Deployment of Mobile Broadband Service in the United States

Broadband deployment in the United States is expanding rapidly but unevenly. Using new FCC census data on wireline and wireless broadband providers, we study mobile broadband provision within the United States. Although rural areas lag non-rural areas in the availability of residential access to both mobile and fixed broadband, mobile broadband is at least partially filling in geographical gaps in fixed-line broadband coverage. Multiple regression results indicate that population density and growth, and the fraction of blacks, Hispanics, and youth in an area are positive predictors of the number of mobile broadband providers. The fraction of Native Americans, Asians, and senior citizens in an area are negative predictors. Income is positively associated with the number of providers, with largest effects in rural areas. Finally, even after controlling for population density and income, rural areas continue to be associated with a lower number of providers

Puffins, Pigs, Cod, and Barley: Palaeoeconomy at Undir Junkarinsfløtti, Sandoy, Faroe Islands

This paper reports on the zooarchaeological and archaeobotanical remains from the initial season of excavations at the Norse period site at Undir Junkarinsfløtti in the Faroe islands. These remains represent the first zooarchaeological analysis undertaken for the Faroes and only the third archaeobotanical assemblage published from the islands. The excavated deposits are described and the key findings from the palaeoenvironmental remains highlighted within the context of the wider North Atlantic environmental archaeology of the Norse period

Puffins, Pigs, Cod, and Barley: Palaeoeconomy at Undir Junkarinsfløtti, Sandoy, Faroe Islands

This paper reports on the zooarchaeological and archaeobotanical remains from the initial season of excavations at the Norse period site at Undir Junkarinsfløtti in the Faroe islands. These remains represent the first zooarchaeological analysis undertaken for the Faroes and only the third archaeobotanical assemblage published from the islands. The excavated deposits are described and the key findings from the palaeoenvironmental remains highlighted within the context of the wider North Atlantic environmental archaeology of the Norse period

Improved annotation of 3' untranslated regions and complex loci by combination of strand-specific direct RNA sequencing, RNA-seq and ESTs

The reference annotations made for a genome sequence provide the framework for all subsequent analyses of the genome. Correct annotation is particularly important when interpreting the results of RNA-seq experiments where short sequence reads are mapped against the genome and assigned to genes according to the annotation. Inconsistencies in annotations between the reference and the experimental system can lead to incorrect interpretation of the effect on RNA expression of an experimental treatment or mutation in the system under study. Until recently, the genome-wide annotation of 3-prime untranslated regions received less attention than coding regions and the delineation of intron/exon boundaries. In this paper, data produced for samples in Human, Chicken and A. thaliana by the novel single-molecule, strand-specific, Direct RNA Sequencing technology from Helicos Biosciences which locates 3-prime polyadenylation sites to within +/- 2 nt, were combined with archival EST and RNA-Seq data. Nine examples are illustrated where this combination of data allowed: (1) gene and 3-prime UTR re-annotation (including extension of one 3-prime UTR by 5.9 kb); (2) disentangling of gene expression in complex regions; (3) clearer interpretation of small RNA expression and (4) identification of novel genes. While the specific examples displayed here may become obsolete as genome sequences and their annotations are refined, the principles laid out in this paper will be of general use both to those annotating genomes and those seeking to interpret existing publically available annotations in the context of their own experimental dataComment: 44 pages, 9 figure

Status of Muon Collider Research and Development and Future Plans

The status of the research on muon colliders is discussed and plans are outlined for future theoretical and experimental studies. Besides continued work on the parameters of a 3-4 and 0.5 TeV center-of-mass (CoM) energy collider, many studies are now concentrating on a machine near 0.1 TeV (CoM) that could be a factory for the s-channel production of Higgs particles. We discuss the research on the various components in such muon colliders, starting from the proton accelerator needed to generate pions from a heavy-Z target and proceeding through the phase rotation and decay ($\pi \to \mu \nu_{\mu}$) channel, muon cooling, acceleration, storage in a collider ring and the collider detector. We also present theoretical and experimental R & D plans for the next several years that should lead to a better understanding of the design and feasibility issues for all of the components. This report is an update of the progress on the R & D since the Feasibility Study of Muon Colliders presented at the Snowmass'96 Workshop [R. B. Palmer, A. Sessler and A. Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics (Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].Comment: 95 pages, 75 figures. Submitted to Physical Review Special Topics, Accelerators and Beam

Genome and Transcriptome of Clostridium phytofermentans, Catalyst for the Direct Conversion of Plant Feedstocks to Fuels

International audienceClostridium phytofermentans was isolated from forest soil and is distinguished by its capacity to directly ferment plant cell wall polysaccharides into ethanol as the primary product, suggesting that it possesses unusual catabolic pathways. The objective of the present study was to understand the molecular mechanisms of biomass conversion to ethanol in a single organism, Clostridium phytofermentans, by analyzing its complete genome and transcriptome during growth on plant carbohydrates. The saccharolytic versatility of C. phytofermentans is reflected in a diversity of genes encoding ATP-binding cassette sugar transporters and glycoside hydrolases, many of which may have been acquired through horizontal gene transfer. These genes are frequently organized as operons that may be controlled individually by the many transcriptional regulators identified in the genome. Preferential ethanol production may be due to high levels of expression of multiple ethanol dehydrogenases and additional pathways maximizing ethanol yield. The genome also encodes three different proteinaceous bacterial microcompartments with the capacity to compartmentalize pathways that divert fermentation intermediates to various products. These characteristics make C. phytofermentans an attractive resource for improving the efficiency and speed of biomass conversion to biofuels

Krill Excretion Boosts Microbial Activity in the Southern Ocean

Antarctic krill are known to release large amounts of inorganic and organic nutrients to the water column. Here we test the role of krill excretion of dissolved products in stimulating heterotrophic bacteria on the basis of three experiments where ammonium and organic excretory products released by krill were added to bacterial assemblages, free of grazers. Our results demonstrate that the addition of krill excretion products (but not of ammonium alone), at levels expected in krill swarms, greatly stimulates bacteria resulting in an order-of-magnitude increase in growth and production. Furthermore, they suggest that bacterial growth rate in the Southern Ocean is suppressed well below their potential by resource limitation. Enhanced bacterial activity in the presence of krill, which are major sources of DOC in the Southern Ocean, would further increase recycling processes associated with krill activity, resulting in highly efficient krill-bacterial recycling that should be conducive to stimulating periods of high primary productivity in the Southern Ocean.This research is a contribution to projects ICEPOS (REN2002-04165-CO3-O2) and ATOS (POL2006-00550/CTM), funded by the Spanish Ministry of Science and Innovation