In situ microfluidic cryofixation for cryo Focused Ion Beam milling and cryo electron tomography.

We present a microfluidic platform for studying structure-function relationships at the cellular level by connecting video rate live cell imaging with in situ microfluidic cryofixation and cryo-electron tomography of near natively preserved, unstained specimens. Correlative light and electron microscopy (CLEM) has been limited by the time required to transfer live cells from the light microscope to dedicated cryofixation instruments, such as a plunge freezer or high-pressure freezer. We recently demonstrated a microfluidic based approach that enables sample cryofixation directly in the light microscope with millisecond time resolution, a speed improvement of up to three orders of magnitude. Here we show that this cryofixation method can be combined with cryo-electron tomography (cryo-ET) by using Focused Ion Beam milling at cryogenic temperatures (cryo-FIB) to prepare frozen hydrated electron transparent sections. To make cryo-FIB sectioning of rapidly frozen microfluidic channels achievable, we developed a sacrificial layer technique to fabricate microfluidic devices with a PDMS bottom wall <5 µm thick. We demonstrate the complete workflow by rapidly cryo-freezing Caenorhabditis elegans roundworms L1 larvae during live imaging in the light microscope, followed by cryo-FIB milling and lift out to produce thin, electron transparent sections for cryo-ET imaging. Cryo-ET analysis of initial results show that the structural preservation of the cryofixed C. elegans was suitable for high resolution cryo-ET work. The combination of cryofixation during live imaging enabled by microfluidic cryofixation with the molecular resolution capabilities of cryo-ET offers an exciting avenue to further advance space-time correlative light and electron microscopy (st-CLEM) for investigation of biological processes at high resolution in four dimensions

Documentation FiFoSiM: Integrated Tax Benefit Microsimulation and CGE Model

ABSTRACT: This paper describes FiFoSiM, the integrated tax benefit microsimulation and computable general equilibrium (CGE) model of the Center of Public Economics at the University of Cologne. FiFoSiM consists of three main parts. The first part is a static tax benefit microsimulation module. The second part adds a behavioural component to the model: an econometrically estimated labour supply model. The third module is a CGE model which allows the user of FiFoSiM to assess the global economic effects of policy measures. Two specific features distinguish FiFoSiM from other tax benefit models: First, the simultaneous use of two databases for the tax benefit module and second, the linkage of the tax benefit model to a CGE model

Drivers of Health Care Expenditure: Does Baumol's Cost Disease Loom Large?

According to Baumol (1993) health care epitomises Baumol's cost disease. Sectors that suffer from Baumol's cost disease are characterised by slow productivity growth due to a high labour coefficient. As a result, unit costs of these sectors rise inexorably if the respective wages increase with productivity growth of the progressive industries such as manufacturing. Thus, according to Baumol (1993) the secular rise in health-care expenditure has been unavoidable. This present paper demonstrates that health care is contracted by Baumol's cost disease, but only to a minor extent. Consequently, policy-makers have more leeway to curbever-increasing health-care expenditure than is suggested by Baumol (1993) and other authors. In addition, we test the implications of Baumol's cost disease for health care by avoiding the well-known flaws in constructing medical price indices. Therefore, the adjusted Baumol variable derived in this paper is also extremely appropriate to test the validity of Baumol's cost diseases of other service industries such as education or the live performing arts. Additionally, our analysis suggests that health care is rather a necessity than a luxury at the national level, which conflicts with macroeconomic evidence provided in the relevant literature

18 Billion at One Blow: Evaluating Germany's Twenty Biggest Tax Expenditures

“Periodically evaluating the size and effectiveness of tax expenditures is a necessary (although not sufficient) requirement for good government.” Leo Burman’s appeal of 2003 is quoted often but followed seldom. The paper reflects on the evaluation of Germany’s twenty biggest tax expenditures commissioned by the Federal Government in 2007 and completed by a team of three European research institutes in 2009. Based on a methodological framework developed for the uniform evaluation of dissimilar tax expenditures the research team worked through tax privileges worth more than 18 billion euro, i.e. 85 per cent of all official German tax subsidies. The analysis covered exemptions from corporate and personal income taxes, value-added tax (VAT) and energy taxes. To our knowledge, this was one of the biggest evaluations of tax expenditures ever concluded in the world. The paper discusses the common methodology applied in the evaluation; and the lessons learned from the research effort. It gives an overview of evaluation results and eventual policy lessons to be learned from them

Do higher corporate taxes reduce wages? : Micro evidence from Germany

Because of endogeneity problems very few studies have been able to identify the incidence of corporate taxes on wages. We circumvent these problems by using an 11-year panel of data on 11,441 German municipalities' tax rates, 8 percent of which change each year, linked to administrative matched employer-employee data. Consistent with our theoretical model, we find a negative effect of corporate taxation on wages: a 1 euro increase in tax liabilities yields a 77 cent decrease in the wage bill. The direct wage effect, arising in a collective bargaining context, dominates, while the conventional indirect wage effect through reduced investment is empirically small due to regional labor mobility. High and medium-skilled workers, who arguably extract higher rents in collective agreements, bear a larger share of the corporate tax burden

Measuring Distributional Effects of Fiscal Reforms

The purpose of this paper is to provide an overview of how to analyse the distributional effects of fiscal reforms. Thereby, distributional effects shall be differentiated by four subconcepts, i.e. 1.) the traditional concept of inequality, 2.) the rather novel concept of polarisation, 3.) the concept of progression in taxation, and 4.) the concepts of income poverty and richness. The concept of inequality and the concept of income poverty are the by far most widely applied concepts in empirical analyses, probably since they appear to be the most transparent ones in their structure as well as the most controversial ones in political affairs. However, the concepts of richness, polarisation and progression in taxation shall additionally be subject of this analysis, since they appear to be useful devices on the course of analysing cause and effect of the other two concepts

Cross-Border Group-Taxation and Loss-Offset in the EU - An Analysis for CCCTB (Common Consolidated Corporate Tax Base) and Etas (European Tax Allocation System)

The European Commission proposed to replace the currently existing Separate Accounting by an EU-wide tax system based on a Common Consolidated Corporate Tax Base (CCCTB). Besides the CCCTB, there is an alternative tax reform proposal, the European Tax Allocation System (ETAS). In a dynamic capital budgeting model we analyze the impacts of selected loss-offset limitations currently existing in the EU under both concepts on corporate crossborder real investments of MNE. The analyses show that replacing Separate Accounting by either concept can lead to increasing profitability due to cross-border loss compensation. However, if the profitability increases, the study indicates that the main criteria of decisions on location are the tax rate divergences within the EU Member States. High tax rate differentials in the Member States imply significant redistribution of tax payments under CCCTB and ETAS. The results clarify that in both reform proposals tax payment reallocations occur in favor of the holding. National loss-offset limitations and minimum taxation concepts in tendency lose their impact on the profitability under both proposals. However, we found scenarios in which national minimum taxation can encroach upon the group level, although in our model the minimum taxation's impacts seem to be slight. Moreover, we identify harmful paradoxes in ETAS due to the tax credit mechanism. Our results can contribute to the current discussion on corporate group tax harmonization within the EU and other economic zones, e.g. the US, and help to anticipate the tax effects of lossoffset restrictions under the respective tax systems