Output from an atom laser: theory vs. experiment

Atom lasers based on rf-outcoupling can be described by a set of coupled generalized Gross-Pitaevskii equations (GPE). We compare the theoretical predictions obtained by numerically integrating the time-dependent GPE of an effective one-dimensional model with recently measured experimental data for the F=2 and F=1 states of Rb-87. We conclude that the output of a rf-atom laser can be well described by this model.Comment: 4 pages, 5 figures, submitted to App. Phys.

Corruption and the shadow economy: An empirical analysis

This paper analyzes the influence of the shadow economy on corruption and vice versa. We hypothesize that corruption and shadow economy are substitutes in high income countries while they are complements in low income countries. The hypotheses are tested for a crosssection of 120 countries and a panel of 70 countries for the period 1994-2002. Our results show that the shadow economy reduces corruption in high income countries, but increases corruption in low income countries. We also find that stricter regulations increase both corruption and the shadow economy.corruption; shadow economy; regulation; tax burden

The Devil is in the Shadow: Do Institutions Affect Income and Productivity or Only Official Income and Official Productivity

This paper assesses the relationship between institutions, output, and productivity, when official output is corrected for the size of the shadow economy. Our results confirm the usual positive impact of institutional quality on official output and total factor productivity, and its negative impact on the size of the underground economy. However, once output is corrected for the shadow economy, the relationship between institutions and output becomes weaker. The impact of institutions on total (“corrected”) factor productivity even becomes insignificant. Differences in corrected output must then be attributed to differences in factor endowments. These results survive several tests for robustness

Reconciling history with the nation? Historicity, national particularity, and the question of universals

Chinese historiography and historical thinking in comparative perspectiv

The Devil is in the Shadow – Do Institutions Affect Income and Productivity or only Official Income and Official Productivity?

This paper assesses the relationship between institutions, output, and productivity, when official output is corrected for the size of the shadow economy. Our results confirm the usual positive impact of institutional quality on official output and total factor productivity, and its negative impact on the size of the underground economy. However, once output is corrected for the shadow economy, the relationship between institutions and output becomes weaker. The impact of institutions on total (“corrected”) factor productivity even becomes insignificant. Differences in corrected output must then be attributed to differences in factor endowments. These results survive several tests for robustness.shadow economy, income, aggregate productivity, development accounting

A genomic approach to examine the complex evolution of laurasiatherian mammals

Recent phylogenomic studies have failed to conclusively resolve certain branches of the placental mammalian tree, despite the evolutionary analysis of genomic data from 32 species. Previous analyses of single genes and retroposon insertion data yielded support for different phylogenetic scenarios for the most basal divergences. The results indicated that some mammalian divergences were best interpreted not as a single bifurcating tree, but as an evolutionary network. In these studies the relationships among some orders of the super-clade Laurasiatheria were poorly supported, albeit not studied in detail. Therefore, 4775 protein-coding genes (6,196,263 nucleotides) were collected and aligned in order to analyze the evolution of this clade. Additionally, over 200,000 introns were screened in silico, resulting in 32 phylogenetically informative long interspersed nuclear elements (LINE) insertion events. The present study shows that the genome evolution of Laurasiatheria may best be understood as an evolutionary network. Thus, contrary to the common expectation to resolve major evolutionary events as a bifurcating tree, genome analyses unveil complex speciation processes even in deep mammalian divergences. We exemplify this on a subset of 1159 suitable genes that have individual histories, most likely due to incomplete lineage sorting or introgression, processes that can make the genealogy of mammalian genomes complex. These unexpected results have major implications for the understanding of evolution in general, because the evolution of even some higher level taxa such as mammalian orders may sometimes not be interpreted as a simple bifurcating pattern

The Devil is in the Shadow Do institutions affect income and productivity or only official income and official productivity

This paper assesses the relationship between institutions, output, and productivity, when official output is corrected for the size of the shadow economy. Our results confirm the usual positive impact of institutional quality on official output and total factor productivity, and its negative impact on the size of the underground economy. However, once output is corrected for the shadow economy, the relationship between institutions and output becomes weaker. The impact of institutions on total (corrected) factor productivity even becomes insignificant. Differences in corrected output must then be attributed to differences in factor endowments. These results survive several tests for robustness. --shadow economy,income,aggregate productivity,development accounting