Palaeobiology of tanaidaceans (Crustacea: Peracarida) from Cretaceous ambers: extending the scarce fossil record of a diverse peracarid group.

Diverse assemblages of tanaidacean peracarid crustaceans from western Tethyan continental deposits suggest that the group was relatively common in or around ancient resin-producing forests. Here we report the results of an examination of 13 tanaidacean specimens from three Cretaceous (Albian to Turonian) French amber deposits. Two new species of the fossil family Alavatanaidae are placed in the previously described Early Cretaceous genus Eurotanais: Eurotanais pyrenaensissp. nov. from Cenomanian Pyrenean amber (Fourtou, Aude) and Eurotanais seilacherisp. nov. from Turonian Vendean amber (La Garnache, Vendée). The remaining specimens are placed in three newly erected genera and species (but family incertae sedis): Arcantitanais turpisgen. et sp. nov. from Albian-Cenomanian Charentese amber (Archingeay, Charente-Maritime), and Tytthotanais tenvisgen. et sp. nov. and Armadillopsis raragen. et sp. nov. from Pyrenean amber. These are the first formally described fossils that might be related to the paratanaoidean families Nototanaidae and Paratanaidae, sharing with these some putatively derived features and providing possible evidence for the antiquity and morphological stability of these families and the suborder Tanaidomorpha. The distinctive features and character combinations of these fossil taxa are discussed in connection with possible relationships to the living lineages of tanaidaceans. Propagation phase-contrast X-ray synchrotron microtomography was used to obtain high-quality 3D images for some fossils. A discussion is provided on the putative palaeobiology of tanaidaceans and the French resiniferous forest ecosystem. The discovery of these new tanaidaceans extends the palaeogeographical distribution and stratigraphical range of the family Alavatanaidae and sheds new light on the palaeoecology and diversity of tanaidaceans in pre-angiospermous woodlands

Probing Physics at Extreme Energies with Cosmic Ultra-High Energy Radiation

The highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic processes in the Universe. Their existence triggered a flurry of theoretical explanations ranging from conventional shock acceleration to particle physics beyond the Standard Model and processes taking place at the earliest moments of our Universe. Furthermore, many new experimental activities promise a strong increase of statistics at the highest energies and a combination with gamma-ray and neutrino astrophysics will put strong constraints on these theoretical models. We give an overview over this quickly evolving research field with focus on testing new particle physics.Comment: 12 latex pages, 2 postscript figures included; based on invited talk at the WHEPP-7 Conference, Allahabad, India (January, 2002

Evolutionary conserved NSL complex/BRD4 axis controls transcription activation via histone acetylation

Cells rely on a diverse repertoire of genes for maintaining homeostasis, but the transcriptional networks underlying their expression remain poorly understood. The MOF acetyltransferase-containing Non-Specific Lethal (NSL) complex is a broad transcription regulator. It is essential in Drosophila, and haploinsufficiency of the human KANSL1 subunit results in the Koolen-de Vries syndrome. Here, we perform a genome-wide RNAi screen and identify the BET protein BRD4 as an evolutionary conserved co-factor of the NSL complex. Using Drosophila and mouse embryonic stem cells, we characterise a recruitment hierarchy, where NSL-deposited histone acetylation enables BRD4 recruitment for transcription of constitutively active genes. Transcriptome analyses in Koolen-de Vries patient-derived fibroblasts reveals perturbations with a cellular homeostasis signature that are evoked by the NSL complex/BRD4 axis. We propose that BRD4 represents a conserved bridge between the NSL complex and transcription activation, and provide a new perspective in the understanding of their functions in healthy and diseased states

Income inequality and social gradients in children’s height: a comparison of cohort studies from five high-income countries

Background Health and well-being are better, on average, in countries that are more equal, but less is known about how this benefit is distributed across society. Height is a widely used, objective indicator of child health and predictor of lifelong well-being. We compared the level and slope of social gradients in children's height in high-income countries with different levels of income inequality, in order to investigate whether children growing up in all socioeconomic circumstances are healthier in more equal countries. Methods We conducted a coordinated analysis of data from five cohort studies from countries selected to represent different levels of income inequality (the USA, UK, Australia, the Netherlands and Sweden). We used standardised methods to compare social gradients in children's height at age 4-6 years, by parent education status and household income. We used linear regression models and predicted height for children with the same age, sex and socioeconomic circumstances in each cohort. Results The total analytic sample was 37 063 children aged 4-6 years. Gradients by parent education and household income varied between cohorts and outcomes. After adjusting for differences in age and sex, children in more equal countries (Sweden, the Netherlands) were taller at all levels of parent education and household income than children in less equal countries (USA, UK and Australia), with the greatest between-country differences among children with less educated parents and lowest household incomes. Conclusions The study provides preliminary evidence that children across society do better in more equal countries, with greatest benefit among children from the most disadvantaged socioeconomic groups

Taxing the Informal Economy: The Current State of Knowledge and Agendas for Future Research

This paper reviews the literature on taxation of the informal economy, taking stock of key debates and drawing attention to recent innovations. Conventionally, the debate on whether to tax has frequently focused on the limited revenue potential, high cost of collection, and potentially adverse impact on small firms. Recent arguments have increasingly emphasised the more indirect benefits of informal taxation in relation to economic growth, broader tax compliance, and governance. More research is needed, we argue, into the relevant costs and benefits for all, including quasi-voluntary compliance, political and administrative incentives for reform, and citizen-state bargaining over taxation

Grand Unification Signal from Ultra High Energy Cosmic Rays?

The spectrum of ultrahigh energy (above \approx 10^{9} GeV) cosmic rays is consistent with the decay of GUT scale particles. The predicted mass is m_X=10^b GeV, where b=14.6_{-1.7}^{+1.6}.Comment: 4 pages, 3 figures one figure removed, one table added, conclusions essentially remained the same within errorbar

Probing Grand Unified Theories with Cosmic Ray, Gamma-Ray and Neutrino Astrophysics

We explore scenarios where the highest energy cosmic rays are produced by new particle physics near the grand unification scale. Using detailed numerical simulations of extragalactic nucleon, gamma-ray, and neutrino propagation, we show the existence of an interesting parameter range for which such scenarios may explain part of the data and are consistent with all observational constraints. A combination of proposed observatories for ultra-high energy cosmic rays, neutrino telescopes of a few kilometer scale, and gamma-ray astrophysics instruments should be able to test these scenarios. In particular, for neutrino masses in the eV range, exclusive neutrino decay modes of superheavy particles can give rise to neutrino fluxes comparable to those predicted in models of active galactic nuclei.Comment: 15 latex pages, 5 postscript figures included, uses revtex.sty and psfig.sty. Submitted to Physical Review

Ultra High Energy Cosmic Rays from Cosmological Relics

The current status of origin of Ultra High Energy Cosmic Rays (UHECR) is reviewed, with emphasis given to elementary particle solutions to UHECR problem, namely to Topological Defects and Super-Heavy Dark Matter (SHDM) particles. The relic superheavy particles are very efficiently produced at inflation. Being protected by gauge discrete symmetries, they can be long lived. They are clustering in the Galactic halo, producing thus UHECR without Greisen-Zatsepin-Kuzmin cutoff. Topological Defects can naturally produce particles with energies as observed and much higher, but in most cases fail to produce the observed fluxes. Cosmic necklaces, monopoles connected by strings and vortons are identified as most plausible sources. The latter two of them are also clustering in the halo and their observational predictions are identical to those of SHDM particles.Comment: Invited talk at TAUP-99, Paris, September 6 - 10, 1999. Several references are adde