The bandmerged Planck Early Release Compact Source Catalogue: Probing sub-structure in the molecular gas at high Galactic latitude

The Planck Early Release Compact Source Catalogue (ERCSC) includes nine lists of highly reliable sources, individually extracted at each of the nine Planck frequency channels. To facilitate the study of the Planck sources, especially their spectral behaviour across the radio/infrared frequencies, we provide a "bandmerged" catalogue of the ERCSC sources. This catalogue consists of 15191 entries, with 79 sources detected in all nine frequency channels of Planck and 6818 sources detected in only one channel. We describe the bandmerging algorithm, including the various steps used to disentangle sources in confused regions. The multi-frequency matching allows us to develop spectral energy distributions of sources between 30 and 857 GHz, in particular across the 100 GHz band, where the energetically important CO J=1->0 line enters the Planck bandpass. We find ~3-5sigma evidence for contribution to the 100 GHz intensity from foreground CO along the line of sight to 147 sources with |b|>30 deg. The median excess contribution is 4.5+/-0.9 percent of their measured 100 GHz flux density which cannot be explained by calibration or beam uncertainties. This translates to 0.5+/-0.1 K km s^{-1} of CO which must be clumped on the scale of the Planck 100 GHz beam, i.e., ~10 arcmin. If this is due to a population of low mass (~15 Msun) molecular gas clumps, the total mass in these clumps may be more than 2000 Msun. Further, high-spatial-resolution, ground-based observations of the high-latitude sky will help shed light on the origin of this diffuse, clumpy CO emission.Comment: 15 pages, 15 figures, MNRAS in pres

Socio-technical transitions in UK electricity: part 1 – history, actors and pathways

A large interdisciplinary consortium of engineers, social scientists and policy analysts has developed three low-emissions, more-electric transition pathways for the UK. The approach is based on earlier work on understanding transitions, applying a multi-level perspective with landscape, regime and niche levels to the development of sociotechnical scenarios. The pathways to 2050 focus on the power sector, including the potential for increasing the use of low-emissions electricity for heating and transport. Part 1 describes studies of historical energy and infrastructure transitions that help to understand the dynamics and timing of past transitions. The role of large-scale and small-scale actors in the electricity sector and methods used to develop the pathways are then described. In part 2, associated technologies are evaluated to determine the choices that need to be made by UK energy policymakers and stakeholders. All three pathways are appraised in terms of their environmental performance using complementary life-cycle assessment and footprinting methods. Lessons can clearly be drawn for other industrialised nations attempting to reduce the emissions from their electricity generation systems, although local circumstances will determine country- and region-specific options

Socio-technical transitions in UK electricity: part 2 - technologies and sustainability

A large interdisciplinary consortium of engineers, social scientists and policy analysts has developed three low-emissions, more-electric transition pathways for the UK. The approach is based on earlier work on understanding transitions, applying a multi-level perspective with landscape, regime and niche levels to the development of sociotechnical scenarios. The pathways to 2050 focus on the power sector, including the potential for increasing the use of low-emissions electricity for heating and transport. Part 1 described studies of historical energy and infrastructure transitions that help to understand the dynamics and timing of past transitions. The role of large-scale and small-scale actors in the electricity sector and methods used to develop the pathways were also described. In part 2, associated technologies are evaluated to determine the choices that need to be made by UK energy policymakers and stakeholders. All three pathways are appraised in terms of their environmental performance using complementary life-cycle assessment and footprinting methods. Lessons can clearly be drawn for other industrialised nations attempting to reduce the emissions of their electricity generation systems, although local circumstances will determine country- and region-specific options

Polarization Observations with the Cosmic Background Imager

We describe polarization observations of the CMBR with the Cosmic Background Imager, a 13 element interferometer which operates in the 26-36 GHz band from Llano de Chajnantour in northern Chile. The array consists of 90-cm Cassegrain antennas mounted on a steerable platform which can be rotated about the optical axis to facilitate polarization observations. The CBI employs single mode circularly polarized receivers which sample multipoles from ℓ~400 to ℓ~4250. The instrumental polarization of the CBI was calibrated with 3C279, a bright polarized point source which was monitored with the VLA

In vitro susceptibility of thioredoxins and glutathione to redox modification and aging-related changes in skeletal muscle

AbstractThioredoxins (Trx's) regulate redox signaling and are localized to various cellular compartments. Specific redox-regulated pathways for adaptation of skeletal muscle to contractions are attenuated during aging, but little is known about the roles of Trx's in regulating these pathways. This study investigated the susceptibility of Trx1 and Trx2 in skeletal muscle to oxidation and reduction in vitro and the effects of aging and contractions on Trx1, Trx2, and thioredoxin reductase (TrxR) 1 and 2 contents and nuclear and cytosolic Trx1 and mitochondrial Trx2 redox potentials in vivo. The proportions of cytosolic and nuclear Trx1 and mitochondrial Trx2 in the oxidized or reduced forms were analyzed using redox Western blotting. In myotubes, the mean redox potentials were nuclear Trx1, −251mV; cytosolic Trx1, −242mV; mitochondrial Trx2, −346mV, data supporting the occurrence of differing redox potentials between cell compartments. Exogenous treatment of myoblasts and myotubes with hydrogen peroxide or dithiothreitol modified glutathione redox status and nuclear and cytosolic Trx1, but mitochondrial Trx2 was unchanged. Tibialis anterior muscles from young and old mice were exposed to isometric muscle contractions in vivo. Aging increased muscle contents of Trx1, Trx2, and TrxR2, but neither aging nor endogenous ROS generated during contractions modified Trx redox potentials, although oxidation of glutathione and other thiols occurred. We conclude that glutathione redox couples in skeletal muscle are more susceptible to oxidation than Trx and that Trx proteins are upregulated during aging, but do not appear to modulate redox-regulated adaptations to contractions that fail during aging

A low carbon industrial revolution? Insights and challenges from past technological and economic transformations

Recent efforts to promote a transition to a low carbon economy have been influenced by suggestions that a low carbon transition offers challenges and might yield economic benefits comparable to those of the previous industrial revolutions. This paper examines these arguments and the challenges facing a low carbon transition, by drawing on recent thinking on the technological, economic and institutional factors that enabled and sustained the first (British) industrial revolution, and the role of ‘general purpose technologies’ in stimulating and sustaining this and subsequent industrial transformation processes that have contributed to significant macroeconomic gains. These revolutions involved profound, long drawn-out changes in economy, technology and society; and although their energy transitions led to long-run economic benefits, they took many decades to develop. To reap significant long-run economic benefits from a low carbon transition sooner rather than later would require systemic efforts and incentives for low carbon innovation and substitution of high-carbon technologies. We conclude that while achieving a low carbon transition may require societal changes on a scale comparable with those of previous industrial revolutions, this transition does not yet resemble previous industrial revolutions. A successful low carbon transition would, however, amount to a different kind of industrial revolution

SplicerAV: a tool for mining microarray expression data for changes in RNA processing

<p>Abstract</p> <p>Background</p> <p>Over the past two decades more than fifty thousand unique clinical and biological samples have been assayed using the Affymetrix HG-U133 and HG-U95 GeneChip microarray platforms. This substantial repository has been used extensively to characterize changes in gene expression between biological samples, but has not been previously mined <it>en masse </it>for changes in mRNA processing. We explored the possibility of using HG-U133 microarray data to identify changes in alternative mRNA processing in several available archival datasets.</p> <p>Results</p> <p>Data from these and other gene expression microarrays can now be mined for changes in transcript isoform abundance using a program described here, SplicerAV. Using <it>in vivo </it>and <it>in vitro </it>breast cancer microarray datasets, SplicerAV was able to perform both gene and isoform specific expression profiling within the same microarray dataset. Our reanalysis of Affymetrix U133 plus 2.0 data generated by <it>in vitro </it>over-expression of HRAS, E2F3, beta-catenin (CTNNB1), SRC, and MYC identified several hundred oncogene-induced mRNA isoform changes, one of which recognized a previously unknown mechanism of <it>EGFR </it>family activation. Using clinical data, SplicerAV predicted 241 isoform changes between low and high grade breast tumors; with changes enriched among genes coding for guanyl-nucleotide exchange factors, metalloprotease inhibitors, and mRNA processing factors. Isoform changes in 15 genes were associated with aggressive cancer across the three breast cancer datasets.</p> <p>Conclusions</p> <p>Using SplicerAV, we identified several hundred previously uncharacterized isoform changes induced by <it>in vitro </it>oncogene over-expression and revealed a previously unknown mechanism of EGFR activation in human mammary epithelial cells. We analyzed Affymetrix GeneChip data from over 400 human breast tumors in three independent studies, making this the largest clinical dataset analyzed for <it>en masse </it>changes in alternative mRNA processing. The capacity to detect RNA isoform changes in archival microarray data using SplicerAV allowed us to carry out the first analysis of isoform specific mRNA changes directly associated with cancer survival.</p

Developing transition pathways for a low carbon electricity system in the UK

This paper describes outline transition pathways for a low carbon energy system in the UK, which are currently being developed in a collaborative research project, involving leading UK engineers, social scientists and policy analysts. The pathways are exploring different governance patterns, relating to the roles of central government, market actors and structures, and civil society, in relation to both centralised and decentralised systems for meeting energy service demands. This work is using a conceptual and analytical framework for specifying transition pathways that relates the multi-level perspective of landscape, regime and niche levels to recent work on technological innovation systems. The specification of the pathways draws on earlier work on UK energy and international energy scenarios, initial interviews with ‘gatekeepers’ from the UK energy policy and industry communities, and useful insights from a workshop with invited stakeholders from the policy-making, industry and academic communities, held in November 2008. The pathways explore how social and political issues, such as public acceptability of different technologies and institutional changes, the mixture of short-term and long-term drivers and influences affecting policy-making, and the strategies of large and small firms, interact or ‘co-evolve’ with present and expected future changes in technologies

Origins of the sarsen megaliths at Stonehenge

The sources of the stone used to construct Stonehenge around 2500 BCE have been debated for over four centuries. The smaller “bluestones” near the center of the monument have been traced to Wales, but the origins of the sarsen (silcrete) megaliths that form the primary architecture of Stonehenge remain unknown. Here, we use geochemical data to show that 50 of the 52 sarsens at the monument share a consistent chemistry and, by inference, originated from a common source area. We then compare the geochemical signature of a core extracted from Stone 58 at Stonehenge with equivalent data for sarsens from across southern Britain. From this, we identify West Woods, Wiltshire, 25 km north of Stonehenge, as the most probable source area for the majority of sarsens at the monument