Change-over within little scope: On the decision neutrality of recent tax reform proposals

Political economy aspects make progressive income taxation and taxation of capital income imperative in practise. International tax competition and profit shifting, in turn, put pressure on corporate and capital taxes. Hence, the scope for a politically feasible change-over to a status of improved taxation is little. We provide an extended dynamic general equilibrium model and analyze politically feasible recent reform proposals referring neutrality. We then propose an alternative tax reform that, in contrast to these proposals, guarantees even growth neutrality, without necessarily jeopardizing political feasibility.Dynamic general equilibrium models; taxation; tax reform; decision neutrality; ACE; dual income tax

Properties of Foreshocks and Aftershocks of the Non-Conservative SOC Olami-Feder-Christensen Model: Triggered or Critical Earthquakes?

Following Hergarten and Neugebauer [2002] who discovered aftershock and foreshock sequences in the Olami-Feder-Christensen (OFC) discrete block-spring earthquake model, we investigate to what degree the simple toppling mechanism of this model is sufficient to account for the properties of earthquake clustering in time and space. Our main finding is that synthetic catalogs generated by the OFC model share practically all properties of real seismicity at a qualitative level, with however significant quantitative differences. We find that OFC catalogs can be in large part described by the concept of triggered seismicity but the properties of foreshocks depend on the mainshock magnitude, in qualitative agreement with the critical earthquake model and in disagreement with simple models of triggered seismicity such as the Epidemic Type Aftershock Sequence (ETAS) model [Ogata, 1988]. Many other features of OFC catalogs can be reproduced with the ETAS model with a weaker clustering than real seismicity, i.e. for a very small average number of triggered earthquakes of first generation per mother-earthquake.Comment: revtex, 19 pages, 8 eps figure

Das Übergangsmodell der Einfachsteuer: Eine Effiziente Unternehmensbesteuerung?

We investigate the neutrality features of an ACE tax reform proposal suggested for the company tax reform in Germany. As a pure ACE tax system is not feasible in practice, certain elements have been changed in the proposal: the traditional income tax of non-corporations remains progressive; there is a flat tax rate for corporations, but there is also a tax levied on distributed profits. Similar to S-corporations in the USA, both non-corporations and corporations (if feasible) have the option to be either taxed at the personal level of the owners within the income tax or at the company level within the profit tax (so far corporate tax). In both cases, the companies have a claim on a operating expenditure for equity cost (ACE). To analyze the proposal we extend the neoclassical model by allowing for financial assets of companies. The proposal causes that investors distinguish two rates of discounting. Therefore, as we want to determine the optimal level of investment endogenously, we cannot maximize the market value of the company. The problem can be solved by maximizing the end value of the investments. We show that the proposed tax system guarantees financial, investment, legal form, and depreciation neutrality. Intertemporal or growth neutrality, however, is only generated financing investments by retaining profits

Das Übergangsmodell der Einfachsteuer: Eine Effiziente Unternehmensbesteuerung?

We investigate the neutrality features of an ACE tax reform proposal suggested for the company tax reform in Germany. As a pure ACE tax system is not feasible in practice, certain elements have been changed in the proposal: the traditional income tax of non-corporations remains progressive; there is a flat tax rate for corporations, but there is also a tax levied on distributed profits. Similar to S-corporations in the USA, both non-corporations and corporations (if feasible) have the option to be either taxed at the personal level of the owners within the income tax or at the company level within the profit tax (so far corporate tax). In both cases, the companies have a claim on a operating expenditure for equity cost (ACE). To analyze the proposal we extend the neoclassical model by allowing for financial assets of companies. The proposal causes that investors distinguish two rates of discounting. Therefore, as we want to determine the optimal level of investment endogenously, we cannot maximize the market value of the company. The problem can be solved by maximizing the end value of the investments. We show that the proposed tax system guarantees financial, investment, legal form, and depreciation neutrality. Intertemporal or growth neutrality, however, is only generated financing investments by retaining profits

Change-over within little scope: On the decision neutrality of recent tax reform proposals

Political economy aspects make progressive income taxation and taxation of capital income imperative in practise. International tax competition and profit shifting, in turn, put pressure on corporate and capital taxes. Hence, the scope for a politically feasible change-over to a status of improved taxation is little. We provide an extended dynamic general equilibrium model and analyze politically feasible recent reform proposals referring neutrality. We then propose an alternative tax reform that, in contrast to these proposals, guarantees even growth neutrality, without necessarily jeopardizing political feasibility

Solar and Atmospheric Neutrinos: Background Sources for the Direct Dark Matter Searches

In experiments for direct dark matter searches, neutrinos coherently scattering off nuclei can produce similar events as Weakly Interacting Massive Particles (WIMPs). The calculated count rate for solar neutrinos in such experiments is a few events per ton-year. This count rate strongly depends on the nuclear recoil energy threshold achieved in the experiments for the WIMP search. We show that solar neutrinos can be a serious background source for direct dark matter search experiments using Ge, Ar, Xe and CaWO_4 as target materials. To reach sensitivities better than approximatly 10^-10 pb for the elastic WIMP nucleon spin-independent cross section in the zero-background limit, energy thresholds for nuclear recoils should be approximatly >2.05 keV for CaWO_4, >4.91 keV for Ge, >2.89 keV for Xe, and >8.62 keV for Ar as target material. Next-generation experiments should not only strive for a reduction of the present energy thresholds but mainly focus on an increase of the target mass. Atmospheric neutrinos limit the achievable sensitivity for the background-free direct dark matter search to approximatly >10^-12 pb.Comment: accepted by Astroparticle Physic

Ligand binding and conformational dynamics of the E. coli nicotinamide nucleotide transhydrogenase revealed by hydrogen/deuterium exchange mass spectrometry

Nicotinamide nucleotide transhydrogenases are integral membrane proteins that utilizes the proton motive force to reduce NADP+ to NADPH while converting NADH to NAD+. Atomic structures of various transhydrogenases in different ligand-bound states have become available, and it is clear that the molecular mechanism involves major conformational changes. Here we utilized hydrogen/deuterium exchange mass spectrometry (HDX-MS) to map ligand binding sites and analyzed the structural dynamics of E. coli transhydrogenase. We found different allosteric effects on the protein depending on the bound ligand (NAD+, NADH, NADP+, NADPH). The binding of either NADP+ or NADPH to domain III had pronounced effects on the transmembrane helices comprising the proton-conducting channel in domain II. We also made use of cyclic ion mobility separation mass spectrometry (cyclic IMS-MS) to maximize coverage and sensitivity in the transmembrane domain, showing for the first time that this technique can be used for HDX-MS studies. Using cyclic IMS-MS, we increased sequence coverage from 68 % to 73 % in the transmembrane segments. Taken together, our results provide important new insights into the transhydrogenase reaction cycle and demonstrate the benefit of this new technique for HDX-MS to study ligand binding and conformational dynamics in membrane proteins