industry, have carried out a program of work to evaluate a number of instrumental methods of measuring particle size distributions as required for assessing compliance versus the EU Recommendation for the definition on nanomaterials. The study has examined the use of five instrumental methods applied to a range of eight widely different but industrially relevant powder pigments. The techniques examined were Laser Diffraction (LD), Dynamic Light Scattering (DLS), Centrifugal Liquid Sedimentation (CLS), Volume Specific Surface Area (VSSA) and Electron Microscopy (EM). This report describes the materials studied and the preparative and analytical methods used. Individual chapters provide an overview of the single analytical methods used together with a summary of the results obtained using each particular method. In considering the results of this study it is important to note that the aim was not to determine the optimum conditions for every individual sample but rather to produce and evaluate data which could be considered representative of that obtainable in industrial laboratories using existing instrumental facilities operated by experienced but not specialised operators. The report discusses the challenges of using these instrumental methods to obtain a simple unambiguous classification of the test materials according to the EC definition.JRC.I.4-Nanobioscience

Effects of anti-resorptive treatment on the material properties of individual canine trabeculae in cyclic tensile tests

Osteoporosis is defined as a decrease of bone mass and strength, as well as an increase in fracture risk. It is conventionally treated with antiresorptive drugs, such as bisphosphonates (BPs) and selective estrogen receptor modulators (SERMs). Although both drug types successfully decrease the risk of bone fractures, their effect on bone mass and strength is different. For instance, BP treatment causes an increase of bone mass, stiffness and strength of whole bones, whereas SERM treatment causes only small (4%) increases of bone mass, but increased bone toughness. Such improved mechanical behavior of whole bones can be potentially related to the bone mass, bone structure or material changes. While bone mass and architecture have already been investigated previously, little is known about the mechanical behavior at the tissue/material level, especially of trabecular bone. As such, the goal of the work presented here was to fill this gap by performing cyclic tensile tests in a wet, close to physiologic environment of individual trabeculae retrieved from the vertebrae of beagle dogs treated with alendronate (a BP), raloxifene (a SERM) or without treatments. Identification of material properties was performed with a previously developed rheological model and of mechanical properties via fitting of envelope curves. Additionally, tissue mineral density (TMD) and microdamage formation were analyzed. Alendronate treatment resulted in a higher trabecular tissue stiffness and strength, associated with higher levels of TMD. In contrast, raloxifene treatment caused a higher trabecular toughness, pre-dominantly in the post-yield region. Microdamage formation during testing was not affected by either anti-resorptive treatment regimens. These findings highlight that the improved mechanical behavior of whole bones after anti-resorptive treatment is at least partly caused by improved material properties, with different mechanisms for alendronate and raloxifene. This study further shows the power of performing a mechanical characterization of trabecular bone at the level of individual trabeculae for better understanding of clinically relevant mechanical behavior of bone